A randomized, double-blind, double-dummy, multicenter, controlled trial on brotizolam intervention in outpatients with insomnia.

AIM: To investigate the efficacy and safety of brotizolam in outpatients with insomnia. METHODS: This randomized, double-blind, double-dummy, multicenter, controlled trial recruited 253 outpatients randomized to receive either brotizolam (n = 126) or estazolam (n = 127) for 14 days followed by 1 week of follow-up for rebound detection. Sleep Dysfunction Rating Scale (SDRS) and Clinical General Impression Scale were applied for efficacy evaluation. Safety evaluation was based on data regarding vital signs, physical examination, lab tests, ECG and collection of adverse events. RESULTS: Full Analyses Set (FAS) and Safety Set (SS) included data of 251 subjects, with 126 from brotizolam group and 125 from estazolam group. Per Protocol Set (PPS) analysis included data of 235 subjects, with 121 and 114 from each group. After 14 days of treatment, there was no difference with statistical significance between the two groups regarding SDRS total score change from baseline. FAS and PPS analysis showed that the brotizolam is non-inferior to estazolam in efficacy evaluation. There was also no difference with statistical significance regarding rebound rate between brotizolam and estazolam group in FAS. The rate of adverse event in two groups was with no statistically significant difference in SS. CONCLUSION: Brotizolam is effective and safe in relieving the symptoms of insomnia.

Effects of the dopamine D3 receptor (DRD3) gene polymorphisms on risperidone response: a pharmacogenetic study.

Previous observations of the anatomical distribution and pharmacological profile of the dopamine D(3) receptor (DRD3) have indicated its potential role in antipsychotic drug action. Risperidone, an effective first-line atypical antipsychotic agent, exhibits a relatively high affinity for this receptor. Recent studies have reported an association of the Ser9Gly polymorphism in the DRD3 gene with therapeutic response to risperidone, but the results were inconsistent. We therefore postulated that the Ser9Gly polymorphism might be in linkage disequilibrium with an undetected variant that exerts a direct influence on risperidone efficacy. The present study genotyped eight single nucleotide polymorphisms (SNPs) distributed throughout the DRD3 gene and examined five of these for association with treatment outcome, following an 8-week period of risperidone monotherapy in 130 schizophrenic patients from mainland China. Clinical symptoms were assessed before and after the treatment period, using the Brief Psychiatry Rating Scale (BPRS). The confounding effects of non-genetic factors were estimated and the baseline symptom score was included as a covariate for adjustment. Neither was any association observed between the five polymorphisms and improvement in total BPRS scores nor was any combined effect of these variants detected in the haplotype analysis. The current results indicate that genetic variations within the DRD3 gene may not contribute significantly to interindividual differences in the therapeutic efficacy of risperidone.

Lack of association between three serotonin genes and suicidal behavior in Chinese psychiatric patients.

BACKGROUND: Suicide is a significant health problem throughout the world. The serotoninergic system is believed to be involved in suicidal behavior and there is evidence of biological abnormalities of two serotonin receptors (HTR2A, HTR2C) and one serotonin transporter (5HTT) in suicide victims. Rs6313 (T102C) of HTR2A and rs6318 (Cys23Ser) of HTR2C have been investigated in suicide behavior in other studies. METHODS: Here, we investigated rs6313 and rs6318 and other 10 randomly chosen SNPs, of those three genes in a study of 329 psychiatric patients who had never attempted suicide and 297 patients who had attempted suicide. RESULTS: No associations were found for the 12 SNPS. CONCLUSIONS: Our results do not support the involvement of HTR2A, 5HTT or HTR2C in suicidal behavior in Han Chinese subjects.

Association study of a (TG)n dinucleotide repeat at chromosome 15q13.3 and schizophrenia in the Chinese population.

Linkage studies have suggested that chromosome 15q13-q14 may harbor a susceptibility locus for schizophrenia. In the current study, the association between a (TG)n dinucleotide repeat polymorphism at D15S976 and schizophrenia was investigated using two independent samples from the Han Chinese population. In a population-based study, no significant difference was found between the genotype and allele frequency distributions in schizophrenia patients and control subjects. In a family-based study, no significant transmission disequilibrium from heterozygous parents to affected offspring was observed. Further analysis of the parent-of-origin effect found nominally significant allele-wise transmission disequilibrium through maternal transmissions, while 157bp and 159bp alleles showed significant individual allelic transmission disequilibrium from heterozygous mothers to affected offspring. Our results did not support the hypothesis that the (TG)n dinucleotide repeat polymorphism plays a major role in schizophrenia susceptibility in the Chinese population. Further studies are needed to elucidate the putative parent-of-origin effect and its role in schizophrenia susceptibility.

A 6-week, multicenter, double-blind, double-dummy, chlorpromazine-controlled non-inferiorityrandomized phase iiitrial to evaluate the efficacy and safety of quetiapine fumarate (SEROQUEL) extended-release (XR) in the treatment of patients with schizophrenia and acute episodes.

This study aimed to evaluate the efficacy and safety of quetiapine fumarate extended-release (XR) in the treatment of Chinese patients with acute schizophrenia. Multicenter, double-blind, double-dummy, active-controlled non-inferiority randomized study in Chinese patients (n = 388) with schizophrenia randomly assigned to quetiapine XR or chlorpromazine for 6 weeks. Primary outcome was the change from baseline in Positive and Negative Syndrome Scale (PANSS) total score at the end of treatment. Safety objectives included adverse event (AE) monitoring, laboratory test results, and electrocardiograms. Changes in PANSS total score were -33.4 for quetiapine XR and -35.9 for chlorpromazine (P > 0.05). Least squares mean changes were: positive subscale, -9.9 ± 0.53 and -11.1 ± 0.51; negative subscale, -5.9 ± 0.50 and -6.7 ± 0.48; general psychopathology subscale, -12.9 ± 0.74 and -13.9 ± 0.71; aggression and hostility cluster scores, -4.8 ± 0.33 and -5.4 ± 0.32; and depression cluster scores, -1.8 ± 0.18 and -1.7 ± 0.18, for quetiapine XR and chlorpromazine, respectively. For quetiapine XR, AEs were constipation, dizziness, insomnia, and agitation, and nine patients (4.6%) discontinued due to AEs. For chlorpromazine, AEs were extrapyramidal symptoms, constipation, insomnia, dizziness, and agitation, and 17 patients (8.9%) discontinued due to AEs; two patients reported serious AEs. Quetiapine XR monotherapy was not inferior to chlorpromazine for treating acute schizophrenia in Chinese patients and was well tolerated.

Systematic study of association of four GABAergic genes: glutamic acid decarboxylase 1 gene, glutamic acid decarboxylase 2 gene, GABA(B) receptor 1 gene and GABA(A) receptor subunit beta2 gene, with schizophrenia using a universal DNA microarray.

Several studies have suggested the dysfunction of the GABAergic system as a risk factor in the pathogenesis of schizophrenia. In the present study, case-control association analysis was conducted in four GABAergic genes: two glutamic acid decarboxylase genes (GAD1 and GAD2), a GABA(A) receptor subunit beta2 gene (GABRB2) and a GABA(B) receptor 1 gene (GABBR1). Using a universal DNA microarray procedure we genotyped a total of 20 SNPs on the above four genes in a study involving 292 patients and 286 controls of Chinese descent. Statistically significant differences were observed in the allelic frequencies of the rs187269C/T polymorphism in the GABRB2 gene (P=0.0450, chi(2)=12.40, OR=1.65) and the -292A/C polymorphism in the GAD1 gene (P=0.0450, chi(2)=14.64 OR=1.77). In addition, using an electrophoretic mobility shift assay (EMSA), we discovered differences in the U251 nuclear protein binding to oligonucleotides representing the -292 SNP on the GAD1 gene, which suggests that the -292C allele has reduced transcription factor binding efficiency compared with the 292A allele. Using the multifactor-dimensionality reduction method (MDR), we found that the interactions among the rs187269C/T polymorphism in the GABRB2 gene, the -243A/G polymorphism in the GAD2 gene and the 27379C/T and 661C/T polymorphisms in the GAD1 gene revealed a significant association with schizophrenia (P<0.001). These findings suggest that the GABRB2 and GAD1 genes alone and the combined effects of the polymorphisms in the four GABAergic system genes may confer susceptibility to the development of schizophrenia in the Chinese population.

The DNA methylation profile within the 5'-regulatory region of DRD2 in discordant sib pairs with schizophrenia.

Studies of discordance in monozygotic twins have demonstrated that environmental effects play an important role in the pathogenesis of schizophrenia. DNA microarray analysis has revealed upregulation of the DRD2 gene in peripheral blood lymphocytes of schizophrenic patients. We hypothesized that this expression alteration could involve the DNA (CpG) methylation status that is implicated to the transcription status of the gene and in this study we used bisulfited sequence analysis to determine the DNA methylation status of a typical CpGs island within the 5'-regulatory region of DRD2 in peripheral blood lymphocytes from 48 discordant sib pairs suffering from schizophrenia. We found that the methylated cytosines occurred mainly in three clusters. No statistically significant difference in frequency of site-specific cytosine methylation modification of DRD2 between patients and normal controls was found nor did we find any significant association between sex, age on admission or age at onset of schizophrenia and methylated cytosines of DRD2. Our study did not support the hypothesis that site-specific cytosine methylation of DRD2 plays a role in the psychopathology of schizophrenia.

Response of risperidone treatment may be associated with polymorphisms of HTT gene in Chinese schizophrenia patients.

Serotonin transporter (5-HTT) is a key component of the serotonergic neurotransmitter system. Few studies have focused on polymorphisms of the serotonin transporter and antipsychotic response and, in particular, there have so far been no published studies on the association between the serotonin transporter and response to risperidone. This study examined the relationship between two polymorphisms of the serotonin transporter and the efficacy of risperidone treatment in 129 patients with schizophrenia. Our results revealed that patients with l allele of HTTRLP showed a greater improvement than those without l allele on the overall brief psychiatric rating scale (BPRS) (P=0.025). But no such relationship was found for the HTTVNTR. In haplotype analysis, the frequency of L-12 haplotype showed a significant difference between the responder group and the non-responder group (P=0.005). Our study has, for the first time, produced evidence that the potential for therapy in patients with schizophrenia is related to the HTTRLP polymorphism in the HTT gene and haplotype L-12 may help to predict risperidone treatment efficiency.

Serum prolactin levels, plasma risperidone levels, polymorphism of cytochrome P450 2D6 and clinical response in patients with schizophrenia.

The object of this study is to assess 1) the relationship between plasma antipsychotic drug concentration, serum prolactin levels and the clinical efficacy of risperidone, 2) the relationship between the CYP2D6 polymorphisms and metabolizing of risperidone and 3) the role of 9-hydroxyrisperidone in elevating prolactin levels. One-hundred and eighteen Chinese schizophrenia patients (40 males, 78 females, age 15-60 years) were given risperidone at dosages ranging from 2-8 mg/day for 8 weeks. Clinical efficacy was determined using the Brief Psychiatric Rating Scores (BPRS). Serum prolactin levels were assayed before and after the 8 week treatment and plasma risperidone and 9-hydroxyrisperidone levels were also measured at the end of the 8-week treatment. The results showed there was no significant correlation between the concentration of active moiety and clinical response. Risperidone treatment significantly increased serum prolactin levels. Furthermore, changes of prolactin levels were not correlated with the clinical response. For the risperidone/ 9-hydroxyrisperidone ratio, there was a statistically significant difference among the CYP2D6*1/*1, *1/*10, *10/*10 genotypes (Kruskal-Wallis test, p = 0.012). No significant differences were found in the concentration of 9-hydroxyrisperidone and active moiety among the genotypes. In addition, the concentration of 9-hydroxyrisperidone was not significantly correlated with the increase of serum prolactin. In conclusion, our study has, for the first time, produced evidence that in Chinese schizophrenic patients, the metabolism of risperidone is dependent on CYP2D6. Neither changes in serum prolactin levels nor plasma concentration of active moiety were significantly correlated with clinical efficacy of risperidone. 9-hydroxyrisperidone may not play a predominant role in elevating serum prolactin level.

[Association study of an (AC)n dinucleotide repeat and schizophrenia in Asian and European populations].

Linkage studies have suggested that chromosome 15q13-q14 may harbor a susceptibility locus for schizophrenia. In the current study, the association between a (AC)n dinucleotide repeat polymorphism at D15S118 and schizophrenia was investigated using three independent samples from the Han Chinese population and the Scotland population. In the population-based study, a significant difference was found between the allele frequency distributions in schizophrenia patients and control subjects in the Scottish samples (P = 0.04), but was not replicated in the Chinese samples. In a family-based study, no significant transmission disequilibrium from heterozygous parents to affected offspring was observed. Overall, our results did not support the hypothesis that the (AC)n dinucleotide repeat polymorphism plays a major role in schizophrenia susceptibility, at least in the Chinese population. Further studies are needed to elucidate its role in schizophrenia susceptibility in European population.

Population-based and family-based association studies of an (AC)n dinucleotide repeat in alpha-7 nicotinic receptor subunit gene and schizophrenia.

The human alpha-7 neuronal nicotinic receptor subunit (CHRNA7) gene, located at chromosome 15q13.2, represents a strong candidate gene for schizophrenia. We have examined an (AC)n dinucleotide repeat in intron 2 of the CHRNA7 gene, which was previously shown to be strongly linked with schizophrenia, using both population-based and family-based association studies. In the population-based study, no significant differences between the genotype and allele frequency distributions in schizophrenia patients and control subjects were observed after correction for multiple testing, although a nominally significant association between the most common allele and schizophrenia was observed (P = 0.023, uncorrected for multiple testing). In the family-based study, there is no significant over-transmission (Transmitted/Non-transmitted: 61/50) of the same allele in 160 family trios. Overall, our results do not support a major role for the (AC)n dinucleotide repeat in schizophrenia susceptibility in Han Chinese. Further large-scale genetic studies based on a set of single nucleotide polymorphisms (SNPs) that fully characterize the linkage disequilibrium patterns at the CHRNA7 gene are necessary to determine the relevance of this gene as a risk factor for schizophrenia susceptibility.

A family-based association study of kinesin heavy chain member 2 gene (KIF2) and schizophrenia.

Schizophrenia is a multifactorial disease characterized by multiple genetic susceptibility elements. The human KIF2 gene represents an orthologue of the murine Kif2a, which plays an important role in the transport of various membranous organelles and protein complexes on microtubules. To examine whether this gene is involved in schizophrenia etiology, we undertook studies of transmission disequilibrium in a cohort of affected family samples to test for association. Although, we failed to detect any positive results in single markers, a common two-SNP haplotype (rs2289883/rs464058, G/A) showed a significant association with the disease and a four-SNP haplotype (T/G/A/G) with a frequency of 23.4% was identified in parental chromosomes and showed a significant association with the disease (P=0.00795). Our results demonstrate that the KIF2 gene, located at 5q12.1, is a potential schizophrenia susceptibility gene.

Efficacy and safety of quetiapine extended release monotherapy in bipolar depression: a multi-center, randomized, double-blind, placebo-controlled trial.

RATIONALE: Quetiapine extended release (XR) has been used to treat various psychiatric disorders, including depressive episodes associated with bipolar I and II disorders. Quetiapine XR is the first approved drug in China for the treatment of bipolar disorder. OBJECTIVES: The study evaluated the efficacy and safety of short-term quetiapine XR monotherapy in the treatment of depressive episodes of bipolar I and II disorders. METHODS: This was an 8-week multi-center, randomized, double-blind, placebo-controlled, fixed-dose phase 3 study. The primary endpoint was the mean change of the Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Secondary endpoints included Clinical Global Impressions-Bipolar (CGI-BP) and remission rates. RESULTS: The study recruited 279 adult bipolar I or II patients currently experiencing depression from 11 Chinese provinces. Of these, 139 received quetiapine XR (300 mg/day) and 140 received placebo for 8 weeks. The mean change in the MADRS total score was significantly greater in the quetiapine XR group than in the placebo group (-19.00 ± 7.88 vs. -16.20 ± 9.32; p = 0.004). Adverse events occurred in 96 patients (65.3 %) in the quetiapine XR group and 72 (49.0 %) in the placebo group. The incidence of serious adverse events did not differ significantly between the groups (p = 0.247). CONCLUSIONS: This study, which is the first to evaluate 300 mg/day quetiapine XR monotherapy for depression in Chinese patients with bipolar disorders, found that this drug was superior to the placebo. Quetiapine XR was generally safe and well tolerated (ClinicalTrials.gov number, NCT01256177).

Catechol-O-methyltransferase gene Val/Met functional polymorphism and risk of schizophrenia: a large-scale association study plus meta-analysis.

BACKGROUND: A common functional polymorphism (Val/Met) in the catechol-O-methyltransferase gene (COMT) that markedly affects enzyme activity has been shown to affect executive cognition and the physiology of the prefrontal cortex in humans. It is hypothesized that the high activity Val allele slightly increases risk for schizophrenia through its effect on dopamine-mediated prefrontal information processing. METHODS: We compared the allele/genotype frequencies of the Val/Met polymorphism in a large independent patient-control sample (862 patient and 928 healthy control subjects) from Han Chinese population, and an update meta-analysis was performed to assess the collective evidence across individual studies. RESULTS: No statistically significant differences were found in allele or genotype frequencies between patient and normal control subjects, although a nonsignificant overrepresentation of the Val allele in schizophrenia patients (odds ratio [OR] = 1.09, 95% confidence interval [CI] = .94-1.26) was suggested. Comparatively, the meta-analysis of all published population-based association studies showed statistically significant evidence for heterogeneity among the group of studies. Stratification of the studies by ethnicity of the samples yielded no significant evidence for an association with the Val allele in Asian population (OR = .96, 95% CI = .85-1.09), nor in European population (OR = 1.06, 95% CI = .95-1.19). CONCLUSIONS: Our data provide minimal evidence that the Val allele is a susceptibility factor for schizophrenia in either European or Asian populations.

A family-based study of the association between the G72/G30 genes and schizophrenia in the Chinese population.

Studies have shown a strong positive association between schizophrenia and G72/G30, demonstrated by both individual markers and haplotypes. A further functional study also supports the role of G72 in the etiology of schizophrenia. In this study, we have replicated these results of transmission/disequilibrium testing (TDT) and haplotype analysis in the Han Chinese population, showing P values of 0.0018 and 0.00007 for individual markers and haplotypes, respectively. Hence, our data supports the hypothesis that G72/G30 are important candidate genes for explaining schizophrenia in the Han Chinese population.

A family-based association study of the MOG gene with schizophrenia in the Chinese population.

Recently the expression of human myelin/oligodendrocyte glycoprotein (MOG) has been found to be significantly downregulated in the brain tissue of subjects with schizophrenia, suggesting that the MOG gene resides within a high-susceptibility locus for schizophrenia. In order to test this prediction, we analyzed three microsatellites from MOG in the Han Chinese population using a sample of 532 trios. Analysis of allele, genotype and haplotype frequencies showed weak positive association between the markers and the disease (p=0.01982). Our results would indicate that the MOG gene may play a significant role in schizophrenia in the Han Chinese. However, further study is required using other methods and involving other populations.

Response to chlorpromazine treatment may be associated with polymorphisms of the DRD2 gene in Chinese schizophrenic patients.

Previous studies have demonstrated that the -141C Ins/Del and TaqI A polymorphisms in the DRD2 gene affect the density of the dopamine D2 receptor. The present study examines the correlation between these two polymorphisms and the therapeutic response to chlorpromazine, a typical antipsychotic drug, in 135 inpatients with schizophrenia. Clinical symptoms were evaluated using the Brief Psychiatry Rating Scale (BPRS) before and after 8 weeks of treatment with 300-600 mg/day of chlorpromazine. Our results show that genotyping -141C Ins/Del may help to predict the efficacy of chlorpromazine treatment (P=0.01) due to the fact that patients with no Del allele showed greater improvement than those with Del allele on the overall BPRS (P=0.03), and that, therefore, the potential for therapy in patients with schizophrenia is related to the -141C Ins/Del polymorphism in the DRD2 gene. However, no such relationship was found for the TaqI A polymorphism.

Polymorphisms of myelin-associated glycoprotein gene are associated with schizophrenia in the Chinese Han population.

Results of gene expression microarray and quantitative PCR studies have suggested abnormalities in the expression of myelin-related genes including myelin-associated glycoprotein (MAG) in schizophrenic patients. Research provides strong evidence for oligodendrocyte dysfunction in schizophrenics. In order to further assess the role of MAG in schizophrenia, we examined four single nucleotide polymorphisms (SNPs), namely rs2301600, rs3746248, rs720309 and rs720308, of this gene in Chinese schizophrenic patients (n=470) and healthy controls (n=470). The distribution of rs720309 T/A genotypes showed a strong association with schizophrenia (chi(2)=14.58, d.f.=2, P=0.0008). A haplotype constructed of rs720309-rs720308 also revealed a significant association with schizophrenia (chi(2)=11.914, d.f.=3, P=0.0084). Our findings of a significant associations between schizophrenia and the MAG gene suggest that this gene may be involved in susceptibility to schizophrenia in the Chinese Han population.

A family-based association study of PLP1 and schizophrenia.

Recently, proteolipid protein 1 (PLP1) has been identified as downregulated in schizophrenia by quantitative PCR and other technologies. In this work we attempted to investigate the role of PLP1 in the etiology of schizophrenia using a family based association study in 487 Chinese Han family trios. The TDT for allelic association demonstrated that, in male, a weak association was detected in SNP rs475827 with p=0.0294, suggesting that the genetic polymorphisms within PLP1 in male are likely to confer an increased susceptibility to schizophrenia in the Chinese population.

No association between the serotonin 1B receptor gene and schizophrenia in a case-control and family-based association study.

Previous studies have demonstrated that polymorphisms in the putative promoter region of the human serotonin receptor 1B (HTR1B) gene affect gene expression [H.F. Sun, Y.T. Chang, C.S. Fann, C.J. Chang, Y.H. Chen, Y.P. Hsu, W.Y. Yu, A.T. Cheng, Association study of novel human serotonin 5-HT(1B) polymorphisms with alcohol dependence in Taiwanese Han, Biol. Psychiatry 51 (2002) 896-901; J. Duan, A.R. Sanders, J.E. Molen, L. Martinolich, B.J. Mowry, D.F. Levinson, R.R. Crowe, J.M. Silverman, P.V. Gejman, Polymorphisms in the 5'-untranslated region of the human serotonin receptor 1B (HTR1B) gene affect gene expression, Mol. Psychiatry 8 (2003) 901-910]. And the silent mutation G861C allele has been reported to be associated with several psychiatric disorders. Thus, we performed a case-control association study (456 cases and 557 controls) of the five variants in HTR1B gene (T-261G, -182INS/DEL-181, A-161T, C129T and G861C) with schizophrenia. The results showed that neither the allelic distribution nor the major haplotype distribution (except for a rare haplotype) of five SNPs in patients was significantly different from that in controls. A further family-based association study (229 family trios) of G861C allele suggested that HTR1B was not a susceptible gene with schizophrenia in our sample. In conclusion, these data do not support the idea that HTR1B gene plays a major role in the etiopathogenesis of schizophrenia in Chinese Han population.