Molecular Docking Analysis of Sorbitol Dehydrogenase Using Ligandfit Algorithm

Diabetic retinopathy is a major cause of visual impairment worldwide. The polyol pathway is a two step metabolic process in which the enzyme aldose reductase reduces glucose to sorbitol using NADPH as a cofactor; Sorbitol is then metabolized to fructose by sorbitol dehydrogenase (SORD) that uses NAD+ as cofactor. Human sorbitol dehydrogenase is a tetramer of identical, catalytically active sububits. Recent evidence suggests that the inhibition of both sorbitol and fructose is required to achieve beneficial effects in diabetic retinopathy. In our present study the molecular docking analysis of sorbitol dehydrogenase was carried out using Accelyr's Discovery studio software (uses LIGANDFIT algorithm). The binding affinity of several ligands to the target protein was calculated based on the dock scores obtained. It was found that out of 210 compounds 21 ligands docked to SORD whereas 17 ligands failed to dock and 59 ligands were found to be without hits. Among the 21 ligands, Dithiodialanine had greater binding affinity with the receptor thereby it can be recommended as a drug for the treatment of diabetic retinopathy.