Water leaves extracts of Cornus mas and Cornus kousa as aldose reductase inhibitors: the potential therapeutic agents

The Cornaceae family is mainly known for the research connected with its fruits and flowers, but the biological activities of leaves of Cornus species are not very intensively studied. Present work is focused on inhibition of rat lens aldose reductase, cytotoxicity, and study of oxidant efficacy on NIH-3T3 cells of the water extracts of the leaves of Cornus mas and Cornus kousa. The obtained results showed effective inhibition of isolated rat lens aldose reductase in low A mu g/mL level, antioxidant properties at lower concentration (50 A mu g/mL), and slight prooxidant properties at higher concentration (100 A mu g/mL). The prooxidant properties could contribute to cytotoxicity when the cells incubated with the extracts of concentration 100 A mu g/mL reduced 10% of MTT of control cells. The biological activities of two Cornus species were quite similar in all our tests. Low concentrations of both water leaves extracts could be perspective agents for potential treatment of chronic diabetic complications, inflammation, and another diseases connected with aldose reductase enzyme.