Efficacy study of the bioactive fraction (F-3) of Acorus calamus in hyperlipidemia

Objective : To investigate the effect of the bioactive F-3 fraction from the rhizomes of Acorus calamus in experimentally induced hyperlipidemic rats. Materials and Methods : Doses of 10, 20 and 40 mg/kg of the bioactive fraction were evaluated for its effect on the lipid profile and fibrinogen levels in diet-induced hyperlipidemia. Additionally, apoprotein A1 and apoprotein B levels were estimated using immunoturbidimetric assays. Furthermore, the bioactive F-3 fraction was investigated for its mechanism of action by estimating HMG-CoA reductase activity and fecal cholesterol levels. Besides evaluating the free radical-scavenging activity using the Diphenyl picryl hydrazyl (DPPH) method, the high performance thin layer chromatography (HPTLC) fingerprint of the bioactive fraction was also developed. Results : At doses of 20 and 40 mg/kg, the bioactive fraction significantly (P < 0.05) decreased the total cholesterol (TC) and low-density lipoprotein (LDL) levels. The bioactive F-3 fraction also attenuated the raised plasma fibrinogen levels. Fecal cholesterol excretion was significantly (P < 0.05) enhanced by the F-3 fraction while 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA reductase) activity was depressed. Furthermore, the F-3 fraction also possessed an appreciable free radical scavenging activity. Conclusion : The results of the present study revealed that the bioactive F-3 fraction demonstrated its cholesterol-reducing effect by increasing fecal cholesterol excretion and decreasing cholesterol biosynthesis in the liver. Additionally, the effects on fibrinogen levels and free radicals indicate that the bioactive F-3 fraction could have a potentially beneficial effect in atherosclerosis associated with hyperlipidemia.