bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Hypertension Induced by Clozapine is Related with Increased Renal Sodium Transporters in Mice
Authors: Ren Zhiyun , Wang Weiwan , Zhang Chenyang , Ye Min , Wang Xiaoyan 
Published: May 2022

IntroductionHypertension is caused by multi‐factors, and the pathogenesis is linked to, generally, the increases in the protein expressions and functions of renal sodium transport proteins along the nephron. One of the major side effects of clozapine (common antipsychotic drug) is hypertension. The mechanism is unknown.Hypothesisthe pathogenesis of the clozapine‐induced hypertension is associated with increases of renal sodium transport proteins.Methodswe examined the blood pressures (BP) and protein expressions of major sodium transport proteins profiled along the renal tubules in the C57Bl6/J male mice (9 weeks old, n=4‐5/group) treated with clozapine at three doses of 5,10 and 20 mg/ kg for 1 week via intraperitoneal injection.Resultblood pressures (tail‐cuff, BP98A, softron, Japan) were higher in clozapine at 20mg/kg/day than vehicle (SBP: 130±1.64 vs 109±1.39, DBP: 87 ±4.12 vs 69±2.10 mmHg, n=5/group) and not altered at 5 & 10 mg/kg/day. There were no differences in BW, serum/urine creatinine and electrolytes except for a slight increase in serum sodium at dose of 20 mg/kg (152.8±0.71 vs 150.6±0.40, mmol/L). In renal homogenates, total protein abundance of NaPi2 (western blotting,199±26% of vehicle) NKCC2(184±20), NCC(213±14),and ENaC‐α(217±47),were higher at 20 mg/kg than vehicle. No increases were found in protein expressions of NHE3, αNKA, ENaC‐β and ENaC‐γ. The expressions of renin, AT1R and ACE at 20mg/kg were similar between groups while ACE2 was decreased (42±10). No increases were found in protein expressions of pNKCC2 in 5&10mg/kg(100±50,45±15); NCC was increased at 5 mg/kg (175±9); α NKA was increased in 5mg/kg (216±5) and 10mg/kg (163±2) groups.In plasma membrane enriched fraction (17k), NKCC2(204±43) and ENaC‐α(381±28)were higher at 20 mg/kg than vehicle. In intracellular membrane enriched fraction (200k), NKCC2(521±127) was higher than vehicle. Phosphorylated NKCC2 was increased in renal homogenates(331±35),17k(427±87) 200k(521±127) but WNK4 was not changed.Additional mice were treated with clozapine at 20mg/kg/day via osmotic mini‐pump for 1 week (mini‐pump) or administrated by intraperitoneal injection for 2 weeks (2wks). Increases of renal NKCC2 (mini‐pump:180±21, 2wks:153±18) and NCC (mini‐pump:171±22, 2 wks:160±23) were also found in those models.Conclusionsincreases of renal sodium transport proteins, mainly pNKCC2 and NKCC2, contribute to the dose‐related increase of BP in mice treated with clozapine and may play an important role in the pathogenesis of the clozapine‐induced hypertension.
Erythrocyte Fatty Acids and Association with Cardiometabolic Risk Factors in Free‐Living Elderly
Authors: Jehi Tony , Sabate Joan , Bitok Edward , Rajaram Sujatha 
Published: May 2022

Aging significantly increases the incidence of various cardiometabolic disease risk factors including diabetes, insulin resistance, hypertension, obesity, and dyslipidemia. These factors, in return, exacerbate the risk of cardiovascular disease (CVD), the major cause of morbidity and mortality among the elderly in the U.S. Unsaturated fats, specifically n‐3 polyunsaturated fatty acids (n‐3 PUFAs), have been shown to be inversely related to CVD risk factors, while saturated fat seems to increase the risk for CVD. Not much is known on the association between different fatty acids and cardiometabolic factors, especially in the elderly population.In a subset of the Walnuts and Healthy Aging (WAHA) study, a dual center, randomized controlled trial, we wanted to assess the possible associations between various red blood cell (RBC) membrane fatty acids, biomarkers for long‐term intake of fatty acids, and select cardiometabolic risk factors. Our study encompassed 192 participants with a mean age of 69 years from the Loma Linda, CA center only. The RBC membrane fatty acids and cardiometabolic risk factors (blood pressure, blood lipids, and fasting glucose) were measured at baseline and at the end of one year.RBC membrane n‐3 PUFAs were inversely associated with total plasma cholesterol (ß = ‐3.83; p= 0.02), triglycerides (ß = ‐7.66; p= <0.01), and fasting glucose (ß = ‐0.19; p=0.03). N‐6 PUFAs were positively associated with systolic blood pressure (ß=1.10; P=0.02). Mono‐unsaturated fatty acids were positively associated with TAG (ß = 4.16; P=0.03). Total saturated fatty acids were not associated with any of the cardiometabolic risk factors.RBC membrane fatty acids are good long‐term markers of dietary intake of fatty acids and can be used for diet‐disease relationship studies. Among elderly participants, increased n‐3 PUFAs in RBC may be predictive of lowered cardiometabolic risk.
Manipulation of Left Ventricular Loading Conditions is Necessary to Identify Diastolic Dysfunction in Swine with Repetitive Pressure Overload‐Induced HFpEF
Authors: Gilligan Alexandra K. , Nsumbu Dorcas , Tajlil Arezou , Canty John M. , Weil Brian R. 
Published: May 2022

ObjectiveDiagnosis of heart failure with preserved ejection fraction (HFpEF) is often complicated by the fact that many patients exhibit normal left ventricular (LV) mechanics at rest with a reduction in diastolic compliance that is only revealed when loading conditions are altered (e.g., during exercise stress). In an effort to identify parameters of diastolic function that could be utilized to detect alterations in compliance without manipulation of LV loading conditions, we utilized invasive hemodynamic analysis and speckle‐tracking echocardiography (STE) to assess diastolic strain and stiffness in swine with repetitive pressure overload (RPO)‐induced HFpEF.MethodsSwine (n=13) were subjected to 2‐weeks of RPO via daily intravenous administration of phenylephrine (PE; 400 ug/min; 1 hour/day) through an indwelling jugular vein catheter. Indices of LV relaxation as well as LV minimum and end‐diastolic pressure were obtained invasively before and after RPO at rest and during transient PE‐induced alterations in loading conditions. STE (Vivid 9; GE) was also performed throughout a single cardiac cycle to collect circumferential diastolic strain data, which were used alongside echocardiography‐derived measurements of chamber radius and wall thickness as well as catheter‐derived measurements of LV pressure to calculate regional and global circumferential subendocardial diastolic stiffness before and after RPO.ResultsCompared with baseline measurements, 2‐weeks of RPO did not significantly increase the time constant of LV relaxation (Tau; Figure A) or decrease the rate of LV pressure change during isovolumic relaxation (dP/dtmin; Figure B). Circumferential subendocardial stiffness derived via STE across a single cardiac cycle at rest was also unaffected by RPO (Figure C), despite a significant reduction in diastolic compliance that was revealed by construction of two‐point end‐diastolic pressure‐volume curves (Figure D) after manipulation of loading conditions (Figure E). Interestingly, single‐cycle STE‐derived stiffness measurements made during acute pressure overload were also similar at baseline and after RPO due to persistent elevations in LV minimum diastolic pressure during PE infusion at both timepoints.ConclusionsAlthough reductions in LV diastolic compliance are evident after chronic RPO when loading conditions are manipulated, abnormalities in LV mechanics are not exhibited at rest even when STE is used to assess diastolic stiffness throughout a single cardiac cycle. These findings highlight the challenges associated with identification of myocardial stiffening at rest in patients with HFpEF and reinforce the importance of studying LV mechanics under variable loading conditions.
Additive Effects of Diabetes and Lower‐Limb Amputation on Osteoarthritis with Comparison to Diabetic and Healthy Controls
Authors: Ngo Wayne , Finnerty Caitlyn , Finco MG , Holley Bethany , Menegaz Rachel A. 
Published: May 2022

Individuals with type II diabetes and individuals with lower‐limb amputation each have increased risks of developing osteoarthritis compared to the general population. Despite the high co‐occurrence of type II diabetes with lower‐limb amputations, the additive effects of these conditions are unclear. In order to better manage the risk of developing osteoarthritis in these populations, a better understanding of how diabetes and amputation might compound osteoarthritis risk is needed.We measured hip and knee joint space, as indicators of osteoarthritis, in four groups of individuals: 1) lower‐limb amputees with diabetes, 2) lower‐limb amputees without diabetes 3) diabetic controls, and 4) healthy controls. We hypothesized lower‐limb amputees with diabetes would have the most impaired musculoskeletal health, followed by amputees without diabetes, diabetic controls, then healthy controls.30 total CT scans of males (42‐79 years; BMI 19.7 ‐ 48.9 kg/m2) were obtained from the New Mexico Decedent Image Database. 10 scans were identified for amputees, diabetic controls, and healthy controls. Half of the lower‐limb amputees had diabetes while half did not, to differentiate effects of diabetes and amputation on musculoskeletal health. 3D Slicer software was used to measure hip and knee joint spaces as indicators of osteoarthritis. Comparisons between groups were assessed using Kruskal‐Wallis with Dunn’s post hoc tests.Amputees with and without diabetes showed significantly narrower hip (p=0.01) and knee (p=0.08) joint space bilaterally compared to diabetic and healthy controls. This result suggests amputees could be at a higher risk of developing lower‐limb osteoarthritis compared to diabetic and healthy individuals, which is in line with prior work demonstrating the prevalence of osteoarthritis in the amputee population.In agreement with our hypothesis, box plots showed trends of amputees with diabetes having the most narrowed joint space, followed by amputees without diabetes, then diabetic controls, and healthy controls. While not statistically significant, these trends suggest amputees with diabetes are at increased risk of developing osteoarthritis compared to amputees without diabetes. Perhaps the aggressive management of blood glucose and post‐amputation physiotherapy treatments could help reduce joint deterioration in these patients. Future work will focus on increasing sample size to assess if these findings are generalizable to a larger population.Increased risks of osteoarthritis can lead to pain, limited mobility, and decreased quality of life. This study can potentially inform clinical standards of care for patients with amputations. Earlier interventions such as proactive musculoskeletal screenings and targeted exercises may reduce risks of developing osteoarthritis, leading to improved clinical outcomes.
Loss of Endothelial CFTR Drives Barrier Failure and Edema Formation in Lung Infection and Can Be Targeted by CFTR Potentiation
Authors: Erfinanda Lasti , Zou Lin , Gutbier Birgitt , Lei Disi , Reppe Katrin , Teixeira Alves Luiz Gustavo , Kneller Laura , Schneider Bill , Michalick Laura , Fatykhova Diana , Schneider Paul , Liedtke Wolfgang , Sohara Eisei , Mitchell Timothy J. , Hocke Andreas , Hippenstiel Stefan , Mall Marcus A. , Witzenrath Martin , Kuebler Wolfgang M. 
Published: May 2022

Pneumonia is the most common cause of the acute respiratory distress syndrome (ARDS), a potentially fatal lung disease characterized by hyperinflammation and endothelial barrier failure. Infectious and inflammatory stimuli can cause rapid downregulation of cystic fibrosis transmembrane conductance regulator (CFTR), and inhibition of CFTR has been proposed to increase lung microvascular endothelial permeability in vitro. Here, we identify loss of lung microvascular endothelial CFTR as important pathomechanism in lung barrier failure in pneumonia‐induced ARDS, delineate the molecular signaling pathway underlying this effect and identify CFTR potentiation as novel therapeutic strategy in ARDS.CFTR was downregulated in endothelial cells following Streptococcus pneumoniae(S.pn.) infection in human and murine lung tissue. Isolated perfused lungs revealed that CFTR inhibition increased endothelial permeability in parallel with intracellular Cl‐ and Ca2+concentrations ([Cl‐]i, [Ca2+]i). Inhibition of the Cl‐ sensitive with‐no‐lysine kinase 1 (WNK1) replicated the effect of CFTR inhibition on endothelial permeability and endothelial [Ca2+]i while WNK1 activation attenuated it. Endothelial [Ca2+]i transients and permeability in response to inhibition of either CFTR or WNK1 were prevented by inhibition of the cation channel transient receptor potential vanilloid 4 (TRPV4). Mice deficient in Trpv4 (Trpv4‐/‐) developed less lung edema and protein leak than their wild‐type littermates following infection with S. pn. Conversely, lungs of heterozygous Wnk1‐deficient mice (Wnk1+/‑) showed spontaneous leak. The CFTR potentiator ivacaftor prevented CFTR loss and reduced endothelial leak in response to pneumolysin (PLY), a key S.pn. virulence factor, or plasma from COVID‐19 patients in vitro, and prevented lung edema and protein leak after S. pn.infection in vivo.Lung infection causes rapid loss of CFTR that promotes lung edema formation through intracellular Cl‐accumulation, inhibition of WNK1 and subsequent disinhibition of TRPV4, resulting in endothelial Ca2+ influx and vascular barrier failure. Ivacaftor prevents CFTR loss and may thus present a promising therapeutic strategy in ARDS due to severe pneumonia including COVID‐19.
Localization of Orphan GPCRs within the Liver
Authors: Kurtz Ryan , Shepard Blythe D. 
Published: May 2022

G protein‐coupled receptors (GPCRs) are the largest gene family in the genome and are involved in almost every aspect of physiology ranging from hormone receptors to eyesight. They also happen to represent the largest class of “druggable” molecules; in fact, 20‐30% of all FDA‐approved drugs on the market target GPCRs. Despite this, the vast majority of GPCRs remain underappreciated with incomplete expression patterns and characterization. These receptors, termed GPRs, have been linked to metabolic pathways and are known to respond to naturally produced metabolites. We reasoned that the liver, the largest metabolic organ in the body, is primed to take advantage of some of these GPRs in order to regulate its internal environment. To identify these receptors, we performed a large‐scale screen for over 300 GPCRs on whole murine liver using TaqMan qPCR array cards. This screen identified a total of 57 GPRs – with 7 of the them deemed to be “high expressing” with ΔCt values comparable to the more well‐characterized hepatic GPCRs (i.e. glucagon receptor). We confirmed expression of each of these GPRs (GPRc5c, GPR125, GPR146, GPR137, GPR116, GPR108, GPR17) via gene‐specific PCR from multiple murine liver samples.In order to characterize these understudied receptors within the liver, we must first understand where they are localized and what activates them. Given the dearth of reliable antibodies, we began by examining expression using RNAscope, a powerful in situ technique that specifically localizes mRNA sequences. GPR108, which has previously been linked to regulation of Toll‐Like Receptor signaling, was found within hepatocytes. GPR146, a known C‐peptide receptor which has been shown to impact blood cholesterol levels, was highly expressed in hepatocytes, and weakly localized to cholangioctyes and vessels. GPR109a, a highly studied receptor known to respond to short chain fatty acids and a potential therapeutic target for liver disease, was found to be primarily expressed in cholangiocytes, which notably play a key role in modification of bile. Finally, GPR125, an atypical adhesion GPCR, exhibited weak expression in hepatocytes but rather strong staining in select cholangiocytes and the liver vasculature. This was confirmed using both immunohistochemistry and immunofluorescence microscopy where we noted basolateral staining along the small cholangiocytes and hepatocytes. Given its localization and function as an adhesion receptor, GPR125 is well‐positioned within the liver to respond to, and to regulate, extracellular matrix proteins and their composition in both health and disease. Efforts are currently underway to deorphanize these receptors using the PRESTO‐Tango assay and to better understand their roles in the pathogenesis of metabolic diseases in the liver.
Metabolic Alterations in Aorta Induces Brain Cholesterolemia, Memory Loss and Cognitive Dysfunction in Diabetic Mice
Authors: Aluganti Narasimhulu Chandrakala , Singla Dinender 
Published: May 2022

AimDiabetic hyperlipidemia and associated cognitive dysfunction are of major concern and is essential to understand the mechanism and pathophysiology of diabetic brains, which remains unknown. In this study, we investigated whether hypercholesterolemia induces apoptosis and cognitive dysfunction, in diabetic apolipoprotein E (APOE) and paraoxonase 1 (PON1) double knockout (DKO) mice brains.HypothesisWe hypothesize that hypercholesterolemia induces apoptosis that involves cognitive dysfunction and furthers to Alzheimer’s.MethodsApoE‐PON1 DKO mice (6±2 months) were divided into control and STZ groups. At Day‐28, brain function, blood glucose, and serum lipids were measured followed by subjecting animals to Glucose Tolerance Test. Echocardiography was performed, and mice aortas were isolated. Brain‐parameters were examined using RT‐PCR, immunohistochemistry, and histologically.ResultsWe observed a significant (p<0.05) increase in blood glucose levels, serum lipids, increased aortic lesions, as well as increased cholesterol loading and apoptotic markers in brains of diabetic mice as compared to control. A significant reduction in reverse cholesterol transport, and HDL‐associated proteins were observed. A significant (p<0.05) decrease in brain weight, size, and brain function were observed in diabetic mice. Furthermore, a significant (p<0.05) increase in PTEN and decrease in AKT levels were observed in diabetic mice. In addition, a significant (p<0.05) increase in Alzheimer’s specific markers were also observed.ConclusionIn conclusion, our data suggest that hyperlipidemia induces apoptosis, that leads to neuronal cell death, memory‐loss, and cognitive dysfunction, which furthers Alzheimer’s in diabetic ApoE and PON1 DKO mice. Further therapeutic approaches require to be developed to target hyperlipidemia in diabetic brains.
Lights, Camera, PAKtion: Design and Engineering of a Subcellular Targeting Optogenetic PAK1 Kinase and Sensor
Authors: Kinney William D. , Haar Lauren , Lawrence David S. 
Published: May 2022

p21‐activated kinase 1 (PAK1) is a major ‘pathogenic kinase’ that directs cell motility, cytoskeletal remodeling and has been shown to function as a downstream regulator for various cancer signaling cascades. Such biological roles require a tight spatial and kinetic control of its localization and activity. Unfortunately, the spatiotemporal nature of these pathways renders the application of conventional tools inadequate for studying localized PAK1 induced cell behavior. Therefore, we have designed and engineered an optogenetic analog of PAK1 to address the difficulties in assessing PAK1 intracellular activity.Optogenetics is a powerful light‐triggered technology that, via control of protein biochemical activity, allows for the spatial and temporal control over a variety of biological processes. We developed an engineering strategy to construct a genetically expressed, light‐responsive optogenetic analog of PAK1 (optoPAK1) and demonstrated that, upon illumination, optoPAK1 migrates to specified intracellular sites. OptoPAK1 was designed to function independently of endogenous biochemical regulation in a constitutively active manner with minimal activity in the dark state. We employed the improved light‐induced dimer (iLid) system as a means to recruit and photoactivate the protein analog at discrete subcellular domains. Furthermore, we designed intracellular spatially segregated reporters of optoPAK1 activity and preliminary data displayed that optoPAK1 phosphorylates these reporters in a light‐dependent fashion. Taken together, optoPAK1 and its corresponding biosensor offer the opportunity to appropriately study the relationship between PAK1 compartmentalized biochemical activity and cell behavior.
Physiological Changes in Response to Skeletal Muscle Specific High Expression of mu‐Crystallin Following High and Low‐Fat Diets
Authors: Noland Kaila , O'Neill Andrea , Pimparkar Ujwala , Aja Susan , Bloch Robert 
Published: May 2022

Approximately 20 percent of the population expresses high levels of the thyroid hormone binding protein mu‐crystallin in skeletal muscle while the rest of the population expresses little to no mu‐crystallin. Since the thyroid hormones, T3 and T4, are potent regulators of metabolism and thermogenic regulation, our studies focus on the consequences of skeletal‐specific high expression (SM‐HE) of mu‐crystallin. We hypothesize that SM‐HE of mu‐crystallin influences cellular and metabolic changes in a diet‐ and sex‐ specific manner by influencing changes in gene expression.To evaluate this, we generated transgenic mice (Crym‐tg) that over‐express mu‐crystallin in skeletal muscle, equivalent to human high expressors, which resulted in high levels of accumulation of T3 in muscle tissue. Respiratory exchange ratio (RER) in these mice indicated a small but significant increase in utilization of fat as an energy source.In high‐ and low‐fat diet studies, we found differences between Crym‐tg and controls as well as sex specific differences. Following a 16‐week exposure, Crym‐tg males on high‐fat diet and Crym‐tg females on low‐fat diet weighed more than controls whereas Crym‐tg males on low‐fat diet and Crym‐tg females on high‐fat diet weighed less than controls. These differences were consistent with the results of glucose tolerance tests, in which only the Crym‐tg mice that weighed more than controls showed a significant increase in sensitivity to glucose. We are currently evaluating these results to understand their basis in transcriptomic and proteomic data, which have already revealed increased expression of genes involved in fatty acid oxidation and decreased expression of genes involved in glycolytic metabolism (Kinney et al. (2021) Curr Res Physiol. 4:47‐59.) as well as some members of the insulin signaling pathway.