Abstract
Purpose :
Diabetic retinopathy is a serious sight-threatening complication of diabetes. In the current research, we explored the effect and possible mechanism of the DNA methylation inhibitor-zebularine on diabetic retinopathy in a Rats mode induced by STZ
Methods :
The model of SD diabetic rats was induced by streptozotocin. The 48 male SD rats were divided into 6 groups: normal control group,STZ diabetic rats group,zebularine 100uM group,zebularine 200uM group,zebularine 400uM group and anti-vegf group，8 rats in each group. The Transmission Electron Microscope was used and HE staining to observe the morphology of each retina. Using immunofluorescence to probe the degree of DNA methylation in each group, mRNA expression was measured by real-time PCR (RT-PCR).DNA methylation in the promotor of ppar-γ was measured by the sodium bisulfite sequencing method . SPSS software was employed to make the statistical analysis of experimental results. We used One-way ANOVA to compare data between two groups and P<0.05 was considered to be statistically significant.
Results :
TEM: DR rats’ microscopic structures were destroyed. Well in the zebularine group, the microscopic structure was better than the STZ group.HE: in the STZ group, the microscopic structures were changed, but zebularine ameliorated the changes.Immunofluorescence: compared to the normal group， the expression of mecp2 and 5-mC in the STZ-induced diabetic rats group was increased significantly, and the methylation inhibitor-zebularine can reduce the expression of the two proteins.Real-time fluorescence quantitative - PCR: in the STZ group, the mRNA expression of vegfa, txnip, snail1, and N-cadherin was significantly elevated (p<0.05), and in the zebularine group, the expression of these genes was decreased obviously (p<0.05). In the STZ group, the expression of sirt1 and PPAR-γ was significantly lower than normal group (p<0.05), and in the zebularine group, sirt1 and ppar-γ’s expression was increased (p<0.05). Sodium bisulfite sequencing: Zebularine reduced the methylation level of CpG island in the PPAR-promoter region in diabetic rats (p<0.05)
Conclusions :
Zebularine can ameliorate the morphological changes caused by diabetic retinopathy.Zebularine can reduce the methylation level of CpG island in the PPAR-γpromoter region in diabetic rats, suggesting that zebularine is a potential treatment for diabetic retinopathy by decreasing the methylation level.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.