AMPK as a central regulator of necroptosis: mechanistic insights and therapeutic implications.

Abstract

Adenosine monophosphate-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase that links cellular energy stress with metabolic adaptation, autophagy, redox homeostasis, and cell fate decisions. Necroptosis is a regulated lytic form of cell death driven by receptor-interacting serine/threonine kinases 1 and 3 (RIPK1 and RIPK3), with mixed lineage kinase domain-like protein (MLKL) serving as the terminal executor. Increasing evidence suggests that AMPK modulates necroptosis through multiple interconnected mechanisms. AMPK directly phosphorylates RIPK1, thereby influencing necroptotic signaling in a context- and time-dependent manner. Through the AMPK-mTOR axis, AMPK also regulates autophagy and mitophagy, affecting inhibitory control of RIPK1 and autophagic turnover of RIPK3. In parallel, AMPK suppresses necroptosis through SIRT1- and PGAM5-related pathways, limiting necrosome assembly, mitochondrial dysfunction, and Drp1-dependent mitochondrial fission. AMPK further shapes reactive oxygen species (ROS)-associated necroptotic responses through downstream effectors, including mTOR and Nrf2. In this review, we summarize recent advances in the mechanisms by which AMPK regulates necroptosis and highlight unresolved questions, including the cell-type-specific roles of AMPK subunits, the contribution of additional autophagy regulators, the balance between mTORC1-dependent protective signaling and RIPK3 stability, and the in vivo relevance of the AMPK-SIRT1-PGAM5 axis. Clarifying this regulatory network may facilitate the development of therapeutic strategies for necroptosis-related diseases, including metabolic disorders, ischemia-reperfusion injury, and neurodegeneration. Collectively, the available evidence indicates that AMPK acts as a context-dependent regulator of necroptosis rather than a universally protective kinase.