Experimental Study Of The Effect Of The RLM On The Apoptosis Of Lens Epithelial Cells In The Diabetic Rat

Objective: To investigate the inhibition effect of the Rosa laevigata Michx(RLM) the rat lens epithelial cell(LECs) apoptosis induced by the diabetic rat, thus to provide basic methods and experimental basis for the mechanism of the diabetic cataract.Methods: 60 SD rats were randomly grouped into three: normal control, diabetic model and RLM. Diabetic cataract was induced by streptozotocin (STZ) intraperitonel injection (65mg/kg in 0.1 mol/L sodium cireate buffer). Lens were examined by slitlamp every four weeks. At the end of 4 weeks, 8 weeks, 12 weeks after STZ injection, eyeballs were isolated. Terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL) was used to analyze the lens epithelial cells apoptosis, immunohistochemical method to detect the expression of Bcl-2 and Bax, the expression level of Bcl-2 and Bax mRNA were detected by image analyse system and reverse transcription-polymerase chain reaction (RT-PCR) respectively.Result: 1,The opacity and apoptosis in rats RLM group were apparently lower than those in diabetic model group (P<0.05). 2,TUNEL detection discover,RLM group each timing apoptosis rate were decreased significantly in diabetic model group (P<0.05). 3,Bcl-2 and bax protein were expressed in LECs of normal; Expression of bcl-2 protein was much stronger than that of bax protein. The expression of bcl-2 protein was down-reguated and that of bax protein was up-regulated in the diabetic model group when compare with the normal group, so that the ratio of bcl-2/bax was lower; RML group up-regulated the expression of bcl-2 mRNA, and down-regulated the expression of bax mRNA, as the result, the ratio of bcl-2/bax was higher. There were marked differences in the range of ration changes compared to that of the diabetic model group(P<0.05). 4,The expression of bcl-2 mRNA was down-reguated and that of bax mRNA was up-regulated in the diabetic model group when compare with the normal group, so that the ratio of bcl-2/bax was lower; RML group up-regulated the expression of bcl-2 mRNA, and down-regulated the expression of bax mRNA, the ratio of bcl-2/bax was higher. There were marked differences in the range of ration changes compare with that of the diabetic model group(P<0.05).Conclusion: RLM could take an inhibitory role in STZ induced rat lens epithelial cells apoptosis and maybe have the effect to delay and ameliorate the occurrence and development of diabetic cataract.