bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Novel Inhibitors of P‐glycoprotein Mediated Multidrug Resistance
Authors: Follit Courtney A. , McCormick James W. , Nanayakkara Amila K. , Wise John G. , Vogel Pia D. 
Published: November 2023

Multidrug resistance (MDR) in cancers due to the overexpression of multidrug transporter proteins such as P‐glycoprotein (P‐gp) is a leading cause of chemotherapy failure. P‐gp uses ATP binding and hydrolysis to export a broad range of structurally dissimilar compounds, including many of the most commonly used chemotherapeutics. While this mechanism helps to protect tissues from toxins, the overexpression of P‐gp presents a major obstacle to cancer pharmacotherapy by preventing chemotherapeutics from reaching effective concentrations in the cancer cells. Reversing MDR by inhibiting P‐gp mediated efflux has been attempted for many years. The search for MDR reversing agents has resulted in a number of hit and lead compounds, many of which competitively inhibited chemotherapeutic transport by P‐gp, but to date none have succeeded in becoming FDA‐approved drugs. By searching for compounds that interact preferentially with the ATP binding domains of P‐gp, instead of the drug binding domain, we aim to identify inhibitors of P‐gp with novel mechanisms of action. We predict that these properties will be more suitable for future development of co‐therapeutics to reverse MDR.In in silico studies using targeted molecular dynamics and massively parallel drug docking of millions of drug‐like molecules, we have identified hundreds of potential inhibitors predicted to have high affinity for the ATP binding domain of P‐gp but low affinity for its drug binding domain. We previously reported that four of these compounds inhibited P‐gp catalyzed ATP hydrolysis (Brewer FK, Follit CA, Vogel PD, Wise JG (2014) Molecular Pharmacology, 86(6), 716–726) and three of those reversed the P‐gp mediated MDR phenotype of prostate cancer cells in culture (Follit CA, Brewer FK, Wise JG, Vogel PD (2015) Pharmacology Research & Perspectives 3(5): e00170). Here, we describe our continued search for potent P‐gp inhibitors using a cell‐based assay for initial screening of predicted P‐gp inhibitors that reports on the metabolic activity of the cells. “Hits” that were found to reverse MDR in a prostate cancer cell line after assaying ~100 computationally identified compounds, were further evaluated by live cell imaging. The majority of inhibitors identified in the metabolic activity assays also demonstrated inhibition of P‐gp‐catalyzed efflux of P‐gp substrates in the cell imaging experiments, supporting the usefulness of the metabolic activity assay as a medium‐throughput primary screen.Support or Funding InformationThis work is supported by NIH NIGMS [R15GM09477102] to JGW/PDV, SMU Dissertation Fellowship, SMU University Research Council, SMU Center for Drug Discovery, Design and Delivery, The Communities Foundation of Texas, and a private gift from Ms. Suzy Ruff of Dallas, Texas.
SENP1 mediated deSUMOylation of KLF15 in Human Pulmonary Microvascular Endothelial Cells: A critical pathway for the development of hypoxic pulmonary hypertension
Authors: Pandey Deepesh , Nomura Yohei , Hori Daijiro , Bhatta Anil , Leucker Thorsten , Shimoda Larissa Akimi , Berkowitz Dan , Romer Lew 
Published: November 2023

RationaleApart from hypoxia inducible factor (HIF), there are very limited studies describing master transcriptional regulators of critical genes important in endothelial dysfunction during hypoxia.ObjectiveKruppel Like Factor 15 has recently been shown to be critical for activation of proinflammatory processes in vascular smooth muscle contributing to atherogenesis. Although KLF15 is abundantly expressed in vascular endothelium the role of KLF15 in the regulation of vascular endothelial function remains poorly understood. Here we tested the hypothesis that KLF15 is a critical regulator of Arg2 transcription in hypoxia exposed human pulmonary microvascular endothelial cells.Approach and ResultsAdenovirally mediated overexpression of KLF15 in human pulmonary microvascular endothelial cells (HPMEC) and in rat pulmonary arteries decreased Arg2 mRNA, protein abundance, and activity. HPMECs exposed to 48 hours of hypoxia exhibited a robust decrease in KLF15 protein levels (that was sustained after 24 hours of reoxygenation) and a reciprocal increase in Arg2 protein and mRNA expression. Chromatin immunoprecipitation (CHIP) indicated direct binding of KLF15 to the Arg2 promoter, which was relieved when HPMEC were exposed to hypoxia, Further, overexpression of KLF15 reversed hypoxia‐induced augmentation of arginase activity and decrements in Nitric Oxide production in HPMEC, and also reversed hypoxia‐induced endothelial dysfunction in isolated rat pulmonary artery rings. Finally, we have elucidated the mechanism by which hypoxia regulates KLF15 abundance/stability and altered cytoplasmic vs. nuclear compartmentalization in HPMEC, a process that involves de‐Sumoylation of KLF15 at lysine 116 residue by SENP1.ConclusionsKLF15 is a critical regulator and repressor of endothelial Arg2 expression, and thereby, NO and pulmonary endothelial function/dysfunction. Overexpression or activation of KLF15 may represent novel therapeutic strategies for pulmonary hypertensionSupport or Funding InformationThis work was supported by American Heart Association Scientist Development Grant to Deepesh Pandey (16SDG27340010), 2017 StAAR award from Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine. NIH‐R01HL124213 to Dan Berkowitz.
Endothelial HIF‐1α Is Required for Endothelial Regeneration and Vascular Repair Following Sepsis Challenge
Authors: Huang Xiaojia , Zhang Xianmin , Zhao Youyang 
Published: November 2023

BackgroundEndothelial repair is critical for the maintenance of vascular homeostasis after inflammatory injury. However, little is known about the intrinsic pathways that trigger endothelial regeneration and inflammation resolution.Methods and ResultsEmploying the mice with Tie2Cre‐mediated disruption of HIF‐1α (encoding hypoxia inducible factor 1, HIF‐1α) (Hif1αTie2) in endothelial cells, we demonstrated that endothelial regeneration requires activation of HIF‐1α signaling in endothelial cells, which subsequently regulates the expression of the reparative transcription factor Forkhead box M1 (FoxM1). Hif1αTie2 mice exhibited impaired vascular repair, persistent lung inflammation, and increased mortality rate after sepsis challenge. Selective restoration of either HIF‐1α or FoxM1 in pulmonary vascular endothelial cells in HIF1αTie2 mice restored endothelial proliferation and reversed the defective vascular repair. Activation of HIF‐1α via a pharmacological approach potentiated endothelial regeneration and vascular repair.ConclusionsThese studies defined a critical role of endothelial HIF‐1α in activating the intrinsic FoxM1‐dependent endothelial regeneration program following inflammatory vascular injury. Thus, activation of HIF‐1α‐mediated endothelial regeneration is a promising strategy for treatment of inflammatory vascular diseases such as acute respiratory distress syndrome.Support or Funding InformationThis work was supported by NIH grants R01HL123957, R01HL125350.
Intestinal epithelial barrier function is disrupted by acrolein, an environmental/dietary pollutant and lipid metabolite
Authors: Chen Wei‐Yang , Zhang Jingwen , Barve Shirish , McClain Craig , Joshi‐Barve Swati 
Published: November 2023

The gastrointestinal epithelial barrier function is critical for maintaining selective gut permeability that limits the entry of bacteria and pathological bacterial components (e.g., endotoxin, lipopolysaccharide‐LPS) into systemic circulation, which can result in inflammation and injury. Clinical and experimental studies suggest that intestinal barrier dysfunction (“leaky gut”) can predispose to or enhance chronic inflammatory intestinal and non‐intestinal disorders, such as diabetes, IBD, alcoholic liver disease and autoimmune diseases, etc. Many environmental and dietary factors are thought to alter intestinal epithelium leading to gut permeability and bacterial translocation. Acrolein is an environmental and dietary pollutant, and a lipid‐derived metabolite. This study evaluates the effects of acrolein on intestinal epithelial barrier function and permeability, both in vitro and in vivo. Our data demonstrate that oral acrolein exposure in mice caused intestinal barrier permeability leading to increased translocation of bacterial endotoxin/lipopolysaccharide into the blood. Also, acrolein adversely affected the barrier integrity of a polarized Caco‐2 monolayer, as demonstrated by a decrease in transepithelial electrical resistance (TEER), with a corresponding increase in barrier permeability to a fluorescent dye (FD‐4). Acrolein exposure resulted in the downregulation and delocalization/redistribution of key tight junction proteins (TJP, e.g., zonula occludens‐1, claudin‐1 and occludin) that critically regulate epithelial paracellular permeability. In addition to TJP alterations, acrolein also caused epithelial cell death by apoptosis, which is known to be a significant mechanism that contributes to intestinal barrier dysfunction and permeability in inflammatory bowel diseases. Overall, we demonstrate that exposure to acrolein has a major impact on the intestinal epithelium that involves (i) decrease/redistribution and discontinuous localization of TJPs, and (ii) epithelial cell apoptosis, thereby resulting in loss of barrier integrity/function and permeability. Our findings highlight the adverse consequences of environmental and dietary pollutants/factors on intestinal barrier dysfunction that may contribute to gut permeability and bacterial translocation.Support or Funding InformationSupported by NIH and Veterans Administration.
Importance of Axial Length in the Detection of Carotid Artery Stiffness Induced by a High Fat Diet
Authors: Abshire Caleb Michael , Reverte‐Ribo Virginia , Rosales‐Martinez Carla , Zimmerman Margaret A , Miller Kristen S , Prieto Minolfa , Lindsey Sarah H 
Published: November 2023

Cardiovascular disease (CVD) is the leading cause of death worldwide and in the United States. Arterial stiffness, characterized by reduced compliance in large conducting arteries, is a major risk factor for CVD. Individuals with cardiometabolic risk factors such as obesity and insulin resistance have stiffer arteries and an increased risk of developing CVD. Recent evidence suggests that ex vivo arterial stiffening can be more fully characterized by performing pressure myography at multiple fixed lengths. Therefore, the aims of this study were to characterize the effect of a high fat diet on murine carotid stiffness using biaxial mechanical phenotyping.At 4 weeks of age, some C57BL/6 male mice were placed the DIO Rodent Purified Diet with 45% Energy from fat (HFD, TestDiet 58V8) while control animals remained on a normal diet. At 39 weeks of age, common carotid arteries were harvested and cannulated for assessment of biaxial mechanical properties using pressure myography. After equilibration and pre‐conditioning, in vivo carotid artery length was estimated by finding the length at which the artery caused minimal change to longitudinal force when subjected to pressures ranging from 70–150 mmHg. Pressure‐diameter and force‐length curves were obtained at the estimated in vivo length as well as 5% above and below the estimated in vivo length. Statistical analysis was performed using 2‐way ANOVA with Graphpad Prism.Baseline diameter of carotid arteries pressurized at 10 mmHg tended to be larger in HFD (388 ± 7 μm, n=5) versus control arteries (360 ± 13 μm, n=4, P=0.08). Pressure‐diameter data obtained at the estimated in vivo length showed a significant interaction between diet and pressure (P<0.001) with the largest differences evident at pressures at and above 70 mmHg (P<0.05). HFD significantly decreased arterial compliance, a measure of the change in diameter at each 10 mmHg pressure step (P<0.05), especially at lower pressures. Finally, arterial distensibility was calculated as the percent change in outer diameter from the original diameter obtained at 10 mmHg. HFD significantly decreased distensibility (P<0.05), with the greatest differences found at pressures above 40 mmHg (P<0.05). Interestingly, the impact of diet on arterial compliance was significantly attenuated when experiments were performed at an axial stretch above or below the estimated in vivo length.These data show a significant impact of HFD on carotid stiffness in male C57BL/6 mice. Of note, this difference was only detected when experimental conditions closely approximated the in vivo state. Additional analysis of this data will determine the impact of HFD and axial length on the force‐length and stress‐strain relationships. In conclusion, our study shows the importance of axial length in the analysis of diet‐induced carotid artery stiffness.
Antihyperuricemic and xanthine oxidase inhibitory activities of the ethanolic extract of Tribulus arabicus and its fractions
Authors: Abu‐Gharbieh Eman , Shehab Naglaa G. 
Published: November 2023

Published data concerning the composition and bioactivity of Tribulus arabicus are very limited. This study aimed to investigate the bioactive contents of the Tribulus arabicus grown in the United Arab Emirates, assess xanthine oxidase inhibitory activities of its ethanolic extract, and fractions; hexane, chloroform and n‐butanol and to evaluate their antihyperuricemic in vivo. LD50 of the ethanolic extract confirmed its safety up to 5g/kg. The ethanolic extract and its fractions were evaluated in vitro for their XO inhibitory activity and the in vivo for anti‐hyperuricemic activity using potassium oxonate‐induced hyperuricemia model in mice. Two different doses (250 and 500 mg/kg) of the ethanolic extract were used and one dose (100 mg/kg) was used for each fraction. Allopurinol was used as a positive control.Tribulus arabicus ethanolic extract together with its hexane and n‐butanol fractions exhibited a significant inhibitory effect on xanthine oxidase activity (IC50 20.4, 12.6 and 15.3 μg/mL respectively), while only a modest reduction in enzymatic activity was noticed with chloroform fraction with IC50 45.8 μg/mL. Furthermore, oral administration of the ethanolic extract at doses of 250 and 500 mg/kg reduced significantly the serum urate levels in oxonate‐induced hyperuricemic mice by 30.1 and 64.6% respectively. Hexane and n‐butanol fractions showed a significant reduction in uric acid levels by 51.7 and 54.1% respectively.Results suggest that the ethanolic extract of Tribulus arabicus and its hexane and n‐butanol fractions might have great potential as a hypouricemic agent. This activity is attributed to the high content of phenolic and triterpenoidal compounds.
Anti‐inflammatory effects of Tibouchina granulosa in experimental model of endometriosis
Authors: Guilhon Carolina Carvalho , Minho Alan , Mattos Romulo , Nasciutti Luiz Eurico , Fernandes Patricia Dias 
Published: November 2023

Tibouchina granulosa is an ornamental tree commonly found in Brazil and some species of the genus are used in popular medicine. Researches from our group have shown that the tea from the leaves present a significant wound healing effect and acute anti‐inflammatory activity. Endometriosis is a debilitating gynecologic disease characterized by the implantation of endometrial tissue in ectopic locations. So far there is no treatment to the pathology itself, most of the women have to go through a hormone therapy or surgery. The aim of this study was to analyze if the ethanol extract (EE) from the leaves of T. granulosa, and ethyl acetate fraction (EAF) could be used as a therapy to treat endometriosis.After implantation and establishment of autologous endometrium onto the peritoneum abdominal wall of Swiss webster female mice (25–35g, n = 8–30), the animals were divided in the following groups: vehicle group that received water (p.o.), EE (30 or 100 mg/kg), EAF (10, 30 or 100 mg/kg) for 15 consecutive days. At last day mice were euthanized, the size of the lesion and the quantification of cytokines in serum and in the tissue were performed and compared among the groups. Statistic was done by ANOVA followed by post‐test of Newman‐Keuls's. Protocols for animal use received the number #ICBDFBC‐015 (COBEA/UFRJ/Brazil).Vehicle‐treated group doubled the ectopic lesion size and the explants from the animals treated with all doses of the EE and EAF have maintained its size (1.75 ± 0.49 to vehicle‐treated group versus 1.00 ± 0.39 and 1.21 ± 0.37 to 30 or 100 mg/kg‐EE treated mice and 1.08 ± 0.33, 0.90 ± 0.35, 1.07 ± 0.41 to 10, 30 or 100 mg/kg‐EAF treated groups, respectively). Levels of tumor necrosis factor‐α (TNF‐α) in serum and in ectopic focus were significantly reduced in the EAF‐treated group (100 mg/kg dose) (229.98 ± 61.5 pg/ml in vehicle‐treated group versus 151.8 ± 54.2 pg/ml in EAF‐treated group and 6,686.9 ± 1,061.3 pg/ml protein in vehicle‐treated group versus 2,469.7 ± 2,223.1 pg/ml protein in EAF‐treated group, respectively). The chemokine monocyte chemoattractant protein‐1 (MCP‐1) levels in explant was significantly inhibited with 30 and 100 mg/kg EAF doses (2,505.6 ± 829.6 pg/ml protein in control group versus 1,294.3 ± 312.7 pg/ml of protein and 593.4 ± 141.9 pg/ml of protein to 30 and 100 mg/kg, respectively).Taken together our data suggest that Tibouchina granulosa extract from leaves and it fraction in ethyl acetate have anti‐inflammatory effects in this experimental model of endometriosis.Support or Funding InformationAcknowledgements: Instituto Vital Brazil (donation of animals), CAPES, CNPq and FAPERJ (financial support).
Poloxamer 188 Decreases Hypoxia/Reoxygenation‐Induced LDH Release from Isolated Cardiomyocytes
Authors: Salzman Michele M. , Hackel Benjamin J. , Bates Frank S. , Bartos Jason A. , Yannopoulos Demetris , Riess Matthias L. 
Published: November 2023

IntroductionEven when the best cardiopulmonary resuscitation (CPR) is delivered, many patients who experience a cardiac arrest die or suffer severe cardiac damage. Reintroduction of blood flow at the start of CPR after systemic ischemia may cause additional injury to the heart beyond that caused by the ischemia itself. Determining the mechanism of action of a compound administered during CPR on the cellular (e.g., cardiomyocyte) dysfunction caused by ischemia/reperfusion (I/R) could improve CPR practices in the future.HypothesisPoloxamer 188 (P188), with its unique hydrophilic/lipophilic chemical properties, protects isolated cardiomyocytes against hypoxia/reoxygenation (H/R; simulated I/R) injury.MethodsIsolated cardiomyocytes (human, HCMs) underwent 3 hours hypoxia (1% O2; serum‐& glucose‐free medium; 37°C) then 2 hours reoxygenation (21% O2; complete medium; 37°C) ± P188 [0.1μM–2mM]. Endpoints were markers of cell proliferation, cell viability (mitochondrial dehydrogenase activity), and cellular injury (lactate dehydrogenase [LDH] release). Statistics: ANOVA and SNK post hoc comparisons, p<0.05 *vs normoxia, † vs vehicle.ResultsThere was significantly decreased cell proliferation (15,300±488 vs *13,396±102 cells/well, n = 6) and viability (0.570±0.039 vs *0.482±0.034 abs/well, n = 6), as well as significantly increased LDH release (0.337±0.054 vs *0.975±0.242 abs/well, n = 6), following H/R compared to cells in control/normoxic conditions. P188 did not attenuate the decreased cell proliferation nor viability caused by H/R, but did significantly decrease LDH release in the H/R conditions (†0.520±0.101 vs 0.975±0.242 abs/well, n = 6), albeit not to control/normoxic levels, at a concentration of 1mM. The other P188 concentrations used (0.1μM, 1μM, and 2mM) did not have a significant effect.ConclusionsP188 (1mM) significantly decreased H/R‐induced LDH release from isolated HCMs, but did not attenuate the decreased cell proliferation and viability caused by H/R. P188 protection of cardiomyocytes may require additional components, such as the preservation of nitric oxide release from P188‐protected cardiac endothelial cells.Support or Funding InformationThis work was supported by NIH grant (RO1 HL095122) and institutional funds.
2‐Methoxyestradiol protect against cardiac hypertrophy induced by abdominal aortic constriction
Authors: Almaayah Zaid H. , El‐Kadi Ayman O.S. 
Published: November 2023

Numerous experimental studies have supported the evidence that 2‐methoxyestradiol (2ME) is a biologically active metabolite and mediates multiple effects on the cardiovascular systems that are largely independent of estrogen receptor. 2ME is a major cytochrome P450 1B1 (CYP1B1) metabolite and has been reported to have a vasoprotective and anti‐inflammatory actions. However, whether 2ME would prevent cardiac hypertrophy induced by abdominal aortic constriction (AAC) has not been investigated yet. Therefore, the overall objectives of the present study are to elucidate the potential anti‐hypertrophic effect of 2ME and to explore the mechanism(s) involved. For this purpose, Sprague–Dawley rats were subjected to either sham or abdominal aortic constriction surgery to induce cardiac hypertrophy and treated with 2ME or vehicle. Thereafter, cardiac hypertrophy parameters were determined using echocardiography whereas, protein expression level and the formation of mid‐chain hydroxyeicosatetraenoic acid (mid‐chain HETEs) were measured using western blot analysis and liquid chromatography‐electron spray ionization‐mass spectrometry, respectively. Our results showed that 2ME significantly inhibited cardiac hypertrophy induced by AAC as evidenced by a decrease in the heart weight to tibial length ratio and left ventricular morphology such as intraventricular septum, left ventricular internal diameter and left ventricular posterior wall. Mechanistically, the protective effect of 2ME against cardiac hypertrophy induced by AAC was mediated through a significant inhibition of CYP1B1 and its associated cardiotoxic metabolites mid‐chain HETEs. Our study provides the first evidence that 2ME prevents cardiac hypertrophy induced by AAC through CYP1B1 and mid‐chain HETEs‐dependent mechanisms.Support or Funding InformationThis work was supported by a grant from the CIHR to A.O.S.E. Z.H.M. is the recipient Izaak Walton Killam and Alberta Innovates‐Health solution Scholarships.