Progress in neuro-psychopharmacology & biological psychiatry
-
Prog. Neuropsychopharmacol. Biol. Psychiatry · Aug 2013
ReviewMonoamine neurocircuitry in depression and strategies for new treatments.
Extensive studies showed that monoaminergic neurotransmission that involves serotonin (5-HT), norepinephrine (NE) and dopamine (DA) exerts major influence on brain circuits concerned by the regulation of mood, reactivity to psychological stress, self-control, motivation, drive, and cognitive performance. Antidepressants targeting monoamines directly affect the functional tone of these circuits, notably in limbic and frontocortical areas, and evidence has been provided that this action plays a key role in their therapeutic efficacy. Indeed, at least some of functional changes detected by functional magnetic resonance imaging in emotion- and cognitive-related circuits such as the one involving limbic-cortical-striatal-pallidal-thalamic connections in depressed patients can be reversed by monoamine-targeted antidepressants. ⋯ In particular, 5-HT systems were shown to exert negative influence on NE and DA systems through 5-HT2A and 5-HT2C receptor- mediated mechanisms, respectively. On the other hand, complex positive and negative influences of NE system on 5-HT neurotransmission are mediated through α1- and α2-adrenergic receptors, respectively. These data provided a rationale for the design of new, multimodal, therapeutic strategies involving drugs acting not only at the "historical" targets such as the 5-HT and/or the NE transporter, but also at other molecular targets to improve their efficacy and their tolerability.
-
Prog. Neuropsychopharmacol. Biol. Psychiatry · Aug 2013
Meta AnalysisWhite matter deficits in first episode schizophrenia: an activation likelihood estimation meta-analysis.
Diffusion tensor imaging (DTI) has been widely used in psychiatric research and has provided evidence of white matter abnormalities in first episode schizophrenia (FES). The goal of the present meta-analysis was to identify white matter deficits by DTI in FES. ⋯ The current findings provide evidence confirming the lack of connection in the fronto-limbic circuitry at the early stages of the schizophrenia. Because the coordinates reported in the primary literature were highly variable, future investigations with large samples would be required to support the identified white matter changes in FES.
-
Prog. Neuropsychopharmacol. Biol. Psychiatry · Aug 2013
Meta AnalysisMeta-analysis: aerobic exercise for the treatment of anxiety disorders.
This meta-analysis investigates the efficacy of exercise as a treatment for DSM-IV diagnosed anxiety disorders. ⋯ Current evidence does not support the use of aerobic exercise as an effective treatment for anxiety disorders as compared to the control conditions. This remains true when controlling for length of exercise sessions and type of anxiety disorder. Future studies evaluating the efficacy of aerobic exercise should employ larger sample sizes and utilize comparison interventions that control for exercise time.
-
Prog. Neuropsychopharmacol. Biol. Psychiatry · Aug 2013
Neural correlate of impulsivity in subjects at ultra-high risk for psychosis.
Impulsivity is one of the most commonly reported behavioral characteristics of patients with schizophrenia. Although there is accumulating evidence regarding behavioral problems in individuals at ultra-high risk (UHR) for psychosis, as yet, no study has reported on impulsivity in this population. The aim of the present study was to assess impulsivity in UHR subjects and to investigate the associated gray matter correlates. ⋯ These results suggest that impulsivity in UHR subjects may reflect altered integrated conflict processing, which likely stems from abnormalities in the ACC, rather than altered reward/punishment processing or executive control.
-
Prog. Neuropsychopharmacol. Biol. Psychiatry · Aug 2013
Combination of prenatal immune challenge and restraint stress affects prepulse inhibition and dopaminergic/GABAergic markers.
Gestational immune challenge with the viral-like antigen poly I:C is a well-established neurodevelopmental model of schizophrenia. However, exposure to inflammation during early life may sensitize the developing brain to secondary insults and enhance the central nervous system vulnerability. To gain a better understanding of the pathophysiology of schizophrenia, we thus developed a two-hit animal model based on prenatal poly I:C immune challenge followed by restraint stress in juvenile mice. ⋯ Likewise, the combination of both insults reduced the mRNA and protein expression levels of the 67 kDa form of glutamic acid decarboxylase (GAD67), in those two brain regions. To our knowledge, this two-hit animal model is the first in vivo model reporting PPI deficits at pubertal age. This two-hit animal model may also help in studying innovative therapies dedicated to the treatment of schizophrenia, especially in its early phase.