Bioscience of microbiota, food and health最新文献

Obesity and type 2 diabetes (T2D) are two of the most common health problems in the world, particularly in adult Asians, with a significant impact on morbidity and mortality. Numerous studies have revealed that the gut microbiome of people with obesity and T2D differs significantly from those of healthy people. Those who suffer from certain illnesses often encounter disruption in their gut microbiome, leading to a decrease in richness diversity and diminished microbial activity. This disruption can also result in the loss of the gut mucosal barrier, increased gut permeability, and most likely, the development of a leaky gut. Recent studies have also emphasized the essential role of the gut microbiome in these conditions. However, conflicting findings were found between one study and another investigation. Therefore, this paper aims to provide an overview of gut microbiome characteristics in adult Asians with obesity, T2D, and the combination of both. In addition, this paper elaborates on the current understanding regarding the association of the gut microbiome with health status, thereby serving as a foundation for developing probiotics or prebiotics to modulate the gut microbiome and improve metabolic health.

Based on liver FibroTouch technology combined with 16S rRNA gene sequencing technology, this study aimed to explore the changes of liver fibrosis indexes and intestinal flora in Wilson's disease (WD) improved by Gandouling (GDL). Ninety patients with WD hepatic fibrosis at the Brain Disease Center of the Anhui Provincial Hospital of Traditional Chinese Medicine were included and randomly divided into an observation group and a control group for a 48-day randomized, double-blind, placebo-controlled trial. Patients in both groups were treated with conventional sodium dimercaptopropanesulfonate, to which GDL was added in the observation group, while the control group was given the corresponding placebo treatment. Before and after treatment, liver stiffness was assessed, blood samples were collected for laboratory tests, and stool samples were collected for 16S rRNA sequencing. Supplementation with GDL significantly improved liver stiffness and non-invasive liver fibrosis modeling indicators, while alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, bile acid, platelets, hyaluronic acid and laminin levels were also significantly improved (p<0.05). Other parameters showed no significant changes. The results of intestinal microbial testing showed that the microbial diversity and composition of the patients in the observation group underwent significant optimization, in which the number of probiotics rose but the number of pathogenic and opportunistic pathogens declined and even basically returned to the normal range. GDL combined with conventional liver-protecting and copper-removing treatments can effectively improve patients' liver fibrosis-related indexes. Furthermore, GDL has the ability to regulate the composition and diversity of the intestinal flora and promote reconstruction of the intestinal microbial community, which in turn may reverse the state of hepatic fibrosis.

Secretory IgA (sIgA) is a class of antibodies that plays a pivotal role in mucosal immunity. The sIgA secreted into the intestinal tract acts to prevent luminal pathogens and food antigens from penetrating across the intestinal epithelial barrier, thereby contributing to the suppression of infections and food allergies. Furthermore, it binds extensively to symbiotic bacteria, exerting a significant impact on the gut microbiota. The antigen recognition specificity of antibodies is determined by the amino acid sequence of the variable region. Therefore, the type of IgA repertoire influences the formation and maintenance of the gut microbiota and susceptibility to infection and food allergy. The initial repertoire of IgA is induced by the extensive colonization of intestinal bacteria during the weaning period and is maintained for an extended period. However, the relationship between the initial gut microbiota and IgA repertoire development has yet to be fully analyzed. In the present study, the weaning gut microbiota was disrupted with antibiotics, and the IgA repertoire was subsequently analyzed in young adulthood. The administration of antibiotics during the weaning period resulted in the suppression of somatic hypermutation in the variable regions of IgA expressed in the small intestine, as well as an impact on multivalent reactivity in IgA during early childhood. Additionally, disturbances in the weaning gut microbiota led to alterations in the microbiota structure of adolescent mice. These findings suggest that the weaning gut microbiota plays a role in promoting the maturation of IgA function.

The study of the relationships between the microbiota and intestinal environment of companion animals has gained increasing attention, particularly concerning health and disease. Previously, we demonstrated that continuous intake of galacto-oligosaccharides (GOS), a prebiotic, can improve the health of household dogs by modulating their gut microbiota. Given the potential health benefits of GOS in cats, we conducted a single-arm open-label study to evaluate the effects of a GOS-containing syrup on the gut microbiota and its metabolites in healthy cats. The study included 25 household cats and was conducted over 12 weeks. Each cat was fed 1.2 g of a GOS-containing syrup per day, equivalent to 0.5 g of GOS. Before the start of the study (week 0), during the 8-week intake period (weeks 4 and 8), and 4 weeks after the intake period (week 12), fecal microbiota, fecal organic acid and putrefactive product concentrations, fecal odor, and serum uremic toxin concentrations were assessed. The results showed that the levels of acetic acid-producing Bifidobacteriaceae significantly increased as a result of GOS intake. Additionally, Peptostreptococcaceae and Eggerthellaceae levels significantly decreased and increased, respectively, due to GOS intake. Furthermore, the concentrations of acetic, propionic, and n-butyric acids in feces significantly increased, whereas serum phenyl sulfate levels decreased significantly. These findings suggested that continuous GOS intake may contribute to the health of household cats.

Older individuals with care needs and lower body mass indices (BMIs) are more likely to be malnourished. Unintentional weight loss, an indicator of malnutrition, significantly impacts the physical function and poor prognosis of older adults. This study aimed to explore the effects of long-term consumption of Lacticaseibacillus paracasei strain Shirota-fermented milk (LcFM) on body weight in the oldest old among nursing-home residents. In total, 118 participants in 21 nursing homes were recruited. Owing to its preliminary nature, randomization and blinding were not conducted, and subjects in the intervention (consuming LcFM daily for 12 months) and non-intervention groups were recruited separately from different nursing homes. Changes in body weight and the proportion of participants with ≥5% body-weight loss were assessed at 6 and 12 months. As intergroup discrepancies in care-needs levels were observed at baseline, a subgroup analysis by these levels was conducted to align baseline characteristics. In the mild care-needs level subgroup (long-term care level ≤2), the LcFM group had a significantly lower proportion of participants with ≥5% weight loss than the control group. Additionally, a subgroup analysis by BMI demonstrated that an effect of LcFM on body weight decline was observed only in the subgroup with a BMI <22 kg/m², which indicates malnutrition risk in older adults. In conclusion, long-term consumption of LcFM might reduce unintentional weight loss in the institutionalized oldest-old individuals who have a risk of malnutrition and have a mild care-needs level. To confirm these preliminary results, further well-designed randomized trials will be required (UMIN000036684).

Non-alcoholic fatty liver disease (NAFLD) is a prevalent liver disorder characterized by hepatic fat accumulation unrelated to alcohol consumption, with its prevalence rising alongside obesity rates. The gut-liver axis reveals that gut microbiota and metabolites significantly impact NAFLD development and progression. This study aimed to investigate the effects of probiotic Lactiplantibacillus plantarum Dad-13 on body weight, liver function, and histopathological features in a rat model of NAFLD. The experimental protocol involved administering probiotic L. plantarum Dad-13 at a dose of 3 × 10⁹ CFU/g over six weeks to rats with NAFLD induced by a high-fat and high-fructose (HFFr) diet. The results demonstrated significant reductions in body and liver weight, improved liver function (serum lipopolysaccharide binding protein, aspartate aminotransferase, and alanine aminotransferase levels), and improved the non-alcoholic liver activity score in rats fed HFFr diets supplemented with probiotics. These findings suggest that supplementation with probiotic L. plantarum Dad-13 is a promising therapeutic intervention for NAFLD.

In a previous study, we found that proteins from cacao beans (cacao proteins) were resistant to digestive enzymes and that ingestion of the indigestible cacao proteins promoted defecation and altered the intestinal microbiota in mice. Therefore, we investigated whether ingestion of dark chocolate containing high amounts of cacao proteins improves constipation and alters the intestinal microbiota in Japanese women. Bowel movement frequency and stool amount after dark chocolate ingestion were significantly higher than before dark chocolate ingestion and significantly higher than after ingestion of white chocolate with no cacao proteins. Next, stool samples were collected, and the intestinal microbiota was analyzed by next-generation sequencing-based 16S rRNA. There was no significant difference in the α-diversity index of the gut microbiota between before and after ingestion of white chocolate, but the α-diversity index of the gut microbiota after ingestion of dark chocolate was significantly higher than before ingestion. The relative abundances of Faecalibacterium and Megamonas in the fecal microbiota after dark chocolate ingestion were significantly higher than before dark chocolate ingestion and significantly higher than after white chocolate ingestion. The relative abundances of Anaerostipes, Butyricicoccus, and Roseburia in the fecal microbiota after dark chocolate ingestion were significantly higher than before ingestion. Spearman correlation analysis revealed a correlation between the stool amount and relative abundances of Megamonas and Roseburia in the dark chocolate ingestion group. These results indicate that ingestion of dark chocolate improved constipation in humans and promoted increase of the relative abundances of butyrate producing bacteria such as Faecalibacterium, Megamonas, Anaerostipes, Butyricicoccus, and Roseburia in the intestinal microbiota.

Due to the requirement for a novel and effective treatment for non-alcoholic fatty liver disease (NAFLD), this study aimed to determine the effects of a novel supplement containing Lactocaseibacillus zeae and Limosilactobacillus reuteri on oxidative stress, inflammation, glucose and lipid metabolism, lipid accumulation, and liver function in the fructose-induced NAFLD rat model. To investigate the involvement of molecular pathways and validate a preclinical study, NAFLD was induced by feeding them fructose-containing drinking water (20% w/v) for 12 consecutive weeks. The fructose-induced male rats were administered a mixture of L. zeae TISTR 2529 and L. reuteri TISTR 2736 at a dose of 2 × 10⁸ CFU/mL during weeks 0 to 12, daily. Weight and food intake were recorded daily. The production of oxidative stress, expression of the TNF-α, SREBP-1c, liver enzymes, and lipid profiles, including the densities of lipid droplets in liver cells, were also evaluated. The results revealed that fructose-induced rats co-treated with the mixed probiotics had significantly decreased body weights, triglycerides, cholesterol, and liver enzymes. Furthermore, the expression of TNF-α, MDA, and SREBP-1c and the densities of lipid droplets in the liver tissue were reduced. Based on the results, the novel probiotic supplement containing L. zeae TISTR 2529 and L. reuteri TISTR 2736 might alleviate NAFLD by normalizing oxidative stress, inflammation, lipid metabolism, and lipid accumulation in the liver of NAFLD-induced model rats.

The gastrointestinal tract is an ecosystem with heterogeneous patterns, distributions, and environments, resulting in different microbial compositions in each gut segment. The relationship between diet and microbiota determines this heterogeneity. Consumption of diets high in fat and carbohydrates (HLHC) is associated with gut dysbiosis, low microbial diversity, and metabolic syndrome (MetS). Functional fiber consumption improves the profile and diversity of the gut microbiota (GM); it stimulates the production of short-chain fatty acids (SCFAs), which act as signaling molecules that maintain the gut barrier integrity and induce hormone synthesis that regulates satiety and glucose metabolism, reducing some MetS parameters. The effect of a dietary intervention with Acanthocereus tetragonus (At), a cactus rich in fiber, antioxidants, amino acids, and minerals traditionally consumed by the Mexican population, is reported here. For this purpose, Wistar rats were randomly divided into three study groups: a control (C) group, a MetS group, and an At-supplemented group. In the MetS and At groups, an HLHC was administered for 12 weeks, inducing MetS. After 18 weeks, stool samples were collected for microbiota sequencing. HLHC administration favored Firmicutes and decreased the abundance of Bacteriodetes at the phylum level in the MetS group. At the genus level, the dietary intervention with At increased the presence of Roseburia, Ruminococcus, Blautia, Bacteroides, and Christensenella, reflecting the effect of A. tetragonus consumption on GM. At diet administration reduced body weight; the plasma glucose, insulin, and lipid levels; and insulin resistance.

In recent years, the gut microbiota has attracted attention due to reported associations with various diseases and health conditions. Gut bacteria have been constantly cultured at 37°C, potentially limiting the understanding of the interaction between them and the host. However, the most dominant human gut microbial species have not been extensively cultured at temperatures other than 37°C. In this study, we analyzed the effects of various culturing temperatures on the growth of the 51 most dominant commensal species as well as 3 harmful bacteria, including Clostridium perfringens, a food poisoning bacterium, in the human intestine. The results showed that the growth of predominant gut microbes varied minimally at body temperatures conducive to human survival but that the growth of several bacteria involved in butyrate production in the intestinal lumen was repressed at temperatures other than 37°C. When cultured at 50°C, the growth of C. perfringens was less inhibited than that of other bacterial species. In addition, the growth of some gut bacteria was unaffected by a body temperature range that was not suitable for human survival.