1,720,994 research outputs found
Co-administration of Lactobacillus gasseri KBL697 and tumor necrosis factor-alpha inhibitor infliximab improves colitis in mice
No full textInflammatory bowel disease (IBD) refers to disorders involving chronic inflammation of the gastrointestinal tract. Well-established treatments for IBD have not yet to be suggested. To address this gap, we investigated the effects of co-administration of Lactobacillus gasseri (L. gasseri) KBL697 and infliximab (IFX), the first approved tumor necrosis factor (TNF)-alpha inhibitor, on the dextran sodium sulfate-induced colitis mouse model. 2 × 10(9) colony-forming units/g of L. gasseri KBL697 were administered to seven-week-old female C57BL/6J mice daily by oral gavage. On day three, IFX (5 mg/kg) suspended in 1 × PBS (200 µL) was intravenously injected in the IFX-treated group and all mice were sacrificed on day nine. Co-administration of L. gasseri KBL697 and IFX improved colitis symptoms in mice, including body weight, disease activity index, colon length, and histology score. Additionally, pro-inflammatory cytokines, such as interferon-gamma, interleukin (IL)-2, IL-6, IL-17A, and TNF were significantly decreased, while IL-10, an anti-inflammatory cytokine, was increased. Expression levels of tight junction genes and CD4 + CD25 + Foxp3 + T regulatory cells in the mesenteric lymph nodes were synergistically upregulated with the combined treatment. Furthermore, co-administered mice displayed altered cecum microbial diversity and composition with increases in the genus Prevotella. Related changes in the predicted amino and nucleic acid metabolic pathways were also evident, along with increased acetate and butyrate level. Therefore, the synergistic effect of L. gasseri KBL697 and IFX co-administration is a possible method of prevention and treatment for IBD
Vaginal lactobacilli inhibit growth and hyphae formation of Candida albicans
No full textLactobacillus species are the predominant vaginal microbiota found in healthy women of reproductive age and help to prevent pathogen infection by producing lactic acid, H2O2 and anti-microbial compounds. Identification of novel vaginal Lactobacillus isolates that exhibit efficient colonisation and secrete anti-Candida factors is a promising strategy to prevent vulvovaginal candidiasis. The azole antifungal agents used to treat vulvovaginal candidiasis elicit adverse effects such as allergic responses and exhibit drug interactions. Candida strains with resistance to antifungal treatments are often reported. In this study, we isolated Lactobacillus species from healthy Korean women and investigated their antifungal effects against C. albicans in vitro and in vivo. Lactobacillus conditioned supernatant (LCS) of L. crispatus and L. fermentum inhibited C. albicans growth in vitro. A Lactobacillus-derived compound, which was not affected by proteolytic enzyme digestion and heat inactivation, inhibited growth and hyphal induction of C. albicans after adjustment to neutral pH. Combination treatment with neutral LCSs of L. crispatus and L. fermentum effectively inhibited propagation of C. albicans in a murine in vivo model of vulvovaginal candidiasis.Y
Sputum Bacterial Metacommunities in Distinguishing Heterogeneity in Respiratory Health and Disease
No full textBackground and ObjectiveCluster-based analysis, or community typing, has been attempted as a method for studying the human microbiome in various body niches with the aim of reducing variations in the bacterial composition and linking the defined communities to host health and disease. In this study, we have presented the bacterial subcommunities in the healthy and the diseased population cohorts and have assessed whether these subcommunities can distinguish different host health conditions. MethodsWe performed community typing analysis on the sputum microbiome dataset obtained from a healthy Korean twin-family cohort (n = 202) and an external chronic obstructive pulmonary disease (COPD) cohort (n = 324) and implemented a networks analysis to investigate the associations of bacterial metacommunities with host health parameters and microbial interactions in disease. ResultsThe analysis of the sputum microbiome of a healthy Korean cohort revealed high levels of interindividual variation, which was driven by two dominant bacteria: Neisseria and Prevotella. Community typing of the cohort samples identified three metacommunities, namely, Neisseria 1 (N1), Neisseria 2 (N2), and Prevotella (P), each of which showed different functional potential and links to host traits (e.g., triglyceride levels, waist circumference, and levels of high-sensitivity C-reactive protein). In particular, the Prevotella-dominant metacommunity showed a low-community diversity, which implies an adverse health association. Network analysis of the healthy twin cohort illustrated co-occurrence of Prevotella with pathogenic anaerobic bacteria; this bacterial cluster was negatively associated with high-density lipoproteins but positively correlated with waist circumference, blood pressure, and pack-years. Community typing of the external COPD cohort identified three sub-metacommunities: one exclusively comprising healthy subjects (HSs) and the other two (CS1 and CS2) comprising patients. The two COPD metacommunities, CS1 and CS2, showed different abundances of specific pathogens, such as Serratia and Moraxella, as well as differing functional potential and community diversity. Network analysis of the COPD cohort showed enhanced bacterial coexclusions in the CS metacommunities when compared with HS metacommunity. ConclusionOverall, our findings point to a potential association between pulmonary Prevotella and host health and disease, making it possible to implement community typing for the diagnosis of heterogenic respiratory disease.Y
Revisiting the role of Akkermansia muciniphila as a therapeutic bacterium
No full textDespite a short history since its first isolation, Akkermansia muciniphila has been extensively studied in relation to its effects on human metabolism. A recent human intervention study also demonstrated that the bacterium is safe to use for therapeutic purposes. The best-known effects of A. muciniphila in human health and disease relate to its ability to strengthen gut integrity, modulate insulin resistance, and protect the host from metabolic inflammation. A further molecular mechanism, induction of GLP-1 secretion through ICAM-2 receptor, was recently discovered with the identification of a new bacterial protein produced by A. muciniphila. However, other studies have suggested a detrimental role for A. muciniphila in specific host immune settings. Here, we evaluate the molecular, mechanistic effects of A. muciniphila in host health and suggest some of the missing links to be connected before the organism should be considered as a next-generation biotherapeutic agent
Prevotella as a Hub for Vaginal Microbiota under the Influence of Host Genetics and Their Association with Obesity
No full textWhile the vaginal ecosystem is maintained through mutualistic relationships between the host and the vaginal bacteria, the effect of host genetics on the vaginal microbiota has not been well characterized. We examined the heritability of vaginal microbiota and its association with obesity in 542 Korean females, including 222 monozygotic and 56 dizygotic twins. The vaginal microbiota significantly varied depending on host menopausal status and bacterial vaginosis. Lactobacillus and Prevotella, whose relative abundances are strongly associated with bacterial vaginosis, were the most heritable bacteria among the beneficial and potentially pathogenic vaginal microbiota, respectively. Candidate gene analysis revealed an association between genetic variants of interleukin-5 and the abundance of Prevotella sp. Furthermore, host obesity significantly increased the diversity of the vaginal microbiota in association with Prevotella. Our results provide insight into the effect of host genetics on the vaginal microbiota and their association with both vaginal and non-vaginal health.Y
Complete Genome Sequence of Lactobacillus jensenii Strain SNUV360, a Probiotic for Treatment of Bacterial Vaginosis Isolated from the Vagina of a Healthy Korean Woman
No full textABSTRACT
Lactobacillus jensenii
SNUV360 is a potential probiotic strain that shows antimicrobial activity for the treatment of bacterial vaginosis. Here, we present the complete genomic sequence of
L. jensenii
SNUV360, isolated from a vaginal sample from a healthy Korean woman. Analysis of the sequence may provide insight into its functional activity.
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Complete Genome Sequence of the Plasmid-Bearing Lactobacillus fermentum Strain SNUV175, a Probiotic for Women’s Health Isolated from the Vagina of a Healthy South Korean Woman
No full textABSTRACT
Lactobacillus fermentum
SNUV175 has been identified as a probiotic strain that inhibits pathogenic microorganisms related to women’s health. We present the complete genomic sequence of the strain
L. fermentum
SNUV175 isolated from the vagina of a South Korean woman. This genomic information may provide insight into the functional activity of this strain.
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Wnt-activating human skin organoid model of atopic dermatitis induced by Staphylococcus aureus and its protective effects by Cutibacterium acnes
No full textA recently developed human PSC-derived skin organoid model has opened up new avenues for studying skin development, diseases, and regeneration. The current model has limitations since the generated organoids are enclosed, circular aggregates with an inside-out morphology with unintended off-target development of cartilage. Here, we first demonstrated that Wnt signaling activation resulted in larger organoids without off-target cartilage. We optimized further using an air-liquid interface (ALI) culture method to recapitulate structural features representative of human skin tissue. Finally, we used the ALI-skin organoid platform to model atopic dermatitis by Staphylococcus aureus (SA) colonization and infection. SA infection led to a disrupted skin barrier and increased production of epidermal- and dermal-derived inflammatory cytokines. Additionally, we found that pre-treatment with Cutibacterium acnes had a protective effect on SA-infected organoids. Thus, this ALI-skin organoid platform may be a useful tool for modeling human skin diseases and evaluating the efficacy of novel therapeutics
Bile salt hydrolase-mediated inhibitory effect of Bacteroides ovatus on growth of Clostridium difficile
No full textClostridium difficile infection (CDI) is one of the most common nosocomial infections. Dysbiosis of the gut microbiota due to consumption of antibiotics is a major contributor to CDI. Recently, fecal microbiota transplantation (FMT) has been applied to treat CDI. However, FMT has important limitations including uncontrolled exposure to pathogens and standardization issues. Therefore, it is necessary to evaluate alternative treatment methods, such as bacteriotherapy, as well as the mechanism through which beneficial bacteria inhibit the growth of C. difficile. Here, we report bile acid-mediated inhibition of C. difficile by Bacteroides strains which can produce bile salt hydrolase (BSH). Bacteroides strains are not commonly used to treat CDI; however, as they comprise a large proportion of the intestinal microbiota, they can contribute to bile acid-mediated inhibition of C. difficile. The inhibitory effect on C. difficile growth increased with increasing bile acid concentration in the presence of Bacteroides ovatus SNUG 40239. Furthermore, this inhibitory effect on C. difficile growth was significantly attenuated when bile acid availability was reduced by cholestyramine, a bile acid sequestrant. The findings of this study are important due to the discovery of a new bacterial strain that in the presence of available bile acids inhibits growth of C. difficile. These results will facilitate development of novel bacteriotherapy strategies to control CDI.N
The effect of heritability and host genetics on the gut microbiota and metabolic syndrome
No full textObjective Metabolic syndrome (MetS) arises from complex interactions between host genetic and environmental factors. Although it is now widely accepted that the gut microbiota plays a crucial role in host metabolism, current knowledge on the effect of host genetics on specific gut microbes related to MetS status remains limited. Here, we investigated the links among host genetic factors, gut microbiota and MetS in humans. Design We characterised the gut microbial community composition of 655 monozygotic (n=306) and dizygotic (n=74) twins and their families (n=275), of which approximately 18% (121 individuals) had MetS. We evaluated the association of MetS status with the gut microbiota and estimated the heritability of each taxon. For the MetS-related and heritable taxa, we further investigated their associations with the apolipoprotein A-V gene (APOA5) single nucleotide polymorphism (SNP) rs651821, which is known to be associated with triglyceride levels and MetS. Results Individuals with MetS had a lower gut microbiota diversity than healthy individuals. The abundances of several taxa were associated with MetS status; Sutterella, Methanobrevibacter and Lactobacillus were enriched in the MetS group, whereas Akkermansia, Odoribacter and Bifidobacterium were enriched in the healthy group. Among the taxa associated with MetS status, the phylum Actinobacteria, to which Bifidobacterium belongs, had the highest heritability (45.7%). Even after adjustment for MetS status, reduced abundances of Actinobacteria and Bifidobacterium were significantly linked to the minor allele at the APOA5 SNP rs651821. Conclusions Our results suggest that an altered microbiota composition mediated by a specific host genotype can contribute to the development of MetS.N
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