Type 2 diabetes is characterized by abnormal metabolism of
glucose and fat, due in part to resistance to the actions of
insulin in peripheral tissues. If untreated it leads to several complications such as
blindness,
kidney failure, neuropathy and
amputations. The benefit of exercise in diabetic patients is well known and recent research indicates that
AMP activated protein kinase (AMPK) plays a major role in this exercise related effect. AMPK is considered as a master switch regulating
glucose and lipid metabolism. The AMPK is an
enzyme that works as a fuel gauge, being activated in conditions of high energy
phosphate depletion. AMPK is also activated robustly by skeletal muscle contraction and myocardial ischaemia, and is involved in the stimulation of
glucose transport and
fatty acid oxidation produced by these stimuli. In liver, activation of AMPK results in enhanced
fatty acid oxidation and decreased production of
glucose,
cholesterol, and
triglycerides. The two leading diabetic drugs namely,
metformin and
rosiglitazone, show their metabolic effects partially through AMPK. These data, along with evidence from studies showing that chemical activation of AMPK in vivo with 5-aminoimidazole-4-carboxamide ribonucleoside (
AICAR) improves
blood glucose concentrations and
lipid profiles, make this
enzyme an attractive pharmacological target for the treatment of
type 2 diabetes and other metabolic disorders.