Zinc as a phase-specific therapeutic target in hypoglycemia-induced brain injury

Hypoglycemia remains a major cause of neurological morbidity. However, effective targeted therapies for affected brain regions remain lacking. Although excitotoxicity and energy failure have long been implicated, emerging evidence has identified dysregulated zinc signaling as a central mediator of neuronal vulnerability and recovery. During acute glucose deprivation, synapse-released zinc accumulates intracellularly, impairing mitochondrial function, activating nicotinamide adenine dinucleotide phosphate oxidase, amplifying oxidative stress, and triggering poly (ADP-ribose) polymerase-dependent cell death pathways. Notably, neuronal injury is markedly exacerbated during glucose reperfusion, when zinc-reactive oxygen species coupling drives metabolic collapse. During the recovery phase, zinc contributes to neurogenesis, synaptic remodeling, and circuit repair, underscoring its phase-dependent duality. Here, we synthesize mechanistic and translational evidence supporting zinc as a dynamic regulator of neuronal fate in hypoglycemia-induced brain injury. We propose that zinc functions as a metabolic switch linking acute oxidative injury to subsequent regenerative processes. Importantly, this framework suggests a precision-timed therapeutic strategy involving acute zinc chelation or inhibition of zinc-coupled oxidative pathways during injury, followed by controlled restoration of zinc-dependent signaling during recovery. By redefining hypoglycemic brain injury through phase-specific zinc modulation, we identify new therapeutic opportunities relevant not only to hypoglycemia but also to broader metabolic and ischemic brain disorders.