Higher Concentration of Transforming Growth Factor-beta in Aqueous Humor of Glaucomatous Eyes and Diabetic Eyes

Purpose: Diabetic retinopathy and glaucoma are the primary causes of acquired blindness. Cytokines including transforming growth factor (TGF)-beta may be involved in these diseases. We therefore collected aqueous humor samples from patients with glaucoma and/or diabetes who were undergoing surgery, and determined the concentration of TGF-beta.

Methods: Aqueous humor samples were collected from 80 patients (84 eyes), including 19 eyes with primary open-angle glaucoma (POAG), 22 eyes with diabetes, and 18 eyes with diabetes complicated with POAG. Twenty-five eyes with cataract served as controls. The concentration of TGF-beta1 or TGF-beta2 was measured by enzyme-linked immunosorbent assay.

Results: The concentration of TGF-beta1 was less than 0.1 pg/mL in all of the groups. In contrast to controls who had 1001.4 +/- 444.1 pg/mL, the concentration of total TGF-beta2 in the diabetes group was 1715.6 +/- 882.1 pg/mL, and that in the diabetes complicated with POAG group was 1692.9 +/- 361.9 pg/mL. These were significantly higher than that in controls. In contrast to the controls who had 321.2 +/- 197.9 pg/mL, the concentration of mature TGF-beta2 with POAG was 822.5 +/- 484.4 pg/mL, and that of diabetes complicated with POAG was 1058.9 +/- 648.4 pg/mL. These were significantly higher than that in the controls. The eyes with diabetes complicated with POAG also had a significantly higher concentration than the eyes with diabetes alone.

Conclusion: Total TGF-beta2 and mature TGF-beta2 in high concentration may correlate with progression of POAG, diabetes, and diabetes complicated with POAG.