Association between thrombomodulin polymorphisms and coronary artery disease risk: a meta-analysis

Relationship between thrombomodulin gene polymorphism and susceptibility to venous thromboembolism: A protocol for systematic review and meta-analysis

BACKGROUND

Previous studies displayed that thrombomodulin gene polymorphisms are closely associated with venous thromboembolism (VTE), while the results are inconsistent. Therefore, we conducted a meta-analysis to accurately determine the association between thrombomodulin gene polymorphism and the risk of VTE.

METHODS

Wanfang, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, the Chongqing VIP Chinese Science and Technology Periodical Database, PubMed, EmBase, and Web of Science databases were searched, and the time to build the database was set until January 2021. The association between thrombomodulin gene polymorphism and the risk of VTE was evaluated. Meta-analysis was performed with STATA 16.0 software, and the odds ratio and its 95% confidence interval were applied to estimate the relationship between thrombomodulin gene polym'orphism and the risk of VTE.

RESULTS

The results of this meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This meta-analysis will summarize the relationship between thrombomodulin genepolymorphism and VTE risk.

ETHICS AND DISSEMINATION

Ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. This review would be disseminated in a peer-reviewed journal or conference presentations.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/UEHJP.

Evidence of epigenetic alterations in thrombosis and coagulation: A systematic review

Thrombosis in the context of Cardiovascular disease (CVD) affects mainly the blood vessels supplying the heart, brain and peripheries and it is the leading cause of death worldwide. The pathophysiological thrombotic mechanisms are largely unknown. Heritability contributes to a 30% of the incidence of CVD. The remaining variation can be explained by life style factors such as smoking, dietary and exercise habits, environmental exposure to toxins, and drug usage and other comorbidities. Epigenetic variation can be acquired or inherited and constitutes an interaction between genes and the environment. Epigenetics have been implicated in atherosclerosis, ischemia/reperfusion damage and the cardiovascular response to hypoxia. Epigenetic regulators of gene expression are mainly the methylation of CpG islands, histone post translational modifications (PTMs) and microRNAs (miRNAs). These epigenetic regulators control gene expression either through activation or silencing. Epigenetic control is mostly dynamic and can potentially be manipulated to prevent or reverse the uncontrolled expression of genes, a trait that renders them putative therapeutic targets. In the current review, we systematically studied and present available data on epigenetic alterations implicated in thrombosis derived from human studies. Evidence of epigenetic alterations is observed in several thrombotic diseases such as Coronary Artery Disease and Cerebrovascular Disease, Preeclampsia and Antiphospholipid Syndrome. Differential CpG methylation and specific histone PTMs that control transcription of prothrombotic and proinflammatory genes have also been associated with predisposing factors of thrombosis and CVD, such us smoking, air pollution, hypertriglyceridemia, occupational exposure to particulate matter and comorbidities including cancer, Chronic Obstructive Pulmonary Disease and Chronic Kidney Disease. These clinical observations are further supported by in vitro experiments and indicate that epigenetic regulation affects the pathophysiology of thrombotic disorders with potential diagnostic or therapeutic utility.

Thrombomodulin gene c.1418C>T polymorphism and risk of recurrent venous thromboembolism

Thrombomodulin gene (THBD) is a critical cofactor in protein C anticoagulant system. THBD c.1418C>T polymorphism is reported to be associated with higher risk of primary venous thromboembolism (VTE) but its role in VTE recurrence is unknown. The aim of this study was to investigate the role of THBD polymorphism in VTE recurrence. THBD c.1418C>T polymorphism was genotyped by using Taqman polymerase chain reaction in a prospective population based study of 1465 consecutive objectively verified VTE patients. Uni- and multivariate Cox regression were performed for the risk assessment of VTE recurrence. Patients who had VTE before inclusion or had recurrence or died during anticoagulant treatment were excluded. Among the remaining (N = 1046) patients, 126 (12.05 %) had VTE recurrence during the follow up period (from 1998 to 2008). THBD polymorphism was not significantly associated with risk of VTE recurrence in the univariate [Hazard ratio (HR) 1.11, 95 % confidence interval (CI) 0.78-1.59, p = 0.55] as well as the multivariate analysis adjusted for age, sex and thrombophilia (HR 1.11, 95 % CI 0.78-1.59, p = 0.54). Similarly, in unprovoked first VTE (n = 614), no association was observed between THBD polymorphism and risk of VTE recurrence (HR 1.22 and 95 % CI 0.78-1.89, p = 0.38). In this prospective study, our results do not suggest a predictive role for THBD c.1418C>T polymorphism in VTE recurrence.

Association of Thrombomodulin Gene Polymorphisms with Susceptibility to Atherosclerotic Diseases: A Meta-Analysis

Previous studies have proved that the dysfunction of thrombomodulin (TM) plays an important role in the pathogenesis of atherosclerotic diseases. In order to reveal their inherent relationship, we conducted a meta-analysis to uncover the association between two polymorphisms -33G/A and Ala455Val (c.1418C>T) in the TM gene and atherosclerotic diseases. We carried out a systematic search in PubMed, Science Direct, BIOSIS Previews, SpringerLink, the Cochrane library, the Chinese National Knowledge Infrastructure, the Chinese Biomedical Database, the Wei Pu database, and the Wanfang Database. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were computed to show the association. We included 22 eligible studies which involved 5472 patients and 7786 controls. There were statistically significant associations between -33G/A polymorphisms in TM and the MI group under the Allele and Recessive models in Asians (G vs. A: OR = 0.67, 95%CI = 0.56-0.78, P < 0.00001; GG vs. GA+AA: OR = 0.66, 95%CI = 0.56-0.78, P < 0.00001). However, these findings of the overall and subgroups showed that Ala455Val polymorphisms did not have any relationship with atherosclerotic diseases. After Bonferroni correction, the above associations remained statistically significant. This meta-analysis provides robust evidence of association between the -33G/A polymorphism in the TM gene and the risk of myocardial infarction in Asians. The A allele may increase the incidence of MI in Asians. However, the Ala455Val variant was not associated with atherosclerotic risk. Further studies with adequate sample size are needed to verify our findings.

Effect of apolipoprotein A1 genetic polymorphisms on lipid profiles and the risk of coronary artery disease

Background

The disorder of lipid metabolism and genetic predisposition are major risk factors for coronary artery disease (CAD). Variants in the apolipoprotein A1 (APOA1) gene play an important role in the regulation of lipids. The objective of the present study was to investigate the effect of two polymorphisms (-75 G/A and +83 C/T) of APOA1 on lipid profiles and the risk of CAD.

Methods

A total number of 300 subjects with CAD and 300 age and sex matched healthy controls were enrolled for the study. Genotyping of the APOA1 was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) combined with gel electrophoresis, and then confirmed by direct sequencing.

Results

The frequencies of APOA1 -75 AA genotype [odds ratio (OR) =0.50, 95 % confidence interval (CI) = 0.28, 0.88; P = 0.02] and APOA1 -75 A allele (OR =0.76, 95 % CI = 0.59, 0.98; P = 0.04) were significantly lower in CAD than in controls. The APOA1 -75 A allele was significantly associated with increasing serum concentrations of ApoA1 and high-density lipoprotein cholesterol (HDL-C) (P < 0.001).

Conclusions

The individuals with the APOA1 -75 A allele were likely to have a lower risk of CAD as a result of its effect on higher serum concentrations of ApoA1 and HDL-C.