A connection between levels of soluble Fas and Fas ligand in the aqueous humor and the parameters of structural and functional damage of glaucoma patients

Abstract

Introduction/Objective Fas ligand (FasL) induces apoptosis when interacting with the Fas-receptor. The aim was to determine the concentration of soluble Fas (sFas) and soluble FasL (sFasL) in the aqueous humor (AH) of open-angle glaucoma patients, and establish a connection between these markers of apoptosis and the parameters of structural and functional glaucoma damage. Methods This study examined 88 AH samples; 35 primary open-angle glaucoma with elevated intraocular pressure (POAG-HTG) patients, 24 open angle pseudoexfoliative glaucoma patients (XFG) and 29 patients with senile cataract (CAT). The concentration of sFas and sFasL was determined by commercial ELISA tests in the AH. Results The conducted study showed that AH sFas concentration was the highest in XFG (720.14 ± 167.39 pg/ml), and slightly lower in POAG-HTG (713.43 ± 162.69 pg/ml), than in cataract patients (632.46 ± 217.11 pg/ml), without statistical significance. There was a significant negative correlation of sFas concentration and thickness of the peripapillary nerve fibers of the retina (RNFL) inferior thickness in POAG-HTG (p < 0.05). The concentration of sFasL was the lowest in POAG-HTG (9.28 ± 0.551 pg/ml), higher in XFG (9.45 ± 0.61 pg/ml; p = 0.0566), and the highest in the cataract group (9.48 ± 0.73 pg/ml). A negative correlation of sFasL and MD in the POAG-HTG, and a negative correlation with RNFL superior in the XFG were significant. Conclusion sFasL has an active role in the regulation of the inflammatory process in glaucoma. sFas and sFasL, as markers of apoptosis, are associated with the parameters of structural, RNFL thinning, and functional glaucoma damage, namely visual field defects.

Keywords

• fas
• fasl
• aqueous humor
• open angle glaucoma
• hypertensive glaucoma
• pseudoexfoliation