JAK2 inhibition prevents innate immune responses and rescues animals from sepsis.

Abstract

Sepsis, a leading cause of death in hospitalized patients, is characterized by lethal systemic inflammatory responses. JAK2 is an essential tyrosine kinase modulating immune responses. However, the implications of JAK2 in infectious disorders remain undetermined. Here, we report that JAK2 inhibitors rescue animals from polymicrobial sepsis in a clinically relevant time frame. JAK2 inhibition with AG490 prevents NF-kappaB activation, modulates macrophage activation, and restrains the production of inflammatory cytokines. The inhibition of JAK2 blunted TNF production in both macrophages and splenocytes in a concentration-dependent manner. JAK2 inhibition specifically prevents LPS-induced STAT3 tyrosine phosphorylation without affecting serine phosphorylation in macrophages. JAK2 inhibitor prevents the activation of the canonical p65RelA/p50NF-kappaB1 pathway but not the other NF-kappaB proteins. In vivo, JAK2 inhibition restrains serum TNF levels by modulating TNF production in the lung and the spleen and protects mice from lethal endotoxemia in a concentration-dependent manner. AG490 also inhibits extracellular release of HMGB1 from macrophages and prevents an increase in serum HMGB1 levels during sepsis. JAK2 inhibition started at 24 h after the onset of sepsis rescued the mice from polymicrobial sepsis. Our study is the first experimental evidence that JAK2 inhibitors may provide a pharmacological advantage for the treatment of sepsis in a clinically relevant time frame.

• Authors: Geber Peña, Bolin Cai, Edwin A Deitch, Luis Ulloa
• Journal: Journal of molecular medicine (Berlin, Germany) (J Mol Med (Berl)) Vol. 88 Issue 8 Pg. 851-9 (Aug 2010) ISSN: 1432-1440 [Electronic] Germany
• PMID: 20393690 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Cytokines
• Enzyme Inhibitors
• HMGB1 Protein
• NF-kappa B
• STAT3 Transcription Factor
• Tumor Necrosis Factor-alpha
• Tyrphostins
• alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide
• Janus Kinase 2

Topics

• Animals
• Cell Line
• Cytokines (immunology)
• Enzyme Inhibitors (therapeutic use)
• HMGB1 Protein (blood)
• Humans
• Immunity, Innate (drug effects)
• Janus Kinase 2 (antagonists & inhibitors, immunology)
• Macrophages (immunology)
• Male
• Mice
• Mice, Inbred C57BL
• NF-kappa B (immunology)
• STAT3 Transcription Factor (immunology)
• Sepsis (drug therapy)
• Tumor Necrosis Factor-alpha (immunology)
• Tyrphostins (therapeutic use)