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Deprivation of sleep (DS) and its effects on circadian rhythm gene expression are not well understood despite their influence on various physiological and psychological processes. This study aimed to elucidate the changes in the expression of circadian rhythm genes following a night of sleep and DS. Their correlation with sleep architecture and physical activity was also examined. The study included 81 participants who underwent polysomnography (PSG) and DS with actigraphy. Blood samples were collected after PSG and DS. Expression levels of brain and muscle ARNT-like 1 (BMAL1), circadian locomotor output cycles kaput (CLOCK), neuronal PAS domain protein 2 (NPAS2), period 1 (PER1), cryptochrome 1 (CRY1) and nuclear receptor subfamily 1 group D member 1 (NR1D1) were analyzed using qRT-PCR. DS decreased the expression of CLOCK and BMAL1 while increasing PER1. PER1 expression correlated positively with total sleep time and non-rapid-eye-movement (NREM) sleep duration and negatively with sleep latency, alpha, beta and delta waves in the O1A2 lead. Physical activity during DS showed positive correlations with CLOCK, BMAL1, and CRY1. The findings highlight the role of PER1 in modulating sleep patterns, suggesting potential targets for managing sleep-related disorders. Further research is essential to deepen the understanding of these relationships and their implications. [ABSTRACT FROM AUTHOR]

Objective: Modulation of glutamatergic neurotransmission in schizophrenia by sarcosine leads to a reduction in primary negative symptoms, while its metabolic profile is safe. In order to extend research in the area, we assessed serum levels of neuropeptide Y (NPY), a hypothalamic hormone related to anxiety and depression, also involved in mechanisms inducing weight gain. Additionally, we analyzed associations between NPY concentrations and its changes with severity of symptoms and metabolic parameters. Methods: A prospective 6‐month, randomized, double‐blind placebo‐controlled trial was completed by 57 subjects with chronic schizophrenia with predominant negative symptoms and stable antipsychotic treatment. The participants received 2 g of sarcosine (n = 28) or placebo (n = 29) daily. We assessed serum NPY concentrations and severity of symptoms (with the Positive and Negative Syndrome Scale [PANSS] and Calgary Depression Scale for Schizophrenia) at the beginning of the study, after 6 weeks and 6 months. Results: Sarcosine did not affect NPY levels in all time points. The highest decrease in NPY concentrations was observed in the subjects who were initially depressed, who became euthymic at the last visit. We noticed an improvement in the total PANSS score, and negative symptom and general psychopathology subscales in the sarcosine group, however, without any correlation with NPY levels. Conclusion: The use of sarcosine does not change NPY levels. Peripheral NPY concentrations may be related to depressive symptoms in schizophrenia. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to determine the mRNA expression profile of dopamine D1, D2, D3, D4 and serotonin 5-HT1A, 5-HT2A, and 5-HT3A receptors in peripheral blood mononuclear cells (PBMCs) in schizophrenia and the in vitro effect of antipsychotics on the expression of these receptors in PBMCs of healthy subjects. Materials and Methods: Twenty-seven patients with schizophrenia and 29 healthy controls were recruited for the study. All study subjects underwent thorough clinical assessment, including anthropometric and body composition measurements. The expression of mRNA for dopamine D1−4 and serotonin 5-HT1A−3A receptors was measured using quantitative RT-PCR in peripheral blood mononuclear cells. In vitro mRNA and protein expression of these receptors was measured using quantitative RT-PCR and Western Blotting in PBMCs cultured with quetiapine, haloperidol, aripiprazole, risperidone, olanzapine or clozapine at IC50, half of IC50, and one-quarter of IC50 concentrations. Results: The key finding was that the schizophrenia group demonstrated significantly higher mRNA expression of D1, D2 and D4 receptors (p < 0.001), and significantly lower mRNA expression of 5-HT3A receptors (p < 0.01). After adjusting for smoking, the mRNA expression of D1 lost its significance, while that of D3, 5-HT1A, 5-HT2A became significant (all three were lower in the schizophrenia group). These receptors also demonstrated different ratios of mRNA expression in the schizophrenia group. The in vitro experiments showed that high concentrations of antipsychotics influenced the mRNA and protein expression of all studied receptors. Conclusion: Schizophrenia patients display a distinctive pattern of dopamine and serotonin receptor mRNA expression in blood mononuclear cells. This expression is little affected by antipsychotic treatment and it may therefore serve as a useful diagnostic biomarker for schizophrenia. [ABSTRACT FROM AUTHOR]

It has been suggested that immune-inflammatory processes might be involved in the etiopathogenesis of schizophrenia. Since growing evidence indicates that adipokines strongly modulate the course of immune response and inflammatory processes, it is currently suggested the contribution of those factors in the etiology of schizophrenia as well. The aim of this study was to determine the serum levels of 4 adipokines-apelin, resistin, chemerin, and omentin-in patients with schizophrenia as compared with healthy subjects. Fifty-seven adult patients with schizophrenia and 31 healthy volunteers were included in this prospective study. ELISA was used to measure the serum concentration of resistin, apelin, omentin-1, and chemerin. No difference in the mean concentration of resistin (p=0.20) and chemerin (p=0.30) between patients with schizophrenia and the healthy group was observed. Apelin concentration was significantly (p=0.004) lower in patients with schizophrenia as compared with controls. A significant difference in apelin level between men with schizophrenia and control group (p=0.04) was reported. Apelin concentration was significantly correlated with waist-to-hip ratio, whereas chemerin concentration was significantly correlated with the Positive and Negative Syndrome Scale G score. There exists evidence that apelin might be involved in the pathogenesis of schizophrenia. [ABSTRACT FROM AUTHOR]