Protective effects of Bifi dobacterium breve on imiquimod-induced psoriasis in mice through secondary bile acid production and FXR-TLR4/NF-κB pathway

This study aimed to evaluate the effects of Bifi dobacterium breve CCFM683 on psoriasis and to investigate the underlying mechanisms.B.breve CCFM683 significantly ameliorated psoriasis in mice as well as elevated the deoxycholic acid(DCA)and lithocholic acid(LCA)in the colon compared with those of the imiquimod(IMQ)-treated mice.Meanwhile,B.breve CCFM683 increased the relative abundance of DCA-producing Lachnoclostridium and diminished the harmful Desulfovibrio and Prevotellaceae UCG001.Additionally,the farnesoid X receptor(FXR)in the skin was activated and the expression of the Toll-like receptor 4(TLR4)/nuclear factor kappa-B(NF-κB)pathway was inhibited,and the downstream interleukin(IL)-17 and tumor necrosis factor(TNF)-αwere downregulated whereas IL-10 was up-regulated.Moreover,the subsequent hyperproliferation of keratinocytes and the dysfunction of the epidermal barrier were improved.In conclusion,CCFM683 administration ameliorated IMQ-induced psoriasis via modulating gut microbiota,promoting the DCA production,regulating the FXR-TLR4/NF-κB pathway,diminishing proinflammatory cytokines,and regulating keratinocytes and epidermal barrier.These findings may be conducive to elucidating the mechanism for probiotics to ameliorate psoriasis and to promote its clinical trials in skin disease.

Limosilactobacillus mucosae FZJTZ26M3 prevents NAFLD in mice through modulation of lipid metabolism and gut microbiota dysbiosis

Lactobacillus are considered promising therapeutic methods for nonalcoholic fatty liver disease(NAFLD).The effects of two strains of Ltmosilactobacillus mucosae on NAFLD were investigated in this study.Fourweek-old male C57BL/6J mice were divided into 4 groups(n=8 per group,Control,Model,FZJTZ26M3,FGSYC17L3).L.mucosae FZJTZ26M3 reduced the mice 's body weight,liver weight,and adipose tissue weight after 12 weeks of therapy.According to serum analysis,total cholesterol,triacylglycerol,and low-density lipoprotein cholesterol significantly decreased after L.mucosae FZJTZ26M3 intervention.Liver pathology showed that L.mucosae FZJTZ26M3 was effective to ameliorate lipid deposition in NAFLD mice.Additionally,the expression of the gene related to lipid metabolism in the liver and adipose tissue was analyzed,and the results indicated that L.mucosae FZJTZ26M3 could alleviate NAFLD by regulating lipid metabolism.Furthermore,the results of 16S rRNA gene sequencing revealed a drop in the relative abundance of Ruminococcaceae,which is linked to inflammation,but the relative abundance of a potential probiotic Akkermansia significantly increased after L.mucosae FZJTZ26M3 intervention.Generally,L.mucosae FZJTZ26M3 could be a candidate to prevent NAFLD.

Changes in the colon microbiota and intestinal cytokine gene expression following minimal intestinal surgery

AIM: To investigate the impact of minor abdominal surgery on the caecal microbial population and on markers of gut inflammation.METHODS: Four week old piglets were randomly allocated to a no-surgery "control" group(n = 6) or a "transection surgery" group(n = 5).During the transection surgery procedure, a conventional midline incision of the lower abdominal wall was made and the small intestine was transected at a site 225 cm proximal to the ileocaecal valve, a 2 cm segment was removed and the intestine was re-anastomosed.Piglets received a polymeric infant formula diet throughout the study period and were sacrificed at two weeks post-surgery.Clinical outcomes including weight, stool consistency and presence of stool fat globules were monitored.High throughput DNA sequencing of colonic content was used to detect surgery-relateddisturbances in microbial composition at phylum, family and genus level.Diversity and richness estimates were calculated for the control and minor surgery groups.As disturbances in the gut microbial community are linked to inflammation we compared the gene expression of key inflammatory cytokines(TNF, IL1 B, IL18, IL12, IL8, IL6 and IL10) in ileum, terminal ileum and colon mucosal extracts obtained from control and abdominal surgery groups at two weeks post-surgery.RESULTS: Changes in the relative abundance of bacterial species at family and genus level were confined to bacterial members of the Proteobacteria and Bacteroidetes phyla.Family level compositional shifts included a reduction in the relative abundance of Enterobacteriaceae(22.95 ± 5.27 vs 2.07 ± 0.72, P < 0.01), Bacteroidaceae(2.54 ± 0.56 vs 0.86 ± 0.43, P < 0.05) and Rhodospirillaceae(0.40 ± 0.14 vs 0.00 ± 0.00, P < 0.05) following transection surgery.Similarly, at the genus level, changes associated with transection surgery were restricted to members of the Proteobacteria and Bacteroidetes phyla and included decreased relative abundance of Enterobacteriaceae(29.20 ± 6.74 vs 2.88 ± 1.08, P < 0.01), Alistipes(4.82 ± 1.73 vs 0.18 ± 0.13, P < 0.05) and Thalassospira(0.53 ± 0.19 vs 0.00 ± 0.00, P < 0.05).Surgeryassociated microbial dysbiosis was accompanied by increased gene expression of markers of inflammation.Within the ileum IL6 expression was decreased(4.46 ± 1.60 vs 0.24 ± 0.06, P < 0.05) following transection surgery.In the terminal ileum, gene expression of TNF was decreased(1.51 ± 0.13 vs 0.80 ± 0.16, P < 0.01) and IL18(1.21 ± 0.18 vs 2.13 ± 0.24, P < 0.01), IL12(1.04 ± 0.16 vs 1.82 ± 0.32, P < 0.05) and IL10(1.04 ± 0.06 vs 1.43 ± 0.09, P < 0.01) gene expression increased following transection surgery.Within the colon, IL12(0.72 ± 0.13 vs 1.78 ± 0.28, P < 0.01) and IL10(0.98 ± 0.02 vs 1.95 ± 0.14, P < 0.01) gene expression were increased following transection surgery.CONCLUSION: This study suggests that minor abdominal surgery in infants, results in long-term alteration of the colonic microbial composition and persistent gastrointestinal inflammation.