Investigation of MicroRNA Expression in Anterior Lens Capsules of Senile Cataract Patients and MicroRNA Differences According to the Cataract Type

PURPOSE: We investigated the microRNAs (miRNAs) expression in the anterior lens capsules of patients with senile cataract and compared it to that in the anterior lens capsules of healthy controls. Moreover, we compared the differences in miRNAs expression according to the types of cataracts. METHODS: Individual lens epithelium samples were collected from 33 senile patients and 10 controls. The cataract patients were classified into cortical, nuclear, posterior and anterior subcapsular and mixed. The expression of 12 different miRNAs in lens epithelium was measured using real-time polymerase chain reaction and compared between the senile cataract patients and controls. The differences of miRNA levels according to cataract type were analyzed. RESULTS: The expression levels of let-7g-5p, miR-23a-3p, miR-23b-3p, and miR-125a-5p were significantly upregulated in patients with senile cataract when compared with those in the control group (P < 0.05). The expressions of let-7a-5p, let-7d-5p, miR-16-5p and miR-22-3p were significantly downregulated in the senile cataracts (P < 0.05). Let-7a-5p, let-7d-5p, let-7g-5p and mir-23b-3p had significant difference in expression between nuclear and anterior subcapsular cataracts. CONCLUSIONS: The eight differentially expressed miRNAs may be involved in the pathogenesis of senile cataract, in particular, related to oxidative stress and autophagy. TRANSLATIONAL RELEVANCE: We infer that several miRNAs in lens epithelial cells are promising candidate biomarkers of senile cataracts.