Increased TNF-α, IL-6, PAI-1, leptin, and resistin, and decreased adiponectin promote insulin resistance, leading to impaired glucose management and diabetes. Some adipokines also affect endothelial function and the coagulation system, promoting atherosclerosis. The low-grade inflammatory state created by abnormal adipokine levels is likely an important connection between metabolic syndrome and cardiovascular disease.
Adipokines play several roles in the atherosclerotic inflammatory process:
- TNF-α activity produces inflammatory changes in vascular tissue and adhesion molecules. This increases the ability of monocytes to adhere to vessel walls.
- Resistin also promotes cell adhesion.
- Angiotensin II from angiotensinogen enhances the adhesion process of monocytes and platelets to vessel walls.
- When glucose levels are increased, leptin assists in the incorporation of lipids by enhancing the uptake of cholesterol by macrophages.
- IL-6 enhances the inflammatory process and increases CRP.
- If there are ruptured atherosclerotic plaques, PAI-1 increases the probability of thrombus formation and inhibits fibrin clot lysis.
