title: Resistin in dairy cows: plasma concentrations during early lactation, expression and potential role in adipose tissue.
abstract: Resistin is an adipokine that has been implicated in energy metabolism regulation in rodents but has been little studied in dairy cows. We determined plasma resistin concentrations in early lactation in dairy cows and investigated the levels of resistin mRNA and protein in adipose tissue and the phosphorylation of several components of insulin signaling pathways one week post partum (1 WPP) and at five months of gestation (5 MG). We detected resistin in mature bovine adipocytes and investigated the effect of recombinant bovine resistin on lipolysis in bovine adipose tissue explants. ELISA showed that plasma resistin concentration was low before calving, subsequently increasing and reaching a peak at 1 WPP, decreasing steadily thereafter to reach pre-calving levels at 6 WPP. Plasma resistin concentration was significantly positively correlated with plasma non esterified fatty acid (NEFA) levels and negatively with milk yield, dry matter intake and energy balance between WPP1 to WPP22. We showed, by quantitative RT-PCR and western blotting, that resistin mRNA and protein levels in adipose tissue were higher at WPP1 than at 5 MG. The level of phosphorylation of several early and downstream insulin signaling components (IRβ, IRS-1, IRS-2, Akt, MAPK ERK1/2, P70S6K and S6) in adipose tissue was also lower at 1 WPP than at 5 MG. Finally, we showed that recombinant bovine resistin increased the release of glycerol and mRNA levels for ATGL (adipose triglyceride lipase) and HSL (hormone-sensitive lipase) in adipose tissue explants. Overall, resistin levels were high in the plasma and adipose tissue and were positively correlated with NEFA levels after calving. Resistin is expressed in bovine mature adipocytes and promotes lipid mobilization in adipose explants in vitro.
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: Reverchon
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Ramé
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Juliette
authors.initials: J
authors.lastname: Cognié
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Briant
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Elis
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Guillaume
authors.affiliation: INRA, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR6175 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, Tours, France; Institut Français du Cheval, Nouzilly, France.
authors.forename: Joëlle
authors.initials: J
authors.lastname: Dupont
mesh_terms: D017667:Adipocytes / Q000378:metabolism; D052242:Adiponectin / Q000378:metabolism; D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D005260:Female; D015870:Gene Expression; D055504:Insulin Receptor Substrate Proteins / Q000378:metabolism; D007774:Lactation / Q000097:blood* / Q000235:genetics*; D008049:Lipase / Q000235:genetics / Q000378:metabolism; D020935:MAP Kinase Signaling System; D010766:Phosphorylation; D049590:Postpartum Period; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017526:Receptor, IGF Type 1 / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism; D052243:Resistin / Q000097:blood / Q000235:genetics* / Q000378:metabolism*; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism
chemical_list: D052242:Adiponectin; D055504:Insulin Receptor Substrate Proteins; D012333:RNA, Messenger; D052243:Resistin; D017526:Receptor, IGF Type 1; D011972:Receptor, Insulin; D051057:Proto-Oncogene Proteins c-akt; D019893:Ribosomal Protein S6 Kinases; D008049:Lipase