Dataset Information

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

ABSTRACT: Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1(-/-) mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS)-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF) expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis.

SUBMITTER: Seifert L

PROVIDER: S-EPMC4681001 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

Seifert Lena L Deutsch Michael M Alothman Sara S Alqunaibit Dalia D Werba Gregor G Pansari Mridul M Pergamo Matthew M Ochi Atsuo A Torres-Hernandez Alejandro A Levie Elliot E Tippens Daniel D Greco Stephanie H SH Tiwari Shaun S Ly Nancy Ngoc Giao NNG Eisenthal Andrew A van Heerden Eliza E Avanzi Antonina A Barilla Rocky R Zambirinis Constantinos P CP Rendon Mauricio M Daley Donnele D Pachter H Leon HL Hajdu Cristina C Miller George G

Cell reports 20151119 9

Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate ...[more]

PMID: 26655905

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Project description:BackgroundLiver fibrosis and fibrosis-related hepatocarcinogenesis are a rising cause for morbidity and death worldwide. Although transforming growth factor-β (TGF-β) is a critical mediator of chronic liver fibrosis, targeting TGF-β isoforms and receptors lead to unacceptable side effect. This study was designed to explore the antifibrotic effect of Compound kushen injection (CKI), an approved traditional Chinese medicine formula, via a therapeutic strategy of rebalancing TGF-β/Smad7 signaling.MethodsA meta-analysis was performed to evaluate CKI intervention on viral hepatitis-induced fibrosis or cirrhosis in clinical randomized controlled trials (RCTs). Mice were given carbon tetrachloride (CCl4 ) injection or methionine-choline deficient (MCD) diet to induce liver fibrosis, followed by CKI treatment. We examined the expression of TGF-β/Smad signaling and typical fibrosis-related genes in hepatic stellate cells (HSCs) and fibrotic liver tissues by qRT-PCR, Western blotting, RNA-seq, immunofluorescence, and immunohistochemistry.ResultsBased on meta-analysis results, CKI improved the liver function and relieved liver fibrosis among patients. In our preclinical studies by using two mouse models, CKI treatment demonstrated promising antifibrotic effects and postponed hepatocarcinogenesis with improved liver function and histopathologic features. Mechanistically, we found that CKI inhibited HSCs activation by stabilizing the interaction of Smad7/TGF-βR1 to rebalance Smad2/Smad3 signaling, and subsequently decreased the extracellular matrix formation. Importantly, Smad7 depletion abolished the antifibrotic effect of CKI in vivo and in vitro. Moreover, matrine, oxymatrine, sophocarpine, and oxysophocarpine were identified as material basis responsible for the antifibrosis effect of CKI.ConclusionsOur results unveil the approach of CKI in rebalancing TGF-β/Smad7 signaling in HSCs to protect against hepatic fibrosis and hepatocarcinogenesis in both preclinical and clinical studies. Our study suggests that CKI can be a candidate for treatment of hepatic fibrosis and related oncogenesis.

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Dataset Information

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

Publications

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

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