title: The Glycogen Synthase Kinase 3α and β Isoforms Differentially Regulates Interleukin-12p40 Expression in Endothelial Cells Stimulated with Peptidoglycan from Staphylococcus aureus.
abstract: Glycogen synthase kinase 3 (GSK3) is a constitutively active regulatory enzyme that is important in cancer, diabetes, and cardiovascular, neurodegenerative, and psychiatric diseases. While GSK3α is usually important in neurodegenerative and psychiatric diseases GSK3β is fundamental in the inflammatory response caused by bacterial components. Peptidoglycan (PGN), one of the most abundant cell-wall structures of Gram-positive bacteria, is an important inducer of inflammation. To evaluate whether inhibition of GSK3α and GSK3β activity in bovine endothelial cells (BEC) regulates the expression of the pro-inflammatory cytokine IL-12p40, we treated BEC with SDS-purified PGN from Staphylococcus aureus. We found that PGN triggered a TLR2/PI3K/Akt-dependent phosphorylation of GSK3α at Ser21, GSK3β at Ser9, and NF-κB p65 subunit (p65) at Ser536, and the phosphorylation of GSK3α was consistently higher than that of GSK3β. The expression of IL-12p40 was inhibited in BEC stimulated with PGN and pre-treated with a specific neutralizing anti-TLR2 antibody that targets the extracellular domain of TLR2 or by the addition of Akt-i IV (an Akt inhibitor). Inhibition of GSK3α and GSK3β with LiCl or SB216763 induced an increase in IL-12p40 mRNA and protein. The effect of each isoform on IL-12p40 expression was evaluated by siRNA-gene expression silencing of GSK3α and GSK3β. GSK3α gene silencing resulted in a marked increase in IL-12p40 mRNA and protein while GSK3β gene silencing had the opposite effect on IL-12p40 expression. These results indicate that the TLR2/PI3K/Akt-dependent inhibition of GSK3α activity also plays an important role in the inflammatory response caused by stimulation of BEC with PGN from S. aureus.
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Ricarda
authors.initials: R
authors.lastname: Cortés-Vieyra
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Octavio
authors.initials: O
authors.lastname: Silva-García
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Javier
authors.initials: J
authors.lastname: Oviedo-Boyso
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Huante-Mendoza
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Bravo-Patiño
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Valdez-Alarcón
authors.affiliation: Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: B Brett
authors.initials: BB
authors.lastname: Finlay
authors.affiliation: Molecular Immunology and Signal Transduction Laboratory, Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Carretera Morelia-Zinapécuaro, La Palma, Tarímbaro, Morelia, Michoacán, México.
authors.forename: Víctor M
authors.initials: VM
authors.lastname: Baizabal-Aguirre
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D003470:Culture Media / Q000737:chemistry / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D038362:Glycogen Synthase Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D007211:Indoles / Q000494:pharmacology; D053762:Interleukin-12 Subunit p40 / Q000235:genetics / Q000378:metabolism*; D018021:Lithium Chloride / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D010457:Peptidoglycan / Q000276:immunology / Q000494:pharmacology*; D010766:Phosphorylation; D015398:Signal Transduction / Q000187:drug effects; D013211:Staphylococcus aureus / Q000276:immunology / Q000378:metabolism*
chemical_list: D003470:Culture Media; D007211:Indoles; D053762:Interleukin-12 Subunit p40; D008301:Maleimides; D010457:Peptidoglycan; C417521:SB 216763; D000071679:Glycogen Synthase Kinase 3 beta; D038362:Glycogen Synthase Kinase 3; C448021:glycogen synthase kinase 3 alpha; D018021:Lithium Chloride