RIPK1 protects from TNF-α-mediated liver damage during hepatitis

Abstract : Cell death of hepatocytes is a prominent characteristic in the pathogenesis of liver disease, while hepatolysis is a starting point of inflammation in hepatitis and loss of hepatic function. However, the precise molecular mechanisms of hepatocyte cell death, the role of the cytokines of hepatic microenvironment and the involvement of intracellular kinases, remain unclear. Tumor necrosis factor alpha (TNF-α) is a key cytokine involved in cell death or survival pathways and the role of RIPK1 has been associated to the TNF-α-dependent signaling pathway. We took advantage of two different deficient mouse lines, the RIPK1 kinase dead knock-in mice (Ripk1K45A) and the conditional knockout mice lacking RIPK1 only in liver parenchymal cells (Ripk1LPC-KO), to characterize the role of RIPK1 and TNF-α in hepatitis induced by concanavalin A (ConA). Our results show that RIPK1 is dispensable for liver homeostasis under steady-state conditions but in contrast, RIPK1 kinase activity contributes to caspase-independent cell death induction following ConA injection and RIPK1 also serves as a scaffold, protecting hepatocytes from massive apoptotic cell death in this model. In the Ripk1LPC-KO mice challenged with ConA, TNF-α triggers apoptosis, responsible for the observed severe hepatitis. Mechanism potentially involves both TNF-independent canonical NF-κB activation, as well as TNF-dependent, but canonical NF-κB-independent mechanisms. In conclusion, our results suggest that RIPK1 kinase activity is a pertinent therapeutic target to protect liver against excessive cell death in liver diseases. © The Author(s) 2016.
Complete list of metadatas

Cited literature [28 references]  Display  Hide  Download

https://hal-univ-rennes1.archives-ouvertes.fr/hal-01414916
Contributor : Laurent Jonchère <>
Submitted on : Monday, November 19, 2018 - 3:39:58 PM
Last modification on : Thursday, July 11, 2019 - 1:00:55 AM

File

cddis2016362a.pdf
Publisher files allowed on an open archive

Identifiers

Citation

A. Filliol, C. Piquet-Pellorce, J. Le Seyec, M. Farooq, V. Genet, et al.. RIPK1 protects from TNF-α-mediated liver damage during hepatitis. Cell Death and Disease , Nature Publishing Group, 2016, 7, pp.e2462. ⟨10.1038/cddis.2016.362⟩. ⟨hal-01414916⟩

Share

Metrics

Record views

135

Files downloads

70