bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel actor in mechanotransduction: transient receptor potential cation channel vanilloid (TRPV) 1 in ventilator‐induced lung injury (VILI)
Authors: Michalick Laura , Liedtke Wolfgang , Kuebler Wolfgang M. 
Published: November 2023

Study objectiveMechanical ventilation can damage the lung by causing endothelial barrier failure, edema formation and lung injury. Yet, the exact mechanisms underlying the mechanotransduction at the microvascular barrier are still unclear. In previous work, we had identified a critical role of the endothelial Ca2+ channel transient receptor potential vanilloid 4 (TRPV4) in endothelial barrier failure subsequent to mechanical overventilation. Here, we assessed the relevance of TRPV1 as novel regulator in VILI in vivo, and probed for its contribution to TRPV4‐induced Ca2+ signalling in vivo, ex vivo and in vitro.MethodsWild type, TRPV4‐ or TRPV1‐deficient mice were ventilated for 2 h with low (7 mL/kg) and high (20 mL/kg) tidal volumes (LVT/HVT) in vivo. Endothelial [Ca2+]i in isolated‐perfused lungs, inflated with 5 or 15 cmH2O, and in human pulmonary microvascular endothelial cells (HPMVECs) was quantified by real‐time imaging with or without pharmacological inhibition of TRPV1 and TRPV4, or after activation of TRPV1 and/or TRPV4 by capsaicin and/or GSK1016790A, respectively.ResultsTRPV1 or TRPV4 deficiency or inhibition by either SB366791 or HC‐067047, respectively, attenuated VILI, and reduced the endothelial [Ca2+]i response to high pressure inflation ex vivo, with exception of SB366791 treatment, which only diminished the sustained [Ca2+]i response, but not the initial Ca2+ influx. In vitro Ca2+ measurements from HPMVECs showed a characteristic increase in endothelial [Ca2+]i that in response to selective TRPV4, yet activation of TRPV1 alone had no effect. Dual activation of both TRPV channels, however, amplified and prolong the TRPV4‐mediated Ca2+ influx into HPMVECs.ConclusionsHere, we demonstrate a critical role of TRPV1 as amplifier of TRPV4‐mediated [Ca2+]i response and barrier failure for VILI in vivo, ex vivo and in vitro, and identify a novel signalling axis that may present putative pharmacological targets for the prevention or treatment of ventilator‐associated lung disease.
High‐Fat‐Diet Induced Non‐Alcoholic Fatty Liver Disease and Cardiac Physiology in Mice
Authors: McCarthy Alanna , Luckey Stephen 
Published: November 2023

Non‐alcoholic fatty liver disease (NAFLD) is a serious consequence of high‐fat diet intake and currently affects approximately one third of the world's entire population. Recent evidence suggests that patients with NAFLD have a higher incidence of cardiovascular disease compared to the general population. However, little is known about the link between NAFLD and pathological cardiac remodeling leading to heart disease. Therefore, the objective of this study is to investigate the morphometric and molecular changes associated with the cardiac phenotype resulting from NAFLD induced by a high‐fat diet. In addition, since the Chromosome 18 Chromosome Substitution Strain (CSS‐18) mice have reduced liver disease on a high‐fat diet as compared to the C57BL6 mice, this study aims to determine if CSS‐18 mice are resistant to pathological cardiac remodeling in comparison to C57BL6 mice. Both CSS‐18 and C57BL6 male mice were divided into normal chow diet and high‐fat, low‐sucrose diet groups at 5 weeks of age and administered a diet for 14 days. Morphometric measurements determined that there were no statistically significant differences in heart sizes as measured by heart weight‐to‐tibia length ratio (HW/TL) in either the CSS‐18 and C57Bl6 mice. In order to investigate the molecular changes in the left ventricle following 14 days of diet administration, quantitative PCR was conducted to evaluate the relative gene expression of the sarcoplasmic reticulum Ca2+‐ATPase (SERCA) gene. Expression levels of SERCA were slightly increased by 16% in C57Bl6 mice on a high fat diet whereas SERCA gene expression was not altered in CSS‐18 mice. These investigations suggest although no changes at the morphometric level were determined following 14 days of diet administration, molecular changes at this time are observable. Moreover, these data suggest that there may be differences in gene expression between the CSS‐18 and C57Bl6 mouse strains following diet administration. We are currently conducting additional quantitative PCR analysis of other hypertrophic markers to better understand the molecular changes that may be occurring as a result of NAFLD induced by a high‐fat diet as well as any potential differences between the two mouse strains.Support or Funding InformationMurdock Charitable Trust Start‐Up fundingNadeau Lab at Pacific Northwest Diabetes Research Institute
CXCL4 Aggravates Cardiac Dilation and Mortality after Myocardial Infarction by Inducing Pro‐inflammatory M1 Macrophages and Inhibiting Macrophage Phagocytosis
Authors: Lindsey Merry L. , Jung Mira , Yabluchanskiy Andriy , Cannon‐Stewart Presley L. , Iyer Rugmani Padmanabhan , Flynn Elizabeth R. , DeLeon‐Pennell Kristine Y. , Ma Yonggang 
Published: November 2023

CXCL4 (platelet factor 4) is a pro‐inflammatory chemokine whose deletion attenuates mesenteric ischemia/reperfusion injury in mice. We hypothesized that CXCL4 would exacerbate post‐myocardial infarction (MI) cardiac remodeling and dysfunction. Male C57BL/6J mice (3 to 6 month old) were subjected to permanent coronary artery ligation. CXCL4 gene expression in the infarct region significantly increased from day 3 to day 7 post‐MI, peaking at day 5 (all p<0.05 vs day 0). To investigate the impact of enhancing early CXCL4 levels on post‐MI cardiac remodeling, mice were treated with CXCL4 (25 μg/kg/day) or saline beginning at 24 h post‐MI through osmotic mini‐pump infusion. Saline treated mice showed 47% survival at day 7 post‐MI (7 out of 15), while CXCL4 treatment dramatically reduced survival to 10% (1 out of 10, p<0.05). Because most of the deaths occurred between days 5 to 7 post‐MI, we evaluated day 5 post‐MI. CXCL4 infusion resulted in a 64% increase in CXCL4 protein levels within the infarct region at day 5 post‐MI. Compared to the saline group, CXCL4 treated mice showed significantly higher end‐systolic and end‐diastolic volumes at day 5 post‐MI (both p<0.05), indicating that CXCL4 infusion exacerbated cardiac dilation. Macrophage infiltration into the infarct was similar in both groups at day 5 post‐MI. In vitro, CXCL4 (5 μg/mL, 4 hour stimulation) polarized peritoneal macrophages to a pro‐inflammatory M1 phenotype, evidenced by the upregulation of M1 markers (Ccl3, Ccl5, Il1β, Il6, and Tnfα, all p<0.05) without effect on M2 markers (Arg1, Cd163, Cd206, Tgfβ1, and Ym1). CXCL4 stimulated peritoneal macrophages showed reduced phagocytic potential, as evidenced by fewer uptake of fluorescent E. coli bioparticles compared to control (p<0.05). Impaired phagocytosis after CXCL4 treatment in vivo would inhibit removal of apoptotic cells and debris and impede cardiac wound healing and repair. In conclusion, CXCL4 infusion increased cardiac dilation and mortality post‐MI by inducing pro‐inflammatory M1 macrophages and inhibiting macrophage phagocytosis.Support or Funding InformationThis work was supported by the National Institutes of Health [HL075360, HL129823, and GM114833 to M.L.L., and P01HL051971 and P20GM104357]; the Biomedical Laboratory Research and Development Service of the Veterans Affairs Office of Research and Development Award [5I01BX000505 to M.L.L.]; and American Heart Association [15SDG22930009 to Y.M.].
Coronary Artery Disease Associated Correlation with Decreased Electron Transport Chain Complex Activity
Authors: Blaszak Scott , Ait‐Aissa Karima , Gutterman David D. , Beyer Andreas M. 
Published: November 2023

RationalHeart disease is the leading cause of death worldwide and abnormalities in mitochondrial function are increasingly recognized in association with cardiomyopathy, heart failure, and coronary artery disease (CAD). However, the direct contribution and mechanism of mitochondrial dysfunction on the development of CAD is not fully determined. It has been known for some time that the failing heart relies mostly on glycolysis for ATP production rather than mitochondrial oxidative phosphorylation. Metabolic defects associated with mitochondria are associated with poor cardiovascular outcomes. Currently, the mechanism and role of mitochondrial dysfunction with the development of CAD is not fully understood. We have previously found that mitochondrial DNA damage is significantly elevated in subjects with CAD. However, the functional consequences of these results have not been explored. We hypothesize that in the heart from subjects with CAD, mitochondrial respiration is decreased resulting in decreased mitochondrial ATP production due to defects in the electron transport chain (ETC).MethodsMitochondria from frozen tissue samples of discarded heart tissue from subjects with and without CAD were isolated. Electron transport chain complexes were separated via 5% acrylamide native‐PAGE and stained for specific complex activity (complex II, III, and IV) and total protein level; complex activity measured by substrate conversion was normalized to total protein levels.ResultsOur findings indicate a significant decrease in steady state ATP and NAD+ levels in CAD subjects compared to non‐CAD subjects (Figure 1 A and B). Detailed analysis of complex activity revealed decreased activity in subjects with CAD in complexes I, II, and III (Figure 2). Secondly, analysis of complex IV showed an increase in activity in CAD subjects (Figure 2).ConclusionsOur results suggest a direct correlation between defects in the electron transport chain and coronary artery disease. However, the mechanism of mitochondria dysfunction leading to the development of CAD is currently not understood.Funding Source: National Heart, Lung Blood Institute Training Grant T35 HL072483 (Harder)
Malignant hyperthermia‐associated mutation of RyR1 induces mitochondrial Ca2+ overload in the cardiomyocytes
Authors: O‐Uchi Jin , Mishra Jyotsna , Jhun Bong Sook , Sheu Shey‐Shing 
Published: November 2023

Although human pedigrees carrying the ryanodine receptor type 1 (RyR1) mutations mainly show skeletal muscle disorders including malignant hyperthermia (MH), sudden cardiac death (SCD) in these MH families in the conscious condition without anesthesia are also frequently found in the clinical case studies. However, the molecular mechanism underlying cardiac phenotypes in human MH family is completely unknown. Our group previously reported that a low level of RyR1 is expressed in the mitochondria, but not in the sarcoplasmic reticulum (SR) in the rat and mouse hearts, which serves as an important mitochondrial Ca2+ influx pathway in addition to the mitochondrial Ca2+ uniporter in cardiomyocytes. We also showed, using knock‐in mice carrying a MH‐related RyR1 mutation Y522S (YS) that YS hearts exhibit disrupted mitochondrial morphology as well as compromised mitochondrial functions with a high cellular oxidative state. Moreover, ex‐vivo YS heart developed significantly higher number of multiple ventricular extrasystoles by β‐adrenergic stimulation compared those observed in the wild‐type (WT) hearts. Therefore, our main hypothesis is that YS‐RyR1s form “leaky channel” at mitochondria and induce mitochondrial Ca2+ overload, which alters the cellular Ca2+ handing in cardiomyocyte. Using isolated mitochondria loaded with Ca2+ or membrane‐potential sensitive dyes under the confocal microscope, we found that YS mitochondria have higher basal mitochondrial Ca2+ concentration, depolarized mitochondrial membrane potential. In addition, YS cardiomyocytes exhibit higher basal cytosolic Ca2+ concentration as well as slower cytosolic Ca2+ clearance compared to WT. Finally, pretreatment of RyR1 blocker dantrolene cancelled these changes in YS mitochondria and cardiomyocyes and normalized their Ca2+ handing profiles similar to those in WT. In summary, these results indicate that chronic mitochondrial Ca2+ overload via leaky mutant mRyR1 damages cardiac mitochondrial functions/structures, which may alter cytosolic Ca2+ handling, induce cellular oxidation, and increase the arrhythmogenic events in MH.Support or Funding Information16SDG27260248 AHA Scientist Development Grant
Short‐term Inflammation Increases Proliferative Capacity of Human Skeletal Muscle Progenitor Cells from Young and Old Female Donors
Authors: Blum Jamie , Roman Heather , Thalacker‐Mercer Anna 
Published: November 2023

RationaleWhile short‐term inflammation is required for myogenic progenitor cell (MPC) expansion following damage, chronic or dysregulation of inflammation impairs regenerative capacity. In old (vs. young) skeletal muscle (SkM), the inflammatory response to damage is elevated, which could underlie impaired SkM regeneration observed in older adults. We previously observed that MPCs from older female donors had increased confluency at 240 h in growth medium when proinflammatory cytokine, TNFα, was administered at 96h and maintained for 48 hours (short‐term); this response was not observed when TNFα was administered at earlier or later time points. However, it was unclear whether increased confluence was due to increased proliferation, increased protein synthesis, decreased cell death or some combination of these three. Further, it was unclear whether this response was specific to older MPCs.ObjectivesThe objective was to examine the effects of short‐term TNFα treatment on the proliferative capacity of young and old human female MPCs.MethodsPrimary human MPCs were harvested from SkM biopsies taken from the vastus lateralis of healthy young females (n=6) and healthy old females (n=6). MPCs were cultured in growth medium [(GM), Ham's F12, 20% FBS, 5ng/ml bFGF] for a total of 240 hours. From t=96 to 144 hours a subset of cells were exposed to 10ng/ml TNFα followed by GM (t=144 to 240 hour). % confluence, # of nuclei, and % cell death were tracked using the Celigo® Cell Imaging Cytometer from seeding (t=0) to t=240 hours. Cell cycle phase was determined using BrdU incorporation and Hoechst staining at t=96, 144, 192 hours. qPCR was used to measure the expression of select genes associated with inflammation and myogenesis.ResultsNet area under the confluence curve was significantly increased in TNFα treated cells of only young females at t=144, and of both old and young females at t=192 and t=240 (p<0.05). This was mostly attributed to increased nuclei count, which was increased at t=192 in both young and old MPCs However, old MPCs also had reduced cell death (p<0.05). Further supporting MPC proliferation and potentially commitment in young MPCs, the G2/M phase of the cell cycle was elevated with TNFα treatment at t=144 (p<0.05). Independent of age, TNFα increased the percentage of cells in G0/G1 and reduced the percentage in S phase of the cell cycle at t=240 (p<0.05). Additionally, TNFα treatment increased IL6 expression and reduced IL6 receptor (IL6r) and MyoD expression at t=192 hours (p<0.05) in both older and younger females. Older females had reduced IL6r compared to younger cells at t=192 (p<0.05).ConclusionsShort‐term inflammation promotes progenitor cell expansion and potentially commitment to the myoblast lineage, independent of the age of the MPC donor. Intriguingly the responses to short‐term inflammation may be delayed in MPCs from the older female donors.Support or Funding InformationCornell University
Expression of neuromuscular junction genes in simian immunodeficiency virus infection: impact of chronic binge alcohol and antiretroviral therapy
Authors: Simon Liz , Ray Ishan Basu , Song Kejing , Molina Patricia E 
Published: November 2023

Of the 1.5 million people living with HIV/AIDS (PLWHA) in the United States, approximately 40% have a history of alcohol use disorders. Decreased skeletal muscle mass and function remains a strong and consistent predictor of mortality among PLWHA and occurs at an earlier age among PLWHA compared to the general population. We have previously demonstrated that chronic binge alcohol (CBA) alters gene and microRNA expression and DNA methylation of genes involved in neuromuscular junction function in skeletal muscle obtained at end‐stage of simian immunodeficiency virus (SIV) infection in male rhesus macaques. The aim of this study was to determine whether CBA and/or antiretroviral therapy (ART) altered skeletal muscle expression of genes involved in neuromuscular junction during earlier stages of SIV‐infection in male rhesus macaques. Daily CBA (blood alcohol levels ~50 mM) or sucrose (SUC) administration was initiated 3 months prior to intrarectal SIVmac251 inoculation and continued throughout the study period. Antiretroviral therapy (ART) or placebo was initiated 2.5 months after SIV infection and continued through the study period. Four treatment groups (SUC/SIV±ART and CBA/SIV±ART) were studied at endpoint (11 months post SIV‐infection). Our results demonstrate that CBA and ART decreased expression of brain derived neurotrophic factor (BDNF) in the muscle. SIV increased expression of Acetylcholine receptor gene (AChR) irrespective of CBA or SUC administration in non‐ART treated macaques. However, ART decreased AChR expression to levels similar to controls. No significant changes in the expression of Agrin, Muscle Associated Receptor Tyrosine Kinase (MuSK), Neuregulin, Low‐ Density Lipoprotein Receptor‐Related Protein 4 (LRP4) were detected. We have previously reported that CBA decreases miR‐206 and increases HDAC4 expression in the muscle, and that HDAC4 is a direct target of miR‐206. Expression of BDNF and AChR are reported to be regulated by miR‐206 and/or HDAC4. We hypothesize that the dysregulation of miR‐206‐HDAC4 axis due to CBA potentially plays a role in impairing genes involved in neuromuscular function. Future studies will determine the functional relevance of impaired neuromuscular gene expression and its potential role in compromised skeletal muscle function due to alcohol use in PLWHA.Support or Funding InformationResearch reported was supported by the National Institutes of Health under award numbers P60 AA009803, 1K01AA024494‐01A1
Deletion of claudin‐7 disrupts epithelial cell differentiation in mouse intestines
Authors: Xing Tiaosi , Ding Lei , Camacho Rolando , Chen Yan‐hua 
Published: November 2023

The integrity of intestinal mucosa is vital for nutrition absorption and defense against pathogens. Disruption of intestinal epithelial homeostasis leads to a variety of intestinal disorders, such as chronic inflammation, mucosal ulceration, and cancer. Tight junctions are the physical barrier protecting the body from invasion of intestinal lumen pathogens. As one of the tight junction integral membrane proteins, Claudin‐7 plays an essential role in maintaining intestinal structure and mucosal architecture. To dissect the function of claudin‐7 in intestinal epithelial homeostasis, we used the global (gCldn7−/−) and intestinal‐specific (cCldn7−/−) claudin‐7 knockout mice generated recently as our model systems. Through genome‐wide gene‐expression microarray analysis, immunofluoresent light microscopy, immunohistochemistry, as well as Western blotting analysis, we found that epithelial cell differentiation was greatly altered in claudin‐7‐deficient intestines. For example, enterocytes were dramatically reduced in postnatal day 4 gCldn7−/− and 2–4 months old cCldn7−/− mouse intestines. Goblet cells, Paneth cells, enteroendocrine cells and tuft cells were all significantly decreased in cCldn7−/− mouse small intestines. More importantly, the epithelial cell proliferation in claudin‐7‐deficient intestines was no longer limited to the crypt region and low part of villi where epithelial stem cells and fate‐committed progenitor cells are located. We identified a list of gene expression changes related to cell proliferation and differentiation by microarray analysis between the wild type and claudin‐7‐deficient intestines. These findings suggest that claudin‐7 may have a novel, unidentified function regulating epithelial cell renewal in intestines and play a critical role in maintaining the balance of intestinal epithelial cell proliferation and differentiation.Support or Funding InformationThis study is supported by National Institute of Health grant DK103166.
Extracellular microRNA in age‐related bone loss
Authors: Hamrick Mark 
Published: November 2023

Microvesicle‐ and exosome‐mediated transport of microRNAs (miRNAs) represents a novel cellular and molecular pathway for cell‐cell communication, and previous studies have indicated that specific circulating extracellular microRNAs are associated with osteoporosis and bone fracture. We have investigated the hypothesis that extracellular vesicles (EVs), including exosomes and microvesicles, may contribute to bone loss with aging by transporting specific miRNAs. EVs isolated from bone marrow of aged mice are readily endocytosed by bone marrow stromal (stem) mesenchymal stem cells (BMSCs). Moreover, EVs from aged mice suppress the osteogenic differentiation of BMSCs. We then examined age‐related changes in the miRNAs carried by bone‐derived EVs. These data indicate that the miR‐183 cluster (miR‐183/‐182/‐96) is elevated with age in bone‐derived EVs isolated from different strains of aged mice. In silico analysis reveals that miR‐183 targets Hmox1, and reduced Hmox1 with miR‐183 transfection has previously been shown to increase osteoclastogenesis. We found that miR‐183 can also induce senescence and suppress the osteogenic differentiation of BMSCs, and others have demonstrated that miR‐182 can inhibit the osteogenic differentiation of BMSCs and MC3T3 osteoprogenitor cells. Together these data indicate that aging can significantly alter the miRNA cargo of extracellular vesicles in the bone marrow microenvironment, which may in turn contribute to age‐related bone loss.Support or Funding InformationNational Institute on Aging (NIA AG036675)
For Successful Weight Loss, Counting Calories Matters but Method Might Not
Authors: Foster Jaime Sarah , Gorin Amy , Mobley Amy 
Published: November 2023

To date, many models of weight loss have been deemed successful; however, maintenance remains a challenge. It has been proposed that self‐monitoring is an important behavior in both weight loss and maintenance of weight loss. The purpose of this study was to determine if participant self‐selected form of monitoring calories, (i.e. electronic, paper, or no monitoring) predicted significant differences in weight loss. This study included adults (n=102) enrolled in a standard behavioral weight loss intervention with their partners. For each week a diet record was completed and submitted, participants were given one point, thus higher cumulative scores would indicate more prolonged self‐monitoring. Pearson's correlations were run between percent of weight lost and 1) type of record completed and 2) cumulative number of records submitted. No significant differences were observed between electronic versus paper monitoring. Regardless of calorie monitoring method, the more diet records completed by participants during the course of the intervention was significantly, positively associated with weight loss at week 12 (r= 0.319, p > .001), but there was no association at week 24 of the intervention. Interestingly, calorie monitoring compliance for the first 12 weeks of the program was associated with better weight loss outcomes at 24 weeks (r= 0.237, p <.05). These findings suggest self‐monitoring may be more important during initial behavior change and over time the benefits wane, and it seems that the method of self‐monitoring does not matter. Although this study did not find differences in method of self‐monitoring in weight loss outcomes, it is unknown if there is preferential self‐monitoring method for weight maintenance or if a partner's compliance with self‐monitoring might predict their own success, which will be analyzed upon study completion.Support or Funding InformationThe work was supported by funding from the NHLBI (R21 HL125157)