bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solubleform of (pro)renin receptor is excreted from mesothelial cells to peritoneal dialysis effluent of peritoneal dialysis patients (1173.5)
Authors: Oba Ikuko , Mori Takefumi , Takahashi Chika , Ohsaki Yusuke , Sato Emiko , Koizumi Kenji , Furusho Masahide , Chida Makiko , Naganuma Eri , Ito Sadayoshi 
Published: June 2021

Renin angiotensin system (RAS) is associated with peritoneal injury in peritoneal dialysis (PD). Angiotensin II dependent and independent role of (pro) renin receptor ((P)RR) to the cellular injury has been demonstrated. Thus, the present study determined the expression of (P)RR in drained PD effluent (PDE) and human peritoneal mesothelial cells (HPMCs) of the PD patients.PDE drained after 2.5% glucose PD solution during peritoneal equivalent test (0hours, 2hours, 4hours) was collected from PD patients. Human soluble from of (P)RR level was measured by ELISA. The expression of (P)RR on cultured HPMCs and media isolated from PDE were investigated by Western blot analysis and/or flow cytometry. HPMCs was specified by cytokeratin positive cells in flow cytometry. Full length or soluble (P)RR was identified by the molecular weight compared to the full length and soluble (P)RR synthesized in vitro from the expression vectors.Soluble (P)RR was detected in both plasma and PDE of PD patients. Time dependent increase in soluble (P)RR was observed in PDE. Expression of (P)RR was observed in cytokeratin positive mesothelial cells. Full length (P)RR was detected in HPMCs while soluble from of (P)RR was detected in concentrated cultured medium.These results indicate that full length (P)RR is expressed in HPMCs and excrete soluble (P)RR in drained PDE. The role of full length (P)RR in HPMCs and soluble (P)RR in plasma and PDE of PD patients requires further investigation.
Cardiomyocyte differentiation of mouse iPSCs regulated by polypeptide multilayer films (1180.21)
Authors: Fu Pei‐Wen , Wang Shih‐Ying , Chen Yu‐Ru , Lo Chun‐Min 
Published: June 2021

Polyelectrolyte multilayer film is an emerging method for substrate coating to modulate cellular behaviors. This material allows for modulation of thickness, stiffness, and adhesiveness. In this study, mouse induced pluripotent stem cells (iPSCs) were cultured on polypeptide multilayer films built up by the alternate deposition of cationic poly‐L‐lysine and anionic poly‐L‐glutamic acid, cross‐linked with EDC/sulfo‐NHS, and coated with gelatin. The characteristics of film thickness, roughness, and shear modulus were measured by AFM and QCM. Cardiomyocyte differentiation was evaluated by RT‐PCR analysis and immunostaining of cardiac markers, and cardiomyocyte beating was monitored by polypeptide multilayer‐coated electrodes using impedance sensing technique. The results showed that mouse iPSC colonies demonstrated better cell spreading and differentiation on even number layer of films, where the top layers are poly‐L‐glutamic acid films. In addition, the cardiomyocyte differentiation of mouse iPSCs showed a significant increase in the differentiation rate when higher concentration of EDC/sulfo‐NHS cross‐linkers was used to form the films. Our observations indicate a possible way to promote iPSCs toward cardiomyocyte differentiation on polypeptide multilayer films by changing the outermost polypeptide layer, the concentration of cross‐linkers, and the number of layers in the film.Grant Funding Source: Supported by the National Science Council in Taiwan
Pressure applied in vitro increases proliferation of renal proximal tubular cells (1180.7)
Authors: Diaz Bianca , Chen Jie , Gonzalez Juana , Poppas Dix , Felsen Diane 
Published: June 2021

Increased pressure in the kidney is a common finding in kidneys with obstructed ureters [UO]. In animal models of UO, increased cellular proliferation may contribute to renal damage and/or repair. We investigated the direct effect of pressure on proliferation of renal proximal tubular cells in vitro. Human HKC‐8 or rat NRK‐52E proximal tubule cells were grown at either ambient pressure, or at pressures of 60 or 90 mm Hg for 24 or 48 hr. Cells were grown in complete medium [CM; DMEM with 10% FBS] or in starvation media [SM; DMEM]. At 24 or 48 hr, cells were lysed and counted using the Cyquant assay. Western blot for proliferating cell nuclear antigen [PCNA] was determined, as were cell cycle measurements using flow cytometry. Blood gases were determined in an iSTAT system. HKC‐8 grown in CM for 48 hr at 60 mm Hg, demonstrated a 16.5 ± 5.8% increase in cell number compared to cells grown at ambient pressure. After 48 hr of 60 mm Hg pressure in SM, there was a 39.2 ± 5.1 % increase in cell number. HKC‐8 grown at 90 mm Hg in SM also demonstrated a significant increase in cell number. Similar results were found with NRK‐52E. Western blot confirmed increased expression of PCNA in pressurized cells. Cell cycle measurements demonstrated an increase in HKC‐8 in S phase, with a corresponding decrease in cells in G1. Pressure did not significantly affect pH, PCO2 or PO2 of either CM or SM. We previously showed [AJP Renal 297:F114, 2009] that pressure applied to HKC‐8 cells induces cytokine signaling. Here we demonstrate direct transduction of this mechanical stimulus into a proliferative response in HKC‐8 and NRK‐52E cells, measured by cell number, PCNA or increase in cells in S phase. Effects on proliferation were more pronounced in SM, suggesting that pressure may be able to [re‐]activate pathways normally turned off during starvation. Understanding the signaling pathways activated by pressure should lead to a better understanding of how pressure contributes to renal damage in UO, or in other diseases characterized by high pressure.Grant Funding Source: supported by CTSA, RUCCTS Grant#8 UL1 TR000043 Natl Ctr for Advancing Translational Sciences
Inhibition of cAMP stimulated VAMP2 trafficking in renal epithelial cells by small molecule inhibitors (1181.13)
Authors: Nahle Lana , Caceres Paulo , Ortiz Pablo 
Published: June 2021

cAMP stimulates exocytosis in many cell types in the kidney. In juxtaglomerular cells, cAMP stimulates renin exocytosis. In thick ascending limbs and collecting ducts, cAMP stimulates exocytic delivery of NKCC2 and aquaporin 2, respectively. The mechanism by which this occurs includes the vesicle associated membrane protein VAMP2. New compounds aimed at inhibiting VAMP2‐mediated exocytosis could be useful to target these renal processes. We hypothesized that delphinidin, a small molecule that binds VAMP2, and 4‐AD, an inhibitor of aquaporin 2 trafficking, block cAMP‐stimulated VAMP2 trafficking to the surface in renal epithelial cells. We expressed C‐terminus GFP tagged VAMP2 (GFP faces vesicle lumen or surface) in LLC‐PK1 cells. Confocal imaging showed that in polarized cells, VAMP2‐GFP localized to the apical surface, primarily in small clusters. We then measured cAMP‐stimulated surface VAMP2 delivery by surface biotinylation. We used forskolin/IBMX to maximally stimulate cAMP. In vehicle treated cells cAMP enhanced surface VAMP2‐GFP by 173±57% in 8 min (p<0.02). In cells pre‐treated with delphinidin chloride (50 µM) cAMP did not increase surface VAMP2‐GFP (baseline= 100, cAMP= 95±8%). Similarly, when cells were pretreated with 4‐AD (40 µM), cAMP failed to increase surface VAMP2‐GFP (baseline= 100, cAMP=108±14%). We concluded that cAMP stimulates VAMP2‐GFP trafficking to the surface in renal epithelial cells, most likely as part of the exocytic process. The small molecule delphinidin, and the V‐ATPase inhibitor 4‐AD block cAMP‐stimulated VAMP2 trafficking.Grant Funding Source: Supported by NIH, AHA
Ion channel modulation of chondrocyte cell volume regulation (1182.1)
Authors: Lewis Rebecca , Barrett‐Jolley Richard 
Published: June 2021

Healthy chondrocytes exist with depolarised resting membrane potentials (Vm); critical for volume regulation. Chondrocytes express several cell volume regulation channels, including Transient Receptor Potential (TRP) V4, V5 and V6 and epithelial sodium channels. We investigated mechanisms of cell volume regulation in healthy chondrocytes. Patch clamp electrophysiology was used to measure canine chondrocyte Vm (Vm=‐12±3mV; n=21). Hypotonic challenge caused a significant Vm hyperpolarisation of 11±1mV (n=9; p<0.05). We hypothesised this was due to Ca2+ influx activating a Ca2+‐activated potassium channel (KCa). Studies propose TRPV4 as a possible component of osmotically‐activated Ca2+ influx so we investigated this channel. However, the TRPV4 inhibitor, RN1734, failed to prevent hypotonicity‐induced hyperpolarisation (ΔVm=‐19±4mV, n=4; p<0.05). Application of a TRPV4 agonist, 4αPDD, caused no significant change in Vm (n=12), whole cell current (n=7) or cell volume (n=8). Furthermore, application of iberiotoxin or 2‐APB completely abolished the hypotonicity‐induced hyperpolarisation. This leads us to conclude that Ca2+ increase in response to hypotonicity is likely to result from an, as yet, unidentified range of ion channels and/or Ca2+ stores and the KCa channel responsible for the hyperpolarisation is a large‐KCa channel.Grant Funding Source: Supported by European Union Seventh Framework Programme(FP7/2007‐2013) under grant agreement 305815
Molecular pathways for water fluxes in mouse choroid plexus epithelial cells (1182.3)
Authors: Cha David , Crum Jeannine , Alvarez‐Leefmans Francisco 
Published: June 2021

Regulation and maintenance of cerebrospinal fluid (CSF) composition is crucial for brain function. Choroid plexus epithelial cells (CPECs) secrete most of the CSF and regulate its ion and water composition. However, the mechanisms of secretion and absorption of water across choroid plexus epithelium (CPE) are poorly understood. Secretion of CSF entails net water movement across CPECs from the basolateral membrane (blood‐facing) through the apical membrane (CSF‐facing). Water fluxes across cell membranes occur through aquaporin channels and cotransporters like the Na+‐K+‐2Cl‐ cotransporter 1 (NKCC1). Both NKCC1 and aquaporin‐1 (AQP1) are expressed in the CPECs apical membrane but are undetectable in the basolateral membrane. The inward water flux across the basolateral membrane of CPECs may be explained by the expression of other members of the gene families of AQPs and/or the cation‐coupled chloride cotransporters (slc12a). Using RT‐PCR, we detected transcripts for several AQPs in whole choroid plexus tissue. Transcripts for AQPs 1, 4, 7, but not 9, have so far been found. Immunolabeling studies in process will reveal the location of these proteins in the various components of the choroid plexus. Explaining the mechanisms of CSF production and absorption is key for understanding pathologies like hydrocephalous and increased intracranial pressure that cause brain ischemia and/or edema.Grant Funding Source: Supported by 226119 Seed Grant Proteomics Program 2012 Boonshoft School of Medicine
In‐cell cross‐linking and identification of the nuclear actor of activated T‐cells 5 protein interactome using the mass spectrometry‐cleavable covalent cross‐linker DC4 (1182.7)
Authors: Ramkissoon Kevin , DuMond Jenna , Izumi Yuichiro , Williams Chester , Gucek Marjan , Wang Guanghui , Burg Maurice , Ferraris Joan 
Published: June 2021

The Nuclear Factor of Activated T‐cells 5 (NFAT5) transcription factor undergoes hypertonicity‐induced nuclear localization and regulation of the transcription of osmoprotective genes. Its structure, function, compartmentalization, DNA‐, and protein‐protein interactions are influenced by the various cellular proteins that interact with it, including a number of kinases and phosphatases. Prior in vitro NFAT5 studies and ongoing in vitro peptide affinity chromatography indicate that NFAT5 is involved in a large number of protein‐protein interactions. To validate these in vitro results and to ascertain which interactions are physiologically relevant, we performed in‐cell protein crosslinking experiments. We used the collision induced dissociation (CID)‐cleavable cross linker DC4 in NFAT5‐transfected HEK 293 cells. Protein crosslinking was followed by column and/or gel purification of NFAT5 complexes, protease digestion, LC‐MS‐MS and protein identification analyses. The proteins identified by in‐cell analysis were cross‐referenced with the results of our in vitro experiments to help gain domain‐specific information on NFAT5 protein interactions.Grant Funding Source: Supported by the Intramural Research Program of the NIH, National Heart, Lung, and Blood Institute
Time dynamics of cerebral blood flow during LBNP (1183.11)
Authors: Kasprowicz Magdalena , Czosnyka Marek , Diehl rolf , Haubrich christina 
Published: June 2021

Background: The time constant (τ) estimates how fast the arterial part of cerebral vascular bed is filled with blood volume during the cardiac systole. We have demonstrated previously that τ provides new insights into time dynamics in different cardiovascular diseases and during CO2 challenge in normal subjects. In this study we aimed to investigate time dynamics of cerebral blood flow using τ during progressive lower body negative pressure (LBNP) test.Material and Methods:Simultaneous recordings of TCD cerebral blood flow velocity (CBFV) in MCA, Finapres arterial blood pressure (ABP) and heart rate (HR) along with end‐tidal CO2 (EtCO2) were performed in 38 healthy volunteers (26 ± 4 years) during LBNP test. τ and τ*HR [beat] were estimated during lower body negative pressure ‐ using mathematical transformation of ABP and CBFV pulse waveforms. The analysis of variance (ANOVA) with Bonferroni post‐hoc test were used to compare the differences in hemodynamic variables between the stages of LBNP test. The level of significance was set as 0.05.Key Results / Statistics: From baseline to maximal LBNP before the onset of presyncope the gradual shortening of τ by 74±6% (mean ±95%CI) of baseline was observed with no further decrease in τ at presyncope (76±8%) ‐ see figure 1. The τ*HR did not change significantly in the course of LBNP up to the presyncope when it increased by 119±11% of baseline (p<0.0013). At presyncope reduction in ABP was by 90±5% of baseline, in CBFV by 77±3% of baseline, and in EtCO2 by 81±5% of baseline whereas HR increased by 162±9% of baseline.Conclusion: The time constant Tau sheds light onto a new aspect of the pathophysiology of presyncope. Although the heart systole contributes an increasing part to the cerebral circulation the failure of cerebral circulation cannot be prevented. Tau*HR indicates a significant downslow of the cerebral circulation during LBNP just before the occurrence of presyncopal complaints.
Increases in sympathetic activity during cold pressor test does not cause cerebral vasoconstriction (1183.8)
Authors: Serrador Jorge , Blatt Melissa , Ghobreal Bemin , Falvo Michael 
Published: June 2021

The objective of this work was to determine whether increased sympathetic activity results in cerebral vasoconstriction. To assess the role of sympathetic activity, 10 healthy individuals participated in a cold pressor test in which they immersed their hand in ice cold water for 57.5±16.6 seconds. We continuously monitored beat‐by‐beat blood pressure, cerebral flow velocity in the middle (MCA) and anterior cerebral artery (ACA), common carotid artery (CCA) flow and end tidal CO2. As expected the cold pressor test produced a significant increase in sympathetic outflow causing mean arterial pressure to increase from 104±7 to 117±10 mmHg, P=0.005. In contrast CCA diameter did not change (6.7±0.2 to 6.7±0.2 mm), and flow increased slightly but non‐significantly (+6.0±6.2%). Similarly, we saw slight increases in flow velocity in the MCA (+3.0±6.7 %) and ACA (+7.5±4.9 %) but non‐significant. End tidal CO2 values did not change from baseline to end of cold pressor (40.3±1.1 vs 40.0±1.2 mmHg). In contrast, cerebrovascular resistance increased in the MCA (+9.7±5.7 %) and ACA (+11.5±5.0 %), likely due to the cerebral autoregulatory response to the increase mean arterial pressure. These data demonstrate that increased sympathetic activity was associated with a slight increase in common carotid, middle and anterior cerebral flow, all ~5%, indicating there was no cerebral vasoconstriction to reduce flow. The increase in cerebral flow was likely in response to increased neural activation due to pain and sensory inputs. Our finding that CCA flow increased the same amount as MCA and ACA supports the concept that sympathetic activity does not cause vasoconstriction at either the arteriolar or MCA level.Grant Funding Source: Supported by Dept of Veteran Affairs and NIH R21 DC009900
Maternal mortality dynamics in Kazakhstan (1185.1)
Authors: Kamalbekova G. , Magzumova R. 
Published: June 2021

In Kazakhstan, over the period since 2000‐2011, maternal mortality reduced per 100,000 live births, from 60.9 to 17.4 cases per year.Results: The analysis of indicators by regions in the Republic of Kazakhstan demonstrates the most favorable situation of reducing maternal mortality, what was observed in Mangistau region (from 160.5 to 24.7) in the Atyrau region (from 108.6 to 6.6) in Kostanai region (from 92.9 to 15.7) in the North‐Kazakhstan region (from 66.2) and in Astana (from 65 to 10.4). In the analysis of the absolute number of deaths during pregnancy, childbirth and postpartum periods on the pregnants on the period since 2008‐2011 in Kazakhstan, up to 12 weeks ‐ in average of 3.5 cases of death per year in the period 13‐21 weeks‐6.5 cases per year of 22 weeks or more‐6.5 cases per year, women in labor and puerperal‐77.5 cases per year.During the period since 2008‐2011 an average cause maternal mortality 40.7 for extragenital diseases, 18.5 cases‐obstetric hemorrhage, 13,7‐from preeclampsia 10.7‐from abortion, 4.7‐from uterine rupture, 3,5‐from sepsis, 075‐from an ectopic pregnancy.During the period since 2008‐2011 in South Kazakhstan region recorded 40 maternal deaths from extragenital diseases, 13 cases‐from obstetric hemorrhage, 9 cases‐from Gestoses, total‐82 cases.For recent 6 months in 2013 in Kazakhstan demonstrates decrease in the maternal mortality rate ‐ 15.1% compared to the same period in 2012.
The effect of increasing the protein content of breakfasts on satiety and cognitive function in undergraduate students (120.2)
Authors: Hutchison Christine , West Robert , Hollis James 
Published: June 2021

The effect of protein consumption at breakfast on appetite and cognitive performance was investigated using a randomized, cross‐over study design. Following an overnight fast, 33 healthy, college undergraduates (aged = 22±2 yrs, BMI = 23.5±1.7. kg/m2) were provided one of four breakfast treatments: no breakfast, CHO‐only, high‐CHO/low protein and low‐CHO/high protein. Baseline appetite questionnaires and plasma samples were collected and cognitive performance tests were administered at regular intervals for 240 minutes following breakfast. An ad libitum lunch meal was provided 240 minutes after breakfast, and the amount eaten recorded. Following the lunch meal, participants were allowed to leave the laboratory and food intake was recorded using a food log and hourly appetite questionnaires completed for the rest of the day. Eating breakfast reduced subjective appetite compared to eating no breakfast (p<0.05). While food intake at the lunch meal was lowest after the HP breakfast (p<0.05) total daily energy intake was lowest when participants consumed no breakfast (p<0.05). The macronutrient composition of the breakfast meal had no effect on subjective appetite or food intake (p>0.05). Analysis of plasma samples revealed a significantly lower glucose following the low CHO/high protein treatment as compared to the CHO only breakfast. (p<0.05). Plasma insulin concentration was lowest following the no breakfast condition (p<0.05) but did not differ following the different breakfast meals (p>0.05). Proactive interference in delay memory was sensitive to treatment (p = .056), the low CHO/high protein treatment reducing interference. Verbal fluency was sensitive to overall treatment (p < .05), and reflected a stronger effect of the low CHO/high protein breakfast over time. Verbal fluency was marginally sensitive to the treatment (p = .068), with the two protein treatments leading to continued improvement over time.Grant Funding Source: Supported by the National Pork Board
Tart cherries improve glucose tolerance and insulin signaling in obese Zucker rats (121.4)
Authors: Stull April , Kirakosyan Ara , Elks Carrie 
Published: June 2021

The objective of this study was to evaluate the therapeutic efficacy of tart cherries on insulin sensitivity (intraperitoneal insulin tolerance test; IPITT), glucose tolerance (intraperitoneal glucose tolerance test; IPGTT), and intracellular signaling (gastrocnemius skeletal muscle) in obese Zucker rats. The rats consumed either a control (n=11) or tart cherry (n=11; 4% cherry powder) diet for 8 wk. Their body weight, fat pad weight, food intake, and fasting glucose and insulin concentrations were not altered by tart cherries. The IPGTT and IPITT were conducted at the end of study and blood glucose concentrations were measured over a 2‐h period. During the IPGTT, the area under the curve for glucose was significantly lower in the cherry group when compared to the control group (16,630 ± 2,181 vs 21,025 ± 1,994 mg/dl•120min; p 蠄 0.05). However, there were no group differences in glucose concentrations during the IPITT. In the skeletal muscle, the serine phosphorylation of AKT was higher in the cherry group than control group. Also, there were no differences between the groups in the phosphorylation of AMP‐activated protein kinase (AMPK; insulin‐independent protein). These results suggest that tart cherry supplementation improves glucose tolerance and enhances the activation of the intracellular signaling protein AKT in obese Zucker rats.Grant Funding Source: Cherry Marketing Institute
Establishment and characterization of in vitro model of human beige adipocytes using adenoviral delivery of BMP7 (133.1)
Authors: Okla Meshail , Ha Jung‐Heun , Lee Meeae , Chung Soonkyu 
Published: June 2021

Browning of white adipose tissue is an attractive target to facilitate weight loss and improve metabolic health. Bone morphogenic protein 7 (BMP7) is known to stimulate brown adipogenesis, but the molecular identity and metabolic characteristics are unknown. To establish in vitro model of human beige adipocytes, human adipose stem cells (hASCs) were first infected with adenoviral (Ad)‐BMP7 followed by adipogenic differentiation. Delivery of Ad‐BMP7 to hASCs was associated with 1) positive correlation with PPARγ (r2=0.9), 2) a robust increase of UCP1, Cidea, ADR3, and DIO2, and 3) a significant increase of beige‐specific markers, including CD137 and TMEM26. The uptake of 2‐deoxy‐3H‐glucose and 14C‐oleic acid was significantly higher in adipocytes infected with Ad‐BMP7 compared to Ad‐GFP. Moreover, cAMP‐stimulated lipolysis was augmented in Ad‐BMP7 infected adipocytes compared to Ad‐GFP group. Taken together, we demonstrated that delivery of Ad‐BMP7 to hASCs induced beige adipocytes that expressed beige‐selective markers and resembled brown fat metabolic characteristics. Therefore, our human beige adipocyte model would serve as an important tool for the development of new strategies against obesity.Grant Funding Source: Supported in part by the NIH and NCRR