LncRNA RP5-998N21.4 promotes immune defense through upregulation of IFIT2 and IFIT3 in schizophrenia.

Schizophrenia is a complex polygenic disease that is affected by genetic, developmental, and environmental factors. Accumulating evidence indicates that environmental factors such as maternal infection and excessive prenatal neuroinflammation may contribute to the onset of schizophrenia by affecting epigenetic modification. We recently identified a schizophrenia-associated upregulated long noncoding RNA (lncRNA) RP5-998N21.4 by transcriptomic analysis of monozygotic twins discordant for schizophrenia. Importantly, we found that genes coexpressed with RP5-998N21.4 were enriched in immune defense-related biological processes in twin subjects and in RP5-998N21.4-overexpressing (OE) SK-N-SH cell lines. We then identified two genes encoding an interferon-induced protein with tetratricopeptide repeat (IFIT) 2 and 3, which play an important role in immune defense, as potential targets of RP5-998N21.4 by integrative analysis of RP5-998N21.4OE-induced differentially expressed genes (DEGs) in SK-N-SH cells and RP5-998N21.4-coexpressed schizophrenia-associated DEGs from twin subjects. We further demonstrated that RP5-998N21.4 positively regulates the transcription of IFIT2 and IFIT3 by binding to their promoter regions and affecting their histone modifications. In addition, as a general nuclear coactivator, RMB14 (encoding RNA binding motif protein 14) was identified to facilitate the regulatory role of RP5-998N21.4 in IFIT2 and IFIT3 transcription. Finally, we observed that RP5-998N21.4OE can enhance IFIT2- and IFIT3-mediated immune defense responses through activation of signal transducer and activator of transcription 1 (STAT1) signaling pathway in U251 astrocytoma cells under treatment with the viral mimetic polyinosinic: polycytidylic acid (poly I:C). Taken together, our findings suggest that lncRNA RP5-998N21.4 is a critical regulator of immune defense, providing etiological and therapeutic implications for schizophrenia.

Histogenous Hypoxia and Acid Retention in Schizophrenia: Changes in Venous Blood Gas Analysis and SOD in Acute and Stable Schizophrenia Patients.

Background: Oxidative stress may play an important role in the pathogenesis of schizophrenia (SCH), and there is considerable indirect evidence that hypoxia is closely related to SCH, but direct evidence of hypoxia in SCH has never been found. Methods:In this study, superoxide dismutase (SOD), venous blood gas, and Positive and Negative Syndrome Scale (PANSS) were examined in 40 SCH patients and compared with those of 40 healthy controls. The patients were treated with combination of atypical antipsychotics and Ditan Huayu Lishen decoction (a Chinese medicine decoction) and examined in the acute and stable period, respectively. Comparisons of indicators between two groups were performed using an independent-samples t-test, comparison of indicators between the acute and stable periods in the SCH group was performed using paired-samples t-test. Pearson correlation and multiple linear regression analyses were performed to investigate the relationships between the effect indicators. Results: Higher venous pH, PvO2, and fasting blood glucose levels and lower SOD, lactic acid, and PvCO2 levels were found in SCH patients compared with the control group; SOD was negatively correlated with the general psychopathology subscale score (PANSS-G), and PvO2 levels were closely related to venous pH in SCH and related to PvCO2 in the control group. It was also found that SOD activity showed no significant difference in acute and stable period, whereas PvO2 showed a downward trend, and venous pH was decreased significantly after treatment. Both the venous pH and PvO2 were higher in patients with SCH than that in healthy controls. Conclusion: It suggests that histogenous hypoxia and acid retention exist in relation to SCH, and there is an improvement of acid retention and a downward trend in histogenous hypoxia after combination treatment. Venous pH, PvO2, and PvCO2 are trait variables, but not state variables of SCH. The theory of histogenous hypoxia and acid retention can well explain the decrease in pH value and the increase in lactic acid in brain tissue of patients with SCH. Histogenous hypoxia and acid retention closely related to glucose metabolism. So they may play an important role in pathophysiology for SCH.

Sex Differences in the Prevalence and Clinical Features of Comorbid Depressive Symptoms in Never-Treated Chinese Patients With First-Episode Schizophrenia.

BACKGROUND: Many studies have indicated a sex-specific effect in many aspects of schizophrenia. The presence of depressive symptomatology exists in all phases of schizophrenia. The aim of this study is to investigate the sex differences in the proportion of comorbid depressive symptoms and sex-specific relationships between depressive symptoms and clinical correlates in never-treated Chinese patients with first-episode schizophrenia (NTFE patients), which have not been reported yet. METHODS: Via a cross-sectional design, 240 NTFE inpatients (male/female = 111/129) between ages 16 and 45 years and meeting DSM-IV-TR criteria of schizophrenia were recruited. The Positive and Negative Syndrome Scale (PANSS) was used for the psychopathology, and the 17-item Hamilton Depression Rating Scale (HDRS-17) for the comorbid depressive symptoms. This study was conducted from June 2013 to December 2015. RESULTS: The proportion of patients with depressive symptoms (total score on HDRS-17 ≥ 8) in men was significantly higher than in women (male: 62.2%, female: 48.1%; χ²1 = 4.28, P = .039). Male patients had significantly greater depressive symptoms as shown on the HDRS-17 than female patients (t1, 238 = 2.75, P = .006). Further, we found that age, the age at onset, smoking rate, and PANSS total and general psychopathology, negative symptoms, and cognitive factor subscores favored significant sex differences in female patients (all P < .05). Interestingly, we found sex differences in the correlation between the HDRS-17 score and clinical phenotype, showing that in male patients, the PANSS general psychopathology subscore (ß = 0.75, t = 7.72, P < .001) and total score (ß = 0.44, t = 4.81, P < .001) significantly predicted the HDRS-17 total score, while in female patients, the PANSS general psychopathology subscore (ß = 0.74, t = 8.45, P < .001), total score (ß = 0.47, t = 5.71, P < .001), and cognitive factor subscore (ß = 0.24, t = 2.60, P < .001) significantly predicted the HDRS-17 total score. CONCLUSIONS: Our results indicate sex differences in the frequency and severity of comorbid depressive symptoms and in associations between depressive symptoms and clinical correlates in NTFE patients.

The TNF-alpha gene -1031T>C polymorphism is associated with onset age but not with risk of schizophrenia in a Chinese population.

OBJECTIVE: Evidence has shown the importance of tumor necrosis factor alpha (TNF-alpha) in the pathophysiological feature in schizophrenia patients. This study aims to determine the impact of a single-nucleotide polymorphism (SNP) in the TNF-alpha gene promoter on the susceptibility, onset age, and cognitive function of schizophrenia. METHOD: The SNP -1031T>C in the TNF-alpha gene was genotyped in 905 patients and 571 healthy controls. The Positive and Negative Syndrome Scale (PANSS) was used to assess the schizophrenia symptoms and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) for cognitive function. RESULTS: There was no significant difference in allele or genotype distribution of the SNP -1031T>C between patients and controls (p = .85, p = .98). This polymorphism had no significant genotypic effect on the symptomatology assessed by the PANSS. Interestingly, this polymorphism was significantly correlated with onset age in schizophrenia patients (p = .004). We found an earlier onset age in patients with the TT genotype compared to those with the CT and CC genotypes (both p < .05). Moreover, there were significant genotypic effects on the immediate memory index, visuospatial/constructional index, and RBANS total score (all p < 0.05) in the patient group. CONCLUSIONS: Our results suggest that the SNP -1031T>C of the TNF-alpha gene may not be associated with susceptibility to schizophrenia but possibly acts as a modulator for its onset age as well as for cognitive deficits. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Effects of smoking on cognition and BDNF levels in a male Chinese population: relationship with BDNF Val66Met polymorphism.

Recent studies demonstrate that brain-derived neurotrophic factor (BDNF) might be associated with nicotine addiction, and circulating BDNF is a biomarker of memory and general cognitive function. Moreover, studies suggest that a functional polymorphism of the BDNF Val66Met may mediate hippocampal-dependent cognitive functions. We aimed to explore the relationships between smoking, cognitive performance and BDNF in a normal Chinese Han population. We recruited 628 male healthy subjects, inducing 322 smokers and 306 nonsmokers, and genotyped them the BDNF Val66Met polymorphism. Of these, we assessed 114 smokers and 98 nonsmokers on the repeatable battery for the assessment of neuropsychological status (RBANS), and 103 smokers and 89 nonsmokers on serum BDNF levels. Smokers scored lower than the nonsmokers on RBANS total score (p = 0.002), immediate memory (p = 0.003) and delayed memory (p = 0.021). BDNF levels among the smokers who were Val allele carriers were correlated with the degree of cognitive impairments, especially attention, as well as with the carbon monoxide concentrations. Our findings suggest that smoking is associated with cognitive impairment in a male Chinese Han population. The association between higher BDNF levels and cognitive impairment, mainly attention in smokers appears to be dependent on the BDNF Val66Met polymorphism.