Preparation, characterization and immunomodulatory effects of unsaturated sulfated oligoguluronic acid

Decheng Bi; Jinfeng Huang; Jue Cao; Lijun Yao; Wushuang Guo; Zhenqing Zhang; Yan Wu; Hong Xu; Zhangli Hu; Xu Xu

doi:10.1016/j.carbpol.2022.120370

Preparation, characterization and immunomodulatory effects of unsaturated sulfated oligoguluronic acid

Carbohydr Polym. 2023 Feb 1;301(Pt B):120370. doi: 10.1016/j.carbpol.2022.120370. Epub 2022 Nov 21.

Authors

Decheng Bi¹, Jinfeng Huang², Jue Cao², Lijun Yao², Wushuang Guo³, Zhenqing Zhang⁴, Yan Wu⁵, Hong Xu², Zhangli Hu², Xu Xu⁶

Affiliations

¹ Shenzhen Key Laboratory of Marine Bioresources and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, PR China; College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, PR China.
² Shenzhen Key Laboratory of Marine Bioresources and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, PR China.
³ Department of Stomatology, Shenzhen University General Hospital, Shenzhen University, Shenzhen 518055, PR China; Institute of Stomatological Research, Shenzhen University, Shenzhen 518055, PR China.
⁴ College of Pharmaceutical Sciences, Soochow University, Suzhou 215006, PR China.
⁵ Instrumental Analysis Center, Shenzhen University, Shenzhen 518060, PR China.
⁶ Shenzhen Key Laboratory of Marine Bioresources and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, PR China. Electronic address: xuxu@szu.edu.cn.

PMID: 36446502
DOI: 10.1016/j.carbpol.2022.120370

Abstract

Polyguluronic acid (PG) is a type of polysaccharide found in edible brown seaweeds. This study synthesized a new sulfated saccharide (SOGA) by sulfating PG-derived unsaturated oligoguluronic acid (OGA). The molecular weight and degree of sulfate-group substitution of SOGA were 1.6 kDa and 1.03, respectively. The structures of PG, OGA, and SOGA were elucidated using FT-IR and NMR spectroscopy. Furthermore, the immunomodulatory effects of PG, OGA, and SOGA on LPS-triggered RAW264.7 and BV2 cells were evaluated. SOGA, but not PG or OGA, significantly reduced the LPS-stimulated overproduction of proinflammatory mediators and suppressed the activation of corresponding signalling pathways. Also, SOGA could actively regulate immune balance by inhibiting apoptosis and pyroapoptosis. These results suggested that SOGA is a potential therapeutic agent for the prevention of diseases associated with immune disorders owing to its remarkable immunomodulatory effects, and that sulfate groups in the carbohydrate chain play a crucial role for its bioactivities.

Keywords: Apoptosis; Immunomodulatory effects; Pyroptosis; Signalling pathway; Structural characterization; Unsaturated sulfated oligoguluronic acid.

MeSH terms

Immunomodulation
Lipopolysaccharides* / pharmacology
Spectroscopy, Fourier Transform Infrared
Sulfates*
Sulfur Oxides

Substances

Sulfates
Lipopolysaccharides
Sulfur Oxides