bluuebunny/crossref_metadata_2025_split huggingface dataset:
Control of Cardiac Fibroblast Phenotype by the Meox2/Zeb2 Signalling Switch (LB47)
Authors: Jahan Fahmida , Northcott Josette , Cunnington Ryan , Cheung David , Rattan Sunil , Filomeno Krista , Dixon Ian , Wigle Jeffrey 
Published: June 2021

The fibroblast to myofibroblast phenoconversion, which is induced by TGF‐β, is a crucial step during cardiac fibrosis. Activated myofibroblasts increase extracellular matrix (ECM) synthesis, which impairs contraction that results in myocardial stiffening, and eventually heart failure. Meox2, a regulator of cell proliferation and senescence, can block TGF‐β mediated epithelial to mesenchymal transition (EMT). In contrast, Zeb2, a repressor of Meox2, enhances EMT in concert with TGF‐β. However, their roles in the fibroblast to myofibroblast phenoconversion remain elusive. We have shown that Meox2 is more highly expressed in fibroblasts than in myofibroblasts. Conversely, Zeb2 expression is lower in fibroblasts but higher in myofibroblasts. This suggests that Meox2/Zeb2 may regulate the fibroblast phenotype during cardiac fibrosis. We have shown that ectopic expression of Meox2 represses a set of myofibroblast markers. We have successfully knocked down Meox2 protein in primary cells. By confocal microscopy, Meox2 protein was found to be confined to the nuclei of fibroblasts whereas a cytoplasmic distribution was seen in myofibroblasts. By immunoblotting, Zeb2 expression was found to be higher in the nuclei of myofibroblasts. To test if ectopic Zeb2 expression enhances this phenoconversion, we have recently generated an adenoviral Zeb2 expression construct. We anticipate that the Meox2/Zeb2 signalling switch plays a critical role in cardiac fibrosis and findings from this study may provide a basis for developing Meox2 or Zeb2 based novel anti‐fibrotic drugs in the future.Grant Funding Source: Supported by Canadian Institutes of Health Research & Heart and Stroke Foundation of Canada
The migration of radionuclide’s for the sanitary protection zone of uranium tailings enterprises (LB488)
Authors: Kazymbet Polat , Bakhtin Meirat , Kashkinbaev Erlan , Dzhumadilov Kasym , Eltokova Manshuk , Ribalkina Dina 
Published: June 2021

Mining companies are potential sources of contamination of the environment by various pollutants, including technogenic radionuclides. Stepnogorsk Mining‐Chemical Combine (SMCC) functions over 50 years and is one of the largest complexes for production of uranium oxide and other rare metals. Radioactive waste of SMCC is accumulated in the tailing dumps with an area of 7.82 km2, located in 4 km to the North from Aksu village and Zavodskoy, where concentrated waste is with a mass of 44.17 million tons, and activity of 146.4 thousand Ku. The aim of this work was to evaluate the radiological situation of territories for sanitary protection zone of the tailings dumps (SZZH), including those in close vicinity to workers of the villages Aksu and Zavodskoy.As a result of the pedestrian gamma survey there were identified local, contaminated sites in the North‐East of SZZH SMCC with a length of 5 km. The most contaminated with radionuclides is the top layer of the soil 0‐5 cm. in the North‐East and South‐East direction from SZZH specific activity is 238U, 226Ra in the soil exceed the reference value in 16 times, 210Pb exceeds up to 7 times. In the samples of plants selected from the vicinity of villages in the South‐East and North‐East directions from SZZH it is noted high concentrations of natural radionuclides. In reservoirs of Sulukamys and Manybay thalwegs, located at a distance of 1.5 to 2 km in the Eastern and North‐Eastern part of the tailings dumps, the specific activity of technogenic radionuclides in the tens times higher than control values.On the territory of the village Aksu there were identified local, contaminated sites with a capacity of an equivalent dose of gamma radiation up to 0.86 mSv / h Possible additional radiation dose from external exposure for separate groups of the population of Aksu is from 0,86 mSv to 1,53 mSv per year.
Akebiae caulis extract inhibits oxidative stress through AMPK/GSK3‐beta pathway (LB551)
Authors: Kim Young Woo , Jung Eun Hye , Byun Sung Hui , Kim Sang Chan , Cho Il Je 
Published: June 2021

Akebiae caulis is commonly used for the oposiuria, inflammation, nociceptive and fever. We investigated the effect of Akebiae Caulis extract (ACE) to protect cells against the mitochondrial dysfunction and apoptosis. Arachidonic acid (AA)+iron promotes excessive reactive oxygen species production and dysfunction of mitochondria. ACE protected hepatocytes from AA+iron‐induced cytotoxicity. As a potential molecular mechanism for the ACE‐mediated cytoprotection, phosphorylation of AMPK, a key regulator in determining cell survival or death, was increased by ACE. Moreover, ACE treatment enhanced inactive phosphorylation of GSK3β, downstream substrate kinase of AMPK. ACE also prevented a decrease in the GSK3β phosphorylation derived by AA+iron, which might contribute to mitochondrial protection and cell survival. Moreover, we found that betulin in combination with hederagenin protected from AA+iron‐induced mitochondrial dysfunction. These results show that ACE has the ability to protect cells against AA+iron‐induced H2O2 production and mitochondrial impairment, which is mediated with inactive GSK3β phosphorylation downstream of AMPK.Grant Funding Source: This work was supported by the National Research Foundation of Korea grant funded by the Korea government [MEST](No.2012‐0009400).
The G Protein‐Coupled Estrogen Receptor 1 Regulates Endothelial Ca2+ efflux via the plasma membrane Ca2+‐ATPase. (LB568)
Authors: Tran Quang‐Kim , Burgard Michelle , VerMeer Mark , Giles Jennifer 
Published: June 2021

The G protein‐coupled estrogen receptor 1 (GPER) has been demonstrated to have a vast array of cardiovascular effects. Ca2+ extrusion via the plasma membrane Ca2+‐ATPase (PMCA) plays important roles in Ca2+ homeostasis. We tested the hypothesis that GPER is involved in the regulation of calcium efflux in the vasculature. In primary vascular endothelial cells, the specific GPER agonist G‐1 dose‐dependently inhibits PMCA activity. Knockdown of GPER in endothelial cells using antisense directed against GPER is associated with a ~ 40% enhancement of PMCA activity. Heterologous expression of human GPER in fusion with the fluorescent protein DsRed2 in HEK 293 cells results in a 38% reduction of PMCA activity. Co‐IP experiments show that PMCA and GPER form a complex during Ca2+ signals triggered by the SERCA pump inhibitor thapsigargin in endothelial cells. In addition, the fusion proteins PMCA‐DsRed2 colocalizes with GPER‐ECFP heterologously expressed in HEK 293 cells. These data suggest that GPER regulates Ca2+ efflux in endothelial cells by interacting with PMCA.Grant Funding Source: National Institutes of Health
Regulation of Store‐Operated Ca2+ Entry in the Vascular Endothelium by the G Protein‐coupled Estrogen Receptor 1 (LB570)
Authors: Terry Lara , VerMeer Mark , TRAN Quang‐Kim 
Published: June 2021

The novel G protein‐coupled estrogen receptor 1 (GPER/GPR30) has been found to participate in numerous cardiovascular functions. Store‐operated Ca2+ entry (SOCE) is an essential mechanism that is required for many endothelial cell functions. We found that activation of GPER using the GPER specific agonist G1 causes a dose‐dependent inhibition of SOCE in primary vascular endothelial cells. Heterologous of GPER in HEK 293 cells is associated with substantial decreases in the total Ca2+ signal triggered by thapsigargin, and a 40% decrease in the rate of SOCE. Knockdown of GPER in endothelial cells using antisense directed against GPER increases SOCE by approximately 50% compared to cells transfected scrambled oligo. Interestingly, GPER specific antagonist G15 triggers total Ca2+ signals via SOCE by releasing the same internal Ca2+ stores as does thapsigargin. In primary endothelial cells, GPER forms a complex with the stromal interaction molecule 1 (Stim1), an essential molecular switcher of SOCE. In addition, Stim1‐ECFP colocalizes with GPER‐tetracysteine when heterologously expressed in HEK 293 cells. Heterologous expression of GPER‐DsRed2 fusion substantially decreases total Ca2+ signal stimulated by thapsigargin. Interestingly, SOCE measured in cells stably expressing fusions between EYFP and individual sub‐membrane domains (SMDs) 1 ‐ 4 of GPER does not differ from internal controls. These data indicate that GPER may be an important regulatory input of store‐operated Ca2+ entry via its interaction with Stim1. Since the EYFP‐SMD fusions are all cytoplasmically expressed, the data may also suggest that proper membrane docking (PM or ER) of full‐length GPER is required for it to exert its effect on SOCE.Grant Funding Source: National Institutes of Health
Gravin‐mediated PKC signaling in heart (LB571)
Authors: Suryavanshi Santosh , Singh Sonal , McConnell Bradley 
Published: June 2021

Gravin is an A‐Kinase Anchoring Protein (AKAP) that scaffolds protein kinase A (PKA), protein kinase C (PKC), phosphatase 2B, β2‐adrenergic receptors to specific subcellular compartments. Studies show that scaffolding of PKC by gravin decreases PKC activity due to sequestration. Also, PKC is involved in the translocation and distribution of gravin. Our goal is to study the role of gravin in PKC signaling in the heart. Basal PKC activity in the cytosolic fractions of the homogenized hearts was found to be greater in gravin truncated (t/t) mice as compared to wild type (WT). This correlation was preserved following stimulation of the samples with a PKC activator, PMA (Phorbol 12‐myristate 13‐acetate). However, no change was observed in the extent of PKC substrate phosphorylation between these groups. It supports previous studies that PKC scaffolding by gravin decreases PKC activity. The next step is to study the effect of PKC on gravin translocation in cardiomyocytes using PKC activator PMA and inhibitor chelerythrine. We expect to see increased translocation of gravin to cytosol after PKC activation. These studies will help us better understand the functional significance of the role of gravin in PKC signaling.Grant Funding Source: R01HL085487
Determination of the IC50 and LD50 of Calcium Sulfide (CaS) Clusters on Malignant Carcinoma and Normal Fibroblasts Cell Lines (LB580)
Authors: Manoharan‐Valerio Michael , Ortiz Carlos , Quiñones Jaileen , Feliciano Geishamarie , Diaz Angel , Rivera Daniel , Castro Miguel , Suarez Edu 
Published: June 2021

Preliminary results in our lab showed that naked Calcium Sulfide (CaS) nanoparticles (5.0nm) decreased cell proliferation in the carcinoma cell lines CRL‐2124. Objective: The objective of this study was to determine the IC50 and LD50 for CaS clusters (measuring < 3.0 nm) in the carcinoma cell lines CRL‐2124 and the normal fibroblasts CRL‐2522 by using the n3D BiOAssay (Biosciences, Inc.). Methods: A total of 100,000 cells per cell line were seeded in T‐75 flasks. When reaching 80% confluence, they were incubated with the n3D nano‐shuttles overnight (ON) at 37oC, 5% CO2, and 98% relative humidity. Next day, cells were trypsinized, counted, and seeded (1.4 ‐ 1.6 M/per well) in 6‐well plates using the n3D BiOAssay to levitate the cells. A total of 150,000 cells/well were seeded in a 96‐well plate in triplicates with a total volume of 300ul (150ul of cells, 120ul of media, and 30ul of the treatments). The treatments consist of doses ranging 10‐100 pmoles of CaS, 2% DMSO, or growth media. A 24‐hours recording consisting of four (4) photos per minute was collected with an iPod. The analyses were performed using the ImageJ software by measuring the “O” ring outer and inner diameters. Results: We observed changes in the diameters for the wells treated with CaS at different concentrations when compared to controls. Conclusions: We determined the IC50 and LD50 for adenocarcinoma and normal fibroblast cell lines. This step is important for the translation of the use of CaS as an anti‐cancer therapy when translated into in vivo models.Grant Funding Source: NIH‐NIGMSR25GM096955, NIH‐R25GM088023
In vivo Anti‐ulcer and Antioxidant Enzyme Effect of Partially Purified Leaf Extract from Labisia Pumila in Indomethacin‐ Induced Ulcer Animal Model (LB585)
Authors: Okechukwu Patrick , Siyumbwa Stepfanie , Nomishan Ngizan 
Published: June 2021

This study is aimed at investigating the effect of partially purified leaf extract of Labisia Pumila (LP) on Indomethacin (IND) induced ulcer and on selected antioxidant enzymes: ‐ catalase (CAT), glutathione (GSH), superoxide dismutase (SOD) and lipid peroxidation(LPO). Column chromatography was used to partially purify the DCM crude extract into 4 fractions (A, B, C and D). 10mg/kg Indomethacin was administered for 5 days to induce ulcer. The oral administration of the LP fractions (A, B, C and D) at a concentration of 100mg/kg were found to inhibit IND induced gastric lesions by 67.5%, 27.2%, 47.82% and 66.2%, respectively, the effect was highest in fraction A and D. The level of antioxidant activity was enhanced by the oral administration of fractions A and D, the other fractions did not show any significant antioxidant activity. In conclusion, the oral administration of LP fractions A to D showed antiulcer activities in IND induced ulcer and fractions A and D enhanced the antioxidant activities in ulcer models.Grant Funding Source: UCSI University
Validation of new venom protease assays for translational research (LB589)
Authors: Price Joseph 
Published: June 2021

Snake envenomation is an understudied significant world health problem, designated an orphan disease by the WHO. In the U.S. lives are usually saved, but significant tissue is often lost. Overseas without hospitalization and antivenin, lives are forfeit. For most American snake venoms the major pathologies of tissue loss and coagulopathies are due to proteolytic degradation of host tissues and plasma cascades. For HTS leading to therapeutics including drug repurposing, sensitive new substrates may finally allow direct comparisons of venom activities, but only if the reptile enzymes are active upon them, which has been not previously been published. Here I show direct comparisons of representative American venoms strong protease and collagenase, but weak elastase activities using the new technology. Assay CV range 1‐5%. Caseinolytic activity is inhibited by the nonspecific protease inhibitor 1,10‐phenanthroline and by EDTA. So is collagenase activity, consistent with the action of matrix metalloproteases. The Km measured shows that high throughput assays could be done at substrate levels well below the Km for the reaction. Such a system will be invaluable for the testing leading to the repurposing of drugs to treat envenomations.Grant Funding Source: Supported by CHS‐OSU
Methamphetamine‐induce neurotoxic effects in rat c6 glioma cell (LB620)
Authors: Wiley Chantel 
Published: June 2021

PURPOSE: Methamphetamine (MA) is a potent, highly addictive central nervous system stimulant. It has been classified as a Schedule II drug, which makes it legally available, but only through a no refillable prescription. MA addiction has become a major public concern because its chronic abuse is associated with serious, yet fatal side effects such as memory loss, stroke, hyperthermia, and convulsions. These complex complications of the central nervous system may be related to a MA‐induced neurotoxic effect, which include damage to the dopamine system, activation of microglial and astrogial cells, and ultimately destruction of specific brain regions in humans. The present study seeks to investigate the cellular events associated with cytotoxic effects of MA in the Rat C6 glial cells. METHOD: Using the crystal violet assay to quantitate cell viability, methamphetamine at various concentrations (0.1 mM, 0.5 mM, 1 mM, 3 mM, and 5 mM) was exposed to the glial cells for 1, 24 and 48 hrs. To measure the morphological alterations after MA exposure, FITC Annexin V flow cytometry was used to distinguish cells that were in early and late stage of apoptosis. RESULTS: MA was found to have a dose and time dependent effect on cell viability. In addiction, the FITC Annein V Flow cytometry data revealed that as the concentrations increased more cells underwent apoptosis. These results revealed that MA not only cause a decrease in viability among C6 glioma cells, but is also the causes of the cellular demise was through the action of apoptosis. CONCLUSION: Further studies are underway to elucidate the mechanism by which MA induces apoptosis. The data generated from this study has provided some significant findings regarding the cellular mechanism of MA‐induced cytotoxicity in the Rat C6 glial cells. Moreover, our results can lead to potentially safe therapeutic treatments for neurodegenerative disorders that are associated with chronic drug use.Grant Funding Source: Research supported by NIMHD of the National Institutes of Health NIH under Award Number G12MD007582
Role of C‐jun N‐terminal Kinase in the Mitochondria of Ischemia‐Reperfusion Injury of Isolated Heart (LB648)
Authors: Jang Sehwan , Soto Jessica , Agostini Bryan , Javadov Sabzali 
Published: June 2021

Background: Previous studies indicate that inhibition of JNK activation during heart reperfusion reduces cell death and infarct size. However, the studies could not eliminate off‐target effects due to the use of non‐specific JNK inhibitors. In the present study, we observed whether two mechanistically unrelated, specific JNK inhibitors, SU3327 and SR3306, would reduce damage from ischemia/reperfusion (IR) and improve cardiac function.Methods: Using the Langendorff model of ischemia‐reperfusion, isolated rat hearts underwent 25 min of global ischemia followed by concurrent JNK inhibitor administration (2 and 10 µM for SU3327, 0.5 and 2 µM for SR3306) and 30 or 60 min of reperfusion. Throughout perfusion, we monitored cardiac function based on the percent recovery of left ventricular developed pressure, minimum and maximum rates of pressure change in the ventricle, and the rate pressure product. Myocardial damage was assessed by measuring lactate dehydrogenase activity in heart effluent. At the end of reperfusion, we used isolated mitochondria to determine respiration rates and mitochondria permeability transition pore opening. Proteins from the heart homogenate were analyzed using Western blot.Results: Our results indicate that the specific JNK inhibitors did not improve cardiac function. As expected, mitochondrial respiration control index was correlated to recovery of heart function. We observed marginal reduction of myocardial damage by JNK inhibitor SU3327 at the 10 min time point after reperfusion. Western blot analysis demonstrated inhibition of phospho‐JNK and total‐JNK at high doses (10 uM) of SU3327, but it coincided with activation of p38.Conclusion: JNK inhibition may provide cardioprotection against IR. However, in practice, it may be ineffective due to compensatory activation of p38 by an unknown mechanism.Grant Funding Source: Supported by SC1HL118669 (to S.J.), and in part, G12RR‐03051 NIH grants.
Pannexin‐1 regulates eNOS activation through a superoxide‐dependent pathway (LB652)
Authors: Lillo Mauricio , Gaete Pablo , Figueroa Xavier 
Published: June 2021

Pannexin‐1 (Panx1) is expressed in smooth muscle and endothelial cells of resistance arteries. In smooth muscle, Panx1‐formed channels mediate the α1‐adrenergic receptor‐initiated constriction, but the function of Panx1 in endothelial cells has not been determined. We analyzed the participation of Panx1 in the NO‐mediated dilation induced by the endothelium‐dependent vasodilator acetylcholine (ACh) in rat mesenteric resistance arteries contracted with 70 mM KCl. The activating phosphorylation of eNOS at serine 1177 (P‐eNOSS1177) and Akt at serine 473 (P‐AktS473) was evaluated by Western blot and superoxide production was detected using dihydroethidine. Blockade of Panx1 channels with probenecid, but not connexin‐formed hemichannel inhibition with La+3, enhanced the ACh‐induced vasodilation. Consistent with this, treatment with Panx1 channel blockers, probenecid or the mimetic peptide 10Panx, elicited an increase in P‐eNOSS1177, which was associated with a rise in P‐AktS473 and superoxide production. This effect of Panx1 blockers was not altered by ACh stimulation and was abolished by TEMPOL, a superoxide dismutase mimetic. It has been shown that superoxide production can lead to Akt activation by P‐AktS473. Therefore, these results indicate that Panx1 controls eNOS activity. Panx1 channel blockade initiates a superoxide‐dependent pathway that elicits Akt‐mediated eNOS activation via P‐eNOSS1177.FONDECYT 1100850
Extracellular Matrix Controls Notch Signaling via Integrin Activation and NICD Ubiquitination. (LB67)
Authors: Albig Allan , Malik Arpita , DeFord Peter , Westover Katherine 
Published: June 2021

The extracellular Matrix (ECM) has recently been implicated with the regulation of angiogenesis via manipulation of the Notch signaling system however the molecular basis for this has not been explored. We previously showed that the ECM protein microfibril‐associated glycoprotein 2 (MAGP2), suppresses Notch signaling in endothelial cells but promotes Notch signaling in non‐endothelial cells. The goal of this work was to dissect the molecular mechanism by which MAGP2 manipulates Notch signaling. We found that control of Notch by MAGP2 was not dependent on specific Notch receptor‐ligand expression patterns. Interestingly however, we found that mutation of the MAGP2 RGD to a non‐integrin binding RGE caused MAGP2 to promote rather than suppress Notch signaling in endothelial cells. Similarly, soluble integrin blocking RGD peptides and αVβ3 blocking antibodies also increased Notch signaling even in the absence of MAGP2. Further mechanistic dissection revealed that inhibitors of SRC and FAK kinases but not other kinases also increased Notch signaling. Interestingly, in addition to intensifying Notch signaling, RGD peptides and SRC inhibitors also triggered an increase in higher mobility NICD western blot bands and extended NICD half‐life. Our results suggest that these high mobility NICD bands are non‐ubiquitinated forms of NICD fragments. Collectively, we believe these results have revealed a previously undiscovered interaction between integrins and the Notch signaling system that acts to limit Notch signaling via ubiquitination and degradation of active NICD fragments. This novel mechanism may be responsible for ECM control of Notch signaling and angiogenesis.Grant Funding Source: Supported by NIH (NIGMS)
Connexin 37‐mediated growth regulation in primary endothelial cells (LB680)
Authors: Jacobsen Nicole , Burt Janis 
Published: June 2021

We have previously shown that connexin 37 (Cx37) is growth suppressive in vivo, as suggested by increased in ischemia‐induced angiogenesis and collateral vasculogenesis in Cx37‐deficient mice (Am.J.Physiol. 301: H1872‐H1881, 2011). To provide an in vitro system for studies of microvascular capillary growth control mediated by Cx37, we isolated primary skeletal muscle endothelial cells (ECs) from the hindlimb of both wild type (WT) and Cx37‐/‐ mice. Using VE‐cadherin as the positive selection marker and a live cell sorting strategy, we are able to culture primary ECs for 14‐21 days before they lose endothelial character. Evidence for endothelial nature was provided by cell morphology and the continued presence of VE‐cadherin. The growth of ECs was monitored and revealed that proliferation of ECs isolated from WT mice is slowed compared to ECs originating from Cx37‐/‐ mice. Additionally, there is a 4‐day difference between the time it takes to reach confluence of Cx37‐/‐ EC cultures and WT ECs. These data implicate Cx37 in the growth regulation of primary ECs and suggest Cx37 is growth suppressive in microvascular ECs. Future studies will provide further insight into the growth suppression mechanism by Cx37 in primary ECs.Grant Funding Source: Supported by R01HL058732 and T32HL007249