Peroxynitrite activates glucose uptake in 3T3-L1 adipocytes through a PI3-K-dependent mechanism.

نویسندگان

  • Alberto M Guzman-Grenfell
  • Rebeca Garcia-Macedo
  • Marco T Gonzalez-Martinez
  • Juan Jose Hicks
  • Rafael Medina-Navarro
چکیده

Peroxynitrite, the product of the reaction between *NO and O2*-, is a strong oxidant and nitrating molecule, and it has been recently consideredas a component of some important signaling pathways. Herein, we report the effect of peroxynitrite on glucose uptake in 3T3-L1 adipocytes. Peroxynitrite stimulated glucose uptake and this effect was inhibited by citochalasin B, indicating the participation of facilitated GLUT transporters. Peroxynitrite-induced glucose uptake was not related to intracellular ATP, nor to external or internal calcium, but it was inhibited by the phosphatidylinositol 3-kinase (PI3-K) inhibitor, wortmannin. Additionally, we also found that peroxynitrite did not activate the insulin receptor nor the PI3-K downstream signaling protein kinase B (PKB/Akt). The dose-dependent inhibitory action of wortmannin suggests that peroxynitrite activates glucose transport without affecting GLUT transporters translocation.

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عنوان ژورنال:
  • Frontiers in bioscience : a journal and virtual library

دوره 10  شماره 

صفحات  -

تاریخ انتشار 2005