AIM： To examine the effect of Eubacteriuro Iiroosuro （E.Iiroosuro） on colonic epithelial cell line in vitro, and to evaluate the effect of E.limosum on experimental colitis.METHODS： E.Iimosum was inoculated anaero...AIM： To examine the effect of Eubacteriuro Iiroosuro （E.Iiroosuro） on colonic epithelial cell line in vitro, and to evaluate the effect of E.limosum on experimental colitis.METHODS： E.Iimosum was inoculated anaerobically and its metabolites were obtained. The growth stimulatory effect of the E.limosum metabolites on T84 cells was evaluated by SUDH activity, and the anti-inflammatory effect by IL-6 production. The change in mRNA of toll like receptor 4 （TLR4） was evaluated by real time PCR. Colitis was induced by feeding BALB/C mice with 2.0% dextran sodium sulfate. These mice received either 5% lyophilized E.lirnosum （n=7） or control diet （n=7）. Seven days after colitis induction, clinical and histological scores, colon length, and cecal organic acid levels were determined.RESULTS： The E.Iimosum produced butyrate, acetate, propionate, and lactate at 0.25, 1.0, 0.025 and 0.07 retool/L, respectively in medium. At this concentration, each acid had no growth stimulating activity on T84 cells; however, when these acids were mixed together at the above levels, it showed significantly high activity than control. Except for lactate, these acids significantly attenuated IL-6 production at just 0.1 mmol/L. In addition, under TNF-α stimulation, butyrate attenuated the production of TLR4 mRNA. The treatment with E.limosum significantly attenuated clinical and histological scores of colitis with an increase of cecal butyrate levels, compared with the control group.CONCLUSION： E.limosum can ameliorate experimental colonic inflammation. In part, the metabolite of E.lirnosurn, butyrate, increases mucosal integrity and shows anti-inflammatory action modulation of mucosal defense system via TLR4.展开更多
The human intestinal microbiota that comprise over 1,000 species thrive in dark and anaerobic environments.They are recognized for the production of diverse low-molecular-weight metabolites crucial to human health and...The human intestinal microbiota that comprise over 1,000 species thrive in dark and anaerobic environments.They are recognized for the production of diverse low-molecular-weight metabolites crucial to human health and diseases.Carotenoids,low-molecular-weight pigments known for their antioxidative activity,are delivered to humans through oral intake.However,it remains unclear whether human intestinal bacteria biosynthesize carotenoids as part of the in-situ microbiota.In this study,we investigated carotenoid synthesis genes in vari-ous human gut and probiotic bacteria.As a result,novel candidates,the crtM and crtN genes,were identified in the carbon monoxide-utilizing gut anaerobe Eubacterium limosum and the lactic acid bacterium Leuconostoc mesenteroides subsp.mesenteroides.These gene candidates were isolated,introduced into Escherichia coli,which synthesized a carotenoid substrate,and cultured aerobically.Structural analysis of the resulting carotenoids re-vealed that the crtM and crtN gene candidates of E.limosum and L.mesenteroides mediate the production of 4,4′-diaponeurosporene through 15-cis-4,4′-diapophytoene.Evaluation of the crtE-homologous genes in these bacteria indicated their non-functionality for C40-carotenoid production.E.limosum and L.mesenteroides,along with the known carotenogenic lactic acid bacterium Lactiplantibacillus plantarum,were observed to produce no carotenoids under strictly anaerobic conditions.The two lactic acid bacteria synthesized detectable levels of 4,4′-diaponeurosporene under semi-aerobic conditions.The findings highlight that the obligate anaerobe E.limo-sum retains aerobically functional C30-carotenoid biosynthesis genes,potentially with no immediate self-utility,suggesting an evolutionary direction in carotenoid biosynthesis.(229 words)展开更多
文摘AIM： To examine the effect of Eubacteriuro Iiroosuro （E.Iiroosuro） on colonic epithelial cell line in vitro, and to evaluate the effect of E.limosum on experimental colitis.METHODS： E.Iimosum was inoculated anaerobically and its metabolites were obtained. The growth stimulatory effect of the E.limosum metabolites on T84 cells was evaluated by SUDH activity, and the anti-inflammatory effect by IL-6 production. The change in mRNA of toll like receptor 4 （TLR4） was evaluated by real time PCR. Colitis was induced by feeding BALB/C mice with 2.0% dextran sodium sulfate. These mice received either 5% lyophilized E.lirnosum （n=7） or control diet （n=7）. Seven days after colitis induction, clinical and histological scores, colon length, and cecal organic acid levels were determined.RESULTS： The E.Iimosum produced butyrate, acetate, propionate, and lactate at 0.25, 1.0, 0.025 and 0.07 retool/L, respectively in medium. At this concentration, each acid had no growth stimulating activity on T84 cells; however, when these acids were mixed together at the above levels, it showed significantly high activity than control. Except for lactate, these acids significantly attenuated IL-6 production at just 0.1 mmol/L. In addition, under TNF-α stimulation, butyrate attenuated the production of TLR4 mRNA. The treatment with E.limosum significantly attenuated clinical and histological scores of colitis with an increase of cecal butyrate levels, compared with the control group.CONCLUSION： E.limosum can ameliorate experimental colonic inflammation. In part, the metabolite of E.lirnosurn, butyrate, increases mucosal integrity and shows anti-inflammatory action modulation of mucosal defense system via TLR4.
文摘The human intestinal microbiota that comprise over 1,000 species thrive in dark and anaerobic environments.They are recognized for the production of diverse low-molecular-weight metabolites crucial to human health and diseases.Carotenoids,low-molecular-weight pigments known for their antioxidative activity,are delivered to humans through oral intake.However,it remains unclear whether human intestinal bacteria biosynthesize carotenoids as part of the in-situ microbiota.In this study,we investigated carotenoid synthesis genes in vari-ous human gut and probiotic bacteria.As a result,novel candidates,the crtM and crtN genes,were identified in the carbon monoxide-utilizing gut anaerobe Eubacterium limosum and the lactic acid bacterium Leuconostoc mesenteroides subsp.mesenteroides.These gene candidates were isolated,introduced into Escherichia coli,which synthesized a carotenoid substrate,and cultured aerobically.Structural analysis of the resulting carotenoids re-vealed that the crtM and crtN gene candidates of E.limosum and L.mesenteroides mediate the production of 4,4′-diaponeurosporene through 15-cis-4,4′-diapophytoene.Evaluation of the crtE-homologous genes in these bacteria indicated their non-functionality for C40-carotenoid production.E.limosum and L.mesenteroides,along with the known carotenogenic lactic acid bacterium Lactiplantibacillus plantarum,were observed to produce no carotenoids under strictly anaerobic conditions.The two lactic acid bacteria synthesized detectable levels of 4,4′-diaponeurosporene under semi-aerobic conditions.The findings highlight that the obligate anaerobe E.limo-sum retains aerobically functional C30-carotenoid biosynthesis genes,potentially with no immediate self-utility,suggesting an evolutionary direction in carotenoid biosynthesis.(229 words)
