Experimental Study On LA In Protection Of Hydrogen Peroxide Induced Cataract Formation Of Rat's Lens

PARTâ… Experimental Study of the Inhibition ofα-Lipoic Acid against Hydrogen Peroxide-induced Rat Lens Epithelial Cell ApoptosisObjective:To observe the inhibitory effect ofα-lipoic acid(LA) against hydrogen peroxide-induced rat lens epithelial cell(LECs) apoptosis,and to investigate the correlation between LECs and lens opacity.Methods:Cultured normal rats' lenses in vitro were randomly divided into 5 groups:the control group,the group treated by hydrogen peroxide(H₂O₂)(200μmol/L),the group treated by H₂O₂ and LA(â… 0.5mmol/L,â…¡1.0mmol/L,â…¢2.0mmol/L).After 24 hours of incubation,the alteration of opacity of lenses were observed by photography and were determined image analysis,the rate of rat's LECs apoptosis was examined by terminal deoxyribonucleotide transferasemediate dUTP nick end labeling(TUNEL) detection.Result:1.All of the lens in the control group were remained transparent,but the lens in the group treated by H₂O₂ were found opacity. The transparence of the group treated by LA was higher than that of the group treated by H₂O₂ and lower than that of the control group,the differences of gray value among the groups were statistically significant (P＜0.05),2.The apoptosis rate for LECs in control group was 5.30%,the group treated by H₂O₂ was 85.94%,the group treated by LA were 69.43%, 37.74%,48.61%seperately.The H₂O₂ group was apparently higher than that of the control group(P＜0.05),and there were significant differences between the LA groups and the H₂O₂ group(P＜0.05).Conclusion:1.The model of oxidative cataract could be made successfully by H₂O₂ in animals.2.The apoptosis of LECs could be induced by H₂O₂.3.The antioxidant-LA can evidently inhibit the rats cataracat information and reduce the LECs apoptosis induced by H₂O₂.PARTâ…¡Experimental Study of the Inhibition of LA against Hydrogen Peroxide-induced Rat Lens of Biochemical MetabolismObjective:To observe the inhibitory effect of LA against hydrogen peroxide-induced rat lens of biochemical metabolism,and to investigate the correlation between lens opacity and lens biochemical indexes.Methods:Cultured normal rats' lenses in vitro were randomly divided into 5 groups:the control group,the group treated by H₂O₂(200μmol/L), the group treated by H₂O₂ and LA(â… 0.5mmol/L,â…¡1.0mmol/L,â…¢2.0mmol/L).After 24 hours of incubation,the lense were examined for biochemical parameter such as malondialdehyde(MDA),glutathione peroxidase(GSH-Px),lactate dehydrogenase(LDH) and superoxide dismutase(SOD) by spectrophoto metrically.Result:1.The level of SOD,GSH-Px,LDH,MDA in each group were:the control group:1.88±0.05,784.98±54.67,1965.21±97.83, 0.023±0.0051;the group treated by H₂O₂:0.91±0.04,263.25±30.57, 1192.62±80.62,0.153±0.1120;the group of LAI:1.03±0.08 482.76±37.03,1251.61±104.3,0.109±0.0074,the group of LAâ…¡:1.67±0.08,674.29±66.14,1746.53±93.65,0.044±0.0860,the group of LAâ…¢:1.26±0.10,563.33±42.48,1544.37±65.37,0.063±0.1140. 2.The level of MDA was increased and levels of GSH-Px,SOD,LDH were decreased significantly in H₂O₂ group compared with those of them in control group(P＜0.05),the level of MDA was significantly decreased but the levels of other indexes were increased in LA groups compared with those of them in H₂O₂ group(P＜0.05).Conclusion:The antioxidant-LA can evidently inhibit the rats cataracat information by increasing the activity of antioxidant enzyme in lens.