BACKGROUND: Glaucoma, a neurodegenerative disease often linked to elevated intraocular pressure (IOP) and trabecular meshwork (TM) dysfunction, involves oxidative stress and fibrosis. This in vitro study evaluated the impact of various Plasma Rich in Growth Factors (PRGF-Endoret(R)) eye drops formulations, differing in platelet and plasma concentrations, on oxidative stress and fibrotic responses in primary human trabecular meshwork cells (TMCs). METHODS: TMCs were exposed to hydrogen peroxide (H(2)O(2)) to induce oxidative stress and transforming growth factor beta-2 (TGF-beta2) to stimulate fibrotic conditions. Protective and reversal effects of PRGF formulations (1-2, 1-4, 1-6, 2-4 L, and 2-6 L) were assessed by measuring reactive oxygen species (ROS), cell viability, extracellular matrix (ECM) components (glycosaminoglycans, hyaluronan), and fibrotic markers (alpha-smooth muscle actin, collagen I, fibronectin) at both protein and gene expression levels. RESULTS: All PRGF formulations significantly protected against and reversed H(2)O(2)-induced oxidative stress. Similarly, PRGF treatments effectively counteracted TGF-beta2-induced fibrotic differentiation by reducing ECM deposition and the expression of alpha-SMA, collagen I, and fibronectin. The standard PRGF formulation (1-2) demonstrated comparable efficacy to formulations with higher platelet or plasma concentrations. CONCLUSIONS: These in vitro results indicate that PRGF eye drops possess notable antioxidant and antifibrotic properties in TMCs, suggesting its potential as a therapeutic intervention to preserve trabecular meshwork function and potentially lower intraocular pressure in glaucoma. The established 1-2 PRGF formulation appears to be a robust option for mitigating key cellular processes implicated in glaucoma pathogenesis. Further in vivo studies and IOP models are essential to validate these findings and elucidate the underlying therapeutic mechanisms.