title: AMPD1: a novel therapeutic target for reversing insulin resistance.
abstract: BACKGROUND
  Insulin resistance is one of the hallmark manifestations of obesity and Type II diabetes and reversal of this pathogenic abnormality is an attractive target for new therapies for Type II diabetes. A recent report that metformin, a drug known to reverse insulin resistance, demonstrated in vitro the metformin can inhibit AMP deaminase (AMPD) activity. Skeletal muscle is one of the primary organs contributing to insulin resistance and that the AMPD1 gene is selectively expressed at high levels in skeletal muscle.
  
  
  METHODS
  Recognizing the background above, we asked if genetic disruption of the AMPD1 gene might ameliorate the manifestations of insulin resistance. AMPD1 deficient homozygous mice and control mice fed normal chow diet or a high-fat diet, and blood analysis, glucose tolerance test and insulin tolerance test were performed. Also, skeletal muscle metabolism and gene expression including nucleotide levels and activation of AMP activated protein kinase (AMP kinase) were evaluated in both conditions.
  
  
  RESULTS
  Disruption of the AMPD1 gene leads to a less severe state of insulin resistance, improved glucose tolerance and enhanced insulin clearance in mice fed a high fat diet. Given the central role of AMP kinase in insulin action, and its response to changes in AMP concentrations in the cell, we examined the skeletal muscle of the AMPD1 deficient mice and found that they have greater AMP kinase activity as evidenced by higher levels of phosphorylated AMP kinase.
  
  
  CONCLUSIONS
  Taken together these data suggest that AMPD may be a new drug target for the reversal of insulin resistance and the treatment of Type II diabetes.
authors.forename: Jidong
authors.initials: J
authors.lastname: Cheng
authors.forename: Hiroko
authors.initials: H
authors.lastname: Morisaki
authors.forename: Keiko
authors.initials: K
authors.lastname: Toyama
authors.forename: Naomi
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Takuya
authors.initials: T
authors.lastname: Shintani
authors.forename: Andreas
authors.initials: A
authors.lastname: Tandelilin
authors.forename: Tetsuaki
authors.initials: T
authors.lastname: Hirase
authors.forename: Edward W
authors.initials: EW
authors.lastname: Holmes
authors.affiliation: Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan. morisaki@ri.ncvc.go.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Morisaki
mesh_terms: D000659:AMP Deaminase / Q000235:genetics* / Q000378:metabolism*; D055372:AMP-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology / Q000378:metabolism*; D059305:Diet, High-Fat; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D007333:Insulin Resistance / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D009765:Obesity / Q000209:etiology / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D055372:AMP-Activated Protein Kinases; D000659:AMP Deaminase; C577245:AMPD1 protein, mouse