Epigenetics for Drug Discovery: Dissecting the Effect of High Antipsychotic Dosage and D2 Blockage on Peripheral DNA Methylation.

INTRODUCTION: The relationship between genetic polymorphisms of antipsychotic drug-metabolizing agents and drug receptors has been often investigated. DNA methylation is a form of epigenetic modification that regulates gene expression. Few studies have analyzed the relationship between genome-wide methylation patterns and antipsychotic dosage. The primary aim of this pilot study was to investigate the association between antipsychotic dosage and genome-wide DNA methylation in patients with schizophrenia (SCZ). METHODS: Current dosage of antipsychotic medications was assessed in 136 patients with SCZ. Dosage was standardized using three different methods: chlorpromazine equivalent dose (CPZe), defined daily dose (DDD), and percentage of Lexicomp maximum dose (PM%). DNA methylation was measured in white blood cells. Antipsychotic dosage was the primary outcome variable in a model, including genome-wide methylation status as the main predictor. RESULTS: This study did not show any association between DNA methylation and dosage variation for CPZe, PM%, and DDD. However, the probe cg271403389 was consistently associated with antipsychotic dosage across the three standardization methods. When looking at the genomic location of the most significant probes, we found that 15% were intergenic, 23% were in the distal promoter, 9% in the 3'untranslated region, 32% in the gene body, 3% in the 5' untranslated region, 15% in the proximal promoter, and 3% in the first exon. DISCUSSION: This study shows the importance of investigating the relationship between DNA methylation and optimal antipsychotic dosage to personalize treatment in SCZ. Future studies require larger prescription databases to build on the results of this analysis.

Novel intranasal treatment for anxiety disorders using amiloride, an acid-sensing ion channel antagonist: Pharmacokinetic modeling and simulation.

OBJECTIVE: To develop a physiologically based pharmacokinetic (PBPK) model for amiloride, an acid-sensing ion channel (ASIC) antagonist, and to simulate its pharmacokinetics in plasma and the central nervous system following intranasal administration in a virtual human population. MATERIALS AND METHODS: We first developed a PBPK model of amiloride after oral administration and optimized the model using data from five clinical studies. Next, we added a nasal compartment to the amiloride oral PBPK model and parameterized using data from previous clinical studies. We simulated amiloride's pharmacokinetics in plasma, brain, and cerebrospinal fluid (CSF) after intranasal administration of amiloride at various doses in a virtual human population. RESULTS: The target amiloride concentration in the central nervous system required for maximal ASIC inhibition was achieved with a 75-mg intranasal amiloride dose. However, this finding is based on simulations performed using a mathematical model and needs to be further validated with appropriate clinical data. CONCLUSION: The nasal PBPK model of amiloride could be used to design future clinical studies and allow for successful clinical translation of intranasal amiloride formulation.

"This Is ME": Promoting Person-Centred Care within the Digital Health Environment.

In this paper, we describe the implementation of an initiative called "This Is ME," which involves a change in the summary page of a patient's electronic health record in order to include their story and provide a more humanistic perspective. The change includes information related to their family, hobbies and interests - a change that has important implications for facilitating conversation and relationship-building between providers and patients. Since implementation, 1,246 (and counting) patient stories were shared with over 300 healthcare providers, including nurses, social workers, physicians and others. We also share the results of our evaluation of the initiative and provide recommendations for organizations embarking on similar initiatives.

Genome-wide methylation association with current suicidal ideation in schizophrenia.

In this study, we investigate the epigenetic mechanisms associated with current suicidal ideation. Gene expression changes have been found in post-mortem brain of suicide victims. However, it is not clear how in-vivo gene expression change confers risk for suicide. DNA methylation is a form of epigenetic modification that regulates gene expression. Our primary aim is to investigate genome-wide methylation in conferring risk for current suicidal ideation (SI) in schizophrenia. The presence of current SI and genome-wide methylation patterns were assessed in 107 patients with schizophrenia. DNA methylation has been measured in white blood cells as a possible peripheral biomarker of SI. SI was the primary outcome variable in a model including methylation status of white blood cells using the Illumina 450 array. We have tested the association with genome-wide methylation levels in 19 subjects with current SI and 88 subjects without current SI and we found that higher methylation level in the CpG cg06121808 located in the gene SLC20A1 on chromosome 2 was associated with current SI (p = 0.000003; beta difference = 0.06). Furthermore, the distal promoter analysis showed that the gene SMPD2 was hypermethylated in suicide ideators (p = 0.0001; beta difference = 0.02). Thus, molecular biomarkers could advance our understanding of the molecular mechanisms of stress-related SI. Furthermore, the methylation sites that we have identified should be replicated in other suicide related phenotypes to generate robust biomarkers with high translational value for proof of concept interventions aiming at reducing SI.

Venous Blood-Based Biomarkers in the China Health and Retirement Longitudinal Study: Rationale, Design, and Results From the 2015 Wave.

Blood biomarkers provide critical information about the health of older populations, especially in large developing countries where self-reports of health are often inaccurate due to lack of access to health care. However, it is very difficult to collect blood samples in representative population surveys in such countries. The China Health and Retirement Longitudinal Study (CHARLS), a nationally representative study of middle-aged and older Chinese, represents one of the first efforts to include blood biomarkers in a nationally representative survey of China. In the 2015 wave of CHARLS, 13,013 respondents located in 150 counties around China donated whole blood, which was assayed on a range of indicators. Here we describe the process of the sample collection, transportation, storage, and analysis and present basic statistics.

Validation of neuropsychological tests for the China Health and Retirement Longitudinal Study Harmonized Cognitive Assessment Protocol.

OBJECTIVE: To compare and validate neurocognitive tests in the Harmonized Cognitive Assessment Protocol (HCAP) for the China Health and Retirement Longitudinal Study (CHARLS), and to identify appropriate tests to be administered in future waves of CHARLS. METHODS: We recruited 825 individuals from the CHARLS sample and 766 subjects from hospitals in six provinces and cities in China. All participants were administered the HCAP-neurocognitive tests, and their informants were interviewed regarding the respondents' functional status. Trained clinicians administered the Clinical Dementia Rating scale (CDR) to assess the respondents' cognitive status independently. RESULTS: The testing protocol took an average of 58 minutes to complete. Refusal rates for tests of general cognition, episodic memory, and language were less than 10%. All neurocognitive test scores significantly correlated with the CDR global score (correlation coefficients ranged from 0.139 to 0.641). The Mini-Mental State Examination (MMSE), the Health and Retirement Study (HRS) - telephone interview for cognitive status (TICS), community screening instrument for dementia (CSI-D) for respondent, episodic memory and language tests each accounted for more than 20% of the variance in global CDR score (p < 0.001) in bivariate tests. In the CHARLS subsample, age and education were associated with neuropsychological performance across most cognitive domains, and with functional status. CONCLUSION: A brief set of the CHARLS-HCAP neurocognitive tests are feasible and valid to be used in the CHARLS sample and hospital samples. It could be applied in the future waves of the CHARLS study, and it allows estimating the prevalence of dementia in China through the population-based CHARLS.

Investigation of correlations between DNA methylation, suicidal behavior and aging.

OBJECTIVES: Suicidal behavior (SB) is a major cause of mortality for patients diagnosed with bipolar disorder (BD). In this study, we investigated epigenetic differences in BD participants with and without a history of SB. METHODS: We used suicidality scores constructed from Schedule for Clinical Assessments in Neuropsychiatry (SCAN) interview questions about suicidal thought and behavior to identify individuals from a BD cohort of n=452; participants with the most extreme high (H-SB, n=18) and most extreme low (L-SB, n=22) scores were used as cases and controls, respectively. Epigenome-wide DNA methylation patterns were compared between the two groups using the Illumina Infinium Human Methylation 450 BeadChip microarray. DNA methylation age was compared to chronological tissue age. RESULTS: We observed highly significant differences in methylation between cases and controls in three genomic regions enriched for epigenetic modifications corresponding to gene regulatory regions. BD participants with a history of SB showed less overall methylation in the 5' untranslated region of Membrane palmitoylated protein 4 (MPP4) (P=7.42×10-7 ) and in intron 3 of TRE2/BUB2/CDC16 domain family member 16 (TBC1D16) (P=6.47×10-7 ), while exon 1 of Nucleoporin 133 (NUP133) was less methylated in controls (P=1.17x10-6 ). Moreover, we observed a greater correlation between DNA methylation age and tissue age in controls (r=.91, P<.0001) than in the H-SB group (r=.83, P<.0001). CONCLUSIONS: We report significant findings at three loci based on a methylome scan of participants with BD for an SB phenotype, and potentially altered molecular aging in suicide attempters. Despite the small sample size, our proof-of-concept study highlights the potential for epigenetic factors to be useful in understanding the molecular underpinnings of suicide with the ultimate aim of its prevention.

Health Insurance and Health Care among the Mid-Aged and Older Chinese: Evidence from the National Baseline Survey of CHARLS.

We document the recent profile of health insurance and health care among mid-aged and older Chinese using data from the China Health and Retirement Longitudinal Study conducted in 2011. Overall health insurance coverage is about 93%. Multivariate regressions show that respondents with lower income as measured by per capita expenditure have a lower chance of being insured, as do the less-educated, older, and divorced/widowed women and rural-registered people. Premiums and reimbursement rates of health insurance vary significantly by schemes. Inpatient reimbursement rates for urban people increase with total cost to a plateau of 60%; rural people receive much less. Demographic characteristics such as age, education, marriage status, per capita expenditure, and self-reported health status are not significantly associated with share of out-of-pocket cost after controlling community effects. For health service use, we find large gaps that vary across health insurance plans, especially for inpatient service. People with access to urban health insurance plans are more likely to use health services. In general, Chinese people have easy access to median low-level medical facilities. It is also not difficult to access general hospitals or specialized hospitals, but there exists better access to healthcare facilities in urban areas. Copyright © 2016 John Wiley & Sons, Ltd.

Genome-wide association analysis to predict optimal antipsychotic dosage in schizophrenia: a pilot study.

In recent years, several studies have investigated genetic polymorphisms of antipsychotic drug-metabolizing enzymes and receptors. However, most studies focused on drug response and very few have investigated the genetic influence on antipsychotic dosage. The aim of the present study is to test the association between antipsychotic dosages at genome-wide level. The current dosage of antipsychotic medications was collected from 79 schizophrenia patients. The dosage was standardized using three different methods: chlorpromazine equivalent (CPZe), defined daily dose (DDD), and percentage of maximum dose (PM %). The patients were then genotyped using the Illumina HumanOmni2.5-8 BeadChip Kit. All markers were screened for significance using linear regression, and the p values were visualized using a Manhattan plot. The genome-wide analysis showed that the top Single-Nucleotide Polymorphisms (SNPs) associated with dosage variation were rs981975 on chromosome 14 for CPZe, rs4470690 on chromosome 4 for PM %, and rs79323383 on chromosome 8 for DDD. However, no genome-wide significantly associated SNPs were identified. In this pilot sample, we found promising trends for pharmacodynamic targets associated with antipsychotic dosage. Therefore, studies combining large prescription databases may identify genetic predictors to adjust the dose of antipsychotic medication.

Interaction between Methylation and CpG Single-Nucleotide Polymorphisms in the HTR2A Gene: Association Analysis with Suicide Attempt in Schizophrenia.

Dysfunctional mechanisms in the serotonergic system have been implicated in suicidal behavior among patients with schizophrenia. However, previous association analyses of major serotonin genes have provided inconsistent findings regarding their role in suicidal behavior. The goal of the current study was to identify single-nucleotide polymorphisms (SNP) within HTR2A that directly affect CpG methylation sites in schizophrenic patients with suicidal behavior. Furthermore, direct methylation analysis was performed using genomic DNA from peripheral leukocytes employing bisulfite pyrosequencing to assess the contributions of six CpG sites in HTR2A exon I in 67 schizophrenia patients assessed for lifetime suicide attempt. Potential methylation in 25 CpG SNPs across the entire HTR2A gene was analyzed considering their direct contribution to methylation. When we compared direct methylation between attempters and nonattempters, we found that only the polymorphic T102C (rs6313) was significantly different between the two groups (p = 0.02). Furthermore, in the potential methylation analysis, we found a nominal association with suicide attempt for six of the 25 SNPs analyzed, i.e. rs2770293 (p = 0.045), rs6313 (p = 0.033), rs17068986 (p = 0.029), rs4942578 (p = 0.024), rs1728872 (p = 0.014), and rs9534511 (p = 0.003). The results of this investigation provide preliminary evidence that the combined analysis of CpG SNPs and methylation may be useful for investigating the genetic and epigenetic factors involved in suicidal behavior.

Differential Allelic Expression of HTR1B in Suicide Victims: Genetic and Epigenetic Effect of the Cis-Acting Variants.

OBJECTIVES: In the present study, we tested the allelic imbalance of the C861G single nucleotide polymorphism (SNP) of HTR1B in the frontal cortex of suicide victims. METHODS: The study was conducted using 3 sets of samples. First, C861G allele-specific mRNA levels in the frontal cortex were compared between suicide (n = 13) and nonsuicide controls (n = 13) from the Stanley Medical Research postmortem brain collection. Second, we tested common variants in the HTR1B promoter for linkage disequilibrium (LD) with the C861G variant in an unrelated sample of suicide attempters (SA; n = 38) and non-SA (NSA; n = 42). Finally, we performed a family-based association study of the C861G and promoter variants in 162 nuclear families using suicidal behavior severity scores as phenotype. RESULTS: We observed no alterations in the C/G expression ratio in suicide victims compared to nonsuicide controls (p = 0.370). When comparing the LD between the C861G and cis-acting SNPs, we did not find any differences in SA and NSA. There was no association between preferential transmission of cis-acting SNPs and suicidal behavior severity scores in both maternal and paternal meiosis. CONCLUSIONS: We found several promoter variants in LD that may potentially influence the allelic imbalance in the C861G variant. However, no evidence of allelic imbalance nor parent-of-origin effects of the C861G variant was observed in suicidal behavior. Further research is required to assess this marker in larger cohorts.

Genome-wide association study of bipolar disorder in Canadian and UK populations corroborates disease loci including SYNE1 and CSMD1.

BACKGROUND: Recently, genome-wide association studies (GWAS) for cases versus controls using single nucleotide polymorphism microarray data have shown promising findings for complex neuropsychiatric disorders, including bipolar disorder (BD). METHODS: Here we describe a comprehensive genome-wide study of bipolar disorder (BD), cross-referencing analysis from a family-based study of 229 small families with association analysis from over 950 cases and 950 ethnicity-matched controls from the UK and Canada. Further, loci identified in these analyses were supported by pathways identified through pathway analysis on the samples. RESULTS: Although no genome-wide significant markers were identified, the combined GWAS findings have pointed to several genes of interest that support GWAS findings for BD from other groups or consortia, such as at SYNE1 on 6q25, PPP2R2C on 4p16.1, ZNF659 on 3p24.3, CNTNAP5 (2q14.3), and CDH13 (16q23.3). This apparent corroboration across multiple sites gives much confidence to the likelihood of genetic involvement in BD at these loci. In particular, our two-stage strategy found association in both our combined case/control analysis and the family-based analysis on 1q21.2 (closest gene: sphingosine-1-phosphate receptor 1 gene, S1PR1) and on 1q24.1 near the gene TMCO1, and at CSMD1 on 8p23.2, supporting several previous GWAS reports for BD and for schizophrenia. Pathway analysis suggests association of pathways involved in calcium signalling, neuropathic pain signalling, CREB signalling in neurons, glutamate receptor signalling and axonal guidance signalling. CONCLUSIONS: The findings presented here show support for a number of genes previously implicated genes in the etiology of BD, including CSMD1 and SYNE1, as well as evidence for previously unreported genes such as the brain-expressed genes ADCY2, NCALD, WDR60, SCN7A and SPAG16.

Association study of GABRG2 polymorphisms with suicidal behaviour in schizophrenia patients with alcohol use disorder.

BACKGROUND: Schizophrenia is a severe neuropsychiatric disorder where the role of γ-aminobutyric acid (GABA), an inhibitory neurotransmitter, has been implicated in its aetiopathophysiology. Several genes coding for GABAA subunits, including the GABRG2 gene that encodes the γ2 subunit, are clustered at 5q31-q35, a chromosomal region that is associated with schizophrenia in genome scan studies. We recently reported GABRG2 to be associated with schizophrenia in our case-control and family samples. METHODS: We tested eight single-nucleotide polymorphisms spanning the GABRG2 gene for an association with suicidal behaviour in our schizophrenia sample of European ancestry (n = 197), taking into account history of alcohol abuse or dependence. RESULTS: We found the haplotypes of the rs183294 and rs209356 markers to be significantly associated with history of suicide attempt (p < 0.01) as well as suicide specifier scores (p < 0.05). The association appeared to be originating in patients with a history of alcohol dependence or abuse. CONCLUSIONS: Taken together, the results of the present study suggest that GABRG2 may be involved in suicidal behaviour in schizophrenia patients with alcohol dependence or abuse, but replications are required. These results may help in the discovery of novel treatments for alcoholism and/or prevention of suicide.

Copy number variant study of bipolar disorder in Canadian and UK populations implicates synaptic genes.

Genome-wide single nucleotide polymorphism (SNP) data from 936 bipolar disorder (BD) individuals and 940 psychiatrically healthy comparison individuals of North European descent were analyzed for copy number variation (CNV). Using multiple CNV calling algorithms, and validating using in vitro molecular analyses, we identified CNVs implicating several candidate genes that encode synaptic proteins, such as DLG1, DLG2, DPP6, NRXN1, NRXN2, NRXN3, SHANK2, and EPHA5, as well as the neuronal splicing regulator RBFOX1 (A2BP1), and neuronal cell adhesion molecule CHL1. We have also identified recurrent CNVs on 15q13.3 and 16p11.2-regions previously reported as risk loci for neuropsychiatric disorders. In addition, we performed CNV analysis of individuals from 215 BD trios and identified de novo CNVs involving the NRXN1 and DRD5 genes. Our study provides further evidence of the occasional involvement of genomic mutations in the etiology of BD, however, there is no evidence of an increased burden of CNVs in BD. Further, the identification of CNVs at multiple members of the neurexin gene family in BD individuals, supports the role of synaptic disruption in the etiology of BD.

Association and CpG SNP analysis of HTR4 polymorphisms with suicidal behavior in subjects with schizophrenia.

Suicide is a major contributor to the morbidity and mortality rates in schizophrenia. Genetic and epigenetic factors have been reported to modulate the risk for suicide although the precise mechanism and magnitude of these contributions is unknown. Previous research indicates that suicide attempters present abnormalities in the serotonergic system. The present study aimed to identify genetic and epigenetic risk variants of the serotonin 5-HT4 receptor gene (HTR4) for suicidal behavior. We included 234 subjects diagnosed with schizophrenia. For this purpose, we analyzed 11 markers across HTR4 and performed genotype, haplotype and potential methylation analyses, correcting for clinical covariates and ethnic stratification. Three blocks were revealed from the LD analysis. Haplotypes in Block 3 were significantly associated with suicide attempt. The potential methylation analysis was not significant. Our results suggest that HTR4 polymorphisms may not play a major role in the susceptibility for suicidal behavior in subjects with schizophrenia. Moreover, although not significant, the CpG SNP potential methylation analysis would be informative for future methylation analysis on this gene.

Commercialization of quality.

Without overriding financial imperatives, the commercial marketplace for products and services enabling quality improvement, quality assurance, and quality control has been limited in health care. Companies serving this industry have had a difficult time finding business justification to bring these products to market. However, government initiatives in the past 6 years attempting to reduce health care costs are placing an emphasis on better, more appropriate, and more effective health care delivery through evidence-based medicine. Incentives,penalties, and reimbursements for providers serving Medicare and Medicaid patients are being implemented or altered to encourage this adoption. Within this new environment,quality systems become vital tools in managing optimal operations, and thus, a new commercial marketplace is rapidly evolving for vendors to develop, promote, and profitably sell quality assurance and quality control products and services.With a viable, growing, and competitive market, radiologists, technologists, and radiology administrators may look forward to having a wide choice of quality tools to help them make their departments an invaluable resource in a changing healthcare delivery system.

Characterization of multidrug resistance 1a/P-glycoprotein knockout rats generated by zinc finger nucleases.

The development of zinc finger nuclease (ZFN) technology has enabled the genetic engineering of the rat genome. The ability to manipulate the rat genome has great promise to augment the utility of rats for biological and pharmacological studies. A Wistar Hannover rat model lacking the multidrug resistance protein Mdr1a P-glycoprotein (P-gp) was generated using a rat Mdr1a-specific ZFN. Mdr1a was completely absent in tissues, including brain and small intestine, of the knockout rat. Pharmacokinetic studies with the Mdr1a P-gp substrates loperamide, indinavir, and talinolol indicated that Mdr1a was functionally inactive in the blood-brain barrier and intestine in Mdr1a(-/-) rats. To identify possible compensatory mechanisms in Mdr1a(-/-) rats, the expression levels of drug-metabolizing enzyme and transporter-related genes were compared in brain, liver, kidney, and intestine of male and female Mdr1a(-/-) and control rats. In general, alterations in gene expression of these genes in Mdr1a(-/-) rats seemed to be modest, with more changes in female than in male rats. Taken together, our studies demonstrate that the ZFN-generated Mdr1a(-/-) rat will be a valuable tool for central nervous system drug target validation and determining the role of P-gp in drug absorption and disposition.

Analysis of treatment-resistant schizophrenia and 384 markers from candidate genes.

The treatment of patients with schizophrenia who fail to respond to antipsychotics is a major challenge and the proportion of treatment-resistant patients is estimated to be 20 to 40%. There are few genetic association studies that have compared resistant versus non-resistant schizophrenic patients; however, many genetic association studies focusing on antipsychotic response have been published. This contribution investigates the genetics of treatment-resistant schizophrenia, testing 384 candidate gene loci related to the neurobiology of the disease. First, we identified a subgroup of treatment-resistant patients in a sample of 240 schizophrenia patients using the American Psychiatric Association criteria and then we genotyped all patients using a custom Illumina Bead Chip comprising of 384 single nucleotide polymorphisms. We screened all markers for nominal significance and for statistical significance after multiple-testing correction. The most significant single nucleotide polymorphism was the rs2152324 marker in the NALCN gene (P=0.004); however, after the FDR correction, the P-value was not significant. Our analysis of 384 markers across candidate genes did not indicate any robust association with treatment-resistant schizophrenia. However, this phenotype can be assessed retrospectively in cross-sectional studies and these preliminary results point out the importance of choosing alternative phenotypes in psychiatric pharmacogenetics.

The brain-derived neurotrophic factor gene in suicidal behaviour: a meta-analysis.

Suicide is a prominent public health problem. Its aetiology is complex, and the brain-derived neurotrophic factor (BDNF) has been implicated. We performed the first meta-analysis of the functional BDNF marker Val66Met (rs6265, 196G>A) in suicidal behaviour using data from 11 previously published samples plus our present sample (total n=3352 subjects, 1202 with history of suicidal behaviour. The meta-analysis including all 12 studies showed a trend for the Met-carrying genotypes and Met allele conferring risk for suicide (random-effects model p=0.096; ORMet-carrier=1.13, 95% CI 0.98-1.30, and random-effects model p=0.032; ORMet=1.16, 95% CI 1.01-1.32, respectively). Furthermore, we found the Met allele and the Met allele-carrying genotypes to be associated with history of suicide attempt (eight studies; allelic meta-analysis--random-effects model: p=0.013; fixed-effects model: p=0.006; genotypic meta-analysis--random-effects model: p=0.017; fixed-effects model: p=0.008). Taken together, the results from our study suggest that BDNF Val66Met is involved in suicidality. Further studies are required to elucidate its role in suicidal behaviour.