Cyclooxygenase 2, toll-like receptor 4 and interleukin 1β mRNA expression in atherosclerotic plaques of type 2 diabetic patients

Inflammation has a prominent role in the development of atherosclerosis. Type 2 diabetes could contribute to atherosclerosis development by promoting inflammation. This status might accelerate changes in intrinsic vascular wall cells and favor plaque formation. Cyclooxygenase 2 (COX-2) is highly expressed in atherosclerotic plaques. COX-2 gene expression is promoted through activation of toll-like receptor 4 (TLR4) and pro-inflammatory cytokine interleukin 1 beta (IL1-beta). Aim of this study is to investigate whether expression profiles of pro-inflammatory genes such as COX-2, TLR4 and IL1-beta in atherosclerotic plaques are altered in type 2 diabetes (T2D). Total RNA was isolated from plaques of atherosclerotic patients and expression of COX-2, TLR4, IL1-beta analyzed using real-time PCR. Histological analysis was performed on sections of the plaque to establish the degree of instability. Statistically significant differences in mRNA expression of COX-2 and IL1-beta were found in plaques of T2D compared with non-T2D patients. A multi-variable linear regression model suggests that COX-2 mRNA expression is affected by T2D pathology and IL1-beta mRNA expression in atherosclerotic plaques. Our results support the hypothesis that T2D pathology contributes in vivo to increase the inflammatory process associated with the atherosclerotic plaque formation, as shown by an increment of COX-2 and IL1-beta mRNA expression.