Excitotoxic cascade

The **excitotoxic cascade** is not a single molecule or receptor but rather a pathological process in which neurons are damaged or killed by the overactivation of glutamate receptors—primarily ionotropic types such as NMDA and AMPA receptors. This overactivation leads to excessive calcium influx into neurons, triggering downstream events including activation of destructive enzymes (phospholipases, endonucleases, proteases), oxidative stress, mitochondrial dysfunction, energy failure, cellular swelling from osmotic imbalance, and ultimately cell death through necrosis or apoptosis. The excitotoxic cascade is central to acute CNS injuries like ischemic stroke and traumatic brain injury as well as chronic neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington's disease, multiple sclerosis and ALS. While drugs that modulate this pathway exist—such as NMDA receptor antagonists—they target specific components like the NMDA receptor rather than the entire "cascade," which represents a sequence of molecular events rather than a discrete druggable entity[1][2][3][4]. Because "excitotoxic cascade" refers to an event/pathway—not an individual protein target—it should not be considered a canonical therapeutic target in structured databases. Instead it describes the collective molecular mechanisms underlying excitatory amino acid-induced neuronal damage. > “Excitotoxicity is defined as the process by which neurons are damaged or killed by excessive activation of glutamate receptors... The activation of ionotropic glutamate receptors... is a key step in the excitotoxic cascade.”[1] > “Excitotoxicity is classically defined as neuronal damage caused by excessive release of glutamate... mainly driven by excessive activation of glutamate receptors.”[3]

Other names

ExcitotoxicityExcitotoxic pathwayGlutamate excitotoxicityIschemic cascade (in context of ischemia)

Drugs act by inhibiting glutamate receptors or reducing glutamate release to prevent excessive calcium influx and neuronal damage[3][4].