bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intestinal Barrier Protection by Probiotic Lactobacillus-Associated Indoles in Caco-2 and Enteroids
Authors: Bala Ajitha , Dadala Rhema , Antonio Jayson , Suntornsaratoon Panan , Ambat Jayanth , Li Wei Vivian , Gao Nan 
Published: May 2024

Gut bacteria generate from dietary tryptophan (trp) indole compounds, which act as potent signaling molecules intricately involved in the regulation of intestinal homeostasis and barrier integrity. Lactobacillus rhamnosus GG (LGG), a widely used probiotic, has demonstrated ability to restore the gut barrier in animal models of colitis and sepsis, as well as in children with irritable bowel syndrome. To investigate the hypothesis that LGG-derived indoles are responsible for its gut barrier-enhancing properties, we fed gnotobiotic mice trp-suffcient and trp-deficient diets. We then monocolonized them with LGG, using PBS gavaged mice as a control, and analyzed the ileal transcriptome by bulk RNA sequencing and both fecal and serum metabolomes by LC-MS. Using our novel bioinformatic tool METRCA, which correlates metabolites and gene networks, we uncovered an unexpected and substantial influence of indole spatial distribution on genes associated with gut integrity: some were significantly positively linked to tight junction (TJ) genes exclusively from the luminal side, some exclusively from the serum, and others from both. Specifically, we identified nine indoles—indole-acetamide (IAM), indole-carboxaldehyde (IAL), indole-3-lactic acid (ILA), indole-3-propionic acid (IPA), indole-3-acrylic acid (IAR), indole-3-carbinol (ICB), indole-acetic acid (IAA), indole-3-acetonitrile (IAN), and indole-3-carboxylic acid (ICA)—that demonstrated the potential to maintain gut barrier function. To assess their impact, we used a high-throughput system that measured permeability through transepithelial electrical resistance (TEER) and FITC-dextran (4 kDa) in polarized Caco-2 cells. By luminally challenging cells with Clostridium diffcile toxins (TOX), we induced barrier disruption to model leaky gut. Intriguingly, when applied luminally, IAA, IAN, ICA, and ILA rescued the TEER of Caco-2 cells exposed to TOX, while IAM, IAL, and ILA were effective when applied basolaterally, suggesting a strong polar component to their barrier repair capacity. FITC transport revealed a significant basolateral rescue effect of IAM and luminal rescue effect of IAA and ICA, indicating that different sets of indoles are required to repair the pore and leak pathways. Furthermore, we confirmed that basolateral IAM rescued FITC permeability and induced increased expression of TJ genes Tjp1 and Ocln in enteroids challenged with lipopolysaccharides. In summary, our research highlights the potential beneficial therapeutic application of certain indoles in repairing disrupted gut barriers. NIHR01-AT010243 (NG, RF), R01DK119198 (NG), NSF 1754783 (RF). 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.
Characterization of Ano1 expressing cells in the mouse corpus cavernosum
Authors: Hannigan Karen , Fox Emily , Cobine Caroline 
Published: May 2024

Background/objectives: Highly coordinated contraction and relaxation of smooth muscle cells (SMCs) is critical to penile function. The Ca2+-activated Cl− channel, Anoctamin-1 (Ano1) plays a role in this as antagonists of this channel inhibit contractile, electrical and intracellular Ca2+ activity. mRNA encoding Ano1 is highly expressed in whole rabbit corpus cavernosum (CC). Despite its significant contribution to erectile function, the specific cell type that expresses Ano1 has not been determined, with previous studies relying on morphological identification of cells alone. Atypical SMCs (ASMCs) expressing platelet derived growth factor receptor-a (PDGFRa; Pdgfra), myosin heavy chain ( Myh11) and Ano1 have been observed in the renal pelvis where they are thought to drive the activity in adjacent SMCs (Grainger et al. 2020; PMID: 32415739). Therefore, the objective of this study is to identify the cell type that expresses Ano1 in the CC. Methods: Cells were isolated from the CC of mice selectively expressing eGFP in PDGFRa+ cells (PDGFRa+-eGFP mice) and SMCs ( Myh11-eGFP mice). Cell suspensions were sorted using fluorescence activated cell sorting (FACS) and evaluated for expression of cell specific markers ( Pdgfra and Myh11) by qPCR. Enriched PDGFRa+ cells and SMCs were examined with ddPCR to determine the expression of Ano1. Protein expression was evaluated using immunofluorescent labeling of frozen CC sections with an antibody targeting Ano1. Results: FACS sorted Myh11-eGFP+ cells expressed Myh11 and Pdgfra. Sorting of PDGFRa-eGFP+ cells revealed two subpopulations, bright and dim. Examination of these two PDGFRa-eGFP+ subpopulations revealed that while both expressed similar levels of Pdgfra, the dim population also expressed Myh11 suggesting that these cells may be similar to ASMCs of the renal pelvis. ddPCR revealed that the PDGFRa-eGFP+ dim population had higher gene copy numbers of Ano1 compared to Myh11-eGFP+ cells. Immunofluorescent labeling of CC sections revealed that Ano1 protein was present in a subpopulation of PDGFRa+ cells. Conclusion: The data presented in this study demonstrates that Ano1 is expressed in mouse CC PDGFRa-eGFP+ dim populations that also express Pdgfra and Myh11; this is similar to ASMCs in the renal pelvis. Future directions include examining the relationship of PDGFRa-eGFP+ dim cells to SMCs and nerve terminals in the CC and to determine if these cells are also present in human CC. This cell population could represent a novel target for the treatment of erectile dysfunction in patients who do not respond to phosphodiesterase inhibitors. Funding: AUA Research Scholar Award to KIH, NIH DK129528 to CAC, NIH P20GM130459 for imaging and molecular cores. 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.
Assessment of Mitochondrial Function in a Mouse Model of Mild Chronic Kidney Disease Induced by High-Fat and High-Salt Diet
Authors: Paula Venisia , Decker Stephen , Stuart Deborah , Opurum Precious , Ramkumar Nirupama , Funai Katsuhiko 
Published: May 2024

Intro: Kidneys are known for high energy demands involved in active transport and are thus highly oxidative organs, consuming the second-highest amount of oxygen per gram of tissue at rest (only exceeded by the heart). Chronic kidney disease (CKD) is a complex disorder that presents substantial challenges in understanding its pathophysiological mechanisms, including mitochondrial alterations. However, there are no established mouse models that recapitulate the CKD phenotype observed in humans.Hypothesis: We hypothesized that a high-fat, high-salt diet would induce a mild CKD phenotype and mitochondrial dysfunction in mice. Methods: We subjected C57Bl/6 mice to a high-fat (42%) and high-salt (8% NaCl) diet (HF/HNaCl) or standard chow diet for 16 weeks (n=4 per group). Additionally, we conducted comprehensive investigations into mitochondrial function, focusing on state 3 mitochondrial oxygen consumption (Oroboros O2K) and adenosine triphosphate (ATP) production (Horiba Fluoromax). Differences between groups were determined using Student’s t-tests. Results: HF/HNaCl feeding resulted in polyurea indicated by an increase in 24-hour urine output (Chow: 1.5 ± 0.2 mL; HF/HNaCl: 3.7 ± 0.8 mL; p=0.05) and a 30% reduction in glomerular filtration rate compared to chow-fed animals (Chow: 911.2 ± 107.8 μL/min/100g; Hf/HNaCl: 639.5 ± 25.9 μL/min/100g; p=0.08), indicative of the development of mild kidney disease. Although subtle changes were observed in mitochondrial oxygen consumption and ATP production, the alterations were not statistically significant. Discussion: Our findings suggest that the induced mild CKD state via the dietary regimen led to moderate renal impairment without substantial impacts on mitochondrial respiratory capacity and ATP synthesis. The establishment of this mouse model provides a valuable platform for further investigations into the complex interplay between renal dysfunction and mitochondrial dynamics in the context of mild CKD, offering insights that may pave the way for the development of targeted therapeutic interventions for this prevalent and debilitating condition. This project was supported by grants from the National Institutes of Health. 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.
OxLDL/LOX-1 Mediated Sex, Age, and Cell Dependent Alterations in Mouse Thoracic Aortic Vascular Reactivity, Stiffness, and Remodeling
Authors: Wendt Trevor , Gonzales Rayna 
Published: May 2024

Elevated oxidized low-density lipoprotein (oxLDL) is a risk factor and component that worsens cardiovascular disease states. OxLDL can elicit its detrimental action, via lectin-like oxLDL receptor 1 (LOX-1) and has been shown to disrupt vascular function. In this study, we determined whether oxLDL, via LOX-1, alters aortic vascular reactivity and determined if sex differences exist. Thoracic aortic endothelium-intact or -denuded ring segments were isolated from intact C57BL/6J female and male mice and incubated with oxLDL ex vivo (50ug/dL; 2h). Using wire myography, cumulative concentration-response curves to phenylephrine (PE) were generated to determine contractile responses. From these curves, the EC50 was determined and used to contract rings to assess acetylcholine (ACh) dependent relaxation. Calculated aortic stiffness and remodeling, as well as mRNA expression of vasoactive and pro-inflammatory mediators were assessed. BI-0115 (10μM; selective LOX-1 inhibitor) was used to determine LOX-1 dependence. In this study, we investigated the effects of oxidized low-density lipoprotein (oxLDL) via the LOX-1 receptor on murine thoracic aortic vasoreactivity, stiffness, and remodeling across age and sex. Our results demonstrate a differential sex, age, endothelial cell, and LOX-1 dependent alterations to the effcacy of PE-induced contractile responses and ACh-mediated vasorelaxation in the thoracic aortic rings following oxLDL exposure. Additionally, we observed a distinct sex and age effect on thoracic aortic stiffness following exposure to oxLDL. There was also a sex effect on calculated vessel diameter, as well as an age effect on oxLDL-mediated inward remodeling that was LOX-1 dependent. We also observed an oxLDL and age dependent increase in LOX-1, IL-6, endothelin-1 (ET-1), and ET-1 receptor alpha and beta mRNA expression. Thus, LOX-1 inhibition and the resulting attenuation of oxLDL/endothelial-mediated alterations in aortic function suggests that there are differential sex differences in the role of oxLDL/LOX-1 in the thoracic aorta of male and female mice. In conclusion, acute exposure to oxLDL led to altered vasoreactivity, endothelial dysfunction, and changes in aortic stiffness and remodeling. These effects were in-part age, sex, endothelial, and LOX-1 dependent. This study reveals potential complex interactions in oxLDL/LOX-1-mediated vascular responses that could serve as potential therapeutic intervention for vascular diseases such as atherosclerosis. University of Arizona Valley Research Partnership Grant VRP37 P2 (RJG), American Heart Association 19AIREA34480018 (RJG), UA VRP Grant VRP55 P1a (TSW). 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.
Coronary Vascular Rarefaction in Heart Failure
Authors: Fopiano Katie Anne , Hardell Davis J , Patel Vijay S , Bagi Zsolt 
Published: May 2024

Coronary vasculature rarefaction has been thought to play a role in the development of heart failure (HF), causing reduced myocardial perfusion; understanding the role that coronary rarefaction plays within HF presents an avenue for therapeutic strategies. We assessed the coronary microvascular and small vessel networks in left atrial appendage (LAA) samples to determine differences based on HF status. LAA samples were obtained from 15 consecutive patients during cardiac surgery (BMI: 22.8-37.9, age: 51-82, M:F: 9:6, NonHF:HF: 11:4). LAA samples were paraffn-embedded or flash frozen whereby 40 μm thick sections were then immunolabelled using DyLight 594 fluorescent tomato-lectin dye and z-stack images were rendered using microscopy. Z-stack images were input into Vesselucida360 and the vessel networks were three-dimensionally reconstructed via unbiased automatic tracing with multiple quantitative endpoints calculated. LAA samples were also used for proteomic analysis via LC-MS followed by statistical and pathway analyses to determine differences in protein expression and pertinent pathways as well as in a wide-scale gene expression array (NanoString) to further study underlying molecular targets. We found that the number of branching nodes and total vessel length in the coronary vascular network was decreased in HF compared to NonHF patients. Whereas the total volume and surface area were similar between HF and NonHF patients. Proteomic analysis and principal component analysis identified differences in protein profiles in the two groups, with pathway analysis identifying cardiac contraction and metabolism, along with hydrogen peroxide catabolic pathways downregulated in HF. Gene expression profiling identified numerous hypoxia response and oxidative stress response markers as downregulated in HF LAA samples. The data obtained show coronary vascular rarefaction occurring in HF patients, implying potential implications in the progression of HF. Additionally, proteomic data point to the downregulation of hydrogen peroxide response pathways as a potential mechanism for coronary microvascular rarefaction that we want to elucidate in future studies. T32 HL155011 (KAF) F31 NS132564 (KAF). 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.
Role of CFTR in Polycystic Kidney Disease
Authors: Cebotaru Liudmila , Ciobanu Cristian 
Published: May 2024

Introduction: Polycystic kidney disease (PKD) causes numerous cysts to grow in the kidneys, liver and pancreas. These cysts are filled with fluid. In the United States about 600,000 people have PKD, which is the fourth leading cause of kidney failure. The two main types of PKD are autosomal dominant PKD (ADPKD), which is usually diagnosed in adulthood and autosomal recessive PKD (ARPKD), which can be diagnosed in the womb or shortly after a baby is born. ADPKD is associated with the slow but relentless formation of multiple renal cysts. CFTR is known to be involved in secreting fluid in ADPKD through its localization in the apical membrane. Thus, the plasma membrane is the expected site where CFTR functions. Here, we show that CFTR unexpectedly is located in primary cilia and plays a role in cilia length. ARPKD is associated with systemic and portal hypertension, fibrosis of the liver and kidney and enlarged kidneys, with fusiform dilation of the collecting ducts. Although it has been postulated that CFTR plays a role in fluid secretion in ADPKD, the opposite is true in ARPKD. For example, a double mutant of CFTR and polycystin/polyductin mice develop massively enlarged kidneys and die from renal failure at ~24 days after birth (Nakanishi et. al (2001). J. Am. Soc. Nephrol. 12, 719-725). Thus, knocking down CFTR makes the disease worse. Methods: We used for ADPKD a mouse model bearing the R3277C mutation in PC1 and ARPKD mouse model bearing pkhd1Pkhd1del3-4/del3-4 deletion. We injected male and female mice with 30 mg/kg of VX-809 every other day. Also, we injected ADPKD and ARPKD mice once with AAV1 del27-264CFTR at 30 days old and sacrificed at 90 days. Results: Cyst areas are significantly reduced in kidney and liver after treatment with VX809 or with AAV1 del27-264CFTR. Conclusion: These data indicate that VX-809 reduces proliferation and the presence of CFTR at the apical membrane while increasing CFTR at the basolateral membrane in kidney in ADPKD model and liver in ARPKD model. Demonstration of kidney and liver cyst reduction increases the therapeutic potential of VX-809 as a treatment of ADPKD and ARPKD. Also we are reporting direct evidence of involvement of CFTR in cyst reduction in liver and in kidney by using gene therapy method treating ADPKD and ARPKD mice with AAV1 del27-264CFTR which would bind to WTCFTR and correct the traffcking of CFTR in ADPKD and ARPKD mice. NIH and PKD Foundation. 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.
Identifying Cell Population Heterogeneity in Cerebral Palsy Muscle
Authors: Stewart Madison , Hu Lin-Ya , Kulkarni Vedant , Smith Lucas 
Published: May 2024

Cerebral Palsy (CP) is a neuromuscular condition that affects movement and muscle tone, and often leads to contractures. Muscle satellite cells (MuSCs) have been shown to decrease in CP, but the overall resident muscle cell populations have not been characterized. Our objective is to identify differences in the cell populations and transcriptomes of muscle biopsies taken from CP and typically developing patients (TD) using single cell RNA sequencing. We hypothesize that cells taken from CP patient muscle will have a different distribution amongst populations. Gene enrichment, psuedotime analysis, subclustering, and interactome analysis were conducted to investigate muscle resident cell populations. The results demonstrated that, while there was not a significant disparity between cell populations of CP and TD muscle, there were differences in the subpopulations of MuSCs and fibro-adipogenic progenitors (FAPs). These results indicate that FAPs from CP patients tend to be more pro-fibrotic and may signal to MuSCs to undergo apoptosis. This study may help to identify molecular and cellular targets for CP therapies. Funding provided by the Hartwell Foundation. 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.
How They Eat: An Examination of Digestive Physiology of Sympatric Prickleback Fishes
Authors: Steinmann Kaitlyn , Ye Tim , Saleh Sara , Herrera Michelle , German Donovan 
Published: May 2024

How fishes thrive on different diets is not understood as well as for terrestrial animals. Thus, examining the flexibility of gut function in fishes with different diets provides insight into dietary specialization in the largest vertebrate class. In this study, we measured the amylolytic activities in the guts of closely related, sympatric species: Xiphister mucosus (herbivore), X. atropurpureus (omnivore), Phytichthys chirus (omnivore), and Anoplacharus purpurescens (carnivore). For all species, the amylase activity decreased moving distally along the intestine, but less so for the carnivorous A. purpurescens. Overall, our results—more elevated amylase activity in those fish eating more algae—agree with the Adaptive Modulation Hypothesis (AMH), which suggests that there should be a match between enzymatic activity and dietary substrate intake. Measurements of proteases and lipases are in progress, but we anticipate some support for AMH in other enzyme classes. Moreover, we are also measuring these same enzyme activities in these same species fed omnivorous or carnivorous diets in the laboratory. The flexibility of the intestines of the fish species to accommodate different food types provides insight into their roles in the ecosystems and how fixed the vertebrate digestive system can be. NSF IOS 1355224 Undergraduate Research Opportunity Program at University of California, Irvine. 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.
A Comprehensive Approach to Graduate Education in the Biomedical Sciences
Authors: Dent Elena , Crider Emily A , Sullivan Jennifer 
Published: May 2024

There are roughly 130 biomedical sciences-related PhD training programs in the U.S. with about half of the graduates remaining in academia post-graduation. Biomedical sciences PhD programs emphasize rigorous training in research to prepare students to enter academia but may lack training in other areas that contribute to career success. Trainees face many challenges in graduate school, including meeting the basic scientific knowledge and research milestones, developing strong communication skills, and enriching their skillset through professional and career development opportunities to best position themselves for future success. To accomplish all of this while maintaining a healthy sense of self can be daunting. The Graduate School (TGS) at Augusta University (AU) aims to facilitate ground-breaking research alongside outstanding education by providing a holistic and comprehensive graduate experience. TGS is currently undergoing review and revision of three of the four arms of graduate education: academics, research, student well-being, and professional development. We use data collected from an external review and 52 currently enrolled and previously graduated (within 3 years) biomedical sciences PhD students to identify opportunities for improving the first-year core curriculum at AU. In response, TGS developed a first-year core curriculum committee tasked with reviewing, revising, and addressing gaps in the first-year core curriculum. Furthermore, TGS has developed and launched GradWell, a health and wellness initiative, and has also partnered with external collaborators to offer strategic professional development opportunities to biomedical sciences students, prioritizing holistic growth to enhance the student experience. Continuous programmatic evaluation related to curriculum, student well-being, and professional development is critical to ensure programs are meeting the evolving needs of students while incorporating innovative pedagogy to maximize training opportunities and the development of well-rounded research scientists. 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.