Title

Bone marrow-derived c-jun N-terminal kinase-1 (JNK1) mediates liver regeneration

UMMS Affiliation

Program in Molecular Medicine

Date

1-1-2015

Document Type

Article

Medical Subject Headings

Animals; Bone Marrow; Liver Regeneration; Mice; Mice, Inbred C57BL; Mice, Knockout; Mitogen-Activated Protein Kinase 8; Real-Time Polymerase Chain Reaction

Disciplines

Biochemistry | Cell Biology | Cellular and Molecular Physiology | Molecular Biology

Abstract

Liver regeneration is controlled by a complex network of signaling molecules, and a prominent role for c-jun N-terminal kinase has been suggested during this process. In the present study, we aimed to characterize and define the cell-type-specific contribution of JNK1 activation during liver regeneration. We used hepatocyte-specific JNK1 knockout mice (JNK1(Deltahepa)) using the cre/lox-P system. We performed partial hepatectomy (PH) in WT, JNK1(Deltahepa) and JNK1(-/-) animals and investigated time-points up to 72 h after PH. Additionally, bone marrow transplantation experiments were conducted in order to identify the contribution of hematopoietic cell-derived JNK1 activation for liver regeneration. Our results show that liver regeneration was significantly impaired in JNK1(-/-) compared to JNK1(Deltahepa) and WT animals. These data were evidenced by lower BrdU incorporation and decreased cell cycle markers such as Cyclin A, Cyclin D, E2F1 and PCNA 48 h after PH in JNK1(-/-) compared with JNK1(Deltahepa) and WT livers. In JNK1(-/-) mice, our findings were associated with a reduced acute phase response as evidenced by a lower activation of the IL-6/STAT3/SAA-1 cascade. Additionally, CD11b(+)Ly6G(+)-cells were decreased in JNK1(-/-) compared with JNK1(Deltahepa) and WT animals after PH. The transplantation of bone marrow-derived JNK1(-/-) into WT recipients caused significant reduction in liver regeneration. Interestingly, the transplantation of JNK1(-/-) into mice lacking JNK1 in hepatocytes only partially delayed liver regeneration. In summary, we provide evidence that (1) JNK1 in hematopoietic cells is crucial for liver regeneration, and (2) a synergistic function between JNK1 in hepatocytes and hematopoietic-derived cells is involved in the hepatic regenerative response.

Rights and Permissions

Citation: Biochim Biophys Acta. 2015 Jan;1852(1):137-45. doi: 10.1016/j.bbadis.2014.10.011. Epub 2014 Oct 22. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Keywords

Hepatocyte, Immune cells, JNK1, Partial hepatectomy, STAT3

PubMed ID

25445542