title: A homogalacturonan from the radix of Platycodon grandiflorum and the anti-angiogenesis activity of poly-/oligogalacturonic acids derived therefrom.
abstract: A polysaccharide, PGA4-3b, with an average molecular weight of 8.9kDa estimated by high-performance gel-permeation chromatography (HPGPC), was isolated from radix of Platycodon grandiflorum (Jacq.) A. DC. Using monosaccharide analysis, methylation analysis and NMR spectroscopy, PGA4-3b was elucidated to be a linear poly-(1→4)-α-d-galactopyranosyluronic acid that contains no methyl ester groups. Partial acid hydrolysis of PGA4-3b yielded a series of poly- or oligogalacturonic acids with different degrees of polymerization (DP), that is, 4-3bde, 4-3bde-O-1, 4-3bde-O-2, 4-3bde-O-3, and 4-3bde-O-4. Cell tube formation inhibition tests with human microvascular endothelial cells (HMEC) for antiangiogenesis analysis showed that 4-3bde-O-1 and 4-3bde-O-2, the fractions with higher molecular weights, could inhibit tube formation, while the native PGA4-3b and low molecular weight fraction 4-3bde-O-3 and 4-3bde-O4 are ineffective. Moreover, 4-3bde-O-2 with DP 5-10 impaired cell tube formation in a dose-dependent way, suggesting its potential to be developed as an anti-angiogenesis drug. This is the first time oligogalacturonic acids are reported to show an anti-angiogenesis effect.
authors.affiliation: Shanghai Institutes of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Yuxia
authors.initials: Y
authors.lastname: Xu
authors.forename: Qun
authors.initials: Q
authors.lastname: Dong
authors.forename: Hong
authors.initials: H
authors.lastname: Qiu
authors.forename: Chung-Wah
authors.initials: CW
authors.lastname: Ma
authors.forename: Kan
authors.initials: K
authors.lastname: Ding
mesh_terms: D020533:Angiogenesis Inhibitors / Q000737:chemistry* / Q000494:pharmacology*; D002460:Cell Line; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D018919:Neovascularization, Physiologic / Q000187:drug effects; D009844:Oligosaccharides / Q000737:chemistry* / Q000494:pharmacology*; D010368:Pectins / Q000737:chemistry* / Q000494:pharmacology*; D031238:Platycodon / Q000737:chemistry*
chemical_list: D020533:Angiogenesis Inhibitors; D009844:Oligosaccharides; C412763:oligogalacturonic acid; D010368:Pectins; C003181:polygalacturonic acid