Plasma concentrations of lysophosphatidic acid and the expression of its receptors in peripheral blood mononuclear cells are altered in patients with cocaine use disorders.

We have recently reported alterations in the plasma concentrations of lysophosphatidic acid (LPA) in patients with substance use disorders. In order to further explore the potential role of the LPA signaling system as biomarker in cocaine use disorders (CUD) we conducted a cross-sectional study with 105 patients diagnosed with CUD and 92 healthy controls. Participants were clinically evaluated and blood samples were collected to determine plasma concentrations of total LPA and LPA species (16:0-, 18:0-, 18:1-, 18:2-, and 20:4-LPA), and the gene expression of LPA1 and LPA2 receptors in peripheral blood mononuclear cells. We found that patients with CUD had significantly lower plasma concentration of the majority of LPA species, while the mRNA expression of LPA1 receptor was found to be higher than controls. Moreover, we found a positive association between plasma concentration of 20:4-LPA and relevant CUD-related variables: age of onset cocaine use and length of cocaine abstinence. The statistical analysis revealed sex differences in concentrations of total LPA and LPA species, and women showed higher LPA concentrations than men. Furthermore, studies in rats of both sexes showed that plasma concentrations of total LPA were also altered after acute and chronic cocaine administration, revealing a sexual dimorphism in these effects. This study found alterations on the LPA signaling system in both, patients with CUD and rats treated with cocaine. Our results demonstrate that LPA signaling is impacted by CUD and sex, which must be taken into consideration in future studies evaluating LPA as a reliable biomarker for CUD.

Is Metacognitive Training effective for improving neurocognitive function in patients with a recent onset of psychosis?

The aims are to assess improvements in memory, attention and executive function in first-episode psychosis after Metacognitive Training (MCT). A multicenter randomized clinical trial was performed with two arms: MCT and psychoeducational intervention. A total of 126 patients with a diagnosis of psychosis, less than 5 years from the onset of the disease, were included. Patients were assessed two or three moments (baseline, post-treatment, 6 months follow-up) depending on the test, with a battery of neurocognitive tests (TAVEC, TMTA-B, CPT, WCST, Stroop and premorbid IQ). General linear models for repeated measures were performed.  A better improvement in the MCT was found by an interaction between group and time in CPT Hit index, TMTB, Stroop, recent memory and number of perseverations of the TAVEC. Considering three assessments, a better improvement was found in non-perseverative, perseverative and total errors of the WCST and TMTB. The MCT is an effective psychological intervention to improve several cognitive functions.