Pharmacokinetics and Metabolites of 12 Bioactive Polymethoxyflavones in Rat Plasma
Qiang You, Dan Li, Haiyan Ding, Hongping Chen, Yuan Hu, Youping Liu
Abstract
Polymethoxyflavones (PMFs) are a subgroup of flavonoids possessing various health benefits. 3,5,7,4′-Tetramethoxyflavone (1), 5,6,7,4′-tetramethylflavone (2), 3,7,3′,4′-tetramethoxyflavone (3), 5,7,3′,4′-tetramethoxyflavone (4), 5-hydroxy-3,7,2′,4′-tetramethoxyflavone (5), 3,5,7,2′,4′-pentamethoxyflavone (6), 5-hydroxy-3,7,3′,4′-tetramethoxyflavone (7), 3-hydroxy-5,7,3′,4′-tetramethylflavone (8), 3,5,7,3′,4′-pentamethoxyflavone (9), 5-hydroxy-3,7,3′,4′,5′-pentamethoxyflavone (10), 3-hydroxy-5,7,3′,4′,5′-pentamethoxyflavone (11), and 3,5,7,3′,4′,5′-hexamethoxylflavone (12) were 12 bioactive and available PMFs. The aim of this study was to investigate the pharmacokinetic, metabolite, and antitumor activities as well as the structure–pharmacokinetic–antitumor activity relationships of these 12 PMFs to facilitate further studies of their medicinal potentials. The cytotoxicity of PMFs with a hydroxy group toward HeLa, A549, HepG2, and HCT116 cancer cell lines was generally significantly more potent than that of PMFs without a hydroxy group. Compounds 5, 7, 8, 10, and 11 were all undetectable in rat plasma, while compounds 1–4, 6, 9, and 12 were detectable. Both the number and position of hydroxy and methoxy groups played an important role in modulating PMF pharmacokinetics and metabolites.