Association between fine particulate matter and coronary heart disease: A miRNA microarray analysis

Several studies have reported an association between residential surrounding particulate matter with an aerodynamic diameter ≤2.5 μm (PM_2.5) and coronary heart disease (CHD). However, the underlying biological mechanism remains unclear. To fill this research gap, this study enrolled a residentially stable sample of 942 patients with CHD and 1723 controls. PM_2.5 concentration was obtained from satellite-based annual global PM_2.5 estimates for the period 1998-2019. MicroRNA microarray and pathway analysis of target genes was performed to elucidate the potential biological mechanism by which PM_2.5 increases CHD risk. The results showed that individuals exposed to high PM_2.5 concentrations had higher risks of CHD than those exposed to low PM_2.5 concentrations (odds ratio = 1.22, 95% confidence interval: 1.00, 1.47 per 10 μg/m³ increase in PM_2.5). Systolic blood pressure mediated 6.6% of the association between PM_2.5 and CHD. PM_2.5 and miR-4726-5p had an interaction effect on CHD development. Bioinformatic analysis demonstrated that miR-4726-5p may affect the occurrence of CHD by regulating the function of RhoA. Therefore, individuals in areas with high PM_2.5 exposure and relative miR-4726-5p expression have a higher risk of CHD than their counterparts because of the interaction effect of PM_2.5 and miR-4726-5p on blood pressure.