In vivo antidiabetic and antioxidant activities of chloroform fraction of Nelsonia canescens Leaf in Alloxan-induced Diabetic Rats

Abstract

Background: Diabetes mellitus, a metabolic disorder is responsible for the death of millions ofpeople across the globe. Poor efficacy, high cost and adverse side effects associated withavailable synthetic anti-diabetic drugs have necessitate the need to search for anti-diabetic drugsof natural origin. Therefore, in this study, the in vitro anti-diabetic and antioxidant activities ofchloroform fraction of Nelsonia canescens were evaluated.Methodology: Phytochemical composition, in vitro antioxidant and in vivo antidiabetic activityof the fraction were evaluated following standard protocols. Hyperglycemia was induced viaintraperitoneal injection of 90 mg/kgbwt of alloxan monohydrate. Male Wister rats weighingbetween 120.20±15.25 g were randomly distributed into five groups consisting of five rats eachand administered 50, 150 and 300 mg/kgbwt of the fraction, 5 mg/kgbwt of glibenclamide, and 2mL/kgbwt of normal saline respectively.Results: The quantitative phytochemical screening revealed the presence of phytochemicals(mg/100g) such as phenols (1624 ± 1.12), flavonoids (994.18 ± 1.26), tannins (75.71 ± 0.21),saponins (1038.40 ± 2.00) and alkaloids (88.59 ± 1.84). The fraction exhibited antioxidantactivity in a concentration-dependent manner with percentage inhibition of 68.20% at 100 μg/mLagainst DPPH radicals compared with ascorbic acid (89.28%). At 300 mg/kgbwt the fractionreduced the blood glucose concentration of rats to 119.00±2.70 mg/dL compared with70.50±5.50 for the glibenclamide treated group after 21st day. The fraction administrationresulted in lowered levels of total cholesterol, LDL-cholesterol and triglycerides and increasedlevel of HDL-cholesterol. There was a significant increase (p<0.05) at 300 mg/kgbwt in thelevels of catalase (33.36±0.36 U/mL), superoxide dismutase (71.66±0.56 U/mL) and reducedglutathione (100.64±3.25 μg/mL) activities compared with 26.86±0.76 U/mL, 33.32±0.73 U/mLand 63.82±2.10 μg/mL respectively for the control groups.