Endoplasmic Reticulum Stress-induced Endothelial Dysfunction Promotes Neointima Formation after Arteriovenous Grafts in Mice on High-fat Diet.

OBJECTIVE: Endothelial dysfunction is one candidate for triggering neointima formation after arteriovenous grafts (AVGs), but the factors mediating this process are unclear. The purpose of this study was to investigate the role of endoplasmic reticulum stress (ERS)-induced endothelial dysfunction in neointima formation following AVGs in high-fat diet (HFD) mice. METHODS: CCAAT-enhancer-binding protein-homologous protein (CHOP) knockout (KO) mice were created. Mice were fed with HFD to produce HFD model. AVGs model were applied in the groups of WT ND, WT HFD, and CHOP KO HFD. Human umbilical vein endothelial cells (HUVECs) were cultured with oxidized low density lipoprotein (ox-LDL) (40 mg/L) for the indicated time lengths (0, 6, 12, 24 h). ERS inhibitor tauroursodeoxycholic acid (TUDCA) was used to block ERS. Immunohistochemical staining was used to observe the changes of ICAM1. Changes of ERS were detected by real-time RT-PCR. Protein expression levels and ERS activation were detected by Western blotting. Endothellial cell function was determined by endothelial permeability assay and transendothelial migration assay. RESULTS: HFD increased neointima formation in AVGs associated with endothelial dysfunction. At the same time, ERS was increased in endothelial cells (ECs) after AVGs in mice consuming the HFD. In vitro, ox-LDL was found to stimulate ERS, increase the permeability of the EC monolayer, and cause endothelial dysfunction. Blocking ERS with TUDCA or CHOP siRNA reversed the EC dysfunction caused by ox-LDL. In vivo, knockout of CHOP (CHOP KO) protected the function of ECs and decreased neointima formation after AVGs in HFD mice. CONCLUSION: Inhibiting ERS in ECs could improve the function of AVGs.

Protective role of down-regulated microRNA-31 on intestinal barrier dysfunction through inhibition of NF-κB/HIF-1α pathway by binding to HMOX1 in rats with sepsis.

BACKGROUND: Intestinal barrier dysfunction is a significant clinical problem, commonly developing in a variety of acute or chronic pathological conditions. Herein, we evaluate the effect of microRNA-31 (miR-31) on intestinal barrier dysfunction through NF-κB/HIF-1α pathway by targeting HMOX1 in rats with sepsis. METHODS: Male Sprague-Dawley rats were collected and divided into the sham group, and the cecum ligation and perforation group which was subdivided after CACO-2 cell transfection of different mimic, inhibitor, or siRNA. Levels of serum D-lactic acid, diamine oxidase and fluorescence isothiocyanate dextran, FITC-DX concentration, and bacterial translocation were detected. Superoxidedismutase (SOD) activity and malondialdehyde (MDA) content were evaluated using the colorimetric method and an automatic microplate reader, respectively. Additionally, the levels of tumor necrosis factor, interleukin (IL)-6, and IL-10 were tested using enzyme-linked immunosorbent assay. The expression of miR-31, HMOX1, NF-κB, HIF-1α, IκB, ZO-1 and Occludin were assessed by reverse transcription quantitative polymerase chain reaction and Western blot analysis. RESULTS: Inhibition of miR-31 decreased intestinal mucosal permeability and intestinal barrier function. The increased levels of miR-31 could cause oxidative damage and affect the expression of inflammatory factors in intestinal tissue of rats. HMOX1 was confirmed as a target gene of miR-31. MiR-31 affected intestinal mucosal permeability and intestinal barrier function, as well as oxidative damage and inflammation level by regulating HMOX1. Down-regulation of miR-31 inhibited NF-κB/HIF-1α pathway related genes by regulating HMOX1 expression. Furthermore, inhibition of miR-31 increased survival rates of rats. CONCLUSION: Overall, the current study found that inhibition of miR-31 protects against intestinal barrier dysfunction through suppression of the NF-κB/HIF-1α pathway by targeting HMOX1 in rats with sepsis.

Effects of tanshinone IIA on the transforming growth factor ß1/Smad signaling pathway in rat cardiac fibroblasts.

OBJECTIVES: This study explores the mechanism of tanshinone IIA (TSN)-mediated inhibition of myocardial fibrosis by investigating the effect of TSN on transforming growth factor ß1 (TGFß1) signal transduction in rat cardiac fibroblasts (CFs). MATERIALS AND METHODS: CFs were isolated from neonatal Sprague-Dawley rats by trypsin digestion and differential adhesion and stimulated with 5 ng/mL TGFß1 and TSN (10(-6), 10(-5), or 10(-4) mol/L). The expression of fibronectin (FN) mRNA in the CFs was determined using reverse transcriptase-polymerase chain reaction and the protein expression of FN and Smads in CFs was detected using Western blot. The intracellular expression and localization of Smads in the CFs were analyzed using immunocytochemistry. RESULTS: TGFß1 induced the expression of FN and Smads in a time-dependent manner. At the end of the culture treatment, the mRNA expression of FN and the expression of phosphorylated Smad2/3 (p-Smad2/3) increased significantly (P < 0.01). TSN pretreatment (10(-5) and 10(-4) mol/L) reduced the expression of FN and p-Smad2/3 (P < 0.01) following TGFß1 stimulation and led to a significant decrease in the nuclear staining intensity and a positive rate of p-Smad2/3 (P < 0.05 and P < 0.01, respectively). CONCLUSION: The inhibitory effect of TSN on myocardial fibrosis may be associated with its inhibition of TGFß1-induced Smad2/3 phosphorylation and p-Smad2/3 nuclear translocation, which blocks the TGFß1/Smad signaling pathway in CFs.

[Changes of c-fos, c-jun mRNA expressions in cardiomyocyte hypertrophy induced by angiotensin II and effects of tanshinone II A].

OBJECTIVE: To investigate the changes of proto-oncogene c-fos, c-jun mRNA expression in angiotensin II (Ang II)-induced hypertrophy and effects of tanshinone II A (Tan) in the primary culture of neonatal rat cardiomyocytes. METHOD: Twelve neonatal Wistar rats aged one day old of clean grade and both sexes were selected to isolate and culture cardiomyocytes. The cardiomyocytes were divided into: normal control group, Ang II (10(-6) mol x L(-1)) group, Ang II (10(-6) mol x L(-1)) +Tan (10(-8) g x L(-1)) group, Ang II (10(-6) mol x L(-1)) + valsartan (10(-6) mol x L(-1)) group, Tan (10(-8) g x L(-1)) group, valsartan (10(-6) mol x L(-1)) group. The cardiomyocyte size was determined by phase contrast microscope, the rate of protein synthesis in cardiomyocytes was measured by 3H-leucine incorporation. The c-fos, c-jun mRNA expression of cardiomyocytes were assessed using reverse transcription polymerase chain reaction (RT-PCR). RESULT: Ang II was added to the culture medium and 30 min later, the c-fos, c-jun mRNA expression of cardiomyocytes increased significantly (P < 0. 01). After Ang II took effect for 24 h, the rate of protein synthesis in Ang II group increased more prominently than that in normal control group (P < 0.01). After Ang II took effect for 7 days, the size of cardiomyocyte in Ang II group increased obviously (P < 0. 05). If tanshinone II or valsartan was added to the culture medium before Ang II, both of them could inhibit the increase of c-fos, c-jun mRNA expression (P < 0.01), cardiomyocyte protein synthesis rate (P < 0.01), and cardiomyocyte size (P < 0.05) induced by Ang II. CONCLUSION: Tanshinone II could ameliorate Ang II-induced cardiomyocytes hypertrophy by inhabiting c-fos, c-jun mRNA expression.

Analysis of high risk factors related to acute respiratory distress syndrome following severe thoracoabdominal injuries / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the high risk factors related to acute respiratory distress syndrome(ARDS) following serious thoracoabdominal injuries.</p><p><b>METHODS</b>The clinical data of 282 patients with serious thoracoabdominal injuries were retrospectively studied. Univariate and Cox multivariate regression analysis were used to determine the risk factors related to ARDS following serious thoracoabdominal injuries.</p><p><b>RESULTS</b>The incidence of ARDS was 31.9% (90/282) in patients with serious thoracoabdominal injuries. The mortality caused by ARDS was 37.8% (34/90). The univariate analysis and multivariate analysis demonstrated that the clinical conditions such as elder age, shock, dyspnea, abnormal arterial blood gas, hemopneumothorax, pulmonary contusion, flail chest, coexisting pulmonary diseases, multiple abdominal injury and high ISS score were the independent high risk factors related to ARDS.</p><p><b>CONCLUSION</b>There are many high risk factors related to ARDS following severe thoracoabdominal injuries, which should be detected early and treated timely to decrease the incidence and mortality of A RDS.</p>