Academic literature on the topic 'Blautia hansenii'

Intestinal microflora has been associated with obesity. While visceral fat is more strongly associated with cardiovascular disorder, a complication linked to obesity, than the body mass index (BMI), the association between intestinal microflora and obesity (as defined in terms of BMI) has been studied widely. However, the link between visceral fat area (VFA) and intestinal microflora has been little studied. In this study, we investigate the association between intestinal microflora and VFA and BMI using a longitudinal study on Japanese subjects with different VFA statuses (N = 767). Principal component analysis of the changes in intestinal microflora composition over the one-year study period revealed the different associations between intestinal microflora and VFA and BMI. As determined by 16S rRNA amplicon sequencing, changes in the abundance ratio of two microbial genera—Blautia and Flavonifractor—were significantly associated with VFA changes and changes in the abundance ratio of four different microbial genera were significantly associated with BMI changes, suggesting that the associated intestinal microbes are different. Furthermore, as determined by metagenomic shotgun sequences, changes in the abundance ratios of two Blautia species—Blautia hansenii and Blautia producta—were significantly and negatively associated with VFA changes. Our findings might be used to develop a new treatment for visceral fat.

Lees are a winery by-product with a fiber-rich composition that could have a potential prebiotic effect on gut microbiota. Prebiotics cannot be digested by humans but can be used by bacteria found in the large intestine. To evaluate the potential prebiotic effect of lees, they were administered to Wistar rats for 14 days. Feces were collected daily, and DNA was extracted and analyzed by shot gun sequencing. The supplementation with lees did not affect weight, food intake, or water consumption of the studied rats. It was found that lees promoted the increase of relative abundance of probiotic bacteria belonging to the Lactobacillaceae family, as well as other potentially probiotic species such as Blautia hansenii, Roseburia intestinalis, and Ruminococcus obeum. Moreover, lees supplementation also reduced the abundance of certain pathogenic bacteria. In conclusion, lees can improve the presence of beneficial bacteria in the gastrointestinal tract and can be re-valorized as a new ingredient in food formulation.

Abstract Background Changes in microbiome of the gut and decreased diversity in inflammatory bowel disease(IBD) is the subject of intense researches. The exact pathophysiological connection is lacking, but the systemic inflammation due to the microbial alterations are assumed. This study aimed to perform analysis of faecal microbiota composition simultaneously with body composition by bioelectrical impedance and nutrition habits in Crohn’s disease(CD) patients to find specific microbiota profiles connected with obesity, mesenterial fat, signs of systemic inflammation, nutritional and body composition characteristics. Methods In our prospective cohort study, CD patients were enrolled. At the inclusion, demographic and clinical data, blood, and faecal samples were obtained. Clinical disease activity was assessed by CDAI, and SES-CD. Laboratory tests were made including C-reactive protein(CRP), albumin and lipids (triglyceride, cholesterol). Faecal bacterial composition was assessed using shotgun metagenomics sequencing technique. Each patient underwent a body composition analysis via bioelectrical impedance analysis. A nutritional questionnaire was filled by each subject. Results Data of 27 CD patients with different localisation was analysed in this study (mean age was 35±11 years). According to the gut inflammation, some Blautia species correlated positively with SES-CD (p=0,004), and correlated with faecal calprotectin negatively (p=0,02), while Roseburia hominis negatively with CDAI scores(p=0,01). High CDAI scores were also associated with dysbiosis. Adlercreutzia equolifaciens and Blautia hansenii associated with triglyceride(negatively p=0,04, positively p=0,05). Firmicutes has a lower, while Bacteroidetes has a higher abundance at high cholesterol level(p=0,001, p=0,023). Lower Adlercreutzia and Lactobacillus abundance were seen in patients with high visceral fat area(p=0,05, p=0,01), while Clostridia correlated with percent body fat(p=0,025).Bifidobacterium bifidum were associated in people with low body weight or low skeletal muscle mass(p=0,01, p=0,03). Beside Clostridia, Eubacteriales also correlated with waist-hip ratio(p=0,04, p=0,04). Conclusion To our knowledge this is the first study to analyse microbiota profiles by shotgun sequencing technique in CD patients depending on body composition via bioelectrical impedance and nutrition. Changes in Blautia, Lactobacillus, Adlercreutzia, Roseburia and Bifidobacterium abundances in patients with CD and obesity highlight the importance of correlations between lipid metabolism, adipose tissue mass, and chronic inflammation. Through this, it helps to develop new therapeutic approaches, such as personalized pre- or probiotics or faecal microbiota transplantation.

We have studied the effects of aging on the fecal microbiota composition in the senescence-accelerated prone mice SAMP8 strain. We compared animals two, four, and six months old. Feces were collected at the end of each period and a genomic study was carried out on fecal DNA using the Illumina MiSeq analyzer. The Shannon diversity index showed similar values along this period and the number of species was neither affected by aging. The phylum Verrucobacteria went up with age, showing a seven-fold increase at six months, compared to two-month old mice. At the family level, changes observed between two and six months of age involved significant increases in Bacteroidaceae (q < 0.001) and strong reductions in Lactobacillaceae (q < 0.0001) and Prevotellaceae (q < 0.05); at the genus level, there was a significant reduction in probiotic Lactobacillus. At the species level, we observed an age-related reduction in Lactobacillus hayakitensis, a species involved in mucosal immune homeostasis, and in Blautia hansenii, which provides protection against Clostridium difficile infection. Interestingly, aging increases Parabacteroides goldsteiini, which is involved in the regulation of the TLR4 pathway. These results support the view that aging results in the proliferation of bacterial species that are associated with the immune deterioration of the gut mucosa.

AbstractA high-fat diet can lead to gut microbiota dysbiosis, chronic intestinal inflammation, and metabolic syndrome. Notably, resulting phenotypes, such as glucose and insulin levels, colonic crypt cell proliferation, and macrophage infiltration, exhibit sex differences, and females are less affected. This is, in part, attributed to sex hormones. To investigate if there are sex differences in the microbiota and if estrogenic ligands can attenuate high-fat diet-induced dysbiosis, we used whole-genome shotgun sequencing to characterize the impact of diet, sex, and estrogenic ligands on the microbial composition of the cecal content of mice. We here report clear host sex differences along with remarkably sex-dependent responses to high-fat diet. Females, specifically, exhibited increased abundance of Blautia hansenii, and its levels correlated negatively with insulin levels in both sexes. Estrogen treatment had a modest impact on the microbiota diversity but altered a few important species in males. This included Collinsella aerofaciens F, which we show correlated with colonic macrophage infiltration. In conclusion, male and female mice exhibit clear differences in their cecal microbial composition and in how diet and estrogens impact the composition. Further, specific microbial strains are significantly correlated with metabolic parameters.

Abstract Background Innate immunity genes have been reported to affect susceptibility to inflammatory bowel diseases (IBDs) and colitis in mice. Dectin-1, a receptor for fungal cell wall β-glucans, has been clearly implicated in gut microbiota modulation and modification of the susceptibility to gut inflammation. Here, we explored the role of Dectin-1 and Dectin-2 (another receptor for fungal cell wall molecules) deficiency in intestinal inflammation. Design Susceptibility to dextran sodium sulfate (DSS)-induced colitis was assessed in wild-type, Dectin-1 knockout (KO), Dectin-2KO, and double Dectin-1KO and Dectin-2KO (D-1/2KO) mice. Inflammation severity, as well as bacterial and fungal microbiota compositions, was monitored. Results While deletion of Dectin-1 or Dectin-2 did not have a strong effect on DSS-induced colitis, double deletion of Dectin-1 and Dectin-2 significantly protected the mice from colitis. The protection was largely mediated by the gut microbiota, as demonstrated by fecal transfer experiments. Treatment of D-1/2KO mice with opportunistic fungal pathogens or antifungal agents did not affect the protection against gut inflammation, suggesting that the fungal microbiota had no role in the protective phenotype. Amplicon-based microbiota analysis of the fecal bacterial and fungal microbiota of D-1/2KO mice confirmed the absence of changes in the mycobiota but strong modification of the bacterial microbiota. We showed that bacteria from the Lachnospiraceae family were at least partly involved in this protection and that treatment with Blautia hansenii was enough to recapitulate the protection. Conclusions Deletion of both the Dectin-1 and Dectin-2 receptors triggered a global shift in the microbial gut environment, affecting, surprisingly, mainly the bacterial population and driving protective effects in colitis. Members of the Lachnospiraceae family seem to play a central role in this protection. These findings provide new insights into the role of the Dectin receptors, which have been described to date as affecting only the fungal population, in intestinal physiopathology and in IBD.

Une dysbiose du microbiote intestinal a été identifiée comme impliquée dans la pathogenèse des maladies inflammatoires chroniques de l'intestin (MICI). Il a été démontré que les interactions hôte-bactéries affectent le développement des MICI, tandis que le rôle des interactions hôte-champignons dans les MICI sont peu décrites. Les lectines de type C sont des récepteurs impliqués dans la reconnaissance de motifs du mycobiote et font les réponses immunitaires face aux agents pathogènes fongiques. Nous avons évalué l'impact de la déficience des récepteurs Dectin-1 (D-1KO), Dectin-2 (D-2KO) et de la double déficience (D-1/2KO) dans l'inflammation intestinale. L’absence de D-1 ou D-2 n’a pas modifié la gravité de l'inflammation intestinale, tandis que les souris D-1/2KO étaient résistantes à la colite. Le rôle protecteur de D-1/2KO a été confirmé chez des souris WT ayant reçu le microbiote intestinal desD-1/2KO, suggérant que la protection était largement due au microbiote. L'analyse du microbiote des souris D-1/2KO montre que le microbiote bactérien, et en particulier la famille des Lachnospiraceae, mais pas le mycobiote, présentait une forte modification par rapport aux souris WT. Une supplémentation en Blautia hansenii a pu également assurer la protection, appuyant que cette protection était largement médiée par le microbiote bactérien. Ces résultats montrent que la déficience D-1/2 protége les souris de la colite via une modulation du microbiote intestinal bactérien
Gut microbiota dysbiosis has been identified as being involved in the pathogenesis of inflammatory bowel disease (IBD). Host-bacterial interactions have been shown to affect the development of IBD, while the role of host-fungal interactions in IBD is poorly described. C-type lectins are receptors involved in the recognition of patterns of the mycobiota and shape the immune responses to fungal pathogens. We evaluated the impact of the deficiency of the receptors Dectin-1 (D-1KO), Dectin-2 (D-2KO) and dual deficiency (D-1/2KO) in intestinal inflammation. The absence of D-1 or D-2 did not alter the severity of intestinal inflammation, whereas D-1/2KO mice were resistant to colitis. The protective role of D-1/2KO was confirmed in WT mice receiving the gut microbiota of D-1/2KO by fecal transfer, suggesting that protection was largely due to the gut microbiota. Analysis of the microbiota of D-1/2KO mice shows that the bacterial microbiota, and in particular the Lachnospiraceae family, but not the mycobiota, showed a strong change compared to the microbiota of the WT mice. Blautia hansenii supplementation was also able to provide protection, supporting that this protection was largely mediated by the bacterial microbiota and not the fungal microbiota. These results show that D-1/2KO deficiency protect mice from DSS-induced colitis via modulation of the bacterial gut microbiota