bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retinoic acid modulation guides human-induced pluripotent stem cell differentiation towards left or right ventricle-like cardiomyocytes
Authors: Zhang Hengliang , Sen Payel , Hamers Jules , Sittig Theresa , Dendorfer Andreas , Merkus Daphne 
Published: May 2024

Background: Cardiomyocytes (CMs) induced from human induced pluripotent stem cells (hiPSCs) by traditional methods are a mix of atrial and ventricular CMs and other non-cardiomyocytes. Retinoic acid (RA) plays an important role in regulation of the spatiotemporal development of the embryonic heart. Aim: Create engineered heart tissue (EHT) with left and right ventricular phenotype from hiPSCs by intervening with specific concentrations of RA during hiPSC differentiation towards CM. Methods: hiPSC were derived by reprogramming skin fibroblasts and erythroid progenitors. Different concentrations of RA (Control without RA, LowRA with 0.05 μM and HighRA with 0.1 μM) were administered during third to sixth days of the differentiation process. EHTs were generated by assembling CMs derived from hiPSC (hiPSC-CM) at high cell density in a low collagen hydrogel. EHTs were further matured and grown in a customized biomimetic tissue culture system, that provides continuous electrical stimulation, medium agitation and stretch. Finally, RNA extraction and tissue fixation were performed on CMs and EHTs for RT-qPCR and immunofluorescence staining analysis, while RNA sequencing was conducted on EHTs to examine how RA affects gene expression associated with function and structure of EHTs. Results: HighRA-hiPSC-CMs exhibited highest expression of maturity genes MYH7 and cTnT. The expression of TBX5, NKX2.5 and CORIN, which are transcription factors associated with left ventricular development, was also the highest in the HighRA-hiPSC-CM. The expression of TBX5 and NKX2.5 was also found to be highest in the HighRA-EHTs, while expression of right ventricular transcrition factors TBX20 and ISL1 was highest in control-EHTs. RNAseq of EHTs showed augmented extracellular matrix gene expression in HighRA-EHTs. The HighRA-EHTs were functionally most similar to left ventricle with the highest contraction force, the lowest beating frequency, and the highest sensitivity to hypoxia and isoprenaline. Conclusion: By interfering with the differentiation process of hiPSC with a specific concentration of RA at a specific time, we were able to successfully induce CMs and EHT with a phenotype similar to that of the left ventricle or right ventricle. Our research paves the way for future studies on in vitro left ventricular or right ventricular function, personalized drug screening, and precision medicine. German Center for Cardiovascular Research (DZHK81Z0600207 to D.M. and P.S.) China Scholarship Council (CSC202108410141) and Henan Provincial Medical Science and Technology Research Project. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Piezo2 sensory innervation during kidney development
Authors: McLarnon Sarah , N’Guetta Pierre , Tassou Adrien , Geron Matan , Scherrer Gregory , O'Brien Lori L 
Published: May 2024

Piezo2 is a mechanically activated ion channel expressed in a subset of sensory neurons, including in the bladder. Our lab has recently mapped innervation of the developing kidney and found that renal nerve development begins at embryonic day 13.5 (E13.5) and is tightly aligned with smooth muscle actin (SMA+) arterial development. However, the presence and spatiotemporal innervation of Piezo2+ sensory nerves in the kidney remains unknown. In the current study, we hypothesized that Piezo2+ sensory nerves would be present early in kidney development adjacent developing nephrons and that these axons innervating the kidney could be traced back to Piezo2+ cell bodies in the dorsal root ganglia (DRGS). To test this hypothesis, we performed immunofluorescent staining to label all nerves (Tubb3+, pan-neuronal marker) and Piezo2 in kidneys from wildtype mice at early (E13.5), mid (E15.5) and late (post-natal day 0, P0) nephrogenesis. To determine the signaling pathways of Piezo2+ nerves in the kidney to the peripheral nervous system (PNS), we utilized retrograde tracing with a Cre-driven fluorescently (pAAV-Flex-tdTomato) labeled virus injected into the kidney of heterozygous Piezo2Cre/+ adult mice (n=4, 10 weeks). The injected kidney, the contralateral control, and cervical to sacral DRGs were collected and fluorescent imaging was performed with confocal microscopy. We found that by E15.5, Piezo2+ sensory nerves were present in the developing kidney which constitute a small subset of all nerves (Tubb3+). These Tubb3+Piezo2+ sensory nerves persist through nephrogenesis (P0) and in the adult mouse kidney. Piezo2+ sensory nerves were found in nerve bundles running along SMA+ vasculature as well as observed adjacent glomeruli (Nphs2+) and proximal tubules (Lrp2+). Importantly, we also identified Piezo2+ sensory nerves in the renal cortex from human kidney samples. Retrograde tracing experiments revealed Piezo2+ sensory nerves in the kidney originate from lower thoracic and lumbar DRGs. Taken together, these data suggest that Piezo2+ sensory nerves are present in the mouse and human kidney and are capable of transmitting signals back to the PNS. As Piezo2 is known to be expressed in juxtaglomerular cells, Piezo2+ sensory nerves observed in close proximity suggests a previously unrecognized kidney cell-nerve crosstalk. Future studies will investigate Piezo2+ sensory activity and feedback in the kidney to understand the role of Piezo2 in renal mechanosenstion. NIH R01DK121014 to LO. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
CD8 T cells exert a critical role in the transition from left heart failure to lung remodeling and right ventricular hypertrophy
Authors: Wang Dongzhi , Weng Xinyu , Chen Yingjie 
Published: May 2024

Chronic left ventricular (LV) failure or heart failure (HF) often progress to pulmonary remodeling and right ventricular (RV) hypertrophy even with optimal medical care. Cytotoxic CD8+ T cells play an important role in modulating virus infection and tissue injury by producing proinflammatory cytokines and cytolysis of the infected or injured cells. However, the role of CD8+ T cells in heart failure (HF)-induced lung remodeling and RV hypertrophy is unknown. To determine the role of CD8 T cells in modulating HF progression under preexisting HF conditions, wild type mice with existing LV failure produced by transverse aortic constriction (TAC) were randomized to depletion of cytotoxic CD8+ T cells, regulatory T cells (Tregs), or both by using specific blocking antibodies. The cardiac function, lung inflammation, fibrosis, vascular remodeling, and right ventricular remodeling were determined. As anticipated, LV failure caused lung inflammation and activation of pulmonary CD4+ T cells and CD8+ T cells. Interestingly, depletion of CD8+ T cells dramatically attenuated the increase of lung weight, lung inflammation, lung vascular remodeling, and RV hypertrophy in mice with existing LV failure. LV failure was associated with an increased ratio of activated T cells to Tregs, and Treg depletion exacerbated lung inflammation and the progression of LV failure. Treg depletion also exacerbated the lung CD4+ and CD8+ T cell infiltration, and the percentage of effector memory T cells (Tem) in HF mice. Depletion of CD8+ T cells was suffcient to rescued HF mice from the exacerbated lung inflammation and the progression of LV failure that was caused by Treg depletion. These findings demonstrate that CD8+ T cells play a critical role in promoting the transition from LV failure to lung remodeling and RV hypertrophy. NIH funding. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
CD8+ T cells mediate kidney fibrosis in diet-induced obese mice
Authors: Erickson John , Edell Claudia , Walker Savannah , Colson Jackson , Pollock Jennifer 
Published: May 2024

Diet-induced obesity (DIO) is an epidemic in the United States and globally. Obesity is well known to exacerbate and/or promote kidney disease. Inflammation is a major factor in DIO and kidney disease. Utilizing a 20-week DIO mouse model (45% fat) and a normal diet (ND; 10% fat), our lab previously showed greater kidney medullary interstitial fibrosis as well as increased kidney medullary CD3+ T cells in DIO mice when compared to ND mice. Specifically, we found increased kidney CD8+ T cells, but similar CD4+ T cells, in DIO mice compared to ND mice. We hypothesized that CD8+ T cells in DIO mice are a primary factor in promoting kidney interstitial fibrosis. DIO mice were treated with anti-CD8 antibody or control anti-IgG antibody and ND mice were treated with control anti-IgG antibody for the final two weeks of the DIO protocol (n=7-9). DIO/anti-IgG and DIO/anti-CD8 mice had significantly higher body weight than ND/anti-IgG mice as expected (one-way ANOVA; p<0.0001). Administration of anti-CD8 treatment in DIO mice had null effects on body weight (one-way ANOVA, p=0.509) and kidney weight (one-way ANOVA; p=0.067). Utilizing flow cytometry, we verified that anti-CD8 treatment significantly reduced CD8+ T cells compared to anti-IgG in the kidney (one-way ANOVA; p=0.0077; DIO/anti-IgG vs DIO/anti-CD8, p=0.0066) and in the blood (one-way ANOVA; p=0.0034; DIO/anti-IgG vs DIO/anti-CD8, p=0.0048). Using Picrosirius Red histological staining to assess kidney fibrosis, we found that anti-CD8 treatment significantly blunted kidney medullary fibrosis (one-way ANOVA, p=0.0177, ND/anti-IgG vs DIO/anti-IgG, p=0.0329; DIO/anti-IgG vs DIO/anti-CD8, p=0.0318), whereas glomerular fibrosis was not affected by anti-CD8 treatment in DIO mice (one-way ANOVA, p=0.31). Urine was collected in 12-hour increments and analyzed for markers of kidney damage. All groups of mice showed similar urinary KIM-1 excretion (one-way ANOVA; p=0.62) and protein excretion (one-way ANOVA; p=0.69). DIO mice with anti-CD8 or anti-IgG treatment had significantly increased urinary NGAL excretion compared to ND mice (one-way ANOVA; p=0.0203). In summary, anti-CD8 treatment reduced circulating and kidney CD8+ T cells, as well as kidney medullary interstitial fibrosis but not urinary NGAL excretion. These results indicate that CD8+ T cells mediate kidney medullary interstitial fibrosis in a 20 week DIO mouse model. Funding: R01 DK134562, R25 DK115353, F31HL167626. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Fenoldopam-mediated increase in autophagy associates with recruiting WIPI2 protein in early endosomes in vascular smooth muscle cells
Authors: Polzin Jacob , Lu Amy , Amatya Bibhas , Armando Ines , Jose Pedro , Lee Hewang 
Published: May 2024

Autophagy, a crucial cellular homeostatic process, has protective roles in the pathogenesis of hypertension. Dopamine, a monoamine neurotransmitter, regulates autophagy in the kidney and vascular system. However, the exact roles and mechanisms of dopaminergic system on the regulation of autophagy is not well known. In rat aortic vascular smooth muscle cells, fenoldopam (FEN, 25 nM/15 min), a D1-like receptor agonist, increased the ATG5 and LC3-II (a late autophagosome maker) protein expression. Consistently, FEN decreased p62/SQSTM1 protein expression. The FEN-mediated increase in ATG5 was attenuated by SCH39166 (1 μM/15 min), a D1- like receptor antagonist, indicating that FEN increased autophagy in the autophagosome formation stage through its D1-like receptors. FEN increased the protein expression of WD Repeat Domain, Phosphoinositide Interacting 2 (WIPI2) in a concentration- and time-dependent manner, which is important in the early steps of autophagosome formation. FEN (25 nM, 15 min) increased the WIPI2 puncta fluorescence intensity and the colocalization of WIPI2 with EEA1 (Veh: 7.12±1.1% vs FEN: 9.96±0.9%, N=5, P < 0.001, Student’s t test), a typical phosphatidylinositol-3-phosphate binding protein in early endosomes, indicating that WIPI2 recruitment in early endosomes is important in the early stage of FEN-mediated autophagic process. Taken together, FEN increases autophagy with WIPI2 recruitment in the early endosomes in vascular smooth muscle cells. This work was supported by US National Institutes of Health grants R01DK134574 and R01DK119652. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Availability of receptors for advanced glycation end-products (RAGE) influences differential transcriptome expression in mice exposed to chronic secondhand smoke
Authors: Van Slooten Ryan , Curtis Katrina , Kirkham Maddie , Chang Ashley , Arroyo Juan , Reynolds Paul 
Published: May 2024

The receptor for advanced glycation end-products (RAGE) has a central function in orchestrating inflammatory responses in multiple disease states. RAGE is a transmembrane pattern recognition receptor with particular interest in lung disease due to its naturally abundant pulmonary expression. Our previous research demonstrated an inflammatory role for RAGE following acute exposure to secondhand smoke (SHS). However, chronic inflammatory mechanisms associated with RAGE remain unclear. In this study, we assessed transcriptional outcomes in mice exposed to chronic smoke in the context of RAGE expression. RAGE knockout (RKO) and wild type (WT) mice were exposed to SHS five times weekly via a nose-only delivery system (Scireq Scientific, Montreal, Canada) for six months and compared to mice exposed to room air (RA) only. Total lung RNA was isolated using the Direct-zol RNA MiniPrep kit (Zymo Research, Irvine, CA) and mRNA was purified using poly-T oligo-attached magnetic beads. Synthesis of cDNA, library construction, and sequencing was performed using standard approaches. We specifically compared the phenotypic and environmental conditions from WT+RA, WT+SHS, and RKO+SHS mice. Preprocessing and analysis of RNA-sequencing gene expression data included read trimming, mapping and quantifying the reads to transcripts, and calculating significant differentially expressed genes. The results of these analyses were summarized and compared via Venn diagrams, volcano plots, and functional gene cluster enrichment analysis. Notable gene clusters were specific to cytoskeletal elements, inflammatory signaling, and ciliogenesis. Finally, gene ontologies (GO) demonstrated significant biological pathways that were differentially impacted by the presence of RAGE. These data collectively identify several opportunities to further dissect RAGE signaling in the context of SHS exposure and foreshadow possible therapeutic modalities. This work was supported by funding from the National Institutes of Health (NIH 1R15-HL152257). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
The multi-omic response to exercise training across rat tissues: interactive tools for data dissemination through the MoTrPAC data hub
Authors: Lindholm Malene E , Zhen Jimmy , Amar David , Gay Nicole R , Jean Beltran Pierre M , Yu Jay , Samdarshi Mihir 
Published: May 2024

The Molecular Transducers of Physical Activity Consortium (MoTrPAC) aims to map the molecular responses to exercise and training to elucidate how exercise improves health and prevents disease. The first MoTrPAC data provides an extensive temporal map of the dynamic multi-omic response to endurance training across multiple rat tissues. All results can be viewed, interrogated, and downloaded in a user-friendly, publicly accessible data portal ( https://motrpac-data.org ). The MoTrPAC data compendium includes transcriptomics, proteomics, metabolomics, phosphoproteomics, acetylproteomics, ubiquitylproteomics, DNA methylation, chromatin accessibility, and multiplexed immunoassay data. This compilation of 211 datasets across 19 tissues, 25 molecular assays, and 4 training time points in adult male and female rats constitutes 19 terabytes of data. Over 35,000 analytes were found to be differentially regulated in response to endurance training, with many displaying sexual dimorphism. We observed a male-specific recruitment of immune cells to adipose tissues and an anticorrelated transcriptional response in the adrenal gland related to the stress response. Temporal multi-omic and multi-tissue integration demonstrated similar temporal responses in the heart and skeletal muscle, reflecting a concerted adaptation of mitochondrial biogenesis and metabolism. Integrative multi-omic network analysis revealed connections between the heat shock-mediated stress response and mitochondrial biogenesis. Training increased phospholipids and decreased triacylglycerols in the liver, and there were extensive changes to mitochondrial protein acetylation. Many changes were relevant for human health conditions, such as non-alcoholic fatty liver disease, inflammatory bowel disease, cardiovascular wellness, and tissue damage and repair. Altogether, this MoTrPAC resource provides an unprecedented view of the effects of exercise across an organism, revealing mechanistic details of how exercise impacts mammalian health. The MoTrPAC data hub is the primary online resource to disseminate this large scale multi-omics data. The MoTrPAC Study is supported by NIH grants U24OD026629 (Bioinformatics Center), U24DK112349, U24DK112342, U24DK112340, U24DK112341, U24DK112326, U24DK112331, U24DK112348 (Chemical Analysis Sites), U24AR071113 (Consortium Coordinating Center), U01AG055133, U01AG055137 and U01AG055135 (PASS/Animal Sites). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Differential Distribution and Expression of α1-adrenergic Receptors in Low Shear Stress Induced Neointimal Formation
Authors: Cooper Kathryn , Taylor Mark 
Published: May 2024

Low fluid shear stress in conduit arteries has emerged as a determinant of neointimal formation—an accumulation of vascular smooth muscle cells on the surface of the intima—the most challenging component of atherosclerosis to treat. α1-adrenergic receptor (α1-AR) antagonists have been well evaluated in vascular injury models yielding reduced neointimal formation. However, the α1-AR subtypes’ (α1A-AR, α1B-AR, α1D-AR) role in neointimal formation have not been determined under low shear stress conditions. α1-AR subtypes are expressed in various tissues and evoke different responses to the same ligand resulting in both adaptive and maladaptive responses. This study was designed to identify and characterize the α1-AR subtypes in low shear stress induced neointimal formation. An in vivo partial ligation mouse model was utilized to actuate low fluid shear stress and create neointimal formation in the left carotid artery in 14 days. The right carotid artery remained uninjured as the control. For tissue collection and processing, the left and right carotid arteries were harvested, snap-frozen in liquid nitrogen, and cryosectioned. Immunofluorescence staining was performed using primary antibodies for α1B-AR or α1A-AR and CD31 (endothelial cell marker). Confocal microscopy combined with processing and analysis was utilized for the detection, location, and distribution of cell markers. Histomorphometric analysis revealed significant structural changes, including the medial area and neointimal area, between the injured and non-injured arteries at the 14-day timepoint. Moreover, the injured arteries showed an increase in percent area stenosis, compared to the non-injured control. Histological observation of fluorescently labeled images revealed α1B-AR is densely distributed in the neointimal and medial area of the injured carotid arteries compared to the non-injured control. NucBlue (nuclear) staining indicated an increase in cell number in the medial and neointimal areas of the injured artery. Together, these results offer insight into changes in vascular α1-ARs under low shear stress conditions suggesting that α1B-AR may be upregulated in response to injury and contribute to neointimal formation. NIH HL155288. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Low Hepatic Cardiolipin Levels Promote Increased Mitochondrial Electron Leak and Metabolic Dysfunction-associated Steatohepatitis
Authors: Lang Marisa , Shahtout Justin , Poss Annelise , Siripoksup Piyarat , Patil Mallikarjun , Peterlin Alek , Johnson Jordan 
Published: May 2024

Mitochondria adapt to changing energetic demands of the cell. We recently reported that mitochondrial membrane lipid composition represents a regulatory mechanism by which effciency of oxidative phosphorylation becomes altered. Metabolic-associated fatty liver disease (MAFLD) is a progressive disorder characterized by oxidative stress and accumulation of fat in hepatocytes that can lead to metabolic dysfunction-associated steatohepatitis (MASH). We hypothesized that MAFLD alters mitochondrial membrane lipids to induce mitochondrial electron transfer ineffciency and promotes oxidative stress. Lipid mass spectrometric analyses in four models of MAFLD (high-fat diet, ob/ob, carbon tetrachloride administration (CCI4), and Gubra-Amylin-NASH® diet), revealed that low mitochondrial cardiolipin (CL) is a common signature associated with all MAFLD models. In hepa1-6 cells, lentivirus-mediated knockdown of cardiolipin synthase (CLS, generates CL in mitochondria) was suffcient to reduce respiration and increase electron leak. Liver mitochondria from mice with a hepatocyte-specific knockout of CLS exhibited defects in mitochondrial bioenergetics including increased electron leak, concomitant to pathogenesis of MASH. Together, these findings provide evidence that a reduction in hepatic cardiolipin may drive the progression of MAFLD to induce MASH pathology. R01GM144613-03R01AG074535-02S2R01DK107397 07. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.