Inhibition of Bruton's TK regulates macrophage NF-?B and NLRP3 inflammasome activation in metabolic inflammation.

ABSTRACT: BACKGROUND AND PURPOSE:There are no medications currently available to treat metabolic inflammation. Bruton's tyrosine kinase (BTK) is highly expressed in monocytes and macrophages and regulates NF-?B and NLRP3 inflammasome activity; both propagate metabolic inflammation in diet-induced obesity. EXPERIMENTAL APPROACH:Using an in vivo model of chronic inflammation, high-fat diet (HFD) feeding, in male C57BL/6J mice and in vitro assays in primary murine and human macrophages, we investigated if ibrutinib, an FDA approved BTK inhibitor, may represent a novel anti-inflammatory medication to treat metabolic inflammation. KEY RESULTS:HFD-feeding was associated with increased BTK expression and activation, which was significantly correlated with monocyte/macrophage accumulation in the liver, adipose tissue, and kidney. Ibrutinib treatment to HFD-fed mice inhibited the activation of BTK and reduced monocyte/macrophage recruitment to the liver, adipose tissue, and kidney. Ibrutinib treatment to HFD-fed mice decreased the activation of NF-?B and the NLRP3 inflammasome. As a result, ibrutinib treated mice fed HFD had improved glycaemic control through restored signalling by the IRS-1/Akt/GSK-3? pathway, protecting mice against the development of hepatosteatosis and proteinuria. We show that BTK regulates NF-?B and the NLRP3 inflammasome specifically in primary murine and human macrophages, the in vivo cellular target of ibrutinib. CONCLUSION AND IMPLICATIONS:We provide "proof of concept" evidence that BTK is a novel therapeutic target for the treatment of diet-induced metabolic inflammation and ibrutinib may be a candidate for drug repurposing as an anti-inflammatory agent for the treatment of metabolic inflammation in T2D and microvascular disease.

SUBMITTER: Purvis GSD 

PROVIDER: S-EPMC7484557 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature