Antioxidants and Antiatherosclerotic Effects of Chinese Medicinal Herb Salvia Miltiorrhiza

Recent studies have suggested that atherosclerosis is triggered by low-density lipoprotein (LDL) oxidation and endothelial dysfunction. Salvia miltiorrhiza (SM) is a Chinese medicinal herb widely used for the treatment of cardiovascular disorder. SM produces many water-soluble polyphenolic antioxidants. Among them, salvianolic acid B (Sal B) strongly inhibited human LDL oxidation in vitro. To evaluate the antiatherosclerotic potential of SM, cholesterol-fed NZW rabbits and apoE(-) mice were used as the animal models, LDL samples obtained from treated animals were more resistant to oxidation ex vivo. The α-tocopherol contents of LDL were significantly higher in treated groups than that of control in NZW rabbits. Treatment of a water-soluble. Sal B-enriched fraction (SM-EW-1) of SM reduced atherosclerotic lesions in NZW rabbits and apoE(-) mice. Inhibition of atherosclerosis by SM relied heavily on the antioxidant effect. SM had an endothelial protective effect in rabbit model. This study concludes that SM, which contains Sal B as a major water- soluble antioxidant, increases <-tocopherol content in LDL, prevents LDL oxidation in vitro and ex vivo, and reduces atherosclerosis in these two atherosclerotic animal models.