title: A polysaccharide isolated from Cordyceps sinensis, a traditional Chinese medicine, protects PC12 cells against hydrogen peroxide-induced injury.
abstract: Cordyceps sinensis, a well-known traditional Chinese medicine, possesses activities in anti-tumour, anti-oxidation and stimulating the immune system; however, the identity of active component(s) is not determined. By using anti-oxidation activity-guided fractionation, a polysaccharide of molecular weight approximately 210 kDa was isolated from cultured Cordyceps mycelia by ion-exchange and sizing chromatography. The isolated polysaccharide, having strong anti-oxidation activity, contains glucose, mannose and galactose in a ratio of 1 : 0.6 : 0.75. The pre-treatment of isolated polysaccharide on the cultured rat pheochromocytoma PC12 cells shows strong protective effect against hydrogen peroxide (H(2)O(2))-induced insult. Treatment of the cells with the isolated polysaccharide at 100 microg/ml prior to H(2)O(2) exposure significantly elevated the survival of PC12 cells in culture by over 60%. In parallel, the H(2)O(2)-induced production of malondialdehyde in cultured cells was markedly reduced by the polysaccharide treatment. Moreover, the pre-treatment of the isolated polysaccharide significantly attenuated the changes of glutathione peroxidase and superoxide dismutase activities in H(2)O(2)-treated cells in a dose-dependent manner. This is the first report in identifying a polysaccharide from Cordyceps, which protects against the free radical-induced neuronal cell toxicity.
authors.affiliation: Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau, China.
authors.forename: Shao P
authors.initials: SP
authors.lastname: Li
authors.forename: Kui J
authors.initials: KJ
authors.lastname: Zhao
authors.forename: Zhao N
authors.initials: ZN
authors.lastname: Ji
authors.forename: Zong H
authors.initials: ZH
authors.lastname: Song
authors.forename: Tina T X
authors.initials: TT
authors.lastname: Dong
authors.forename: Chun K
authors.initials: CK
authors.lastname: Lo
authors.forename: Jerry K H
authors.initials: JK
authors.lastname: Cheung
authors.forename: Shang Q
authors.initials: SQ
authors.lastname: Zhu
authors.forename: Karl W K
authors.initials: KW
authors.lastname: Tsim
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D032661:Cordyceps / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D005979:Glutathione Peroxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity*; D008315:Malondialdehyde / Q000378:metabolism; D008516:Medicine, Chinese Traditional; D016716:PC12 Cells; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D020011:Protective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D011134:Polysaccharides; D020011:Protective Agents; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase