Dietary supplementation with Ethiopian pepper ( Xylopia aethiopica ) modulates angiotensin-I converting enzyme activity, antioxidant status and extenuates hypercholesterolemia in high cholesterol fed Wistar rats

The lipid lowering, antihypertensive, hepatoprotective and antioxidant activities of Ethiopian pepper (Xylopia aethiopica) supplemented diet in hypercholesterolemic rats were investigated in this study. Animals were divided into five groups (n = 7); normal control rats (NC); untreated hypercholeterolemic rats (Hyper-C diet); hypercholesterolemic rats treated with oral dose of 1 mg/kg of simvastatin (Hyper-C diet + STATIN); hypercholesterolemic rats treated with 2% (Hyper-C diet + 2%ETP) or 4% (Hyper-C diet + 4%ETP) supplementation of ETP. ETP-supplemented diets (2% and 4%ETP) reduced total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and concomitantly increased high-density lipoprotein (HDL). There was no significant difference between the TG and LDL levels of groups fed with Hyper-C diet + 4%ETP and Hyper-C diet + STATIN. Furthermore, Hyper-C diet + 4%ETP significantly reduced plasma angiotensin-I converting enzyme (ACE) levels compared to Hyper-C diet + 2%ETP and Hyper-C diet + STATIN. Furthermore, elevated serum levels of ALT, AST and ALP induced by the high cholesterol diet were reversed by ETP and STATIN supplemented diet. Rutin, quercetin and ellagic acid were the dominant phenolic compounds in ETP as revealed by high performance liquid chromatography analysis. The observed hypolipidemic, antihypertensive and hepatoprotective effects exhibited by ETP suggest its potentials to prevent lipid abnormalities and associated risk factors, and this could be attributed to its phenolic constituents.