Phytoconstituents and Antidiabetic Activity of Vernonia amygdalina (Asteraceae) in Steptozotocin-induced Diabetic Rats (Published)
Vernonia amygdalina (VAM) is a medicinal plant that has been use traditionally in the management of diseases especially diabetes. Phytochemical screening and GC-MS analysis were carried out while 25 male albino wistar rats (137-223 g) were used to evaluate the andiabetic activity. The animals were randomly divided into five groups (n=5). Group I (control) received normal feed and water, while Groups II, III, IV and V were diabetes induced with single dose of 45 mg/kg b.wt streptozotocin (STZ) intraperitoneally. After three days, group III was treated with metformin (MET) whereas, groups IV and V were treated with 150 and 300 mg/kg b.wt VAM respectively for another seven days. Phytochemical screening showed the presence of most common phytochemicals except anthraquinone and GC-MS analysis revealed the presence of 10 phytoconstituents majorly fatty acids and esters, and phytol. The FBG levels of diabetic-induced rats treated with doses of VAM and MET were significantly reduced (p<0.05). There was observed significant (p<0.05) decrease in the levels of plasma aspartate aminotransaminase (AST, γ-glutamyl transferase (GGT) and lactate dehydrogenase (LDH), and non-significant (p>0.05) decrease in alanine aminotransaminase (ALT) in diabetic induced rats compared to control. MET treatment reversed the order in GGT and LDH while VAM doses could only reverse the order in LDH. At high dose, VAM significantly (p<0.05) increased the concentration of plasma total protein (TTP), creatinine (CRE), bilirubin (BIL) whereas, at low dose, VAM significantly (p<0.05) increased the concentration of plasma triglyceride (TRIG) and cholesterol (CHOL) compared to the STZ and control groups. In conclusion, this study suggests that VAM leaf extract possess some phytoconstituents which could be responsible for its antidiabetic activity.
Keywords: GC-MS, Rats, antidiabetic, streptozotocin, vernonia amygdalina