title: A protein-bound polysaccharide from the stem bark of Eucommia ulmoides and its anti-complementary effect.
abstract: Bioactivity-guided fractionation of a hot-water extract from the stem bark of Eucommia ulmoides led to the isolation of a homogeneous polysaccharide EWDS-2, which was identified as a highly branched protein-bound polysaccharide with average molecular weight between 1000 and 2000kDa, composed of Glc, Gal, Ara, and Rha in the ratio of 2.2:1.0:0.4:0.2, along with traces of Man and 6.55% of protein. The main linkages of the residues of EWDS-2 include terminal, 1,3-linked, 1,4-linked, 1,2,6-linked, 1,3,6-linked Glc; 1,6-linked, 1,2,6-linked, 1,3,4-linked, 1,4,6-linked Gal; 1,5-linked, 1,3,5-linked Ara; terminal and 1,2,5-linked Rha. The bioassay revealed that EWDS-2 inhibits complement activation on both the classic and alternative pathways with CH(50) and AP(50) values of 282+/-11mug/mL and 144+/-17mug/mL, respectively. Preliminary mechanism studies indicate that EWDS-2 inhibits the activation of the complement system by interacting with C1q, C1r, C1s, C2, C3, C4, C5, and C9. The results suggested that EWDS-2 could be valuable for the treatment of diseases associated with the excessive activation of the complement system.
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 200032, People's Republic of China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Zhu
authors.forename: Hongye
authors.initials: H
authors.lastname: Di
authors.forename: Yunyi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jianwen
authors.initials: J
authors.lastname: Zhang
authors.forename: Daofeng
authors.initials: D
authors.lastname: Chen
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects; D003167:Complement Activation / Q000187:drug effects*; D031283:Eucommiaceae / Q000737:chemistry*; D006168:Guinea Pigs; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008297:Male; D024301:Plant Bark / Q000737:chemistry*; D010940:Plant Proteins / Q000378:metabolism*; D018547:Plant Stems / Q000737:chemistry*; D011134:Polysaccharides / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D010940:Plant Proteins; D011134:Polysaccharides