bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sexual dimorphism in aortic endothelial function of Zucker diabetic fatty rats: possible involvement of superoxide production (1051.8)
Authors: Han Xiaoyuan , Shaligram Sonali , Sangüesa Gemma , Anderson Leigh , Rahimian Roshanak 
Published: June 2021

Little is known about the interaction between diabetes and sex in vasculature. This study was designed to investigate whether there were sex differences in rat aortic endothelium‐dependent vasodilation (EDV) in Zucker diabetic fatty (ZDF) rats, and the potential role of superoxide. EDV to acetylcholine (ACh) was measured in aortic rings pre‐contracted with phenylephrine before and after pretreatment with apocynin (100 μM), a NADPH oxidase (Nox) inhibitor. In addition, the level of Nox (a potent source of superoxide) and PKCβ mRNA expression were determined using real‐time RT‐PCR. ACh‐induced relaxations were significantly greater in female lean rats compared with male lean rats. Accordingly, male lean rats had higher PKCβI expression level than female lean rats. Diabetes significantly impaired EDV in aortic rings from female ZDF rats, however, potentiated the relaxation in males. Pre‐incubation of aortic rings with apocynin increased EDV only in diabetic female group, suggesting impairment of EDV in female ZDF aorta was partly due to an increase in the activity of superoxide. Accordingly, the levels of Nox1, Nox4, and PKCβ mRNA expression were substantially enhanced in aorta of female ZDF rats compared to those in lean animals. These data suggest that an elevation of superoxide may partially contribute to the predisposition of the female aorta to injury in type 2 diabetes.Grant Funding Source: NIH/NIDCR
Evidence that chronic administration of 17β‐estradiol decreased the vasopressor responses in streptozotocin‐diabetic female rats (1051.9)
Authors: Centurion David , Acosta‐Cota Selene , Sanchez‐Lopez Araceli 
Published: June 2021

In vitro studies have shown that 17β‐estradiol has beneficial effects in the cardiovascular system by activation of nitric oxide pathway. However, these effects have not been demonstrated in streptozotocin‐induced diabetic rats in the systemic vasculature in vivo. Thus, this study determined the effect of 17β‐estradiol on the vasopressor responses induced by sympathetic stimulation or i.v. injections of noradrenaline, methoxamine and B HT 933 in sham‐operated or ovariectomized, diabetic or non‐diabetic female rats. For this purpose, rats were ovariectomized or sham‐operated. One week later the animals were treated with streptozotocin (60 mg/kg, i.p.) or its vehicle. Two weeks later these rats were treated with 17β‐estradiol (10 μg/kg, s.c.) or its vehicle daily during five weeks. Then, under anaesthesia with ketamine and xylazine, the animals were pithed and prepared to measure blood pressure and heart rate. 17β‐estradiol failed to modify the vasopressor responses to: (i) sympathetic stimulation, noradrenaline, methoxamine or B HT 933 in sham‐operated non‐diabetic rats; (ii) sympathetic stimulation or B‐HT 933 in sham‐ operated diabetic rats; (iii) noradrenaline or methoxamine in ovariectomized non‐diabetic rats. In contrast, 17β‐estradiol significantly decreased the vasopressor responses to: (i) noradrenaline and methoxamine in sham‐operated diabetic rats; (ii) sympathetic stimulation or B‐HT 933 in ovariectomized non‐diabetic rats; and (iii) sympathetic stimulation, noradrenaline, methoxamine or B HT 933 in ovariectomized diabetic rats. These results, taken together, suggest that chronic administration of 17β‐estradiol produced a protective effect in the systemic vasculature in streptozotocin‐induced diabetic rats. This is the first in vivo study showing this protective effect of 17β‐estradiol during diabetes.This project was financially supported by Conacyt (Grant number 152534).Grant Funding Source: Supported by Conacyt 152534
Mitophagy‐mediated NLRP3 inflammasome inhibition by andrographolide contributes to the prevention of colitis‐associated cancer (1052.3)
Authors: Sun Yang , Guo Wenjie , Xu Qiang 
Published: June 2021

Intestinal nonresolving inflammation predisposes to the development of colitis‐associated cancer (CAC). Inflammasomes are believed to mediate intestine homeostasis, and their dysregulation contribute to inflammatory diseases and CAC. However, few agent capable of targeting inflammasomes to reduce CAC has been reported thus far. Here we report that small molecule andrographolide protects mice against CAC in the mouse model of azoxymethane combination of dextran sulfate sodium through inhibiting NLRP3 inflammasome. Oral administration of andrographolide significantly attenuated the colitis progression and tumors burden, which was accompanied by lessened body weight loss, lower disease activity index, decreased expression of cyclooxygenase‐2 and proinflammatory cytokines, lower activation of NF‐κB and STAT3, as well as reduced cell proliferation and angiogenesis in the colons of CAC mice. Further study showed that andrographolide inhibited NLRP3 inflammasome activation in macrophage in vivo and in vitro, as indicated by reduced expression of cleaved CASP1, disruption of NLRP3/PYCARD/CASP1 complex assembly and lower IL‐1β secretion. Moreover, andrographolide was found to trigger mitophagy in macrophage, leading to the less mitochondrial membrane potential collapse, and this in turn inactivated the NLRP3 inflammasome. Furthermore, inhibition of the PIK3CA‐AKT1‐MTOR‐RPS6KB1 pathway accounted for the induction of autophagy by andrographolide. Finally, andrographolide‐induced inhibition of IL‐1β production was blocked by the knockdown of BECN1 expression, or by autophagy inhibitor 3‐methyladenine. Taken together, our findings demonstrate that andrographolide‐driven mitophagy‐mediated NLRP3 inflammasome inhibition is responsible for the prevention of CAC. Our data may help to guide decisions regarding the use of andrographolide in colitis patients, which ultimately reduces the risk of CAC.Grant Funding Source: supported by NSFC of China (Nos. 91229109, 90913023, 81121062, 91129728 and 81273528)
Bioequivalence of alendronate and vitamin D3 in an alendronate/vitamin D3 combination tablet (1053.2)
Authors: Yeh Geng‐Chang , Brown Kevin , Mols Ramon , Woolf Eric , Wright Hamish , Maganti Lata , Zajic Stefan 
Published: June 2021

FOSAMAX® PLUS D is a once‐weekly alendronate (ALN) 70‐mg / vitamin D3 (vit‐D3) 5600 IU combination tablet developed by Merck & Co., Inc. A single‐dose, open‐label, randomized, 2‐period, crossover study was conducted to test bioequivalence between FOSAMAX® PLUS D combination tablets and co‐administration of corresponding doses of ALN 70‐mg (FOSAMAX®) and vit‐D3 5600 IU (2x 2800 IU) as individual tablets in healthy male and female Asian subjects to support registration in Taiwan.Results: the 90%CI of the GMR for ALN AUC0‐∞ fell within the pre‐specified bioequivalence bounds of 0.8 to 1.25, but slightly exceeded 1.25 for ALN AUC0‐last and Cmax. The 90% CI of the GMR for vit‐D3, unadjusted for endogenous vit‐D3, was also contained within the pre‐specified bioequivalence bounds. Thus, the combination tablet was bioequivalent based on ALN AUC0‐∞ and vit‐D3 unadjusted for endogenous levels. However, it was not bioequivalent to co‐administration with respect to ALN AUC0‐last and Cmax .In conclusion, the small differences between the combination tablet and co‐administration of individual doses for ALN AUC0‐last and Cmax are not considered to be clinically significant, as slightly increased ALN concentrations are unlikely to meaningfully affect the safety profile. TFDA accepted these results and considered them supportive for registration of the combination tablet in Taiwan.
New antiplatelet and vasorelaxant agents based on the pyridazinone moiety (1054.6)
Authors: Besada Pedro , Costas Tamara , Costas‐Lago M. Carmen , Vila Noemi , Yañez Matilde , Acevedo Laura , Cano Ernesto , Teran Carmen 
Published: June 2021

The pharmacological profile of pyridazinone derivatives includes interesting properties on cardiovascular system as platelet aggregation inhibition and antihypertensive activity. The presence of a 6‐aryl group in the pyridazinone ring was considered essential for the activity on cardiovascular system through the inhibition of phosphodiesterase III (PDE III). Recently, the removal / replacement of the aryl group at C6 has provided potent antiplatelet analogues whose activity does not rely on PDE III inhibition. Therefore, in the search of new structural modifications on the pyridazinone ring that could provide derivatives with novel mechanisms of action, we have designed and synthesized pyridazinones with a functionalized alkyl chain at C4, C5 and/or C6 as well as N2 substituted. Vasorelaxant activity was tested on noradrenaline treated intact rat aortic rings showing several derivatives moderate activity. The most promise results were obtained in the platelet aggregation studies performed following the Born's turbidimetric method and inducing aggregation with thrombine and collagen. Thus, the majority of the new analogues selectively inhibited aggregation induced by collagen in the µM range, being more potent than aspirinGrant Funding Source: Supported by Xunta de Galicia (CN 2012/184)
Epigenetic regulation of IL‐6 by pro‐inflammatory cytokines in rheumatoid arthritis synovial fibroblasts: role of HDAC inhibitors (1054.8)
Authors: Riegsecker Sharayah , Wingerter Wylie , Singh Anil , Bhansali Pravin , Tillekeratne L. M. Viranga , Ahmed Salahuddin 
Published: June 2021

Histone deacetylase inhibitors (HDACi) have gained significant attention in recent years due to their anti‐rheumatic activity and potential clinical application. However, the exact role of different HDAC classes in rheumatoid arthritis (RA) is not yet defined, which has limited our ability to target HDACs for therapeutic gain. In order to gain some insights on the epigenetic regulation of synovial inflammation and tissue destruction observed in RA, the present study was carried out to evaluate the role of HDACs in cytokine‐induced IL‐6 synthesis by RA synovial fibroblasts (RA‐FLS) and the influence of cytokine combination. Effect of class I HDACi (Largazole, LAR) or pan‐HDACi vorinostat (SAHA) was determined on TNF‐α (20 ng/ml), IFN‐γ (10 ng/ml), or IL‐1β (10 ng/ml)‐induced IL‐6 expression in RA‐FLS by Western blotting and qRT‐PCR. IL‐6 production under different treatment conditions was also compared with IL‐8 production. Results of the study showed that TNF‐α‐induced IL‐6 expression in RA‐FLS was further amplified in the presence of class I HDACi (LAR, 2‐5 μM) or pan‐HDACi (SAHA, 5 μM) (p<0.05). Surprisingly, we also observed that LAR downregulated TNF‐α/IL‐1β‐induced IL‐6 production by ~50%, but further enhanced TNF‐α/ IFN‐γ‐induced IL‐6 production by ~25%. Evaluation of the signaling pathways suggests that LAR effectively cooperated with TNF‐α to induce phosphorylation of AKT, which may partly be the reason for its IL‐6 increasing property in RA‐FLS. Results of the present study suggest that LAR may interact differently with TNF‐α, IL‐1β, and/or IFN‐γ to induce or inhibit IL‐6 production in RA‐FLS. Thus, our study highlights a need for validating the exact role of specific HDAC isoforms in RA pathogenesis before highly selective inhibitors could be designed and tested for the treatment of RA.Grant Funding Source: Supported by NIH/NIAMS grants (AR063104 and AR55741) and University of Toledo Start‐up funds to SA.
Differential modulation of p‐4EBP1, p‐ERK and cyclin D1 by amuvatinib/erlotinib treatment in prostate cancer cells (1055.4)
Authors: Canatsey Ryan , Cai Wesley , Mastrandrea Nicholas , Gard Jaime , Nagle Ray , Monks Terrence , Lau Serrine 
Published: June 2021

Cyclin D1 is a key regulator of cell cycle progression and a therapeutic endpoint for cancer treatment. The human prostate cancer cell lines, LNCaP (PTEN‐) and DU145 (PTEN+), were used to examine the differential regulation of cyclin D1 as a determinant of drug sensitivity to amuvatinib, a receptor tyrosine kinase inhibitor, and erlotinib, an epidermal growth factor inhibitor. 1D and 2D Western blot analysis revealed that combination drug treatment of LNCaP cells caused a decrease in 4EBP1 pSer65, pThr70, and pThr37/46, with concomitant decreases in cyclin D1 levels. Such combination treatment, however, did not modulate pERK status. Moreover, single drug treatment with amuvatinib, but not erlotinib, decreased p‐4EBP1 and cyclin D1 levels. In DU‐145 cells, combination drug treatment had no effect on p‐4EBP1 status, but decreased p‐ERK and cyclin D1 levels. Additionally, single drug treatment with erlotinib, but not amuvatinib, caused a loss of p‐ERK and cyclin D1. The data reveal the differential modulation of cyclin D1, and its upstream regulators, in prostate cancer cell lines by amuvatinib and erlotinib. Such differential responses likely contribute to specific anti‐tumor agent efficacy. An appreciation of factors that determine the cell‐dependent modulation of cyclin D1 will assist in the selection of appropriate biomarkers for directing patient‐targeted therapy.Grant Funding Source: Supported by Ventana/Roche, P30 ES006694
Pentadecapeptide BPC 157 and anaphylactoid reaction in rats and mice after intravenous dextran and white egg administration (1056.7)
Authors: Duplancic Bozidar , Stambolija Vasilije , Katancic Holjevac Jadranka , Zemba Mladen , Balenovic Igor , Drmic Ivan , Suran Jelena , Radic Bozo , Filipovic Marinko , Boban Blagaic Alenka , Brcic Luka , Kolenc Danijela , Seiwerth Sven , Sikiric Predrag , Grabarevic Zeljko 
Published: June 2021

The objective of this study was to evaluate the effect of pentadecapeptide BPC 157 in anaphylactoid reaction in rats and mice after intravenous dextran and white egg administration.Anesthetized mice and rats received intravenously 6%, 10%, 20%, 40%, 60%, 80%, 90% dextran and/or white egg (1ml/rat or 0.15ml/mouse) into their tails. Medication (/kg b.w., 5 ml/kg) was given intraperitoneally (BPC 157 10 µg, 1 µg, 10 ng, 10 pg/kg, chloropyramine 20 mg/kg, cimetidine 10 mg/kg intraperitoneally, alone or in combination while controls received an equivolume of saline), immediately after challenge or, alternatively, at 5 min after or 24 or 48 h before challenge. The effect was assessed at 5, 10, 20 and 30 min after dextran and/or white egg challenge. We commonly noted prominent edema involving the face, upper and lower lip, snout, paws and scrotum (presented with extreme cyanosis), poor respiration and the number of fatalities after dextran and/or white egg application. Contrary, BPC 157 regimens (10 µg, 1 µg, 10 ng, 10 pg/kg) effectively, may both prevent anaphylactoid reactions that may arise from dextran and/or white egg application and furthermore, rescue already advanced reactions when given after the challenge. Chloropyramine and cimetidine given alone were only moderately effective. When given together with BPC 157, the observed effect correlates with the strong effect of BPC 157 given alone.In conclusion, we advocate BPC 157 use in anaphylaxis therapy.Grant Funding Source: Supported by Grant 108‐ 1083570‐3635, Croatia
PSD95 scaffolding of the Shaker‐type K+ channel enables PKA‐dependent phosphorylation and vasodilation of cerebral arteries (1057.7)
Authors: Moore Christopher , Nelson Piper , Parelkar Nikhil , Hanvey Hillary , Rusch Nancy , Rhee Sung 
Published: June 2021

Postsynaptic density‐95 (PSD95) is a membrane‐associated scaffolding protein in rat cerebral vascular smooth muscle cells (cVSMC), which associates with voltage‐gated, Shaker‐type K+ (KV1) channels at the plasma membrane. Here, we used a membrane‐permeable peptide (KV1‐C) that competes with KV1.2 subunits for PSD95 binding to demonstrate the physiologic role of PSD95‐KV1.2 association in cVSMC. Application of 10 µM KV1‐C peptide to pressurized cerebral arteries (CA) induced vasoconstriction (23 ± 2%); the KV1 channel blocker, 5‐(4‐phenylalkoxypsoralen (100 nM psora4), did not further constrict these CA. Vasoconstriction by 1 µM linopirdine or 30 µM BaCl was unaffected by KV1‐C, suggesting that KV1‐C does not interfere with the dilator function of KV7 or KIR channels, respectively. cVSMCs in pressurized CA depolarized by 12 ± 2 mV in response to KV1‐C and psora4‐sensitive K+ current was reduced ~40% by KV1‐C peptide in cVSMCs. CA visualized in cranial windows in vivo also constricted (17 ± 3%) in response to KV1‐C. Finally, Western blots employing a phospho‐PKA substrate antibody revealed markedly less phosphorylation of KV1 channels in CA exposed to KV1‐C, and phosphatase inhibitors partially blunted KV1‐C mediated vasoconstriction. These results suggest that the PSD95 scaffold exerts a basal vasodilator influence in rat CA by enabling the phosphorylation ‐dependent and selective opening of KV1 channels.Grant Funding Source: Supported by NIH R01 HL097107 (SWR) and American Heart Association 13PRE17070035 (CLM)
Comparing the high affinity benzodiazepine binding site with the homologous “CGS 9895” site in GABA‐A receptors (1059.1)
Authors: Puthenkalam Roshan , Varagic Zdravko , Dereky Anna , Suwattanasophon Chonticha , Sarto‐Jackson Isabella , Scholze Petra , Sieghart Werner , Ernst Margot 
Published: June 2021

GABA‐A receptors are the major inhibitory transmitter receptors in the brain and the site of action of many clinically important drugs. CGS 9895 and many other pyrazoloquinolinones are high affinity null modulators at the benzodiazepine (Bz) binding site and at higher concentrations also modulate the receptors via the α+β‐ interface. To gain insights into the interactions of CGS 9895 with both binding sites, we used our homology models to select γ2‐ side amino acid residues important for Bz binding and to incorporate them into the β3‐ side by site directed mutagenesis. These mutated β3 subunits were co‐expressed with α subunits. The recombinant receptors were investigated by the two electrode voltage clamp method in Xenopus laevis oocytes and by radioligand binding assays. With only four mutations we were able to introduce a high affinity binding site for CGS 9895 into αβ3 receptors. Furthermore, GABA currents of several recombinant αβ3(mut) receptors could be modulated by the tested pyrazoloquinolinones and by other ligands of the high affinity Bz binding site, but not by diazepam. We thus introduced a subsite of the high affinity Bz binding site into the α+β3‐ interface.Grant Funding Source: Supported by FWF W1232 Molecular Drug Targets
Modulatory effects of 5‐HT2A and AMPA receptors on in vivo serotonin levels in two key areas of the brain related to depression (1059.12)
Authors: Zhou Zhu , Chan Patrick , Uchizono James 
Published: June 2021

In this work, we explored two in vivo pharmacodynamic targets that alter serotonin (5‐HT): AMPA and 5‐HT2A receptors in the dorsal raphe nucleus (DRN) and prefrontal cortex (PFC). We hypothesized that agonism of PFC 5‐HT2A receptors would modulate DRN 5‐HT levels through DRN AMPA receptors. Two microdialysis probes were surgically placed into the DRN and PFC from which 5‐HT measurements were simultaneously recorded. DOI (5‐HT2A agonist), NBQX (AMPA antagonist) and s‐AMPA (AMPA agonist) were delivered via these probes. Three experimental protocols were tested, each with minimum of 14 time data points (n=3‐5) were obtained: A) baseline control (aCSF); DOI (100μΜ). B) aCSF; DOI (100μΜ) + NBQX (300μΜ); C) aCSF; (s)‐AMPA (10μΜ); (s)‐AMPA (50μΜ); (s)‐AMPA (85μΜ). In Protocol A, 5‐HT levels in the DRN and PFC both increased compare to controls. In Protocol B, DOI (100uM)+NBQX (300uM) showed decreased 5‐HT levels compared to a DOI infusion only (100uM). In Protocol C, as s‐AMPA concentration was increased, 5‐HT levels in DRN simultaneously increased. The results support targeting the PFC 5‐HT2A receptor or the DRN AMPA receptor directly to modulate DRN [5‐HT] for future potential anti‐depressant modalities.Grant Funding Source: Supported by Formurex, Inc.
Regulated ubiquitination and SUMOylation of pregnane X receptor (1062.10)
Authors: Sun Mengxi , Staudinger Jeff 
Published: June 2021

Highly expressed in the entero‐hepatic system, pregnane X receptor (PXR, NR1I2) is a well‐characterized nuclear receptor that regulates the expression of genes encoding key drug metabolizing enzymes and drug transporter proteins. The net effect of PXR activation is to increase metabolism and clearance of drugs and xenobiotics from the body. Activation of PXR also plays a pivotal role in mediating adverse drug‐drug interactions. The complete understanding of PXR biology is thus important for the prevention of adverse drug‐drug interactions and the development of safe and effective therapeutic strategies. Recent research recognizes that post‐translational modification (PTM) of PXR (e.g; phosphorylation, ubiquitination, SUMOylation) significantly impacts its function; however, these studies are still in their infancy. Here we present a novel method of determining the extent to which ubiquitination and SUMOylation of PXR occurs. Our data indicate that PXR is the simultaneous target of the ubiquitin and SUMO signaling pathways, and that these PTMs modulate PXR‐biological activity.Grant Funding Source: Supported by NIH‐090558
4‐Phenylbutyrate protects renal proximal tubular cells from palmitic acid‐induced endoplasmic reticulum stress and cell death (1063.2)
Authors: Munusamy Shankar , Alkhiyami Dania , Berzou Souad , Moeinzadeh Atefeh , Mohamed Hebatalla 
Published: June 2021

Obesity is implicated as a significant risk factor for chronic kidney disease (CKD). High plasma free fatty acid levels observed with obesity impairs the endoplasmic reticulum (ER) and cause ER stress. Chemical chaperones, which relieve ER stress, such as 4‐phenylbutyrate (4‐PBA) have been shown to protect the liver and pancreas against obesity‐induced organ damage; however, their protective role in obesity‐induced renal damage is unknown. Thus, we investigated the nephroprotective role of 4‐PBA in an in vitro model of palmitic acid (PA)‐induced ER stress and renal injury using normal rat kidney cells (NRK‐52E). Cells were divided into four groups: Control, 250 μM PA‐treated, 5 mM 4‐PBA‐treated, and 4‐PBA+PA co‐treated. After 24 h of PA and/or 4‐PBA treatments, cell viability and caspase‐3/7 activity (a marker of apoptosis) were determined. Immunoblot analyses were performed to quantitate the levels of ER stress markers ‐ glucose‐regulated protein (GRP78) and C/EBP homologous protein (CHOP) ‐ in renal cells. Exposure to PA significantly reduced the viability (81.3% to that of control) in NRK‐52E cells, and markedly increased the activity of caspase‐3/7 activity (2‐fold increase over control) and the expression of ER stress markers GRP78 and CHOP (1.6 and 2 folds over control respectively) at P‐value < 0.05. Intriguingly, cells treated with 4‐PBA were protected from PA‐induced ER stress and apoptotic cell death. Our studies demonstrate that 4‐PBA acts as nephroprotectant and prevents fatty acid‐induced ER stress and apoptosis in renal cells. Further investigations in vivo are required to validate the therapeutic potential of 4‐PBA to protect the kidney and prevent the development of CKD during obesity.Grant Funding Source: Supported by Qatar Univ. Student Research Grants # QUST‐CPH‐FALL‐12/13‐6 and QUST‐CPH‐SPR‐12/13‐3.