Investigating the crucial role of selected Bifidobacterium probiotic strains in preventing or reducing inflammation by affecting the autophagy pathway.

Several studies have shown that probiotics can prevent and reduce inflammation in inflammation-related diseases. However, few studies have focused on the interaction between host and probiotics in modulating the immune system through autophagy. Therefore, we aimed to investigate the preventive and/or therapeutic effects of native potential probiotic breast milk-isolated Bifidobacterium spp. (i.e. B. bifidum, B. longum, and B. infantis) on the inflammatory cascade by affecting autophagy gene expression 24 and 48 h after treatment. Autophagy genes involved in different stages of the autophagy process were selected by quantitative polymerase chain reaction (qPCR). Gene expression investigation was accomplished by exposing the human colorectal adenocarcinoma cell line (HT-29) to sonicated pathogens (1.5 × 108 bacterial CFU ml-1) and adding Bifidobacterium spp. (MOI10) before, after, and simultaneously with induction of inflammation. An equal volume of RPMI medium was used as a control. Generally, our native potential probiotic Bifidobacterium spp. can increase the autophagy gene expression in comparison with pathogen. Moreover, an increase in gene expression was observed with our probiotic strains' consumption in all stages of autophagy. Totally, our selected Bifidobacterium spp. can increase autophagy gene expression before, simultaneously, and after the inflammation induction, so they can prevent and reduce inflammation in an in vitro model of inflammation.

Ameliorating inflammation in an in vitro model by screening the anti-inflammatory and immunomodulatory roles of putative probiotics in inflammatory bowel disease.

IBD is considered a relapsing disease with relapsing phases. Probiotics are beneficial microorganisms that modulate inflammatory signaling pathways. Our aim was to identify the precise molecular effects of probiotics on inflammatory signaling pathways during the presence of inflammation. Evaluation of the expression of JAK/STAT and inflammatory genes after treatment of the HT -29 cell line with the sonicated pathogens and probiotics, simultaneously was performed by quantitative real-time polymerase chain reaction (qPCR) assay. The production of IL-6 and IL-1ß after administration of probiotics was conducted by means of cytokine assay. The probiotic cocktail resulted in the downregulation of TIRAP, IRAK4, NEMO, and RIP genes in the NF-кB pathway compared with Sonicat-treated cells. The expression of JAK/STAT genes was various after probiotic treatment. The application of probiotics has been observed to result in a notable decrease in the production of IL-6 and IL-1ß. The investigated probiotic cocktail, especially Bifidobacterium spp. showed anti-inflammatory effects on HT -29 cells via modulation of JAK/STAT and NF-кB signaling pathways. The use of probiotics with the least side effects could be considered a suitable treatment for patients with inflammatory bowel disease, even at the beginning of inflammation.

Investigation of the anti-inflammatory effects of native potential probiotics as supplementary therapeutic agents in an in-vitro model of inflammation.

BACKGROUND: IBD is considered an inflammatory disease with abnormal and exaggerated immune responses. To control the symptoms, different theraputic agents could be used, however, utilizing the agents with the least side effects could be important. Probiotics as beneficial microorganisms are one of the complementory theraputic agents that could be used to modulate inflammatory signaling pathways. In the current study, we aimed to identify the precise molecular effects of potential probiotics on signaling pathways involved in the development of inflammation. METHODS: A quantitative real-time polymerase chain reaction (qPCR) assay was used to analyze the expression of JAK /STAT (JAK1, JAK2, JAK3, TYK2, STAT1, STAT2, STAT3, STAT4, STAT5 and STAT6) and inflammatory genes (NEMO, TIRAP, IRAK, and RIP) after the HT -29 cell line treatment with the sonicated pathogens and potential probiotics. A cytokine assay was also used to evaluate IL -6 and IL -1ß production after potential probiotic treatment. RESULTS: The potential probiotic cocktail downregulated the JAK genes and TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway compared with cells that were treated with sonicated gram negative pathogens. The expression of STAT genes was different after potential probiotic treatment. The production of IL -6 and IL -1ß decreased after potential probiotic treatment. CONCLUSIONS: Considering the importance of controlling the symptoms of IBD to improve the life quality of the patients, using probiotic could be crucial. In the current study the studied native potential probiotic cocktails showed anti-inflammatory effects via modulation of JAK /STAT and NF-kB signaling pathways. This observation suggests that our native potential probiotics consumption could be useful in reducing intestinal inflammation.

The Anti-Inflammatory Effect of a Probiotic Cocktail in Human Feces Induced-Mouse Model.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract due to altered interaction between the immune system and the gut microbiota. The aim of this study was to investigate the role of a probiotic cocktail in modulating immune dysregulation induced in mice. Mice were divided into 5 groups (n = 5/group), and inflammation was induced in two separate groups by fecal microbiota transplantation (FMT) from the stool of human with IBD and dextran sulfate sodium (DSS). In the other two groups, the cocktail of Lactobacillus spp. and Bifidobacterium spp. (108CFU/kg/day) was administered daily for a total of 28days in addition to inducing inflammation. A group as a contcxsrol group received only water and food. The alteration of the selected genera of gut microbiota and the expression of some genes involved in the regulation of the inflammatory response were studied in the probiotic-treated and untreated groups by quantitative real-time PCR. The selected genera of gut microbiota of the FMT and DSS groups showed similar patterns on day 28 after each treatment. In the probiotic-treated groups, the population of the selected genera of gut microbiota normalized and the abundance of Firmicutes and Actinobacteria increased compared to the DSS and FMT groups. The expression of genes related to immune response and tight junctions was positively affected by the probiotic. Changes in the gut microbiota could influence the inflammatory status in the gut, and probiotics as a preventive or complementary treatment could improve the well-being of patients with inflammatory bowel disease symptoms.

Immunization with recombinant DcaP-like protein and AbOmpA revealed protections against sepsis infection of multi-drug resistant Acinetobacter baumannii ST2Pas in a C57BL/6 mouse model.

BACKGROUNDS: The prevalence of infections associated with multi-drug resistant (MDR) Acinetobacter baumannii is increasing worldwide. Therefore, the introduction of effective vaccines against this bacterium seems necessary. METHODS: AbOmpA and DcaP-like protein were selected as promising and putative immunogenic candidates based on previous in silico studies. Three formulations including AbOmpA, DcaP-like protein, and AbOmpA + DcaP-like protein were injected into C57BL/6 mice three times with Alum adjuvant. The specific production of IgG antibodies (e.g. total IgG, IgG1 and IgG2c) and cytokines (e.g. IL-4, IL-6, and IL-17A), were evaluated. LD50% of MDR A. baumannii ST2Pas was measured using Probit's method. After the challenge with bacteria, a decrease in bacterial loads (DLs) in the lung and spleen of mice was measured. Then serum bactericidal assay was performed to determine the function of antibodies on day 42. In addition, histopathological examinations of the spleen and lung, the number of macrophage and neutrophil, as well as the rate of lymphocyte infiltration were assessed. RESULTS: The highest level of total IgG was reported in the group immunized with DcaP-like protein on day 42. The survival rate of mice was 80% in the AbOmpA immunized group and 100% for the rest of two groups. DLs in the spleen of mice immunized with AbOmpA, DcaP-like protein, and combination form were 3.5, 3, and 3.4 Log10 (CFU/g), respectively. While in the lung, the DLs were 7.5 Log10 (CFU/g) for the AbOmpA group and 5 for the rest of two groups. The levels of IL-6, IL-4, and IL-17A were significantly decreased in all immunized groups after the bacterial challenge (except for IL-17A in the group of AbOmpA). The bactericidal effect of antibodies against DcaP-like protein was more effective. No histopathological damage was observed in the combination immunized group. The DcaP-like protein was more effective in neutrophil and macrophage deployment and decreased lymphocyte infiltration. CONCLUSION: The results of immunization with AbOmpA + DcaP-like protein induced a protective reaction against the sepsis infection of MDR A. baumannii. It seems that in the future, these proteins can be considered as promising components in the development of the A. baumannii vaccine.

The Role of Combining Probiotics in Preventing and Controlling Inflammation: A Focus on the Anti-Inflammatory and Immunomodulatory Effects of Probiotics in an In Vitro Model of IBD.

Objective: IBD is an inflammatory disease with abnormalities such as dysbiosis and abnormal immune system activity. Probiotics, as live beneficial microorganisms, play a role in maintaining health through various mechanisms, including the modulation of the immune system and the control of inflammation. Here, we aimed to investigate the efficacy of a probiotic mixture of Lactobacillus spp. and Bifidobacterium spp. in modulating JAK/STAT and NF-kB inflammatory signaling pathways. Method: A quantitative real-time polymerase chain reaction (qPCR) assay was conducted to analyze the expression of JAK/STAT and inflammatory genes after treatment with the probiotic mixture before, after, and simultaneously with the sonicated pathogen in the HT-29 cell line. The production of IL-6 and IL-1ß after probiotic treatment was investigated via cytokine assay. Results: Treatment with probiotics resulted in downregulation of TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway and JAK/STAT genes compared with sonicat-treated cells as inflammation inducers. The production of IL-6 and IL-1 decreased after probiotic treatment. Conclusions: The probiotic mixture of Lactobacillus spp. and Bifidobacterium spp. showed anti-inflammatory effects by modulating JAK/STAT and NF-kB signaling pathways. The use of probiotics could be considered as an appropriate complementary treatment for patients with inflammatory bowel disease.

Dynamic Population of Gut Microbiota as an Indicator of Inflammatory Bowel Disease

Background: Inflammatory bowel disease is a chronic inflammatory disease of the gastrointestinal tract. The gut microbiota is an important factor in the pathogenesis of inflammatory bowel disease (IBD). Due to a link between the gut microbiota and IBD, studying microbiota changes using an accurate, sensitive and rapid method for detection of the disease seems necessary. This study aimed to compare the composition of gut microbiota in three groups of people, including IBD patients, cured Inflammatory bowel disease (CIBD), and healthy groups. Methods: For this study, 45 stool samples (15 from each group) were collected. Using real-time PCR, the abundance of 11 bacterial 16S rRNA gene sequences was examined. Results: In the IBD group, the number of three bacterial phyla, including Firmicutes, Actinobacteria, and Bacteroidetes, decreased (p < 0.01, p < 0.01, and p < 0.001, respectively), while the population of γ-Proteobacteria increased significantly (p < 0.0001). In the CIBD group, the number of Actinobacteria enhanced (p < 0.01), but that of Bacteroidetes and Firmicutes decreased (p < 0.01, and p < 0.05, respectively). Conclusion: Findings of this study indicate that decrease in Firmicutes and increase in γ-Proteobacteria could be used as an indicator of IBD instead of employing invasive and costly detection methods such as colonoscopy and other tests.

In Silico Analyses of Extracellular Proteins of Acinetobacter baumannii as Immunogenic Candidates.

Background: Acinetobacter baumannii is an important nosocomial pathogen causing high morbidity and mortality in immunocompromised patients with prolonged hospitalization. Multidrug-resistant A. baumannii infections are on the rise worldwide. Therefore, the discovery of an effective vaccine against this bacterium seems necessary as a cost-effective and preventive strategy. Methods: In this present study, 35 genomes of A. baumannii strains were considered, and the extracellular proteins were selected, maximally having one transmembrane helix with high adhesion probability and no similarity to host proteins, as immunogenic candidates using the web tool Vaxign. Subsequently, the role of these selected proteins in bacterial pathogenesis was investigated using VICMpred. Then, the major histocompatibility complex class II, linear B-cell epitopes, and conservation of epitopes were identified using the Immune Epitope Database, BepiPred, and Epitope Conservancy Analysis, respectively. Finally, the B-cell discontinuous epitopes of each protein were predicted using ElliPro and plotted on the three-dimensional structure (3D) of the proteins. The role of the unknown proteins was predicted using the STRING database. Results: In this study, eight acceptable immunogenic candidates, including FilF, FimA, putative acid phosphatase, putative exported protein, subtilisin-like serine protease, and three uncharacterized proteins, were identified in A. baumannii. Conclusions: The results of the STRING database showed that these three uncharacterized proteins play a role in nutrition (heme utilization), peptide bond cleavage (serine peptidases), and cellular processes (MlaD protein). Extracellular proteins might play a catalyst role in the outer membrane protein-based vaccine of A. baumannii. Furthermore, this study proposed a list of potent immunogenic candidates of extracellular proteins.

Anti-inflammatory and immunomodulatory effects of Lactobacillus spp. as a preservative and therapeutic agent for IBD control.

BACKGROUND: Probiotics have a beneficial effect on inflammatory responses and immune regulation, via Janus kinase/signal transduction and activator of transcription (JAK/STAT) and NF-κB signaling pathways. To evaluate the precise effects of Lactobacillus spp. as a protective and therapeutic agent, we aimed to investigate the efficacy of Lactobacillus spp. in modulating JAK/STAT and nuclear factor kappa B (NF-κB) inflammatory signaling pathways. METHODS: A quantitative real-time polymerase chain reaction (qPCR) assay was used to analyze the expression of JAK/STAT and inflammatory genes (TIR-associated Protein [TIRAP], Interleukin 1 Receptor Associated Kinase[IRAK4], Nuclear factor-kappa B Essential Modulator [NEMO], and receptor interacting protein [RIP]) followed by treatment of the HT-29 cell line with sonicated pathogens before, after, and simultaneously with Lactobacillus spp. A cytokine assay was also used to evaluate interleukin (IL)-6 and IL-1ß production after treatment with Lactobacillus spp. RESULTS: Lactobacillus spp. downregulated JAK and TIRAP, IRAK4, NEMO, and RIP genes in the NF-κB pathway compared to sonicate-treated cells. The expression of STAT genes was different after treatment with probiotics. The production of IL-6 and IL-1ß decreased after probiotic treatment. CONCLUSIONS: Our Lactobacillus spp. cocktail showed anti-inflammatory effects on HT-29 cells by modulating JAK/STAT and NF-κB signaling pathways in all three treatment variants. Therefore, Lactobacillus spp. as a dietary supplement can both prevent and reduce inflammation-related diseases such as inflammatory bowel disease.

The effects of the probiotic cocktail on modulation of the NF-kB and JAK/STAT signaling pathways involved in the inflammatory response in bowel disease model.

BACKGROUND: Probiotics positively affect inflammatory responses, in part, through Janus kinase/signal transduction and activator of transcription (JAK/STAT) and inflammatory signaling pathways. To evaluate the precise effects of probiotics as protective treatment, we aimed to investigate the effectiveness of Lactobacillus spp., Bifidobacterium spp., and a mixture of these probiotics in modulating the JAK/STAT and inflammatory signaling pathways. METHODS: A quantitative real-time polymerase chain reaction (qPCR) assay was used to analyze the expression of JAK/STAT and inflammatory genes (TIRAP, IRAK4, NEMO, and RIP) following HT-29 cell line treatment with sonicated pathogens Lactobacillus spp., Bifidobacterium spp., and a mixed cocktail. A cytokine assay was also used to evaluate the IL-6 and IL-1ß production following the probiotic treatment. RESULTS: The probiotic cocktail downregulated the JAK genes and TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway compared to sonicate pathogen treatment cells. The expression of STAT genes was variable following probiotic treatment. The IL-6 and IL-1ß production decreased after probiotic treatment. CONCLUSIONS: Our probiotic cocktail showed anti-inflammatory effects on HT-29 cells by modulating JAK/STAT and NF-kB pathways. Therefore, Lactobacillus spp. and Bifidobacterium spp. probiotics as nutritional supplements may reduce inflammation-associated diseases such as inflammatory bowel disease (IBD).

Molecular epidemiology of hypervirulent Klebsiella pneumoniae: a systematic review and meta-analysis.

Classical (CKp) and hypervirulent (hvKp) Klebsiella pneumoniae are two different circulating pathotypes. The aim of this study was to assess the prevalence, epidemiology and molecular relatedness of hvKps using a systemic review and meta-analysis. The data extracted from Medline, Embase, and Web of Science and finally 14 studies met the eligible criteria. To combine prevalence proportions of all studies, we performed the metaprop command embedded in the Meta package software. Totally, of 1814 K. pneumoniae isolates, 21.7% (394/1814) were hvKp. The molecular typing showed that all hvKp isolates were grouped into 50 different sequence types (STs) of them ST23, ST11, ST65 and ST86 were common. K1, K2 and K64 were dominant capsule serotypes that strongly related to ST23, ST65 and ST11, respectively. It seems that clonal group 23 (CG23) is associated with liver abscess and CG11 related to various clinical sources.