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The LKB1/AMPK pathway is a central mediator of the hepatic xenobiotic response

ABSTRACT: The serine/threonine kinase LKB1 is a tumor suppressor gene which also plays key roles in metabolic function in peripheral tissues through its direct phosphorylation and activation of the AMP-activated protein kinase (AMPK). The LKB1/AMPK pathway plays key roles in the liver in suppressing transcriptional programs of gluconeogenesis and lipogenesis, and hepatic LKB1 is required for the ability of the type 2 diabetes agent metformin to lower blood glucose levels in mice. To more broadly define how the LKB1/AMPK pathway controls hepatic metabolism, transcriptional profiling was employed using mice with an inducible liver-specific deletion of Lkb1. Unexpectedly, LKB1/AMPK signaling broadly controls the expression of many phase I xenobiotic metabolism genes, including several members of the cytochrome P450 family. In particular, expression of CYP2E1, an important mediator of drug detoxification, was markedly reduced upon LKB1 loss. LKB1 liver-specific knockout mice exposed to hepatocarcinogens, exhibited marked resistance to carcinogen-induced hepatocyte apoptosis, proliferation, senescence, and liver fibrosis and tumorigenesis.

ORGANISM(S): Mus musculus

PROVIDER: GSE21984 | GEO | 2019/05/01

REPOSITORIES: GEO

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Transcriptional profiling of Ampk-deficient B cells during terminal differentiation

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