title: Lactobacillus reuteri CRL1098 soluble factors modulate tumor necrosis factor alpha production in peripheral blood mononuclear cells: involvement of lipid rafts.
abstract: The aim of the present study was to evaluate the capacity of Lactobacillus reuteri CRL1098 soluble factors (Lr-S) to modulate TNF-α production in peripheral blood mononuclear cells (PBMC) and to study lipid rafts participation in this response. PBMC treated with Lr-S showed a reduced production of TNF-α. In addition, Lr-S treatment activated ERK and p38 MAPK pathways in PBMC. Lipid rafts participation in the reduced production of TNF-α by PBMC induced by Lr-S was verified by lipid rafts disruption with methyl-β-cyclodextrin and the reduction of the Src-tyrosine kinase Lck localization in rafts. Moreover, PBMC pre-treatment with Lck inhibitors blocked the effect of Lr-S on TNF-α production suggesting that activation and mobilization of Lck from lipid rafts would be involved in the modulatory effect of L. reuteri CRL1098. A secreted peptide of 5785 Da would be responsible of the modulatory effect of CRL1098 strain. This study demonstrated for the first time the lipid rafts participation in a response induced by a beneficial bacterium. Also, these results open new possibilities for investigating the molecular mechanisms involved in the interaction of probiotic bacterial extracellular compounds with immune cells.
authors.affiliation: Centro de Referencia para Lactobacilos, CERELA-CONICET, Chacabuco 145, T4000ILC Tucumán, Argentina. mmechoud@cerela.org.ar
authors.forename: Mónica A
authors.initials: MA
authors.lastname: Mechoud
authors.forename: Melina V
authors.initials: MV
authors.lastname: Mateos
authors.forename: Graciela Font
authors.initials: GF
authors.lastname: de Valdez
authors.forename: Julio
authors.initials: J
authors.lastname: Villena
authors.forename: Gabriela A
authors.initials: GA
authors.lastname: Salvador
authors.forename: Ana V
authors.initials: AV
authors.lastname: Rodriguez
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D052200:Limosilactobacillus reuteri / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000166:cytology* / Q000502:physiology*; D021962:Membrane Microdomains; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*; D055815:Young Adult
chemical_list: D014409:Tumor Necrosis Factor-alpha; D011505:Protein-Tyrosine Kinases