Omega-3 fatty acid supplementation changes intracellular phospholipase A2 activity and membrane fatty acid profiles in individuals at ultra-high risk for psychosis.

The identification of an ultra-high risk (UHR) profile for psychosis and a greater understanding of its prodrome have led to increasing interest in early intervention to delay or prevent the onset of psychotic illness. In a randomized placebo-controlled trial, we have identified long-chain ω-3 (ω-3) polyunsaturated fatty acid (PUFA) supplementation as potentially useful, as it reduced the rate of transition to psychosis by 22.6% 1 year after baseline in a cohort of 81 young people at UHR of transition to psychosis. However, the mechanisms whereby the ω-3 PUFAs might be neuroprotective are incompletely understood. Here, we report on the effects of ω-3 PUFA supplementation on intracellular phospholipase A2 (inPLA(2)) activity, the main enzymes regulating phospholipid metabolism, as well as on peripheral membrane lipid profiles in the individuals who participated in this randomized placebo-controlled trial. Patients were studied cross-sectionally (n=80) and longitudinally (n=65) before and after a 12-week intervention with 1.2 g per day ω-3 PUFAs or placebo, followed by a 40-week observation period to establish the rates of transition to psychosis. We investigated inPLA(2) and erythrocyte membrane FAs in the treatment groups (ω-3 PUFAs vs placebo) and the outcome groups (psychotic vs non-psychotic). The levels of membrane ω-3 and ω-6 PUFAs and inPLA(2) were significantly related. Some of the significant associations (that is, long-chain ω-6 PUFAs, arachidonic acid) with inPLA(2) activity were in opposite directions in individuals who did (a positive correlation) and who did not (a negative correlation) transition to psychosis. Supplementation with ω-3 PUFA resulted in a significant decrease in inPLA(2) activity. We conclude that ω-3 PUFA supplementation may act by normalizing inPLA(2) activity and δ-6-desaturase-mediated metabolism of ω-3 and ω-6 PUFAs, suggesting their role in neuroprogression of psychosis.

Pituitary volume and early treatment response in drug-naïve first-episode psychosis patients.

BACKGROUND: An early response to antipsychotic treatment in patients with psychosis has been associated with a better course and outcome. However, factors that predict treatment response are not well understood. The onset of schizophrenia and related disorders has been associated with increased levels of stress and hyper-activation of the hypothalamic-pituitary-adrenal (HPA) axis. This study examined whether pituitary volume at the onset of psychosis may be a potential predictor of early treatment response in first-episode psychosis (FEP) patients. METHODS: We investigated the relationship between baseline pituitary volume and symptomatic treatment response over 12 weeks using mixed model analysis in a sample of 42 drug-naïve or early treated FEP patients who participated in a controlled dose-finding study of quetiapine fumarate. Logistic regression was used to examine predictors of treatment response. Pituitary volume was measured from magnetic resonance imaging scans that were obtained upon entry into the trial. RESULTS: Larger pituitary volume was associated with less improvement in overall psychotic symptoms (Brief Psychiatric Rating Scale (BPRS) P=0.031) and positive symptoms (BPRS positive symptom subscale P=0.010). Regardless of gender, patients with a pituitary volume at the 25th percentile (413 mm(3)) were approximately three times more likely to respond to treatment by week 12 than those at the 75th percentile (635 mm(3)) (odds ratio=3.07, CI: 0.90-10.48). CONCLUSION: The association of baseline pituitary volumes with early treatment response highlights the importance of the HPA axis in emerging psychosis. Potential implications for treatment strategies in early psychosis are discussed.

Early-onset of symptoms predicts conversion to non-affective psychosis in ultra-high risk individuals.

OBJECTIVE: We examined if age of onset of psychiatric symptoms and/or sex predict conversion to non-affective or affective psychosis in individuals considered to be at ultra-high risk for schizophrenia. METHOD: Participants (n=86) were offered treatment and monthly follow-up until transition to psychosis, or for 12 months if they did not meet exit criteria for psychotic disorder. Individuals without transition to psychosis at 12-month were reassessed approximately 3 years after the end of the treatment phase. Ultra-high risk was defined by the presence of subthreshold and/or self-limiting psychotic symptoms and/or having a family history of psychotic disorder combined with functional decline. Cox regressions after adjustment for treatment interventions were applied to investigate associations between age of onset, sex, and other baseline measures with progression to psychotic outcomes. RESULTS: Early age of onset of psychiatric symptoms, in particular onset before age 18 was the only tested variable that significantly predicted non-affective psychosis. Independent significant predictors of affective psychosis were poor functioning, female sex and the presence of a combination of intake criteria (family history of psychosis plus drop in functioning, and attenuated and/or brief limited psychotic symptoms) at baseline. CONCLUSIONS: Age of onset of psychiatric symptoms is the single most important factor associated with conversion to non-affective psychosis in ultra-high risk individuals.

The role of phospholipases A2 in schizophrenia.

A range of neurotransmitter systems have been implicated in the pathogenesis of schizophrenia based on the antidopaminergic activities of antipsychotic medications, and chemicals that can induce psychotic-like symptoms, such as ketamine or PCP. Such neurotransmitter systems often mediate their cellular response via G-protein-coupled release of arachidonic acid (AA) via the activation of phospholipases A2 (PLA2s). The interaction of three PLA2s are important for the regulation of the release of AA--phospholipase A2 Group 2 A, phospholipase A2 Group 4A and phospholipase A2 Group 6A. Gene variations of these three key enzymes have been associated with schizophrenia with conflicting results. Preclinical data suggest that the activity of these three enzymes are associated with monoaminergic neurotransmission, and may contribute to the differential efficacy of antipsychotic medications, as well as other biological changes thought to underlie schizophrenia, such as altered neurodevelopment and synaptic remodelling. We review the evidence and discuss the potential roles of these three key enzymes for schizophrenia with particular emphasis on published association studies.

Cocaine and benzoylecgonine in saliva, serum, and urine.

We studied the feasibility of using saliva to detect cocaine and benzoylecgonine. Saliva was collected as an ultrafiltrate directly in the mouth with an osmotic device. We analyzed by immunoassay matched samples of urine, blood, and salivary ultrafiltrate from 69 patients who had used cocaine within 24 h of sample collection. Cocaine concentrations were 4.9 times higher in saliva than in serum; benzoylecgonine concentrations were 2.5 times higher in serum. Seven urine and two serum samples had undetectable concentrations of cocaine, but all 69 saliva samples were positive for the drug. For benzoylecgonine detection, all urine samples were positive and three serum and one saliva sample were negative. We also analyzed 43 samples of saliva by gas chromatography/mass spectrometry: all were positive for benzoylecgonine, whereas 40 were positive for cocaine. We conclude that simultaneous measurement of cocaine and benzoylecgonine in saliva is suitable in screening for recent cocaine use.