The Role of Epigallocatechin-3-Gallate (EGCG) in Inhibiting Post-Trabeculectomy Fibrosis through the Inhibition of TGF-ß and VEGF

This literature review focuses on the role of epigallocatechin-3-gallate (EGCG), a potent antioxidant found in green tea, in inhibiting post-trabeculectomy fibrosis, particularly through the inhibition of transforming growth factor-beta (TGF-ß) and vascular endothelial growth factor (VEGF). The primary goal of glaucoma treatment is to reduce intraocular pressure (IOP) and prevent optic nerve damage, with trabeculectomy being a common surgical procedure to achieve this. However, the success of this surgery can be compromised by excessive subconjunctival scarring, leading to a failure rate of about 15% within the first few months. EGCG has demonstrated antifibrotic properties, making it a promising therapeutic option for preventing fibrosis after trabeculectomy. The review highlights that Tenon fibroblasts, which are crucial in wound healing and scar formation, can be influenced by EGCG to reduce the risk of fibrosis. The mechanism involves the suppression of myofibroblast differentiation and the modulation of pro-inflammatory cytokines through pathways such as NF-κB and PI3k/Akt. The review also discusses the comparative effectiveness of EGCG against traditional antifibrotic agents like mitomycin C (MMC), which, while effective, can lead to side effects such as ocular toxicity and infection. Furthermore, the review emphasizes the importance of understanding the fibrogenic activity of human Tenon's capsule fibroblasts (HTFs) derived from glaucoma patients, which exhibit a higher propensity for fibrosis compared to those from non-glaucoma patients. This increased fibrogenic activity is linked to elevated expression of pro-fibrotic genes and a higher myofibroblast-to-fibroblast ratio. In conclusion, the findings suggest that EGCG could serve as a valuable adjunct therapy in preventing post-trabeculectomy fibrosis, potentially improving surgical outcomes for glaucoma patients. Further research is warranted to explore the optimal concentrations and mechanisms of action of EGCG in this context.