bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impaired vasomotor function in uremic rats is directly related to NO‐resistance of smooth muscle cells
Authors: Kolk Felix , Molin D.G.M , De Mey J.G.R , Post M.J. 
Published: June 2021

The number of patients with renal failure is 240 million worldwide, with 20% being dependent on dialysis. Renal failure increases the risk to develop cardiovascular diseases and could be related to vessel wall dysfunction.Gaining a better understanding of arterial dysfunction under uremic conditions and especially its effect on NO‐soluble guanylate cyclase (sGC) mediated vasorelaxation.For uremic rats, 5/6 nephrectomy (n=21) was performed in Wistar rats. After six weeks, both carotid arteries were removed and analyzed in a wire‐myograph. Different compounds were used to investigate NO‐dependent and ‐independent vasomotor pathways.SNP and Deta NONOate showed significant differences in vasorelaxation between sham and 5/6 nephrectomy group with a 0.5 log IC50 difference in NO‐induced relaxation (P<0.0001). This difference was endothelial independent as acetylcholine induced effects were blocked with L‐NAME. Also NO independent, but sGC heam dependent and independent, (Bay 41‐2272 and Bay 60‐2770, respectively) vasorelaxation showed significant differences (p<0.01 and p<0.0001). When sGC was oxidized with ODQ, sham group was more potent in relaxation for both compounds as compared to uremic rats.Reduced vasorelaxation in uremic rats is related to NO‐resistance of smooth muscle cells. Our results point toward an oxidized state of sGC as the main cause of vasomotor dysfunction in uremic rats.
Impaired L‐arginine Uptake Contributes to Aortic Endothelial Dysfunction in Chronic Kidney Disease
Authors: Martens Christopher R , Kuczmarski James M , Lennon-Edwards Shannon , Edwards David G 
Published: June 2021

Reduced nitric oxide (NO) bioavailability contributes to endothelial dysfunction in chronic kidney disease (CKD) and is related to an increased cardiovascular disease risk. Vascular uptake of the NO substrate L‐arginine is attenuated under uremic conditions and may be an important mechanism of endothelial dysfunction in CKD. We sought to determine if impaired L‐arginine transport contributed to endothelial dysfunction in an animal model of CKD. 12 week old, male Sprague‐Dawley rats underwent 5/6 ablation/infarction (AI) surgery to induce CKD and were compared to a Sham control group. Endothelial‐dependent relaxation (EDR) of aortic rings to acetylcholine (Ach; 10−9–10−5M) was significantly impaired in AI vs. Sham after 8 weeks, demonstrated by an attenuated maximal response (65.02±5.02 vs. 102.10±4.94%, p < 0.0001) and rightward shifted LogEC50 (−6.659±0.121 vs. −7.707±0.111, p<0.0001) and was not improved by L‐arginine treatment. In support of this finding, expression of the L‐arginine transporter CAT‐1 was attenuated in CKD (relative to β‐actin, p=0.002) and appears to have resulted in reduced aortic uptake of L‐[3H]arginine (49.01±15.48 vs. 100.08±16.33 dpm/mg, p = 0.06). These preliminary data suggest that uremic inhibition of L‐arginine uptake may act as a novel mechanism by which endothelial dysfunction occurs in CKD and may be a potential therapeutic target to treat vascular dysfunction in CKD.Supported by: P20 RR016472
A kinetic model for sodium transport via a non‐gastric H+(Na+)/K+ ATPase
Authors: Nadal-Quiros Monica , Nieves-Gonzalez Aniel , Moore Leon C. , Marcano Mariano 
Published: June 2021

Experimental results have suggested that macula densa (MD) cells have a unique way of regulating cellular sodium concentration via an apical H+(Na+)/K+‐ATPase. We developed a kinetic model to represent the sodium transport via this transporter. The model assumes a 2:2 stoichiometry for both the hydrogen and sodium cycles. Rate constant values for the hydrogen cycle were obtained from a renal H+/K+‐ATPase model (A.M. Weinstein, Am J Physiol Renal Physiol 274:F856‐F867, 1998) which were, in turn, based on values obtained from a gastric H+/K+‐ATPase model (P. Brzezinski et al., Biochim. Biophys. Acta 942:215–219, 1988). Rate constants for the sodium cycle are assumed to be equal to those in the hydrogen cycle. Results showed that sodium extrusion is very sensitive to changes in luminal potassium concentration from 0 to 20 mM. In addition, sodium extrusion as a function of internal sodium concentration saturates at ~70 mM. This ATPase pump model is essential in the development of larger scale models of ion transport by the MD cells.Research supported by MBRS‐RISE grant 2R25GM061151‐09 and by NIH‐NIGMS grant SC1GM084744.
Renal extracellular matrix in three rat‐models of hypertensive kidney damage: A microarray study of SHR, SHRSP and 2K1C
Authors: Skogstrand Trude , McBride Martin , McClure John , Hultström Michael 
Published: June 2021

IntroductionThe aim of this work was to identify common genetic pathways in kidneys of three hypertensive rat models during development of kidney damage.MethodsKidney microarray expression profiles were determined from 60‐week‐old Spontaneously Hypertensive Rats (SHR) versus Wistar Kyoto (WKY); 21‐week‐old salt‐loaded Stroke‐Prone SHR (SHRSP), and 30‐week‐old Wistar rats with two kidney, one clip (2K1C) hypertension for 24 weeks versus sham‐operated controls.ResultsDifferentially expressed genes (FDR < 0.05: 2033 in 2K1C, 3721 in SHR, and 519 in SHRSP) identified 93 common between models. Top genes by rank‐sum were: SPP1, TIMP1, LCN2, COL3A1, WTAP, FN1, KIFC1, SLPI, MGP, TNFRSF12A. Analysis of gene ontology showed enrichment in extracellular matrix (p<2e‐8), cell‐substrate adhesion (p<0.001), defence response (p<1e‐4), and protein binding (p<0.005). Ingenuity Pathway Analysis identified cardiovascular inflammation (p<1e‐8) and renal injury (p<1e‐5) as two major activated pathways.ConclusionComparing three models of hypertensive kidney damage identify a common core of extracellular matrix and cell‐matrix binding genes activated during the development of kidney damage in hypertension.Funding from the Health Authority of Western Norway, Haukeland University Hospital Strategic Research, Lars Hiertas Minne, Magn. Bergvall, British Heart Founation.
Epigenetically‐induced systemic vascular dysfunction and hypertension in offspring of restrictive diet pregnancy in mice
Authors: Rexhaj Emrush , Rimoldi Stefano , Giacobino Ariane , Sartori Claudio , Allemann Yves , Scherrer Urs 
Published: June 2021

Children born from mothers with preeclampsia display generalized vascular dysfunction. In mice, hypoxia induces pulmonary vascular dysfunction by an epigenetic mechanism in offspring of restrictive diet pregnancy (RDP) (a model mimicking preeclampsia in humans). However, little is known regarding systemic vascular function in this model.We therefore assessed vascular function in vitro (mesenteric artery) and in vivo (blood pressure, carotid artery) in offspring of RDP (12 wks) and control mice.In offspring of RDP, endothelium‐dependent mesenteric‐artery vasodilation in vitro was markedly impaired (P<.0001 vs. control) and was associated with arterial hypertension in vivo (119±7 vs. 112±5 mmHg, X±SD, P=.04 vs. ctrl). To test for an epigenetic mechanism, we examined DNA methylation of imprinted genes and the promoter of the eNOS gene in the aorta of male offspring of RDP and control mice. In offspring of RDP the DNA methylation of imprinted genes Peg3 (P<.03), Snrpn (P<.03), Gtl2 (P<.01) and the promoter of the eNOS gene (P= .01) were altered compared to control mice. This vascular dysfunction was transmitted to the next generation further suggesting an epigenetic mechanism.We demonstrate for the first time that RDP induces systemic vascular dysfunction by an epigenetic mechanism. We speculate that in humans, preeclampsia induces vascular dysfunction by a similar mechanism.
Dexamethasone Differentially Regulates Blood Pressure in Transgenic Mice Containing ‐217A/G Polymorphism of Human Angiotensinogen Gene
Authors: Pandey Varunkumar G. , Jain Sudhir , Maharjan Shreekrishna , Mopidevi Brahmaraju , Arudra Sri Krishna Chaitanya , Kumar Ashok 
Published: June 2021

The human angiotensinogen (hAGT) gene locus is associated with hypertension. Earlier studies have shown that hAGT gene has an A/G polymorphism at ‐6 position and ‐6A allele is associated with increased blood pressure. We have shown that this gene also contains an A/G polymorphism at ‐217, and frequency of ‐217A allele is increased in African‐American hypertensive patients. Nucleotide sequence of hAGT gene promoter containing ‐217A has homology with the consensus CCAAT/enhancer binding protein (C/EBP) and GR binding site. Our in vitro studies show that dexamethasone (Dex) differentially increases the promoter activity of plasmid containing haplotype ‐217A as compared to the plasmid with haplotype ‐217G. Therefore, we have generated transgenic mice containing either haplotype ‐217A or ‐217G of the hAGT gene. These transgenic mice were treated with Dex (25ug/mL in drinking water) for 1 week. We found that mice containing haplotype ‐217A has 2.3 fold and 3.5 fold dex induced expressioin of hAGT in liver and kidney respectively whereas no significant changes were observed in haplotype ‐217G. Additionally, the SBP of mice containing haplotype ‐217A increases by 15mmHg after Dex treatment as compared to 6mmHg in the mice containing haplotype ‐217G. Results from these experiments suggest that glucocorticoids may cause differential increase in blood pressure in individuals with ‐217A haplotype as compared to those with ‐217G haplotype.Supported by NIH grants to AK
Epigenetic control of lung fluid clearance
Authors: Wujak Lukasz Andrzej , Becker Simone , Arnoldt Verena , Morty Rory Edward 
Published: June 2021

The Na,K‐ATPase regulates ion transport and alveolar fluid clearance (AFC) in the lung. TGF‐β mediates acute lung injury (ALI), and impacts AFC. We hypothesized that TGF‐β impacts Na,K‐ATPase activity by modifying subunit stoichiometry. Cell surface density of the Na,K‐ATPase is regulated by the ATP1B1 subunit. ATP1B1 expression was reduced both in TGF‐β‐treated lung epithelial cells and in lungs from ALI patients or mice with experimental (bleomycin‐induced) lung injury. Luciferase, surface biotinylation and 86Rb+ uptake assays demonstrated that TGF‐β reduced Na,K‐ATPase gene expression, activity, and cell‐surface density, respectively, in primary lung epithelial cells. RNA interference and chromatin immunoprecipitation studies revealed that ATP1B1 downregulation relied on SMAD4, SNAI1 and E2F5 transcription factors, and was critically dependent on HDAC2. The HDAC inhibitor, Trichostatin A, improved edema resolution in experimental lung injury. Collectively, our data suggest that TGF‐β downregulates ATP1B1 expression leading to decreased Na,K‐ATPase activity and consequently impaired AFC in ALI, and that these processes can be reversed by HDAC inhibition.German Research Foundation
AMPK activation by AICAR induces mitochondrial biogenesis in the inner ear
Authors: Nuttall Alfred L. , Wilson Teresa , Omelchenko Irina , Shi Xiaorui 
Published: June 2021

RationaleThe importance of mitochondrial biogenesis to auditory hair cell physiology or that of the non‐sensory cells in the cochlea is poorly understood. Activation of 5′ AMP activated protein kinase (AMPK) upregulates peroxisome proliferator–activated receptor‐γ coactivator‐1α (PGC‐1α) which, in turn, increases the levels of factors involved in mitochondrial biogenesis and respiration. At the same time, AMPK activation can increase antioxidant expression and reduce reactive oxygen species generation.ObjectiveTo determine whether the AMPK activator 5‐aminoimidazole‐4‐carboxamide‐1‐β‐D‐ribofuranoside (AICAR) can induce mitochondrial biogenesis in the inner ear and protect against noise induced hearing loss.Methods and ResultsAICAR treatment in mice led to higher levels of phosphorylated AMPKα in the cochlea by immunoblot and immunohistochemistry (IHC) analysis. Quantitative real‐time PCR revealed increased PGC‐1α mRNA levels. Extended AICAR treatment increased mitochondrial fission protein 1 and superoxide dismutase 2 protein levels. Auditory brainstem response analysis demonstrated that AICAR treatment accelerated recovery from acoustic trauma.ConclusionThese results demonstrate that mitochondria in the inner ear have the capacity to be dynamically regulated with increasing energy demands.Supported by grants 5R01DC000105 (ALN), 1R01DC010844 (XS), and P30DC005983.
Decreased expression of Wnt9b and Ube2ql1 in the face of CL/Fr mouse embryos at E11.5 based on microarray analysis
Authors: Takagi Brennan Nicholas , Hynd Thomas , Somponpun S. Jack , Nonaka Kazuaki , Lozanoff Scott 
Published: June 2021

The CL/Fr mouse demonstrates heritable bilateral and unilateral cleft lip and palate (CLP) at a rate of approximately 35%, generally above the background “A” strain mouse. Using classical mouse breeding strategies, it has been suggested that at least two disease loci, clf1 and clf2, are involved in the defect and candidate genes have been identified. Additionally, gene‐targeting analyses strongly suggest that Wnt9b contributes to CLP in the “A” strain mice. The aim of this study was to test the expression of clf1 and clf2 candidate genes in the facial prominences of CL/Fr embryos, utilizing microarray analysis. Medial nasal, lateral nasal, and maxillary prominences of phenotypically normal as well as cleft E11.5 CL/Fr mice were dissected and RNA was extracted using standard techniques for Agilent‐microarray protocol. Results indicate that expression of the clf1 candidate gene, Wnt9b, and the clf2 candidate gene, Ube2ql1, are significantly reduced (−3.11 and −1.83 fold, respectively) in the CL/Fr cleft tissues, suggesting these genes may be involved in the CLP mutation in CL/Fr mice. Future gene expression studies through quantitative RT‐PCR and regional expression analyses through immunohistochemistry and whole mount in situ hybridization will be performed to further test the expression of these clf1 and clf2 candidate genes.Grant Funding Source: NIH/NCRR 5P20RR024206 (S.J.S) and R01‐DK‐064752 (SL)
Effect of Thyroid Hormone Exposure on Murine Calvarial Derived Pre‐Osteoblasts
Authors: Cray James John , Weinberg Seth M , El-Salanty Mohammed 
Published: June 2021

Craniosynostosis (CS) is the premature fusion of one or more of the fibrous joints of the skull, which normally allow for the growth of the neurocranium. The incidence of CS is one in every 2000–3000 births. CS involves the overgrowth of bone at the osteogenic fronts of the developing cranial bones. The etiology of CS, whether genetic or environmental, is unknown for the majority of cases. Little is known about the role of environmental agents or gene‐environment interactions in modulating CS phenotypes. The clinical and epidemiological literature suggests that maternal hyperthyroidism is a risk factor associated with CS in offspring, however the mechanism of action is unclear. Here we provide a preliminary report of the effects of exogenous thyroid hormone exposure on cells derived from murine calvaria. Murine derived calvarial cells were assayed for proliferation and osteogenic differentiation after 24,72, 168 hours in culture with exogenous thryoxine at doses ranging from 10^−4 and 10^−16 mol. Exogenous exposure to thyroid hormone appears to stimulate cells to express higher levels of alkaline phosphatase (ALP) in a dose dependent manner. These differences reach 5 times the amount of ALP activity after exposure to the highest doses. There does not appear to be a pattern of difference for proliferation. Thus, it appears thyroid hormone may exert its effects on sutures by increasing the activity of osteoblasts.Grant Funding Source : None
Presence of Carbamazepine in Drinking Water Does Not Appear to Cause Neural Tube Defects in Mice
Authors: Melin Vanessa , Hrubec Terry , Magnin-Bissel Geraldine , Blodgett Dennis , Etzkorn Felicia 
Published: June 2021

In May of 2006, our lab suddenly began to observe neural tube defects (NTDs) in embryos of untreated control mice. Exposure to a teratogenic agent in tap water was identified as the cause. Pharmaceuticals have emerged as ubiquitous contaminants of drinking water. One such NTD inducing drug, carbamazepine (CBZ), was analyzed. CBZ was detected in several ground, surface, and tap waters, ranging in concentrations from 0.28 ng/L to 9.5 ng/L. To test whether CBZ was responsible for NTDs, we exposed mice to CBZ in 2 water types. In well water, CBZ concentrations were at 15 and 1500 ng/L. In double distilled water, CBZ concentrations were at 6 and 1500 ng/L. Both studies found no significant differences in NTD rates among the dose groups. As no dose effect was observed, we concluded that CBZ was not directly responsible for the malformations; however it is possible a mixture of contaminants, including CBZ, may be involved.Grant Funding Source : NIH‐NIHSR21E5016886‐01
Analytic view of simultaneous occurrence of sacralisation and congenital anomalies
Authors: Singh Rajani 
Published: June 2021

Lumbar and coccygeal sacralisation may be defined as fusion of fifth lumbar vertebra with first sacral vertebra at the cranial end and apex of sacrum with first coccygeal vertebra at the caudal end respectively. The modulated mutation of HOX11and PAX1/9 families caused defective sacralisation with simultaneous occurrence of anomalies in organs like hindlimb, forelimb, thymus, parathyroid etc in mice. Therefore an attempt has been made to extend the study of sacralisation and associated anomalies from mice to men by conceiving a Hypothesis to be established by future experimentation.66 dry human sacra were studied in the Osteology laboratory of CSM Medical University Lucknow, UP, India. The defective sacra were genetically analysed and corroborated with experimental results from mice. These sacra were correlated with the mutation of the HOX11and PAX1/9 genes expression and complemented with the associated anomalies as in mice.The study may revolutionize the clinical practice and diagnosis.No financial support could be obtained from any source by author.Grant Funding Source: N/A
Primary osteoblasts colonize and mineralize 3D nanofibrous gelatin scaffolds in 14 days
Authors: Sachar Ashneet , Strom Amanda , Serrano Maria , Miguel Symone San , Liu Xiaohua , Svoboda Kathy K.H. 
Published: June 2021

To enhance the outcome of bone tissue engineering, it is important to understand the interactions between osteoblasts and scaffolds. In this study, we analyzed and quantified cell‐matrix interactions and tissue formation by primary cultured osteoblasts on 3D nanofibrous gelatin scaffolds (3D‐NF‐GS) using confocal microscopy. 3D‐NF‐GS were cultured with osteoblasts for 5 or 14 days and immunolabeled with specific antibodies: Integrin b1, vinculin, tyrosine phosphorylated paxillin and collagen type I. A Leica Confocal SP5 microscope was used to analyze the protein distribution. Alizarin red staining was used for mineral detection. Osteoblasts on 3D‐NF‐GS exhibited uniform migration by 5 days and the cells proliferated to an increased confluence by the 14th day. They adhered to 3D‐NF‐GS via focal adhesions by 5 days demonstrated by integrin b1, vinculin and phosphorylated paxillin. Integrin b1 and phosphorylated paxillin adhesions increased in number by 14 days and vinculin adhesions turned more fibrillar. The osteoblasts started arranging into nodular aggregations by 14 days and abundant mineralization of 3D‐NF‐GS was documented. In conclusion, osteoblasts’ adhesion, migration and proliferation on 3D‐NF‐GS lead to secretion of the primary osteoid protein, type I collagen and matrix mineralization. This demonstrates favorable osteoblast behavior on this 3D matrix material.Grant Funding Source: NIH/NIDCR P30 DE020742
High‐throughput screening for Plasmodium falciparum glucose‐6‐phosphate dehydrogenase‐6‐phosphogluconolactonase inhibitors
Authors: Preuss Janina , Hedrick Michael , Sergienko Eduard , Pinkerton Anthony , Jortzik Esther , Rahlfs Stefan , Becker Katja , Bode Lars 
Published: June 2021

During malaria infections, there is a significant increase in the pentose phosphate pathway activity of Plasmodium falciparum (1). In addition, its key enzyme, glucose‐6‐phosphate dehydrogenase‐6‐phosphogluconolactonase (PfGluPho), shows structural differences to the human enzyme, thus making PfGluPho an ideal target for antimalarial drug design (2). Recent cloning and overexpression (2) of recombinant PfGluPho allowed investigations in a high throughput format. We were able to develop a high‐throughput screening assay to identify inhibitors for PfGluPho. Three small molecule compound libraries were screened, namely LOPAC™ (Sigma‐Aldrich, 1,280 compounds), Spectrum™ (Microsource discovery system, ~2,000 compounds), and DIVERSet™ (ChemBridge, ~50,000 compounds), which resulted in ~900 compounds that inhibited PfGluPho activity for at least 50%. Selected compounds were subjected to follow‐up studies, including IC50 determination and mechanistic characterization. The availability of recombinant PfGluPho, its major differences to human G6PD, and the identified inhibitors facilitate further studies on PfGluPho as excellent drug target candidates for the search of new antimalarial drugs.Supported by NIH 1R21AI082434‐01
IL‐35 is a Novel Responsive Anti‐inflammatory Cytokine ‐ A New System of Categorizing Anti‐inflammatory Cytokines
Authors: Li Xinyuan , Mai Jietang , Virtue Anthony , Wang Hong , Yang Xiao-Feng 
Published: June 2021

Interleukin‐35 (IL‐35), a recently discovered heterodimeric cytokine with anti‐inflammatory/immunosuppressive properties, has a central role in limiting the immune response in various disease models including colitis, arthritis and asthma. However, it remains unknown whether IL‐35 is different from other anti‐inflammatory cytokines such as IL‐10 and transforming growth factor (TGF)‐β in terms of inhibition of inflammation initiation or suppression of full‐blown inflammation. In this study, we examined the tissue expression profiles and regulatory mechanisms of IL‐35 in comparison to other anti‐inflammatory cytokines. Our results suggest that in contrast to TGF‐β, IL‐35 is not constitutively expressed in human tissues but is inducible in response to inflammatory stimuli. We also provide structural evidence suggesting that AU‐rich element (ARE) binding proteins and microRNAs target IL‐35 subunit transcripts, which are responsible for quick degradation of IL‐35. Furthermore, we propose a new system to categorize anti‐inflammatory cytokines into two groups: (1) the housekeeping cytokines, such as TGF‐β, inhibit the initiation of inflammation whereas (2) the responsive cytokines including IL‐35 suppress inflammation in full‐blown stage. Our in‐depth analysis of molecular events that regulate the production of IL‐35 and new categorization system of anti‐inflammatory cytokines are important for the design of new strategies of immune intervention.This work was partially supported by the National Institutes of Health Grants HL094451 and HL108910 (XFY), HL67033, HL82774 and HL77288 (HW).