bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial targeting of the P-glycoprotein to reduce intestinal inflammation in ulcerative colitis
Authors: Sallis Benjamin , Foley Sage , Bucci Vanni , Ward Doyle , Houghton JeanMarie , McCormick Beth 
Published: May 2023

Ulcerative colitis (UC) is a devastating chronic disease characterized by aberrant colonic inflammation and intestinal dysbiosis. The pathognomonic ulceration as well as intestinal epithelial damage is driven by excess luminal infiltration and activation of neutrophils. Recently our group discovered a system of lipid mediators regulating transmigration of neutrophils from the colonic lamina propria across the epithelial barrier. During homeostasis the multidrug resistance efflux pump p-glycoprotien (P-gp) maintains a gradient of endocannabinoids, which limits neutrophil transmigration. During inflammation however, P-gp is downregulated and Multidrug resistance-associated protein 2 (MRP2), which secretes the neutrophil chemoattractant hepoxilin A3 is upregulated, promoting luminal infiltration of neutrophils. In ulcerative colitis P-gp is significantly downregulated, resulting in the excess luminal accumulation of neutrophils found in ulcer bases. We discovered that the balance of these multidrug resistant efflux pumps is dependent on the microbiome and its secreted metabolites, which is significantly altered in UC. Consequently, we are designing a consortium of bacteria to optimize the expression of P-gp on the host epithelium and thus restrain neutrophil transmigration in UC.Using antibiotic stratification experiments and fecal xenograft models we have identified specific bacterial species that increase P-gp expression, and thus likely restrain neutrophil transmigration. Thus far we have validated the role of 15 candidate bacteria and 78 bacterial metabolites in regulating P-gp expression and function either directly or through interactions with other bacterial species. Leveraging this understanding of microbial regulation of host efflux pumps as well as in-vivo population dynamics data we are developing an algorithm to predict the P-gp induction ability of all possible combinations of candidate microbe. Using this algorithm we will design P-gp high, mid, and low inducing consortia, to study the role of these populations on intestinal inflammation using murine models of ulcerative colitis. The development of such consortia has wide ranging implications for research and clinical practice alike from facilitating further study of the underlying inter-microbial networks regulating key host defense systems in the intestine to the development of a probiotic with the potential to limit colonic neutrophil infiltration in patients with UC. This work is supported by R01DK125407, T32AI132152, and F30DK134110 by National Institutes of Health. This is the full abstract presented at the American Physiology Summit 2023 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.
LRRC8A Anion Channel Associates with Myosin Phosphatase Rho Interacting Protein (MPRIP) to Regulate Vascular Function
Authors: Choi Hyehun , Nguyen Hong N , Lamb Fred 
Published: May 2023

Volume-regulated anion channels (VRACs) are activated by tumor necrosis factor alpha (TNFα) and angiotensin II. VRACs are composed of Leucine Rich Repeat Containing 8 (LRRC8) family proteins (LRRC8A, B, C, D and E) and LRRC8A is required for all VRACs. LRRC8A associates with NADPH oxidase 1 (Nox1) and modulates production of extracellular superoxide in vascular smooth muscle cells (VSMCs). We investigated vascular reactivity in mesenteric arteries from wild type (WT) and smooth muscle-specific LRRC8A knockout (KO) mice. KO vessels displayed enhanced responsiveness to multiple vasodilator agents; acetylcholine, sodium nitroprusside, PKA (forskolin) or PKG (BAY60-2770) activators and a Rho kinase inhibitor (Y-27632), compared to WT. This was associated with decreased RhoA activity and reduced ROCK-dependent MYPT1 phosphorylation at T853. To explore the mechanism of enhanced relaxation we immunoprecipitated LRRC8A-associated proteins from WT and KO VSMCs and analyzed these by mass spectroscopy. Myosin Phosphatase Rho-Interacting protein (MPRIP) was identified only in WT lysates. MPRIP is a scaffolding protein that binds to RhoA, MYPT1, and actin and regulates activity of the myosin light chain phosphatase complex. Association of LRRC8A and MPRIP was confirmed using IP/western blot, proximity ligation assay (PLA) and immunohistochemistry. LRRC8A binds to the second plextrin homology domain of MPRIP. Knockdown of MPRIP (siRNA) increased protein expression of LRRC8A in cultured VSMCs. To explore the relationship between Nox1/LRRC8A, superoxide and intracellular redox signaling events sulfenylation of MPRIP cysteine residues (-SOH) was quantified using DCP-Bio1 (a biotin-labeled dimedone derivative) pulldown with streptavidin beads and western blotting. Sulfenylation was significantly increased 3 min following TNFα stimulation (2.3 fold, n = 3, p < 0.05). It remains to be determined how this impacts association of MPRIP with its four binding partners. Disruption of interaction between Nox1/LRRC8A and MPRIP/RhoA/MYPT1/actin may underly enhanced vasodilation in VSMC-specific LRRC8A null blood vessels. This multi-protein complex provides a potential mechanism by which oxidants produced by Nox1 impact vasomotor function, linking inflammation to increased vascular reactivity and hypertension. NIGMS (5R35GM138191-02), NIDDK (1R01DK132948-01), NHLBI (1R01HL160975-01A1) This is the full abstract presented at the American Physiology Summit 2023 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 the Circadian Clock System in Trans-sulfuration Pathway and Tissue Remodeling
Authors: Tyagi Suresh , Tyagi Suresh , Sathnur Sathnur , Sen Utpal , Akinterinwa Oluwaseun , Zheng Yuting , Mokshagundam Sriprakash , Singh Mahavir 
Published: May 2023

Previous studies from our laboratory revealed that the gaseous molecule; hydrogen sulfide (H2S), a metabolic product of epigenetics which involves trans-sulfuration pathway for ensuring the metabolism and clearance of homocysteine (Hcy) from the body, helped mitigate the skeletal muscle’s pathological remodeling. Although the master circadian clock regulator that is known as the b rain and m uscle a ryl hydrocarbon receptor nuclear translocator l ike protein 1 (i.e., BMAL1) is intimately associated with S-adenosylhomocysteine hydrolase (SAHH) and Hcy metabolism but how trans-sulfuration pathway is influenced by the circadian clock system remains unexplored. We hypothesize that potential alterations in the functioning of circadian clock during sleep and wake cycle affect the skeletal muscle’s biology. To test this hypothesis, we measured serum matrix metalloproteinases (MMPs) activities using gelatin gels for analyzing the MMP-2 and MMP-9 activities. Further, employing the casein gels we also studied MMP-13 that is known to be influenced by the growth arrest and DNA damage-45 (GADD45) protein during sleep and wake cycle. The wild type (WT) and cystathionine β synthase deficient (CBS-/+) mice strains were treated with H2S and subjected for measurement of trans-sulfuration factors from their skeletal muscle tissues. The results suggested highly robust activation of MMPs activities in the wake mice versus sleep mice that appears somewhat akin to that of the “ 1-carbon metabolic dysregulation” which takes place during remodeling of extracellular matrix (ECM) in muscular dystrophy affected tissues. Interestingly, the levels of trans-sulphuration factors such as CBS, cystathionine γ lyase (CSE), methyl tetrahydrofolate reductase (MTHFR), phosphatidylethanolamine N-methyltransferase (PEMT), and Hcy-protein bound paraoxonase 1 (PON1) were attenuated in the CBS-/+ mice. However, treatment with H2S mitigated the attenuation occurring in the trans-sulfuration pathway. In addition, levels of mitochondrial peroxisome proliferator-activated receptor-gamma coactivator 1-α (PGC 1-α) and mitofusin-2 (MFN-2) were significantly improved by H2S intervention. Our findings suggest participation of the circadian clock system in trans-sulfuration pathway that affect the skeletal muscle remodeling and mitochondrial regeneration. HL-139047, DK116591 and AR-71789 This is the full abstract presented at the American Physiology Summit 2023 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.
KCC3a is regulated by HCO3- independently of pendrin
Authors: Ferdaus Mohammed , Wall Susan , Delpire Eric 
Published: May 2023

The inactive form of the Cl-/HCO3 exchanger - pendrin in humans results in Pendred syndrome. With dietary Na+ restriction, patients with Pendred syndrome experience significant metabolic alkalosis, hypokalemia, and lower blood pressure. K+ loss is often observed with metabolic alkalemia. K+ loss is also a significant danger for patients, especially those who are taking diuretics, have hypokalemia, or have electrolyte abnormalities. Recently, we discovered the K-Cl cotransporter-3 isoform-a (KCC3a) in intercalated cells that express pendrin. We demonstrated that loss of KCC3a decreased pendrin abundance and alkalemia increased KCC3a abundance. Our findings also suggest that Cl-, secreted by KCC3a, is recycled by pendrin, acting as a driving force for pendrin function. Based on our findings we hypothesized in this follow-up study that KCC3a is regulated by HCO3- independently of pendrin. To test our hypothesis, we examined the KCC3a abundance in pendrin knockout (KO) mice fed a Na+, K+ and Cl- deficient diet that caused K+ loss. We evaluated how the abundance of KCC3a in mice responded to HCO3- challenge with and without high salt diet. Losartan, an angiotensin II receptor type 1 antagonist, was administered to mice to explore the role of angiotensin II (Ang-II) in KCC3a-regulating signaling. To determine the role of HCO3- and aldosterone in KCC3a signaling, we also looked at how KCC3a levels changed to KCl, or K-citrate loading.On a Na+, K+, and Cl- deficient diet, KCC3a abundance was greater in pendrin-KO mice, indicating that this was the cause of the observed K+ loss. In a HCO3- challenge experiment, KCC3a abundance increased with HCO3- both with and without high salt and Losartan did not change KCC3a level, demonstrating an independent response from Ang-II. With K-citrate challenges but not with KCl loading, KCC3a abundance increased, indicating an aldosterone independent and HCO3- mediated response as citrate is metabolized to HCO3-. We also show the mouse cortical collecting duct M-1 cells express KCC3a and that expression is markedly enhanced in the presence of bicarbonate, but not alkaline pH. Taken together, our findings suggest that HCO3- is the primary signaling molecule responsible for increasing KCC3a abundance.Our results demonstrate that HCO3- is the key signaling molecule regulating KCC3a abundance and that, unlike pendrin, the response to increasing KCC3a abundance is not dependent on pendrin. NIH grants: R01DK093501 and R01DK110375, and by International Network of Excellence Leducq Foundation grant: 17CVD05. This is the full abstract presented at the American Physiology Summit 2023 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.
Effects of FOLFOX Chemotherapy Regimen and Exercise on Circulating Factors of Cardiovascular Disease in Mice
Authors: Baumfalk Dryden , Halle Jessica , Carson James , Smuder Ashley 
Published: May 2023

Background: Cancer patients treated with FOLFOX are burdened by an array of side effects which can lead to early cessation of treatment. Specifically, FOLFOX is associated with increases in arterial stiffness, LV-stunning/weakness, both of which can lead to acute or chronic risk of developing heart failure and cardiovascular disease. To increase cardiovascular fitness and prevent FOLFOX cardiotoxicity exercise interventions have been proposed; however, a dearth of information exists on the timing and type of exercise that should be performed. Therefore, the purpose of this study was to investigate FOLFOX-induced alterations in circulating markers associated with cardiovascular damage 4-weeks post cessation of treatment, and to determine whether exercise can be utilized to mitigate increases in risk associated markers of cardiovascular disease. Methods: Male C57BL/6J mice (3 months) received 4 cycles (1 injection every 2 weeks) of FOLFOX (5-fluorouracil 30mg/kg, oxaliplatin 6mg/kg, leucovorin 90mg/kg), and were randomized to subgroups of sedentary (FOX, n=12), exercise trained (EXFOX, n=10), or PBS shams (CON n=11, EXCON n=9). Exercise training consisted of 14 sessions of treadmill exercise (18m/min, 5%grade, 15 minutes) during weeks 2-4 of the recovery period. Following completion of the treatment/exercise training, mice were sacrificed after a 12h overnight fast and a minimum of 48h after the last bout of exercise. Circulating markers were evaluated using Luminex Magpix® multiplex analyzer (MILLIPLEX Mouse CVD1&CVD2 Bead Panel, Millipore Sigma, Burlington, MA, USA). Results: There was a significant effect of FOLFOX (p<0.05) for soluble endothelium selectin (sE-selectin), soluble platelet selectin (sP-selectin) and thrombomodulin. Significant effects of exercise (p<0.05) were found for soluble intercellular adhesion molecule-1 (sICAM-1), platelet endothelial cell adhesion molecule-1 (Pecam-1) and thrombomodulin. Conclusion: This preliminary investigation suggests there are systemic alterations in markers associated with cardiovascular disease following FOLFOX regimen occurring weeks after cessation of treatment. Low intensity exercise was unable to show any benefits in terms of preventing increases in these cardiovascular disease risk markers. These results promote further investigation into the impact these alterations may have on cardiac or vascular tissue following FOLFOX treatment. National Cancer Institue: R21-CA231131 & National Institutes of Health: R01HL14458 This is the full abstract presented at the American Physiology Summit 2023 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.
Using a Stepped Framework of Student-led Laboratories to Help Teach Science Communication in Physiology
Authors: Petzold Andy 
Published: May 2023

Instilling science communication skills within an undergraduate physiology education is paramount to success within the sciences. Failure to be successful in communicating science can lead to a variety of difficulties at both the professional level and while communicating effectively to a broader audience. Unfortunately, these misgivings that derive from science communication issues can have wide-sweeping, real-world consequences ranging from misrepresentation or misinterpretation of scientific findings, to misunderstanding regarding the scientific process to outright scientific misinformation. How to communicate science is an important skill that must be gained through a combination of practice and teaching. Introducing students to the basics of science communication within a single course through laboratory assignments can be used as a method of teaching varied communication methods. We have developed a framework, that has been used in several different physiology courses, to teach the basics of science communication alongside instruction surrounding the scientific method and basic laboratory techniques. Specifically, we have used a stepped approach to laboratory experiments that are driven by student interest and coupled this with three styles of science communication – a poster, a talk, and a paper. This stepped framework begins with a guided lab that allows students to test their own hypothesis with limitations and ends with a largely freeform, student-led experiment at the end of the semester. Students felt they were more engaged with the curricular material and had better learning outcomes compared to previous methods of instruction. This basic framework could provide a mechanism for instructing laboratory techniques, “real-world” science and science communication methods while keeping students engaged and excited about the coursework. This is the full abstract presented at the American Physiology Summit 2023 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.
PRDM16 Deficiency in Vascular Smooth Muscle Cells Aggravates Abdominal Aortic Aneurysm
Authors: Chang Lin , Wang Zhenguo , Mu Wenjuan , Zhao Guizhen , Guo Yanhong , Zhang Jifeng , Chen Eugene Y 
Published: May 2023

Abdominal aortic aneurysm (AAA) is usually asymptomatic until severe complications with high risk of lethality occur, predominantly involving aortic rupture. Currently, no drug-based treatments are available, primarily due to limited understanding of AAA pathogenesis. PR domain-containing protein 16 (PRDM16) is a transcriptional regulator that governs gene expression by cooperating with other transcription factors. It is highly expressed in the aorta, but its functions in the aortic tissue and AAA pathology are largely unknown. In this study, we investigated the roles of PRDM16 in vascular smooth muscle cells (VSMCs). By RNA-seq analysis, we found that VSMCs-specific Prdm16 knockout mice ( Prdm16 SMKO) already showed extensive changes in the expression of genes associated with extracellular matrix (ECM) remodeling and inflammation in the abdominal aorta under normal housing conditions without any pathological stimuli. We found that human AAA lesions displayed decreased PRDM16 expression in the aortic medial layer. Periadventitial elastase application to the suprarenal region of the abdominal aorta aggravated AAA formation in Prdm16 SMKO mice. During AAA development, VSMCs undergo apoptosis because of both intrinsic and environmental changes including inflammation and ECM remodeling. Prdm16 deficiency promoted inflammation and apoptosis in VSMCs. A disintegrin and metalloproteinase 12 (ADAM12) is a gelatinase which can degrade various ECM. We found that ADAM12 is a target of transcriptional repression by PRDM16. Adam12 knockdown reversed VSMC apoptosis induced by Prdm16 deficiency. Our study demonstrated that PRDM16 deficiency in VSMCs promoted ADAM12 expression and aggravates AAA formation, which may provide potential targets for AAA treatment. This work was partially supported by National Institutes of Health grants HL151524 (L. Chang) This is the full abstract presented at the American Physiology Summit 2023 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.
Improved workflow for analysis of smooth muscle calcium signals from intact arterial preparations
Authors: Boskind Madison , Nelapudi Nikitha , Williamson Grace , Juarez Rucha , Mendez Bobby , Zhang Lubo , Blood Arlin , Wilson Christopher , Wilson Sean 
Published: May 2023

Intracellular Ca2+ signals are well regarded for their regulation of cellular processes ranging from myocyte contraction, hormonal secretion, neural transmission, cellular metabolism, transcriptional regulation, and cell proliferation. Measurement of cellular Ca2+ is routinely performed using fluorescent microscopy techniques with biological indicators. Analysis of deterministic signals is relatively straightforward as relevant data can be discriminated based on the timing of cellular responses. However, analysis of stochastic events in complex tissues takes considerable time and effort that often includes visual analysis by trained investigators. The purpose of the current study was to determine if the image analysis workflow could be automated without introducing errors. This evaluation was addressed by re-analyzing a published “gold standard” dataset through visual analysis of Ca2+ signals from recordings made in pulmonary arterial myocytes of en face arterial preparations. We applied a combination of data-driven and statistical approaches with comparisons to our published data to assess the fidelity of the various approaches. Regions of interest with Ca2+ oscillations were detected automatically post-hoc using the LC Pro plug-in for ImageJ. Oscillatory signals were separated based on event durations between 4 and 40 seconds. These data were filtered based on cutoffs obtained from multiple methods and compared to the published manually curated “gold standard” dataset. After filtering, the number of true positives, false positives, and false negatives were calculated through comparisons to the gold standard dataset. Positive predictive value, sensitivity and false discovery rates were calculated. There were very few significant differences between the quality of the events and no systematic biases based on the data curation or filtering techniques. The lack of difference between manual data curation and statistically derived critical cutoff techniques leads us to question the importance of manually curating stochastic Ca2+ event datasets using labor-intensive visual observation techniques. NIH R01HL155295, R01HL149608 This is the full abstract presented at the American Physiology Summit 2023 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.