Vernonia amygdalina stimulates muscle glucose uptake and modulates redox activities and functional chemistry in oxidative hepatic injury.

The ethyl acetate, ethanol, and aqueous extracts sequentially obtained from the leaves of Vernonia amygdalina were investigated for their antidiabetic and antioxidant protective effect in oxidative hepatic injury. The extracts showed significant (p < .05) free radical scavenging and reducing power activities. They significantly (p < .05) elevated reduced glutathione level, superoxide dismutase, and catalase activities, with concomitant depletion of malondialdehyde level. The ethanol and aqueous extracts caused a removal of oxidative-included chemical functional group at 1,500-1,200 (amide II)/cm region, with the inclusion of a functional group at 3,000-2,800 (carboxylic acid)/cm region. The extracts significantly (p < .05) inhibited the activities of α-glucosidase and α-amylase and stimulated glucose uptake in rat muscles. Gas chromatography-mass spectrometric (GC-MS) analysis revealed phytol as the predominant compound, with ethanol having the highest concentration. Based on the IC50 values, the ethanol extract exhibited the best activities, followed by the ethyl acetate extract, while the aqueous extract was the least. These results suggest the antioxidative and antidiabetic properties of V. amygdalina as evident by their modulation of antioxidant biomarkers and oxidative-induced chemistry changes and stimulate muscle glucose uptake. PRACTICAL APPLICATIONS: Vernonia amygdalina (bitter leaf) is amongst the common leafy vegetables in West Africa reported for its various medicinal and nutritional properties. It is utilized as a food ingredient as well as supplement for the treatment and management of type 2 diabetes. The ability of its extracts to stimulate glucose uptake and protect against diabetic-induced changes in the chemical functional groups of the liver gives more credence to its reported antidiabetic properties. Being a common leafy vegetable, V. amygdalina can be a cheap source of nutraceutical for the treatment and management of type 2 diabetes and its complications.