Lactiplantibacillus plantarum Lac16 Attenuates Enterohemorrhagic Escherichia coli O157:H7 Infection by Inhibiting Virulence Traits and Improving Intestinal Epithelial Barrier Function.

Large-scale use of antimicrobials in agriculture and medicine contributes to antibiotic residues in raw foods, the spread of antimicrobial resistance (AMR) and drug pollution, which seriously threatens human health and imposes significant economic burdens on society, suggesting the need for novel therapeutic options that prevent or control zoonoses. In this study, four probiotics were selected to assess their capability to alleviate pathogen-induced damage. Results showed that a simulated gastrointestinal juice and bile tolerated L. plantarum Lac16 with high lactic acid secretion can significantly inhibit the growth of multiple zoonotic pathogens. Lac16 also significantly inhibited the biofilm formation and mRNA expression of virulence traits (genes related to virulence, toxins, flagella biogenesis and motility, antibiotic resistance, biofilm formation and AI-2 quorum sensing) of enterohemorrhagic E. coli O157:H7 (EHEC). Furthermore, Lac16 and Lac26 significantly protected C. elegans against zoonotic pathogen-induced (EHEC, S. typhimurium, C. perfringens) deaths. Moreover, Lac16 significantly promoted epithelial repair and ameliorated lipopolysaccharide (LPS)-induced intestinal epithelial apoptosis and barrier dysfunction by activating the Wnt/ß-catenin signaling pathway, and markedly reduced LPS-induced inflammatory responses by inhibiting the TLR4/MyD88 signaling pathway. The present results indicate that Lac16 attenuates enterohemorrhagic E. coli infection-induced damage by inhibiting key virulence traits of E. coli, promoting epithelial repair and improving intestinal epithelial barrier function, which may be mediated by the activated Wnt/ß-catenin signaling pathway and the inhibited TLR4/MyD88 signaling pathway of the intestinal epithelium.

Bacillus amyloliquefaciens SC06 attenuated high-fat diet induced anxiety-like behavior and social withdrawal of male mice by improving antioxidant capacity, intestinal barrier function and modulating intestinal dysbiosis.

Anxiety-like behavior and social withdrawal induced by obesity and oxidative stress are significant health concerns in contemporary society. Our previously study found that Bacillus amyloliquefaciens SC06 (SC06) decreased the body weight of high-fat diet (HFD)-fed male mice and protected porcine intestinal epithelial cells against oxidative stress. The present study further investigated the effect of SC06 on HFD-induced obesity, anxiety-like behavior and social withdrawal of male mice and explored its mechanism. Results showed that SC06 significantly decreased HFD-induced obesity as evidenced by the decreased body weight, weight of liver and epididymal fat. Meanwhile, SC06 attenuated the anxiety-like behavior of HFD-fed male mice as illustrated by the more exploration time in both the open arms of elevated plus maze and the central area of open field and the reversed their social withdrawal tested in the three-chamber social choice task. SC06 also reduced reactive oxygen species (ROS) concentration and normalized the mitochondrial morphology in the hippocampus. SC06 reduced the systemic inflammation and increased the expression of intestinal tight junctions (ZO-1 and Claudin1). Furthermore, SC06 also altered the microbial diversity and composition, and decreased Firmicutes to Bacteroidetes ratio of HFD-fed male mice. These findings suggest SC06 attenuate HFD-induced anxiety-like behavior and social withdrawal of male mice by attenuating hippocampal oxidation stress, systemic inflammation, dysbiosis and improving intestinal barrier function.

RNA-sequencing analysis of bisphenol A biodegradation by white-rot fungus Phanerochaete sordida YK-624.

Bisphenol A (BPA) is a representative example of an endocrine-disrupting chemical. It is one of the most produced chemical substances in the world, but it causes harmful effects in organisms, such that the effective degradation of BPA is critical. The white-rot fungus Phanerochaete sordida YK-624 has been shown to effectively degrade BPA under ligninolytic and non-ligninolytic conditions. However, it is still unclear what kinds of enzymes are involved in BPA degradation. To explore the mechanism of BPA degradation, the present study analysed the functional genes of P. sordida YK-624 using RNA-sequencing (RNA-Seq). Oxidation-reduction process and metabolic pathway were enriched under ligninolytic and non-ligninolytic conditions by Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. It is suggested that BPA might be used as a carbon source by P. sordida YK-624. Lignin peroxidase and cytochrome P450 were detected in upregulated differentially expressed genes (DEGs). The lignin-degrading enzyme lignin peroxidase and the intracellular cytochrome P450 system were involved in BPA degradation by P. sordida YK-624, respectively. Furthermore, quantitative real-time PCR (qPCR) was used to validate the reliability of the RNA-Seq results. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03298-w.

Bacillus amyloliquefaciens SC06 alleviates the obesity of ob/ob mice and improves their intestinal microbiota and bile acid metabolism.

Dietary interventions with probiotics have been widely reported to be effective in regulating obesity, and the intestinal microbiota is considered to be an important environmental factor. However, few reports focus on the interactions of microbiota-metabolites-phenotypic variables in ob/ob mice, and they have not been characterized in great detail. In this study, we investigated the effects of Bacillus amyloliquefaciens SC06 on obesity, the intestinal microbiota and the bile acid metabolism of ob/ob mice using biochemical testing, histochemical staining, high-throughput sequencing of the 16S rRNA gene, LC-MS/MS analysis and qRT-PCR. The results showed that SC06 ameliorated the fat mass percentage, hepatic steatosis and liver lipid metabolism disorders and reshaped the gut microbiota and metabolites in male ob/ob mice, specifically deceasing f_S24-7, p_TM7, s_Alistipes massiliensis, f_Rikenellaceae, f_Prevotellaceae, f_Lactobacillaceae, g_Alistipes, g_Flexispira, g_Lactobacillus, g_Odoribacter, g_AF12 and g_Prevotella and increasing f_Bacteroidaceae, g_Bacteroides and f_Desulfovibrionaceae. Meanwhile, SC06 treatment groups had lower ibuprofen and higher glycodeoxycholic acid and 7-dehydrocholesterol. Correlation analysis further clarified the relationships between compositional changes in the microbiota and alterations in the metabolites and phenotypes of ob/ob mice. Moreover, SC06 downregulated bile acid synthesis, export and re-absorption in the liver and increased ileum re-absorption into the blood in ob/ob mice, which may be mediated by the FXR-SHP/FGF15 signaling pathway. These results suggest that Bacillus amyloliquefaciens SC06 can ameliorate obesity in male ob/ob mice by reshaping the intestinal microbial composition, changing metabolites and regulating bile acid metabolism via the FXR signaling pathway.

Bacillus amyloliquefaciens Ameliorates H2O2-Induced Oxidative Damage by Regulating Transporters, Tight Junctions, and Apoptosis Gene Expression in Cell Line IPEC-1.

Probiotics have always been considered as a supplementary therapy for many diseases especially gut disorders. The absorption and barrier function of the gut play a vital role in the maintenance of body homeostasis. This study was to investigate the protective effects of Bacillus amyloliquefaciens SC06 (Ba) on H2O2-induced oxidative stress on intestinal porcine epithelial cells (IPEC-1) based on the level of gene expression. We demonstrated that Ba was a safe probiotic strain in the first place. Results showed that treatment with H2O2 significantly increased the mRNA expression of absorptive transporters glucose transporter 2 (GLUT2), Ala/Ser/Cys/Thr transporter 1 (ASCT1), and ASCT2 compared with the control group. Meanwhile, oxidative stress induced a significant improvement in the mRNA expression of occludin (OCLN) and caspase-3, and remarkably inhibited the expression of L-type amino acid transporter 1 (LAT1) or B cell lymphoma-2 (Bcl-2), respectively. Pretreatment with Ba dramatically reversed the disturbance induced by oxidative stress on the mRNA expression of ASCT1, ASCT2, and OCLN, which also significantly prevented H2O2-inhibited LAT1 and Bcl-2 mRNA expression. However, Ba failed to exert any significant protective effect on GLUT2 and caspase-3 mRNA expression. We concluded that pretreatment with Ba could alleviate the damage caused by oxidative stress to a certain extent and conferred a protective effect to the intestine.

Protective effect of Bacillus amyloliquefaciens against Salmonella via polarizing macrophages to M1 phenotype directly and to M2 depended on microbiota.

Bacillus amyloliquefaciens SC06 (BaSC06), a potential probiotic, plays a positive role in animal growth performance and immune function. The aim of the present study was to investigate the protective effect of BaSC06 against Salmonella infection and its association with macrophage polarization. C57BL/6 mice were fed with or without a BaSC06-containing diet before Salmonella enterica Typhimurium (ST) challenge. Results showed that BaSC06 had a protective effect against ST inoculation and induced both M1 and M2 macrophage polarization in the cecum. An in vitro co-culture model demonstrated that BaSC06 promoted M1 polarization directly, and thus increased the phagocytosis and bactericidal activity against ST. In addition, adoptive transfer of bone marrow-derived macrophages (BMDMs) stimulated by BaSC06 significantly decreased the counts of ST in the spleen. Furthermore, 16S rRNA-based analysis of cecal content showed that BaSC06 significantly increased the proportion of Verrucomicrobia and decreased Bacterodetes. Transplantation of the fecal microbiota from BaSC06-treated animals promoted M2 macrophage polarization in the cecum and significantly relieved inflammation caused by ST. In conclusion, BaSC06 polarized macrophages to the M1 type directly resulting in excellent bactericidal activity. Meanwhile, the microbiota modified by BaSC06 can induce M2 polarization which ameliorates the inflammation caused by ST.

Effects of probiotics Lactobacillus plantarum 16 and Paenibacillus polymyxa 10 on intestinal barrier function, antioxidative capacity, apoptosis, immune response, and biochemical parameters in broilers.

This study aimed to investigate the effects of Lactobacillus plantarum 16 (Lac16) and Paenibacillus polymyxa 10 (BSC10) on intestinal barrier function, antioxidative capacity, apoptosis, immune response, and biochemical parameters in broilers. A total of 540 one-day-old broiler chicks (Cobb500) were randomly allocated to three groups of 180 birds, and fed either a basal diet or a basal diet supplemented with 108 colony-forming units Lac16 or BSC10 per kilogram feed for 21 D. The results revealed that both Lac16 and BSC10 maintained ileal mucosal morphology, and BSC10 regulated the expression of barrier function-related genes. Birds fed with probiotics decreased malondialdehyde level in jejunal mucosa and serum, and the increased activities of hepatic GSH-Px and jejunal CAT were observed in BSC10 group (P < 0.05). Immunohistochemistry of Bax, Bcl-2 and proliferating cell nuclear antigen and TUNEL-immunofluorescence assay demonstrated that Lac16 and BSC10 exerted beneficial effects on cell apoptosis and proliferation, as indicated by the gene expression of down-regulated Bax and p53 as well as a significant upregulation of Bcl-2 (P < 0.05). In addition, Lac16 and BSC10 significantly increased NO production and iNOS activity in liver and jejunal mucosa, and gene expression of IFN-γ (P < 0.01), IL-6 (P < 0.05), and IL-10 (P < 0.05 and P < 0.01, respectively) in ileum mucosa, whereas markedly decreased the expression of Cox2 (P < 0.05). Furthermore, it was found that Lac16 and BSC10 significantly reduced levels of alkaline phosphatase (P < 0.05 and P < 0.01, respectively) and creatine kinase (P < 0.05). Moreover, BSC10 significantly reduced uric acid (P < 0.05) and low-density lipoprotein levels (P < 0.01). Taken together, Lac16 and BSC10 could improve intestinal and body health status of broilers by increasing intestinal barrier function, anti-oxidative capacity and immunity, and decreasing cell apoptosis with strain-specificity.

Exploring the Fecal Microbial Composition and Metagenomic Functional Capacities Associated With Feed Efficiency in Commercial DLY Pigs.

Gut microbiota has indispensable roles in nutrient digestion and energy harvesting, especially in processing the indigestible components of dietary polysaccharides. Searching for the microbial taxa and functional capacity of the gut microbiome associated with feed efficiency (FE) can provide important knowledge to increase profitability and sustainability of the swine industry. In the current study, we performed a comparative analysis of the fecal microbiota in 50 commercial Duroc × (Landrace × Yorkshire) (DLY) pigs with polarizing FE using 16S rRNA gene sequencing and shotgun metagenomic sequencing. There was a different microbial community structure in the fecal microbiota of pigs with different FE. Random forest analysis identified 24 operational taxonomic units (OTUs) as potential biomarkers to improve swine FE. Multiple comparison analysis detected 8 OTUs with a significant difference or tendency toward a difference between high- and low-FE pigs (P < 0.01, q < 0.1). The high-FE pigs had a greater abundance of OTUs that were from the Lachnospiraceae and Prevotellaceae families and the Escherichia-Shigella and Streptococcus genera than low-FE pigs. A sub-species Streptococcus gallolyticus subsp. gallolyticus could be an important candidate for improving FE. The functional capacity analysis found 18 KEGG pathways and CAZy EC activities that were different between high- and low-FE pigs. The fecal microbiota in high FE pigs have greater functional capacity to degrade dietary cellulose, polysaccharides, and protein and may have a greater abundance of microbes that can promote intestinal health. These results provided insights for improving porcine FE through modulating the gut microbiome.

Glycyrrhizin Attenuates Salmonella enterica Serovar Typhimurium Infection: New Insights Into Its Protective Mechanism.

Glycyrrhizin (GL), a triterpenoid glycoside, serves important functions in various biological activities, including antiviral and antitumor immune responses. However, the anti-inflammatory effects of GL on Salmonella enterica serovar Typhimurium (ST)-induced injury in mice and the mechanisms underlying the protection of GL are poorly understood. Here, we investigated the effects of GL on host immune responses against ST infection in mice. A phenotypic analysis using hematoxylin and eosin (H&E) staining and transmission electron microscopy showed that GL relieved ST-induced weight loss and intestinal mucosal injury. A colonization assay showed that GL significantly reduced ST colonization in the ileum and colon and translocation to the liver and spleen. An antibacterial activity assay and real-time PCR revealed that GL had no direct inhibitory impact on ST growth or virulence gene expression. ELISA showed that GL pretreatment significantly decreased proinflammatory cytokine (IFN-γ, TNF-α, IL-6) secretion and increased anti-inflammatory cytokine (IL-10) secretion in the ileum, colon and serum of ST-infected mice. Moreover, flora analysis showed that GL reduced Akkermansia, Sutterella, Prevotella and Coprococcus but enriched Parabacteroides and Anaerotruncus in the cecum of ST-infected mice. These results suggest that GL promotes the secretion of immune factors and modulates intestinal flora to prevent further ST infection. We also analyzed the effect of GL on immunocytes and found that GL promoted the phenotypic and functional maturation of murine bone marrow-derived dendritic cells (BMDCs). Flow cytometry and western blotting demonstrated that NF-κB, ERK, and p38 MAPK were required for GL-induced BMDC maturation. The above findings indicate that GL attenuates ST infection by modulating immune function and intestinal flora. This study enriches our current knowledge of GL-mediated immunological function and provides a new perspective on the prevention of Salmonella infection in animals and humans.

Solitary giant hemangioma of the humerus.

Osseous hemangiomas are mainly seen in the skull or spine and rarely occur in other bones. They are small lesions usually localized in the metaphyseal and diaphyseal regions. This article describes a rare case of a giant intraosseous hemangioma occupying nearly the whole humerus for 28 years. Initially, the patient, a 36-year-old woman, had been misdiagnosed with fibrous hyperplasia of the left humerus. We intended to curette the lesions and transplant fibula to fill the bone defect, but the initial surgical attempt could not be completed due to massive intraoperative bleeding. In the second surgery, she was treated by blocking the blood flow of the subclavian artery temporarily through a balloon catheter, curetting lesions, and filling the defect of bone with bone cement and K-wires. At 12-month follow-up, there was no evidence of local recurrence of hemangioma or loosening of bone cement. However, longer-term follow-up is needed to confirm the success of the surgery. Although hemangiomas of long bone are rare, they should be considered in the differential diagnosis of bone tumors.