Therapeutic effect of resveratrol on diabetic cataract in rats

Objective To investigate the therapeutic effect of resveratrol on diabetic cataract in SD rats. Methods Forty-five SD rats(weighted (300±5) g) were randomly divided by using random number table into normal control group, diabetic model group and resveratrol group, 15 in each group. Diabetic cataract was induced by streptozotocin(STZ) in diabetic model group and resveratrol group. No treatment was given to the rats in normal control group, diabetic model group. The 400 mg/kg resveratrol was administrated by gavage in resveratrol group. At the end of 4, 8 and 12 weeks after the treatment of resveratrol, eyeballs were harvested and cataract formation in all rats was recorded, meanwhile the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and the level of malondialdehyde(MDA) in lenses were measured respectively. And the apoptosis of lens epithelial cells was detected and statisticed using terminal deoxynucleotidy transferase mediated x-dutpnik end labeling(TUNEL) method. Data were compared between groups by using t test. Results At the end of 4, 8 and 12 weeks, lens of normal control group were transparent, lens opacity in resveratrol group was higher than those in control group, but was lower than those in diabetic model group. At the end of 4, 8 and 12 weeks, the grey value of lens in resveratrol group was 27.5±2.2, 34.4±1.8, 46.4±5.1 respectively, and were all significantly lower than those in diabetic model group(t=24.063, 53.411, 54.027, all P<0.05), but were all markablly higher than those in control group(t=-8.902, -31.567, -44.013, all P<0.05). At the above-mentioned time points, the activity of SOD and GSH-Px were botn significantly higher than those in diabetic model group(t=-145.738--18.193, all P<0.05), but lower than those in control group(t=11.388-95.746, all P<0.05); the activity of MDA was lower than those in diabetic model group(t=33.027, 29.623, 40.976, all P<0.05), but higher than those in control group (t=-14.920, -22.851, -39.992, all P<0.05). At the end of 4, 8 and 12 weeks, the apoptosis rate of lens epithelial cells in resveratrol group were 0.66±0.17, 17.89±0.24, 28.21±0.38, respectively, which were higher than those in control group(t=-25.958, -77.897, -80.725, all P<0.05), but obviously lower in diabetic group(t=101.729, 45.940, 167.104, all P<0.05). Conclusion Resveratrol could increase the antioxidase activity, and inhibit the apoptosis of lens epithelial cells in diabetic cataract rats, thus delays the generation and development of catarac. Key words: Diabetic cataract; Resveratrol; Rats; Oxidative damage; Apoptosis