Gender-related differences in the effects of Inonotus obliquus polysaccharide on intestinal microorganisms in SD rats model

Effects of sex on fat deposition through gut microbiota and short-chain fatty acids in weaned pigs

Nitrogen pollution resulting from excessive feed consumption poses a significant challenge for modern swine production. Precision nutrition technology seems to be an effective way to solve this problem; therefore, understanding the law of pig body composition deposition is a prerequisite. This study investigated the sex effects on growth performance, body composition, nutrient deposition, gut microbiota, and short-chain fatty acids (SCFA) in weaned piglets. Eighty weaned pigs were randomly allocated to 2 treatments according to the sex of pigs. An individual pig was considered as a treatment replicate. Six body weights (BW 5, 7, 11, 15, 20, and 25 kg) were chosen as experimental points; for each point 10 piglets close to the average BW (5 males and 5 females) were slaughtered, and there was one growth phase between each 2 BW points. Results indicated that the males had higher average daily gain (ADG) and average daily feed intake (ADFI) compared to the females (P < 0.05) at growth phases 15 to 20 kg BW and 20 to 25 kg BW. Meanwhile, males at 20 kg BW had higher body fat content than females (P < 0.10). Males showed a higher body fat (P < 0.05) deposition rate at phase 15 to 20 kg BW (P < 0.05) than females. For pigs at 20 kg BW, the relative abundance of RuminococcaceaeUCG-005, Clostridium, Christensenellaceae_R-7_group, and Peptostreptococcaceae was significantly increased in males (P < 0.05) but that of Bifidobacterium was decreased (P < 0.05). At 25 kg BW, the relative abundance of Ruminococcaceae_NK4A214_group, Fibrobacter, RuminococcaceaeUCG-009, Ralstonia, Klebsiel, and Christensenellaceae_R-7_group in males was higher when compared with females (P < 0.05). In terms of SCFA, females exhibited higher concentrations of propionate compared to males (P < 0.05). The results of the current study indicated that sex influenced fat deposition through changes in the composition of gut microbiota and the content of SCFA, which has significant implications for the realization of precision nutrition in modern swine production.

In Vitro Characterization of Polysaccharides from Fresh Tea Leaves in Simulated Gastrointestinal Digestion and Gut Microbiome Fermentation

Tea plants have a long cultivation history in the world, but there are few studies on polysaccharides from fresh tea leaves. In this study, tea polysaccharides (TPSs) were isolated from fresh tea leaves. Then, we investigated the characteristics of TPSs during in vitro simulated digestion and fermentation; moreover, the effects of TPSs on gut microbiota were explored. The results revealed that saliva did not significantly affect TPSs' molecular weight, monosaccharide composition, and reducing sugar content, indicating that TPSs cannot be digested in the oral cavity. However, TPSs were partially decomposed in the gastrointestinal tract after gastric and intestinal digestion, resulting in the release of a small amount of free glucose monosaccharides. Our in vitro fermentation experiments demonstrated that TPSs are degraded by gut microbiota, leading to short-chain fatty acid (SCFA) production and pH reduction. Moreover, TPSs increased the abundance of Bacteroides, Lactobacillus, and Bifidobacterium but reduced that of Escherichia, Shigella, and Enterococcus, demonstrating that TPSs can regulate the gut microbiome. In conclusion, TPSs are partially decomposed by gut microbiota, resulting in the production of SCFAs and the regulation of gut microbiota composition and function. Therefore, TPSs may be used to develop a prebiotic supplement to regulate the gut microbiome and improve host health.

Polysaccharides from Dendrobium officinale improve obesity-induced insulin resistance through the gut microbiota and the SOCS3-mediated insulin receptor substrate-1 signaling pathway

BACKGROUND

Obesity induces insulin resistance and chronic inflammation, impacting human health. The relationship between obesity, gut microbiota, and regulatory mechanisms has been studied extensively. Dendrobium officinale polysaccharide (DOP), a traditional Chinese herbal medicine, potentially reduces insulin resistance. However, the mechanism through which DOP affects gut microbiota and alleviates obesity-induced insulin resistance in rats requires further investigation.

RESULTS

The current study aimed to assess the impact of DOP on gut microbiota and insulin resistance in rats on a high-fat diet. The results revealed that DOP effectively reduced blood lipids, glucose disorders, oxidative stress, and inflammatory infiltration in the liver of obese Sprague Dawley rats. This was achieved by downregulating SOCS3 expression and upregulating insulin receptor substrate-1 (IRS-1) by regulating the JAK/STAT/SOCS3 signaling pathway. Notably, DOP intervention enhanced the abundance of beneficial gut microbiota and reduced harmful microbiota. Correlation analysis demonstrated significant associations among intestinal microbiota, SOCS3-mediated IRS-1 expression, and inflammatory factors.

CONCLUSION

Dendrobium officinale polysaccharide regulated the gut microbiota, enhanced IRS-1 expression, and mitigated liver injury and insulin resistance due to a high-fat diet. These findings depict the potential anti-insulin resistance properties of DOP and offer further evidence for addressing obesity and its complications. © 2023 Society of Chemical Industry.

Structural analysis of polysaccharide from Inonotus obliquus and investigate combined impact on the sex hormones, intestinal microbiota and metabolism in SPF male mice

The dysregulation of sex hormone levels is associated with metabolic disorders such as obesity. Inonotus obliquus polysaccharide (IOP) exhibits a promising therapeutic effect on conditions like obesity and diabetes, potentially linked to its influence on intestinal microbiota and metabolism. The exact cause and mechanisms that link sex hormones, gut microbiota and metabolism are still unknown. In this research, we examined the molecular weight, monosaccharide composition, and glycosidic bond type of IOP. We found that IOP mostly consists of alpha-structured 6‑carbon glucopyranose, with a predominant (1 → 4) linkage to monosaccharides and a uniform distribution. Following this, we administered two different concentrations of IOP to mice through gavage. The results of the enzyme-linked immunosorbent assay (ELISA) demonstrated a significant increase in testosterone (T) levels in the IOP group as compared to the control group. Additionally, the results of tissue immunofluorescence indicated that increased IOP led to a decrease in adiponectin content and an increase in SET protein expression. The study also revealed changes in the intestinal microbiota and metabolic changes in mice through 16S rRNA data and non-targeted LC-MS data, respectively. The study also found that IOP mainly affects pathways linked to glycerophospholipid metabolism. In addition, it has been observed that there is an increase in the number of beneficial bacteria, such as the Eubacterium coprostanoligenes group and g.Lachnospiraceae NK4A136 group, while the levels of metabolites that are linked to obesity or diabetes, such as 1,5-anhydrosorbitol, are reduced. Furthermore, biomarker screening has revealed that the main microorganism responsible for the differences between the three groups is g.Erysipelatoclostridiaceae. In summary, these findings suggest that IOP exerts its therapeutic effects through a synergistic interplay between sex hormones, gut microbiome composition, and metabolic processes.

Inonotus obliquus polysaccharide are linear molecules that alter the abundance and composition of intestinal microbiota in Sprague Dawley rats

Introduction

The macromolecular polysaccharide Inonotus obliquus polysaccharide (IOP) is composed of various monosaccharides, and it could modulate the composition and diversity of intestinal flora. However, its impact on the intestinal flora in rats of different genders remains unclear. Therefore, this study aims to investigate the structural changes of IOP and its effects on the intestinal flora after administration in male and female rats.

Methods

In this study, the molecular weight and purity of IOP were analyzed by high-performance gel permeation chromatography (HPGPC) and phenol sulfuric acid method, and NMR was used to confirm the chemical structure of IOP. Sex hormone [testosterone (T) and estradiol (E2)] levels and intestinal microbial changes were detected by enzyme-linked immunosorbent assay (ELISA) and 16S rRNA, respectively, after gavage of IOP (100 mg/kg) in male and female Sprague Dawley (SD) rats.

Results

HPGPC analysis showed that the average molecular weight (Mw) of IOP was 4,828  Da, and the total sugar content of the purified IOP was 96.2%, indicating that the polysaccharide is of high purity. NMR revealed that IOP is a linear macromolecule with an α-D-type glucose backbone. The results of ELISA and 16S rRNA showed that the IOP increased the abundance of beneficial bacteria, such as Clostridia_UCG-014 and Prevotellaceae_NK3B31, and reduced that of harmful bacteria, such as Colidextribacter and Desulfobacterota in the intestine of both male and female rats, and IOP changed the levels of sex hormones in male and female rats. Further analyses revealed that the increase in alpha diversity was higher in male than female rats. α diversity and β diversity revealed a significant difference in the composition of cecal microbiota between male and female rats in the control group, but IOP intake reduced this difference. Meanwhile, α analysis revealed a change in the composition of bacterial flora was more stable in male than female rats.

Conclusions

This study enhances our comprehension of the IOP structure and elucidates the alterations in intestinal flora following IOP administration in rats of varying genders. Nonetheless, further investigation is warranted to explore the specific underlying reasons for these discrepancies.