Exposure to TNF-alpha but not IL-1beta impairs insulin-dependent phosphorylation of protein kinase B and p70S6k in mouse C2C12 myogenic cells.

Abstract

i) high concentrations of TNF-alpha, but not IL-beta, present in the extracellular environment during myoblast differentiation prevent the stimulatory action of insulin on glucose uptake and protein synthesis; ii) insulin resistance induced by TNF-alpha in C2C12 myogenic cells could be associated with the decreased insulin-mediated phosphorylation of PKB and p70s6k, but not with the basal phosphorylation of p42MAPK.