title: C-peptide modifies leptin and visfatin secretion in human adipose tissue.
abstract: OBJECTIVE
  The effects of C-peptide on adipose tissue, an organ involved in the development of obesity and insulin resistance, are not yet well known. The aim of this study was to determine whether C-peptide could be involved in the regulation of the adipocytokine synthesis in human visceral adipose tissue.
  
  
  METHODS
  The association between C-peptide and different serum adipocytokines, with an intravenous glucose tolerance test (IVGTT), and in an in vitro study in subjects without obesity and in subjects with morbid obesity were analyzed.
  
  
  RESULTS
  In different multiple regression analysis models, C-peptide and C-peptide increase above basal levels during total IVGTT and between 0 and 10 min were associated positively with leptin and negatively with visfatin. Rhodamine-labeled C-peptide binds to human adipocytes, and this binding was blocked with excess of unlabeled C-peptide. Exposure of human visceral explants and adipocytes from subjects with morbid obesity to C-peptide at 1 and 10 nM induced a significant increase in leptin and a decrease in visfatin secretion. In subjects without obesity, these C-peptide effects were found mainly at 10 nM. These effects can be inhibited by phosphatidylinositol 3-kinase (PI3K) or protein kinase B (PKB) inhibitors.
  
  
  CONCLUSIONS
  C-peptide may be involved in the regulation of leptin and visfatin secretion, molecules intimately involved in energy homeostasis processes, through PI3K or PKB pathways.
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER De Diabetes Y Enfermedades Metabólicas (CIBERDEM), Málaga, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Garcia-Serrano
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Carolina
authors.initials: C
authors.lastname: Gutiérrez-Repiso
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gonzalo
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Garcia-Arnes
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER De Diabetes Y Enfermedades Metabólicas (CIBERDEM), Málaga, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Valdes
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER De Diabetes Y Enfermedades Metabólicas (CIBERDEM), Málaga, Spain.|CIBER Fisiopatología De La Obesidad Y Nutrición (CIBEROBN), Málaga, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Soriguer
authors.affiliation: Unidad De Gestión Clínica De Laboratorio, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Vidal
authors.initials: V
authors.lastname: Perez-Valero
authors.affiliation: Unidad De Gestión Clínica De Laboratorio, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Alaminos-Castillo
authors.affiliation: Unidad De Gestión Clínica De Cirugía General, Digestiva Y Trasplantes, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Francisco Cobos-Bravo
authors.affiliation: Unidad De Gestión Clínica De Cirugía General, Digestiva Y Trasplantes, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Moreno-Ruiz
authors.affiliation: Unidad De Gestión Clínica De Cirugía General, Digestiva Y Trasplantes, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Rodriguez-Cañete
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER De Diabetes Y Enfermedades Metabólicas (CIBERDEM), Málaga, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Rodríguez-Pacheco
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER De Diabetes Y Enfermedades Metabólicas (CIBERDEM), Málaga, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Garcia-Escobar
authors.affiliation: Unidad De Gestión Clínica De Endocrinología Y Nutrición, Instituto De Investigacion Biomédica De Málaga (IBIMA), Hospital Regional Universitario, Málaga, Spain.|CIBER Fisiopatología De La Obesidad Y Nutrición (CIBEROBN), Málaga, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: García-Fuentes
mesh_terms: D054392:Adipokines / Q000737:chemistry*; D000273:Adipose Tissue / Q000187:drug effects*; D000328:Adult; D002096:C-Peptide / Q000097:blood* / Q000737:chemistry*; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D020738:Leptin / Q000097:blood* / Q000737:chemistry*; D008297:Male; D054409:Nicotinamide Phosphoribosyltransferase / Q000097:blood / Q000737:chemistry*; D019869:Phosphatidylinositol 3-Kinases
chemical_list: D054392:Adipokines; D002096:C-Peptide; D020738:Leptin; D054409:Nicotinamide Phosphoribosyltransferase; D019869:Phosphatidylinositol 3-Kinases