Benzimidazole derivative small-molecule 991 enhances AMPK activity and glucose uptake induced by AICAR or contraction in skeletal muscle

Research output: Contribution to journalArticle

Authors

  • Laurent Bultot
  • Thomas E. Jensen
  • Agnete L.B. Madsen
  • Caterina Collodet
  • Samanta Kviklyte
  • Maria Deak
  • Arash Yavari
  • Marc Foretz
  • Sahar Ghaffari
  • Mohamed Bellahcene
  • Houman Ashrafian
  • Mark H. Rider
  • Erik A. Richter
  • Kei Sakamoto

Colleges, School and Institutes

External organisations

  • Laboratory of Photonics and Interfaces, Department de Chimie, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland. ahmad@mpip-mainz.mpg.de
  • University of Copenhagen
  • UNIVERSITE CATHOLIQUE DE LOUVAIN
  • OXFORD UNIVERSITY
  • INSERM
  • CNRS-CEA
  • Paris Descartes University

Abstract

AMP-activated protein kinase (AMPK) plays diverse roles and coordinates complex metabolic pathways for maintenance of energy homeostasis. This could be explained by the fact that AMPK exists as multiple heterotrimer complexes comprising a catalytic α-subunit (α1 and α2) and regulatory β (β1 and β2)- and γ (γ1, γ2, γ3)-subunits, which are uniquely distributed across different cell types. There has been keen interest in developing specific and isoform-selective AMPK-activating drugs for therapeutic use and also as research tools. Moreover, establishing ways of enhancing cellular AMPK activity would be beneficial for both purposes. Here, we investigated if a recently described potent AMPK activator called 991, in combination with the commonly used activator 5-aminoimidazole-4-carboxamide riboside or contraction, further enhances AMPK activity and glucose transport in mouse skeletal muscle ex vivo. Given that the γ3-subunit is exclusively expressed in skeletal muscle and has been implicated in contraction-induced glucose transport, we measured the activity of AMPKγ3 as well as ubiquitously expressed γ1-containing complexes. We initially validated the specificity of the antibodies for the assessment of isoform-specific AMPK activity using AMPK-deficient mouse models. We observed that a low dose of 991 (5 µM) stimulated a modest or negligible activity of both γ1- and γ3-containing AMPK complexes. Strikingly, dual treatment with 991 and 5-aminoimidazole- 4-carboxamide riboside or 991 and contraction profoundly enhanced AMPKγ1/γ3 complex activation and glucose transport compared with any of the single treatments. The study demonstrates the utility of a dual activator approach to achieve a greater activation of AMPK and downstream physiological responses in various cell types, including skeletal muscle.

Details

Original languageEnglish
Pages (from-to)E706-E719
Number of pages14
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume311
Issue number4
Publication statusPublished - 1 Oct 2016

Keywords

  • 5-aminoimidazole-4-carboxamide riboside, 991, A769662, AMP-activated protein kinase, Compound 13, Ex229, LKB1