Hypolipidemic and antioxidant effect of Ajuga iva in rats fed a high-cholesterol diet

Ajuga iva (L.) Schreb. has been reported to have a variety of biological effects including hypoglycemic, vasorelaxant, hypolipidemic, antiinflammatory, antifungal, antimicrobial and anthelmintic activity [1, 2]. The present study explores the possible antioxidant and hypolipidemic effects of the aqueous extract of Ajuga iva (Ai 0.5% in the diet) in rats fed a high-cholesterol (1%) diet (HCD). The results indicated that the HCD-Ai vs. HCD treatment led to many changes in biochemical parameters. They showed a decrease by 18% of plasma total cholesterol (TC) and by 29% VLDL-cholesterol but an increase by about 35% of HDL₂-cholesterol. The triacylglycerol contents were reduced by 31% in plasma and 74% in VLDL. The lipid peroxidation determined by TBARS was decreased by 75% in plasma. TBARS in liver, heart and kidneys were highly reduced excepted in the adipose tissue. A.i. treatment enhanced superoxide dismutase activity in liver and kidney. Glutathione reductase activity was lowered in adipose tissue but increased in liver and in kidney. A significant increase was noted in glutathione peroxidase activity in liver, heart and kidney but a low value in adipose tissue was observed. In conclusion, this study demonstrates that in addition to its potent TG and TC-lowering effects, Ai is effective in improving the antioxidant status by reducing lipid peroxidation in plasma and tissues and enhancing the antioxidant enzymes in HCD fed rats. A phytochemical screening indicated the presence of flavonoids and terpenoids. Their isolation and characterization are currently in progress.

References: 1. El Hilaly, J. et al. (2006), J. Ethnopharmacol. 105: 441–448. 2. Bondi, M.L. et al. (2000) Biochem. Syst. Ecol. 28: 1023–1025.