Glutamate in CNS neurodegeneration and cognition and its regulation by GCPII inhibition.
Glutamate, first identified in 1866, is the primary excitatory neurotransmitter in the brain. While it is critically important in many highly regulated cortical functions such as learning and memory, glutamate can be much like the magic the Sorcerer's Apprentice used in Goethe's poem: when conjured under unregulated conditions glutamate can get quickly out of control and lead to deleterious consequences. Two broad types of glutamate receptors, the ionotropic and metabotropic, facilitate glutamatergic neurotransmission in the CNS and play key roles in regulating cognitive function. Excessive activation of these receptors leads to excitotoxicity, especially in brain regions that are developmentally and regionally vulnerable to this kind of injury. Dysregulation of glutamate signaling leads to neurodegeneration that plays a role in a number of neuropsychiatric diseases, prompting the development and utilization of novel strategies to balance the beneficial and deleterious potential of this important neurotransmitter. Inhibition of the enzyme glutamate carboxypeptidase II (GCPII) is one method of manipulating glutamate neurotransmission. Positive outcomes (decreased neuronal loss, improved cognition) have been demonstrated in preclinical models of ALS, stroke, and Multiple Sclerosis due to inhibition of GCPII, suggesting this method of glutamate regulation could serve as a therapeutic means for treating neurodegeneration and cognitive impairment.
Department of Psychiatry, Johns Hopkins University, Baltimore, MD, USA.
K A
KA
Rahn
B S
BS
Slusher
A I
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Kaplin
D000818:Animals; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D002493:Central Nervous System Diseases / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003071:Cognition / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D043425:Glutamate Carboxypeptidase II / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D006801:Humans; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use; D009435:Synaptic Transmission / Q000187:drug effects
D004791:Enzyme Inhibitors; D018696:Neuroprotective Agents; D018698:Glutamic Acid; D043425:Glutamate Carboxypeptidase II