Summary
Hepatocyte replication maintains liver homeostasis and integrity. It is impaired in chronic liver disease, promoting disease progression. Herein, we have identified NF-kB-inducing kinase (NIK) as an unrecognized suppressor of hepatocyte replication. Hepatic NIK was aberrantly activated in chronic liver disease. Hepatocyte-specific deletion of NIK or its downstream mediator IKKα substantially accelerated hepatocyte proliferation and liver regeneration following partial hepatectomy. Mechanistically, NIK and IKKα suppressed the mitogenic JAK2/STAT3 pathway, thereby inhibiting hepatocyte cell cycle progression. Remarkably, inactivation of hepatic NIK largely reversed suppression of the hepatic JAK2/STAT3 pathway, hepatocyte replication, and liver regeneration induced by either chronic liver injury or metabolic stress. Our data suggest that hepatic NIK acts as a rheostat for liver regeneration to restrain liver overgrowth. Pathologic activation of hepatic NIK blocks hepatocyte replication, likely contributing to liver disease progression.
- Abbreviations
- PHx
- hepatectomy;
- HFD
- high fat diet;
- NIK
- NF-κB-inducing Kinase;
- JAK2
- Janus kinase 2;
- STAT3
- Signal transducer and activator of transcription 3;
- AAF
- 2-acetylaminofluorence.
Footnotes
Disclosure statement: All authors have nothing to declare.