Effects of moderate-intensity aerobic exercise on coronary artery structure and function in type 2 diabetic rats

Aerobic exercise is an effective intervention for T2DM, but its impact on coronary artery function in T2DM remains unclear due to limitations in non-invasive assessments. This study aimed to evaluate the effects of moderate intensity aerobic exercise (MIAE) on coronary artery fibrosis and vascular function in T2DM rats. Male Sprague-Dawley rats were randomly assigned to four groups: control (CON), control exercise (CE), T2DM (DM), and T2DM exercise (DE). The exercise groups underwent eight weeks of MIAE. Blood glucose levels were measured by glucometer, TC, TG, LDL-C, HDL-C, insulin, TNF-α, IL-1β, and IL-6 levels were assessed by Elisa. Coronary artery morphology was analyzed by HE and multiphoton microscopy. Vascular ring experiments evaluated the endothelium-dependent and independent vasorelaxation of the coronary artery. Eight weeks of MIAE significantly improved circulating glucose-lipid metabolism (P < 0.05) and reduced TNF-α, IL-6, and IL-1β (P < 0.05) in T2DM rats. Following MIAE, coronary artery collagen and fiber content were significantly reduced, accompanied by notable improvements in endothelial and smooth muscle function. MIAE reduces vascular fibrosis and improves coronary endothelial cell and smooth muscle function by regulating disturbances in circulating glucose-lipid metabolism and inhibiting inflammatory responses.