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Background: Chronic stress is associated with activation of the HPA axis, elevation in pro‐inflammatory cytokines, decrease in intestinal epithelial cell tight junction (TJ) proteins, and enhanced visceral pain. It is unknown whether epigenetic regulatory pathways play a role in chronic stress–induced intestinal barrier dysfunction and visceral hyperalgesia. Methods: Young adult male rats were subjected to water avoidance stress ± H3K9 methylation inhibitors or siRNAs. Visceral pain response was assessed. Differentiated Caco‐2/BBE cells and human colonoids were treated with cortisol or IL‐6 ± antagonists. Expression of TJ, IL‐6, and H3K9 methylation status at gene promoters was measured. Transepithelial electrical resistance and FITC‐dextran permeability were evaluated. Key Results: Chronic stress induced IL‐6 up‐regulation prior to a decrease in TJ proteins in the rat colon. The IL‐6 level inversely correlated with occludin expression. Treatment with IL‐6 decreased occludin and induced visceral hyperalgesia. Chronic stress and IL‐6 increased H3K9 methylation and decreased transcriptional GR binding to the occludin gene promoter, leading to down‐regulation of protein expression and increase in paracellular permeability. Intrarectal administration of a H3K9 methylation antagonist prevented chronic stress–induced visceral hyperalgesia in the rat. In a human colonoid model, cortisol decreased occludin expression, which was prevented by the GR antagonist RU486, and IL‐6 increased H3K9 methylation and decreased TJ protein levels, which were prevented by inhibitors of H3K9 methylation. Conclusions & Inferences: Our findings support a novel role for methylation of the repressive histone H3K9 to regulate chronic stress, pro‐inflammatory cytokine–mediated reduction in colon TJ protein levels, and increase in paracellular permeability and visceral hyperalgesia. [ABSTRACT FROM AUTHOR]

Colon crypts are recognized as a mechanical and biochemical Turing patterning model. Colon epithelial Caco‐2 cell monolayer demonstrated 2D Turing patterns via force analysis of apical tight junction live cell imaging which illuminated actomyosin meshwork linking the actomyosin network of individual cells. Actomyosin forces act in a mechanobiological manner that alters cell/nucleus/tissue morphology. We observed the rotational motion of the nucleus in Caco‐2 cells that appears to be driven by actomyosin during the formation of a differentiated confluent epithelium. Single‐ to multi‐cell ring/torus‐shaped genomes were observed prior to complex fractal Turing patterns extending from a rotating torus centre in a spiral pattern consistent with a gene morphogen motif. These features may contribute to the well‐described differentiation from stem cells at the crypt base to the luminal colon epithelium along the crypt axis. This observation may be useful to study the role of mechanogenomic processes and the underlying molecular mechanisms as determinants of cellular and tissue architecture in space and time, which is the focal point of the 4D nucleome initiative. Mathematical and bioengineer modelling of gene circuits and cell shapes may provide a powerful algorithm that will contribute to future precision medicine relevant to a number of common medical disorders. [ABSTRACT FROM AUTHOR]

The effect of three major influence process parameters, carbon addition ratio, ore particle size, and coal particle size on the compressive strength of high-alumina iron ore-coal composite hot briquette (Al-CCB) with the application of response surface methodology is investigated in this paper. The results show that, with using multiple regression analysis, the experimental data can be fitted into a quadratic polynomial model. Based on the coefficient of determination ( R2 = 0.9883) and the analysis of variance (ANOVA), the model shows good agreement with the experimental data. The effect on the compressive strength of Al-CCB from big to small is carbon addition ratio, ore particle size, and coal particle size. In order to obtain the Al-CCB with 600 N of compressive strength, the optimal experiment conditions are found to be the coal addition ratio of 16.44%, ore particle size of −100 mesh and coal particle size of −100 mesh, resulting in an actual compressive strength of 613 N, as compared to the model prediction of 600 N. This paper can provide guidance for the optimization on preparation of Al-CCB. Also, it can offer reference for the process improvement of other ore-coal composite agglomerates. [ABSTRACT FROM AUTHOR]

Long noncoding RNA SPRY4‐IT1 has been reported to promote melanoma cell growth and invasion, and to block apoptosis. The purpose of this study was to investigate the clinical significance of SPRY4‐IT1 in patients with malignant melanoma. The relative expression levels of SPRY4‐IT1 were measured in plasma samples from 70 patients and 79 healthy controls by quantitative reverse transcriptase polymerase chain reaction. SPRY4‐IT1 expression is high in melanoma patients but low in healthy controls, and is closely associated with tumor site and tumor stage. Elevated SPRY4‐IT1 significantly reduces overall survival rates of patients and is considered as an independent prognostic factor in patients with melanoma. The prognostic nomogram shows a good prediction of the probability of 5‐year overall survival of patients with melanoma (c‐index: 0.72). The calibration curve for the probability of survival presents good agreement between actual outcomes and predictive consequences. In summary, SPRY4‐IT1 may be a potential prognostic marker and a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Background and Purpose: Cryptotanshinone (CTS) is a major bioactive diterpenoid isolated from Danshen, an eminent medicinal herb that is used to treat cardiovascular disorders in Asian medicine. However, it is not known whether CTS can prevent experimental atherosclerosis. The present study was designed to investigate the protective effects of CTS on atherosclerosis and its molecular mechanisms of action.Experimental Approach: Apolipoprotein E-deficient (ApoE(-/-)) mice, fed an atherogenic diet, were dosed daily with CTS (15, 45 mg kg(-1) day(-1)) by oral gavage. In vitro studies were carried out in oxidized LDL (oxLDL)-stimulated HUVECs treated with or without CTS.Key Results: CTS significantly attenuated atherosclerotic plaque formation and enhanced plaque stability in ApoE(-/-) mice by inhibiting the expression of lectin-like oxLDL receptor-1 (LOX-1) and MMP-9, as well as inhibiting reactive oxygen species (ROS) generation and NF-κB activation. CTS treatment significantly decreased the levels of serum pro-inflammatory mediators without altering the serum lipid profile. In vitro, CTS decreased oxLDL-induced LOX-1 mRNA and protein expression and, thereby, inhibited LOX-1-mediated adhesion of monocytes to HUVECs, by reducing the expression of adhesion molecules (intracellular adhesion molecule 1 and vascular cellular adhesion molecule 1). Furthermore, CTS inhibited NADPH oxidase subunit 4 (NOX4)-mediated ROS generation and consequent activation of NF-κB in HUVECs.Conclusions and Implications: CTS was shown to have anti-atherosclerotic activity, which was mediated through inhibition of the LOX-1-mediated signalling pathway. This suggests that CTS is a vasculoprotective drug that has potential therapeutic value for the clinical treatment of atherosclerotic cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Coxsackievirus B3 (CVB3), an important human causative pathogen for viral myocarditis, pancreatitis, and meningitis, has evolved different strategies to manipulate the host signaling machinery to ensure successful viral infection. We previously revealed a crucial role for the ERK1/2 signaling pathway in regulating viral infectivity. However, the detail mechanism remains largely unknown. Grb2-associated binder 1 (GAB1) is an important docking protein responsible for intracellular signaling assembly and transduction. In this study, we demonstrated that GAB1 was proteolytically cleaved after CVB3 infection at G175 and G436 by virus-encoded protease 2Apro, independent of caspase activation. Knockdown of GAB1 resulted in a significant reduction of viral protein expression and virus titers. Moreover, we showed that virus-induced cleavage of GAB1 is beneficial to viral growth as the N-terminal proteolytic product of GAB1 (GAB1-N1-174) further enhances ERK1/2 activation and promotes viral replication. Our results collectively suggest that CVB3 targets host GAB1 to generate a GAB1-N1-174 fragment that enhances viral infectivity, at least in part, via activation of the ERK pathway. The findings in this study suggest a novel mechanism that CVB3 employs to subvert the host signaling and facilitate consequent viral replication. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish a quantitative method to evaluate the biotransportation of a drug across the cell membrane. Through the application of the law of mass conservation, the drug transportation rate was calculated based on Fick's law of passive diffusion and the Michaelis-Menten equation. The overall membrane-transportation rate was the sum of the passive diffusion rate and the carrier-mediated diffusion rate, which were calculated as the transportation mass divided by the respective rate. The active ingredients of Puerariae lobatae Radix and Chuanxiong rhizoma, namely, puerarin and ferulic acid, respectively, were used as two model drugs. The transportation rates of puerarin and ferulic acid were obtained by fitting a model that includes both Fick's law of diffusion and the Michaelis-Menten equation. Compared with the overall transportation, the carrier-mediated transport and passive diffusion of 1.59 mmol/L puerarin were -35.07% and 64.93%, respectively, whereas the respective transportation modes of 0.1 mmol/L ferulic acid were -35.40% and 64.60%, respectively. Verapamil and MK-571 increased the overall transport rate and ratio, and MK-571 treatment changed the carrier-mediated transport from negative to positive. However, the transport rate and ratio of ferulic acid did not change significantly. The cell transportation mechanisms of puerarin and ferulic acid primarily involve simple passive diffusion and carrier-mediated transportation. Moreover, P-glycoprotein and multidrug resistance-associated protein efflux proteins, and other transportation proteins were found to be involved in the transportation of puerarin. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Radix Angelicae Dahuricae is the dried root of Angelicae Dahurica (Fisch.ex Hoffm.)Benth.et Hook.f. var. formosana (Boiss.) Shan et Yuan (Fam.Umbelliferae). The total coumarins (Cou) and volatile oil (VO) were main active components that drived from Radix Angelicae Dahuricae. Our previous studies have shown that Cou and VO could increase intestinal absorption for transmucosal drug delivery with unknown mechanism. The aim of this study was to investigate the molecular mechanism of Radix Angelicae Dahuricae for improving drug intestinal transport. Caco-2 cell model was used to study the effect of Radix Angelicae Dahurica on transepithelial electrical resistance. Western blot was used to study its effect on the expression of the actin and ZO-1, tight junction proteins. The effect of Radix Angelicae Dahurica on the expression of P-gp protein was investigated using flow cytometry. VO (0.036-2.88 μL/mL) and Cou (0.027-0.54 mg/mL) caused a reversible, time- and dose-dependent decrease in transepithelial electrical resistance. VO and/or Cou could inhibit the expression of the tight junction protein, ZO-1 and actin. VO and/or Cou also could inhibit the expression of P-gp. These data suggested that Radix Angelicae Dahurica increased cell permeability by affecting the expression of actin, ZO-1 or P-gp, opening the tight junction or inhibiting the efflux induced by P-gp. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Chronic psychological stress is associated with increased intestinal epithelial permeability and visceral hyperalgesia. Lubiprostone, an agonist for chloride channel‐2, promotes secretion and accelerates restoration of injury‐induced epithelial barrier dysfunction. The mechanisms underlying how lubiprostone regulates colon epithelial barrier function and visceral hyperalgesia in chronic stress remain unknown. Methods: Male rats were subjected to water avoidance stress for 10 consecutive days. Lubiprostone was administered daily during the stress phase. Visceromotor response to colorectal distension was measured. Human colon crypts and cell lines were treated with cortisol and lubiprostone. The transepithelial electrical resistance and FITC‐dextran permeability were assayed. Chromatin immunoprecipitation was conducted to assess glucocorticoid receptor binding at tight junction gene promoters. Key Results: Lubiprostone significantly decreased chronic stress‐induced visceral hyperalgesia in the rat (P < 0.05; n = 6). WA stress decreased occludin and claudin‐1 and increased claudin‐2 in rat colon crypts, which was prevented by lubiprostone. Cortisol treatment induced similar alterations of tight junction protein expression in Caco‐2/BBE cells (P < 0.05) and significantly changed paracellular permeability in monolayers (P < 0.01). These changes were blocked by lubiprostone. Glucocorticoid receptor and its binding at occludin promoter region were decreased in cortisol‐treated cells and human colon crypts, which was largely reversed by lubiprostone. In rat colonic cells, glucocorticoid receptor and its co‐chaperone proteins were down‐regulated after corticosterone treatment and lubiprostone reversed these changes. Conclusions & Inferences: Lubiprostone preferentially prevents chronic stress‐induced alterations of intestinal epithelial tight junctions, barrier function, and visceral hyperalgesia that was associated with modulation of glucocorticoid receptor expression and function. Lubiprostone preferentially prevents chronic stress‐induced alterations of intestinal epithelial tight junctions, barrier function, and visceral hyperalgesia that was associated with modulation of glucocorticoid receptor expression and function. [ABSTRACT FROM AUTHOR]

Background: Kruppel-like factor 2 (KLF2) is an important zinc-finger transcription factor that maintains endothelial homeostasis by its anti-inflammatory, -thrombotic, -oxidative, and -proliferative effects in endothelial cells. In light of the potent vasoprotective effects of KLF2, modulating KLF2 expression or function could give rise to new therapeutic strategies to treat cardiovascular diseases., Methods and Results: High-throughput drug screening based on KLF2 promoter luciferase reporter assay was performed to screen KLF2 activators. Real-time PCR and western blot were used to detect gene and protein expression. Identified KLF2 activator was orally administered to ApoE -/- mice to evaluate anti-atherosclerotic efficacy. By screening 2400 compounds in the Spectrum library, we identified suberanilohydroxamic (SAHA) acid, also known as vorinostat as a pharmacological KLF2 activator through myocyte enhancer factor 2. We found that SAHA exhibited anti-inflammatory effects and attenuated monocyte adhesion to endothelial cells inflamed with tumor necrosis factor alpha. We further showed that the inhibitory effect of SAHA on endothelial inflammation and ensuing monocyte adhesion was KLF2 dependent using KLF2-deficient mouse lung endothelial cells or KLF2 small interfering RNA- depleted human endothelial cells. Importantly, we observed that oral administration of SAHA reduced diet-induced atherosclerotic lesion development in ApoE -/- mice without significant effect on serum lipid levels., Conclusions: These results demonstrate that SAHA has KLF2-dependent anti-inflammatory effects in endothelial cells and provide the proof of concept that KLF2 activation could be a promising therapeutic strategy for treating atherosclerosis., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)