1. Structural Characterization and Anti-complementary Activities of Two Polysaccharides from Houttuynia cordata.
- Author
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Lu, Yan, Zhang, Juan-Juan, Huo, Jiang-Yan, and Chen, Dao-Feng
- Subjects
GLUCOSE analysis ,BLOOD coagulation ,CELLULOSE ,CHROMATOGRAPHIC analysis ,COMPLEMENT (Immunology) ,ELECTRON microscopy ,GAS chromatography ,IMMUNOLOGIC diseases ,INFRARED spectroscopy ,MAGNETIC resonance imaging ,MASS spectrometry ,MONOSACCHARIDES ,PLANT extracts ,POLYSACCHARIDES ,ACYCLIC acids ,HEXOSES ,THERAPEUTICS - Abstract
In previous studies, crude Houttuynia cordata polysaccharides showed beneficial effects on acute lung injury in vivo , a syndrome in which anti-complementary activities played an important role. Anti-complementary activity-guided fractionation of H. cordata polysaccharides led to the isolation of two highly branched homogeneous polysaccharides, HC-PS1 and HC-PS3, with a molecular weight of 274 530 and 216 384 Da, respectively. The polysaccharides were purified by chromatography on DEAE-cellulose and Superdex columns. Their structural characterization was performed by IR, GC-MS, methylation, NMR, and SEM analysis. Both HC-PS1 and HC-PS3 are composed of eight types of monosaccharides, including rhamnose, arabinose, mannose, glucose, glucuronic acid, galactose, galacturonic acid, and xylose. The main linkages of the sugar residues in HC-PS1 include terminal Rha p , terminal and 1,5-linked Ara f ; 1,3,6-linked and 1,4,6-linked Man p ; terminal, 1,4-linked, 1,3-linked, 1,3,6-linked and 1,4,6-linked and 1,3,4,6-linked Glc p ; and terminal, 1,4-linked and 1,6-linked Gal p. The main monosaccharide linkages in HC-PS3 are similar to that of HC-PS1, except the additional 1,3,4-linked Man p and the absence of 1,3,6-linked Glc p. HC-PS1 and HC-PS3 were found to inhibit complement activation through both the classical and alternative pathways with 50% inhibition concentrations of 0.272 – 0.318 mg/mL without interfering with the coagulation system. Preliminary mechanism studies indicated that both HC-PS1 and HC-PS3 inhibited the activation of the complement system by interacting with C2, C4, and C5. The results suggest that HC-PS1 and HC-PS3 could be valuable for the treatment of diseases associated with the excessive activation of the complement system. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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