Probiotic Consortia and Their Metabolites Ameliorate the Symptoms of Inflammatory Bowel Diseases in a Colitis Mouse Model. Microbiology spectrum Inflammatory bowel disease (IBD) has become a global public health problem. Although the pathogenesis of the disease is unknown, a potential association between the gut microbiota and inflammatory signatures has been established. Probiotics, especially or , are orally taken as food supplements or microbial drugs by patients with IBD or gastrointestinal disorders due to their safety, efficacy, and power to restore the gut microenvironment. In the current study, we investigated the comprehensive effects of probiotic bacterial consortia consisting of Lactobacillus reuteri, Lactobacillus gasseri, Lactobacillus acidophilus ( spp.), and Bifidobacterium lactis ( spp.) or their metabolites in a dextran sodium sulfate (DSS)-induced colitis mouse model. Our data demonstrate that probiotic consortia not only ameliorate the disease phenotype but also restore the composition and structure of the gut microbiota. Moreover, the effect of probiotic consortia is better than that of any single probiotic strain. The results also demonstrate that mixed fermentation metabolites are capable of ameliorating the symptoms of gut inflammation. However, the administration of metabolites is not as effective as probiotic consortia with respect to phenotypic characteristics, such as body weight, disease activity index (DAI), and histological score. In addition, mixed metabolites led only to changes in intestinal flora composition. In summary, probiotic consortia and metabolites could exert protective roles in the DSS-induced colitis mouse model by reducing inflammation and regulating microbial dysbiosis. These findings from the current study provide support for the development of probiotic-based microbial products as an alternative therapeutic strategy for IBD. IBD is a chronic nonspecific inflammatory disease. IBD is characterized by a wide range of lesions, often involving the entire colon, and is characterized mainly by ulcers and erosions of the colonic mucosa. In the present study, we investigated the efficacy of probiotics on the recovery of gut inflammation and the restoration of gut microecology. We demonstrate that probiotic consortia have a superior effect in inhibiting inflammation and accelerating recovery compared with the effects observed in the control group or groups administered with a single strain. These results support the utilization of probiotic consortia as an alternative therapeutic approach to treat IBD. 10.1128/spectrum.00657-22

Probiotic Supplementation Improves Cognitive Function and Mood with Changes in Gut Microbiota in Community-Dwelling Older Adults: A Randomized, Double-Blind, Placebo-Controlled, Multicenter Trial. Kim Chong-Su,Cha Lina,Sim Minju,Jung Sungwoong,Chun Woo Young,Baik Hyun Wook,Shin Dong-Mi The journals of gerontology. Series A, Biological sciences and medical sciences Probiotics have been proposed to ameliorate cognitive impairment and depressive disorder via the gut-brain axis in patients and experimental animal models. However, the beneficial role of probiotics in brain functions of healthy older adults remains unclear. Therefore, a randomized, double-blind, and placebo-controlled multicenter trial was conducted to determine the effects of probiotics on cognition and mood in community-dwelling older adults. Sixty-three healthy elders (≥65 years) consumed either placebo or probiotics containing Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI for 12 weeks. The gut microbiota was analyzed using 16S rRNA sequencing and bioinformatics. Brain functions were measured using the Consortium to Establish a Registry for Alzheimer's disease, Satisfaction with life scale, stress questionnaire, Geriatric depression scale, and Positive affect and negative affect schedule. Blood brain-derived neurotrophic factor (BDNF) was determined using enzyme-linked immunosorbent assay. Relative abundance of inflammation-causing gut bacteria was significantly reduced at Week 12 in the probiotics group (p < .05). The probiotics group showed greater improvement in mental flexibility test and stress score than the placebo group (p < .05). Contrary to placebo, probiotics significantly increased serum BDNF level (p < .05). Notably, the gut microbes significantly shifted by probiotics (Eubacterium and Clostridiales) showed significant negative correlation with serum BDNF level only in the probiotics group (RS = -0.37, RS = -0.39, p < .05). In conclusion, probiotics promote mental flexibility and alleviate stress in healthy older adults, along with causing changes in gut microbiota. These results provide evidence supporting health-promoting properties of probiotics as a part of healthy diet in the older adults. 10.1093/gerona/glaa090

Causal Relationship Between Gut Microbiota and Autoimmune Diseases: A Two-Sample Mendelian Randomization Study. Xu Qian,Ni Jing-Jing,Han Bai-Xue,Yan Shan-Shan,Wei Xin-Tong,Feng Gui-Juan,Zhang Hong,Zhang Lei,Li Bin,Pei Yu-Fang Frontiers in immunology Background:Growing evidence has shown that alterations in gut microbiota composition are associated with multiple autoimmune diseases (ADs). However, it is unclear whether these associations reflect a causal relationship. Objective:To reveal the causal association between gut microbiota and AD, we conducted a two-sample Mendelian randomization (MR) analysis. Materials and Methods:We assessed genome-wide association study (GWAS) summary statistics for gut microbiota and six common ADs, namely, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, type 1 diabetes (T1D), and celiac disease (CeD), from published GWASs. Two-sample MR analyses were first performed to identify causal bacterial taxa for ADs in discovery samples. Significant bacterial taxa were further replicated in independent replication outcome samples. A series of sensitivity analyses was performed to validate the robustness of the results. Finally, a reverse MR analysis was performed to evaluate the possibility of reverse causation. Results:Combining the results from the discovery and replication stages, we identified one causal bacterial genus, . A higher relative abundance of the genus was associated with a higher risk of T1D [odds ratio (OR): 1.605; 95% CI, 1.339-1.922; = 4.19 × 10] and CeD (OR: 1.401; 95% CI, 1.139-1.722; = 2.03 × 10), respectively. Further sensitivity analyses validated the robustness of the above associations. The results of reverse MR analysis showed no evidence of reverse causality from T1D and CeD to the genus. Conclusion:This study implied a causal relationship between the genus and T1D and CeD, thus providing novel insights into the gut microbiota-mediated development mechanism of ADs. 10.3389/fimmu.2021.746998