bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary nitrate supplementation attenuates the mechanoflex in older women with early menopause: A pilot study
Authors: Manabe Kazumasa , Yoo Jeung‐Ki , Takeda Ryosuke , Curtis Bryon , Roberts‐Reeves Monique , Fu Qi 
Published: May 2022

Women who reached early menopause (EM, 40‐44 yrs) have a greater risk for cardiovascular disease than women with normal menopause (NM, 50‐54 yrs), which may be attributed to a longer duration of estrogen loss and a greater reduction in nitric oxide bioavailability in both the peripherals and center. Previous studies have shown that dietary nitrate supplementation improves cardiovascular function in older women, but how autonomic neural control changes in daily living, such as during exercise, has been involved is unclear. We examined the hypothesis that 2wks continuous use of dietary nitrate supplements would attenuate the exercise pressor reflex in older women with EM.Six EM (65±4 [SD] yrs) and 8 NM (64±2 yrs) women participated in this randomized, placebo‐controlled, double‐blind, cross‐over pilot study. All subjects underwent 2 wks of beetroot juice (BRJ; 140 ml containing ~800 mg nitrate per day) or placebo (140 ml nitrate‐depleted BRJ, daily) intervention with ≥14 days of wash‐out. Before and after each intervention period, subjects performed SHG using the dominant hand at 40% of maximum voluntary contraction (MVC) until fatigue, followed by 2 min of PECA with an upper arm cuff inflated to 250 mmHg. Heart rate (HR; ECG), blood pressure (BP; finger photoplethysmography), muscle sympathetic nerve activity (MSNA; microneurography), and respiration (capnography) were continuously measured. In addition, 24‐h ambulatory BP standard deviation (SD) was monitored before and after each intervention (an indication of BP variability).There were no differences in baseline HR, BP and MSNA, MVC, and the time to fatigue between the EM and NM groups before and after intervention (all p>0.05). At the first 30 s of SHG, the EM group showed significant decreases in MSNA burst frequency (DBF; ‐4.5±6.5 in EM vs. 2.5±6.2 bursts/min in NM, p=0.065) and burst incidence (DBI; ‐10.6±12.6 vs. 2.6±8.4 bursts/100 heartbeats, p=0.037) after BRJ intervention compared with the NM group (Figure1A and B). However, there were no differences between groups at fatiguing exercise and during PECA after the intervention. The interventional changes in 24‐h diastolic BP SD had a positive correlation with ΔMSNA BF (r=0.55, p=0.053) and BI (r=0.58, p=0.036) at the first 30 s of SHG in all subjects and EM individuals were in the left‐lower area (Figure2 A and B).These results suggest that dietary nitrate supplementation may attenuate and mechanoreflex, but not the metaboreflex, in older women with EM during static hand grip, which has a relation with BP variability during ambulation. Certainly, these preliminary observations need to be verified in more older women in future studies.
Identifying Novel Signaling Mechanisms Downstream of Gq‐Coupled Receptors
Authors: Loomis Joseph F. , Chandan Naincy R. , Brody Matthew J. , Smrcka Alan V. 
Published: May 2022

The G protein alpha subunit G□q is a critical mediator of cells’ response to a variety of external stimuli as a result of activation of Gq‐coupled GPCRs. G□q‐dependent signaling influences an array of physiological processes, including neurotransmission and vasoconstriction; additionally, dysregulated G□q‐dependent signaling has been firmly linked to several pathologies, including uveal melanoma and maladaptive cardiomyocyte hypertrophy. One established mechanism by which activated G□q subunits might promote these processes involves activation of phospholipase C beta isoforms (PLC□), which catalyze the hydrolysis of PI(4,5)P2 into inositol (1,4,5) trisphosphate (IP3) and diacylglycerol (DAG), ultimately leading to Ca2+ mobilization and protein kinase C activation. However, G□q subunits also signal independently of PLC□, through p63RhoGEF and Trio, for example.To identify novel G□q targets that might be involved in Gq‐driven pathologies, we conducted a proximity biotinylation proteomic screen in HEK293A cells comparing wild‐type G□q and constitutively active G□q Q209L each fused to TurboID, a promiscuous biotin ligase. This approach enabled the high‐confidence identification of numerous proteins that were selectively enriched in cells expressing G□q‐Q209L‐TurboID compared to cells expressing G□q‐WT‐TurboID. These enriched proteins included known G□q interactors (PLC□, Trio, and GRK2); however, scattered among these known interactors were several proteins that have not been previously shown to interact with active G□q, including SPRED1, SMARCD3, YAP1, BCAS2, and HDAC9.Our initial efforts have focused on SMARCD3, a regulatory component of the SWI/SNF chromatin remodeling complex. To test for SMARCD3 interactions with G□q, we expressed SMARCD3 in COS‐7 cells and found that SMARCD3 selectively inhibits G□q‐stimulated, but not G□□‐stimulated, PLC□ activity, indicating that SMARCD3 competes with PLC□ for access to active G□q. In addition, we expressed SMARCD3 in HEK293A cells and found that (1) SMARCD3 co‐immunoprecipitates with G□q and (2) interacts with G□q in a nanoluciferase fragment complementation assay.SWI/SNF regulates gene transcription by modulating chromatin accessibility. Given that Gq signaling regulates gene expression in both physiological and pathological systems, we will assess the impact of SMARCD3 knockdown in cellular models of G□q‐driven transcription and cell function. Ultimately, we will expand this approach to test other top hits' ability to interact with and potentiate signaling downstream of active G□q. Through these endeavors, we aim to uncover novel G□q signaling mechanisms and inform therapeutic strategies for combatting pathologies marked by aberrant G□q signaling.
Interactions between β3‐adrenergic receptors and bFGF‐induced effects in rat aortic smooth muscle cells
Authors: Chang Yingzi , Dagat Lei Alena , Yusuf Aisha , Zahriya Yusuf , Staputyte Kotryna , Worley Emma , Holt Alex , Canuteson Natalie , Messieha Vereena , Halila Kasey 
Published: May 2022

BackgroundBasic fibroblast growth factor (bFGF)‐mediated vascular smooth muscle cell (VSMC) proliferation and migration play an important role in vascular injury‐induced neointima formation and subsequent vascular restenosis, a major event that hinders the long‐term success of angioplasty. The function of β3‐adrenergic receptors (β3‐ARs) in vascular injury‐induced neointima formation has not yet been defined.ObjectivesOur current study explored the possible role of β3‐ARs in vascular injury‐induced neointima formation by testing its effects on bFGF‐induced VSMC migration and proliferation.Methodsβ3‐AR expression in rat carotid arteries was examined at 14 days following a balloon catheter‐induced injury. The effects of β3‐AR activation on bFGF‐induced rat aortic smooth muscle cell proliferation, migration, and signaling transduction (including extracellular‐signal‐regulated kinase/ mitogen activated protein kinase, ERK/MAPK and Protein kinase B, AKT) were tested.ResultsWe found that vascular injury induced upregulation of β3‐ARs in neointima. Pretreatment of VSMCs with a selective β3‐AR agonist, CL316,243 significantly potentiated bFGF‐induced cell migration and proliferation, and ERK and AKT phosphorylation. Our results also revealed that suppressing phosphorylation of ERK and AKT blocked bFGF‐induced cell migration and that inhibiting AKT phosphorylation reduced bFGF‐mediated cell proliferation.ConclusionOur results suggest that activation of β3‐ARs enhances bFGF‐mediated effects on VSMCs by interacting with bFGF‐mediated ERK and AKT phosphorylation and β3‐ARs may play a role in vascular injury‐induced neointima formation.
Run for Your Life: A Meta‐Analysis of the Effects of Exercise Intensity on Cardiovascular Outcomes in a Rat Model of Hypertension
Authors: Meredith Kayla M. , Luckey Stephen W. 
Published: May 2022

ObjectiveHypertension increases the risk of pulmonary embolism, stroke, heart attack, and death. To prevent these events in hypertensive patients, regular exercise has been recommended as a nonpharmacological intervention for decades, but it is still not well understood whether cardiovascular benefits vary with exercise intensity. In this meta‐analysis, we explored the effect of treadmill running intensity on systolic blood pressure (SBP), mean arterial pressure (MAP), and resting heart rate (RHR) in a rat model of hypertension, known as spontaneously hypertensive rats (SHR).MethodsA SciFinder Scholar database search returned 817 comparative studies, of which 72 (1505 rats) were included for quantitative analysis. Studies were characterized as low, moderate, or high intensity based on treadmill speed setting or, where available, %VO2max. Aggregate means and standard errors for SBP, MAP, and RHR were extracted and subjected to one‐way ANOVA with post‐hoc Tukey’s test using GraphPad Prism 9.ResultsWhen compared to sedentary hypertensive controls, both low and moderate‐intensity treadmill exercise yielded significant reductions in SBP, MAP, and RHR, but high‐intensity exercise did not. Although the greatest improvement in SBP, MAP, and RHR resulted from low‐intensity treadmill exercise, no statistically significant difference was found between training intensity levels for these cardiovascular outcomes.ConclusionsLow and moderate‐intensity, steady‐state treadmill sessions over several weeks reduced blood pressure and resting heart rate in hypertensive subjects. The failure of high‐intensity exercise to improve cardiovascular outcomes may suggest a role played by oxidative stress and merits further investigation. Overall, these preliminary results suggest that even low‐intensity exercise may serve as a beneficial tool that positively impacts cardiovascular outcomes in chronic hypertension.
Pyrazole Reduces the Effects of Oxidative Stress in Cardiomyocytes Induced by Rotenone and Doxorubicin
Authors: Shum Alika , Ara Hosne , Bess Ezra , Colvin Chase , Sharma Sudha , Murru Siva , Panchatcharam Manikandan , Miriyala Sumitra 
Published: May 2022

BackgroundIn the United States, cardiovascular disease accounts for approximately 1 in every 4 deaths. One factor that has been identified as a source for the development of cardiovascular disease is oxidative stress in the mitochondria of cardiomyocytes. Oxidative stress is a condition where the number of reactive oxygen species (ROS) is greater than the number of antioxidants. The consequences of oxidative stress in cardiomyocytes include tissue damage through cell death and the formation of 4‐hydroxynenal (4‐HNE) aggresomes through lipid peroxidation. These known effects have led to this study in which we determined the antioxidant function of a synthetic drug called pyrazole. We specifically tested the antioxidant property of two pyrazoles known as S9 and S10 in the HL‐1 cardiomyocyte cell line.MethodsOxidative stress was induced by using a compound known as rotenone and a chemotherapy agent known as doxorubicin (DOX). Both have been found to cause cardiotoxicity partly due to their ability to induce oxidative stress within cardiomyocytes. MitoSOX®and high pressure liquid chromatography (HPLC) were used to measure mitochondrial superoxide production. Immunocytochemistry (ICC) was used to measure the formation of 4‐HNE aggresomes. Western blot analysis was used to measure the expression of the antioxidant enzyme manganese‐dependent superoxide dismutase (SOD2). Seahorse XF24 analyzer was used to measure oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) to determine mitochondrial function.ResultsDOX and rotenone induced mitochondrial superoxide production was found to be reduced in cells treated with S9 or S10. From ICC, S9 and S10 treatments showed reduced formation of 4‐HNE aggreosomes compared to the level of 4‐HNE aggresome formation following treatment with DOX or rotenone alone. Western blot analysis results confirmed that both S9 and S10 were capable of restoring expression of SOD2 which was reduced by rotenone or DOX in HL‐1 cells. Seahorse analysis showed that cells treated with either DOX or rotenone and either S9 or S10 resulted in increased OCR, ATP turnover, reserve capacity, and glycolysis & glycolytic reserve capacity compared to the cells treated with rotenone or DOX alone.ConclusionThe results from our study indicate that pyrazoles S9 and S10 have the ability to reduce the oxidative stress in cardiomyocytes and therefore have the potential to serve as therapeutics for cardiovascular disease.
Intestinal Epithelial PTPN2 Restricts Adherent‐Invasive E. coli Colonization and Promotes Anti‐Microbial Peptide Responses in Mice
Authors: Chatterjee Pritha , Spalinger Marianne , Shawki Ali , Santos Alina , Gries Casey , Sayoc Anica , Canale Vinicus , Crawford Meli'sa , Lei Hillmin , Borneman James , McCole Declan 
Published: May 2022

BackgroundIn addition to a physical barrier, the intestinal epithelium generates a chemical barrier to the luminal microbiota by secreting various antimicrobial factors. Alterations in the gut microbiota and expansion of pathobionts such as adherent‐invasive Escherichia coli (AIEC) are associated with inflammatory bowel disease (IBD) pathogenesis. Our previous work showed, mice deficient for the expression of the IBD risk gene, Ptpn2, exhibit pronounced expansion of a novel murine adherent‐invasive Escherichia coli (mAIEC) strain. This study aimed to investigate how PTPN2 expression in intestinal epithelial cells restricts mAIEC colonization in vivo.MethodsWe generated tamoxifen‐inducible, intestinal epithelial cell‐specific knockout mice (Ptpn2∆IEC). Ptpn2∆IEC and control littermates (Ptpn2fl/fl) were infected with either PBS, non‐invasive E. coli K12, or fluorescent‐tagged mAIEC (mAIECred)for 4 consecutive days. After euthanasia, bacterial colonies were enumerated in mouse tissues. mRNA and protein expression were assayed in intestinal epithelial cells (IECs) by PCR and Western blot.ResultsPtpn2∆IEC mice exhibited intestinal region‐specific higher mAIECred ‐ but not K12 ‐ bacterial load in distal colon tissue compared to Ptpn2fl/fl mice (P=0.038; n=9‐12). To identify if the higher susceptibility to mAIECred infection was associated with altered host defenses, we measured levels of anti‐microbial peptide (AMPs) in these mice. Ileal RNA expression of the alpha‐defensin AMPs, Defa5 and Defa6, were significantly lower (P=0.008, 0.0182 respectively; n=3‐5) in Ptpn2∆IEC vs. Ptpn2fl/fl mice, after mAIECred infection but not K12 infection. Further, expression of the protease matrilysin‐7 (MMP7) ‐ which is responsible for the proteolytic cleavage of alpha‐defensins – was significantly decreased in ileum and distal colon of Ptpn2∆IEC mice post mAIECred infection compared to Ptpn2fl/fllittermates (P=0.042, 0.007; n=4‐6). REG3γ, an AMP that acts largely against gram‐positive bacteria, was unchanged in all conditions. However, ileal IEC lysozyme protein expression was lower in PBS and K12, but not mAIECred, infected Ptpn2∆IECmice (P= 0.067, 0.0165 respectively; n=8) compared to control Ptpn2fl/fl mice.ConclusionIntestinal epithelial PTPN2 plays a major role in regulating intestinal bacterial defenses and gut regional variations in pathobiont colonization.
Monoamine Receptor and Transporter Interaction Profiles of 4‐Alkyl‐Substituted 2,5‐Dimethoxyamphetamines
Authors: Luethi Dino , Rudin Deborah , Hoener Marius C. , Liechti Matthias E. 
Published: May 2022

BackgroundVarious ring‐substituted phenethylamines and amphetamines are used recreationally due to their mind‐altering effects. Furthermore, such psychedelic substances have recently gained increased interest as prospective therapeutics. Here, we studied the pharmacological properties of 4‐alkylated 2,5‐dimethoxyamphetamines in vitro. Specifically, we assessed the effect of the 4‐alkyl chain length on interactions with monoaminergic targets. We aimed to test the hypothesis that the derivatives with the highest clinical potency display the most potent serotonin (5‐HT) type 2A receptor interactions, which is the key driver of psychedelic effects.MethodsWe determined binding affinities of 2,5‐dimethoxyamphetamine (2,5‐DMA), 4‐methyl‐2,5‐dimethoxyamphetamine (DOM), 4‐ethyl‐2,5‐dimethoxyamphetamine (DOET), 4‐butyl‐2,5‐dimethoxyamphetamine (DOBU), and 4‐amyl‐2,5‐dimethoxyamphetamine (DOAM) at serotonergic, adrenergic, and dopaminergic receptors and transporters, as well as at the trace amine‐associated receptor 1 (TAAR1). For this, we assessed radioligand displacement using cell membrane preparations expressing the respective targets. Furthermore, we determined the functional activity of the derivatives at the 5‐HT2A and 5‐HT2B receptors by measuring calcium mobilization and at the TAAR1 by measuring cAMP accumulation. In addition, we assessed whether any of the derivatives inhibit transporter‐mediated uptake of radiolabeled monoamines.ResultsUnlike 2,5‐DMA, its 4‐alkylated derivatives displayed potent (i.e., nanomolar) affinity at 5‐HT2A and 5‐HT2C receptors. Increasing length of the 4‐alkyl chain increased the selectivity for 5‐HT2A vs. 5‐HT1A and 5‐HT2C receptors. Whereas DOM and DOET activated the 5‐HT2B receptor as partial agonists in the nanomolar range (EC50: 68–128 nM, Emax: 73–85%), DOBU and DOAM did not activate the receptor at investigated concentrations (EC50 > 10,000 nM). In contrast to the potent interactions with 5‐HT2 receptors, the 4‐alkyl‐substituted 2,5‐dimethoxyamphetamines did not or only weakly (i.e., in the micromolar range) interact with other monoaminergic targets.ConclusionAmong the tested substances, user reports suggest DOM and DOET to be the only derivatives with a distinct psychedelic effect profile. Our data therefore indicate that 5‐HT2A and 5‐HT2C receptor affinity alone is not a sufficient predictor for the clinical and psychedelic potency of 4‐substituted 2,5‐dimethoxyamphetamines. To assess the clinical potential of the tested substances, future studies should focus in more detail on pharmacokinetics and qualitative differences in 5‐HT2 receptor activation.
Detection of prohibited growth factors (GFs) in doping control: serum concentration ranges in a reference population of athletes
Authors: Botre Francesco , de la Torre Xavier , Donati Francesco 
Published: May 2022

Growth factors (GFs) are a wide class of polypeptides that can regulate cellular proliferation, migration and differentiation. Due to their ability to extensively impact on tissue regeneration, the use of GFs in sports is currently prohibited in and out of competition and included in the 2022 List of Prohibited Substances of the World Anti‐Doping Agency (WADA). At present, methods of detection of prohibited GFs for doping control purposes have been developed exclusively for recombinant Growth Hormone (recGH) and Insulin‐like growth factor1 (IGF‐1).Since GFs are endogenously produced substances, their abuse can be detected by fixing “reporting threshold” to differentiate their normal, physiological levels and the exogenous administration. Such a strategy imposes the determination of “normality ranges” for the athletic population.We considered the principal banned GFs, that are fibroblast growth factor (FGF), platelet‐derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF), measuring their levels – including those of their major isoforms – in 92 serum samples, collected from elite athletes in the framework of doping control tests. Preliminarily, we confirmed all the above considered growth factors are actually measurable in serum, defining also their respective limits of detection. Furthermore, we were able to identify differences in concentration levels possibly related to gender and age. Finally, we established normal serum concentration ranges, that can be used as reference normal population values necessary to fix threshold values able to discriminate the physiological levels and the recourse of doping practices.
Suppression of MT1 and Melatonin Treatment Improves Liver Phenotypes in Mdr2‐/‐ mice
Authors: Ceci Ludovica , Wu Nan , Carpino Guido , Chen Lixian , Zhou Tianhao , Kennedy Lindsey , Kyritsi Konstantina , Francis Heather , Franchitto Antonio , Onori Paolo , Gaudio Eugenio , Glaser Shannon , Alpini Gianfranco 
Published: May 2022

Background & AimPrimary Sclerosing Cholangitis (PSC) is a cholestatic liver disease characterized by hepatic fibrosis and portal inflammation. Melatonin is synthesized by arylalkylamine N‐acetyltransferase (AANAT) in the pineal gland, as well as extrapineal sites such as cholangiocytes. We previously found that: (i) the MT1 receptor is primarily expressed in cholangiocytes with low and absent expression in hepatic stellate cells and hepatocytes, respectively; (ii) melatonin reduces biliary proliferation via MT1 receptor signaling; and (iii) melatonin treatment for 1 wk decreases biliary proliferation and liver fibrosis in bile duct ligated rats by downregulation of MT1 and clock genes (PER1, CRY1, CLOCK and BMAL1). We aimed to evaluate the beneficial effects of long‐term melatonin treatment and MT1 signaling on biliary phenotypes, liver fibrosis and portal inflammation in Mdr2‐/‐ mice (a model of PSC).MethodsMale FVB/NJ and Mdr2‐/‐ mice had access ad libitum to drinking water with/without melatonin for 3 months. We evaluated: (i) ductular reaction (DR) by immunohistochemistry (IHC) for CK19, (ii) liver fibrosis by Sirius Red staining and (iii) portal inflammation by IHC for F4/80. MT1, AANAT, and clock genes immunoreactivity was evaluated by immunofluorescence (IF) co‐stained with CK19 and qPCR in isolated cholangiocytes. Male C3H‐Hej (WT for MT1‐/‐), FVB/NJ (WT for Mdr2‐/‐), MT1‐/‐, Mdr2‐/‐ mice and MT1‐/‐/Mdr2‐/‐ (DKO) mice were euthanized at 12 wk of age. We analyzed: (i) MT1 expression by IF and mRNA expression in total liver by qPCR to validate our model; (ii) liver damage by H&E, DR by IHC for CK19 and liver fibrosis by Sirius Red staining and (iii) portal inflammation by IHC for F4/80 and expression of the inflammatory markers by qPCR in total liver.ResultsLong‐term melatonin treatment reduces DR, liver fibrosis and portal inflammation in Mdr2‐/‐mice. Prolonged administration of melatonin in Mdr2‐/‐mice improves liver phenotype by decreasing the immunoreactivity of MT1, AANAT and clock genes in Mdr2‐/‐ mice, which suggests the chronobiotic action of melatonin on biliary circadian rhythm. DKO mice have no MT1 expression and display ameliorated liver phenotype compared to Mdr2‐/‐ mice.ConclusionWe demonstrated that chronic melatonin treatment improves liver histology and restores the biliary circadian rhythm by interaction with MT1. Suppression of MT1 receptor in Mdr2‐/‐mice ameliorates biliary/liver phenotypes through changes in clock genes and AANAT. Restoration of the circadian rhythm by modulation of melatonin/MT1 signaling may be key for the management of cholangiopathies.