Original sentence: Excitotoxicity is the process by which apoptosis is triggered in neurons by the overactivation of excitatory neurotransmitter receptors such as the NMDA receptor.Excitotoxicity may be involved in stroke.Excitotoxins like NMDA and kainic acid which bind to these receptors can cause excitotoxicity, as can pathologically high levels of glutamate
Edited sentence: Excitotoxins are usually amino acids, such as glutamate and aspartate.Excitotoxins can also cause a loss of brain synapses and connecting fibers.Food-borne excitotoxins include such additives as MSG, aspartame, hydrolyzed protein and soy protein extract.These special amino acids cause particular brain cells to become excessively excited, to the point they will quickly die