Bioscience of microbiota, food and health最新文献

Depression is a prevalent mental health disorder, and its incidence has increased further because of the coronavirus disease 2019 (COVID-19) pandemic. The gut microbiome has been suggested as a potential target for mental health treatment because of the bidirectional communication system between the brain and gastrointestinal tract, known as the gut-brain axis. We aimed to investigate the relationship between the human gut microbiome and depression screening by analyzing the abundance and types of microbiomes among individuals living in Japan, where mental health awareness and support may differ from those in other countries owing to cultural factors. We used a data-driven approach to evaluate the gut microbiome of participants who underwent commercial gut microbiota testing services and completed a questionnaire survey that included a test for scoring depressive tendencies. Our data analysis results indicated that no significant differences in gut microbiome composition were found among the groups based on their depression screening scores. However, the results also indicated the potential existence of a few differentially abundant bacterial taxa. Specifically, the detected bacterial changes in abundance suggest that the Bifidobacteriaceae, Streptococcaceae, and Veillonellaceae families are candidates for differentially abundant bacteria. Our findings should contribute to the growing body of research on the relationship between gut microbiome and mental health, highlighting the potential of microbiome-based interventions for depression treatment. The limitations of this study include the lack of clear medical information on the participants' diagnoses. Future research could benefit from a larger sample size and more detailed clinical information.

Probiotics such as bifidobacteria have been given to low-birth-weight neonates (LBWNs) at risk for a disrupted gut microbiota leading to the development of serious diseases such necrotizing enterocolitis. Recently prebiotics such as lactulose are used together with bifidobacteria as synbiotics. However, faster and more powerful bifidobacteria growth is desired for better LBWN outcomes. The prebiotic 1-kestose has a higher selective growth-promoting effect on bifidobacteria and lactic acid bacteria in vitro among several oligosaccharides. Twenty-six premature neonates (less than 2,000 g) admitted to a neonatal intensive care unit (NICU) were randomly assigned to receive Bifidobacterium breve M16-V with either 1-kestose or lactulose once a day for four weeks from birth. A 16S rRNA gene analysis revealed similar increases in alpha-diversity from 7 to 28 days in both groups. The most dominant genus on both days was Bifidobacterium in both groups, with no significant difference between the two groups. Quantitative PCR analysis revealed that the number of Staphylococcus aureus tended to be lower in the 1-kestose group than in the lactulose group at 28 days. The number of Escherichia coli was higher in the 1-kestose group at 7 days. The copy number of total bacteria in the 1-kestose group was significantly higher than that in the lactulose group at 3 time points, 7, 14, and 28 days. No severe adverse events occurred in either group during the study period. l-Ketose may offer an alternative option to lactulose as a prebiotic to promote the development of gut microbiota in LBWNs.

The gut microbiota plays a crucial role in both the pathogenesis and alleviation of host depression by modulating the brain-gut axis. We have developed a murine model of human depression called the subchronic and mild social defeat stress (sCSDS) model, which impacts not only behavior but also the host gut microbiota and gut metabolites, including bile acids. In this study, we utilized liquid chromatography/mass spectrometry (LC/MS) to explore the effects of sCSDS on the mouse fecal bile acid profile. sCSDS mice exhibited significantly elevated levels of deoxycholic acid (DCA) and lithocholic acid (LCA) in fecal extracts, leading to a notable increase in total bile acids and 7α-dehydroxylated secondary bile acids. Consequently, a noteworthy negative correlation was identified between the abundances of DCA and LCA and the social interaction score, an indicator of susceptibility in stressed mice. Furthermore, analysis of the colonic microbiome unveiled a negative correlation between the abundance of CDCA and Turicibacter. Additionally, DCA and LCA exhibited positive correlations with Oscillospiraceae and Lachnospiraceae but negative correlations with the Eubacterium coprostanoligenes group. These findings suggest that sCSDS impacts the bidirectional interaction between the gut microbiota and bile acids and is associated with reduced social interaction, a behavioral indicator of susceptibility in stressed mice.

Diversion colitis (DC) is characterized by mucosal inflammation in the defunctioned segment of the colon following a colostomy or ileostomy. The major causes of DC are an increase in the number of aerobic bacteria, a lack of short-chain fatty acids (SCFAs), and immune disorders in the diverted colon. However, its exact pathogenesis remains unknown. Various treatment strategies for DC have been explored, although none have been definitively established. Treatment approaches such as SCFAs, 5-aminosalicylic acid enemas, steroid enemas, and irrigation with fibers have been attempted, yielding various degrees of efficacies in mitigating mucosal inflammation. However, only individual case reports demonstrating the limited effect of the following therapies have been published: leukocytapheresis, dextrose (hypertonic glucose) spray, infliximab, an elemental diet, and coconut oil. The usefulness of probiotics for treating DC has recently been reported. Furthermore, fecal microbiota transplantation (FMT) has emerged as a promising treatment for DC. This review provides an update on the treatment strategies of DC, with a particular focus on FMT and its relationship with the intestinal microbiota. FMT may become the first choice of treatment for some patients in the future because of its low medical costs, ease of use, and minimal side effects. Furthermore, FMT can also be used for postoperative DC prophylaxis.

Lactic acid bacteria (LAB) are a type of bacteria that convert carbohydrates into lactate through fermentation metabolism. While LAB mainly acquire energy through this anaerobic process, they also have oxygen-consuming systems, one of which is flavoprotein oxidase and the other is exogenous heme- or heme- and quinone-dependent respiratory metabolism. Over the past two decades, research has contributed to the understanding of the roles of these oxidase machineries, confirming their suspected roles and uncovering novel functions. This review presents the roles of these oxidase machineries, which are anticipated to be critical for the future applications of LAB in industry and comprehending the virulence of pathogenic streptococci.

This research aimed to examine the effect of daily intake of food containing Lactococcus lactis strain T21 (T21) on skin conditions and inflammation-related markers in healthy adults who experience itching because of dry skin and have an atopic predisposition. A randomized, double-blind, placebo-controlled parallel-group study was conducted on 44 subjects aged 20 to 64 years. Subjects were randomly assigned to receive a T21-containing food or placebo daily for 8 weeks. The hydration of stratum corneum, trans-epidermal water loss, skin brightness (L*), skin redness (a*), and quality of life (QOL) scores were evaluated. Moreover, SCCA2, Th1/Th2, peripheral blood eosinophil count, TGF-β1, TARC, total IgE, and LDH were measured as inflammation-related markers. The results showed that, compared with the placebo, food containing T21 reduced trans-epidermal water loss in the neck and increased neck skin brightness (L*) after 8 weeks of consumption. Furthermore, a stratified analysis in subjects with a history of atopy showed improvements in neck skin redness (a*) and skin-related QOL. No significant improvement in inflammation-related markers was observed. Intake of food containing T21 for 8 weeks in healthy adult with atopic predisposition was suggested to improve skin barrier function in the neck and brightness in the neck skin. Furthermore, the results also suggested that it had the effect of improving rough skin and reducing discomfort due to dryness in healthy adults with a history of atopy.

Nukadoko, a fermented rice bran bed for pickling vegetables called nukazuke, has a complex microbiota. Within it, deep interactions between the microbiota of the pickled vegetables and nukadoko characterize and control the qualities of both products. To address this notion, we monitored the changes in the microbiota of nukadoko and nukazuke while pickling different vegetables. Raw or roasted rice bran was mixed with salted water and fermented at 24°C for 40 days, following which different species of vegetable, Cucumis sativus var. sativus, Brassica oleracea var. capitata, or Raphanus sativus var. hortensis, were pickled. The microbial composition of the washing solution of fresh vegetables, as well as that of the nukadoko and nukazuke for each vegetable, was analyzed by amplicon sequencing of 16S rRNA genes. Although the microbiota of nukadoko varied depending on the species of pickled vegetables, no transcolonization of any species of bacteria from fresh vegetables to nukadoko was observed. However, some lactic acid bacterium (LAB) species eventually dominated the microbiota of both nukazuke and matured nukadoko, although they were not detected in either the fresh vegetables or rice bran. Particularly, Lactiplantibacillus plantarum was dominant among all pairs of pickled vegetables and matured nukadoko, whereas the transcolonization of some other LAB species was observed in a pickled vegetable-specific manner. Staphylococcus xylosus was observed to some extent in each nukadoko, yet it was not detected in any nukazuke. Overall, a LAB-dominant microbiota was established in both nukadoko and nukazuke in an underlying process that was different but partly common among vegetables.

The present study aimed to investigate the peculiarities of adaptation of tissue elements of the gastric mucosa during interaction with Helicobacter pylori, as determined by genetic characteristics of the bacterium and the host. Venous blood and biopsy samples of the mucosa of the antrum and body of the stomach from young patients (18 to 25 years old) were examined. The condition of the gastric mucosa was assessed using stained histological preparations. Venous blood was collected from the patients to ascertain the polymorphisms of the IL-lß and IL-IRN genes. The most pronounced changes were observed in the parameters of reparative regeneration of epithelial differentiation during colonization of the gastric mucosa by H. pylori strains carrying the CagA(+) and BabA2(+) genes. These included an increase in proliferation and apoptosis rates and alterations in epithelial differentiation markers characterized by elevated production of Shh and MUC5AC, as well as a reduction in the production of the protective mucin MUC6 by isthmus gland cells. The presence of the vacAs1 and vacAs2 genes of H. pylori results in a high level of apoptosis in epithelial cells without accelerating proliferation. It was found that after eradication, patients with preserved cellular infiltrates in their gastric mucosa plates were carriers of mainly the IL-1ß*T/IL-1RN*2R haplotypes after 12 months.

Interest is growing in the relationship of the microbiota and intestinal environment with health in companion animals. Galacto-oligosaccharides (GOS), typical prebiotics, are expected to provide benefits in dogs. Previous studies of GOS in dogs have involved dogs with similar rearing conditions and diets, which may have biased the results. We conducted an open study of 26 healthy dogs kept in households with diverse rearing environments in order to evaluate how the intake of a GOS-containing syrup affects the intestinal microbiota and its metabolites. Each dog was fed 1.2-4.8 g of the GOS-containing syrup (GOS 0.5-2.0 g equivalent) for 8 weeks. Fecal microbiota, fecal concentrations of organic acids and putrefactive products, fecal odor, and serum uremic toxin concentrations were evaluated before intake (0 weeks), during the 8-week intake period (4 and 8 weeks), and 4 weeks after intake (12 weeks). The activity of N-benzoyl-DL-arginine peptidase in dental plaque, which may be associated with periodontal disease, was evaluated at 0 and 8 weeks. Continuous intake of GOS resulted in changes in fecal microbiota, with a particularly marked increase in the abundance of Megamonas, which produces propionic acid. Other findings included a significant increase in the fecal acetic, propionic, and n-butyric acid concentrations. Additionally, significant decreases in fecal odor, fecal phenol concentration, and serum indoxyl sulfate concentration. Intake of GOS was also associated with a significant decrease in N-benzoyl-DL-arginine peptidase activity in dental plaques. These results suggest that continuous intake of GOS may contribute to canine health.

Lactic acid bacteria (LAB) are commonly used in fermented foods, and some LAB modulate the immune response. We aimed to investigate the mechanism by which LAB isolates from fermented Brassica rapa L. induce the production of anti-inflammatory interleukin (IL)-10 by the murine spleen and RAW264 cells. Spleen cells from BALB/c mice or the mouse macrophage cell line RAW264 were cultured with heat-killed LAB isolated from fermented B. rapa L., and the IL-10 level in the supernatant was measured. Latilactobacillus curvatus K4G4 provided the most potent IL-10 induction among 13 isolates. Cell wall components of K4G4 failed to induce IL-10, while treatment of the bacteria with RNase A under a high salt concentration altered K4G4 induction of IL-10 by spleen cells. In general, a low salt concentration diminished the IL-10 induction by all strains, including K4G4. In addition, chloroquine pretreatment and knock down of toll-like receptor 7 through small interfering RNA suppressed K4G4 induction of IL-10 production by RAW264 cells. Our results suggest that single-stranded RNA from K4G4 is involved, via endosomal toll-like receptor 7, in the induction of IL-10 production by macrophages. K4G4 is a promising candidate probiotic strain that modulates the immune response by inducing IL-10 from macrophages.