Silencing of circARHGAP12 inhibits the progression of atherosclerosis via miR-630/EZH2/TIMP2 signal axis.

Atherosclerosis (AS) is a common disease that seriously threatens human health. So far, the pathogenesis of AS has not been fully understood. This project investigates the effects of circARHGAP12 on AS and its regulatory mechanism. ApoE-/- knockout mice (ApoE) were adopted and reared with a high-fat diet to construct an AS model. Lentivirus was established to knock down the expression of circARHGAP12 in mice. After 12 weeks, the aorta was removed and the expression of circARHGAP12 was detected. Vascular oil red O staining was used to detect the degree of AS. The expression of inflammatory factors was detected by ELISA. Aortic smooth muscle cells (MASMCs) were cultured to evaluate the effects of circARHGAP12 on the phenotype of MASMCs. RNA pull-down and luciferase assay were used to verify the downstream target genes of circARHGAP12. In addition, the effects of circARHGAP12 on MASMCs proliferation and migration were detected by MTT and transwell assay. Compared with the normal group, the expression of circARHGAP12 in the MASMCs under ox-LDL treatment was elevated, and circARHGAP12 silencing could inhibit AS in vitro and in vivo. The results of the mechanism study showed that circARHGAP12 can directly bind with miR-630. In addition, miR-630 can also target EZH2 to modulate the transcription of TIMP2 and to influence the migration of MASMCs. circARHGAP12 is upregulated in AS. CircARHGAP12 knockdown can inhibit the progression of AS. This study expands on the role of circRNA in AS and provides potential targets for the treatment of AS.

MicroRNA-130a regulates neurological deficit and angiogenesis in rats with ischaemic stroke by targeting XIAP.

MicroRNAs (miRNAs) have already been proposed to be implicated in the development of ischaemic stroke. We aim to investigate the role of miR-130a in the neurological deficit and angiogenesis in rats with ischaemic stroke by regulating X-linked inhibitor of apoptosis protein (XIAP). Middle cerebral artery occlusion (MCAO) models were established by suture-occluded method, and MCAO rats were then treated with miR-130a mimics/inhibitors or/and altered XIAP for detection of changes of rats' neurological function, nerve damage and angiogenesis in MCAO rats. The oxygen-glucose deprivation (OGD) cellular models were established and respectively treated to determine the roles of miR-130a and XIAP in neuronal viability and apoptosis. The expression levels of miR-130a and XIAP in brain tissues of MCAO rats and OGD-treated neurons were detected. The binding site between miR-130a and XIAP was verified by luciferase activity assay. MiR-130a was overexpressed while XIAP was down-regulated in MCAO rats and OGD-treated neurons. In animal models, suppressed miR-130a improved neurological function, alleviated nerve damage and increased new vessels in brain tissues of rats with MCAO. In cellular models, miR-130a inhibition promoted neuronal viability and suppressed apoptosis. Inhibited XIAP reversed the effect of inhibited miR-130a in both MCAO rats and OGD-treated neurons. XIAP was identified as a target of miR-130a. Our study reveals that miR-130a regulates neurological deficit and angiogenesis in rats with MCAO by targeting XIAP.

LncRNA DIGIT Accelerates Tube Formation of Vascular Endothelial Cells by Sponging miR-134.

Atherosclerosis is one of the most prevalent and important cardiac diseases, involving the heart and brain. This study aimed to explore the impacts of lncRNA Divergent to GSC induced by TGF-b family signaling (DIGIT) on vascular endothelial cells tube-formation capacity so as to reveal the potentials of DIGIT in atherosclerosis therapy. DIGIT expression in human microvascular endothelial HMEC-1 cells was silenced by transfection with shRNAs-targeted DIGIT. The effects of DIGIT silence on cell viability, migration, apoptosis, and tube formation were then assessed. Additionally, the cross-regulation between DIGIT and miR-134, and between miR-134 and Bmi-1 was detected to further reveal through which mechanism (s) DIGIT mediated HMEC-1 cells. The results showed that DIGIT silence significantly reduced cell viability, migration, tube-like structures formation, and induced apoptosis in HMEC-1 cells. DIGIT worked as a sponge for miR-134, and the anti-growth, anti-migratory, and anti-tube-formation functions of DIGIT silence on HMEC-1 cells were abolished by miR-134 suppression. Bmi-1 was a target of miR-134, and Bmi-1 upregulation abolished miR-134 overexpression-diminished cell growth, migration, and tube formation of HMEC-1 cells. Furthermore, Bmi-1 upregulation activated PI3K/AKT and Notch signaling pathways. In conclusion, our study demonstrated that lncRNA DIGIT accelerated tube formation of vascular endothelial cells through sponging miR-134. Our findings suggest that DIGIT and miR-134 may be promising molecular targets for atherosclerosis therapy.

Volatile organic compound emissions from straw-amended agricultural soils and their relations to bacterial communities: A laboratory study.

A laboratory study was conducted to investigate volatile organic compound (VOC) emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66days under non-flooded and flooded conditions. The results indicated that ethene, propene, ethanol, i-propanol, 2-butanol, acetaldehyde, acetone, 2-butanone, 2-pentanone and acetophenone were the 10 most abundant VOCs, making up over 90% of the total VOCs released under the two water conditions. The mean emission of total VOCs from the amended soils under the non-flooded condition (5924ng C/(kg·hr)) was significantly higher than that under the flooded condition (2211ng C/(kg·hr)). One "peak emission window" appeared at days 0-44 or 4-44, and over 95% of the VOC emissions occurred during the first month under the two water conditions. Bacterial community analysis using denaturing gradient gel electrophoresis (DGGE) showed that a relative increase of Actinobacteria, Bacteroidetes, Firmicutes and γ-Proteobacteria but a relative decrease of Acidobacteria with time were observed after straw amendments under the two water conditions. Cluster analysis revealed that the soil bacterial communities changed greatly with incubation time, which was in line with the variation of the VOC emissions over the experimental period. Most of the above top 10 VOCs correlated positively with the predominant bacterial species of Bacteroidetes, Firmicutes and Verrucomicrobia but correlated negatively with the dominant bacterial species of Actinobacteria under the two water conditions. These results suggested that bacterial communities might play an important role in VOC emissions from straw-amended agricultural soils.

Report: Analysis on pathogen distribution and drug-resistance of incision infection caused by vascular operation.

To investigate pathogen distribution and drug resistance of incision infection caused by vascular operation to reduce postoperative incision infection, this paper retrospectively reviewed and analyzed 635 in-hospital patients taking vascular operation during Jan. 2008 and Dec. 2012. Analyzed data were statistically processed by SPSS 13.0 software, which resulted in 16 infected cases with 2.52% infection rate. A total of 27 pathogens wasisolated from specimens submitted for inspection, including 17 strains of Gram positive bacteria (62.96%) and 10 Gram negative bacteria (37.04%). Besides high sensitivity to imipenem, all bacteria were able to resist antibacterial drugs. Incision infection is proved in this research to be reduced effectively by some means, like complication correction before operation and reasonable application of antibacterial drugs after operation. While during an operation, it is necessary to operate strictly in a bacterium-free environment and wash incisions thoroughly.

MiR-18a-5p contributes to enhanced proliferation and migration of PASMCs via targeting Notch2 in pulmonary arterial hypertension.

AIM: This study is undertaken to investigate the role and molecular mechanisms of miR-18a-5p in regulating pulmonary arterial hypertension (PAH) pathogenesis. METHODS: Gene expression and protein levels were determined by qRT-PCR and western blot, respectively; Cell counting kti-8 and Transwell migration assays were used to determine the biological functions of miR-18a-5p in pulmonary arterial smooth muscle cells (PASMCs); bioinformatics analysis, luciferase reporter assays were used to elucidate the mechanisms of miR-18a-5p. RESULTS: MiR-18a-5p was up-regulated in the clinical samples from PAH patients. PASMCs treated with hypoxia exhibited enhanced proliferative ability and upregulated miR-18a-5p expression. Knockdown of miR-18a-5p attenuated hypoxia-induced hyper-proliferation and enhanced migratory potential of PASMCs; while miR-18a-5p overexpression promoted PASMC proliferation and migration. Further mechanistic studies showed that Notch2 was a direct target of miR-18a-5p and was repressed by miR-18a-5p overexpression. The rescue studies indicated that Notch2 overexpression counteracted the enhanced proliferation and migration induced by miR-18a-5p mimics in PASMCs. Similarly, Notch2 overexpression also block the effects caused by hypoxia in PASMCs. Moreover, Notch2 expression was down-regulated in the PAH patients and was negatively correlated with miR-18a-5p expression. In vivo animal studies further revealed the up-regulation of miR-18a-5p and the down-regulation of Notch2 in the PAH rats. CONCLUSIONS: Collectively, this study identified the up-regulated miR-18a-5p in the PAH patients; our data suggest that miR-18a-5p contributes to the enhanced proliferation and migration of PASMCs via repressing Notch2 expression.

Influence of DNA methyltransferase 3b on FHIT expression and DNA methylation of the FHIT promoter region in hepatoma SMMC-7721 cells.

BACKGROUND: Alterations in DNA methylation occur during the pathogenesis of human tumors. In this study, we investigated the influence of DNA methyltransferase 3b (DNMT3b) on fragile histidine trial (FHIT) expression and on DNA methylation of the FHIT promoter region in the hepatoma cell line SMMC-7721. METHODS: DNMT3b siRNA was used to down-regulate DNMT3b expression. DNMT3b and FHIT proteins were determined by Western blotting. Methylation-specific PCR was used to analyze the methylation status of the FHIT gene. RESULTS: After DNMT3b siRNA transfection, the expression of DNMT3b was inhibited in SMMC-7721 cells, and the expression of FHIT was significantly higher than that in the control group. There was no significant difference in methylation status between the DNMT3b siRNA transfected cells and control cells. CONCLUSION: DNMT3b may play an important role in regulation of FHIT expression in hepatoma SMMC-7721 cells, but not through methylation of the FHIT promoter.

[Influence of DNA methyltransferase 3b on the expression of cyclin D1 gene and methylation of its promoters in human hepatocellular carcinoma cells].

OBJECTIVE: To investigate the influence of DNA methyltransferase (DNMT) 3b on the expression of cyclin D1 gene and methylation of its promoters and to investigate the function of DNMT3b. METHODS: Human hepatocellular carcinoma cells of the line SMMC7721 were cultured and randomly divided into 3 groups: experimental group transfected with siRNA to silence the DNMT3b, control group transfected with control siRNA, and normal group without transfection. The transfection rate of siRNA was detected by fluorescence microscopy. MTT method was used to measure the survival rate of the SMMC-7721 cells. Western blotting and cell proliferation assay were performed to evaluate the expression of cyclin D1 and cell growth. Methylation specific PCR (MSP) was performed to investigate whether the promoter of cyclin D1 was methylated. RESULTS: Fluorescence microscopy showed that the transfection rate of siRNA was over 90%. MTT method showed that 24 h and 36 h after transfection the A value and survival rate of the SMMC7721 cells of the experimental group were both significantly higher than those of the control d normal groups (all P < 0.05). Western blotting showed that the expression levels of DNMT3b and cyclin D1 of the experimental group decreased significantly compared with the control and the normal groups. MSP showed no obvious change of the state of methylation among the 3 groups. CONCLUSIONS: DNMT3b may regulate the expression and the function of cyclin D1 gene in the human hepatocellular carcinoma cells, but does not change its methylation state. DNMT3b may play their role as a signal transduction element rather than as a DNA methyltransferase.

Exosomes derived from oxLDL-stimulated macrophages induce neutrophil extracellular traps to drive atherosclerosis.

This study aimed to investigate the role and underlying mechanism of exosomes secreted by oxidized low-density lipoprotein (oxLDL)-stimulated macrophages in the progression of atherosclerosis (AS). Exosomes from peripheral blood of AS patients or oxLDL-treated macrophages were co-cultured with human neutrophils. Neutrophil extracellular traps (NETs) were detected by immunofluorescence staining. The levels of inflammatory cytokines were quantified by enzyme-linked immunosorbent assay (ELISA). The expression levels of miR-146a and superoxide dismutase 2 (SOD2) were determined by quantitative real-time PCR (qRT-PCR) and western blot. The generation of intracellular reactive oxygen species (ROS) was observed by using dichlorofluorescin diacetate (DCFH-DA). ApoE-deficient mice were fed with high-fat diet (HFD) to induce AS. Atherosclerotic plaques were evaluated by Oil red O (ORO) and hematoxylin-eosin (HE) staining. Our results showed that miRNA-146a was enriched in serum-derived exosomes of AS patients and oxLDL-treated macrophage THP-1-derived exosomes. Importantly, exosomal miR-146a secreted by oxLDL-treated macrophages promoted ROS and NETs release via targeting SOD2. In addition, intravenous administration of oxLDL-treated THP-1 cells-derived exosomes into AS mice significantly deteriorated AS in vivo. Our findings indicate that exosomal miR-146a derived from oxLDL-treated macrophages promotes NETs formation via inducing oxidative stress, which might provide a novel scientific basis for the understanding of AS progression.

Effects of integrin α5ß1 on the proliferation and migration of human aortic vascular smooth muscle cells.

Integrin (ITG) α5ß1 is a dominant fibronectin receptor that is abundantly expressed on the surface of vascular smooth muscle cells (VSMCs). However, the association between integrin α5ß1 and the proliferation and migration of VSMCs has yet to be elucidated. The aim of the present study was to characterize the roles of ITGα5 and ITGß1 in the proliferation and migration of VSMCs, and to determine the effects of ITGα5ß1 on integrin-linked kinase (ILK) and focal adhesion kinase (FAK) mRNA expression. Lentiviral expression vectors as well as RNA interference vectors of ITGα5 and ITGß1 were successfully constructed and transfected into VSMCs to obtain ITGα5­ and ITGß1­overexpressing or -silenced cells, respectively. Cell cycle distribution, proliferation and migration were analyzed in the transfected VSMCs in order to clarify the roles of ITGß1 and ITGα5 in the proliferation and migration of VSMCs. ITGß1 was markedly associated with the proliferation and migration of VSMCs, and FAK was shown to be involved in the signaling pathways of ITGß1. ITGα5 did not exert any effects on VSMCs. The results of the present study may provide a possible therapeutic target for the prevention and treatment of early vascular disease associated with VSMCs.

Meta-analysis of the association between angiotensin-converting enzyme I/D polymorphism and aortic aneurysm risk.

BACKGROUND: Angiotensin-converting enzyme (ACE) I/D polymorphism has been indicated to be correlated with aortic aneurysm (AA) susceptibility, but study results are still debatable. Thus, a meta-analysis was conducted. METHODS: Databases including PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. RESULTS: Ten studies with 3557 cases and 5231 controls were included in this meta-analysis. The association between ACE I/D genotype and AA risk was significant (OR=1.30; 95%CI, 1.07-1.57; p<0.01; I(2)=68%). When stratified by ethnicity, a significantly elevated risk was observed in Caucasians (OR=1.31; 95%CI, 1.07-1.61; p<0.01; I(2)=71%). In the abdominal AA subgroup, a significantly increased risk was observed (OR=1.29; 95%CI, 1.03-1.62; p=0.02; I(2)=73%). However, ACE I/D polymorphism was not associated with thoracic AA risk (OR=1.33; 95%CI, 0.85-2.07; p=0.21; I(2)=52%). Subgroup analysis on blood pressure status showed that an increased risk was found in hypertensive patients (OR=1.52; 95%CI, 1.02-2.26; p=0.04; I(2)=0%) but not in normotensive subjects (OR=1.46; 95%CI, 0.72-2.96; p=0.30; I(2)=25%). CONCLUSIONS: In conclusion, this meta-analysis suggested that ACE I/D polymorphism is a risk factor for AA.

Diagnosis and Treatment of Vascular Surgery Related Infection.

Surgical site infection (SSI) is an important component of infections acquired from hospital. The most significant feature of vascular surgery different from other surgeries is frequent application of artificial grafts. Once SSI occurs after vascular operations with grafts, it might results in a serious disaster. Staphylococcus aureus and coagulase-negative Staphylococcus are the most common pathogenic bacteria for SSI after vascular surgery. Although SSI in vascular surgery often lacks of typical clinical characters, some clinical symptoms, laboratory data and certain imaging procedures may help to diagnose. In most cases of SSI after vascular procedures, the artificial grafts must be removed and sensitive antibiotics should be administered. However, for different cases, personalized management plan should be made depending on the severity and location of SSI.