Severity of lens opacity, age, and correlation of the level of silent information regulator T1 expression in age-related cataract

Purpose: To evaluate the correlation between the severity of lens opacity, patient age, and the level of silent information regulator T1 (SirT1) expression in the lens epithelium of age-related cataracts. Setting: Department of Ophthalmology, Zuoying Armed Forces General Hospital, Kaohsiung, Taiwan. Design: Case control study. Methods: Patient age at the time of cataract surgery and lens opacity severity, classified using the modified version of the Lens Opacities Classification System III (LOCS III), were recorded. Lens epithelium samples were obtained, and the expression level of SirT1 mRNA was evaluated. Results: The study evaluated 233 eyes with cataract. Older patients had higher nuclear (N), cortical (C), and posterior subcapsular (P) cataract LOCS III scores. The expression of SirT1 in lens opacity was significantly less in patients 51 years and older than in those younger than 51 years. The level of SirT1 expression was significantly negatively associated with patient age (r = -0. 746, P<.001). A significant correlation was also found between a higher N, C, and P cataract score and lower expression of SirT1 in patients with age-related cataract (P<.001). Conclusions: The decreased expression of SirT1 in the lens epithelium was associated with higher cataract scores and patient age. The results suggest that a local SirT1 decrease in cataractous lens could be a risk factor for the initiation of age-related cataract formation.