title: IL-13 improves beta-cell survival and protects against IL-1beta-induced beta-cell death.
abstract: OBJECTIVE
  IL-13 is a cytokine classically produced by anti-inflammatory T-helper-2 lymphocytes; it is decreased in the circulation of type 2 diabetic patients and impacts positively on liver and skeletal muscle. Although IL-13 can exert positive effects on beta-cell lines, its impact and mode of action on primary beta-cell function and survival remain largely unexplored.
  
  
  METHODS
  Beta-cells were cultured for 48 h in the presence of IL-13 alone or in combination with IL-1β or cytokine cocktail (IL-1β, IFNγ, TNFα).
  
  
  RESULTS
  IL-13 protected human and rat beta-cells against cytokine induced death. However, IL-13 was unable to protect from IL-1β impaired glucose stimulated insulin secretion and did not influence NFκB nuclear relocalization induced by IL-1β. IL-13 induced phosphorylation of Akt, increased IRS2 protein expression and counteracted the IL-1β induced regulation of several beta-cell stress response genes.
  
  
  CONCLUSIONS
  The prosurvival effects of IL-13 thus appear to be mediated through IRS2/Akt signaling with NFκB independent regulation of gene expression. In addition to previously documented beneficial effects on insulin target tissues, these data suggest that IL-13 may be useful for treatment of type 2 diabetes by preserving beta-cell mass or slowing its rate of decline.
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland. Electronic address: Sabine.RuttiRoch@unil.ch.
authors.forename: Sabine
authors.initials: S
authors.lastname: Rütti
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland.
authors.forename: Cédric
authors.initials: C
authors.lastname: Howald
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Arous
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland.
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Dermitzakis
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland.
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Halban
authors.affiliation: Department of Genetic Medicine and Development, University of Geneva Medical Center, Geneva, Switzerland.
authors.forename: Karim
authors.initials: K
authors.lastname: Bouzakri
keywords: Akt; Apoptosis; Beta-cells; Cytokines; Gene expression