Chapter 57 - Molecular Pathways, Green Tea Extract, (−)-Epigallocatechin Gallate, and Ocular Tissue

Abstract

Green tea extract and (−)-epigallocatechin gallate (EGCG), extracted from the plant Carmellia sinensis, have long been known as effective antioxidants. EGCG has multifunctional properties, including anti-inflammatory, anti-ischemic, antineovascularization, antineurodegenerative, and other effects. This chapter describes the protective effects of green tea extract and EGCG on ocular tissues, including corneal epithelium cells, human lens epithelial cells, and retinal pigment epithelium cells. Green tea extract and EGCG affect a variety of molecular events, from receptor-mediated processes to signaling and altered gene expression. Green tea extract and EGCG could play important roles in the treatment of many ophthalmologic diseases, such as dry eye disease, keratitis, corneal ischemia, corneal trauma or degeneration, cataract, age-related macular degeneration, ocular hypertension, glaucoma, ocular infections, and other eye-related pathology. Most of the studies reviewed in this chapter are in vitro or animal experiments, so further human investigations are necessary.