Profile of aldose reductase inhibition, anti-cataract and free radical scavenging activity of selected medicinal plants: An attempt to standardize the botanicals for amelioration of diabetes complications

Phytotherapy has played an important role in the management of diabetes and related complications. In the present study different fractions of Catharanthus roseus L. (Apocynaceae), Ocimum sanctum L. (Labiatae), Tinospora cordifolia Willd. (Menispermaceae), Aegle marmelos L. (Rutaceae), Ficus golmerata L. (Moraceae), Psoralea corlifolia L. (Fabaceae), Tribulus terrestris L. (Zygophyllaceae), and Morinda cetrifolia L. (Rubiaceae) were evaluated as possible inhibitors of aldose reductase (AR: a key enzyme implicated in cataractogenesis) and antioxidant agents. Anti-cataract activity of the selected plants was demonstrated using 'sugar induced lens opacity model' and the cytotoxicity studies were carried out using MTT assay. Among the tested plants, water extract of M. cetrifolia (IC50 0.132 mg/ml) exhibited maximum AR inhibitory activity as compared to other phytofractions which showed the activity in an IC50 range of 0.176-0.0.82 mg/ml. All the plant fractions showed considerable antioxidant potential. Sugar induced lens opacity studies revealed that, M. cetrifolia possess significant anti-cataract potential to maintain lens opacity as compared to glucose induced lens opacity in bovine lens model. The extract of the selected plants showed moderate cytotoxicity against HeLa cell line. Results of the present studies may find useful in converting botanicals into therapeutic modalities.

Highlights► Eight selected botanicals were evaluated in vitro for potential antidiabetic and antioxidant activities. ► The selected plant possesses significant free radical scavenging activities and antioxidant ingredients like vitamin C, flavonoids and phenolics. ► The Morinda citrifolia and Tinospora cordifolia showed significant rat lens aldose reductase (RLAR) inhibitory activity. ► The extracts of M. citrifolia and T. cordifolia showed impressive anti-cataract activity in the glucose induced bovine lens model. ► The water extract of T. cordifolia, Catharanthus roseus and M. cetrifolia were found cytotoxic against HeLa cell line.