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

Abstract

Diabetes mellitus, a metabolic disorder is responsible for the death of millions of people across the globe. Poor efficacy, high cost and adverse side effects associated with available synthetic anti-diabetic drugs have necessitate the need to search for anti-diabetic drugs of natural origin. Therefore, in this study, in vitro anti-diabetic and antioxidant activities of chloroform fraction of Nelsonia canescens were evaluated. Methodology: Phytochemical composition, in vitro antioxidant and in vivo antidiabetic activity of the fraction were evaluated following standard protocols. Hyperglycemia was induced via intraperitoneal injection of 90 mg/kgbwt of alloxan monohydrate. Male Wister rats weighing between 120.20 ± 15.25 g were randomly distributed into five groups consisting of five rats each and administered 50, 150 and 300 mg/kgbwt of the fraction, 5 mg/kgbwt of glibenclamide, and 2 mL/kgbwt of normal saline respectively. Results: The quantitative phytochemical screening revealed the presence of phytochemicals (mg/100 g) 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 antioxidant activity in a concentration-dependent manner with percentage inhibition of 68.20% at 100 μg/mL against DPPH radicals compared with ascorbic acid (89.28%). At 300 mg/kgbwt the fraction reduced the blood glucose concentration of rats to 119.00 ± 2.70 mg/dL compared with 70.50 ± 5.50 for the glibenclamide treated group after 21st day. The fraction administration resulted in lowered levels of total cholesterol, LDL-cholesterol and triglycerides and increased level of HDL-cholesterol. There was a significant increase ( p < 0.05) at 300 mg/kgbwt in the levels of catalase (33.36 ± 0.36 U/mL), superoxide dismutase (71.66 ± 0.56 U/mL) and reduced glutathione (100.64 ± 3.25 μg/mL) activities compared with 26.86 ± 0.76 U/mL, 33.32 ± 0.73 U/mL and 63.82 ± 2.10 μg/mL respectively for the control groups. Conclusion: The results of this study showed that chloroform fraction of N. canescens possess significant antioxi- dant and anti-diabetic activities.