Aqueous Humor Endothelin-1 (Et-1), Vascular Endothelial Growth Factor (VEGF) and Cyclooxygenase-2 (COX-2) levels in Mexican Glaucomatous Patients

Abstract

Purpose: To evaluate the concentration of endothelin-1, vascular endothelial growth factor, and cyclooxygenase-2 in aqueous humor from normal and glaucomatous human patients.

Material and Methods: Concentrations of these proteins were measured using ELISA kits in 83 patients (30 presenting for cataract surgery and 53 with glaucoma).

Results: Endothelin-1, vascular endothelial growth factor, and cyclooxygenase-2 were detected in all samples. The ages of the patients with glaucoma (64.51 ± 17.51 years) and cataracts subjects (59.30 ± 19.15 years) were similar. The endothelin-1 concentration in cataracts patients (48.55 ± 9.50 pg/ml) was statistically different when compared to endothelin-1 concentration in aqueous humor from primary open-angle glaucoma (107.94 ± 12.20 pg/ml) and neovascular glaucoma (114.68 ± 25.50 pg/ml) (p < 0.05). No statistical difference was observed in normal tension glaucoma group (69.14 ± 52.80 pg/ml) (p > 0.05). Vascular endothelial growth factor concentration was higher in neovascular glaucoma (81.84 ± 6.40 pg/ml), being the difference statistically significant when compared with the other groups (p < 0.0001). Cyclooxygenase-2 levels showed no statistical difference between cataract groups and any other glaucoma group (p > 0.05). No effect of age, gender, or previously medication of aqueous humor concentration of these proteins could be detected (p > 0.05).

Conclusion: In this study we observed increased levels of endothelin-1 in aqueous humor from patients with primary open-angle glaucoma and neovascular glaucoma, and increased levels of vascular endothelial growth factor only in neovascular glaucoma patients, raising a possible connection between endothelin-1 and vascular endothelial growth factor in the role of some types of glaucoma. Regarding cyclooxygenase-2 levels detected, perhaps indicate that low values of cyclooxygenase-2 are necessary for normal functions of the eye.

KEYWORDS::

• Aqueous humor
• Endothelin-1
• VEGF
• COX-2
• Glaucoma

ACKNOWLEDGMENTS

The authors wish to thank all doctors from the Glaucoma Department, Asociación Para Evitar la Ceguera en México, Hospital Dr. Luis Sánchez Bulnes, IAP, and a special thanks to Dr. Rafael Castañeda Diez for personally helping to get the aqueous humor samples. Also, the authors wish to thank Ms. Vaslly Ayala Ceja for all of her support and patience.

Declaration of interest: The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.