The adenosine derivative 2′,3′,5′-tri-O-acetyl-N6-(3-hydroxylaniline) adenosine activates AMPK and regulates lipid metabolism in vitro and in vivo

Aims: Our overall objective was to investigate the effect of the adenosine derivative 2',3',5'-tri-O-acetyl-N6-(3-hydroxylaniline) adenosine (WS010117) on AMP-activated protein kinase (AMPK) activation and lipid metabolism and to also assess the underlying mechanisms involved in these processes. Main methods: HepG2 cells and hamsters fed a high-fat diet were used to test the effects of WS010117 on lipid metabolism. Western blots, chemical intervention, HPLC, SAMS peptide assay, (14)C-labelled acetate and palmitate assays, molecular docking assay and siRNA targeting the AMPK gamma 1 subunit were used to investigate the effect of WS010117 on AMPK activation as well as the underlying mechanism involved in this activation. Key findings: WS010117 treatment resulted in the dose-dependent activation of AMPK in HepG2 cells, increasing lipid oxidation and decreasing lipid biosynthesis. In hamsters that were fed a high-fat diet. WS010117 treatment (1.5-6 mg/kg) significantly inhibited the increase in lipid accumulation. WS010117-induced AMPK activation was essentially abolished by treatment with compound C, and the addition of WS010117 did not alter the intracellular AMP:ATP ratio. In HeLa cells endogenously lacking LKB1, WS010117-mediated AMPK activation was not impaired, even following co-treatment with STO-609, a selective inhibitor of Ca(2+)/calmodulin-dependent protein kinase kinase (CaMKK). The results from the molecular docking assays and experiments targeting the AMPK gamma 1 subunit with siRNA indicated that WS010117 may activate AMPK by binding to and regulating the gamma subunit of AMPK. Significance: Our data indicate that WS010117 can regulate lipid metabolism through the activation of AMPK. WS010117 may activate AMPK by binding to and regulating the AMPK gamma subunit. (C) 2011 Elsevier Inc. All rights reserved.