Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Acute exposure to low glucose rapidly induces endothelial dysfunction and mitochondrial oxidative stress: role for AMP kinase. Arterioscler Thromb Vasc Biol 2012 Mar;32(3):712-20

Date

12/31/2011

Pubmed ID

22207730

Pubmed Central ID

PMC3319449

DOI

10.1161/ATVBAHA.111.227389

Scopus ID

2-s2.0-84857657883   75 Citations

Abstract

OBJECTIVE: Hypoglycemia is associated with increased mortality. The reasons for this remain unclear, and the effects of low glucose exposure on vascular endothelial function remain largely unknown. We endeavored to determine the effects of low glucose on endothelial cells and intact human arterioles.

METHODS AND RESULTS: We exposed human umbilical vein endothelial cells to low glucose conditions in a clinically relevant range (40-70 mg/dL) and found rapid and marked reductions in nitric oxide (NO) bioavailability (P<0.001). This was associated with concomitantly increased mitochondrial superoxide production (P<0.001) and NO-dependent mitochondrial hyperpolarization (P<0.001). Reduced NO bioavailability was rapid and attributable to reduced endothelial nitric oxide synthase activity and destruction of NO. Low glucose rapidly activated AMP kinase, but physiological activation failed to restore NO bioavailability. Pharmacological AMP kinase activation led to phosphorylation of endothelial nitric oxide synthase's Ser633 activation site, reversing the adverse effects of low glucose. This protective effect was prevented by L-NG-Nitroarginine methyl ester. Intact human arterioles exposed to low glucose demonstrated marked endothelial dysfunction, which was prevented by either metformin or TEMPOL.

CONCLUSION: Our data suggest that moderate low glucose exposure rapidly impairs NO bioavailability and endothelial function in the human endothelium and that pharmacological AMP kinase activation inhibit this effect in an NO-dependent manner.

Author List

Wang J, Alexanian A, Ying R, Kizhakekuttu TJ, Dharmashankar K, Vasquez-Vivar J, Gutterman DD, Widlansky ME

Authors

David D. Gutterman MD Sr Associate Director, Professor in the Medicine department at Medical College of Wisconsin
Michael E. Widlansky MD Associate Director, Professor in the Medicine department at Medical College of Wisconsin




MESH terms used to index this publication - Major topics in bold

AMP-Activated Protein Kinases
Adipose Tissue
Antioxidants
Arterioles
Cells, Cultured
Endothelium, Vascular
Enzyme Activation
Enzyme Activators
Enzyme Inhibitors
Glucose
Human Umbilical Vein Endothelial Cells
Humans
Hypoglycemia
Hypoglycemic Agents
Membrane Potential, Mitochondrial
Mitochondria
Nitric Oxide
Nitric Oxide Synthase Type III
Oxidative Stress
Phosphorylation
Serine
Signal Transduction
Superoxides
Time Factors
jenkins-FCD Prod-484 8aa07fc50b7f6d102f3dda2f4c7056ff84294d1d