rhodanine and Cataract

Topics: Aldehyde Reductase; Animals; Binding Sites; Blood Glucose; Cataract; Chemical Phenomena; Chemistry; Corneal Diseases; Diabetes Complications; Diabetes Mellitus; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Disease Models, Animal; Fluorenes; Galactose; Humans; Hydantoins; Imidazoles; Imidazolidines; Models, Molecular; Naphthalenes; Phthalazines; Rhodanine; Sorbitol; Structure-Activity Relationship; Substrate Specificity; Sugar Alcohol Dehydrogenases; Thiazolidines; Tissue Distribution

Epalrestat is the unique aldose reductase inhibitor on the market, which was mainly used for the diabetic neuropathy. Lenses osmotic expansion could be induced by galactose to mimic the pathological process of diabetic cataract in vitro. In present study, we mainly investigated whether epalrestat possesses inhibitory effect on the lens osmotic expansion. The results indicated that epalrestat could not only markedly inhibit rat lens osmotic expansion in vitro, but also significantly reduced the high expression of the osmotic expansion-related genes such as AR and AQP1 in mRNA and protein levels. The findings may provide an important reference to epalrestat in the clinical application for the treatment of diabetic cataract.

Topics: Aldehyde Reductase; Animals; Aquaporin 1; Cataract; Diabetes Mellitus, Experimental; Enzyme Inhibitors; Galactose; Lens, Crystalline; Male; Osmosis; Rats; Rats, Sprague-Dawley; Rhodanine; RNA, Messenger; Thiazolidines

Properties and efficacies of novel aldose reductase (AR) inhibitors, M16209 (1-(3-bromobenzo[b]furan-2-ylsulfonyl)hydantoin) and M16287 (1-(3-chlorobenzo[b]furan-2-ylsulfonyl)hydantoin), were examined in vitro and in vivo, compared with known AR inhibitors, ONO-2235 and sorbinil. These four compounds inhibited partially purified aldose reductases from various origins, and the potencies of M16209 and M16287 were on the whole similar to ONO-2235, and were greater than that of sorbinil. The IC50 values of the four AR inhibitors did not substantially depend on the substrate used. Kinetic studies of inhibition of partially purified bovine lens (BLAR) revealed that M16209, M16287 and sorbinil were uncompetitive with glyceraldehyde and noncompetitive with nicotineamide adenine dinucleotide phosphate (NADPH), whereas ONO-2235 was noncompetitive with both glyceraldehyde and NADPH. Aldose reductase became less sensitive to the four inhibitors as enzyme purification progressed, although the susceptibility to inhibition was partially reversed by incubation with dithiothreitol. In addition, the four compounds slightly affected those enzymes of carbohydrate and glutathione metabolism which were tested. M16209 and M16287 prevented sorbitol accumulation in isolated rat tissues as potently as ONO-2235 and sorbinil. M16209 and M16287 were effective in the prevention of galactosemic cataracts and amelioration of diabetic neuropathy with almost the same potency, while ONO-2235 was effective only in neuropathy, and sorbinil was effective in galactosemic cataracts and diabetic neuropathy with a different potency. These results indicate that M16209 and M16287 are potent aldose reductase inhibitors, which could be applicable to treatment for diabetic complications.

Topics: Aldehyde Reductase; Animals; Benzofurans; Cataract; Cattle; Diabetic Neuropathies; Hydantoins; Imidazoles; Imidazolidines; In Vitro Techniques; Male; Rats; Rats, Inbred Strains; Rhodanine; Sorbitol; Thiazolidines