Effects of Lycium Barbarum Polysaccharides on the Metabolism of Dendritic Cells: An In Vitro Study

Abstract

Targeting dendritic cells (DCs) metabolism-related pathways and in-situ activation of DCs have become a new trend in DC-based immunotherapy. Studies have shown that Lycium barbarum polysaccharide can promote DCs function. This study is aimed at exploring the mechanism of LBP affecting DCs function from the perspective of metabolomics. MTT method was used to detect the activity of DC2.4 cells. ELISA kit method was used to detect the contents of IL-6, IL-12, and TNF-α in the supernatant of cells. Ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was used to detect general changes in DC2.4 cell metabolism. And then multidistance covariates and bioinformatics, partial least squares-discriminant analysis (PLS-DA) were used to analyze differential metabolites. Finally, metabolic pathway analysis was performed by MetaboAnalyst v5.0. The results showed that LBP had no significant inhibitory effect on the activity of DC2.4 cells at the experimental dose of 50-200 μg/ml. LBP (100 μg/ml) could significantly stimulate DC2.4 cells to secrete IL-6, TNF-α, and IL-12. Moreover, 20 differential metabolites could be identified, including betaine, hypoxanthine, L-carnitine, 5’-methylthioadenosine, orotic acid, sphingomyelin, and L-glutamine. These metabolites were involved 28 metabolic pathways and the top 5 metabolic pathways were aspartate metabolism, pyrimidine metabolism, phenylacetate metabolism, methionine metabolism, and fatty acid metabolism. These results suggest that the effect of LBP on DCs function is related to the regulation of cell metabolism.

Dietary Plant Polysaccharides for Cancer Prevention: Role of Immune Cells and Gut Microbiota, Challenges and Perspectives

“…Research demonstrates that polysaccharides from Portulaca oleracea L. are effective in the prevention of tumor growth by inducing the maturation of DCs and increasing the protein expression levels of CD80 in tumor cells [67]. Other research results also demonstrate that polysaccharides from Lycium barbarum possess the ability to stimulate the maturation of DCs, which facilitates the enhancement of the immune response and anti-tumor activity [21,68].…”

A comprehensive review on the ethnobotany, phytochemistry, pharmacology and quality control of the genusLyciumin China

“…116,117 Additionally, LBP was proven to induce the phenotypic and functional maturation of dendritic cells (DCs) through the regulation of cell metabolism. 118…”

Natural polysaccharides exert anti-tumor effects as dendritic cell immune enhancers

“…Zhang et al. ( 105 ) used UPLC-Q-TOF/MS to detect changes in the metabolism of DCs in the LBP group versus the control group and identified four significantly different metabolites, with betaine, hypoxanthine, and DL threonine-beta-methylaspartic acid increased in the LBP group and L-glutamine significantly decreased in the LBP group. Of these metabolites, hypoxanthine has been shown to cause DCs to exhibit mature morphological features, including increased cell volume and nuclear volume, more open chromatin, and more prominent protrusions ( 106 ).…”