bluuebunny/crossref_metadata_2025_split huggingface dataset:
TRPV4 inhibition protects against hypokalemia during low K+ intake
Authors: Tomilin Viktor N. , Zaika Oleg , Mamenko Mykola , Pochynyuk Oleh M. 
Published: June 2021

Tight regulation of K+ balance is fundamental for normal physiology. Reduced dietary K+ intake, which is common in Western diets, often leads to hypokalemia and associated cardiovascular‐ and kidney related pathologies. Distal renal tubule and specifically the collecting duct (CD) is the only place of controlled K+ reabsorption via H+‐K+‐ATPase in the state of dietary K+ deficiency. We previously demonstrated that TRPV4 Ca2+ channel, abundantly expressed in the CD, is a potent kaliuretic factor essential for flow‐induced K+ secretion. Here, we investigated a potential role of TRPV4 in controlling H+‐K+‐ATPase‐dependent K+ reabsorption in the CD. Treatment with low K+ diet (<0.01% K+) for 7 days reduced plasma K+ levels in WT mice from 4.3±0.2 mM to 3.3±0.2 mM, but not in TRPV4 −/− mice (4.3±0.1 mM and 4.2±0.3 mM, respectively). Furthermore, we detected significant reduction in urinary K+ levels in balance studies upon switching to low K+ diet in the presence of TRPV4 inhibition. By using freshly isolated split‐opened CDs, we detected greatly accelerated H+‐K+‐ATPase‐dependent pHi extrusion in TRPV4 −/− mice when compared to WT mice. Finally, TRPV4 −/− animals had significantly more acidic urine (6.2±0.1 vs 6.7±0.2 in WT) on low K+ diet, which is consistent with increased H+‐K+ ATPase activity. In summary, we propose that TRPV4 inhibition could be a novel strategy to manage certain hypokalemic states in clinical setting.Support or Funding InformationThis research was supported by NIH‐NIDDK DK095029 (to O. P.), AHA 17GRNT33660488 (to O. P.), and ASN Ben J. Lipps Research Fellowship (to V. T.).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Response of intercalated cell BKα knock‐out mice to a high K diet
Authors: Ray Evan C. , Carrisoza‐Gaytan Rolando , Marciszyn Allison L. , Wu Peng , Liu Leah C. , Subramanya Arohan R. , Wang Wenhui , Flores Daniel , Kohan Donald E. , Kleyman Thomas R. , Satlin Lisa M. 
Published: June 2021

Flow‐induced K secretion (FIKS) in the cortical collecting duct (CCD) is mediated by apical Ca2+−/stretch‐activated BK channels. These channels also contribute to the renal adaptation to dietary K intake. BK channels are expressed in both intercalated (ICs) and principal cells (PCs) in CCDs. Several lines of evidence suggest that BK channels in ICs are responsible for FIKS: (i) the density of BK channels in ICs exceeds that in PCs and (ii) dietary K loading upregulates BKα expression predominantly in the apical membrane of ICs in rabbit CCDs. We generated a mouse with targeted deletion of BKα, the pore forming subunit of the BK channel, in ICs (IC‐BKα‐KO) by crossing floxed BKα mice with B1 V‐ATPase Cre mice, after confirming that the B1 Cre was expressed primarily in ICs in the kidney. As the targeted deletion in exon 7 of the BKα sequence was not expected to lead to a frame shift, immunodetectable BKα was identified in ICs of IC‐BKα‐KO CCDs using an antibody directed against the BKα C terminus. Perforated whole‐cell recordings performed at +60 mV in 7 CCD ICs in an IC‐BKα‐KO fed a HK diet revealed that 4 ICs had no BK currents and 3 ICs had low charybdotoxin‐sensitive K currents (37, 65, 90 pA) vs. readily detectable currents in 2 ICs in WT mice fed a control K diet (600–800 pA). IC‐BKα‐KO and floxed controls were fed a HK diet × 10 days to maximize BK channel expression and received isotonic saline IP to induce a high urine flow rate. Over 6 hr following volume expansion, rates of urinary Na (39.1±11.1 vs. 36.0±15.2 μmol/hr) and K (165.5±50.1 vs. 171.9±76.0 μmol/hr) excretion were similar in IC‐BKα‐KO (n=10) and floxed (n=17) mice of both sexes. KO mice exhibited a higher blood [K] (5.5±0.8 vs. 5.0±0.7 mM; p<0.05) and BUN (25.3±5.7 vs. 20.6±5.1 mg/dL; p<0.03) vs. floxed controls although BW did not differ (21.0±2.7 vs. 22.6±3.4. gm, respectively). The difference in blood [K] between male IC‐BKα‐KO and floxed mice was highly significant (5.7±0.7 vs. 5.0±0.7 mM; n=14 and 16, p<0.02). In the absence of volume expansion, rates of urinary Na (1.3±0.8 vs. 1.3±1.3 μmol/hr) and K (50.9±23.7 vs. 40.4±22.5 μmol/hr) excretion were similar in the two groups over a 6 hr period (n=9 and 15, respectively). These results suggest that in the absence of IC BKα, mice have a limited capacity for adaptation to a HK diet, as evidenced by the higher blood [K], but still demonstrate FIKS.Support or Funding InformationK08 DK110332, P30 DK079307, R01 DK038470, R01 DK098145, I01 BX002510This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sex Differences in Urinary Exosomes from Salt‐sensitive 129Sv Mice
Authors: Liu Lauren , Tuna Kubra , Chacko Kevin , Sanchez Victor , Schramm Whitney , Ahmed Hamzah , Alli Abdel 
Published: June 2021

129Sv mice are susceptible to the development of salt‐induced hypertension and renal damage. We and others observed that female 129Sv mice have lower systolic blood pressure compared to male 129Sv mice. We did not find differences in electrolyte excretion or osmolality between female and male 129Sv mice. Urinary exosomes originate from different cell types such as renal epithelial cells. Their cargo is a source of biomarkers in the pathogenesis of hypertension and renal disease. We recently showed kidney exosomes may play a role for intercellular communication in the nephron. We hypothesized that there are differences in the production of exosomes and their cargo from female and male salt‐sensitive 129Sv mice. Exosomes were characterized by size using NanoSight Analysis and by Western blotting for the exosomal markers flotillin‐1, annexin V, and Hsp70. Using nanoparticle tracking analysis, we found a greater concentration of urinary exosomes from salt‐loaded female 129Sv mice compared to age‐matched salt‐loaded male 129Sv mice. On a normal‐salt diet, the size of the urinary exosomes from the female mice was smaller compared to the male mice, but the opposite was noted when a high‐salt diet was maintained. Importantly, we found urinary exosomes from salt‐loaded female 129Sv mice are enriched in annexins compared to males. Future studies will be performed to determine if the enrichment of annexins in the kidney of female mice contributes to the up‐regulation of urinary exosomes and altered exosomal cargo.Support or Funding InformationThis research was supported by a National Institutes of Health grant K01 DK099617 (to A. A. Alli).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Astrocyte‐specific deletion of Kir4.1 increases normoxic ventilation after acclimatization to chronic sustained hypoxia.
Authors: Moya Esteban A. , Hawkins Virginia E. , Yip Gigi , Mulkey Daniel K. , Powell Frank L. 
Published: June 2021

Chronic sustained hypoxia (CH) produces ventilatory acclimatization to hypoxia (VAH), which involves time‐dependent increases of ventilation in normoxia and the hypoxic ventilatory response (HVR). Previous results show that glia are activated by CH and contribute to VAH but the contribution of astrocytes involved in central CO2‐sensitivity to VAH is not known. We tested the hypothesis that inwardly rectifying K+ 4.1 channels in astrocytes contribute to VAH using conditional gene deletion in transgenic mice. Conditional knockout (cKO) Kir4.1 mice had loxP sites at both ends of the entire Kir4.1 open reading frame and WT mice did not. WT and cKO Kir4.1 mice expressed tdTomato reporter and Cre‐recombinase/ERT2 receptors in astrocytes under the control of hGFAP promoter. Immunofluorescence against markers of astrocytes and Kir4.1 confirmed that tamoxifen treatment decreased Kir4.1 expression in astrocytes in CO2‐senstivie areas of the medulla of cKO Kir4.1 but not WT mice. After CH (PiO2 = 70 mmHg for 1 week), ventilation measured with barometric pressure plethysmography increased in normoxia, acute hypoxia and acute hypercapnia relative to chronically normoxic control mice. Ventilation was greater in normoxia after CH in Kir4.1cKO than in WT because of greater respiratory frequency and tidal volume. Ventilation in acute hypoxia or hypercapnia after CH was not significantly different between genotypes and metabolic rate was similar between genotypes at all O2 levels. The results support a role in astrocytes in the persistent hyperventilation in normoxia with VAH.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Assessing Sex‐Specific Effects of Ozone Exposure on Pulmonary Function and Lung Mechanics
Authors: Fuentes Nathalie , Nicoleau Marvin , Cabello Noe , Silveyra Patricia 
Published: June 2021

BackgroundExposure to ground‐level ozone, an oxidative pollutant, causes lung inflammation, which can lead to pulmonary injury and impair lung innate immunity. There is emerging evidence that pulmonary diseases such as asthma affect women disproportionally with a greater degree of severity than men. In addition, most hospitalizations for asthma in women occur during the luteal phase or around the peri‐menstrual stage. However, the combined effect of ozone and sex hormones in respiratory mechanics is unclear. Here, we hypothesized that circulating estrogen levels can regulate pulmonary function and lung mechanics following ozone exposure.MethodsWe performed gonadectomy and hormone replacement (17β‐estradiol, 2 weeks) in a group of adult male and female C57BL/6 mice. In control females, the stages of the estrous cycle were monitored by daily by vaginal smear, and confirmed by serum sex hormone levels. We exposed animals to 1 ppm of ozone or filtered air (FA) for 3 hours, and we compared lung function 24h after exposure with a methacholine challenge (MCh; 0 – 50 mg/ml) using the FlexiVent system.ResultsWe observed significant changes in respiratory parameters (Ers, H, Rrs, RN, G) in males and females, and in females exposed to ozone at different stages of the estrous cycle, at the two highest MCh concentrations. The pressure‐volume curves obtained demonstrated similar MCh concentration‐dependent changes. Gonadectomized males exposed to ozone had higher Rrs and Ers than females and males exposed to FA, and treatment with estradiol ameliorated these effects. Surprisingly, female mice in the metestrus and diestrus stages exposed to FA had higher Rrs and Ers values than when compared to the proestrus and estrus stages. Contrarily, exposure to ozone caused a decrease in parameters (Ers, Rrs) during metestrus and diestrus stages, but a slight increase of these in the proestrus and estrus stages.ConclusionsOur results indicate that pulmonary function following ozone exposure can be affected by circulating hormone levels. Future studies examining diseases associated with environmental pollutants should consider the women's menstrual cycle.Support or Funding InformationThe authors thank the Pennsylvania State University College of Medicine Genome Sciences Core Facility for Bioanalyzer analysis. The authors also thank Todd Umstead and Susan Di Angelo for assistance with training and experiments, and Dr. Joanna Floros for the ozone equipment. NIH Grant K01HL133520.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effect of Maternal Protein Restriction on the Surfactant System during Early Postnatal Life
Authors: Khazaee Reza , McCaig Lynda , Huang John , Hardy Daniel , Yamashita Cory , Veldhuizen Ruud 
Published: June 2021

IntroductionIntra‐uterine growth restriction (IUGR) is defined by a low birth weight and contributes to a variety of adult‐onset diseases with different severities between males and females. There is some evidence for structural and functional changes to the lung during the post‐natal period. However, the specific changes over time and the effects of IUGR on the pulmonary surfactant system are not fully elucidated. Pulmonary surfactant is critical for normal respiration, it is a lipid‐protein mixture which coats the inside of the lung and maintains the lungs' ability to expand easily during respiration. Therefore, in this study we investigated the effects of IUGR on the surfactant system and lung function during early postnatal life. It was hypothesized that IUGR leads to lung dysfunction through alterations of the pulmonary surfactant system.Materials and MethodsIUGR was induced in a pregnant rat model via a low protein diet. Briefly, pregnant rats were randomized to a control 20% or a low 8% protein diet. Rats at days 1, 7 and 21 were euthanized, and were either lavaged immediately (day 1) or were analyzed for lung compliance and elastance using a FlexiVent followed by lung lavage (day 7 and 21). Lavage was processed to obtain surfactant which was analyzed via phospholipid‐phosphorus measurements.ResultsWeights were significantly lower in IUGR offspring in all age groups compared to control offspring. Surfactant analysis demonstrated a significant decrease in the amount of phospholipid surfactant of IUGR female offspring compared to control female offspring at day 1 (p<0.01). Also, the surfactant phospholipid content at birth (day 1) for both control and IUGR males and females was significantly higher compared to animals at day 7 and 21 (p<0.01). The results showed that lung compliance in 21‐day female IUGRs (but not male IUGRs) was significantly lower compared to female controls (p<0.01), while elastance was significantly higher for this group compare to female controls (p<0.01). Day 7 male and female offspring showed no difference for compliance and elastance compare to the control groups.Discussion and ConclusionIUGR resulted in alterations in surfactant content at day 1 and lung compliance at day 21 in IUGR females compared to control females. This shows that IUGR alters the lung function, and the effect was different between males and females. No changes in the extracellular surfactant content in 21‐day female IUGRs suggests that the lower lung compliance is potentially the result of alterations happened to surfactant biophysical properties under IUGR. These potential alterations will be investigated by assessing the reducing surface tension ability of the surfactant.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differential Ubiquitination of Profilin‐1 in Hypoxia‐Induced Pulmonary Hypertension
Authors: Zhao Jingru , Wade Brandy , Ma Jing , Hart Charles Michael , Sutliff Roy 
Published: June 2021

Pulmonary hypertension (PH) is a chronic illness characterized by increased pressure in the pulmonary arteries due to the thickening and constriction of the arterial walls. Vascular thickening is in part due to proliferation of smooth muscle cells. The ubiquitin proteasome system is an important regulator of cellular proliferation that alters protein stability and expression by modifying lysines (K) within target proteins with ubiquitin moieties. Addition of ubiquitin can alter activity of a protein or mark them for degradation. We hypothesized that hypoxia‐induced changes in ubiquitination impact PH development. Mass spectrometry (MS) was used to screen changes in ubiquitination of proteins in lung tissue from mice exposed to chronic hypoxia (10% O2) for 3 weeks. Profilin‐1, a mediator of actin‐polymerization, had decreased ubiquitination on K54 (Fold change −1.86) and K126 (Fold change −1.40). Profilin‐1 is known to play a role in cellular proliferation and its overexpression leads to increased wall thickness in aortas of spontaneously hypertensive rats. However, its role in PH is not well characterized. Proflin‐1 promotes actin polymerization by binding directly to ADP‐actin and catalyzing nucleotide exchange. Actin polymerization plays a key role in cellular proliferation, cell motility, and muscle contraction. We observed no difference in profilin‐1 protein levels in hypoxia‐exposed human pulmonary artery smooth muscle cells (HPASMC) and lungs from chronically hypoxia‐exposed mice when compared to normoxic controls (P>0.05). This lack of an effect of ubiquitination on protein levels suggests that Profilin‐1 ubiquitination could regulate its activity rather than stability. Preliminary fractionate on results show increased association of Profilin‐1 and G‐actin in hypoxia. Furthermore, disrupting actin polymerization using actin polymerization inhibitors decreased HPASMC proliferation. Therefore, our results indicate that reduced levels of ubiquitinated Profilin‐1 may promote actin polymerization which increases proliferation and contributes to PH. In addition, they suggest that changes in protein ubiquitination may contribute to PH progression.Support or Funding InformationThis work was supported in part by Merit Review funding from the Department of Veterans Affairs, Office of Research and Development (1I01BX001910 to CMH), by NIH Grant R01HL102167 (to CMH and RLS), and by support from NIH T32 HL076118 and American Heart Association 16POST30930007 (to BEW). MS work was performed by the Emory Integrated Proteomics Core.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Fast, transient relaxation of rat pulmonary artery by angiotensin II via AT1R‐eNOS signaling pathways
Authors: Kim Hae Jin 
Published: June 2021

Angiotensin II (AngII) is conventionally known as a vasoconstrictive agonist in the large conduit arteries. However, our preliminary study showed that the application of AngII induces only a transient, weak contraction in pulmonary arteries (PAs) followed by persistent desensitization. We have previously reported eNOS expression in pulmonary smooth muscle cells (PASMCs). Here we hypothesized that the concomitant activation of the myogenic eNOS by AngII might limit the contractile responses of PA. Myograph study (isometric contraction of vessel rings) of the rat PAs showed biphasic dose‐response to AngII with peak response at 1 μM. When pre‐treated with L‐NAME (NOS inhibitor) or ODQ (guanylate cyclase inhibitor), the transient AngII‐contraction became augmented and sustained. The AngII‐contraction was abolished by losartan (AT1 receptor antagonist), while neither PD123319 (AT2 receptor antagonist) nor A779 (Mas receptor antagonist) affected the AngII‐contraction. In human PASMCs, eNOS expression was confirmed, and the pro‐activating phosphorylation of Ser 473 in Akt and Ser 1177 in eNOS by AngII treatment was consistently observed by immunoblot. Also, the membrane expression of AT1R was sensitively shifted to the cytosol by AngII. Consistent with the AT1R internalization, the second AngII hardly induced any contractile response in PAs. Interestingly, the desensitization was also significantly removed by the treatment of L‐NAME, immediately after the washout of first AngII application, suggesting the involvement of eNOS signaling pathway in the control of AT1R recycling. Taken together, we proposed that the auto‐inhibitory role of the muscular eNOS in PAs play physiological roles of active relaxation under various vasoconstrictive conditions, preventing excessive contractile response of the low‐pressure pulmonary circulation.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Building a Pedigree: Utilization of Patient Encounters to Strengthen Genetics Foundation
Authors: Morrow Kyle Adam , Carter Ronda F. 
Published: June 2021

Integration of basic science knowledge with clinical reasoning skills fosters long‐term retention of material. Evidence shows that active learning increases student performance outcomes in nearly every metric studied. However, resources aimed at teaching educators how to actively engage their students, especially within the medical school curriculum are largely absent. Here, we describe a team‐based learning (TBL) strategy intended to hone both patient interviewing skills and the ability to incorporate patient history and presentation into the construction of a genetic pedigree. In addition to other required courses, our first‐year medical students are enrolled in molecular medicine and primary clinical skills (PCS) courses. One week prior to the TBL event, students learned how to take a patient history and summarize key clinical factors in the PCS course. In the molecular medicine course, students learned basic inheritance patterns (dominant, recessive, mitochondrial, and sex‐linked) and completed a case‐based independent assignment designed to enhance their ability to construct patient pedigrees. Within the TBL event, students interviewed standardized patients with suspected genetic disorders in their family in real time, obtaining a thorough family history as indicated by the patient's clinical presentation. After the interview, students worked within their individual teams to construct a likely patient pedigree. Inheritance pattern, recurrence risks, and proper patient counseling were discussed as a class after evaluating one team's representative pedigree. Three days after the TBL event, students were given their normal molecular medicine exam. In addition to a >10% increase in exam performance on the genetics topics over the previous year where this strategy was absent, the students communicated an increased understanding of how to properly take a patient history and an enhanced awareness of potential genetic influences on the larger clinical picture.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Multi‐facet Application of High Impact Practice‐Personal, School, and Community
Authors: Chakraborty Tandra R. 
Published: June 2021

High Impact Practices (HIP) are now a nationally recognized form of instruction that enhances student's engagement, active, cooperative and collaborative learning which makes the learning experience of students fun and memorable. In a Neurobiology course offered to the junior and senior college level students (Biology and Neuroscience majors) some of the active learning strategies that I find most beneficial are, implementation of technology using iPads, application formal debate, role‐playing (dramatic presentation, using technology), group work, clarification pauses, and documentary movies related to the topic of interest, peer survey's and Neuroscience fair. Although all of the mentioned teaching strategies have their own benefits some can have an even broader impact at the personal, school and community level. The ‘Neuroscience Fair’ was one of the most effective and well appreciated by both scholars and students. Students work in groups on assigned projects and research on various complex concepts of Neuroscience e.g. mechanism of Alzheimer's disease and then design a model to explain the project in layman's terms in such a way that middle schoolers can understand the concept. Survey questionnaires are made for middle school students, presenters, and judges. Our survey results indicate a positive correlation between student liking and understanding the concepts of the presentation. 100% of the faculty judges thought the concepts were brilliant and creative. Student presenters found it to be hard work but were extremely positive with their performance and acquired knowledge. The Neuroscience Fair is an attempt to create a personal‐school‐community partnership to enhance community awareness of neurodegenerative diseases and concepts by peer‐assisted learning.Support or Funding InformationAdelphi UniversityThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.