Aldose reductase inhibitors and diabetic complications.

Aldose reductase inhibitors impede flux of glucose through the sorbitol pathway in diabetes mellitus. They therefore reduce the accumulation of the pathway metabolites, sorbitol and fructose, reduce the impact of the flux on the cofactors used by the pathway and reduce other derived phenomena, such as osmotic stress and myo-inositol depletion. As drugs, their targets are the chronic complications of diabetes--neuropathy, retinopathy, nephropathy and vasculopathy. In experimental models there is proof of activity against biochemical, functional and structural defects in all of the involved tissues, but we await full clinical verification of this potential.