5′ adenosine monophosphate-activated protein kinase (AMPK)

5′ adenosine monophosphate-activated protein kinase (AMPK) is a highly conserved serine/threonine kinase that functions as a central regulator of cellular and whole-body energy homeostasis. It acts as an energy sensor, becoming activated in response to low cellular ATP levels and increased AMP or ADP concentrations. AMPK is a heterotrimeric complex composed of three subunits: α catalytic, β regulatory, and γ regulatory. Activation occurs through allosteric binding of AMP/ADP to the γ subunit and phosphorylation at Thr172 on the α subunit by upstream kinases such as LKB1 or CaMKKβ. Upon activation during energy stress, AMPK shifts metabolism toward processes that generate ATP while inhibiting those that consume it.

Pharmacological activation improves blood glucose homeostasis, cholesterol levels, and blood pressure. AMPK activators mimic the effects of energy stress, shifting metabolism towards ATP-generating processes.