Effects of Neem ( Azadirachta indica ) Leaf Extracts on Lipid and C-reactive Protein Concentrations in Cholesterol-fed Rats

Abstract

Objectives: Aim of this study is to investigate the effects of Neem ( Azadirachta indica ) leaf extract on serum lipid parameters and C-reactive protein (CRP) concentrations. The association between CRP and serum lipid profiles in hypercholesterolemic rats is also investigated. Methods: Total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), triglyceride (TG) and CRP were measured at week 0, 2, 4, 6 and 8 in 4 groups of animals; the control group (C), cholesterol control group (CC), cholesterol-fed groups treated with Neem leaf extract at doses of 50 and 300 mg/kg/day orally (N1&N2), respectively. Results: Cholesterol feeding had resulted in a significant increase (p<0.05) in TC, LDL&TG in group CC starting from week 2 and a decrease in HDL levels (p<0.05). CRP concentrations also showed a significant increment in the cholesterol-treated rats (CC) compared to group C, N1&N2 (p<0.05). Neem extract treated, TC, LDL and TG levels remained within the normal range similar to Group C and CRP concentrations were lowered but HDL levels were not. Conclusions: It is shown in this study that the concentrations of CRP had increased in CC rats but not in rats with normal cholesterol levels. Neem extract at 50 and 300 mg/kg doses had prevented the rise of TC, LDL and TG in cholesterol-fed rats. No significant changes in CRP concentrations were noted in the Neem-treated animals. Association between CRP and serum lipid concentrations is directly proportionate. They also suggest that Neem leaf extracts at 50 and 300 mg/kg concentrations are excellent lipid-lowering agent.