Title:Anti-Diabetic Effect of a Flavonoid and Sitosterol - Rich Aqueous Extract of Pleurotus tuberregium Sclerotia in Alloxan-Induced Diabetic Rabbits
Volume: 19
Issue: 8
Author(s): Ifeanacho Mercy Onuekwuzu, Ikewuchi Catherine Chidinma and Ikewuchi Jude Chigozie*
Affiliation:
- Department of Biochemistry, Faculty of Science, University of Port Harcourt, Port Harcourt,Nigeria
Keywords:
Atherogenic indices, diabetes mellitus, isoquercetin, lipid profile, luteolin, phytosterols, Pleurotus tuberregium.
Abstract:
Objective: Traditionally prepared infusions and decoctions are commonly used in the management
of diabetes mellitus, in southern Nigeria; one of such is the aqueous extract of the sclerotia of
Pleurotus tuberregium (“usu” milk). In this study, the effects of the extract on the body weights, tissue/
organ weights, fasting blood glucose, blood/plasma lipid profiles and atherogenic indices were
investigated in normal and alloxan-induced diabetic rabbits.
Methods: Diabetes mellitus was induced by the injection of alloxan (120 mg/kg body weight) via the
marginal ear vein. The extract was administered orally at 100, 200 and 300 mg/kg to normal and diabetic
rabbits; while metformin was administered at 50 mg/kg. The crude extract was analyzed by gas
chromatography, coupled to flame ionization detector.
Results: Thirty-one known flavonoids were detected, consisting mainly of isoquercetin (28.5%), luteolin
(24.3%), quercetin (18.8%) and kaempferol (11.3%). Sitosterol (82.0%) and stigmasterol (12.5%)
were the most abundant of the seven phytosterols detected. Compared to the diabetic control, the
treatment significantly (p<0.05) lowered the weights of the kidney and liver, as well as the levels of
blood glucose and triglyceride, plasma VLDL, LDL and non-HDL cholesterol, atherogenic index of
plasma, cardiac risk ratio, atherogenic coefficient and Castelli’s risk index II. It, however, significantly
(p<0.05) increased plasma HDL cholesterol, without significantly affecting blood total cholesterol
levels.
Conclusion: This study showed that the extract was hypoglycemic, and improved lipid profile and
atherogenic indices, thus highlighting its cardioprotective potential, thereby supporting its use in the
management of diabetes mellitus.