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Increasing evidence showed that abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are common event in the pathophysiology of many vascular diseases, including atherosclerosis and restenosis after angioplasty. Among the underlying mechanisms, oxidative stress is one of the principal contributors to the proliferation and migration of VSMCs. Oxidative stress occurs as a result of persistent production of reactive oxygen species (ROS). Recently, the protective effects of peroxisome proliferator-activated receptor γ (PPARγ) against oxidative stress/ROS in other cell types provide new insights to inhibit the suggests that PPARγ may regulate VSMCs function. However, it remains unclear whether activation of PPARγ can attenuate oxidative stress and further inhibit VSMC proliferation and migration. In this study, we therefore investigated the effect of PPARγ on inhibiting VSMC oxidative stress and the capability of proliferation and migration, and the potential role of mitochondrial uncoupling protein 2 (UCP2) in oxidative stress. It was found that platelet derived growth factor-BB (PDGF-BB) induced VSMC proliferation and migration as well as ROS production; PPARγ inhibited PDGF-BB-induced VSMC proliferation, migration and oxidative stress; PPARγ activation upregulated UCP2 expression in VSMCs; PPARγ inhibited PDGF-BB-induced ROS in VSMCs by upregulating UCP2 expression; PPARγ ameliorated injury-induced oxidative stress and intimal hyperplasia (IH) in UCP2-dependent manner. In conclusion, our study provides evidence that activation of PPARγ can attenuate ROS and VSMC proliferation and migration by upregulating UCP2 expression, and thus inhibit IH following carotid injury. These findings suggest PPARγ may represent a prospective target for the prevention and treatment of IH-associated vascular diseases.

Several studies have investigated whether the polymorphism in the apolipoprotein A5 (APOA5) is associated with type 2 diabetes mellitus (T2DM) risk. However, those studies have produced inconsistent results. The purpose of this study was to investigate whether the APOA5 -1131T/C polymorphism (rs662799) confers significant susceptibility to T2DM using a meta-analysis.PubMed, Embase, Web of Science, Cochrane database, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0.A total of 19 studies included 4,767 T2DM cases and 10,370 controls (four studies involving 555 T2DM cases and 2958 controls were performed among Europeans and 15 studies involving 4212 T2DM cases and 7412 controls were performed among Asians) were combined showing significant association between the APOA5 -1131T/C polymorphism and T2DM risk (for C allele vs. T allele: OR = 1.28, 95% CI = 1.17-1.40, p

BACKGROUND: Numerous epidemiological studies have evaluated the associations between ATP-binding cassette transporter 1 (ABCA1) R219K (rs2230806) and M883I (rs4149313) polymorphisms and atherosclerosis (AS), but results remain controversial. The purpose of the present study is to investigate whether these two polymorphisms facilitate the susceptibility to AS using a meta-analysis. METHODS: PubMed, Embase, Web of Science, Medline, Cochrane database, Clinicaltrials.gov, Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI, Google Scholar and Baidu Library were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0. RESULTS: Forty-seven articles involving 58 studies were included in the final meta-analysis. For the ABCA1 R219K polymorphism, 42 studies involving 12,551 AS cases and 19,548 controls were combined showing significant association between this variant and AS risk (for K allele vs. R allele: OR = 0.77, 95% CI = 0.71-0.84, P

BACKGROUND: Epidemiological studies have evaluated the association between nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22(phox) C242T polymorphism and risk of ischemic cerebrovascular disease (ICVD), but the results remain inconclusive. This meta-analysis was therefore designed to clarify these controversies. METHODOLOGY/PRINCIPAL FINDINGS: Systematic searches of electronic databases Embase, PubMed and Web of Science, as well as hand searching of the references of identified articles and the meeting abstracts were performed. Statistical analyses were performed using software Review Manager (Version 5.1.7) and Stata (Version 11.0). The pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were performed. Fixed or random effects model was separately used depending on the heterogeneity between studies. Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 6 studies including 1,948 cases and 2,357 controls were combined showing no statistical evidence of association between NADPH oxidase p22(phox) C242T polymorphism and overall ICVD (allelic model: OR = 1.08, 95%CI = 0.93-1.26; additive model: OR = 1.33, 95%CI = 0.81-2.17; dominant model: OR = 1.00, 95%CI = 0.86-1.15; recessive model: OR = 1.06, 95%CI = 0.77-1.45). Significant association was found in large-artery atherosclerotic stroke subgroup (allelic model: OR = 1.12, 95%CI = 0.88-1.41; additive model: OR = 1.36, 95%CI = 0.60-3.09; dominant model: OR = 1.25, 95%CI = 0.74-2.11; recessive model: OR = 2.17, 95%CI = 1.11-4.23). No statistical evidence of significant association was observed for small-vessel occlusive stroke, as well as Asian subgroup and Caucasian subgroup. Statistical powers on the combined sample size (total and subgroup) were all lower than 80%. CONCLUSIONS/SIGNIFICANCE: This meta-analysis indicates that NADPH oxidase p22(phox) C242T polymorphism is more associated with large-artery atherosclerotic stroke than small-vessel occlusive stroke. However, this conclusion should be interpreted with caution due to the small sample size. Larger sample-size studies with homogeneous ICVD patients and well-matched controls are required.

BACKGROUND: Epidemiological studies have evaluated the association between tumor necrosis factor α (TNF-α) single nucleotide polymorphisms (SNPs) and duodenal ulcer (DU), but the results remain inconclusive. The aim of this study was to perform a meta-analysis to investigate a more authentic association between TNF-α SNPs and DU. METHODS: We performed the meta-analysis by searching PubMed, Embase, and Web of Science databases from the first available year to Sep. 5, 2012. Additionally, checking reference lists from identified articles, reviews, and the abstracts presented at related scientific societies meetings were also performed. All case-control studies investigating the association between TNF-α SNPs and DU risk were included. The association was assessed by odds ratio (OR) with 95% confidence interval (CI). Publication bias was analyzed by Begg's funnel plot and Egger's regression test. RESULTS: A total of sixteen studies reporting TNF-α -308G/A, -1031T/C, -863C/A, -857C/T, and -238G/A polymorphism were included in our final meta-analysis. There was no statistically significant association between -308G/A polymorphism and DU in the overall study population, as well as subgroup analyses by ethnicity, study design, and H. pylori status. As for -1031T/C, -863C/A, -857C/T, and -238G/A, results of our meta-analyses showed no statistical evidence of significant association. Power calculation on the combined sample size showed that the statistical powers were all lower than 80% for all the meta-analyses. CONCLUSIONS: The data suggests that there is no statistical evidence of significant association between the studied TNF-α SNPs and DU. However, this conclusion should be interpreted with caution as low statistical powers were revealed by power calculations. In future, larger sample-size studies with homogeneous DU patients and well-matched controls are required.

BACKGROUND: Epidemiological studies have evaluated the association between apolipoprotein E (ApoE) gene polymorphism and coronary artery disease (CAD) risk which developed inconsistent conclusions. To derive a more precise estimation of the relationship in Chinese population, we performed this meta-analysis. METHODS: Databases, including PubMed, EMbase, Web of Science, CBMdisc and CNKI, were searched to get the genetic association studies. Additionally, hand searching of the references of identified articles were performed. All the statistical tests were performed using Review Manager 5.1.2 and Stata 11.0. RESULTS: We identified a total of 40 studies, including 4,564 CAD cases and 3,985 controls. The results showed evidence for significant association between ApoE ε4 allele and CAD risk (for ε2/ε4 vs. ε3/ε3: OR = 1.86, 95% CI = 1.42-2.43, p

Introduction ATP-binding cassette transporter 1 (ABCA1), a member of the ATP-binding cassette family, plays a critical role in the development of atherosclerosis (AS). This meta-analysis was performed to assess the associations of ABCA1 C69T and V825I polymorphisms with AS susceptibility. Materials and methods A comprehensive search was conducted to identify all eligible studies from PubMed, Embase, Web of Science, Cochrane database, CBMdisc, CNKI and Google Scholar. Additionally, hand searching of the references of identified articles was performed. All statistical analyses were done with Review Manager 5.1.4 and Stata 11.0. Results Eleven articles involving 14 studies were included in the final meta-analysis. For the ABCA1 C69T polymorphism, six studies involving 1854 AS cases and 5744 controls were combined showing significant association between this variant and AS risk (for T allele vs. C allele: OR =1.44, 95% CI =1.04-1.24, p =0.005; for T/T vs. C/C: OR =1.39, 95% CI =1.12-1.73, p =0.003; for T/T vs. C/T+C/C: OR =1.34, 95% CI =1.09-1.65, p =0.006; for T/T+C/T vs. C/C: OR =1.13, 95% CI =1.01-1.27, p =0.040). For the ABCA1 V825I polymorphism, eight studies involving 2026 AS cases and 8696 controls were combined. There was no significant association between the variant and AS risk (for I allele vs. V allele: OR =1.18, 95% CI =0.90-1.53, p =0.230; for I/I vs. V/V: OR =1.29, 95% CI =0.75-2.23, p =0.360; for I/I vs. V/I+V/V: OR =1.40, 95% CI =0.87-2.26, p =0.160; for I/I+V/I vs. V/V: OR =1.15, 95% CI =1.00-1.33, p =0.060). Conclusions This meta-analysis suggested that the ABCA1 C69T polymorphism was associated with an increased AS risk. Furthermore, there was no significant association between the ABCA1 V825I polymorphism and AS risk. [ABSTRACT FROM AUTHOR]