Energy provisioning and inflammasome activation: The pivotal role of AMPK in sterile inflammation and associated metabolic disorders
Background: Body defenses and metabolic processes probably co-evolved in such a way that rapid, energyintensive acute inflammatory repair is functionally integrated with energy allocation in a starvation/ infection / injury-prone primitive environment. Disruptive metabolic surplus, aggravated by sedentary lifestyle, induces chronic under-activation of AMPK, the master regulator of intracellular energy homeostasis. Sudden increase in chronic, dysregulated ‘sterile’ inflammatory disorders probably results from a shift towards calorie rich, sanitized, cushioned, injury/ infection free environment, repositioning inflammatory repair pathways towards chronic, non-microbial, ‘sterile’, ‘low grade’, ‘parainflammation’. AMPK, (at the helm of energy provisioning) supervises the metabolic regulation of inflammasome activation, a common denominator in lifestyle disorders. Discussion: In this review we discuss various pathways linking AMPK under-activation and inflammasome activation. AMPK under-activation, the possible norm in energy-rich sedentary lifestyle, could be the central agency that stimulates inflammasome activation by multiple pathways such as: [1] decreasing autophagy, and accumulation of intracellular DAMPs, (particulate crystalline molecules, advanced glycation end-products, oxidized lipids etc.) [2] stimulating a glycolytic shift (pro-inflammatory) in metabolism, [3] promoting NF-kB activation and decreasing Nrf2 activation, [4] increasing reactive oxygen species (ROS) formation, unfolded protein response( UPR) and endoplasmic reticulum (ER) stress. Conclusion: The ‘inverse energy crisis’, associated with calorie-rich, sedentary lifestyle, advocates dietary and pharmacological interventions for treating chronic metabolic disorders by overcoming / reversing AMPK under-activation.