Proteomic analysis of aqueous humor from patients with primary open angle glaucoma

[摘要] Purpose: Primary open angle glaucoma(POAG) is a leading cause of irreversible blindness on a global level.Researchers have yet to specify the exact mechanisms of POAG; therespective relationships between POAG and elevated intraocular pressure(IOP), as well as optic neuropathy, remain particularly unclear. It isknown, however, that the expression profile for some proteins in theaqueous humor (AH) changes in some diseases, and that AH changes playimportant roles in elevated IOP. To identify the possible roles ofthese AH proteins in POAG, a proteomic analysis of the AH compositionsof POAG patients’ eyes was performed and compared with those derivedfrom paired, non-POAG cataract (control) eyes. Methods: We used Bradford’s method todetermine total protein concentration in AH, and analyzed separationprofiles via two-dimensional (2D) gel electrophoresis. We used silverstain to determine gel proteins, and analyzed separation profiles toassess spot density differences between POAG and non-POAG patients.These gel spots were isolated and identified via mass spectrometry.Prostaglandin H2 D-isomerase (PGDS) in AH were analyzed by westernBlotting. Results: There was no significantdifference between the total protein concentration in AH of POAGpatients and that in AH of non-POAG patients. A total of seven spotswere increased in 2D gels from POAG patients. The spots were derivedfrom PGDS, caspase 14 precursor, transthyretin, cystain C, albuminprecursor, and tranferrin. And PGDS in AH from patients was more thanfrom controls. Conclusions: The protein composition inAH was significantly different in POAG patients versus non-POAGpatients. The identified proteins could be a potential biomarker forPOAG and may play a role in the mechanisms of elevated IOP and opticneuropathy in POAG.

[学科分类] 生物化学/生物物理