Fig 1: DNMT1-mediated DNA methylation was significantly increased in the early phase of diabetic retinopathy. (a) STZ injection upregulated the global DNA methylation level of the retina until 6 weeks after injection. (b) Quantification of the average 5-mC content in DNA methylation of the retina isolated from sodium citrate buffer injection (control) and STZ injection (STZ) groups. (c–d) Western blot showed the protein expression levels of DNMT1, DNMT3A, and DNMT3B. *P < 0.05, **P < 0.01.