Sulfated heteropolysaccharides from Undaria pinnatifida: Structural characterization and transcript-metabolite profiling of immunostimulatory effects on RAW264.7 cells

Lihong Yang; Jun Liu; Xuewei Xia; Io Nam Wong; Sookja Kim Chung; Baojun Xu; Hesham R El-Seedi; Bin Wang; Riming Huang

doi:10.1016/j.fochx.2022.100251

Sulfated heteropolysaccharides from Undaria pinnatifida: Structural characterization and transcript-metabolite profiling of immunostimulatory effects on RAW264.7 cells

Food Chem X. 2022 Feb 9:13:100251. doi: 10.1016/j.fochx.2022.100251. eCollection 2022 Mar 30.

Authors

Lihong Yang^{1

2}, Jun Liu³, Xuewei Xia², Io Nam Wong⁴, Sookja Kim Chung⁴, Baojun Xu⁵, Hesham R El-Seedi⁶, Bin Wang¹, Riming Huang²

Affiliations

¹ Shenzhen Hospital of Integrated Traditional Chinese and Western Medicine, Shenzhen 518104, China.
² Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou 510642, China.
³ Laboratory of Pathogenic Biology, Guangdong Medical University, Zhanjiang 524023, China.
⁴ Faculty of Medicine, Macau University of Science and Technology, Macau, China.
⁵ Food Science and Technology Program, BNU-HKBU United International College, Zhuhai 519087, China.
⁶ Pharmacognosy Group, Department of Pharmaceutical Biosciences, Biomedical Centre, Uppsala University, Uppsala, Box 591, SE 751 24, Sweden.

Abstract

Investigation of the polysaccharides from an edible marine brown algae Undaria pinnatifida has led to obtaining three fractional sulfated polysaccharides UPPs 1-3 with molecular weights of 7.212 kDa, 13.924 kDa, and 55.875 kDa, respectively. All UPPs are composed of galactose, xylose, glucose, mannose, glucuronic acid, and mannuronic acid, while UPP-3 also consisted of fucose, arabinose, and fructose. The immunostimulatory assay revealed that UPP-3 had important effects on cell viability, nitric oxide levels, and secretion of cytokines TNF-α and IL-6 in RAW264.7 cells. Furthermore, the transcript-metabolite data along with western blot and immunofluorescent staining revealed that UPP-3 could stimulate the Toll-like receptor (TLR4) associated with the nuclear factor kappa-B (NF-κB) p65 signaling pathway of RAW264.7 cells. These findings of the immunomodulatory sulfated polysaccharide will provide a basic understanding to further exploitation of U. pinnatifida polysaccharides.

Keywords: Immunostimulatory; Metabolome; Polysaccharide; Structural characterization; Transcriptome; Undaria pinnatifida.