Aqueous extract of Salvia miltiorrhiza Bunge-Radix Puerariae herb pair ameliorates diabetic vascular injury by inhibiting oxidative stress in streptozotocin-induced diabetic rats.

Vascular diabetic complications are the leading cause of mortality and morbidity for diabetes. The present study was designed to investigate the protective effect of herb pair Salvia miltiorrhiza Bunge-Radix Puerariae (DG) on diabetic vascular injury induced by streptozotocin. The protective effect of DG was determined by oral administration of DG (50 and 200 mg/kg) in rats and on high glucose (HG)-induced endothelial injury. DG showed no effect on body weight, fasting blood glucose (FBG) but decreased the serum levels of insulin, nitric oxide (NO), hydrogen peroxide (H2O2), malondialdehyde (MDA), soluble intercellular cell adhesion molecule-1 (s-ICAM-1) and vascular cell adhesion molecule-1 (s-VCAM-1), and increased superoxide dismutase (SOD) and catalase (CAT) levels. The pathological alterations of aorta was improved by DG. Furthermore, the increased expression of ICAM-1,VCAM-1, NOX2, and NOX4 in aorta were inhibited by DG. HG-induced endothelial ROS formation, ICAM-1,VCAM-1, NOX4 expression and monocyte-endothelial adhesion were dramatically suppressed by DG as well. In addition, both GKT137831, a NOX4 inhibitor, and PDTC, a NF-κB inhibitor, could significantly inhibited HG-induced ICAM-1, VCAM-1 expression and monocyte-endothelial adhesion. These results suggested that DG improved diabetic vascular injury possibly by reducing oxidative stress, which provides scientific evidence for the application of DG for diabetic vascular therapy.