Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Evidence implicating dysfunction of glutamatergic neurotransmission rests largely on the finding that antagonists of the NMDA subtype of glutamate receptor, especially the dissociative anesthetics like ketamine, can reproduce the full range of symptoms as well as the physiologic manifestation of schizophrenia such as hypofrontality, impaired prepulse inhibition and enhanced subcortical dopamine release. To test the hypothesis that schizophrenia may result from NMDA receptor hypofunction a number of clinical trials have examined the effects of agents that act on the glycine modulatory site on the NMDA receptor. Glycine, D-serine, and the partial agonist, D-cycloserine, have been shown to improve cognition and decrease negative symptoms in schizophrenic subjects receiving typical antipsychotics. Results with D-cycloserine suggest that clozapine may enhance glycine modulatory site occupancy. Preliminary results with an allosteric modulator of the AMPA subtype of glutamate receptor suggest enhanced cognitive functions in subjects treated with clozapine.
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PMID:Ionotropic glutamate receptors as therapeutic targets in schizophrenia. 1276 26

Although hypofunction of N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission is proposed to play an important role in the pathophysiology of schizophrenia, results of the clinical trials of small molecules that enhance the NMDA function are inconsistent. A meta-analysis of all the double-blind, placebo-controlled studies in patients with schizophrenia was performed to examine their efficacy on different symptom domains, the dose-response, the effects of concomitant antipsychotics, and their side effects. About eight hundred subjects from 26 studies were included in current meta-analysis. Overall, the NMDA-enhancing molecules are effective in most schizophrenic symptom domains with the effect size (ES) of total psychopathology of 0.40 (p<1 x 10(-4)). The ES of clinical efficacy of the symptom domains were in the order of depressive (0.40, p=3 x 10(-4)), negative (0.38, p<1 x 10(-4)), cognitive (0.28, p=2 x 10(-3)), positive symptom (0.26, p=0.0006), and general psychopathology (0.26, p=0.006). Glycine, D-serine, and sarcosine treatments significantly improved multiple symptom domains, whereas D-cycloserine did not improve any symptom domain. Moderator analysis revealed that glycine, D-serine and sarcosine are better than D-cycloserine in improving the overall psychopathology. Patients receiving risperidone or olanzapine, but not clozapine, improved. No significant side effect or safety concern was noted. In addition to testing more lead compounds, long-term trials are required to determine their functional improvement capacity. Other drug targets that may enhance NMDA neurotransmission more than the molecules tested so far need to be explored.
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PMID:Strategies to enhance N-methyl-D-aspartate receptor-mediated neurotransmission in schizophrenia, a critical review and meta-analysis. 1990 29