硫辛酸烟酸二联体对蓝光致大鼠视网膜损伤的防治作用OACSTPCD

·AIM:To investigate the preventive effect and optimal drug dose of lipoic acid-niacin(N2L)against blue light-induced retinal damage in SD rats,and to explore its possible protective mechanism. ·METHODS:A total of 36 specific pathogen free-grade male SD rats of 150-200 g were selected and randomly divided into normal control group,blue light injury group,N2L low-dose group(1.0 mg/kg),N2L medium-dose group(2.5 mg/kg),N2L high-dose group(5.0 mg/kg),and physiological saline group,with 6 rats in each group.The normal control group was reared in a 12 h dark and light cycle,and the rest of the groups received 9 h of daily light exposure,3 h of blue light irradiation with a wavelength of 455 nm and an intensity of 3000±50 Ix,and 12 h of darkness to establish the injury model,and were exposed to light exposure for 14 d.For 14 consecutive durations,a 1 mL dose of the corresponding drug was injected intraperitoneally.The rats were reared for another 5 d with a regular 12 h light-dark cycle and were examined by electroretinography.Specimens were prepared by over anesthesia,HE staining,and the thickness of the outer nuclear layer was observed under a optical microscope;superoxide dismutases(SOD)activity was detected by CheKineTM SOD Activity Assay Kit;and the retinal Caspase-3,quinone oxidoreductase 1(NQO1),glutathione S transferase(GST),Bcl-2,and Bax protein expression in rat retina were detected by Western blot. ·RESULTS:The amplitude of b-wave in dark-vision ERG 3.0 and 10.0(cd·s)/m2 stimulated light,b-wave in bright-vision ERG 3.0(cd.s)/m2 stimulated light,and the amplitude of the 2nd wave peak of oscillatory potential were significantly lower in blue light injury group than that in the normal control group(all P＜0.01),while the amplitude was significantly higher in the N2L medium-dose group than in the blue light injury group(all P＜0.05),and was not statistically different from that of the normal control group;the thickness of the retina in the blue light injury group was decreased in the ONL compared with that of the normal control group(P＜0.001),while in the N2L medium dose group,it was thicker than that of the blue light injury group(P＜0.001),and there was no statistically significant difference from the normal control group;SOD activity was significantly higher in the N2L medium-dose group than in the remaining 5 groups(P＜0.05);the expression of Caspase-3.Bax,and NQO1 in the blue light injury group was higher than that of the normal control group(all P＜0.01),and expression of Bax and Caspase-3 was significantly lower in the N2L medium-dose group compared with the blue light injury group(all P＜0.001),whereas GST,NQO1 and Bcl-2 were significantly increased(all P＜0.01). ·CONCLUSION:A concentration of 2.5 mg/kg N2L can effectively antagonize the damaging effect of blue light on the retina of SD rats,and it is expected to be a preventive and curative drug for it.