Pear pomace soluble dietary fiber ameliorates the negative effects of high-fat diet in mice by regulating the gut microbiota and associated metabolites

Effects of different fractions of polysaccharides from Dictyophora indusiata on high-fat diet-induced metabolic syndrome in mice

Dictyophora indusiata is a common edible mushroom with great potential in the field of medicine against metabolic disorders, inflammation, and immunodeficiency. Our previous studies have shown that different fractions of the polysaccharide from Dictyophora indusiata (DIP) have various structural characteristics and morphology. However, the impact of the structural features on the protective effects of DIP against metabolic syndrome remains unclear. In this study, three distinct polysaccharide fractions have been extracted from Dictyophora indusiata and a high-fat diet-induced metabolic syndrome (MetS) was constructed in mice. The effects of these fractions on a range of MetS-associated endpoints, including abnormal blood glucose, lipid profiles, body fat content, liver function, intestinal microbiota and their metabolites were investigated. Through correlation analysis, the potential link between the monosaccharide composition of the polysaccharides and their biological activities was determined. The study aimed to explore the potential mechanisms and ameliorative effects of these polysaccharide fractions on MetS, thereby providing statistical evidence for understanding the relationship between monosaccharides composition of Dictyophora indusiata polysaccharides and their potential utility in treating metabolic disorders.

Analysis of the effects of β-mannanase on immune function and intestinal flora in broilers fed the low energy diet based on 16S rRNA sequencing and metagenomic sequencing

As an enzyme, β-mannanase (BM) can be widely used as feed additive to improve the growth performance of animals. This experiment aimed to determine the effect of the addition of BM to low-energy diet on the immune function and intestinal microflora of broiler chickens. In this study, 384 one-day-old Arbor Acres broilers were randomly divided into 3 groups (8 replicates per group): positive control (PC, received a corn-soybean meal basal diet), negative control (NC, received a low-energy diet with Metabolizable Energy (ME) reduced by 50 kcal/kg) and NC + BM group (NC birds + 100 mg/kg BM). All birds were raised for 42 d. The results showed that BM mitigated the damage of immune function in peripheral blood of broilers caused by the decrease of dietary energy level by increasing the Concanavalin A (Con A) index of stimulation (SI) and macrophages phagocytic activity in the peripheral blood of broilers at 42 d (P < 0.05). The analysis of cecum flora showed that the low-energy diet significantly reduced the observed_species index (P < 0.01), Chao1 index and ACE index (P < 0.05), which reduced the abundance and evenness of species in the cecum of broilers at 21 d. It also significantly reduced the relative abundance of Candidatus_Arthromitus and significantly increased the relative abundance of Pseudomonas in the cecum of broilers at 21 d, while also significantly increasing the relative abundance of Monoglobus at 42 d. BM significantly increased the relative abundance of Lachnospiraceae_UCG-001 and Lachnospiraceae_bacterium_615 in the cecum of broilers at 21 d. In addition, BM inhibited microbial Fatty acid degradation by decreasing the activity of glutaryl-CoA dehydrogenase. Collectively, BM could improve intestinal health by enhancing the immune function of broilers, promoting the proliferation of beneficial bacteria and reducing the number of harmful bacteria, regulating intestinal flora, thereby alleviating the adverse effects of lower dietary energy levels.

Synbiotic Combination between Lactobacillus paracasei VL8 and Mannan-Oligosaccharide Repairs the Intestinal Barrier in the Dextran Sulfate Sodium-Induced Colitis Model by Regulating the Intestinal Stem Cell Niche

Previously, Lactobacillus paracasei VL8, a lactobacillus strain isolated from the traditional Finnish fermented dairy product Viili, demonstrated immunomodulatory and antibacterial effects. The prebiotic mannan-oligosaccharide (MOS) further promoted its antibacterial activity and growth performance, holding promise for maintaining intestinal health. However, this has not been verified in vivo. In this study, we elucidated the process by which L. paracasei VL8 and its synbiotc combination (SYN) with MOS repair the intestinal barrier function in dextran sodium sulfate (DSS)-induced colitis mice. SYN surpasses VL8 or MOS alone in restoring goblet cells and improving the tight junction structure. Omics analysis on gut microbiota reveals SYN's ability to restore Lactobacillus spp. abundance and promote tryptophan metabolism. SYN intervention also inhibits the DSS-induced hyperactivation of the Wnt/β-catenin pathway. Tryptophan metabolites from Lactobacillus induce intestinal organoid differentiation. Co-housing experiments confirm microbiota transferability, replicating intestinal barrier repair. In conclusion, our study highlights the potential therapeutic efficacy of the synbiotic combination of Lactobacillus paracasei VL8 and MOS in restoring the damaged intestinal barrier and offers new insights into the complex crosstalk between the gut microbiota and intestinal stem cells.

Modulating the Human Gut Microbiota through Hypocaloric Balanced Diets: An Effective Approach for Managing Obesity

This study aimed to investigate the effects of a hypocaloric balanced diet (HBD) on anthropometric measures and gut microbiota of 43 people with obesity. Fecal samples were collected from the study subjects at weeks 0 and 12, and a detailed analysis of gut microbiota was performed using 16S rRNA gene sequencing. By comparing anthropometric measures and microbiota changes in subjects before and after the HBD intervention, we revealed the potential effects of HBD on weight loss and gut microbiota. Our results indicated that the HBD resulted in a significant decrease in body mass index (BMI), and most of the physiological indicators were decreased to a greater degree in the effective HBD group (EHBD, weight loss ≥ 5%) than in the ineffective HBD group (IHBD, weight loss < 5%). The HBD intervention also modified the gut microbiota of the subjects with obesity. Specifically, Blautia, Lachnoclostridium, Terrisporobacter, Ruminococcus (R. torques, R. gnavus), and Pseudomonas were significantly reduced. In addition, we employed machine learning models, such as XGBRF and GB models, to rank the importance of various features and identified the top 10 key bacterial genera involved. Gut microbiota co-occurrence networks showed the dominance of healthier microbiota following successful weight loss. These results suggested that the HBD intervention enhanced weight loss, which may be related to diet-induced changes in the gut microbiota.

Antioxidant Capacity and Protective Effects on H2O2-Induced Oxidative Damage in PC12 Cells of the Active Fraction of Brassica rapa L

Brassica rapa L. (BR), a traditional biennial herb belonging to the Brassica species of Brassicaceae, has been widely used for functions of anti-inflammatory, antitumor, antioxidation, antiaging, and regulation of immunity. In this study, antioxidant activity and protective effects on H2O2-induced oxidative damage in PC12 cells of the active fractions of BR were investigated in vitro. Among all active fractions, the ethyl acetate fraction of ethanol extract from BR (BREE-Ea) showed the strongest antioxidant activity. Additionally, it was noted that BREE-Ea and n-butyl alcohol fraction of ethanol extract from BR (BREE-Ba) both have protective effects in oxidatively damaged PC12 cells, while BREE-Ea displayed the best protective effect in all determined experimental doses. Furthermore, flow cytometry (DCFH-DA staining) analysis indicated that BREE-Ea could reduce the H2O2-induced apoptosis in PC12 cells by reducing the production of intracellular reactive oxygen species (ROS) and increasing enzymatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Moreover, BREE-Ea could decrease the malondialdehyde (MDA) content and reduce the release of extracellular lactic dehydrogenase (LDH) from H2O2-induced PC12 cells. All these results demonstrate that BREE-Ea has a good antioxidant capacity and protective effect on PC12 cells against apoptosis induced by H2O2 and that it can be used as a good edible antioxidant to improve the body's endogenous antioxidant defense.

Salidroside protects mice from high-fat diet-induced obesity by modulating the gut microbiota

Obesity is a systemic disease with multisystem inflammation associated with gut dysbiosis. Salidroside (SAL) which is a major glycoside extracted from Rhodiola rosea L. has a wide range of pharmacological effects, but the role of gut microbiota in the protective effects of SAL on obesity has not been studied. Herein, we aim to explore whether SAL could ameliorate high-fat diet (HFD)-induced obesity in mice by modulating microbiota. Results showed that oral treatment with SAL alleviated HFD-induced obesity in mice as evidenced by body weight and fat weight. SAL supplementation effectively attenuated fat accumulation, lipid synthesis genes expression, liver inflammation, and metabolic endotoxemia. In addition, SAL treatment alleviated intestinal damage and increased the expression of mucin protein (Mucin-2) and tight junction (TJ) proteins (Occludin and Zonula Occludens-1). 16S rRNA sequencing analysis revealed that the gut microbiota of obese mice was also partly improved by SAL via restoring the microbial community structure and diversity. A fecal microbiota transplantation (FMT) study was designed to verify the causality. Compared with fecal transplantation (FM) from the HFD-treated mice, FM from the SAL-treated mice significantly mitigate the symptoms of obese mice, including decreasing body weight, fat accumulation, and attenuating pathological damage in the gut. Thus, SAL could be a remarkable candidate to prevent obesity.