The protein tyrosine kinase SYK regulates the alternative p38 activation in liver during acute liver inflammation

Sci Rep. 2019 Nov 28;9(1):17838. doi: 10.1038/s41598-019-54335-3.

Abstract

Two distinct p38 signaling pathways, classical and alternative, have been identified to regulate inflammatory responses in host defense and disease development. The role of alternative p38 activation in liver inflammation is elusive, while classical p38 signaling in hepatocytes plays a role in regulating the induction of cell death in autoimmune-mediated acute liver injury. In this study, we found that a mutation of alternative p38 in mice augmented the severity of acute liver inflammation. Moreover, TNF-induced hepatocyte death was augmented by a mutation of alternative p38, suggesting that alternative p38 signaling in hepatocytes contributed more significantly to the pathology of acute liver injury. Furthermore, SYK-Vav-1 signaling regulates alternative p38 activation and the downregulation of cell death in hepatocytes. Therefore, it is suggested that alternative p38 signaling in the liver plays a critical role in the induction and subsequent pathological changes of acute liver injury. Collectively, our results imply that p38 signaling in hepatocytes plays a crucial role to prevent excessive liver injury by regulating the induction of cell death and inflammation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Death
  • Cells, Cultured
  • Cytokines / genetics
  • Cytokines / metabolism
  • Female
  • Hepatitis, Animal / metabolism*
  • Hepatocytes / metabolism
  • MAP Kinase Signaling System*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mutation
  • Proto-Oncogene Proteins c-vav / genetics
  • Proto-Oncogene Proteins c-vav / metabolism
  • Syk Kinase / genetics
  • Syk Kinase / metabolism*
  • p38 Mitogen-Activated Protein Kinases / genetics
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Cytokines
  • Proto-Oncogene Proteins c-vav
  • Vav1 protein, mouse
  • Syk Kinase
  • p38 Mitogen-Activated Protein Kinases