Anti-diabetic, Antioxidant, and Toxicity Studies of Grewia abutilifolia Leaves Extracts

Abstract

Various species of the genus Grewia are reported as glucose lowering agent besides other diverse pharmacological activity in ethno medicinal as well as in scientific studies. The present study pursues investigation on the in-vitro anti-diabetic, antioxidant, and cytotoxicity studies of the aqueous-alcoholic and ethyl acetate extract of Grewia abutilifolia leaves. Free radical scavenging activities of the G. abutilifolia were assessed by the 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay. The toxicity of extracts was evaluated through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on HepG2 cells, while neurotoxic effects were evaluated by the functional observational battery. Anti-diabetic potential of the extracts was assessed via four in-vitro tests; α-glucosidase inhibitory activity,  α-amylase activity, glucose uptake in skeletal muscle cells 6-NBDG (6-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose) and GLUT4 uptake activity. In the DPPH assay, extracts showed concentration-dependent antioxidant effects. Ethyl acetate extracts displayed more antioxidant activity compared to aqueous alcoholic extract. Plant extracts did not exhibit any significant cytotoxic effect on the tested cells. Also, the extracts did not inhibit cell proliferation at lower concentration and showed mild anti-proliferative effect at very higher concentration having IC50 values 16 mg/mL and 35.28 mg/mL for aqueous-alcoholic and ethyl acetate extract, respectively. The extracts showed moderate to good anti-diabetic potential based upon the results of the glucosidase, α-amylase activity, glucose uptake and GLUT4 assays. Based upon the outcome of the study, G. abutilifolia was found to possess good anti-diabetic and antioxidant potential without any significant toxic effects. Plant can be explored further for its pharmaceutical applications.