Cytoprotective Effect of Epigallocatechin Gallate (EGCG)-5'-O-α-Glucopyranoside, a Novel EGCG Derivative.

Epigallocatechin gallate (EGCG) is a well-studied polyphenol with antioxidant effects. Since EGCG has low solubility and stability, many researchers have modified EGCG residues to ameliorate these problems. A novel EGCG derivative, EGCG-5-O--glucopyranoside (EGCG-5Glu), was synthesized, and its characteristics were investigated. EGCG-5Glu showed antioxidant effects in cell and cell-free systems. Under SNP-derived radical exposure, EGCG-5Glu decreased nitric oxide (NO) production, and recovered ROS-mediated cell viability. Moreover, EGCG-5Glu regulated apoptotic pathways (caspases) and cell survival molecules (phosphoinositide 3-kinase (PI3K) and phosphoinositide-dependent kinase 1 (PDK1)). In another radical-induced condition, ultraviolet B (UVB) irradiation, EGCG-5Glu protected cells from UVB and regulated the PI3K/PDK1/AKT pathway. Next, the proliferative effect of EGCG-5Glu was examined. EGCG-5Glu increased cell proliferation by modulating nuclear factor (NF)-B activity. EGCG-5Glu protects and repairs cells from external damage via its antioxidant effects. These results suggest that EGCG-5Glu could be used as a cosmetics ingredient or dietary supplement.