Minor phenolics from Angelica keiskei and their proliferative effects on Hep3B cells

A new coumarin, (-)-cis-(3'R,4'R)-4'-O-angeloylkhellactone-3'-O-β-d-glucopyranoside (1) and two new chalcones, 3'-[(2E)-5-carboxy-3-methyl-2-pentenyl]-4,2',4'-trihydroxychalcone (4) and (±)-4,2',4'-trihydroxy-3'-{2-hydroxy-2-[tetrahydro-2-methyl-5-(1-methylethenyl)-2-furanyl]ethyl}chalcone (5) were isolated from the aerial parts of Angelica keiskei (Umbelliferae), together with six known compounds: (R)-O-isobutyroyllomatin (2), 3'-O-methylvaginol (3), (-)-jejuchalcone F (6), isoliquiritigenin (7), davidigenin (8), and (±)-liquiritigenin (9). The structures of the new compounds were determined by interpretation of their spectroscopic data including 1D and 2D NMR data. All known compounds (2, 3, and 6-9) were isolated as constituents of A. keiskei for the first time. To identify novel hepatocyte proliferation inducer for liver regeneration, 1-9 were evaluated for their cell proliferative effects using a Hep3B human hepatoma cell line. All isolates exhibited cell proliferative effects compared to untreated control (DMSO). Cytoprotective effects against oxidative stress induced by glucose oxidase were also examined on Hep3B cells and mouse fibroblast NIH3T3 cells and all compounds showed significant dose-dependent protection against oxidative stress.