Activated Ask1-MKK4-p38MAPK/JNK stress signaling pathway in human omental fat tissue may link macrophage infiltration to whole-body Insulin sensitivity. Academic Article uri icon

abstract

  • Context: Adipose tissue in obesity is thought to be exposed to various stresses, predominantly in intraabdominal depots. We recently reported that p38MAPK and Jun N-terminal kinase (JNK), but not ERK and inhibitory-κB kinase β, are more highly expressed and activated in human omental (OM) adipose tissue in obesity. Objective: The aim was to investigate upstream components of the pathways that culminate in activation of p38MAPK and JNK. Setting and Patients: Phosphorylation and expression of kinases were studied in paired samples of OM and sc adipose tissue from lean and obese subjects of two different cohorts (n = 36 and n = 196) by Western and real-time PCR analyses. The association with fat distribution, macrophage infiltration, insulin sensitivity, and glucose metabolism was assessed by correlation analyses. Results: The amount of phosphorylated forms of the kinases provided evidence for an activated stress-sensing pathway consisting of the MAP3K Ask1 (but not MLK3 or Tak1), and the MAP2Ks MKK4, 3/6, (...

publication date

  • April 1, 2009