Use of Cells Expressing gamma Subunit Variants to Identify Diverse Mechanisms of AMPK Activation

Simon A. Hawley, Fiona A. Ross, Cyrille Chevtzoff, Kevin A. Green, Ashleigh Evans, Sarah Fogarty, Mhairi C. Towler, Laura J. Brown, Oluseye A. Ogunbayo, A. Mark Evans, D. Grahame Hardie (Lead / Corresponding author)

    Research output: Contribution to journalArticlepeer-review

    517 Citations (Scopus)

    Abstract

    A wide variety of agents activate AMPK, but in many cases the mechanisms remain unclear. We generated isogenic cell lines stably expressing AMPK complexes containing AMP-sensitive (wild-type, WT) or AMP-insensitive (R531G) gamma 2 variants. Mitochondrial poisons such as oligomycin and dinitrophenol only activated AMPK in WT cells, as did AICAR, 2-deoxyglucose, hydrogen peroxide, metformin, phenformin, galegine, troglitazone, phenobarbital, resveratrol, and berberine. Excluding AICAR, all of these also inhibited cellular energy metabolism, shown by increases in ADP:ATP ratio and/or by decreases in cellular oxygen uptake measured using an extracellular flux analyzer. By contrast, A769662, the Ca2+ ionophore, A23187, osmotic stress, and quercetin activated both variants to varying extents. A23187 and osmotic stress also increased cytoplasmic Ca2+, and their effects were inhibited by ST0609, a CaMKK inhibitor. Our approaches distinguish at least six different mechanisms for AMPK activation and confirm that the widely used antidiabetic drug metformin activates AMPK by inhibiting mitochondrial respiration.

    Original languageEnglish
    Pages (from-to)554-565
    Number of pages12
    JournalCell Metabolism
    Volume11
    Issue number6
    DOIs
    Publication statusPublished - 9 Jun 2010

    Keywords

    • DEPENDENT PROTEIN-KINASE
    • RESPIRATORY COMPLEX-I
    • SIGNALING PATHWAYS
    • ENDOTHELIAL-CELLS
    • GLYCOGEN-STORAGE
    • METFORMIN ACTION
    • MAMMALIAN-CELLS
    • CELLULAR-ENERGY
    • UPSTREAM KINASE
    • SKELETAL-MUSCLE

    Fingerprint

    Dive into the research topics of 'Use of Cells Expressing gamma Subunit Variants to Identify Diverse Mechanisms of AMPK Activation'. Together they form a unique fingerprint.

    Cite this