bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anti‐Tumor Effect of Embryonic Stem Cell Derived Exosomes in Triple Negative Breast Cancer: Potential Role of TCF7‐E‐Cadherin and VEGF
Authors: Samidurai Arun , Das Anindita , Kraskauskas Donatas , Zhang Bei , Olex Amy , Liu Jinze , Hu Bin , Koblinski Jennifer , Singla Dinender K. , Kukreja Rakesh C. 
Published: May 2022

BackgroundTriple Negative Breast Cancer (TNBC) is an aggressive form of cancer and accounts for 10‐20 % of all breast cancer types. TNBC patients are widely treated with chemotherapeutic drugs such as doxorubicin (Dox), which is a primary standard of care. Dox treatment results in unwanted side effects including cardiac dysfunction and skeletal muscle weakness. We previously demonstrated the anti‐tumor effects and cardioprotective effects of embryonic stem cell derived exosomes (Es‐Exos) in the xenograft model of TNBC. The purpose of this study was to identify the biomolecules present in Es‐Exos, which may be linked to the anti‐tumor effects in the xenograft model.Methods and ResultsOrthotopic xenograft model of TNBC was generated by injecting human MDA‐MB‐231‐Tom‐Luc cell line in mammary intraductal T4 region of nude mice. Non‐tumor bearing female mice were used as control (NT‐Con;n=6) as applicable. The animals (n=10/group) were randomized to receive Saline (Con); Dox (5 mg/kg/week); Es‐Exos (50 ug/animal/twice a week; Dox+Es‐Exos; Es‐Exos alone and MEF‐Exos‐(mouse embryonic fibroblast cell derived exosomes 50 ug/animal/twice a week) for up to 4 weeks. Skeletal muscle grip strength declined both in Con and upon treatment with Dox in tumor bearing mice as compared to NT‐Con, which was restored upon treatment with Es‐Exos. Cardiac function measured by echocardiography showed decline in ejection fraction (EF) in saline treated tumor bearing Con and in Dox group, when compared to NT‐Con. Treatment with Dox+Es‐Exos and Es‐Exos improved ejection fraction compared to Con and Dox cohort. Treatment with Es‐Exos significantly reduced the tumor size compared to Dox and saline treated Con groups (Con Vs Dox and Dox+Es‐Exos; p‐value <0.05). Picro Sirius red staining showed increased deposition of collagen in saline treated Con, which was reduced in Dox+Es‐Exos and Es‐Exos groups. RNA seq analysis of Es‐Exos identified several anti‐proliferative genes including a 6‐fold expression of Transcription Factor 7 (TCF7) and 6.5‐fold higher expression of E‐Cadherin (CDH1). Immunohistochemistry analysis of tumor tissue showed abundant expression of VEGF in untreated Con, which was reduced by combined treatment with Es‐Exos and Dox.ConclusionEmbryonic stem cells derived exosomes contain anti‐proliferative genes which may possibly lead to their anti‐tumor property in the TNBC tumor model.
The Role of FXR1 and Senescence in Vascular Biology and Intimal Hyperplasia
Authors: Corbett Cali , St. Paul Amanda , Leigh Tani , Okune Rachael , Preston Kyle , Kelemen Sheri , Autieri Michael 
Published: May 2022

IntroductionDespite the advent of stents, intimal hyperplasia subsequent to vascular interventional procedures remains a major obstacle to success. Vascular smooth muscle cells (VSMC) play a critical role in the development and pathogenesis of intimal hyperplasia indicative of restenosis; therefore regulation of gene expression in VSMC represents a logical intervention point to attenuate this syndrome. FXR1 is a muscle‐enhanced RNA binding protein and expression is increased in injured human and mouse arteries. We have shown that modulation of FXR1 levels affects abundance and stability of inflammatory transcripts in VSMC, suggesting that FXR1 is a negative regulator of inflammation. This drives our hypothesis that FXR1 is involved in mitigating vascular disease and acts as a crucial regulator of inflammatory and proliferative mRNA in VSMC.Approach/ResultsBecause FXR1 expression is increased in injured arteries, we have developed a novel VSMC‐specific conditional knockout mouse (FXR1VSMC/VSMC). In a carotid artery ligation model of intimal hyperplasia, FXR1VSMC/VSMC mice have significantly reduced neointima formation (p<0.001) post‐ligation compared to several controls. To determine the mechanism of these effects, we knocked down FXR1 in human VSMC by siRNA and observed decreased proliferation (p<0.05) as well as an increase in beta galactosidase (p<0.05) and gamma H2AX (p<0.01) staining compared with controls, indicative of senescence. Senescent cells exhibit phenotypic changes called the senescence associated secretory phenotype (SASP) with characteristic gene expression leading to increased inflammation in the tissue microenvironment. RIP‐sequencing demonstrated that FXR1 interacts with transcripts involved in cell cycle control, and RNA stability of these transcripts is decreased with FXR1 KO. qPCR analysis from FXR1 KO mouse VSMC show an increase in transcripts associated with senescence (p21, p16, p53) as well as an increase in SASP‐associated mRNA compared with controls. Furthermore, wild‐type human VSMC cultured in conditioned media from cells transfected with FXR1 siRNA show an increase in SASP mRNA and an increase in proliferation compared with cells cultured in conditioned media from cells transfected with a scrambled control.Summary & ConclusionsOur results are the first to suggest that in addition to destabilization of inflammatory transcripts, FXR1 may stabilize cell cycle related genes in VSMC, and absence of FXR1 leads to induction of a senescent phenotype, an increase in SASP gene expression, and reduction of intimal hyperplasia.
A 14‐3‐3‐mediated mechanism of regulation for the ubiquitin‐sensing kinase TNK1
Authors: Egbert Christina M. , Chan Tsz‐Yin , Lopez‐Palacios Tania , Ashworth Spencer , McCormack Katherine , Vaughan Alec , Andersen Joshua 
Published: May 2022

Thirty ‐eight negative kinase 1 (TNK1) is a poorly characterized member of the ACK family of non‐receptor tyrosine kinases. Previous studies suggest a role for TNK1 in oncogenic transformation; however, the biological function, regulation and substrates of TNK1 remain unknown. We previously discovered that the phospho‐binding protein 14‐3‐3 binds to a phospho‐serine (S502) within a C‐terminal proline‐rich domain of TNK1, sequestering TNK1 in the cytosol and inhibiting its kinase activity. Conversely, the release of TNK1 from 14‐3‐3 activates TNK1 and increases its oncogenic activity1. However, how 14‐3‐3 controls TNK1 localization and activity is still not understood. We recently found that the release of TNK1 from 14‐3‐3 allows TNK1 to interact with ubiquitin‐rich cytosolic condensates, where TNK1 is fully active. Furthermore, we found that the interaction between TNK1 and ubiquitin‐rich condensates requires an unusual ubiquitin association (UBA) domain on the TNK1 C‐terminus that binds with high affinity to K63‐linked poly‐ubiquitin chains. Thus, 14‐3‐3 acts as a toggle to turn on and off the ubiquitin‐binding ability of TNK1, which in turn controls TNK1 oncogenic activation. Our current data suggest that this occurs through a two‐step mechanism. First, the release of TNK1 from 14‐3‐3 activates the TNK1 kinase domain, which leads to an autophosphorylation within the TNK1 UBA domain. Second, this autophosphorylation enhances the affinity of the UBA domain for poly‐ubiquitin, which promotes the clustering of active TNK1 at ubiquitin‐rich condensates where TNK1 phosphorylates downstream substrates.1. Chan and Egbert et al. TNK1 is a ubiquitin‐binding and 14‐3‐3 regulated kinase that can be targeted to block tumor growth. Nat Commun 12, 5337 (2021).
Identifying Mucus‐Degrading Microbes Within the Human Gut Microbiota
Authors: Glover Janiece S. , Ticer Taylor , Engevik Melinda 
Published: May 2022

IntroductionMucus provides a critical barrier for the colonic epithelium by excluding microbes and antigens from direct interaction with epithelial cells, providing a lubricant for stool, and limiting the diffusion of harmful compounds. This barrier function is due in part to the extensive glycan structures found in mucus. Mucin protein is heavily O‐glycosylated with core structures containing α‐ and β‐ linked N‐acetyl‐galactosamine, N‐acetyl‐glucosamine, and galactose. These core structures are elongated and commonly modified by α‐linked fucose, sialic acid and sulfate residues. The sialic acid and sulfate residues protect the underlying mucin glycans from degradation. However, some gut microbes harbor glycosyl hydrolases (GHs) that enzymatically degrade mucin glycans. The released oligosaccharides can then be used as a primary carbohydrate source for the mucus‐associated microbiota. Despite the growing number of bacterial genome sequences available, our knowledge of the mucin‐degrading capacity of human gut commensal microbes remains fragmented. The aim of the present study was to systematically examine the CAZyme mucin‐degrading profiles of the human gut microbiota.Methods & ResultsUsing the CAZy database, we identified 13,156 genomes harboring at least one gene copy of GH families involved in mucin degradation. Commensal microbes were identified using the Human Microbiome Project consortium in the Joint Genomes Institute Integrated Microbial Genomes database, resulting in 4,385 genomes for downstream analysis. Within the Verrucomicrobia phlyum, all Akkermansia glycaniphila and muciniphila genomes harbored gene copies of sialidases (GH33), fucosidases (GH29, GH95), endo‐β‐1,4‐galactosidases (GH2, 35), mucin core GHs (GH84 and GH89), endo‐acting O‐glycanases (GH16), and sulfatases (GH20, GH2, GH42); consistent with their known ability to degrade mucus. Interestingly, the only representative of the Lentisphaerae phylum, Victivallales, harbored a GH profile that closely mirrored Akkermanisa. In the Actinobacteria phlyum, we found that several Actinomadura, Actinomyces, Bifidobacteria, Streptacidiphilus and Streptomyces species contained gene copies of mucin‐degrading GHs. Within the Bacteroidetes phylum, we identified mucin degrading GHs in Alistipes, Alloprevotella, Bacteroides, Fermenitomonas Parabacteroides, Prevotella and Phocaeicola species. Firmicutes contained Abiotrophia, Blautia, Enterococcus, Paenibacillus, Ruminococcus, Streptococcus, and Viridibacillus species with mucin‐degrading GHs. Far fewer mucin‐degrading GHs were observed in the Proteobacteria phylum, with only 3‐4 GHs families found in Klebsiella, Mixta and Enterobacter. We confirmed the mucin‐degrading capability of 26 representative gut microbes by growing these bacteria in a chemically defined media lacking glucose supplemented with porcine intestinal mucus.ConclusionsThese data greatly expand our knowledge of mucin degradation within the human gut microbiota.
Higher Levels of Shear Stress Downregulate Endothelin‐1 mRNA Expression
Authors: Rodriguez Carmen , Garcia Mario , Cabral Shelsea , Conde Daniel , Gurovich Alvaro N. 
Published: May 2022

BackgroundPhysical inactivity has been shown to be a risk factor in the development of endothelial dysfunction. Endothelin‐1 (EDN‐1), a potent vasoconstrictor contributes to the pathogenesis of cardiovascular disease. Exercise‐induced endothelial shear stress (ESS) is a mechanical stimulus caused by alterations in blood flow patterns that regulates vascular function. Although it has been reported that higher levels of ESS may act as a protective mechanism to prevent vascular dysfunction, the role of pulsatile exercise‐induced ESS with varying exercise intensities has not been explored. Therefore, the purpose of this study was to determine the effects of pulsatile exercise‐induced ESS based on in vivo exercise intensity on EDN‐1 expression.MethodsCommercially available human umbilical vein endothelial cells (HUVEC; Sigma‐Aldrich, St Louis, MO) were cultured until 90–100% confluence. Exercise‐induced ESS in vivo was obtained from our previous reports. Cultured HUVEC cells were exposed to pulsatile resting ESS (18 dynes/cm2) for 2 hours, followed by 1 hour at resting ESS, low‐intensity exercise‐induced ESS (35 dynes/cm2), moderate exercise‐induced ESS, or high‐intensity exercise‐induced ESS (75 dynes/cm2) on a closed circuit pump and channeled slide (Ibidi pump system (PumpControl Software 1.5.4) and slides, Ibidi Inc., Fitchburg, WI). A set of cells were exposed to physiologically low shear stress levels (10 dynes/cm2) for 3 hours as a control. Total RNA was extracted and reverse transcribed followed by measurement of EDN‐1 mRNA expression via qRT‐PCR. qRT‐PCRs were performed in duplicates and changes in gene expression were calculated using the ΔΔ‐CT method with GAPDH used as the normalizing control gene. Statistical analysis was performed using graphpad prism 8 software (Graphpad Software.). Significance was considered at p<0.05.ResultsEDN‐1 mRNA expression was significantly downregulated following low and high intensity exercise‐induced ESS compared to resting conditions (p<0.05). Moderate intensity exercise induced ESS showed a trend downregulation in EDN‐1 mRNA expression compared to resting conditions (p<0.10).ConclusionsOur data suggests that higher levels of pulsatile exercise‐induced ESS are needed to suppress mRNA expression of EDN‐1. Although moderate intensity exercise induced ESS showed only a trend difference in mRNA expression compared to resting conditions, we have previously reported that moderate exercise‐induced ESS was shown to upregulate endothelial nitric oxide gene expression, a key vasodilatory enzyme that may prevent vascular dysfunction.
Ameliorative Effect of Morinda Lucida on L‐nitro Arginine Methyl Ester (L‐name) Induced Hypertension in Male Wistar Rats
Authors: Ogunpolu Blessing S. , Omobowale Temidayo , Rauff Barakat , Oyagbemi Ademola , Falayi Funke , Hassan Fasilat 
Published: May 2022

Hypertension is a chronic cardiovascular disease of extreme and important global concern. It has been established as a leading cause of death especially in humans. The aim of this study was to evaluate the possible antihypertensive effect of a common locally available plant Morinda lucidaagainst L‐Nitro‐Arginine‐Methyl‐Ester (L‐NAME)‐induced hypertension in male Wistar rats.Forty‐eight rats were used for the experiment. They were divided into six groups labelled A‐F, each containing eight animals. The animals were dosed for six weeks with group A being the control group (normotensive) given feed and water ad libitun; Group B animals were administered L‐NAME only, 40 mg/kg (hypertensive); Groups C, D and E were simultaneously treated with L‐NAME (40 mg/kg) and Morinda lucida extract in increasing doses of 100 mg/kg, 200 mg/kg and 400 mg/kg, respectively, while Group F were given lisinopril at 20 mg/kg for a period of 6 weeks. From the result, there was significant increase in systolic, diastolic, and mean arterial blood pressure in the hypertensive group compared to the normotensive group and hypertensive treated groups. Hypertension caused significant (p<0.05) increases in oxidative stress markers, including malondialdehyde (MDA), protein carbonyl (PC), hydrogen peroxide (H2O2), while reducing the activities of superoxide dismutase (SOD), and serum nitric oxide (NO) levels. Also, serum myeloperoxidase (MPO), blood urea nitrogen and creatinine were increased with high expression of cardiac injury biomarkers such as cardiac troponin and angiotensin 2 type 1 receptor. These indicated oxidative stress, cardiac damage because of hypertension, most especially in the untreated hypertensive group. The co‐treatment of hypertensive rats with Morinda lucida extract caused reduction in markers of oxidative stress and inflammation and normalized blood pressure parameters. The findings from this study suggest the possibility of using Morinda lucida extract as a novel antihypertensive agent.
TNK1 negatively regulates TBK1 at ubiquitin condensates
Authors: Lopez‐Palacios Tania , Egbert Christina M. , Chan Tsz‐Yin , Ashworth Spencer , Vaughan Alec , Andersen Joshua 
Published: May 2022

Thirty‐eight‐negative kinase 1 (TNK1) is a poorly understood member of the ACK family of non‐receptor tyrosine kinases. TNK1 has been linked to oncogenic activity. However, the biological function of TNK1 remains unclear. Recently, we discovered the presence of a functional ubiquitin association (UBA) domain on the C‐terminus of TNK1, which is an unusual feature on a kinase. Previously, we demonstrated that the TNK1 UBA domain binds to poly‐ubiquitin with high affinity and with no preference for length or linkage type (1). Interestingly, deletion of the UBA domain (TNK1 ΔUBA) affects TNK1 intracellular localization and decreases its phospho‐substrates network. Based on these data, we hypothesized that the UBA domain homes TNK1 to substrates. To test this hypothesis, we used quantitative phospho‐tyrosine proteomics in pro‐B cells transformed with either TNK1 or TNK1 ΔUBA to identify UBA‐dependent TNK1 substrates. Among the putative UBA‐dependent substrates, we identified phospho‐Y235 of TANK‐binding kinase 1 (TBK1). TBK1 is an important serine/threonine protein kinase involved in the regulation of inflammation, autophagy, and NF‐kB signaling. Through confocal microscopy, we demonstrated a colocalization between TNK1 and TBK1 at p62‐positive phase‐separated clusters of ubiquitin—referred to here as ubiquitin condensates. We found that TNK1 localizes to ubiquitin condensates in a UBA‐dependent manner. Furthermore, our data suggest that TBK1 is inhibited by phosphorylation at Y235, as phospho‐null mutation at Y235 (Y235F) significantly increases phosphorylation of the TBK1 substrates p62 and OPTN. We also found that CRISPR/Cas9 deletion of TNK1 increased TBK1 activity and phosphorylation of p62 and OPTN. These data suggest that TNK1 negatively regulates TBK1 activity. Intriguingly, we also identified an enrichment of other putative UBA‐dependent TNK1 substrates in the NF‐kB signaling pathway, suggesting that the UBA domain tethers TNK1 to multiple substrates in this pathway, perhaps as a means to dampen NF‐kB signaling. Our current work focuses on the biological impact of these phosphorylations on NF‐kB activity, inflammatory signaling, and autophagy.1. Chan, TY., Egbert, C.M. et al. TNK1 is a ubiquitin‐binding and 14‐3‐3‐regulated kinase that can be targeted to block tumor growth. Nat Commun 12, 5337 (2021).
Disruption of ATG9A‐dependent basal autophagy causes an accumulation of ubiquitin‐rich condensates which act as a platform for inflammatory signaling
Authors: Jayatunge Dissanayake Arachchilage Dasun N. , Andersen Joshua L. , Poole Daniel M. , McEwan Colten M. 
Published: May 2022

Excessive inflammation underlies many human diseases, such as neurodegeneration, autoimmune disorders, cancer, and COVID‐19. Thus, cellular mechanisms that control inflammation are of high therapeutic interest. Autophagy has been implicated in the suppression of inflammation, yet mechanistic links between autophagy and inflammation are not completely understood. Previous work demonstrated that loss of ATG9A, but not ATG5 or ATG7, increased inflammatory signaling through the STING‐IRF3 cascade, suggesting that perhaps an autophagy‐independent function of ATG9A regulates inflammation.1 Here, we show that loss of the essential basal autophagy regulators ATG9A and ATG101 sensitizes cells to dsDNA‐induced IRF3 activation. Importantly, this effect was not observed with the loss of ATG5 or ATG7, suggesting that the canonical LC3‐lipidation autophagy machinery is not required for suppression of IRF3 and inflammatory signaling.2 In an effort to understand the role of ATG9A and ATG101 in suppressing inflammatory signaling, we found that loss of ATG9A and ATG101, but not ATG5 or ATG7, caused an accumulation of ubiquitin‐rich condensates. We also found that the accumulation of ubiquitin‐rich condensates coincided with an overactivation of the ubiquitin‐sensing, IRF3‐targeted kinase TBK1. Importantly, we found that inhibiting the accumulation of ubiquitin‐rich condensates via knock‐out of p62/SQSTM1 abrogated the increased inflammatory signaling caused by loss of ATG9A. Together, our data suggest a model in which the loss of basal autophagy machinery causes an accumulation of ubiquitin‐rich condensates, which, in turn, act as a platform for the aberrant activation of TBK1‐mediated inflammatory signaling. We propose that these data have important implications for diseases of protein aggregation wherein similar ubiquitin‐rich condensates form and aberrant inflammatory signaling plays a pathological role.References(1) Saitoh, T.; Fujita, N.; Hayashi, T.; Takahara, K.; Satoh, T.; Lee, H.; Matsunaga, K.; Kageyama, S.; Omori, H.; Noda, T.; Yamamoto, N.; Kawai, T.; Ishii, K.; Takeuchi, O.; Yoshimori, T.; Akira, S. Atg9a Controls DsDNA‐Driven Dynamic Translocation of STING and the Innate Immune Response. PNAS 2009, 106 (49). https://doi.org/10.1073/pnas.0911267106.(2) Kannangara, A. R.; Poole, D. M.; McEwan, C. M.; Youngs, J. C.; Weerasekara, V. K.; Thornock, A. M.; Lazaro, M. T.; Balasooriya, E. R.; Oh, L. M.; Soderblom, E. J.; Lee, J. J.; Simmons, D. L.; Andersen, J. L. BioID Reveals an ATG9A Interaction with ATG13‐ATG101 in the Degradation of P62/SQSTM1‐ubiquitin Clusters. EMBO reports 2021, 22 (10). https://doi.org/10.15252/embr.202051136.
Genomic Rearrangement in Non‐coding Region of Chromosome 1 Leads to Spontaneous Obesity and Heart Failure with Preserved Ejection Fraction
Authors: White Donnell D. , Wu Jian , Lauterboeck Lothar , Kesterson Robert , Yang Qinglin 
Published: May 2022

BackgroundObesity is a global epidemic leading to shorter life expectancies for the first time in recent U.S. history, and epidemiological studies predict that half of the U.S. adult population will be obese by 2030. Obesity is the most common comorbidity and risk factor for heart failure (HF) in patients with preserved ejection fraction (HFpEF), a subclass containing more than 50% of HF cases. However, effective treatment of HFpEF remains scarce due to the incomplete understanding of the mechanisms. Our lab discovered a spontaneously obese mouse line, with a genomic rearrangement in a non‐coding region of chromosome 1. Most monogenic obesity animal models exploit the hypothalamic leptin–melanocortin feeding pathway. However, monogenic models are not representative of most human metabolic disease. This obesity animal model may better represent the numerous contributing mechanisms of obesity in humans, allowing us to find better solutions to help prevent further decline of health outcomes in the US.MethodsA mouse line (C57/B6J) of Floxed‐stop Overexpression of IF1 (FEI) was generated and maintained for Cre‐mediated conditional IF1 overexpression. We observed that severe obesity became a fixed phenotype in inbred FEI mice after inbreeding for 5‐6 generations. Targeted‐Locus‐Amplification (TLA) analyses revealed that FEI inbreeding triggered a genomic rearrangement in a non‐coding region of chromosome 1. In the present study, we focus on assessing the metabolic and cardiac phenotype of FEI mice using echocardiography, histology, glucose and insulin tolerance assays, and exercise tolerance tests.ResultsEarly onset obesity was consistent in FEI mice with increased peripheral fats and circulating tissue lipids, as well as reduced systemic metabolic rates. FEI mice also exhibited increased food intake, fasting blood glucose, insulin, and leptin with impaired glucose and insulin tolerance as early as 6 weeks of age. Echocardiography revealed that the FEI mice developed concentric left ventricular hypertrophy with preserved ejection fraction. However, E/A ratio results from Doppler flow measurement at mitral valve suggest diastolic dysfunction in the FEI mice. Heart weight:tibial length was increased in FEI compared to WT. H&E and Trichrome blue staining on heart sections exhibited increased cardiomyocyte hypertrophy and cardiac fibrosis. H&E of adipose tissue and liver revealed increased adipocyte size, and increased fat deposition, respectively. FEI exhibited significantly decreased exercise tolerance compared to WT.ConclusionsWe conclude that the metabolic and cardiac phenotypes in the FEI mice closely recapitulate obese patients who suffer from HFpEF. Further studies on these mice should yield novel and translational insight into the genetic and metabolic mechanisms underlying the development of obesity and HFpEF, improving patient treatments.