Developments in the pharmacological treatment of schizophrenia

Multi-target strategies for the improved treatment of depressive states: Conceptual foundations and neuronal substrates, drug discovery and therapeutic application

Major depression is a debilitating and recurrent disorder with a substantial lifetime risk and a high social cost. Depressed patients generally display co-morbid symptoms, and depression frequently accompanies other serious disorders. Currently available drugs display limited efficacy and a pronounced delay to onset of action, and all provoke distressing side effects. Cloning of the human genome has fuelled expectations that symptomatic treatment may soon become more rapid and effective, and that depressive states may ultimately be "prevented" or "cured". In pursuing these objectives, in particular for genome-derived, non-monoaminergic targets, "specificity" of drug actions is often emphasized. That is, priority is afforded to agents that interact exclusively with a single site hypothesized as critically involved in the pathogenesis and/or control of depression. Certain highly selective drugs may prove effective, and they remain indispensable in the experimental (and clinical) evaluation of the significance of novel mechanisms. However, by analogy to other multifactorial disorders, "multi-target" agents may be better adapted to the improved treatment of depressive states. Support for this contention is garnered from a broad palette of observations, ranging from mechanisms of action of adjunctive drug combinations and electroconvulsive therapy to "network theory" analysis of the etiology and management of depressive states. The review also outlines opportunities to be exploited, and challenges to be addressed, in the discovery and characterization of drugs recognizing multiple targets. Finally, a diversity of multi-target strategies is proposed for the more efficacious and rapid control of core and co-morbid symptoms of depression, together with improved tolerance relative to currently available agents.

Tardive Dyskinesia: analysis of outpatients with schizophrenia from Africa and the Middle East, Asia, Central and Eastern Europe, and Latin America

The point prevalence of Tardive Dyskinesia (TD) in schizophrenia outpatients (n=6981) participating in a study of health outcomes was 8.9%. Duration of diagnosis, age, and prior use of typical antipsychotics were diagnostic indicators of TD in this population, with male sex further increasing risk. This study provides new data in a non-Western population with a unique regional geography comparison.

Association of DRD2 gene variant with schizophrenia

Schizophrenia is a complex multifactorial disorder for which the pathobiology still remains elusive. Dysfunction of the dopamine D2 receptor signaling has been associated with the illness, but numerous studies provide confounding results. This study investigates the association of synonymous polymorphisms (His313 and Pro319) in the dopamine D2 receptor gene with schizophrenia using a case-control approach, with 101 cases and 145 controls. Our results demonstrated that genotype distribution for the His313 polymorphism was significantly different between schizophrenia patients and control subjects (p=0.0012), while the Pro319 polymorphism did not show any association with the disease. The results suggest that the synonymous SNP His313 in DRD2 may be associated with the illness. However, there is a need for further replication studies with larger sample sets.