Ginseng Polysaccharides and its Effective Subfraction Protects Against Dextran Sodium Sulfate-Induced Colitis via Regulating NF-κB Signaling Pathway, Recovering Intestinal Barrier and Adjusting Gut Microbiota

Background: Polysaccharides from Panax ginseng is a natural carbohydrates with multiple activities. Our previous work found that ginseng polysaccharide could recover the gut microbiota dysbiosis caused by antibiotic. However, it was little known about its functions on colitis. In this study, we aim to investigate the protective effects of ginseng polysaccharide (WGP), its neutral fraction (WGPN) and acidic fraction (WGPA) on dextran sodium sulfate (DSS) induced colitis and the potential mechanisms with pharmacological experiments.Methods: Animal model of DSS-induced colitis was constructed by male Wistar rats. Disease activity index (DAI) scores, weight increment, colon weights, and colon length were recorded. Physiological and histological parameters, tight junctions proteins, inflammatory factors, gut microbiota, short-chain fatty acids (SCFAs) and NF-kB signalling pathway related proteins were compared among the five experimental groups, which were treated with a normal diet (Con group), DSS (DSS group), WGP (WGP group), WGPN (WGPN group), and WGPA (WGPA group), respectively. Results: Both WGP and WGPA alleviated the colitis symptoms and colon structure changes of colitis rats. They can decreased the DAIs and improved colon health; reduced colon damage and recovered intestinal barrier via regulating the tight-junction related proteins (ZO-1 and Occludin); downregulated inflammatory cytokines (IL-1β, IL-2, IL-6, and IL-17) and inhibited the TLR4/MyD88/NF-kB signalling pathway in the colon; regulated the diversity and composition of gut microbiota, especially the relative abundance of Ruminococcus; enhanced the production of SCFAs. Conclusions: WGP exerted had a protective effect against colitis through regulating NF-kB signaling pathway, recovering intestinal barrier and adjusting gut microbiota, with its acidic fraction (WGPA) primarily contributing to this activity. The results support to the utilization and investigation of ginseng polysaccharides as potential intervention strategy for the prevention of colitis.

Insight Into Polysaccharides From Panax ginseng C. A. Meyer in Improving Intestinal Inflammation: Modulating Intestinal Microbiota and Autophagy

Polysaccharides from Panax ginseng C. A. Meyer (P. ginseng) are the main active component of P. ginseng and exhibit significant intestinal anti-inflammatory activity. However, the therapeutic mechanism of the ginseng polysaccharide is unclear, and this hinders the application for medicine or functional food. In this study, a polysaccharide was isolated from P. ginseng (GP). The primary structure and morphology of the GP were studied by HPLC, FT-IR spectroscopy, and scanning electron microscopy (SEM). Further, its intestinal anti-inflammatory activity and its mechanism of function were evaluated in experimental systems using DSS-induced rats, fecal microbiota transplantation (FMT), and LPS-stimulated HT-29 cells. Results showed that GP modulated the structure of gut microbiota and restored mTOR-dependent autophagic dysfunction. Consequently, active autophagy suppressed inflammation through the inhibition of NF-κB, oxidative stress, and the release of cytokines. Therefore, our research provides a rationale for future investigations into the relationship between microbiota and autophagy and revealed the therapeutic potential of GP for inflammatory bowel disease.

The Synergistic Effects of Polysaccharides and Ginsenosides From American Ginseng (Panax quinquefolius L.) Ameliorating Cyclophosphamide-Induced Intestinal Immune Disorders and Gut Barrier Dysfunctions Based on Microbiome-Metabolomics Analysis

Cyclophosphamide (CTX), used in cancer chemotherapy, a high dose of which would cause immunosuppressive effect and intestinal mucosa damage. American ginseng (Panax quinquefolius L.) has a long history of functional food use for immunological disorder, colitis, cancer, and so on. This study aimed to illustrate the underlying mechanism of American ginseng’s immunomodulatory effect in CTX-induced mice. In this study, all groups of American ginseng (American ginseng polysaccharide [AGP], American ginseng ginsenoside [AGG], co-treated with American ginseng polysaccharide and ginsenoside [AGP_AGG]) have relieve the immune disorder by reversing the lymphocyte subsets ratio in spleen and peripheral blood, as well as stimulating CD4+T cells and IgA-secreting cells in small intestine. These three treatment groups, especially AGP_AGG co-treated group recovered the intestine morphology that up-regulated villus height (VH)/crypt depth (CD) ratio, areas of mucins expression, quantity of goblet cells, and expression of tight junction proteins (ZO-1, occludin). Importantly, the microbiome-metabolomics analysis was applied in this study to illustrate the possible immuno-modulating mechanism. The synergistic effect of polysaccharides and ginsenosides (AGP_AGG group) restored the gut microbiota composition and increased various beneficial mucosa-associated bacterial taxa Clostridiales, Bifidobacterium, and Lachnospiraceae, while decreased harmful bacteria Escherichia-Shigella and Peptococcaceae. Also, AGP_AGG group altered various fecal metabolites such as uric acid, xanthurenic acid, acylcarnitine, 9,10-DHOME, 13-HDoHE, LysoPE15:0, LysoPC 16:0, LysoPI 18:0, and so on, that associated with immunometabolism or protective effect of gut barrier. These results suggest AG, particularly co-treated of polysaccharide and ginsenoside may be used as immunostimulants targeting microbiome-metabolomics axis to prevent CTX-induced side effects in cancer patients.

Structural characterization of ginseng oligopeptides and anti-aging potency evaluation in Caenorhabditis elegans

The functions of ginseng polysaccharide have been widely explored, yet, the antiaging activity of ginseng oligopeptides (GOPs) has not been well explored.