Evaluation of in vitro cytoprotective and antioxidant effects of Tinospora cordifolia in cultured HepG2 cells

Abstract

IntroductionTinospora cordifolia is a popular medicinal plant containing a variety of phytochemicals including flavonoids, alkaloids, tannins, saponins and polyphenols, which have shown various pharmacological activities. The present study is aimed at comparing the cytoprotective and antioxidant potential of aqueous, ethanolic and methanolic extracts of T. cordifolia stem, in HepG2 cells cultured in Dulbecco’s Modified Eagle Medium (DMEM) supplemented with high concentrations of glucose and fructose, both alone and in combination, to mimic diabetic conditions. MethodsThe antioxidant potential and free radical scavenging properties of extracts of T. cordifolia were measured by DPPH and ferric ion reducing power (FRAP) assays. The cytoprotective potential of extracts against HepG2 cells cultured in DMEM supplemented with 5 mM, 10 mM and 50 mM of glucose, 1 mM, 5 mM and 20 mM of fructose and their combinations, was measured by MTT and SRB assays and also lactate dehydrogenase release in the culture medium, while the antioxidant potential was evaluated by measuring decrease in oxidative damage of lipids and proteins. ResultsVarious extracts of T. cordifolia, viz., aqueous, ethanolic and methanolic, show free radical scavenging properties, thus are also effective in increasing the viability of cells which was decreased by supplementation of excess sugars in the medium. Treatment of extracts also reduced the levels of damaged lipids and proteins in HepG2 cells. ConclusionsThe results indicated that the naturally occurring phytoconstituents of T. cordifolia stem are potentially cytoprotective and antioxidant. Furthermore, the constituents show potential in reversing the diabetes-induced changes in HepG2 cells, thus improving their survival and functional integrity.