title: Oleic acid induces intracellular calcium mobilization, MAPK phosphorylation, superoxide production and granule release in bovine neutrophils.
abstract: Oleic acid (OA) is a nonesterified fatty acid that is released into the blood during lipomobilization at the time of calving in cows, a period where increased risk of infection and acute inflammation is observed. These data suggest potential OA-mediated regulation of innate immune responses. In the present study, we assessed the effects of OA on intracellular calcium release, ERK1/2 phosphorylation, superoxide production, CD11b expression and matrix metalloproteinase-9 (MMP-9) release in bovine neutrophils. Furthermore, the presence of GPR40, an OA receptor, was assessed by RT-PCR, immunoblotting and confocal microscopy. OA induced, in a dose-dependent manner, intracellular calcium mobilization, superoxide production and CD11b expression in bovine neutrophils; these effects were reduced by the intracellular chelating agent BAPTA-AM. OA also induced ERK2 phosphorylation and MMP-9 release. RT-PCR analysis detected mRNA expression of a bovine ortholog of the GPR40 receptor. Using a polyclonal antibody against human GPR40, we detected a protein of 31kDa by immunoblotting that was localized predominately in the plasma membrane. The selective agonist of GPR40, GW9508, induced intracellular calcium mobilization and ERK2 phosphorylation. In conclusion, OA can modulate bovine neutrophil responses in an intracellular calcium-dependent manner; furthermore, these responses could be induced by GPR40 activation.
authors.affiliation: Laboratory of Molecular Pharmacology, Institute of Pharmacology, Universidad Austral de Chile, Valdivia, Chile. mahidalgo@uach.cl
authors.forename: Maria A
authors.initials: MA
authors.lastname: Hidalgo
authors.forename: Carla
authors.initials: C
authors.lastname: Nahuelpan
authors.forename: Carolina
authors.initials: C
authors.lastname: Manosalva
authors.forename: Evelyn
authors.initials: E
authors.lastname: Jara
authors.forename: Maria D
authors.initials: MD
authors.lastname: Carretta
authors.forename: Ivan
authors.initials: I
authors.lastname: Conejeros
authors.forename: Anitsi
authors.initials: A
authors.lastname: Loaiza
authors.forename: Ricardo
authors.initials: R
authors.lastname: Chihuailaf
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Burgos
mesh_terms: D000818:Animals; D018949:Antigens, CD1 / Q000235:genetics / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D008744:Methylamines / Q000494:pharmacology; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D019301:Oleic Acid / Q000378:metabolism / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D011422:Propionates / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*
chemical_list: D018949:Antigens, CD1; C515630:GW9508; D008744:Methylamines; D011422:Propionates; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; D013481:Superoxides; D019301:Oleic Acid; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020780:Matrix Metalloproteinase 9; D002118:Calcium