Epithelial cell density in cataractous lenses of patients with diabetes: Association with erythrocyte aldose reductase

In the present study we evaluated the cell density of lens epithelium and its relation to the degree of erythrocyte aldose reductase (AR) in patients with type 2 diabetes. This prospective clinical study included 46 eyes of patients with type 2 diabetes and 48 eyes of patients without diabetes mellitus (DM). Flat preparations of lens epithelial cells (LECs) attached to the anterior capsule were studied. Multiple regression analysis was performed to evaluate the association between lens cell density and age, gender, type of cataract, duration of diabetes, diabetic retinopathy (DR), the levels of glycosylated hemoglobin (HbA1c) and erythrocyte AR. The mean density of LECs of patients with type 2 diabetes was 4141 ± 508 cells/mm2, which was significantly lower than that of patients without DM (4560 ± 458 cells/mm2; p < 0.0001). Multiple regression analysis revealed that the level of erythrocyte AR was correlated with the reduction of LECs in the eyes of patients with type 2 diabetes. The correlation between the density of LECs and the amount of erythrocyte AR was significant in the diabetic group with a high value of HbA1c (>6.5%) or with DR. These results suggest that the polyol pathway via AR may be associated with the reduction of epithelial cell density in the eyes of patients with DM.