RESUMEN
The present study explored the antihyperlipidemic potential of a standardized methanolic extract of Averrhoa carambola (A. carambola) leaf (MEACL) in high-fat diet (HFD)-fed rats. The standardized MEACL was orally administered at different doses (250, 500, and 1000 mg/kg) to HFD-induced hyperlipidemic rats for five weeks. Serum lipid profile, body weight changes, body mass index (BMI), daily food intake, relative organ weight, and histology of the liver were evaluated. In addition, the effect of MEACL on HMG-CoA reductase and pancreatic lipase activities as well as hepatic and fecal lipids was demonstrated. MEACL supplementation reduced serum lipids in HFD-fed rats in a dose-dependent manner. Histopathological scores revealed that 1000 mg/kg MEACL restored the damage to liver tissue in hyperlipidemic rats. MEACL decreased the body mass index (BMI), atherogenic index, and hepatic cholesterol and triglycerides and increased fecal cholesterol and bile acids in HFD-fed rats. Also, MEACL ameliorated lipid peroxidation and improved antioxidant defenses in the liver of HFD-fed rats. Furthermore, HMG-CoA reductase and lipase were suppressed by MEACL. In conclusion, this study shows the potential effect of MEACL to ameliorate hyperlipidemia and oxidative stress in HFD-fed rats. It prevented hepatic lipid accumulation and exerted an inhibitory effect on HMG-CoA reductase and lipase.
RESUMEN
BACKGROUND: Ethanolic extract of G. procumbens leaves has been previously shown to possess antihyperlipidemic effects. OBJECTIVE: This study was designed to prepare caffeoylquinic acids rich and poor fractions of the ethanolic extract using resin column technology and compare their antihyperlipidemic and antioxidant potentials. RESULTS: Among the treatment groups, caffeoylquinic acids rich fraction (F2) and chlorogenic acid (CA, one of the major caffeoylquinic acids) showed potent antihyperlipidemic effects, with significant reductions in total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C), very low-density lipoprotein-cholesterol (VLDL-C), atherogenic index (AI) and coronary risk index (CRI) (p<0.01 or better) compared to the hyperlipidemic control at the 58 h. The effect was better than that of ethanolic extract. In addition, only F2 significantly increased the high-density lipoproteincholesterol (HDL-C) level (p<0.05). F2 showed better effect than CA alone (60 mg) despite the fact that it only contained 9.81 mg CA/1000 mg dose. The findings suggest that the di-caffeoylquinic acids (86.61 mg/g dose) may also in part be responsible for the potent antihyperlipidemic effect shown by the F2. Likewise, F2 showed the highest antioxidant activity. Thus, simple fractionation of ethanolic extract using the Amberlite XAD-2 resin technique had successfully enriched the caffeoylquinic acids into F2 with improved antihyperlipidemic and antioxidant capacities than that of the ethanolic extract. CONCLUSION: The resin separation technology may find application in caffeoylquinic acids enrichment of plant extracts for pre-clinical studies. The F2 has potential for development into phytopharmaceuticals as adjunct therapy for management of hyperlipidemia.
