Effect Of Metformin On The Expression Of Cys C In Rats With Diabetic Retinopathy

Objective:To investigate the effect of metformin on the expression of Cyc C in rats with diabetic retinopathy.Methods: The rat DR model was established and divided into control group,model group and metformin group with 10 rats in each group.Metformin group was given metformin 300 mg/(kg ·d)by gastric perfusion for 2 months.At the same time,the rats in the control group and model group were given the same amount of 1% carboxymethylcellulose by intragastric administration for 2 months.The ultrastructure and histomorphology of retina were observed by transmission electron microscope and hematoxylin-eosin staining.The expression of Cys C in serum was measured by ELISA and the expression of Cyc C mRNA in retinal tissue was detected by qRT-PCR.Result:1.Transmission electron microscopy results showed that the thickness of the basal membrane of the control group was normal,the capillaries had no lesions,and the cell morphology was normal.In the model group,the basal membrane of the retina was significantly thickened,the capillary lesions were obvious,and the pericellular edema was observed.The retinal mitochondria of the metformin group were slightly swollen,and no significant changes were observed in vascular endothelial cells.2.HE staining results showed that the thickness of each layer of retina in the control group was normal,no dilatation of blood vessels was observed,and no abnormalities were observed in ganglion cells and kernel layer.In the model group,the thickness of each layer of retina increased,blood vessels dilated,ganglion cells and the inner layer of the nucleus showed obvious vacuolar degeneration.In the metformin group,the thickness of each layer of retina decreased and the retinal layer was arranged neatly.3.ELISA method results showed that compared with the control group,the serum Cys C level of rats in the model group was up-regulated.Compared with the model group,the serum Cys C level of rats in the metformin group was down-regulated,with statistically differences(P<0.01).4.qRT-PCR results showed that: compared with the control group,the expression of Cys C mRNA in the retinal tissues of the model group was up-regulated.Compared with the model group,the expression of Cys C mRNA in the retina of the metformin group was down-regulated,with statistically differences(P<0.05).Conclusion:Cys C is an important risk factor for the occurrence of DR.Metformin has a protective effect on DR,which is related to its down-regulation of Cys C.