Pharmacogenetics Of Antidepressants Research Articles

Association between 5-HTR1A gene C-1019G polymorphism and antidepressant response in patients with major depressive disorder: A meta-analysis.

Major depressive disorder (MDD) is a substantial global health concern, and its treatment is complicated by the variability in individual response to antidepressants. To consolidate research and clarify the impact of genetic variation on MDD treatment outcomes. Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search across PubMed, EMBASE, Web of Science, and the Cochrane Library was conducted without date restrictions, utilizing key terms related to MDD, serotonin 1A receptor polymorphism (5-HTR1A), C-1019G polymorphism, and antidepressant response. Studies meeting inclusion criteria were thoroughly screened, and quality assessed using the Newcastle-Ottawa Scale. Statistical analyses, including χ 2 and I² values, were used to evaluate heterogeneity and fixed-effect or random-effect models were applied accordingly. The initial search yielded 1216 articles, with 11 studies meeting criteria for inclusion. Analysis of various genetic models showed no significant association between the 5-HTR1A C-1019G polymorphism and antidepressant efficacy. The heterogeneity was low to moderate, and no publication bias was detected through funnel plot symmetry and Egger's and Begg's tests. This meta-analysis does not support a significant association between the 5-HTR1A C-1019G polymorphism and the efficacy of antidepressant treatment in MDD. The findings call for further research with larger cohorts to substantiate these results and enhance the understanding of antidepressant pharmacogenetics.

Role of Pharmacokinetics and Pharmacogenetics of Antidepressant-Induced Prolongation of the QT Interval and Torsade de Pointes in Patients with Mental Disorders

Antidepressants (ADs) include drugs of various pharmacological groups, which are mainly used for the treatment of mental disorders (major depressive disorder, obsessive-compulsive disorder, social phobia, panic disorder, generalized anxiety disorder, post-traumatic stress disorder), chronic pain and addiction diseases. Chronic use of ADs can lead to the development of cardiotoxic adverse drug reactions (ADRs). The most important cardiotoxic AD-induced ADRs are prolongation of the QT interval, ventricular tachycardia of the "pirouette" type (Torsades de Pointes - TdP). This narrative review analyzes and summarizes the results of studies on pharmacokinecis and pharmacogenetics of ADs on QT interval prolongation and updates physicians' knowledge of the risk of developing AD-induced TdP in patients with psychiatric disorders.

Pharmacogenetics of antidepressants (from history to the present)

Pharmacogenetics is a relatively new scientific discipline, which is currently the main tool in personalized medicine. The aim of research in this area is to identify significant genetic markers for the introduction of their accounting in routine clinical practice. Generalization of data on the patient’s phenotype should be the key to predicting the pharmacokinetics and pharmacodynamics of the drug in the body. A personalized approach based on pharmacogenetic research data in psychiatry is extremely relevant due to the high social and budgetary costs of treating mental disorders around the world. Currently, there are data on the pharmacogenetics of most modern antidepressants, however, conducting such studies in patients with depressive disorders in most cases is impossible for implementation in routine clinical practice due to the impossibility of conducting the test in the laboratory of medical organizations and the lack of specialists competent in the clinical interpretation of the results of pharmacogenetic testing.

Pharmacogenetics of Antidepressants: from Genetic Findings to Predictive Strategies

The constantly growing contribution of depressive disorders to the global disease statistics calls for a growth of treatment effectiveness and optimization. Antidepressants are the most frequently prescribed medicines for depressive disorders. However, development of a standardized pharmacotherapeutic approach is burdened by the genomic heterogeneity, lack of reliable predictive biomarkers and variability of the medicines metabolism aggravated by multiple side effects of antidepressants. According to modern assessments up to 20 % of the genes expressed in our brain are involved in the pathogenesis of depression. Large-scale genetic and genomic research has found a number of potentially prognostic genes. It has also been proven that the effectiveness and tolerability of antidepressants directly depend on the variable activity of the enzymes that metabolize medicines. Almost all modern antidepressants are metabolized by the cytochrome P450 family enzymes. The most promising direction of research today is the GWAS (Genome-Wide Association Study) method that is aimed to link genomic variations with phenotypical manifestations. In this type of research genomes of depressive patients with different phenotypes are compared to the genomes of the control group containing same age, sex and other parameters healthy people. Notably, regardless of the large cohorts of patients analyzed, none of the GWA studies conducted so far can reliably reproduce the results of other analogous studies. The explicit heterogeneity of the genes associated with the depression pathogenesis and their pleiotropic effects are strongly influenced by environmental factors. This may explain the difficulty of obtaining clear and reproducible results. However, despite any negative circumstances, the active multidirectional research conducted today, raises the hope of clinicians and their patients to get a whole number of schedules how to achieve remission faster and with guaranteed results

Pharmacogenetics in psychiatry: state of the art

In this article, the current literature on pharmacogenetics of antidepressants, antipsychotics and lithium are summarized by the section of Neurobiology and Genetics of the German Society of Psychiatry, Psychotherapy and Neurology (DGPPN). The publications of international expert groups and regulatory authorities are reviewed and discussed. In Germany, astatement on pharmacogenetics was also made by the gene diagnostics committee of the Ministry of Health. The DGPPN supports two recommendations: 1)to perform CYP2D6 genetic testing prior to prescription of tricyclic antidepressants and 2)to determine the HLA-B*1502 genotype in patients of Asian origin before using carbamazepine. The main obstacle for abroad application of pharmacogenetic tests in psychiatry remains the lack of large prospective studies, for both single gene-drug pair and cobinatorial pharmacogenetic tests, to evaluate the benefits of genetic testing. Psychiatrists, geneticists and funding agencies are encouraged to increase their efforts for the future benefit of psychiatric patients.

The association of β-arrestin2 polymorphisms with response to antidepressant treatment in depressed patients

The study of genetic polymorphisms involved in antidepressants (AD) response is essential to provide a personalized medicine approach in the field of depression. β-arrestin 2 (ARRB2) is a candidate gene in the pharmacogenetics of AD as it is involved in the signaling cascade downstream of numerous neurotransmitter receptors. We investigated the association between five ARRB2 single nucleotide polymorphisms (SNPs): rs1045280, rs2036657, rs4790694, rs3786047 and rs452246, and response to AD treatment in a sample of 569 patients with a major depressive episode treated for 6months. We show that GG/GT patients for rs4522461 (n=534) and AA/AC patients for rs4790694 (n=244) have a lower response to AD than other genotype groups (HDRS score of 10.9 vs 8.0 after 6months, multivariate analysis: p=0.03; 12.2 vs 9.6, p=0.02, respectively). These data provide additional evidence that β-arrestin 2 is a regulator of intracellular signal transduction processes involved in AD treatment.

Pharmacogenetics of Antidepressants, A Review of Significant Genetic Variants in Different Populations

Major depressive disorder is a highly prevalent disease that is challenging to treat, often requiring medication and dose adjustments. Genetic factors play an important role in psychotropic medication responses. However, the translation of pharmacogenetics findings to clinical recommendations with regards to antidepressant responses is still in its early stages. We reviewed recent primary research articles, meta-analyses, and reviews on the pharmacogenetics of antidepressant treatment for major depressive disorder in different populations. We identified eight genes with likely associations with treatment responses and summarized genetic variants most likely to influence treatment responses. We determined the frequency of these variants in Caucasian, Asian, Hispanic, and African American populations. The genes are related to functions in drug metabolism, transport, signalling, stress response, and neuroplasticity. Clinical recommendations already exist for CYP2D6 and CYP2C19 cytochrome P450 drug metabolism genes. The other genes are: ABCB1 with single nucleotide polymorphisms (SNPs) rs2032583 and rs2235015; FKBP5 with SNPs rs1360780, rs3800373, and rs4713916; GNB3 with SNP rs5443; BDNF with SNP rs6265; HTR2A with SNPs rs7997012 and rs6313; and SLC6A4 with polymorphisms 5-HTTLPR and STin2. There is significant variability of the frequencies of these polymorphisms in the different populations we reviewed. There is also variability in the antidepressant responses between populations carrying the same polymorphism in some cases, indicating a likely polygenic influence. Future studies in the pharmacogenetics of antidepressants would benefit from including more subjects from underrepresented ethnic groups and stratifying results.

Pharmacogenetics of major depressive disorder: top genes and pathways toward clinical applications.

The pharmacogenetics of antidepressants has been not only a challenging but also frustrating research field since its birth in the 1990s. Indeed, great expectations followed the first evidence of familiar aggregation of antidepressant response. Despite the progress from candidate gene studies to genome-wide association studies (GWAS), results fell out the expectations and they were often inconsistent. Anyway, the cumulative evidence supports the involvement of some genes and molecular pathways in antidepressant efficacy. The best single genes are SLC6A4, HTR2A, BDNF, GNB3, FKBP5, ABCB1, and cytochrome P450 genes (CYP2D6 and CYP2C19). Molecular pathways involved in inflammation and neuroplasticity show the greatest support. The first studies evaluating benefits of genotype-guided antidepressant treatments provided encouraging results and confirmed the relevance of SLC6A4, HTR2A, ABCB1, and cytochrome P450 genes. Further progress in genotyping and data analysis would allow to move forward and complete the understanding of antidepressant pharmacogenetics and its translation into clinical applications.

PPP3CC gene: a putative modulator of antidepressant response through the B-cell receptor signaling pathway

Antidepressant pharmacogenetics represents a stimulating, but often discouraging field. The present study proposes a combination of several methodologies across three independent samples. Genes belonging to monoamine, neuroplasticity, circadian rhythm and transcription factor pathways were investigated in two samples (n=369 and 88) with diagnosis of major depression who were treated with antidepressants. Phenotypes were response, remission and treatment-resistant depression. Logistic regression including appropriate covariates was performed. Genes associated with outcomes were investigated in the STAR*D (Sequenced Treatment Alternatives to Relieve Depression) genome-wide study (n=1861). Top genes were further studied through a pathway analysis. In both original samples, markers associated with outcomes were concentrated in the PPP3CC gene. Other interesting findings were particularly in the HTR2A gene in one original sample and the STAR*D. The B-cell receptor signaling pathway proved to be the putative mediator of PPP3CC's effect on antidepressant response (P=0.03). Among innovative candidates, PPP3CC, involved in the regulation of immune system and synaptic plasticity, seems promising for further investigation.

From pharmacogenetics to pharmacogenomics: the way toward the personalization of antidepressant treatment.

Major depressive disorder is the most common psychiatric disorder, worldwide, yet response and remission rates are still unsatisfactory. The identification of genetic predictors of antidepressant (AD) response could provide a promising opportunity to improve current AD efficacy through the personalization of treatment. The major steps and findings along this path are reviewed together with their clinical implications and limitations. We systematically reviewed the literature through MEDLINE and Embase database searches, using any word combination of "antidepressant," "gene," "polymorphism," "pharmacogenetics," "genome-wide association study," "GWAS," "response," and "adverse drug reactions." Experimental works and reviews published until March 2012 were collected and compared. Numerous genes pertaining to several functional systems were associated with AD response. The more robust findings were found for the following genes: solute carrier family 6 (neurotransmitter transporter), member 4; serotonin receptor 1A and 2A; brain-derived neurotrophic factor; and catechol-O-methyltransferase. Genome-wide association studies (GWASs) provided many top markers, even if none of them reached genome-wide significance. AD pharmacogenetics have not produced any knowledge applicable to routine clinical practice yet, as results were mainly inconsistent across studies. Despite this, the rising awareness about methodological deficits of past studies could allow for the identication of more suitable strategies, such as the integration of the GWAS approach with the candidate gene approach, and innovative methodologies, such as pathway analysis and study of depressive endophenotypes.

Antidepressant pharmacogenetics

This article reviews recent literature published over the period March 2012-August 2013 on antidepressant pharmacogenetics, with a focus on clinical translation and methodological challenges. Recently, various polymorphisms associated with differential antidepressant efficacy, tolerability, and safety have emerged in association studies, but mixed findings, limited effect sizes, and poor control of confounders have prevented findings translating to practice. Although promising steps have been made, empirically robust clinically translatable pharmacogenetic tests are not yet established. The complex neurobiology of major depressive disorder (MDD) together with the evolving understanding of genetic processes present research challenges for clinical translation. Early reports of clinical utility are published. The current evidence base for antidepressant pharmacogenetics is, however, not yet empirically robust enough to inform routine prescribing guidelines. Over the coming years, genetically guided versus unguided trials will help determine if antidepressant pharmacogenetics merits more widespread application.

Pharmacogenetics of antidepressant drugs: An update after almost 20 years of research

Major depressive disorder (MDD) is an emergent cause of personal and socio-economic burden, both for the high prevalence of the disorder and the unsatisfying response rate of the available antidepressant treatments. No reliable predictor of treatment efficacy and tolerance in the single patient is available, thus drug choice is based on a trial and error principle with poor clinical efficiency. Among modulators of treatment outcome, genetic polymorphisms are thought to explain a significant share of the inter-individual variability. The present review collected the main pharmacogenetic findings primarily about antidepressant response and secondly about antidepressant induced side effects, and discussed the main strengths and limits of both candidate and genome-wide association studies and the most promising methodological opportunities and challenges of the field. Despite clinical applications of antidepressant pharmacogenetics are not available yet, previous findings suggest that genotyping may be applied in the clinical practice. In order to reach this objective, further rigorous pharmacogenetic studies (adequate sample size, study of better defined clinical subtypes of MDD, adequate covering of the genetic variability), their combination with the results obtained through complementary methodologies (e.g., pathway analysis, epigenetics, transcriptomics, and proteomics), and finally cost-effectiveness trials are required.

Pharmacogenetics in major depression: A comprehensive meta-analysis

A number of candidate gene studies focused on major depression (MD) and antidepressant (AD) efficacy have been carried out, but results mainly remain inconclusive. We performed a comprehensive meta-analysis of published candidate gene studies focused on AD efficacy in MD to evaluate the cumulative evidence. A random-effect model was applied to study the polymorphisms with genotypic counts available from at least three independent studies. On the base of previous evidence, the analysis was stratified by ethnicity (Caucasian, Asian, and other/mixed), and AD class (SSRIs and mixed/other ADs). Genotypic data were available for 16 polymorphisms in 11 genes. After the exclusion of 5-HTTLPR in SLC6A4 included in another recent meta-analysis, 15 polymorphisms in 11 genes were included in the present meta-analysis (BDNF rs6265, SLC6A4 STin2, HTR1A rs6295, HTR2A rs6311, rs6313 and rs7997012, HTR6 rs1805054, TPH1 rs1800532, SLC6A2 rs5569, COMT rs4680, GNB3 rs5443, FKBP5 rs1360780 and rs3800373, and ABCB1 rs1045642 and rs2032582). Our results suggested that BDNF rs6265 (Val66Met) heterozygous genotype was associated with better SSRIs response compared to the homozygous genotypes, particularly in Asians (OR=1.53, 95%CI 1.12-2.07, p=0.007). SLC6A4 STin2, HTR2A rs6311 and rs7997012, GNB3 rs5443, FKBP5 rs1360780 and rs3800373, and ABCB1 rs2032582 showed associations with AD efficacy, but these results were highly dependent on one or two single studies. In conclusion, our findings suggested the BDNF Val66Met as the best single candidate involved in AD response, with a selective effect on SSRI treatment. Our overall results supported no major effect of any single gene variant on AD efficacy.

Adrenergic Receptor Gene Variation and Selective Norepinephrine Reuptake Inhibitors

Adrenergic Receptor Gene Variation and Selective Norepinephrine Reuptake Inhibitors

Genetics and Personalized Medicine in Antidepressant Treatment

Antidepressant medication is a major cornerstone in treatment of mood and anxiety disorders. Numerous substances are available on the market; however, only 60% of treated patients show sufficient response to medication and side effects are common. Lengthy trials are not uncommon until the optimized drug and dose is found and unfortunately, no valid predictors to match the 'right' drug to the 'right' patient exist nowadays. Genetic factors are thought to be involved as evidenced by numerous pharmacogenetic studies. This comprehensive review summarizes the most interesting findings and discusses clinical implications of pharmacogenetic results. We reviewed available literature on pharmacogenetics of antidepressant response and side effects until summer 2011 using the PubMed database. Promising findings exist for several variants in candidate genes involved in the pharmacokinetics or pharmacodynamics of antidepressants. These include association findings in the serotonin transporter gene (5-HTT), serotonin receptor genes, a gene coding an efflux pump in the blood-brain-barrier (ABCB1), and genes involved in the HPA axis. Promising candidate genes increasing risk for side effects include some of the genes associated with treatment response and cytochrome P450 genes. A high number of studies on pharmacogenetics of antidepressants have been published during the past decades. However, contradictory results still limit clinical use of these findings. Future studies should include functional analyses and consider gene-gene and gene-environment interactions. This will aid in facilitating a future use of pharmacogenetics in clinical practice, likely leading to improved patient care.

Association between the 5-HT1A receptor gene polymorphism (rs6295) and antidepressants

Previous studies have implicated 5-HT1A receptor gene (HTR1A) polymorphisms in the therapeutic response to antidepressants, especially selective serotonin reuptake inhibitors. A functional HTR1A C-1019G polymorphism (rs6295) in the promoter region was found to be associated with antidepressant pharmacogenetics in different populations. However, inconsistent and inconclusive results have been obtained. In this study, we tested whether rs6295 genetic variants are related to antidepressant effects using a meta-analysis method. The relevant literature was acquired through deliberate searching and selection based on the established inclusion criteria for publications. A total of 10 articles were identified, all of which evaluated the HTR1A C-1019G polymorphism and antidepressant response. Dominant and recessive models were tested in the analyses, and the results revealed no association between the HTR1A C-1019G polymorphism and antidepressant response.

Importance of genomic studies for drug withdrawal with mental toxicities

Undesired side-effects and toxicities of drugs, especially in the area of new-drug development, are negligibleless, unpredicable and often disastrous once being encountered. The suicidal behavior caused by antidepressant treatment is a typical of clinical evidence recently being discovered. We previously hypothesized that patients’ genetic status would decide the suicidal incident rate of antidepressants - it is pharmacogenetics of antidepressants may contribute of this toxicity in patients. In this review, we discuss this problem by comparing many strings of pharmacogenomics evidence of antidepressants recently being published with many other strings of evidence such as drug withdrawal with hepatotoxicity. We argue herein that pharmacogenetics may be very useful in drug withdrawal for mental toxicity. Because this is low-incidence toxicities, which are more reliable on human’s genetic characteristics. We stress the importance of genomics studies for drug withdrawal in future.

Biomarcadores de la depresión

The delay in the actions of antidepressants as well as the percentage of patients that do not respond to antidepressant treatment, give rise to a keen interest in the development of biomarkers of therapeutic efficacy in depression, but it is also of importance to work towards the development of biomarkers of vulnerability, diagnosis and prognosis of this disorder. To analyze what is known of the main genetic, molecular and biochemical biomarkers of depression already validated, and to discuss the present and future of this research field. Among the most repeatedly validated biomarkers of depression are the decrease in serotonin transporter binding in platelets and lymphocytes, hypercortisolemia, hypocholesteremia, decrease in brain-derived neurotrophic factor, decrease in CREB phosphorylation, and an increase in interleukin 6. Some biomarkers related to the pharmacogenetics of antidepressants are already a reality, now the next step will be to develop biomarkers of pathophysiological processes that correlate with important clinical aspects of depression.

Research Highlights

Research Highlights

Proteomic analysis of rat hippocampus exposed to the antidepressant paroxetine

Antidepressant drugs can exert significant effects on the mood of a patient suffering major depression and other disorders. These drugs generally have pharmacological actions on the uptake or metabolism of the neurotransmitters serotonin, noradrenaline and, to a lesser extent, dopamine. However, there are many aspects of antidepressant action we do not understand. We have applied proteomic analysis in a rat hippocampal model in an attempt to identify relevant molecules that operate in pathways functionally relevant to antidepressant action. Rats were administered either 5 mg/kg daily of the antidepressant paroxetine or vehicle for 12 days, then hippocampal protein was recovered and resolved by 2-D gel electrophoresis. After antidepressant exposure, we observed increased expression or modification of cytochrome c oxidase, subunit Va, cyclin-dependent kinase inhibitor 2A interacting protein, dynein, axonemal, heavy polypeptide 3 and RHO GDP-dissociation inhibitor alpha. Decreased expression or modification was observed for complexin 1 (CPLX1), alpha-synuclein, parvalbumin, ribosomal protein large P2, prohibitin, nerve growth factor, beta subunit (NGFB), peroxiredoxin 6 (PRDX6), 1-acylglycerol-3-phosphate O-acyltransferase 2_predicted, cystatin B (CYTB) and lysosomal membrane glycoprotein 1. CPLX1, the most strongly regulated protein observed, mediates the fusion of cellular transport vesicles with their target membranes and has been implicated in the pathophysiology of mood disorders, as well as antidepressant action. CPLX1 and the other proteins identified may represent links into molecular processes of importance to mood dysregulation and control, and their respective genes may represent novel candidates for studies of antidepressant pharmacogenetics.