bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comprehensive characterization of mouse hepatic UDP‐glucuronosyltransferases: Major participation of Ugt2b1 in bisphenol A glucuronidation
Authors: Ishii Yuji , Yamashita Ryohei , Kurita Ayumi , Miyauchi Yuu , Ikushiro Shin'ichi , Mackenzie Peter I , Tanaka Yoshitaka 
Published: June 2021

PurposeBisphenol A (BPA), which exhibits estrogen‐like properties, is a starting material for the synthesis of plastic especially for polycarbonates. The endocrine disruption due to the contamination of BPA in the baby bottle has been of much concern. The mouse has been regarded as an important animal for endocrinological and toxicological studies. Although UGT2B1 is known as one of the catalysts in rat liver, the isoforms participating in BPA glucuronidation in mouse have not yet been identified. To address this issue, we comprehensively characterized all the Ugt isoforms in mouse liver for BPA glucuronidation.MethodscDNAs of all the Ugt isoforms in mouse liver were amplified from total RNA of FVB mouse liver and cloned into pFastBac1. A baculovirus‐Sf9 cell system for expressing each Ugt isoform was established. The activity of microsomes expressing recombinant mouse Ugt was determined using the substrate BPA by ultra performance liquid chromatography with UV detection.Results and DiscussionOn the basis of the kinetic parameters of BPA glucuronidation by mouse liver microsomes, substrate concentrations were set at 100 μM (near Km) and 400 μM, which is expected to give Vmax. Of all the Ugt mouse‐liver isoforms examined, Ugt2b1 had the highest activity toward BPA at 100 μM while much lower activities were observed with Ugt2b34, Ugt1a9, and Ugt1a6b. Furthermore, Ugt2b1 consistently exhibited high activity toward BPA at 400 μM whereas the activity of Ugt2b34, Ugt1a9 and Ugt1a6b was lowered at this high concentration. The other isoforms exhibited little activity toward BPA at 100 μM and 400 μM.ConclusionsThese results suggest that Ugt2b1 is the major contributor to BPA glucuronidation in mouse liver. To address the glucuronidation of BPA at the level which causes endocrine disruption, the major participation of Ugt2b1 followed by Ugt2b34, Ugt1a9 and Ugt1a6b should be considered.Support or Funding InformationJSPS KAKENHI Grant Number JP17H00788This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
In Vitro Approach to Addressing Violative Drug Residues in Cattle
Authors: Bartholomay Kathryn A , Shappell Nancy W 
Published: June 2021

Violative residues of the veterinary drug flunixin (FNX) are sometimes found in cattle that were presumably slaughtered in accordance with the withdrawal period prescribed by federal guidelines. A possible cause for violative residues may be slow rates of FNX metabolism associated with sex, age or illness of animals. Experiments were designed to investigate the effects of sex and age on rates of flunixin metabolism using liver microsomal, S9, cytosol, and homogenate fractions from heifers (n=5) and steers (n=6) less than 30 months of age, and cows (n=8) older than 48 months of age. Validation of subcellular fractions was achieved through enzyme analyses: cytochrome P450 (P450), NADPH‐P450 reductase and glucose‐6‐phosphate dehydrogenase (G6PDH) activities under optimized conditions. Similarly, conditions for flunixin metabolism were optimized and fractional activity and metabolite formation was determined. Cows had lower (P < 0.05) concentrations of P450, NADPH‐P450 reductase activity, and FNX metabolism than their younger counterparts (heifers or steers). Using 15 min incubations, 5‐hydroxy FNX was the major metabolite detected by LC MS‐MS. Variables including exact animal age, cattle breed, diet, health and physiological status of animals at slaughter could have influenced results but were not assessed because of limitations associated with tissue collection.Support or Funding InformationAll funding of work was provided by USDA‐ARS.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Angiotensin II induces Cox 2 expression in rat astrocytes via the Angiotensin type 1 receptor
Authors: O'Connor Ann Tenneil , Clark Michelle A 
Published: June 2021

ObjectiveTo determine the effect of Angiotensin II on cyclooxygenase 2 expression in rat astrocytes.BackgroundWe previously showed that Angiotensin (Ang) II mediated pro‐inflammatory and mitogenic actions in astrocytes, and there is growing evidence that neuroinflammation may contribute to sympathoexcitation and hypertension. Further, Cox 1 derived prostanoids were implicated in Ang II‐dependent hypertension. Our goal is to investigate the role of cyclooxygenase 2 (Cox 2) and its metabolites in Ang II‐mediated neuroinflammatory actions in astrocytes. Cox 2 is an enzyme responsible for the synthesis of prostanoids. Prostanoids have both physiological and pathological roles, and contribute to oxidative stress. Thus, Cox 2 may have pro‐ or anti‐inflammatory actions depending on the prostanoids that are produced. Here, we investigated the effect of Ang II on Cox 2 expression in astrocytes isolated from rat brainstem and cerebellum and determined whether any differences in Cox 2 protein levels exist in Wistar (Wis) compared to (SHRs).MethodsBrainstem and cerebellum astrocytes were prepared from 2–3 days Wis and SHR rat pups. These brain areas express RAS components. Quiescent cells were treated with 100nM Ang II for 1 to 48hrs and Ang II receptor inhibitors for 4hrs. We determined Cox 2 protein levels by western blotting.ResultsAng II increased Cox 2 protein levels relative to untreated controls in a time‐dependent manner, in brainstem and cerebellum for both Wis and SHRs. Increases in Cox 2 expression were evident within one hour, with a gradual decrease to almost basal levels by 48hrs. There were significant differences in Ang II‐induced Cox 2 protein levels between Wis and SHRs in brainstem astrocytes. There were no significant differences in Ang II‐induced Cox 2 protein levels between Wis and SHRs in cerebellum astrocytes. Ang II‐induced Cox 2 protein expression in Wis brainstem astrocytes was significantly different from all other samples. These Ang II actions were mediated by the Angiotensin type I receptor (AT1R).ConclusionWe demonstrated that Ang II induced Cox 2 protein expression in astrocytes. Greater elevation of Cox 2 in Wis brainstem could be attributed to the higher expression of AT1R in brainstem compared to the cerebellum. The brainstem regulates autonomic cardiovascular functions. The upstream signaling pathways and the consequences of Cox 2 elevation in rat astrocytes will be the focus of further studies.Support or Funding InformationPresident's Faculty Research and Development Grant, Nova Southeastern UniversityThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A Possible Role of Perivascular Adipocyte Stress in Cardiovascular Dysfunction Prior to the Onset of Diabetes
Authors: Rafeh Rim Wassim , Mroueh Ali , Eid Ali , El‐Yazbi Ahmed F. 
Published: June 2021

Cardiovascular disease is the leading cause of morbidity and mortality among diabetic patients. Although prolonged exposure to hyperglycemia is implicated in the pathogenesis of cardiovascular dysfunction, a significant proportion of patients show established diabetic microvascular complications at initial diagnosis of diabetes, before overt hyperglycemia. Moreover, recent studies from our laboratory have shown that cardiovascular dysfunction is evident in animal models of metabolic challenge before the onset of hyperglycemia and diabetes, thus placing the etiology of this early cardiovascular dysfunction in question. Given the role of adipose tissue inflammation in the pathophysiology of metabolic syndrome, we hypothesized that interactions between perivascular adipose tissue and vascular smooth muscle cells may play a role in early cardiovascular dysfunction. To test this hypothesis, 3T3‐L1 cells were differentiated to adipocyte‐like cells and treated with 1600 μM free fatty acids and 40 mIU/L insulin, mimicking the levels of these mediators in the plasma of rats challenged with 12 weeks of hyper‐caloric diet feeding. The conditioned medium from these cells was used to treat rat aortic vascular smooth muscle cells (VSMC). VSMC metabolic activity and expression of contractile phenotype markers were assessed. A decrease in metabolic activity in MTS assays was observed in cells treated with conditioned media from challenged 3T3 cells compared to those exposed to control media containing the same levels of fatty acids and/or insulin and to those exposed to conditioned media from control 3T3‐L1 cells. This was paralleled with a significant decrease in alpha‐smooth muscle actin in cells treated with conditioned media from stressed 3T3‐L1 cells. Significantly, media with high free fatty acids and/or insulin did not have a direct effect on VSMCs, supporting the idea that metabolic dysfunction‐evoked vascular impairment was induced by adipose tissue inflammation and suggesting the potential involvement of a soluble adipose tissue mediator triggered by the early insult on adipocytes. Furthermore, adipocyte‐differentiated human bone marrow mesenchymal stem cells challenged with the same concentrations of free fatty acids and insulin recruited a greater number of THP‐1 monocytes compared to cells exposed to control medium, suggesting an upregulation of monocyte attractant properties of stressed adipocytes consistent with an inflammatory phenotype. Our preliminary results indicate a possible mechanistic framework whereby metabolic challenge may mediate early VSMC dysfunction prior to overt hyperglycemia.Support or Funding InformationSupported by AUB MPP fund #320148.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Metabolic Stress‐Induced Renal Endothelial Dysfunction
Authors: Hammoud Safaa H. , Mougharbil Nahed , Eid Assaad A. , El‐Yazbi Ahmed F. 
Published: June 2021

The burden of metabolic syndrome (MetS) is increasing globally. MetS has been shown to increase the risk for developing cardiovascular diseases, diabetes and mortality. As such, our group previously reported that perivascular adipose tissue inflammation was associated with cardiac autonomic, aortic contractile and aortic endothelial dysfunction. MetS has been also associated with high levels of kidney disease markers including glomerular filtration rate, proteinuria, and microalbuminuria. In this study, we investigated the impact of MetS on the renal endothelial function in rats fed with high caloric diet for 4, 8, and 12 weeks. Following the planned duration of high caloric intake, kidneys were isolated and perfused with physiological solution containing L‐NAME (NOS inhibitor) and diclofenac (cyclooxygenase inhibitor), and preconstricted with phenylephrine. Endothelial function was assessed as the reduction in vasodilation in response carbachol (CCh). In control rats, nitric oxide (NO) and prostaglandins were found to be the major mediators of the endothelial vasodilatory effect. On the other hand, gradual alteration in renal endothelial function was detected as the duration of the HC feeding was increased. Compared to control values, kidneys obtained from rats with HC intake showed significant increases in CCh‐induced vasodilation. Moreover, prostaglandin vasodilatory function was abolished at 8 weeks followed by loss of NO activity at 12 weeks. Additionally, the residual CCh‐induced relaxation following L‐NAME and diclofenac infusion was no longer concentration dependent, suggesting an upregulation of a poorly controlled compensatory mechanism. Studies were extended to investigate further renal changes in this rat model. HC feeding led to increased glomerular oxidative stress, mesangial expansion and glomerulosclerosis. Together, these results suggest that increasing caloric intake initiate an early progressive renal damage that could be linked to adipose inflammation.Support or Funding InformationResearch support: AUB‐FM grant #320148.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Nicotine Dose Dependently Uncovers Endotoxic Cardiovascular Manifestations of Hypotension and Autonomic Dysfunction in Female Rats
Authors: El‐Lakany Mohammed A , Fouda Mohamed A , El‐Gowelli Hanan M , El‐Mas Mahmoud M 
Published: June 2021

The inflammatory and cardiovascular effects of endotoxemia are dampened down in the female gender due possibly to the immune boosting actions of female sex steroids. Considering that tobacco constituents including nicotine inhibit estrogen synthesis, we tested the hypothesis that nicotine exposure unveils cardiovascular anomalies of endotoxemia in conscious female rats. Hemodynamic and cardiac autonomic profiles were assessed in female rats treated with i.v. lipopolysaccharide (LPS, 10 mg/kg) in the absence and presence of nicotine. Cardiac autonomic function was assessed via time‐ and frequency‐domain analyses of heart rate variability (HRV). In contrast to no effects for i.v. LPS in female rats when used alone over a period of 3 hr, significant and dose‐related decreases and increases in blood pressure (BP) and heart rate (HR), respectively, were seen in rats when nicotine (25, 50, or 100 μg/kg i.v.) was co‐administered with LPS. Signs of cardiac autonomic dysfunction appeared in LPS/nicotine‐treated rats such as decreased time‐domain indices of HRV indices including the standard deviation of beat‐to‐beat intervals (SDRR) and the root mean square of successive beat‐to‐beat differences in R‐R interval durations (rMSSD). Additionally, spectral analysis revealed that the LPS/nicotine regimen (i) reduced the total power of the frequency spectrum, (ii) caused distinct changes in the R‐R oscillations in low‐frequency (LF, increases) and high‐frequency (HF, decreases) ranges, and (iii) shifted the cardiac sympathovagal balance toward sympathetic dominance as indicated by the increases in LF/HF ratios. The reflex autonomic control does not appear to contribute to the nicotine effects because baroreflex dysfunction induced by LPS was preserved after nicotine treatment. Serum estrogen, but not progesterone, levels were reduced by nicotine in a dose‐dependent manner. Together, the data suggest that nicotine acts apparently via reducing estrogen availability to expose the hypotensive and autonomic dysregulating actions of LPS in the female population.Support or Funding InformationSupported by the Science and Technology Development Fund, Egypt (STDF Grant No. 14895)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Monitoring GPCR Induced Atypical MAPK p38 Signaling to Identify Key Regulators of Vascular Inflammation
Authors: Grimsey Neil J 
Published: June 2021

Activation of the mitogen activated protein kinase (MAPK) p38 is a critical regulatory step in pro‐inflammatory signaling and a key target for therapeutic intervention in vascular diseases, including chronic inflammation and lung disease. Our recent studies defined a conserved ubiquitin driven pathway that regulates atypical p38 signaling by a subset of G protein‐coupled receptors (GPCR). Atypical p38 signaling is initiated by GPCR induced c‐Src phosphorylation of an autoinhibitory peptide in the E3 ubiquitin ligase NEDD4‐2. In turn, phospho‐activation releases the autoinhibitory peptide from the catalytic site of NEDD4‐2, a step which is critical for stress induced GPCR ubiquitination and amplification of atypical p38 signaling and inflammation in the vasculature. Despite the critical role of GPCR induced p38 signaling in the onset and progression of many pathophysiological responses, atypical p38 signaling is still relatively understudied. Here we report the development of Försters Resonance Energy Transfer (FRET) biosensors to map the spatiotemporal activation of p38 signaling by multiple GPCRs in vascular endothelial cells. These FRET sensors create an ideal platform for a small‐scale screening pipeline to identify molecular modulators of the atypical p38 signaling pathway. Our studies have already identified multiple regulatory proteins that block the induction and/or magnitude of GPCR induced p38 signaling, perturbing pro‐inflammatory signaling in the vasculature.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Angiotensin‐III induces Interleukin‐6 secretion in vascular smooth muscle cells isolated from SHR and Wistar rats
Authors: ALANAZI AHMED Z , CLARK MICHELLE A. 
Published: June 2021

Interleukin‐6 (IL‐6) is a pleiotropic cytokine with several biological functions such as inflammatory effects, proliferation and differentiation of B lymphocytes, T‐cell activation, and apoptotic function. Angiotensin (Ang) II induce IL‐6 secretion in cultured astrocytes and the effect of Ang III to induce IL‐6 production in vascular smooth muscle cells (VSMCs) has not been described yet. In this present study, we investigated in VSMCs of Wistar rats and spontaneously hypertensive rats (SHRs), the effect of Ang III in induction the secretion of IL‐6. Interestingly, in Wistar VSMCs, Ang II and III were significantly induced IL‐6 secretion in the time dependent manner. However, the IL‐6 secretion mediated by Ang II and III was significantly greater in VSMCs of SHRs. In the hypertensive state, they have similar time effect in stimulation of the IL‐6 production. Ang III promoted IL‐6 secretion via the action on AT1 receptors, as losartan (AT1 receptor antagonist) blocked this effect. AG490 (JAK2) completely diminished IL‐6 secretion induced by Ang III, so JAK2 importance could not be overlook in IL‐6 secretion. Overall, the findings elucidate the pro‐inflammatory effect of Ang III in VSMCs through stimulation of IL‐6 secretion and activation of AT1 receptors.Support or Funding InformationThe Saudi Arabian Cultural Mission (SACM)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Prolonged Exposure of Rats to Bacterial Lipopolysaccharide Accelerates Mortality and blunts Hemodynamic and Renal Effects of Endotoxemia in Sex‐Specific Fashions
Authors: Wedn Abdalla M , El‐Gowilly Sahar M , El‐Mas Mahmoud M 
Published: June 2021

Although the biological effects of endotoxemia have been the subject of extensive investigation, widely different exposure times to endotoxic insults have been employed in reported studies. The current study is an attempt to systematically evaluate the effect of the duration of the endotoxic offence and rat sex on survivability and cardiovascular and renal functions. Rats were injected with i.p. lipopolysaccharide (LPS) once (5 mg/kg) or twice (5 mg/kg/day for 2 consecutive days). Systolic blood pressure (SBP), serum urea and creatinine, renal iNOS expression and responsiveness of isolated perfused kidneys to cumulative bolus injections of acetylcholine (ACh, 0.01–7.29 nmol) or N‐ethylcarboxamidoadenosine (NECA, adenosine analogue, 1.6–100 nmol) were evaluated after 6 hr of the first LPS injection or 1, 2, or 6 days later. Compared with control rats, a single 6‐hr challenge with LPS reduced SBP and renal vasodilatory responses to NECA, but not ACh, and elevated serum urea and creatinine and renal iNOS expression. These effects were sex independent as they were demonstrated in rat sexes. Except for LPS hypotension in male rats, these parameters were restored to near‐control levels 1 day after the septic insult. After 2‐day LPS (i) serum markers of renal function and renal iNOS expression remained unchanged in both rat sexes, (ii) ACh and NECA renal vasodilations were increased in male, but not female, preparations, and (ii) falls in SBP were observed irrespective of rat sex. All hemodynamic or renal parameters were normalized when measured 6 days after endotoxic insult in both male and female rats. Alternatively, the rat mortality was progressively increased over the 6‐day of the study, with this effect being more apparent in male compared with female rats. Our data suggest that the duration of LPS exposure, rat sex, and specific biologic activity are important determinant of the magnitude and direction of the biological effects of endotoxemia.Support or Funding InformationSupported by the Science and Technology Development Fund, Egypt (STDF Grant No. 14895)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differential Regulation of β‐cell Function by Tonically‐active and Receptor‐activated Gαz: Implications for β‐cell Compensation and Failure
Authors: Schaid Michael D , Harrington Jeff , Kelly Grant , Carbajal Kathyrn , Kimple Michelle 
Published: June 2021

Adenylate cyclase(AC) synthesizes the second messenger molecule, cyclic adenosine monophosphate (cAMP). In the insulin‐secreting β‐cell of the pancreatic islet, cAMP has critical roles in glucose‐stimulated insulin secretion and β‐cell replication. The G protein α‐subunit, Gαz, has partial tonic inhibitory activity towards AC. Our previous work has confirmed Gαz‐null mice secrete more insulin and are resistant to glucose intolerance via a significant increase in b‐cell mass. Gαz an also be activated by E‐prostanoid receptor 3 (EP3), a GPCR for the arachidonic acid metabolite, PGE2. Islets from diabetic mice and humans produce more PGE2 and express more EP3 than those from WT controls, while a EP3 antagonist restores insulin secretion. To determine the mechanisms behind the negative regulation of b‐cell function and replication by Gaz, we developed a β‐cell‐specific, cAMP biosensor expressed in intact islets, confirming, for the first time, an inverse relationship between β‐cell cAMP and Ca2+ oscillations. Loss of Gαz has the expected effects on basal β‐cell cAMP levels, and in response to an agonist of the cAMP‐stimulatory glucagon‐like peptide 1 (GLP‐1) receptor. Consistent with a lack of EP3 expression in islets from lean mice, neither agonists nor antagonists of the EP3 receptor have any effects on β‐cell cAMP, Ca2+, or the coordination between the two, regardless of Gαz expression. C57BL/6J Lepob(B6‐Ob) mice are a model of β‐cell compensation. We have shown the EP3:Gαz pathway is up‐regulated in B6‐Ob islets; raising the question as to whether up‐regulation of the this pathway is dysfunctional or beneficial. Here, we confirm B6‐Ob cAMP production and Ca2+ oscillations are up‐regulated as compared to WT mice. In addition, the anti‐phase relationship between cAMP and Ca2+ is lost as a result of reduce phosphodiesterase 1A expression. These results are also consistent with saturation of Ca2+‐regulatable AC isozymes. The EP3 agonist, sulprostone, had no effect on cAMP levels, but blocked Ca2+ influx, suggesting divergent signaling mechanisms between tonically‐active Gαz and receptor‐activated Gαz. The ability of activated Gαz to bind to Rap1GAP, sequestering it from AC, yields a hypothesis for this signaling divergence. Our current model is that cAMP signaling up‐regulated in the compensating β‐cell, ensures Rap1GAP is inactive towards Rap1, allowing Rap1 to promote cAMP‐mediated effects on exocytosis and β‐cell replication while serving as a sink for activated Gαz, inhibiting its action on AC isoforms critical for β‐cell function and mass.Support or Funding InformationI01 BX003700‐01A1, VA BLR&D; R01 DK102598, NIH/NIDDK; and ADA Innovative Basic Science Award 1‐14‐BS‐115This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.