Due to the lack of an etiologic treatment for SARS-CoV-2 and the difficulties involved in developing new drugs, some drugs already approved for other diseases or with efficacy against SARS and MERS, have been used in patients with COVID-19. This systematic review aims to summarize evidence on the efficacy and safety of five antivirals applied to patients with COVID-19, that have proven to be effective either in vitro studies or in studies on SARS-CoV and MERS.; An intensive search of different databases  has been carried out until the end of April 2021. This systematic review has been conducted according to the PRISMA statement. From each of the included studies, the characteristics of the intervention and comparison groups, demographic data and results were extracted independently; Remdesivir is well tolerated and helps to accelerate clinical improvement but is ineffective in reducing mortality. Favipiravir is safe and shows promising results regarding symptom resolution but does not improve viral clearance. The use of lopinavir/ritonavir has been associated with an increased risk of gastrointestinal adverse events and it has not proven to be effective. No significant differences were observed between patients treated with ribavirin or umifenovir and their respective control groups; Remdesivir and favipiravir are well tolerated and effective in accelerating clinical improvement. This systematic review does not support the use of lopinavir/ritonavir, ribavirin and umifenovir in hospitalized patients with COVID-19. Members of the family Coronaviridae are widely spread among mammals, usually triggering respiratory infections . Until 2However, this perception changed in 2002 as a result of an outbreak of cases in China with severe respiratory symptoms, currently known as Severe Acute Respiratory Syndrome (SARS) . A similThe latest coronavirus with pathogenicity for humans that has been identified to date is SARS-CoV-2 . At the SARS-CoV-2 is responsible for the disease known as COVID-19, whose dominant route of transmission is respiratory  and patiSARS-CoV-2 is a positive-sense single-stranded RNA virus (+ssRNA)  and encoThe entry of SARS-CoV-2 into the host cell occurs thanks to the binding of the viral spike (S) proteins to its host target cell receptor, which is the angiotensin-2 converting enzyme (ACE-2) . This peAs the virus replicates inside the host cell, the production of type I interferon (IFN) begins. It will interact with other cells of the immune system such as macrophages and neutrophils, considered major sources of pro-inflammatory cytokines and chemokines such as IL-1β, IFNγ, tumor necrosis factor alpha (TNFα), inducible protein-10 (IP-10) and monocyte chemoattractant protein- 1 (MCP-1), which can lead to the activation of T-helper-1 cells (Th1) . In addiThe most frequent symptoms are fever, cough, asthenia, dyspnoea, myalgia or arthralgia, ageusia and anosmia ,24. OtheIf the immune response is effective, approximately 80% of infected patients have a mild or even an asymptomatic clinical course . HoweverUp to the present day we lack an etiological treatment against COVID-19, which is why the therapeutic strategies used are being oriented in three main directions .One way is trying to reduce or eliminate the SARS-CoV-2 viral load using molecules capable of interfering with viral replication. Another way is using immune therapies that allow regulating the inflammatory response and finally, the other therapeutic strategy used is symptomatic treatment, for example, providing oxygen . AntivirSome of the antivirals used against SARS-CoV-2, among other non-antiviral molecules are shown in Since the beginning of the pandemic, a major scientific effort has been made to develop a vaccine that will make it possible to immunize the population and thus reduce the incidence of this virus. As of 14 July 2021, a total of 3,400,884,367 vaccine doses have been administered around the world [Currently there are three main types of vaccines against SARS-CoV-2 virus. On the one hand, the messenger-RNA (mRNA) vaccines use manufactured nucleoside-modified, single stranded mRNA, that contain the genetic code for the synthesis of the SARS-CoV-2 S protein antigen ,38. GiveIt should be noted that this type of vaccine is very vulnerable at room temperature, which is why it must be stored at −70 °C or −20 °C. This can be a problem in developing countries, where the continued supply of electricity to large industrial freezers is unreliable .Nowadays there are two COVID-19 mRNA vaccines approved for market: mRNA-1273 developed by Moderna and BNT162b2 developed by Pfizer-BioNTech . On the We can also find inactivated coronavirus vaccines, created by using radiation, heat or chemical stress . This tyGiven the urgent need to reduce the cost, time and risks derived from the development of new medicines, drugs already approved for other indications have been ‘’repurposed’’ and used to treat COVID-19 patients.Nowadays, not too many studies regarding the use of antiviral drugs on patients with SARS-CoV-2 infection have been carried out. The present study aims to summarize evidence on the efficacy and safety of five antivirals applied to patients with COVID-19, that have proven to be effective either in in vitro studies or in studies on SARS-CoV and MERS ,43.The search was made using PubMed, Scopus, Web of Science, MEDLINE, and Cochrane COVID-19 Study Register, which also includes trials published in ClinicalTrials.gov-COVID-19 subset and WHO International Clinical Trials Registry Platform (ICTRP).The studies have been identified by combining the name “coronavirus”, “COVID-19” and “SARS-CoV-2” with the following keywords: lopinavir/ritonavir, remdesivir, favipiravir, umifenovir, ribavirin or their respective trade names. MeSH terms  and the Boolean operators “AND’’ and ‘’OR’’ have also been used in the search.The study was conducted according to the PRISMA statement . ArticleRegarding type of studies, both randomized controlled clinical trials (RCTs) and observational studies were included. The rest of the inclusion criteria have been proposed according to the PICO algorithm .The proposed exclusion criteria for this systematic review have been: (a) studies with insufficient data, (b) in vitro, in silico, in vivo animal studies, (c) comments, expert opinions, case reports, letters to the editor, reviews, protocols and trial registry records, (d) studies including patients with other coronaviruses, SARS, or MERS, (e) studies that do not include as an intervention at least one of the five antivirals evaluated in this systematic review, (f) studies using medicinal plants.The following information has been extracted from each of the included studies: (a) clinical trial registration number, (b) author, (c) publication date, (d) trial design, (f) participant characteristics (severity of the disease), (g) country, (h) interventions carried out with their respective dosage regimen, (i) comparison group dosage regimen (i) number of participants recruited/allocated/evaluated, (j) age and gender of participants, (k) outcomes.We included nine studies about remdesivir, which is the first FDA-approved drug for COVID-19 . Six of p = 0.02) [p = 0.18) [p > 0.05) [One of the RCTs carried out in multiple centres in the USA, Europe and Asia simultaneously, compared a 10-day course of remdesivir and a 5-day course with standard of care . Patient = 0.02) . In cont = 0.18) . Other o > 0.05) .p = 0.14), length of hospital stay, discharge rate, time to recovery, and mortality [Goldman et al. compared a 5-day course of remdesivir with a 10-day course in patients with severe COVID-19. Despite an apparent trend towards better outcomes in patients treated with remdesivir for 5 days than those receiving it for 10 days, the differences were not statistically significant. After adjusting for baseline imbalances in severity disease, similar results were obtained between both groups in terms of clinical status at day 14  as well as higher odds of improvement in the eight-category ordinal scale on day 15, where “1” corresponds to not having any limitations and “8” means death  [The first phase of the “Adaptive COVID-19 treatment trial or ATT-1” constitutes a RCT where 541 patients allocated to remdesivir therapy were compared with 521 patients randomized to placebo . The dat1.2–1.9) . Additional secondary end points that support the use of remdesivir are: a shorter time to improvement of one and of two categories on the 8-category ordinal scale, a shorter time to discharge, and a shorter length of hospital stay (12 days versus 17 days in the remdesivir and placebo groups respectively). Moreover, mortality by day 29 was 11.4% in the remdesivir group versus 15.2% in the placebo group  .p = 0.0672) did not show a significant improvement in the intervention group either [Wang et al. recruited a total of 237 severe COVID-19 patients (158 randomized to remdesivir therapy and 78 to placebo) in China at the start of the pandemic . Althougp either . It is ip either .p = 0.50) nor the percentage of patients requiring mechanical ventilation after randomization [These results are in line with those of the ‘’WHO Solidarity Trial Consortium”, in which several intervention arms were compared with standard of care. The use of remdesivir as monotherapy did not significantly reduce 28-day mortality  [One of the observational studies included in this systematic review retrospectively compared 25 critically ill patients undergoing mechanical ventilation, who had received remdesivir with 26 patients treated with standard of care . In this <0.001) . It shou <0.001) .p < 0.001). In addition, remdesivir was associated with greater clinical improvement, assessed using a 7-category ordinal scale, as well as, with 62% lower odds of all-cause death compared with the standard of care cohort  [Olender et al. used data from a phase 3 remdesivir RCT and compared it with a longitudinal retrospective cohort of patients treated with standard of care . By day = 0.001) . p > 0.05). No significant differences could be found in terms of time to clinical recovery and time to discharge  [In line with the results seen so far, there are also those observed in another retrospective study where a group of 99 patients treated with remdesivir was compared with 125 patients who had received supportive care . Despitectively) .p = 0.03) and in increasing improvement in clinical status by day 15  [Finally, there is a double-blind RCT that has analysed the potential efficacy of remdesivir in combination with another drug. More specifically, it compares the use of remdesivir associated with barticinib versus remdesivir + placebo . This st1.0–1.6) .p = 0.02). Adverse events that were more common in the remdesivir group than in the standard of care group were: nausea, hypokalaemia, and headache. With regard to severe adverse events, they were numerically lower in both remdesivir intervention arms than in the control group, albeit not statistically significant [The RCT by Spinner et al. showed that those randomized to a 10-day course of remdesivir had significantly higher rates of adverse events compared to those receiving standard of care  and those allocated to a long course of remdesivir (10 days) .Data from the ACTT-1 trial suggest that remdesivir treatment may have prevented the progression to more severe respiratory disease. This can be evidenced by the lower proportion of serious adverse events due to respiratory failure among patients in the remdesivir group as well as a lower incidence of new use of oxygen among patients who were not receiving oxygen at the time of recruitment  .In the RCT proposed by Wang et al. remdesivir was well tolerated and no new safety concerns were identified. The overall proportion of patients with serious adverse events tended to be lower in remdesivir-treated patients (18%) than in placebo-treated patients (26%) .Nevertheless, there was a higher rate of premature discontinuation of treatment in the intervention group (12%) compared to the placebo group (5%) because of adverse events such as gastrointestinal symptoms , increases in aminotransferase or bilirubin levels and worsening of cardiopulmonary status .p > 0.05) [Another observational study found that the therapy with remdesivir did not increase liver test abnormalities and was not associated with a higher risk of acute kidney injury  .p = 0.03) [In the case of the study that has compared the combination of remdesivir with barticinib versus remdesivir alone, those receiving dual therapy have presented significantly fewer serious adverse reactions  .Five RCTs and ten observational studies regarding lopinavir/ritonavir have been included .In an RCT carried out in China, 99 patients with severe COVID-19 randomized to lopinavir/ritonavir were compared with those allocated to standard of care. This study found that treatment with lopinavir/ritonavir was not associated with significant clinical improvement, mortality reduction or reduction in viral RNA detectability, since SARS-CoV-2 RNA was still detectable in 40.7% of the patients treated with lopinavir/ritonavir at the end of the study (day 28) . It shoup = 0.60), in length of hospital stay, as well as in risk of progressing and needing invasive mechanical ventilation , which is why they conclude that lopinavir/ritonavir monotherapy is not an effective treatment for hospitalized COVID-19 patients [The results of the RECOVERY trial carried out in the United Kingdom, which enrolled 5040 patients, indicate that compared to standard of care, lopinavir/ritonavir is not associated with significant reduction in mortality , as well as in a faster resolution of symptoms assessed by the SOFA score  [In the RCT by Hung et al., the patients allocated to the triple therapy of lopinavir/ritonavir + ribavirin + IFN-ß1b were compared with those in the control group receiving lopinavir/ritonavir monotherapy. The results show that this triple therapy applied within 7 days of symptom onset is effective in suppressing SARS-CoV-2 shedding . This po= 0.041) . The DisCoVery trial is an RCT carried out in multiple French healthcare centres simultaneously, in which several lines of treatment have been investigated . While iNone of these investigational treatments resulted in significant clinical improvement at day 15 and at day 29, as measured on the WHO-7-point ordinal scale, where “1” implies the absence of activity limitations or need for hospitalization and “7” equals death .p = 0.39), while at day 29 it was OR = 0.93  [p = 0.08) and at day 29 it was OR = 0.76  [In more detail, the odds for clinical status improvement at day 15 in the lopinavir/ritonavir monotherapy group versus the standard of care group was OR = 0.83  . In the  = 0.19) . Likewis = 0.19) .p = 0.97) and the percentage of patients requiring mechanical ventilation after randomization [These results are in line with those of the WHO Solidarity Trial Consortium, in which several lines of treatment were compared with standard of care internationally. One of them was lopinavir/ritonavir in monotherapy, but it failed to reduce mortality , the time to viral clearance , nor prevents the progression to severe cases  [Regarding the observational studies included, Gao et al. have found no evidence that lopinavir/ritonavir monotherapy accelerates the remission of symptoms like fever  .Following this line of results, Grimaldi et al. compared a total of 57 patients receiving lopinavir/ritonavir with a cohort of 85 patients treated with standard of care . Here, tp < 0.0001) [The same occurs in the retrospective cohort study by Choi et al., where the median viral shedding duration was longer in patients treated with lopinavir/ritonavir (23 days) compared to those who only received standard of care (18 days) ( 0.0001) .p = 0.0219), as well as time to defervescence (p = 0.0364) when compared to standard of care [On the contrary, Ye et al., observed that patients treated with lopinavir/ritonavir monotherapy accelerated time to viral clearance , ventilator free days, 14-day mortality and 28-day mortality and change in viral load between admission and day 7, was the retrospective study by Lecronier et al., where 20 patients treated with lopinavir/ritonavir were compared with 22 receiving standard of care .p = 0.001) and median duration of hospital stay  [Lu et al. studied the use of lopinavir/ritonavir monotherapy in paediatric patients with mild COVID-19. They could observe that the intervention group had a disadvantage compared with those receiving standard of care, in terms of time to viral clearance  .p = 0.213) and 30-day mortality (p = 0.271) [Other authors have tried to evaluate the differences in clinical efficacy between an early treatment (begin within 5 days of symptom onset) of lopinavir/ritonavir + hydroxychloroquine and a delayed treatment . The res= 0.271) .p < 0.01). Additionally, the duration of positive RNA test was shorter in the arbidol group (p < 0.01) [Lopinavir/ritonavir has also been compared with other antivirals. In a retrospective study carried out in China 36 patients who received lopinavir/ritonavir were compared with 16 patients treated with arbidol (trade name of umifenovir) . Arbidol < 0.01) .p = 0.319) or in-hospital mortality (p = 0.639) [Vernaz et al. propose in their retrospective single-centre study several intervention arms containing lopinavir/ritonavir. In one of them lopinavir/ritonavir monotherapy is compared with standard of care and no statistically significant differences can be found between both groups in terms of length of hospital stay (= 0.639) .p = 0.697) and it was significantly associated with an increase in length of stay (p < 0.001) [In another of the intervention arms, a group of patients treated with hydroxychloroquine + lopinavir/ritonavir was compared with a cohort that had received standard of care. This combination therapy failed to reduce mortality (< 0.001) .p = 0.02). However, subgroup analysis revealed that this shorter duration was only statistically significant in those patients treated within 10 days from symptom onset (log-rank p < 0.0001), unlike those who received it eleven or more days later (log-rank p = 0.51) [Finally, the last observational study included in this systematic review coincides with the results proposed by Yan et al., since the group of patients treated with lopinavir/ritonavir had a significant shorter duration of viral shedding compared to the control group ( = 0.51) . It is t = 0.51) .Cao et al. conclude that gastrointestinal adverse events were more common in lopinavir/ritonavir group than in those who received standard of care. However, the number of patients with severe complications  was higher in the control group. In total, 13 patients had to stop prematurely the use of lopinavir/ritonavir because of adverse events .On the contrary, the DisCoVery trial recorded a significantly higher number of serious adverse events in those treated with lopinavir/ritonavir, either in monotherapy or associated with IFN-β1a. The most frequently reported ones were: acute respiratory failure (11%), acute kidney injury (8.2%), acute respiratory distress syndrome (8%), arrhythmia (7%), pulmonary embolism (5%) and sepsis (4%) .p > 0.05), being those side effects generally mild and self-limiting [Hung et al. reported no statistically significant differences between intervention and control group regarding adverse events , which is why this study raises concerns about the safety profile of this antiviral [Grimaldi et al. registered a statistically significant higher incidence of cases of acute kidney injury (AKI) and need for renal replacement therapy (RRT) at day 28 in the lopinavir/ritonavir group compared to the control group  [In the study by Lu et al. the use of lopinavir/ritonavir in paediatric patients was associated with significantly higher adverse reactions compared to those who received conventional treatment, mainly because of a longer nasopharyngeal swab negativitation time  .Finally, coinciding with Cao et al., a retrospective study also observed that the most frequent adverse events in patients treated with lopinavir/ritonavir were gastrointestinal symptoms including nausea, diarrhoea and elevated liver enzymes, in fact 8.1 % of the patients developed grade 2–3 gastrointestinal disorders and had to discontinue the treatment prematurely .After literature search and careful review of full-text articles, a total of six RCTs and two observational studies on favipiravir have been included .p > 0.05) [p = 0.048) [One of the RCTs carried out in Japan, compared the early administration of favipiravir in patients with asymptomatic or mild COVID-19 with its late administration (starting on day 6 of study) . Early f > 0.05) . What wa= 0.048) .Another RCT was carried out in India and it compared the use of favipiravir in adults with mild to moderate COVID-19 with supportive care .p = 0.098) and of time to hospital discharge  could not be reached, significant results were found regarding a reduction in time to clinical cure in those treated with favipiravir  [While a statistically significant difference in terms of time to cessation of viral shedding  . This le= 0.019) .The results obtained in another RCT carried out in Russia, in which 17 patients receiving favipiravir monotherapy were compared with 22 patients receiving standard of care, have been encouraging . It shoup < 0.05 respectively) [Favipiravir turned out to be more effective than the standard etiotropic therapy used as control group in various aspects such as: in reducing the time to defervescence, in having lower lactate levels in blood at the end of the treatment and in reducing the area of pulmonary parenchyma lesion according to the CT data (ctively) .p = 0.06), lower mortality rates (p = 1.00) and none of them required mechanical ventilation (p = 0.118) [In Egypt, the authors Dabbous et al. found in their RCT promising results regarding the use of favipiravir when compared to chloroquine. Although the differences were not statistically significant, those receiving favipiravir had a shorter duration of hospital stay (= 0.118) .p = 0.018) [p = 0.007) [In a phase II/III RCT, Ivashchenko et al. studied two possible favipiravir dosing regimens and compared each of them with a standard of care. In this study the patients were randomized 1:1:1 to receive either 1600 mg favipiravir, twice the first day, followed by 600 mg twice a day for 14 days, or 1800 mg favipiravir, twice the first day followed by 800 mg twice a day for 14 days or standard of care . On both= 0.018) . Likewis= 0.007) .p = 0.019) and in reducing mortality [In the last included RCT, three possible intervention arms were compared: favipiravir + tocilizumab; favipiravir monotherapy and tocilizumab monotherapy . The simortality . The comortality .p < 0.001), as well as to improve chest CT inflammatory changes on day 14 after treatment (p = 0.004) [Combinations of favipiravir with other drugs were studied in the following observational studies. Cai et al. proposed a comparative study in which the intervention group received favipiravir and IFN-α1b, while the control group received lopinavir/ritonavir associated with IFN-α1b. Those treated with favipiravir appeared to accelerate viral clearance (= 0.004) .p = 0.237), which could be due to the small sample size of the study. On the other hand, favipiravir was superior to lopinavir/ritonavir in shortening the length of ICU stay (p = 0.01) [In a retrospective study carried out in Turkey favipiravir was also compared with lopinavir/ritonavir, however, in this case both were simultaneously given with hydroxychloroquine . On the  = 0.01) .The most frequent adverse event recorded in 84.1% of the patients after favipiravir administration was hyperuricemia. Other reported adverse events were: elevation of serum triglycerides (11%) and serum alanine aminotransferase elevation (8.5%) .These observed adverse events coincide with those of Udwadia et al., where most of them were mild and transient. Hyperuricemia and elevated liver enzymes were the most common ones detected in the favipiravir group. The reported gastrointestinal disorders were minimal and similar between intervention and supportive care groups .In another RCT, it was found that, in terms of QTc prolongation, the use of favipiravir was safer than standard therapy, represented mostly by hydroxychloroquine and azithromycin. The rest of the recorded side effects were mild in form and associated with hepatotoxicity .Following this line of results, the undesirable events reported by a study with two dosing regimens for favipiravir were mild to moderate in severity and consistent with those reported so far for this antiviral. In addition, those who received higher doses of favipiravir did not experience any increasing toxicity .p < 0.001), being the most frequent one gastrointestinal disorders including diarrhoea, liver injury, nausea and vomiting [In one of the studies comparing the efficacy of favipiravir versus lopinavir/ritonavir, higher rates of adverse events in lopinavir/ritonavir group (55.56%) were noticed compared to favipiravir group (11.43%) , time to fever resolution (p=0.55), proportion of patients with SARS-CoV-2 nucleic acid negativity at day 14 and day 28, CT-changes improvement (p = 0.76), length of hospital stay (p = 0.56) or mortality [The other RCT included in this systematic review compared the efficacy of ribavirin in combination with other drugs, specifically, 33 patients were randomized to treatment with ribavirin and IFN-α, 36 received lopinavir/ritonavir + IFN-α and 32 patients were assigned to a triple therapy of ribavirin, IFN-α and lopinavir/ritonavir . The resortality .p < 0.001) [Among the studies where ribavirin was given concomitantly with other drugs, in the one by Elalfy et al. the combination treatment of ribavirin + nitazoxanide + ivermectin + zinc supplement proved to be effective in clearing SARS-CoV-2 in a shorter time than those treated with standard of care (< 0.001) .p = 0.475) or accelerate time to viral clearance (p = 0.314) [Finally, one of the observational studies compared the use of ribavirin in patients with severe COVID-19 with a cohort of patients who had received supportive care and found that ribavirin failed to significantly reduce mortality (= 0.314) .Huang et al. found that the combination of ribavirin with lopinavir/ritonavir was associated with a significant increase in gastrointestinal disorders, thus suggesting that both antivirals should not be administered simultaneously in patients with COVID-19 .Eslami et al., also observed that the most frequent adverse events in the ribavirin group were gastrointestinal in nature such as nausea, vomiting, diarrhoea, abdominal pain and bleeding .In the study by Tong et al., ribavirin was well tolerated, with anaemia being the most frequent side effect. To this must be added, that there was no premature discontinuation of treatment as a consequence . In the This systematic review has included one RCT and five observational studies regarding umifenovir or better known as its trade name, arbidol .p = 0.02) and by presenting a higher peripheral oxygen saturation on the seventh day of treatment (p = 0.02) and milder involvement of the chest-CT scan after 30 days (p = 0.004) [Starting with the Iranian RCT that enrolled 100 patients, 50 of them were assigned to a double therapy of arbidol + hydroxychloroquine, while the other half received hydroxychloroquine and lopinavir/ritonavir . In this= 0.004) . p = 0.2). Other parameters like need of intubation (p = 0.6), need of mechanical ventilation (p = 0.6) or mortality (p = 0.5) did not show significant differences either [Regarding time to defervescence, despite being numerically lower in the arbidol group, the difference was not statistically significant . However, in terms of length of hospital stay, the differences between arbidol and standard therapy were not statistically significant [Another retrospective study found that arbidol compared to standard therapy could shorten time to viral clearance, as well as accelerate clinical cure by relieving fever and dry cough faster (nificant .p < 0.05) [Deng et al. compared in their retrospective study a cohort of patients who had received arbidol and lopinavir/ritonavir versus a control group only treated with lopinavir/ritonavir. They observed that the combination group presented higher viral negative conversion rates ( < 0.05) .p = 0.057) or reducing length of hospital stay (p = 0.056). However, it did significantly accelerate pneumonia absorption observed through CT (p = 0.037) [In another retrospective cohort where arbidol associated with IFN-α2b was compared with IFN-α2b monotherapy, dual therapy was not effective in terms of accelerating viral clearance (= 0.037) . The dat= 0.037) .p = 0.002) and shorter length of hospital stay [Arbidol given to a group of 90 patients revealed beneficial effects in comparison to 45 patients who received standard of care. These benefits were mainly observed in aspects such as higher viral clearance rates , and the dual therapy lopinavir/ritonavir, in terms of their efficacy and safety when applied to SARS-CoV-2 infected patients.Regarding remdesivir efficacy, none of the randomized controlled clinical trials have shown statistically significant benefits in terms of mortality ,47,49,50When it comes to the question of how long remdesivir should be given, there are discrepancies between studies. In the study by Spinner et al. remdesivir therapy for 5 days was more likely to have a better clinical status on day 11 compared to standard of care .Parallelly, Goldman et al. compared a 5-day regimen of remdesivir versus a 10-day course and despite noticing a trend toward better outcomes in patients receiving it for 5 days, the differences were not statistically significant . These rOn the one hand, this meta-analysis reveals that those who received a 5-day remdesivir therapy had greater clinical improvement compared to those in the control group . On the other hand, no statistically significant differences were observed between those with a 10-day remdesivir regimen and those receiving placebo  .Contrary to the results recorded in the RCTs, several of the included observational studies, do detect a significant reduction in mortality in remdesivir group ,52. However, it must be taken into account that the lack of randomization, the small sample size in the case of Pasquini et al.  or the uRegarding safety, no significant association has been found between an increased risk of suffering an adverse event and the use of remdesivir ,48,49,53Large randomized controlled clinical trials on the use of lopinavir/ritonavir applied to COVID-19 patients, have revealed a lack of efficacy in terms of clinical improvement, mortality reduction, viral clearance, length of hospital stay, oxygenation-free days and mechanical ventilation-free days ,55,56,58These results are consistent with those of a meta-analysis published online in April 2021 where the differences between lopinavir/ritonavir group and those receiving standard therapy were not statistically significant in terms of mortality, viral clearance  and radiological improvement  .The majority of the observational studies included in this systematic review coincide with the results proposed by the RCTs and neither did they find benefits regarding the use of lopinavir/ritonavir compared to standard of care ,63,64,67Other authors have compared the efficacy of lopinavir/ritonavir administered simultaneously with other drugs such as IFN-ß1a  or hydroRegarding safety, gastrointestinal adverse events like nausea, vomiting and diarrhoea have been more common in those who received lopinavir/ritonavir ,57,65.While it is true that most of the studies included in this review recorded mild and self-limited adverse events, in some studies like the one by Grimaldi et al. there was a higher incidence of acute renal injury and need for renal replacement therapy in those receiving lopinavir/ritonavir, thus raising doubts about its safety profile . Likewise, lopinavir/ritonavir proved to be inadequate to treat paediatric population since the number of adverse events was significantly higher in this group compared to those who received standard therapy .Treatment with favipiravir has shown efficacy in accelerating clinical cure, specifically time to defervescence ,71,73. HIt should be noted that the benefits recorded in the study by Balykova et al. regarding the use of favipiravir versus standard of care are difficult to quantify since the standard therapy consisted of various combinations of drugs, mainly hydroxychloroquine, azithromycin and lopinavir/ritonavir .In a meta-analysis published in September 2020, several of the studies included in this systematic review were analysed. The group of patients treated with favipiravir showed a significant clinical improvement by day 14  compared to the control group. In contrast, viral clearance by 14 day  and need for oxygen or non-invasive mechanical ventilation  did not show statistically significant differences between groups .The combination of favipiravir with tocilizumab seems to have promising results in terms of reducing lung parenchyma inflammation, as well as in recovering clinical symptoms compared to favipiravir monotherapy . FinallyIn terms of safety, patients treated with favipiravir experienced fewer adverse events than their respective control groups, being the most common symptom hyperuricemia. The results obtained in the just mentioned meta-analysis, revealed no significant differences between favipiravir and control group  .Ribavirin has not proven to be effective in reducing mortality, time to viral clearance, length of hospital stay, or in alleviating symptoms in any of the studies included in this review ,78,79,81Some of the studies assessed the efficacy of ribavirin combined with other drugs ,78,80, bIn terms of safety ribavirin was well tolerated, however, its concomitant use with lopinavir/ritonavir seems to potentiate gastrointestinal disorders, therefore this combination is not recommended in patients with COVID-19 .We have only been able to include one RCT on arbidol in this systematic review. Here, the association of arbidol with hydroxychloroquine significantly reduced the length of hospital stay, as well as improved radiological lung parenchyma changes compared to the group treated with lopinavir/ritonavir .Likewise, one of the included observational studies also verified the superiority of arbidol against lopinavir/ritonavir and registered significantly higher viral clearance in the group treated with arbidol . This apFinally, three studies compared the efficacy of arbidol versus standard therapy ,84,87. TNone of the studies detected serious adverse events leading to discontinuation of treatment because of the use of arbidol. A meta-analysis published in January 2021 supports some of the results just presented, such as the safety of arbidol  or the lack of efficacy of arbidol in reducing the length of hospital stay [Some of the antivirals of the current paper have either been administered concomitantly or compared with hydroxychloroquine. This drug is a 4-aminoquinoline compound that has been used as an antimalarial for years . Due to In fact, given its lack of benefit in terms of mortality, the hydroxychloroquine arms were discontinued in both SOLIDARITY  and RECOThese findings have subsequently been confirmed by several meta-analyses. In one published in September 2020, those treated with hydroxychloroquine failed to achieve a significant reduction in mortality  as well as to shorten time to defervescence compared to those treated with standard of care . The useOnce summarized evidence on the efficacy and safety of some antivirals that have proven to be effective, there is no doubt that the SARS-CoV-2 pandemic implies a major threat to human health. However, while it is essential to find a vaccine to immunize the population, this is a long-term solution. In the meantime, we must continue to invest in and support pharmacological research. Firstly, to be able to treat already infected patients. Secondly, to ensure that in regions where access to vaccines is limited, there are means to counteract this disease. Thirdly, since it is yet unclear whether the authorized vaccines are effective against the new viral strains of concern, which are the result of mutations accumulation .As a reflection, given the similarity of this new virus to the coronaviruses responsible for the SARS and MERS epidemics in 2002 and 2012 respectively, we could think that, almost a decade later, effective antivirals would be available to treat them. However, this is not the case. This leads us to believe that, by affecting only a limited geographical region, once the incidence started to decrease and the disease was controlled locally, it lost the interest of large institutions to continue researching on a suitable pharmacological treatment. Hence, it is very important to keep researching, even when effective vaccines are already available or the incidence is starting to decline. New variants of the virus may emerge in the future or a new wave of cases may arise, for which having an effective drug would be very helpful.The main limitations found in the studies included in this systematic review are the following. On the one hand, most of them had an open design, so knowing the drug being administered may have influenced the clinical outcomes. On the other hand, many of the studies did not collect detailed information about adverse events or reasons for abandoning treatment. Therefore, the conclusions obtained in terms of safety are reduced, which limits their interpretation.The absence of placebo as a comparative method in most of the included studies makes it difficult to determine whether the observed results are due to the evolution of the curative process of the disease itself, to the antiviral treatment used, or to a combination of both. Another limitation would be the small sample size used in some of the studies.In the studies where patients with COVID-19 of mild to moderate severity were recruited, it was more difficult to assess the symptoms, thus contributing to a possible underestimation of potential clinical benefits of the antivirals applied. That is why, the results of these studies cannot be extrapolated to severe or critically ill COVID-19 patients.Many of the antiviral agents were used in combination with other medications, implying that the observed results cannot be exclusively attributed to the antiviral treatment.Finally, it should be noted that even though systematic reviews constitute the “gold standard” when it comes to synthesizing the evidence to answer a scientific question, these types of articles require a great investment of time, which makes their information quickly obsolete, especially in an emergency health situation like the current one, in which new studies are constantly being published.Remdesivir may help accelerate clinical improvement in hospitalized COVID-19 patients, but it is not effective in reducing mortality. Regarding the duration of the treatment, a 5-day course seems to be sufficient. In terms of safety, this drug has proven to be as tolerable as placebo or other drugs that it has been compared to.Lopinavir/ritonavir has not proven to be an effective treatment for patients with SARS-CoV-2 infection in improving clinical status, reducing mortality, or increasing viral clearance. In fact, it has been associated with a higher risk of gastrointestinal adverse events.Treatment with favipiravir is associated with significant clinical improvement, mainly in reducing time to fever resolution, and is also safe and well-tolerated. Likewise, the combination of favipiravir with tocilizumab seems to have promising results in terms of reducing lung parenchyma inflammation and symptom resolution. However, the use of favipiravir has failed to increase viral clearance.Ribavirin has not proven to be an effective treatment for COVID-19 patients, and its concomitant use with lopinavir/ritonavir is not recommended, due to an increase in the risk of adverse events.Arbidol has proven to be a safe and well-tolerated treatment for COVID-19 patients. However, it is not associated with a significant reduction in the length of hospital stay. Due to the small number of studies included in this systematic review regarding arbidol, we do not have sufficient evidence to support the use of this drug in patients with COVID-19.


Introduction: It is unknown if the Fontan circulation has an impact on sexual health in men. This study assessed self-reported sexual health and fertility in men with a Fontan circulation.Aims: In this prospective, cross-sectional study, Australian men ≥18 years enrolled in the Fontan Registry of Australia and New Zealand were invited to complete the International Index of Erectile Function (IIEF), alongside questions assessing fertility. These data were compared to historical, age-matched controls.Results: Of 227 eligible men, 54 completed the survey; of those 37 were sexually active and included in the final analysis. Mean age was 28 ± 3 years, age at Fontan was 5 ± 3 years. Fontan type was extra-cardiac conduit in 15 (41%), lateral tunnel in 12 (32%), and atriopulmonary connection (APC) in 10 (27%). Ventricular function was normal in 24 (83%), and all were New York Heart Association Class I  and II . Nine participants (24%) had erectile dysfunction (IIEF-EF score ≤25). The severity was mild (IIEF 22–24) in six (16%), mild–moderate (IIEF 17–21) in two (5%), and moderate (IIEF 11–16) in one (3%). Baseline characteristics and current medication usage were similar in those with and without erectile dysfunction. Compared with historical control values, erectile function was not significantly impaired in the Fontan population (p =0.76). Men with a Fontan circulation had decreased levels of sexual desire and overall satisfaction (p < 0.001). There was no correlation between the presence of erectile dysfunction and any assessed parameter. Eleven (30%) of the cohort reported a pregnancy with a prior partner.Conclusion: In our cohort, overall erectile function was comparable between men with a Fontan circulation and historical controls, however sexual desire and overall satisfaction were reduced. There was no correlation between study parameters and the presence of erectile dysfunction. The proportion of the cohort who had a prior pregnancy was congruent with population data. Since its initial development almost 50 years ago, the Fontan procedure has been increasingly implemented for children who have complex single ventricle cardiac anatomy –4. Over There are numerous long-term morbidities which are well documented complications of a Fontan circulation due to the altered physiological state characterized by systemic venous hypertension, reduced cardiac output, endothelial dysfunction, neurohormonal activation and chronic cyanosis in many . Late covia the Fontan Registry of Australia and New Zealand. A total of 227 patients across all Australian states were identified and contacted between March 2019 and July 2020. A mailed questionnaire was sent to eligible men. If no response was received, they were contacted via telephone and given the opportunity to complete the questionnaire online. The study was approved by the Human Research Ethics Committee at all involved institutions (HREC2019.042).For this prospective, cross-sectional study, men over the age of 18 years who had consented to involvement in research were contacted The survey utilized the International Index of Erectile Function (IIEF), an internationally validated sexual health questionnaire. The IIEF examines the domains of erectile function, orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction. Questions were also included to provide a qualitative assessment of fertility. Patients self-reported appropriate scores for each domain based on their experience in the preceding 4 weeks. The IIEF defines a diagnosis of erectile dysfunction (ED) as an erectile function score of ≤26 (out of a possible 30). Mild ED is defined as an IIEF-EF score of 22–25, mild-moderate 17–21, moderate 12–16, and severe <11. These data were compared with historical control data with mean age of 35 years . Correlations were completed using Spearman rank correlation and Pearson correlation coefficient. All statistical analysis was completed via SPSS v26 for Windows. Statistical significance was based on a Of 227 eligible men, 135 were unable to be contacted or did not complete the survey, 22 were excluded due to a history of mental disorder, 17 refused to complete the survey upon contact, 13 did not have sexual activity during the study period, two declined to have their registry data accessed, and one person died during the study period, leaving 37 men included in the final analysis.p = 0.23). Fourteen patients in total had a history of arrhythmia, eight in the cohort without ED and six in the cohort with ED (p = 0.75). All arrhythmias were atrial in origin.Baseline characteristics are shown in p < 0.001) and overall satisfaction at 8.3 ± 1.9 compared to 9.5 ± 0.8 in controls (both out of 10) (p < 0.001).Patients with a Fontan circulation had significantly decreased levels of sexual desire at 8.1 ± 1.2 compared to 9.1 ± 1.0 (p = 0.76). p < 0.001). Patients with ED also had significantly decreased scores in the domains of orgasmic function (p = 0.05), intercourse satisfaction (p = 0.01), and overall satisfaction (p = 0.01). There was no difference between groups in sexual desire (p = 0.29).As demonstrated in The range of IIEF-EF scores are demonstrated in p = 0.44) and intercourse satisfaction (p = 0.14). There was no association between clinical indices and IIEF-EF . There was no difference in IIEF-EF score between those with APC compared to those with total cavopulmonary connection .There was no difference in orgasmic function (p = 0.85). Of those who did not report a pregnancy, 19 (51%) reported they had only ever used contraception. Four men (11%) reported they had been trying to conceive with a partner for greater than 6 months. There was no difference in IIEF-EF score between the patients who had and those who had not reported a prior pregnancy (p = 0.41). Patients who had an APC Fontan procedure were more likely to report a pregnancy compared to those who underwent a TCPC procedure (p < 0.001).A total of 11 men (30%) in the cohort reported a pregnancy in a prior sexual partner. There was no significant difference in the proportion of those with and without ED who reported a prior pregnancy  literature that ED is typically of mild severity . Prior sMost studies that have examined sexuality in the setting of CHD have included heterogenous CHD types without distinction as to the underlying pathology or anatomy; this is an important consideration for the Fontan population who are affected by unique physiological problems including chronic venous hypertension and reduced cardiac output, especially during exertion. Elevated systemic vascular resistance, chronic cyanosis and cardiovascular drugs including anti-arrhythmics and some diuretics (spironolactone in particular) may also contribute to dysfunction , 22.n = 7) with a Fontan circulation. This study included a questionnaire and interview assessing sexual satisfaction and fertility  were either unable to be contacted or did not complete the survey. A number of these had outdated contact details. Others never returned the survey despite repeated contact. Thus, selection bias is an important consideration. It is feasible that due to the personal nature of the questioning, men with erectile dysfunction may have been less inclined to complete the survey. Men with more significant erectile dysfunction may also have a propensity to avoid sexual intercourse, and thus have been excluded from final analysis once the survey was completed. The overall small number of patients within both cohorts makes it important to consider that the study was underpowered to detect true differences in baseline characteristics between those with and without erectile dysfunction. It is theorized however, that chronic venous hypertension may be implicated in the pathogenesis of sexual dysfunction in men with a Fontan circulation. As our study did not incorporate invasive haemodynamic assessment, we have been unable to assess whether this is contributory.A further limitation to research in sexual health is the reliance on self-reported questionnaires. It is also noted that several different research tools have been used in this area. We utilized the IIEF, as it has a broad base of supporting literature and has been used previously in the field of adult congenital heart disease , 16. OthIn our cohort, erectile function was comparable in men with a Fontan circulation compared with age-matched historical controls, though they did report decreased levels of sexual desire and overall satisfaction. Overall, men with a Fontan circulation reported levels of fertility congruent with that of the general population. Clinicians should be aware that erectile dysfunction may occur in this population and consider asking appropriate questions to ensure that concerns regarding sexual health and fertility are not overlooked.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by HREC Royal Children's Hospital, Parkville, Victoria. The patients/participants provided their written informed consent to participate in this study.RC: concept design, project supervision, and data analysis. IR: assistance with concept design, survey implementation, and data analysis. DT, AB, VW, DB, Yd'U, KP, DK, ML, DZ, and DC: assistance with project design, data interpretation, and manuscript preparation. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The occurrence and prevalence of heart failure remain high in the United States as well as globally. One person dies every 30 s from heart disease. Recognizing the importance of heart failure, clinicians and scientists have sought better therapeutic strategies and even cures for end-stage heart failure. This exploration has resulted in many failed clinical trials testing novel classes of pharmaceutical drugs and even gene therapy. As a result, along the way, there have been paradigm shifts toward and away from differing therapeutic approaches. The continued prevalence of death from heart failure, however, clearly demonstrates that the heart is not simply a pump and instead forces us to consider the complexity of simplicity in the pathophysiology of heart failure and reinforces the need to discover new therapeutic approaches. We will show that despite many approaches having targeted individual/single components of E–C coupling to date, all have shown no benefit and/or differing levels of promise. This suggests a complexity to the current simplicity of thought regarding the treatment of heart failure.This review article will cover the origins of several schools of thought regarding E–C coupling in the failing heart and the treatment of heart failure . We will2+ indicator that can be used in multicellular preparations i, markers of myocardial energy supply, and connective tissue content were quantified. Although weanling animals with POH showed a similar degree of hypertrophy to that found in juvenile animals with POH, there were differences in peak twitch force despite there being no difference in peak [Ca2+]i. Connective tissue content, however, showed significant differences. In weanling animals with POH, connective tissue content was 10 ± 2% compared to 24.0 ± 6.8% in juvenile animals with POH (p < 0.001), which might have contributed to the lower peak twitch force in juvenile animals. Despite a lack of change in connective tissue content or resting [Ca2+]i in weanling animals, passive stiffness in muscles was increased. Lactate dehydrogenase was significantly higher (38%) in weanling animals. However, total creatine kinase activity and total creatine content were significantly less (22%) in hearts from juvenile animals. This study demonstrated that despite having similar levels of hypertrophy, there can be differences in the remodeling of the extracellular matrix (increased fibrosis) as well as molecular remodeling (decrease in the creatine kinase system)  and a prolonged diastolic relaxation. These abnormalities are more pronounced at higher frequencies of stimulation and may be caused by an altered Ca2+ resequestration into the SR. SERCA activity has been reported to be positively correlated with diastolic force. Diastolic force has an inverse relationship with the SERCA activity in failing myocardium. These findings suggested that a reduction in SERCA activity could contribute to both an impairment in systolic as well as diastolic function in failing human hearts [Two of the most significant characteristics of failing human myocardium that have been reported are an increase in diastolic [Can hearts .2+]i availability and myofilament contractile activation is cross-bridge cycling dynamics  might be beneficial in the treatment of heart failure. Studies on isolated muscles from failing human hearts demonstrated a decrease in inotropic response to milrinone . In ordeholidays .2+]i and enhancing inotropy/myocardial contractility in heart failure patients. A simple increase in intracellular Ca2+ was being shown to be clinically detrimental , which may explain in part the failure of the gene therapy trial (CUPID) using SERCA2a in heart failure patients i and SR Ca2+ release were not the sole contributors to heart failure. A novel mutation in TnC was also reported that further strengthened this school of thought  resulted in a further rightward shift in non-failing human myocardium, but did not further shift the Ca2+-force relationship in fibers from failing hearts. Importantly, cyclic guanosine monophosphate (cGMP) resulted in a greater decrease in myofilament sensitivity in fibers from failing hearts. From these studies, it was suggested that not only changes at the level of the thick myofilaments, as previously reported by Leinwand and Bristow i, and there was a change in the Hill coefficient (myofilament cooperativity). These findings indicated that there was a decrease in myofilament Ca2+ sensitivity and a change in cooperativity among thin myofilament proteins most likely reflecting phosphorylation of thin filament regulatory proteins by PKC. Both TnT and TnI have at least two phosphorylation sites. In heart failure tissue, there are two TnT isoforms. These findings might reflect the effect on relative states of phosphorylation of two TnT isoforms. PKC activation, which decreased SR Ca2+ release while decreasing the Ca2+ responsiveness of the myofilaments with a change in cooperativity among thin myofilament proteins, might be a future approach to the treatment of heart failure and Ca2+ regulation in the failing heart. However, the impact of PKC stimulation on vascular smooth muscle remains unclear and must be considered before possible future clinical development  and SR Ca2+ release are key contributors to the pathophysiology of heart failure and possible targets for therapeutic intervention, there is a dynamic state that occurs in the failing heart, especially when blood circulation is impaired and when increases in heart rate can induce a hypoxic milieu [Despite indications that changes at the level of the thick and thin myofilaments and diastolic [Cac milieu ,190,191.c milieu ,193,194.c milieu ,195. Carc milieu ,199,200)O-linked N-acetylglucosamine modification [2+ current, and RyR Ca2+ leak, which facilitate the progression of the above-mentioned diseases [Calcium/calmodulin-dependent protein kinase II (CaMKII) is a serine/threonine kinase that has emerged as a key regulator of cardiac physiology and pathology ,203,204.fication ,206. Excfication ,210,211.diseases ,212. Thediseases ,214. Bendiseases ,216,217.diseases . One readiseases . Future A main upstream regulator of CaMKII is the oxidation at M281/282 by reactive oxygen species (ROS) ,220,221.2+ cycling protein SERCA2a [Despite progress in the clinical management of heart failure, it continues to be associated with a high rate of mortality and morbidity worldwide ,227,228. SERCA2a ,234,235, SERCA2a ,239,240.


The key tumor suppressor protein p53, additionally known as p53, represents an attractive target for the development and management of anti-cancer therapies. p53 has been implicated as a tumor suppressor protein that has multiple aspects of biological function comprising energy metabolism, cell cycle arrest, apoptosis, growth and differentiation, senescence, oxidative stress, angiogenesis, and cancer biology. Autophagy, a cellular self-defense system, is an evolutionarily conserved catabolic process involved in various physiological processes that maintain cellular homeostasis. Numerous studies have found that p53 modulates autophagy, although the relationship between p53 and autophagy is relatively complex and not well understood. Recently, several experimental studies have been reported that p53 can act both an inhibitor and an activator of autophagy which depend on its cellular localization as well as its mode of action. Emerging evidences have been suggested that the dual role of p53 which suppresses and stimulates autophagy in various cencer cells. It has been found that p53 suppression and activation are important to modulate autophagy for tumor promotion and cancer treatment. On the other hand, activation of autophagy by p53 has been recommended as a protective function of p53. Therefore, elucidation of the new functions of p53 and autophagy could contribute to the development of novel therapeutic approaches in cancer biology. However, the underlying molecular mechanisms of p53 and autophagy shows reciprocal functional interaction that is a major importance for cancer treatment and manegement. Additionally, several synthetic drugs and phytochemicals have been targeted to modulate p53 signaling via regulation of autophagy pathway in cancer cells. This review emphasizes the current perspectives and the role of p53 as the main regulator of autophagy-mediated novel therapeutic approaches against cancer treatment and managements. Autophagy, a self-degradative intracellular process, is an essential mechanism of the cell that facilitates renewal or removal of cellular molecules, thereby balancing the cell’s energy consumption and maintaining homeostasis . HoweverTumor suppressor p53 has been implicated in a wide variety of cellular processes, including genomic stability, cell-cycle arrest, DNA repair, apoptosis, cellular senescence, and autophagy . GeneralLiterature-based online databases, Google Scholar, Web of Science, PubMed, Google, and Scopus were accessed to collect information on the published articles that reported molecular mechanism of p53 and autophagy modulation in cancer prevention. Several keywords were used in the search, such as p53, autophagy, cancer, phytochemicals, natural compounds, solid tumors, and lymphomas perspectives role of p53 and autophagy in cancer therapy. Figures were created with the Adobe Illustrator software.The p53 is a central transcription factor that has the capacity to induce diverse cellular responses likely DNA damage repair, cell cycle arrest, apoptosis, and senescence followed by various stress signals  Subbura. The masin vitro and in vivo have signified that the oncogenic activities of p53 mutant variants have heterogeneous which can vary with tissue type in addition to genetic background of the cells  which signify lysosomal-mediated degradation process to facilitate cell survival . It has Accumulating evidence indicated that autophagy could decide whether cancer cells are promoted or suppressed in certain conditions . In thatCell death regulation is a complicated process of maintaining cellular homeostasis by preventing oncogenic growth and recycling damaged cell debris . DysreguThe research to date has found several tumor suppressor proteins and oncogenes to be essential regulators of autophagy. The loss or mutation of these proteins contributes to tumor formation. In addition to being one of these tumor suppressors, the mammalian cell “janitor” p53 may be one of the most frequently mutated genes in human tumors. Most human cancers exhibit p53 mutation, which is found in approximately half of all tumors . P53 actThere are many different cell stressors that might activate p53 . It is p−/− cells, only the cytoplasmic p53 can inhibit autophagy through suppressing AMPK and inducing mTOR, resulting in the hyperphosphorylation of AMPK, TSC2, and acetyl CoA carboxylase (ACC) and hypophosphorylation of mTOR substrate, p70S6K   . microRNant P53) .p-mTOR and increase of p-AMPK , has been described to possess anti-cancer potential through excessive ROS generation and induce p53-dependent apoptotic cell death by autophagy inhibition in cervical cancer (HeLa) and colon cancer (HCT116) cells  cells . Sulfora6) cells . A sterot of p53 .The role of p53 in autophagy regulation in cancer progression has established into a strongly knit, exciting, and rapidly changing disciple in biological science. However, the study of the ability of p53 to modulate autophagy in addition how this modulation of regulation of cancer metabolism raises numerous issues. The basic process of autophagy is important for normal cellular function as its dysregulation is generally encountered during human tumor development . HoweverThe role and impact of modulation of p53 in regulation of autophagy is complex and far from fully clarified. Emerging evidence and rapidly developed omics as well as genome editing techniques have likely been to revolutionized a new p53 roles in autophagic activities of different p53 proteins may vary along with changes in tumor microenvironment. Therefore, novel technologies may shed a new perceptions for a knowledge-based insights to recognize gaps-existing knowledge in addition to analyze scenarios which involve a reconsideration for the function of p53 modulation in autophagy signaling in cancer. Recently, autophagy has been established as a dual role in tumor suppression process likely involved in human cancer research. p53 might be an essential player in the modulation of autophagy pathway, although the exact molecular mechanisms and cellular function in cytoplasmic and nuclear p53-mediated autophagy regulation have not been well studied. However, cellular function and role of p53-mediated autophagy, as well as molecular metabolism in cancer progression, require a strongly related and rapidly altering field. The regulation of cancer metabolism by p53 target genes can diverge according to the stress signal, cell type, and other conditions. Additional, it is evidently established that p53 stabilization is a tumor-specific vulnerability, approaches to indorse the degradation of p53 through autophagy which represents an attractive anti-cancer method. Nevertheless, our augmented understanding of the function of p53 and autophagy will hopefully offer a prospective approach to cancer treatment. Therefore, this review revealed that p53 could be targeted as an important implication of cancer therapy via modulation of autophagy signaling. Hitherto the actual therapeutic use of p53-mediated autophagy induction needs detailed knowledge of how the autophagy-lysosomal pathway may affect in cancer progression.


According to these results, we conclude that there is no evidence to recommend ES in egg-donor IVF cycles, regardless of the number of previous failed cycles.Endometrial scratching (ES) has been proposed as a useful technique to improve outcomes in in vitro fertilization (IVF) cycles, particularly in patients with previous implantation failures. Our objective was to determine if patients undergoing egg-donor IVF cycles had better live birth rates after ES, according to their previous implantation failures. Secondary outcomes were pregnancy rate, clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate, and multiple pregnancy rate. We analysed the results of 352 patients included in the Endoscratch Trial (NCT03108157). A total of 209 were patients with one or no previous implantation failures , and 143 were patients with at least two previous failed implantations . We found an improvement in pregnancy rates (62.9% in group A1 vs. 55.8% in group B1 vs. 70.4% in group A2 vs. 76.4% in group B2,  In 2003, Barash et al. published for the first time their results on patients undergoing endometrial scratching (ES) before an in vitro fertilization (IVF) cycle. They aimed to enhance endometrial receptivity, as this had been seen in guinea pigs when an intentional injury was caused before embryo implantation . They peIn 2019, Vitagliano et al. published a meta-analysis on the impact of ES in infertile women undergoing a first embryo transfer, and they could not find a difference between groups in terms of clinical pregnancy rates (CPR), miscarriage rate (MR), ongoing pregnancy rate (OPR), LBR, multiple pregnancy rate (MulPR), and ectopic pregnancy rate (EPR) in fresh or frozen embryo transfers . The samThe underlying mechanism that would lead to benefits of ES remains uncertain. Some authors have suggested that ES would lead to a better synchronization between embryo and endometrium through the endometrial maturation retardation , while op = 0.823), CPR  and LBR  between intervention and control groups in intention-to-treat (ITT) analysis.It is known that ovarian stimulation may induce an asynchrony between the embryo and the endometrium , due to The definition of RIF has been subject of debate during the last years as it is difficult to determine if a negative result is due to implantation deficient phenomena or to impaired embryo quality. This has led to many different definitions among authors, who may consider recurrent implantation failure from two to six previous failed embryo transfers, with fresh or frozen embryos . In 2014Thus, we performed a subgroup analysis of the outcomes of patients included in the Endoscratch Trial (NCT03108157), dividing our patients into RIF patients (with two or more previous failed implantations) and non-RIF patients (with a maximum of one previous failed embryo transfer) to determine the efficacy of ES in improving live birth rates in egg-donor IVF cycles according to previous implantation failures.The overall number of patients included in the Endoscratch Trial (NCT03108157) was 352, of whom 176 were allocated to receive an ES in the luteal phase of the cycle preceding the embryo transfer cycle (group A), and another 176 to receive no intervention (group B). Sample size was calculated upon egg-donor IVF average pregnancy rates (60%) in order to detect a difference of 15% between the two groups.We performed an analysis according to the number of previous failed embryo transfers, including own egg and donor egg, and fresh and frozen embryo transfers. This secondary analysis of our RCT was not included in the original design of the trial and thus sample size according to the number of implantation failure patients to be included in each arm was not calculated. Out of the 352 patients, 209 had a maximum of 1 previous failed embryo transfer (non-RIF patients), and 143 had at least two previous failed transfers (RIF patients). Among the 209 non-RIF patients, 105 belonged to group A (group A1) and received an ES, and 104 patients belonged to group B (group B1) and did not receive any intervention. Similarly, among the 143 RIF patients, 71 were included in group A (group A2) and 72 in group B (group B2).n = 27 patients excluded).ES was performed as described in the literature, with a biopsy catheter  under abdominal ultrasound guidance . No anaeAll egg donors underwent a conventional antagonist IVF protocol. Eggs were fertilized by ICSI (intracytoplasmic sperm injection) and embryos were kept in culture media until day 5 (blastocyst stage), when embryo transfer was performed. All recipients underwent endometrial preparation with oral  or transdermal oestrogens (oestradiol 100–200 mcg), and vaginal progesterone (400 mcg micronized progesterone every 12 h) was added 5 days before transfer. Treatment efficacy was determined by a transvaginal scan to check the endometrial pattern and thickness, and a blood test to determine oestradiol and progesterone levels on the day of the egg fertilization. Those patients with ovarian activity were prescribed an oral contraceptive pill to help synchronization with their donor, as well as GNRH analogues to induce ovarian quiescence.A positive pregnancy test was considered if β-hCG levels were over 10 mUI/mL 12 days after embryo transfer. CPR was diagnosed if a vaginal ultrasound confirmed an intrauterine gestational sac 4 weeks after the embryo transfer (6th week of pregnancy). IR was calculated by the ratio between the number of gestational sacs observed and the number of replaced embryos. The birth of a living baby beyond the 24th week of pregnancy confirmed a live birth and all pregnancies lost before that moment were considered as miscarriages.Statistical analysis was done using Stata 16 for Windows . We use mean and standard deviation to describe qualitative variables, frequency distribution to summarize qualitative variables and median and 25% and 75% centiles for non-normal variables. Outcomes were analysed with a chi-squared test or Fisher’s exact test.The ES effect is described by absolute and relative frequencies, and the association strength is determined by raw risk ratio (RR) with 95% confidence intervals. A general linear model with a log link and binomial distribution was used to estimate the strength of association between outcomes, adjusted by independent variables. Results are presented as RR and 95% confidence intervals. Statistical significance was considered 0.05 (5% both sides α error) for all comparisons.All groups had similar baseline characteristics in terms of patient age, partner age, smoking habits, body mass index (BMI), race, and previous live births, as is shown in p = 0.164), nor in endometrial preparation duration . Hormonal parameters on the day of egg fertilization were also similar , and a comparable number of extra embryos were frozen in each group after the embryo transfer   .Embryo quality was also similar in the four groups, as is detailed in p = 0.028), but we could not find this difference when we performed a subgroup analysis of the results in the control and intervention groups in non-RIF patients  and RIF patients . In addition, we found no differences when we compared CPR among groups , which confirms that the increase in PR was not clinically relevant. Finally, a total of 55/105 patients in group A and 45/104 patients in group B in non-RIF patients, and 41/71 patients in group A and 40/72 patients in group B in RIF patients had a live birth , which meant no differences in terms of LBR among these populations either, as is detailed in We performed an ITT analysis and we found a lower PR in non-RIF patients  versus non-RIF patients (group A1 and B1), but this difference was not detected when we compared subgroups in the RIF-group (group A2 vs. group B2), which means that this increase is not associated with the ES. Accordingly, our study reveals that there is no difference in CPR and LBR when comparing patients according to whether they have had previous implantation failures or not, both in group A and B. These results are consistent with those of the largest study published in 2019 by Lensen et al. that included own-egg IVF cycles in RIF and non-RIF patients, and subgroup analysis did not find any differences between these groups regardless of whether ES was performed or not . These rIn addition, our results show that patients with RIF have a higher previous miscarriage rate than those who have not suffered previous implantation failures, which may mean that the former had an unknown underlying additional reason for these pregnancy failures.p = 0.00011), PR , and LBR  in those patients who underwent four endometrial injuries during the cycle prior to the embryo transfer [Nevertheless, the possible benefits of ES remain a controversial issue as studies published to date on this subject are very heterogeneous, which entails a real problem when we try to estimate an overall effect. The first study by Barash et al. included RIF and non-RIF patients and found a two-fold increase in IR (27.7% vs. 14.2%, transfer . On the transfer ,23,24. Rtransfer ,26, and transfer ,13,23, otransfer . Most sttransfer , and othtransfer , obtainitransfer ,30,31. IThe main strength of our analysis is that it refers to an RCT including only egg recipients who had homogeneous endometrial preparations and who received good quality embryos. On the contrary, the main limitation is that this subgroup analysis was not considered at the initial study design and thus no randomized stratification was performed and no sample calculation for these subgroups was considered, which may lead to a limited power to establish robust evidence.According to our results, based on the post-hoc analysis of an RCT, ES cannot be recommended as a strategy to improve clinical outcomes in patients undergoing egg donor IVF cycles, regardless of their previous failed treatments. Nevertheless, since our analysis concerns a low number of patients, these conclusions should be taken cautiously and larger studies in egg donor recipients targeting RIF patients should be performed.


TP53 gene, including 19 retrogenes , which are partially active, whereas humans possess only one copy of TP53 and have an estimated cancer mortality rate of 11–25%. The mechanism through which p53 contributes to the resolution of the Peto’s paradox in Animalia remains vague. Thus, in this work, we took advantage of the available datasets and inspected the p53 amino acid sequence of phylogenetically related organisms that show variations in their lifespans. We discovered new correlations between specific amino acid deviations in p53 and the lifespans across different animal species. We found that species with extended lifespans have certain characteristic amino acid substitutions in the p53 DNA-binding domain that alter its function, as depicted from the Phenotypic Annotation of p53 Mutations, using the PROVEAN tool or SWISS-MODEL workflow. In addition, the loop 2 region of the human p53 DNA-binding domain was identified as the longest region that was associated with longevity. The 3D model revealed variations in the loop 2 structure in long-lived species when compared with human p53. Our findings show a direct association between specific amino acid residues in p53 protein, changes in p53 functionality, and the extended animal lifespan, and further highlight the importance of p53 protein in aging.Recently, the quest for the mythical fountain of youth has produced extensive research programs that aim to extend the healthy lifespan of humans. Despite advances in our understanding of the aging process, the surprisingly extended lifespan and cancer resistance of some animal species remain unexplained. The p53 protein plays a crucial role in tumor suppression, tissue homeostasis, and aging. Long-lived, cancer-free African elephants have 20 copies of the  The promise of eternal life has inspired research into this topic across many civilizations and through the millennia, dating back to Herodotus and his writings 2500 years ago. Although the average human lifespan is increasing, our health span appears to be lagging. Several studies argue that the human lifespan is physiologically and genetically limited , yet recTP53 gene and/or in its regulatory pathways [Given the high cancer susceptibility in humans and the role of p53 in regulating cell fate, p53 is regarded as the key regulator of humans’ healthy lifespan ,14. Whenpathways . As revipathways , cancer-pathways . Multiplpathways ,18,19. Fpathways , cell cypathways ,22, apoppathways , ferroptpathways , DNA reppathways , embryonpathways . In the pathways ,28,29. Opathways ,31.TP53 gene is specific for the Holozoa branch, where its ancestral p63/p73-like genes emerged approximately one billion years ago [TP53, TP73 and TP63 genes are rarely mutated in cancers. Yet, the tumor suppressor function of p73 (tp73) is often attenuated in human cancers. The mechanism of suppression is via the hypermethylation of CpG islands at promoter 1, the binding to the overexpressed dominant-negative p73 isoform, dNp73 [From the evolutionary point of view, the ears ago ,33. The ears ago . Unlike m, dNp73 , or to Em, dNp73 . Notablym, dNp73 ,25.CDKN1A (p21) and promyelocytic leukemia protein, PML. The study by Tyner et al. showed that heterozygous mice having one TP53 allele with the deletion of the first six exons  aged prematurely. These mutant mice exhibited enhanced resistance to spontaneous tumors, yet displayed accelerated aging compared to Tp53+/+ mice [TP53 gene. Thus, over-activated p53 per se might not be a critical driver of accelerated aging. Yet, the role of p53′s hyperactivity in aging appears to be conflicting. Fibroblasts derived from hereditary segmental progeroid syndrome patients with the homozygous antiterminating mutation c.1492T > C in the MDM2 gene showed p53 hyperstability and accelerated aging [Mdm2−/− mice show embryonic lethality in a wtp53 background, which indicates that p53 regulation by MDM2 is critical for development. Yet, the conditional deletion of Mdm2 in the epidermis induced p53-mediated senescence and accelerated aging [p53 is a major factor that regulates cellular senescence, and the mechanism is via the activation of cyclin-dependent kinase inhibitor 1 +/+ mice . A study+/+ mice . Based o+/+ mice , as the ed aging . This sted aging . Thus, aCDKN1A. Yet, several other factors contribute to aging, such as the activation of E2F and mTOR, as described elsewhere [Gradual DNA damage and mitochondrial decline are hallmarks of physiological aging. DNA damage that is activated by telomere attrition in an aging cell induces p53 and mitochondrial dysfunction through the repression of the PPARγ co-activator 1α (PGC1α). This induces senescence . Furtherlsewhere . In prinlsewhere .CDKN1A [In addition to full-length p53, p53 isoforms may also play an important role in the modulation of longevity. The expression of certain short and long forms of p53 protein might contribute to a balance between tumor suppression and tissue regeneration . For exaCDKN1A .Considering the critical role of p53 in maintaining tissue homeostasis, high frequency of gain of function (GOF) mutations in cancer, and the limited and conflicting information on p53 role in organismal aging in Animalia, in the present work, we employed currently available datasets and tools to analyze p53 protein sequences in species possessing an extended lifespan. Our thorough analysis depicted a surprising correlation between the changes in the p53 protein sequence and the organismal lifespan, both in short- and long-lived species. Many of the identified changes occurred in the DNA-binding domain and might have a detrimental effect on p53 DNA-binding activity. Overall, we found that, when compared to the majority of closely related organisms within their phylogenetic groups, animals with unusually long lifespans share atypical p53 protein sequence features when compared to human p53 in the position corresponding to the human 180–192 p53 region, which points to the important contribution of loop 2 in the p53 core domain regarding life expectancy.The growing evidence implies that p53 activity might play a pivotal role in aging in humans and little is known about the molecular signatures of extended lifespan in animals including humans; thus, we inspected all currently available sequence data of long-lived animals to explore a link between longevity  and p53 protein sequences. For this, we used the longevity data from the AnAge Database . We mergBalaena mysticetus) from Artiodactyla (subgroup Cetacea), with a maximal lifespan of 211 ± 35 years [Balaena mysticetus had a unique leucine substitution in the proline-rich region, corresponding to amino acid residue 77 in human p53 , which is the only exclusively cave-dwelling chordate, has a maximal documented lifespan of 102 years. A comparison of the p53 protein sequences in amphibians showed a previously unrecognized insertion in Proteus anguinus. The p53 protein from this species had additional serine and arginine residues in the core domain (corresponding to an insertion after amino acid L188 in human p53), which had a deleterious effect on p53 functionality according to the PROVEAN tool  is a long-lived, large, flightless, nocturnal, ground-dwelling parrot that is endemic to New Zealand with a lifespan of around 95 years (TP53 Mutations (PHANTM) classifier, the N131H mutation decreases p53 transcriptional activity by 47.19% [The kakapo (95 years B. Interey 47.19% . In addiMyotis brandtii) is an extremely long-lived bat with a documented lifespan of 41 years [Myotis lucifugus, they had significantly longer lifespans than other bats  and provide a significant exception from Max Kleiber’s law (mouse-to-elephant curve) since their lifespan is extremely long in relation to their small body size [Next, our analysis identified alterations in p53 in species having a long lifespan in the Chiroptera order. The Brandt’s bat ), followed by the goldfish (Carassius auratus (41 years)). The Siamese fighting fish (Betta splendens) had the shortest lifespan in the group (2 years). The correlation analyses show that fifteen amino acid residues in the p53 core domain were significantly associated with a prolonged lifespan (The organisms with the longest lifespan in the Neopterygii dataset were the carp (lifespan A. We fouTerrapene carolina triunguis (138 years)) and the kakapo (Strigops habroptila (95 years)). The green anole (Anolis carolinensis) had the shortest lifespan in the group (7.2 years). The correlation analyses showed that, similar to Neopterygii, a specific fifteen-amino-acid-residue fragment in the p53 core domain was associated with a prolonged lifespan (The lifespans of species in Sauria were significantly variable. The organisms with the longest lifespan in this group were the three-toed box turtle (lifespan A. The molifespan A. SimilaHomo sapiens (122 years)) and the western gorilla (Gorilla gorilla (60 years)). Tarsier (Carlito syrichta) had the shortest lifespan in the group (16 years). The correlation analyses showed that the specific amino acid triad—Q104, S106, L289—was significantly associated with a prolonged lifespan  or histidine (H) at position 104, asparagine (N) at position 106, and phenylalanine (F), serine (S), or tyrosine (Y) at position 289 were associated with short-living primates. While studying human longevity, one needs to consider that the prolonged lifespan of Heterocephalus glaber (31 years) and Castor canadensis (23). The shortest lifespan in the group was Rattus norvegicus (3.8 years). The correlation analyses showed that ten amino acid residues were significantly associated with a prolonged lifespan (The dataset of Glires contained seventeen species with lifespans ranging from 3.8 to 31 years. The organisms with the longest lifespan in this group were lifespan A. Two thMyotis brandtii (41 years)) and the little brown bat (Myotis lucifugus (29 years)). The pale spear-nosed bat (Phyllostomus discolour) had the shortest lifespan (9 years). The correlation analyses showed that nine-amino-acid-long motif was associated with a significantly prolonged lifespan (The organisms with the longest lifespan in the dataset of Chiroptera were the brandt bat (lifespan A.Ursus maritimus) and the panda (Ailuropoda melanoleuca). The shortest lifespan in the group was that of the ferret (Mustela putorius furo). The correlation analyses showed that two amino acids in the p53 core domain, position 148 and 232, were significantly associated with lifespan ) followed by the orca (Orcinus orca (90 years)). Correlation analyses showed that twelve amino acid residues in the p53 core domain were significantly associated with prolonged lifespan  [The changes at the molecular level are often a result of the adaptation of species to environmental forces. To evaluate whether the amino acid residues in the p53 core domains  share some relevant features in relation to the convergent evolution, we constructed a sequential circular representation of the multiple sequence alignments and the mutual information it contains A. The fiturtles) .2+. The loss of Zn2+ triggers the aggregation of L2 and the loss of DNA-binding specificity. The 3D structures of DNA binding domain (DBD) in selected long-lived species revealed intrinsic variations in L2 structure when compared to human p53 (The longest region in p53 that was associated with longevity spanned amino acids in loop 2 (L2) of human p53  and insertions , a complete lack of p53 mRNA expression was found in Turritopsis sp.+-dependent manner and inhibits p53 transcription activity [Cebus imitator, a model organism for studying extreme longevity in primates, where the amino acid sequence is different from all other primate SIRT1s. 3D modeling revealed that the predicted structure of Cebus imitator’s SIRT1 was significantly different from the structures of SIRT1 from Homo sapiens and Sapajus apella (a close relative of Cebus imitator)  .Cebus imitator gained new functions, which might result in the decreased activity of p53 when compared to other primates and slow down the aging processes, most likely via the transient inhibition of p53. Yet, it remains to be elucidated which factors might be affecting the altered target recognition by SIRT1.We hypothesized that SIRT1 from Myotis brandtii (long-living bat described above), in addition to p53, had two atypical protein sequences, one in UFM1  and the other in the p73 .In addition to SIRT1, we investigated other key factors in the p53 pathway. Surprisingly, we found that Recently, it was reported that UFM1 covalently modifies p53; this phenomenon is called UFMylation . UFMylatMyotis brandtii   and in the rest of mammals, including humans, no such extension occurs. We hypothesize that the extended UFM1 protein might contribute to the extreme longevity in myotis bats through the loss of function and consequent changes in p53 protein degradation patterns. Yet, more experimental evidence is needed to draw a clear conclusion.In UFM1, we found an approximately 20-amino-acid-long extension of the C-terminal end in tis) see . In contMyotis brandtii bat (XP_014401672). There were multiple large deletions (>10 amino acid residues) in critical p73 regions, which were found exclusively in this extremely long-lived bat. p73 is the transcription factor that undergoes similar cellular regulation as p53 protein and its role in aging is attributed to the induction of senescence through the upregulation of CDKN1A [Lastly, we found unique changes in the p73 protein sequence in the f CDKN1A .Taken together, our analyses revealed the unexpected correlation between p53 sequence variations and longevity in the animal kingdom. The changes may affect p53 functionality and, thus, influence the activation of replicative senescence, a hallmark of molecular aging. In long-lived species, with no changes in p53, the upstream regulatory proteins, including SIRT1 and UFM1, displayed amino acid changes that may affect their functionality and in consequence alter p53 activity. Yet, further studies are needed to fully comprehend the role of amino acid changes in p53 and its role in the long-lived species described in our work.TP53 is the most often mutated gene in human cancers. On the cellular level, in humans, increased p53 activity protects from cellular stress and enables genome stability, whereas altered mutant p53 protein functionality is essential for cells’ immortalization and neoplastic transformation [Turritopsis jellyfish is immortal and can repeatedly rejuvenate, reverse its life cycle, and thus, was the first and only known “immortal” animal on Earth [Turritopsis sp. [Turritopsis might be directly related to its unique ability of life cycle reversal and “immortality.”The p53 protein is a well-known tumor suppressor and ormation . Howeverormation . The semon Earth . Here, wpsis sp.  and surpTelomere shortening in humans induces replicative senescence, which is a process that is regulated by p53. In the absence of p53, the replicative lifespan of human cells is extended and the concurrent loss of retinoblastoma protein (RB) extends the replicative lifespan to a greater extend (reviewed in ).Intriguingly, our results obtained using Protein Variation Effect Analyzer  show tha2+. We speculate that in long-lived species, L2 affects the p53 binding to DNA and/or other transcription factors and, consequently, affects the replicative senescence program. On other hand, in humans, the L1 region is responsible for p53 binding to the major groove and was reported to undergo the most dynamic changes among the DNA contacting loops (L1–L3) when located on a non-target or target DNA sequence [We identified the 180–192 region, corresponding to the loop 2 (L2) region of human p53, as the longest region that is associated with longevity. The 3D model revealed variations in L2 structure in long-lived species when compared to human p53. Loop 2 is responsible for binding to the minor groove and its structure depends on the presence of Znsequence . Our finCDKN2B-AS1 and IGF2R. The TP53 gene was not among the singled-out variants, which, in accordance with our observations, indicates that no changes in human p53 might be attributing to longevity in humans [Based on what is known about the processes underlying aging, we anticipate that the altered gene expression programs would enable the following changes : (1) morn humans . Our anaSomniosus microcephalus) are available. Compared to other sharks (with a life expectancy of up to seventy years), its lifespan is exceptional. It will thus be very interesting to know the sequence of their p53 protein. A recent study suggests that certain animals may have evolved to have longer lifespans compared to other species belonging to the same taxa [The maximal lifespan according to the AnAge database is attributed to the Greenland shark, with an estimated maximal life span of 300–500 years. Unfortunately, no transcriptomic nor genomic data for the Greenland shark  could act on species with an extended lifespan. In the naked mole rat , which is the longest-living small rodent and weighs only around 35 g, a unique hyperstabilization and nuclear accumulation of the p53 protein were recently reported [Experimental data support our hypothesis that specific p53 variations are associated with longevity. For example, it was found that the reduced expression of the ongevity . It was lifespan . The samlifespan  and a melifespan . In a relifespan . Anotherp53 gene . In thiso stress . In conto stress  in cetacreported . The nakreported . The hypStrigops habroptila, Myotis brandtii, Myotis lucifugus, Proteus anguinus, Balaena mysticetus, and Heterocephalus glaber. It is thus likely that low or no exposure to the UV light promotes the evolutionary changes in the p53 protein structure that alter the p53′s pro-senescence activity. In addition, we speculate that in those species, the endogenous levels of reactive oxygen species might be lower when compared to animals from other, less extreme habitats. This might be a consequence of the changes in the metabolism rates that might affect the overall rate of oxidative phosphorylation and, consequently, slow down the generation of free radical species through the electron transport chain. This hypothesis agrees with the recent study showing that rapamycin, which is a widely studied inhibitor of mTOR, prevents UV-induced skin aging through the inhibition of p53, reversal of UVA-induced cellular senescence, and induction of autophagy [Intriguingly, the animals with extreme longevity that we have identified are mostly nocturnal or live in absolute darkness. These include utophagy .Despite the high complexity of the p53 proteins family, modern methods of comparative genomics provide useful tools for exploring protein variations in closely related species and correlating the extracted molecular information with lifespan . Accordihttps://genomics.senescence.info/species/, accessed on 4 May 2020); AnAge currently contains data on the longevity of more than four thousand animals [To access data on longevity and maximal lifespan, we used the AnAge Database  and merged them with the AnAge Database. We received the p53 sequence information of 118 species with information about their lifespan and sorted them according to their phylogenetic group  [Proteus anguinus (SRX2382497) and Sphenodon punctatus (SRX4014663); the resulting assemblies are enclosed in Transcriptomic data for the bowhead whale was obtained from uly 2020 . When thuly 2020  from theer 2020)  with defhttp://www.phylogeny.fr/alacarte.cgi, accessed on 15 October 2020) [https://phylot.biobyte.de/, accessed on 4 September 2020) and visualized in iTOL (https://itol.embl.de/) [The protein tree was built using the Phylogeny.fr platform (er 2020) ,81 and cer 2020) , which wer 2020)  using ther 2020) ,84. The er 2020) . The reambl.de/) .http://provean.jcvi.org/index.php, accessed on 20 May 2021) [The effect of the p53 variations in long-lived organisms was predicted and statistically evaluated using the Protein Variation Effect Analyzer web-based tool  ,87. PROVay 2021) . All inshttps://www.swissmodel.expasy.org/interactive, accessed on 3 March 2021) [Homo sapiens with bound DNA [We used the SWISS-MODEL template-based approach (ch 2021)  to prediound DNA . The resound DNA . Effectsound DNA .http://www.cbs.dtu.dk/services/SigniSite/, accessed on 22 October 2020) [p-value of ≤0.05. A Bonferroni single-step correction for multiple testing was applied for the global correlation of all sequences, no correction was applied for smaller groups of taxonomically related animals. The manually curated set of 118 high-quality p53 protein sequences obtained from the NCBI  was used as the input file. These sequences were taken from the RefSeq database and the canonical isoform corresponding to the human full-length p53 isoform (NP_001119584.1) was manually filtered for each vertebrate species. The resulting set of these 118 p53 sequences was aligned within the UGENE workflow [http://genomics.senescence.info/species/, accessed on 5 September 2020) [Residue level genotype/phenotype correlations in p53 multiple sequence alignment were performed using SigniSite 2.1 (workflow  and the workflow  with defer 2020) .http://mistic.leloir.org.ar/index.php, accessed on 18 November 2020), with PDB 2ocj (A) as the reference and using default parameters [Multiple sequence alignments of the p53 core domains from 118 species were uploaded to the MISTIC webserver (rameters .TP53 gene gain or losses were inspected using Ensembl Comparative Genomics toolshed [TP53 gene query ENSG00000141510: https://www.ensembl.org/Homo_sapiens/Gene/SpciesTree?db=core;g=ENSG00000141510;r=17:7661779-7687550, accessed on 8 December 2020.toolshed  via EnseMyotis brandtii, Myotis lucifugus, Balaena mysticetus, Heterocephalus glaber, Strigops habroptila, and Proteus anguinus displayed unique p53 protein sequence properties that were not shared with their close relatives that have a shorter lifespan. Altogether, our data show the convergent evolution of p53 sequences supporting a higher insensitivity to p53-mediated senescence under prolonged stress conditions in long-lived vertebrates. Our observations that specific variations of p53 protein are correlated with lifespan provide important grounds for the further exploration of p53 sequences in species displaying extreme longevity. Most importantly, our data implies a general mechanism at work in all vertebrates that leads to extended lifespan, which might be translated to studies on the extension of the health span in humans.This study revealed a previously overlooked correlation between longevity and changes in p53 function due to the amino acid variations in the animal kingdom. Strikingly, several long-lived species, including