Correspondence between negative symptoms and potential sources of secondary negative symptoms over time.

There has been a debate in the literature about the distinction between primary and secondary negative symptoms of schizophrenia. Our aim was to study the associations between negative symptoms and potential sources of secondary negative symptoms over time. A sample of 275 participants with at least mid-moderate negative symptoms was randomized into body psychotherapy or Pilates class in a previous study. No significant differences were found between groups over time and changes in the symptom domains were modest. The present investigation considers the longitudinal correlation between variables of interest at baseline, 3 and 9 months follow-up. Measures were the Clinical Assessment Interview for Negative Symptoms (CAINS), the Positive and Negative Symptom Scale (PANSS), the Calgary Depression Scale (CDSS) and the Simpson-Angus Extrapyramidal side-effects Scale (SAS). Mixed models were computed to test the longitudinal association between these variables. In a sensitivity analysis, the dosages of antipsychotic, illness duration and allocated intervention were taken into account. Overall, the course of extrapyramidal side-effects, depressive and positive symptoms was significantly related to the course of negative symptoms. Only extrapyramidal effects were longitudinally correlated to expressive negative symptoms. The sensitivity analyses showed unaltered results for positive symptoms and depression but a lack of association between extrapyramidal effects and the CAINS outcomes. In conclusion, the unambiguous interpretation between primary and secondary negative symptoms may lead to refined treatment approaches for schizophrenia and to increased effects of the interventions.

Protective role of endocannabinoid signaling in an animal model of haloperidol-induced tardive dyskinesia.

Tardive dyskinesia (TD) is a side effect associated with the long-term use of certain antipsychotics. Considering the modulatory role of the endocannabinoid system upon dopaminergic neurotransmission, the present study tested the hypothesis that increasing endocannabinoid (anandamide and 2-arachidonoylglycerol) levels attenuates haloperidol-induced TD (vacuous chewing movements, VCMs) in male Wistar rats. The animals received administration of chronic haloperidol (38 mg/kg; 29 days) followed by acute FAAH (URB597, 0.1-0.5 mg/kg) or MAGL (JZL184, 1-10 mg/kg) inhibitors before VCM quantification. The underlying mechanisms were evaluated by pre-treatments with a CB1 receptor antagonist (AM251, 1 mg/kg) or a TRPV1 channel blocker (SB366791, 1 mg/kg). Moreover, CB1 receptor expression was evaluated in the striatum of high-VCM animals. As expected, haloperidol induced VCMs only in a subset of rats. Either FAAH or MAGL inhibition reduced VCMs. These effects were prevented by CB1 receptor antagonism, but not by TRPV1 blockage. Remarkably, CB1 receptor expression was increased high-VCM rats, with a positive correlation between the levels of CB1 expression and the number of VCMs. In conclusion, increasing endocannabinoid levels results in CB1 receptor-mediated protection against haloperidol-induced TD in rats. The increased CB1 receptor expression after chronic haloperidol treatment suggests a counter-regulatory protective mechanism.

Aripiprazole-Induced Oculogyric Crisis: A Pediatric Case Series and A Brief Narrative Review.

Oculogyric crisis (OGC) represent an unusual type of dystonic movement disorder, usually reported as an adverse event of antipsychotic drugs, with acute or tardive onset, likely due to a functional disruption of dopaminergic neurotransmission. It is seldom reported in children with aripiprazole, an atypical antipsychotic commonly used in youths. In this manuscript, we report on a case series of three pediatric patients and provide a brief narrative review of the literature, in order to increase the awareness of clinicians and to foster future research in this area.