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A recent study by Funahashi et al. explores the expression of miRNA in schizophrenia patients, providing valuable insights into potential biomarkers and treatment effects. The study suggests that miR-675-3p is upregulated in patients with treatment-resistant schizophrenia (TRS) who are treated with clozapine. However, caution is needed when interpreting these findings, as the upregulation of miR-675-3p may be a feature of TRS itself rather than a specific effect of clozapine. The study also compares miRNA expression in non-TRS patients treated with antipsychotics other than clozapine, but the lack of detailed information on specific antipsychotic regimens introduces a significant variable. Further research is needed to separate the effects of the disease from the effects of treatment and to better understand clozapine's specific influence on miRNA expression in TRS. [Extracted from the article]

Abstract: Schizophrenic patients have cognitive impairments, but gender differences in these cognitive deficits have had limited study. This study assessed cognitive functioning in 471 subjects including 122 male and 78 female schizophrenic patients and 141 male and 130 female healthy controls. We found that immediate memory, language, delayed memory and total RBANS scores were significantly decreased in schizophrenia compared with healthy controls for both genders. Male patients had significant lower immediate memory, delayed memory and total RBANS scores than female patients, and healthy controls showed a similar gender difference. The RBANS showed modest correlations with PANSS scores, duration of illness and antipsychotic dose (chlorpromazine equivalents). Almost all RBANS scores in the schizophrenics and healthy controls showed significant positive correlations with education. Thus, patients of both sexes with schizophrenia experienced more deteriorated performance than healthy controls on cognitive domains of immediate memory, language and delayed memory. Furthermore, male schizophrenic patients had more serious cognitive deficits than female patients in immediate and delayed memory, but not in language, visuospatial and attention indices. [Copyright &y& Elsevier]

Objective: The purpose of this study was to investigate the lifetime suicide attempt rate, clinical characteristics and cognitive function of Chinese patients with chronic schizophrenia who had attempted suicide. Methods: We collected data from 908 schizophrenia inpatients about suicide attempts through interviews with the patients and their families, as well as through medical records. All patients were assessed with the Positive and Negative Syndrome Scale, the Rating Scale for Extrapyramidal Side Effects, the Abnormal Involuntary Movement Scale, and the Repeated Battery for the Assessment of Neuropsychological Status. Results: Of this sample, 97 (10.68%) had attempted suicide. Patients who had attempted suicide were younger, had longer illness duration, and more severe general psychopathology and depressive symptoms than those who had not. Logistic regression analysis confirmed that suicide attempts were correlated with age, smoking, and depression. No cognitive performance differences were observed between patients who had and had not attempted suicide. Conclusions: In China, patients with chronic schizophrenia may have a higher prevalence of lifetime suicide attempts than the general population. Some demographic and clinical variables were related to suicide attempts in patients with chronic schizophrenia. [ABSTRACT FROM AUTHOR]

Neural cell adhesion molecule (NCAM) plays an important role in neurodevelopmental processes and regulates hippocampal plasticity. This study investigated the relationship between the serum NCAM concentrations and hippocampal volume and psychotic symptoms in first-episode drug naïve schizophrenia (FES) patients. Forty-four FES patients and forty-four healthy controls (HC) were recruited in this study. Serum concentrations of NCAM were measured by ELISA. Psychiatric symptoms were assessed by the positive and negative syndrome scale (PANSS). Brain structural images were obtained using a 3T MRI Scanner and obtained T1 images were processed in order to determine hippocampal grey matter volumes. Schizophrenia patients revealed significantly decreased serum NCAM concentrations (p = 0.017), which were positively correlated with the left (r = 0.523, p < 0.001) and right (r = 0.449, p = 0.041) hippocampal volumes, but negatively correlated with the PANSS positive symptom scores (r = −0.522 p = 0.001). However, no such correlations existed in the HC group. This is the first time to report that decreased serum NCAM concentrations were associated with hippocampal volumes and symptom severity in FES patients. Our data indicate that the low NCAM is possible neuropathology that is associated with the decreased hippocampus in FES patients. [ABSTRACT FROM AUTHOR]

Long-term antipsychotic treatment for schizophrenia is associated with the development of tardive dyskinesia (TD), which is involved in increased cognitive impairment. Dopamine beta-hydroxylase (DBH) gene associated with dopamine and norepinephrine systems influences cognition. Schizophrenia with TD have higher DBH activity than those without TD. This study examined whether DBH5'-insertion/deletion (-Ins/Del) polymorphism could influence cognitive function in schizophrenia with and without TD. The presence of DBH5'-Ins/Del polymorphism was determined in 345 schizophrenia with TD and 397 schizophrenia without TD. The Abnormal Involuntary Movement Scale and Repeatable Battery for Assessment of Neuropsychological Status (RBANS) were used to assess TD severity and cognition. The allele and genotype frequencies of DBH5'-Ins/Del polymorphism did not differ between patients with and without TD (both p>0.05). RBANS total score and subscales did not differ by DBH5'-Ins/Del genotype groups in patients with TD (all p>0.05). However, attention score significantly differed by DBH5'-Ins/Del genotype groups in those without TD (p<0.05). Patients without TD who were Del homozygous had significantly lower attention score than those without TD who were Ins alleles (p<0.05). Immediate memory and attention scores were lower in patients with TD than without TD (both p<0.05). This study indicated that DBH5'-Ins/Del polymorphism may not play a role in the susceptibility to TD and cognitive deficits in schizophrenia with TD, but it may influence cognitive function in schizophrenia with non-TD. Moreover, schizophrenia with TD experienced greater cognitive deficits than those with non-TD, especially in immediate memory and attention. [ABSTRACT FROM AUTHOR]

Metabotropic glutamate receptor 5 (mGluR5) is involved in hippocampal-dependent learning and memory, which are processes disrupted in schizophrenia. Recent evidence from human genetic and animal studies suggests that the regulation of mGluR5, including its interaction with trafficking molecules, may be altered in the disorder. However there have been no investigations of hippocampal mGluR5 or mGluR5 trafficking molecules in the postmortem schizophrenia brain to confirm this. In the present study, we investigated whether protein expression of mGluR5, as well as Norbin and Tamalin (modulators of mGluR5 signalling and trafficking), might be altered in the schizophrenia brain, using postmortem samples from the hippocampal CA1 region of schizophrenia subjects and matched controls (n = 20/group). Protein levels of mGluR5 (total: 42%, p < 0.001; monomer: 25%, p = 0.011; dimer: 52%, p < 0.001) and mGluR5 trafficking molecules (Norbin: 47%, p < 0.001; Tamalin: 34%, p = 0.009) were significantly higher in schizophrenia subjects compared to controls. To determine any influence of antipsychotic drug treatment, all proteins were also correlated with lifetime chlorpromazine equivalents in patients, and separately measured in the hippocampus of rats exposed to haloperidol or olanzapine treatment. mGluR5 was negatively correlated with lifetime antipsychotic drug exposure in schizophrenia patients, suggesting antipsychotic drugs could reduce mGluR5 protein in schizophrenia subjects. In contrast, mGluR5 and mGluR5 trafficking molecules were not altered in the hippocampus of antipsychotic drug treated rats. This investigation provides strong support for the hypothesis that mGluR5 is involved in the pathology of schizophrenia, and that alterations to mGluR5 trafficking might contribute to the hippocampal-dependent cognitive dysfunctions associated with this disorder. [ABSTRACT FROM AUTHOR]

Immune deregulation has been postulated to be one of the mechanisms underlying the pathogenesis of tardive dyskinesia (TD). We hypothesized that interleukins would have a link with TD in schizophrenia patients. In this study, the serum IL-2, IL-6 and IL-8 levels were examined by enzyme-linked immunosorbent assay (ELISA) in schizophrenia patients with TD (n = 48) and without TD (n = 45), and healthy controls (n = 44). The psychopathological symptoms of schizophrenia were assessed by the Positive and Negative Syndrome Scale (PANSS). The severity of TD was evaluated using Abnormal Involuntary Movement Scale (AIMS). The results showed that serum IL-2, IL-6 and IL-8 levels were significantly different among schizophrenia patients with TD and without TD and normal controls. Moreover, IL-2 level was significantly correlated with PANSS positive subscale and general subscale in patients with TD and without TD. In addition, IL-2 level was positively correlated with AIMS score in TD patients. The results supported that immune disturbance is related to the schizophrenia patients, especially to the patients with TD and ILs might play an important role in the pathophysiology of schizophrenia patients with TD. [ABSTRACT FROM AUTHOR]