Scope Sulfated polysaccharide from sea cucumber (SCSP), Stichopus japonicus, has been shown to prevent diverse diseases, but little is known about its effects on obesity and gut microbiota in mice fed a high‐fat diet (HFD). Methods and results Diet‐induced obese, BALB/c mice are fed an HFD with or without SCSP and depolymerized SCSP (d‐SCSP, 0.004 kcal g−1) for 8 weeks. The results show that both SCSP and d‐SCSP reduce body weight, fat and liver hypertrophy, insulin resistance, and serum lipid and inflammatory cytokine levels in HFD‐fed mice. Moreover, SCSP and d‐SCSP not only prevent HFD‐induced gut disorder, as indicated by the enriched probiotic Akkermansia and reduce endotoxin‐bearing Proteobacteria, but also improve the SCFAs and endotoxin (LPS) levels and gut tissue index. Spearman's correlation analysis reveals that several specific genera are strongly correlated with obesity‐related indexes. In addition, the inhibitory effect of d‐SCSP on fat accumulation is more effective than that of SCSP, which may be related to their different regulation of the gut microbiota. Conclusions These findings suggest that SCSP can prevent diet‐induced obesity and its associated diseases by modulating the gut microbiota and improving microbial metabolites and gut tissue, and its effects can be enhanced by free‐radical depolymerization.

Increasing evidence suggests that gut microbiota underpin the development of health and longevity. However, our understanding of what influences the composition of this community of the longevous has not been adequately described. Therefore, illumina sequencing analysis was performed on the gut microbiota of centenarians (aged 100-108 years; RC) and younger elderlies (aged 85-99 years; RE) living in Bama County, Guangxi, China and the elderlies (aged 80-92 years; CE) living in Nanning City, Guangxi, China. In addition, their diet was monitored using a semiquantitative dietary questionary (FFQ 23). The results revealed the abundance of Roseburia and Escherichia was significantly greater, whereas that of Lactobacillus, Faecalibacterium, Parabacteroides, Butyricimonas, Coprococcus, Megamonas, Mitsuokella, Sutterella, and Akkermansia was significantly less in centenarians at the genus level. Both clustering analysis and UniFraq distance analysis showed structural segregation with age and diet among the three populations. Using partial least square discriminate analysis and redundancy analysis, we identified 33 and 34 operational taxonomic units (OTUs) as key OTUs that were significantly associated with age and diet, respectively. Age-related OTUs were characterized as Ruminococcaceae, Clostridiaceae, and Lachnospiraceae, and the former two were increased in the centenarians; diet-related OTUs were classified as Bacteroidales, Lachnospiraceae, and Ruminococcaceae. The former two were deceased, whereas the later one was increased, in the high-fiber diet. The age and high-fiber diet were concomitant with changes in the gut microbiota of centenarians, suggesting that age and high-fiber diet can establish a new structurally balanced architecture of gut microbiota that may benefit the health of centenarians.

Increasing attention focuses on the relationship between neuroinflammation and Alzheimer’s disease (AD). The reports on the microbiota–gut–brain axis reveal that the regulation by gut microbiota is an effective way to intervene in neuroinflammation-related AD. In this study, two novel selenium peptides (Se-Ps), VPRKL­(Se)­M (Se-P1) and RYNA­(Se)­MNDYT (Se-P2), with neuroprotection effects were obtained from Se-enriched Cordyceps militaris. Se-P1 and Se-P2 pre-protection led to a 30 and 33% increase in the PC-12 cell viability compared to the damage group, respectively. Moreover, Se-Ps exhibited a significant pre-protection against LPS-induced inflammatory and oxidative stress in the colon and brain by inhibiting the production of pro-inflammatory mediators (p < 0.05) and malondialdehyde, as well as promoting anti-inflammatory cytokine level and antioxidant enzyme activity (p < 0.05), which may alleviate the cognitive impairment in LPS-injured mice (p < 0.05). Se-Ps not only repaired the intestinal mucosa damage of LPS-injured mice but also had a positive effect on gut microbiota dysbacteriosis by increasing the abundance of Lactobacillus and Alistipes and decreasing the abundance of Akkermansia and Bacteroides. Collectively, the antioxidant, anti-inflammatory, and regulating properties on gut microflora of Se-Ps contribute to their neuroprotection, supporting that Se-Ps could be a promising dietary supplement in the prevention and/or treatment of AD.

No abstract