Dataset Information

Kuppfer cells trigger nonalcoholic steatohepatitis development in diet-induced mouse model through tumor necrosis factor-? production.

ABSTRACT:

Background

The mechanisms triggering nonalcoholic steatohepatitis (NASH) remain poorly defined.

Results

Kupffer cells are the first responding cells to hepatocyte injuries, leading to TNF? production, chemokine induction, and monocyte recruitment. The silencing of TNF? in myeloid cells reduces NASH progression.

Conclusion

Increase of TNF?-producing Kupffer cells is crucial for triggering NASH via monocyte recruitment.

Significance

Myeloid cells-targeted silencing of TNF? might be a tenable therapeutic approach. Nonalcoholic steatohepatitis (NASH), characterized by lipid deposits within hepatocytes (steatosis), is associated with hepatic injury and inflammation and leads to the development of fibrosis, cirrhosis, and hepatocarcinoma. However, the pathogenic mechanism of NASH is not well understood. To determine the role of distinct innate myeloid subsets in the development of NASH, we examined the contribution of liver resident macrophages (i.e. Kupffer cells) and blood-derived monocytes in triggering liver inflammation and hepatic damage. Employing a murine model of NASH, we discovered a previously unappreciated role for TNF? and Kupffer cells in the initiation and progression of NASH. Sequential depletion of Kupffer cells reduced the incidence of liver injury, steatosis, and proinflammatory monocyte infiltration. Furthermore, our data show a differential contribution of Kupffer cells and blood monocytes during the development of NASH; Kupffer cells increased their production of TNF?, followed by infiltration of CD11b(int)Ly6C(hi) monocytes, 2 and 10 days, respectively, after starting the methionine/choline-deficient (MCD) diet. Importantly, targeted knockdown of TNF? expression in myeloid cells decreased the incidence of NASH development by decreasing steatosis, liver damage, monocyte infiltration, and the production of inflammatory chemokines. Our findings suggest that the increase of TNF?-producing Kupffer cells in the liver is crucial for the early phase of NASH development by promoting blood monocyte infiltration through the production of IP-10 and MCP-1.

SUBMITTER: Tosello-Trampont AC

PROVIDER: S-EPMC3504730 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Publications

Kuppfer cells trigger nonalcoholic steatohepatitis development in diet-induced mouse model through tumor necrosis factor-α production.

Tosello-Trampont Annie-Carole AC Landes Susan G SG Nguyen Virginia V Novobrantseva Tatiana I TI Hahn Young S YS

The Journal of biological chemistry 20121012 48

<h4>Background</h4>The mechanisms triggering nonalcoholic steatohepatitis (NASH) remain poorly defined.<h4>Results</h4>Kupffer cells are the first responding cells to hepatocyte injuries, leading to TNFα production, chemokine induction, and monocyte recruitment. The silencing of TNFα in myeloid cells reduces NASH progression.<h4>Conclusion</h4>Increase of TNFα-producing Kupffer cells is crucial for triggering NASH via monocyte recruitment.<h4>Significance</h4>Myeloid cells-targeted silencing of ...[more]

PMID: 23066023

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