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The plasma 5'-AMP acts as a potential upstream regulator of hyperglycemia in type 2 diabetic mice

Ying Zhang1, Zhongqiu Wang, Yue Zhao

  • 1Center for Molecular Metabolism, Nanjing University of Science and Technology, Nanjing, China.

American Journal of Physiology. Endocrinology and Metabolism
|November 10, 2011
PubMed

Insights

Elevated plasma 5'-adenosine monophosphate (pAMP) contributes to hyperglycemia in type 2 diabetes by impairing insulin action and increasing glucose production. This finding reveals a potential molecular link between free fatty acids and diabetic blood sugar control.

Area of Science:

  • Biochemistry
  • Endocrinology
  • Metabolic Diseases

Background:

  • Elevated plasma free fatty acids (FFAs) are characteristic of type 2 diabetes.
  • The molecular mechanisms linking FFAs to hyperglycemia are not fully understood.

Purpose of the Study:

  • To investigate the role of plasma 5 -adenosine monophosphate (pAMP) in FFA-induced hyperglycemia.
  • To elucidate the molecular pathways through which pAMP affects glucose metabolism and insulin action.

Main Methods:

  • Measurement of pAMP levels in type 2 diabetic mice.
  • Assessment of FFA-induced endothelial cell damage and pAMP increase.
  • Administration of synthetic 5 -AMP to wild-type and adenosine receptor-deficient mice.
  • Analysis of glucose levels, insulin sensitivity, GLUT4 translocation, and hepatic gene expression (Foxo1, Pepck, G6Pase).

Main Results:

  • Plasma pAMP was significantly elevated in type 2 diabetic mice.
  • High FFAs damaged vein endothelial cells, increasing pAMP.
  • Synthetic 5 -AMP administration induced hyperglycemia and impaired insulin action, independent of adenosine receptors.
  • pAMP elevated blood glucose by increasing cellular adenosine, stimulating G-6-Pase, inhibiting GLUT4 translocation, and altering hepatic gene expression.

Conclusions:

  • pAMP is identified as a key molecule elevated by FFAs in type 2 diabetes.
  • pAMP directly contributes to hyperglycemia and insulin resistance through multiple molecular mechanisms.
  • pAMP represents a potential upstream regulator and therapeutic target for type 2 diabetes-associated hyperglycemia.

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