Changes in apoptosis factors in lens epithelial cells of cataract patients with diabetes mellitus.

PURPOSE: To determine and compare the expression of apoptotic factors Bax and Bcl-2 in lens epithelial cells (LECs) of cataract patients with and without diabetic retinopathy (DR), the duration of diabetes mellitus (DM), and the glycated hemoglobin (HbA1c) level.

SETTING

St. Mary's Hospital, The Catholic University of Korea, Seoul, South Korea.

DESIGN

Randomized prospective study.

METHODS

Patients were classified into 3 groups as follows: patients without DM (Group 1), patients with DM but without DR (Group 2), and diabetic patients with DR (Group 3). Data on the duration of DM and the HbA1c levels were recorded. The anterior capsule was obtained from the patients after cataract surgery, and immunohistochemical stains of Bax and Bcl-2 were performed. The stained anterior capsules were analyzed by reactivity scoring.

RESULTS

Each group comprised 20 eyes. There was a statistically significant increase in Bax expression in all groups (P<.001). The Bcl-2 expression increased more in Group 2 and Group 3 than in Group 1, although the difference was not significant (P=.615). With a longer duration of DM and higher HbA1c level, Bax expression significantly increased but Bcl-2 was weakly expressed.

CONCLUSIONS

The apoptosis in LECs increased in cataract patients with DM and with or without DR. Using this knowledge on the regulation of apoptosis will permit better identification of the factors involved in the etiology of diabetes and may result in new therapies for diabetic cataract.

FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.