Expression of miR-34a in cataract rats and its related mechanism.

Expression of miR-34a in cataract rats and its related mechanism were investigated. A total of 30 SD rats were selected and divided into three groups: group A: 2-month-old lucent lens, group B: 18-month-old lucent lens, and group C: 18-month-old naturally occurring cataract lens. The lens was taken and measured by LOC III to determine the degree of lens opacity of the three groups of rats. qPCR was used to detect expression of miR-34a and mRNA of SIRT1 and P53. Western blotting was used to detect the protein expression of SIRT1 and P53. Cell apoptosis was detected by flow cytometry. The lens of rats in group C was more turbid than that of groups A and B (P<0.05). The expression levels of miR-34a and P53 mRNA in the rats lens of group C were significantly higher than those in groups A and B, and the expression of SIRT1 mRNA was significantly lower than that of groups A and group B (P<0.05). Expression of miR-34a in group A was significantly higher than that in group B, the mRNA expression of SIRT1 was significantly lower than that in the lucent lens of 18-month-old rats (P<0.05). The expression of SIRT1 protein in group C was significantly lower than that in groups A and group B, while the expression level of P53 protein in group C was significantly higher than that of groups A and B. The expression of SIRT1 protein in group B was significantly higher than that in group A (P<0.05). The apoptosis rate of group C was higher than that of groups A and group B (P<0.05). In conclusion, the upregulation of expression level of miR-34a is related to cataract occurrence in rats, which may be caused by regulation of SIRT1 protein.