Research progress of natural plant polysaccharides inhibiting inflammatory signaling pathways and regulating intestinal flora and metabolism to protect inflammatory bowel disease

Investigating the Alleviating Effect of Fucoidan from Apostichopus japonicus on Ulcerative Colitis by Mice Experiments and In Vitro Simulation of Human Fecal Fermentation

BACKGROUND

Fucoidan from Apostichopus japonicus (Aj-FUC) is a marine polysaccharide extracted from the high-quality sea cucumber, which has received increasing attention for its multiple biological activities.

METHODS

In this study, Aj-FUC was extracted, and its basic structure was characterized, while the alleviating efficacy of Aj-FUC on ulcerative colitis (UC) was investigated using C57BL/6 mice. The improvement of Aj-FUC on the fecal gut microbiota in healthy individuals and inflammatory bowel disease (IBD) patients was explored using in vitro simulated fecal fermentation.

RESULTS

The results reflected that Aj-FUC treatment attenuated the histopathological damage associated with colitis, reduced the levels of IL-6, IL-1β, and TNF-α. Aj-FUC treatment also upregulated the expression of ZO-1 and occludin, thereby aiding in the repair of the intestinal barrier. Furthermore, Aj-FUC enhanced the levels of short-chain fatty acids (SCFAs) and helped restore the balance of gut microbiota, particularly by increasing the relative abundance of Akkermansia. In vitro simulation of fecal fermentation showed that Aj-FUC could modulate the gut microbiota of IBD patients and increase the relative abundance of beneficial bacteria.

CONCLUSIONS

In conclusion, this study highlights that Aj-FUC can alleviate UC by modulating the levels of inflammatory factors, improving the intestinal barrier, and regulating the intestinal flora in a variety of ways.

Colon-Targeted Ginseng Polysaccharides-Based Microspheres for Improving Ulcerative Colitis via Anti-Inflammation and Gut Microbiota Modulation

Natural plant-derived polysaccharides exhibit substantial potential for treating ulcerative colitis (UC) owing to their anti-inflammatory and antioxidant properties and favorable safety profiles. However, their practical application faces several challenges, including structural instability in gastric acid, imprecise targeting of inflamed regions, and limited intestinal retention times. To address these limitations, pH-responsive, colon-targeting microspheres (pWGPAC MSs) are developed for delivering phosphorylated wild ginseng polysaccharides (pWGP) to alleviate UC. These pWGPAC MSs are fabricated by incorporating pWGP into calcium-crosslinked alginate microspheres with subsequent chitosan surface modification to enhance mucosal adhesion. These pWGPAC MSs demonstrated exceptional stability under acidic conditions while enabling targeted release in the colon. In a mouse model of UC, the pWGPAC MSs effectively mitigated mucosal injury, attenuated inflammation, and restored intestinal barrier function. Further mechanistic investigations revealed that these pWGPAC MSs modulated the TLR4/MYD88 signaling pathway and promoted M2 macrophage polarization. Integrated microbiome and metabolome analyses demonstrated that these pWGPAC MSs regulated the gut microbiota composition and decreased pro-inflammatory metabolite levels. In addition, these microspheres demonstrated promising safety profiles. Collectively, these findings establish pWGPAC MSs as a promising therapeutic strategy for the treatment of UC and provide a solid foundation for future clinical applications.

The neurotoxicity of acrylamide in ultra-processed foods: interventions of polysaccharides through the microbiota-gut-brain axis

Ultra-processed foods (UPFs) have become popular in recent years, however, the detrimental effects of their excessive consumption have also become evident. Acrylamide (AA), a processing hazard present in UPFs, can further aggravate the harmful effects of UPFs. AA can cause significant damage to both the intestinal barrier and gut microbiota, thereby affecting the nervous system through the microbiota-gut-brain (MGB) axis. Natural polysaccharides have demonstrated the capacity to significantly alleviate the oxidative stress and inflammatory response associated with AA exposure. In addition, they exhibit neuroprotective properties that may be mediated through the MGB axis. This paper reviews literature on the presence of AA in certain UPFs and its potential to inflict serious harm on the human gut microbiota and brain. Moreover, the possibility of utilizing polysaccharides as a preventative measure against AA-induced neurotoxicity was also proposed. These findings provide new insights into the safety risks associated with the overconsumption of UPFs and highlight the potential of polysaccharides to counteract the neurodegeneration induced by AA.

Dietary Pleurotus citrinopileatus Polysaccharide Improves Growth Performance and Meat Quality Associated with Alterations of Gut Microbiota in Arbor Acre Broilers

Adding edible fungal polysaccharides to animal diets improves growth performance, meat quality, intestinal health, and immunity without adverse effects. This study aimed to evaluate the impact of Pleurotus citrinopileatus polysaccharide (PCP, including PCP250, PCP500, PCP750, and PCP1000 mg/kg) on the growth performance, meat quality, and microbial composition of Arbor Acre (AA) broilers (total 180) by metabolomics and high-throughput sequencing. The results showed that adding PCP enhanced chicken meat tenderness, redness (a*), and water retention and raised essential amino acids and flavor amino acids (such as umami and sweet amino acids) content. The metabolomics revealed that IMP, creatine, betaine, sarcosine, and taurine were related to improving meat quality in broilers by PCP addition. In addition, amino acid, purine, and lipid metabolism were the main metabolic pathways. Moreover, PCP could regulate muscle metabolism by increasing the relative abundance of Lachnospiraceae and Lactobacillus and the content of short-chain fatty acids (SCFAs). Therefore, PCP may become a promising new dietary supplement in the future, which may improve the yield and quality of broiler chickens.

Enhancing immunomodulation in cyclophosphamide-induced immunosuppressed mice through targeted modulation of butyrate-producing gut microbiota via oral administration of astragalus polysaccharides

Astragalus polysaccharide is one of the most extensively studied traditional Chinese medicinal polysaccharides because of its immunomodulatory activity and has attracted considerable attention. Existing evidence suggests that its potential immunomodulatory mechanism is related to the modulation of intestinal microbiota. However, current research methods on the gut microbiota mainly focus on 16S rRNA sequencing, providing limited evidence of specific changes in functional bacterial groups in the intestine. Butyrate is a class of short-chain fatty acids among the microbial metabolites in the gut and is most closely associated with immunomodulatory activity. Thus, in this study, we extracted and purified a polysaccharide from astragalus composed of a main chain of →4)-α-D-Glcp-(1 → and →4,6)-α-D-Glcp-(1→, with side chains of →6)-α-D-Glcp-(1→ and aggregated arabinose, and investigated the changes in butyrate-producing bacterial groups in mice during the immunomodulation process of astragalus polysaccharide, using two butyrate-producing bacterial-specific primers. The results showed that oral administration of astragalus polysaccharide significantly increased butyrate production in the mouse intestine, restoring the disrupted butyrate-producing bacterial abundance and diversity caused by immunosuppression. In conclusion, our study provides the first evidence of the targeted modulation of the butyrate-producing gut microbiota by astragalus polysaccharide, offering insights into its pharmacological activity.

Bioactive Polysaccharides from Gracilaria lemaneiformis: Preparation, Structures, and Therapeutic Insights

Gracilaria lamaneiformis, a red seaweed, is an abundant source of bioactive polysaccharides with significant health-promoting properties. Nevertheless, the broad application of G. lamaneiformis in the nutraceutical and pharmaceutical sectors remains constrained due to the absence of comprehensive data. This review provides a detailed examination of the preparation methods, structural characteristics, and biological activities of G. lamaneiformis polysaccharides (GLPs). We explore both conventional and advanced extraction techniques, highlighting the efficiency and yield improvements achieved through methods such as microwave-, ultrasonic-, and enzyme-assisted extraction. The structural elucidation of GLPs using modern analytical techniques, including high-performance liquid chromatography, gas chromatography, and nuclear magnetic resonance spectroscopy, is discussed, providing comprehensive insights into their molecular composition and configuration. Furthermore, we critically evaluate the diverse biological activities of GLPs, including their antioxidant, anti-inflammatory, antitumor, and gut microbiota modulation properties. This review underscores the therapeutic potential of GLPs and suggests future research directions to fully harness their health benefits.

Houttuynia cordata thunb. alleviates inflammatory bowel disease by modulating intestinal microenvironment: a research review

Inflammatory bowel disease (IBD) is a complex group of chronic intestinal diseases, the cause of which has not yet been clarified, but it is widely believed that the disorder of the intestinal microenvironment and its related functional changes are key factors in the development of the disease. Houttuynia cordata thunb. is a traditional plant with abundant resources and long history of utilization in China, which has attracted widespread attention in recent years due to its potential in the treatment of IBD. However, its development and utilization are limited owing to the aristolochic acid alkaloids contained in it. Therefore, based on the relationship between the intestinal microenvironment and IBD, this article summarizes the potential mechanisms by which the main active ingredients of Houttuynia cordata thunb., such as volatile oils, polysaccharides, and flavonoids, and related traditional Chinese medicine preparations, such as Xiezhuo Jiedu Formula, alleviate IBD by regulating the intestinal microenvironment. At the same time, combined with current reports, the medicinal and edible safety of Houttuynia cordata thunb. is explained for providing ideas for further research and development of Houttuynia chordate thunb. in IBD disease, more treatment options for IBD patients, and more insights into the therapeutic potential of plants with homology of medicine and food in intestinal diseases, and even more diseases.