Therapeutic Response In Major Depressive Disorder Research Articles

Associations Between Gut Microbiota and Treatment Response in Patients With Major Depressive Disorders Stratified by Dairy Intake: A Prospective Observational Study

Over the last decade, many studies have examined the relationships between major depressive disorder (MDD) and gut microbiota. However, few studies addressed the influence of dairy intake on the associations between gut microbiota and therapeutic response in MDD.

Gene-Based Association Analysis Suggests Association of HTR2A With Antidepressant Treatment Response in Depressed Patients

The serotonin [5-hydroxytryptamine (5-HT)] system has been implicated in the pathogenesis of major depressive disorder (MDD). Among the 5-HT receptor subtypes, 5-HT2 is one of the major pharmacological therapeutic targets for MDD. There have been inconsistent findings in previous pharmacogenetic studies investigating the antidepressant therapeutic response using one or several 5-HT2A (HTR2A) genetic polymorphisms. By using gene-based association analysis, we hope to identify genetic variants of HTR2A which are related to MDD susceptibility and its antidepressant therapeutic response. 288 HTR2A single nucleotide polymorphisms in MDD susceptibility have been investigated through a case–control (455 MDD patients and 2, 998 healthy controls) study, as well as in antidepressant efficacy (n = 455) in our current research. The 21-item Hamilton Rating Scale for Depression was used to evaluate measures of antidepressant therapeutic efficacy. From two MDD groups in the antidepressant therapeutic response, by using gene-based analyses, we have identified 14 polymorphisms as suggestive markers for therapeutic response (13 for remission and 1 for response) in both meta- and mega-analyses. All of these HTR2A reported polymorphisms did not reach statistical significance in the case–control association study. This current investigation supported the link between HTR2A variants and antidepressant therapeutic response in MDD but not with MDD susceptibility.

Plasma amino acid profiling in major depressive disorder treated with selective serotonin reuptake inhibitors.

Amino acids are important body metabolites and seem to be helpful for understanding pathogenesis and predicting therapeutic response in major depressive disorder (MDD). We performed amino acid profiling to discover potential biomarkers in major depressive patients treated with selective serotonin reuptake inhibitors (SSRIs). Amino acid profiling using aTRAQ™ kits for Amino Acid Analysis in Physiological Fluids on a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system was performed on 158 specimens at baseline and at 6 weeks after the initiation of SSRI treatment for 68 patients with MDD and from 22 healthy controls. Baseline alpha-aminobutyric acid (ABA) discriminated the patients according to the therapeutic response. Plasma glutamic acid concentration and glutamine/glutamic acid ratio were different between before and after SSRI treatment only in the response group. Comparing patients with MDD with healthy controls, alterations of ten amino acids, including alanine, beta-alanine, beta-aminoisobutyric acid, cystathionine, ethanolamine, glutamic acid, homocystine, methionine, O-phospho-L-serine, and sarcosine, were observed in MDD. Metabolism of amino acids, including ABA and glutamic acid, has the potential to contribute to understandings of pathogenesis and predictions of therapeutic response in MDD.

GTP cyclohydrolase 1 gene haplotypes as predictors of SSRI response in Japanese patients with major depressive disorder

Tetrahydrobiopterin (BH4) plays an important role in the biosynthesis of serotonin, melatonin and catecholamines, all of which are implicated in the pathophysiology of mood disorders (MDs), including major depressive disorder (MDD) and bipolar disorder (BP). Production of BH4 is regulated by GTP cyclohydrolase transcription and activity. Thus, we considered the GTP cyclohydrolase gene (GCH1) to be a good candidate gene in the pathophysiology of MDs and of the serotonin selective reuptake inhibitors (SSRIs) response in MDD, and conducted a case-control study utilizing three SNPs (rs8007267, rs3783641 and rs841) and moderate sample sizes (405 MDD patients, including 262 patients treated by SSRIs, 1022 BP patients and 1805 controls). A multiple logistic regression analysis was carried out to compare the frequencies of each SNP genotype for the target phenotype across patients and controls in several genetic models, while adjusting for possible confounding factors. A clinical response was defined as a decrease of more than 50% from the baseline score on the Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D) within 8 weeks, and clinical remission as a SIGH-D score of less than 7 at 8 weeks. No associations between three SNPs in GCH1 and MDD or BP were observed; however, GCH1 was associated with SSRI therapeutic response in MDD in all the marker's haplotype analysis (Global P value=0.0379). Results suggest that GCH1 may predict response to SSRI in MDD in the Japanese population. Nevertheless, a replication study using larger samples may be required for conclusive results, since our sample size was small.

Possible association between ubiquitin-specific peptidase 46 gene and major depressive disorders in the Japanese population

Several investigations have reported that abnormalities in circadian rhythms might be related to the pathophysiology of major depressive disorder (MDD) and the therapeutic response to selective serotonin reuptake inhibitors (SSRIs). Recently, ubiquitin-specific peptidase 46 (USP46), a new molecule related to the circadian clock system, has been described. We conducted a case control study between seven tagging SNPs (rs10517263, rs17675844, rs6554557, rs12646800, rs2244291, rs10034164, rs346005) in the USP46 gene, MDD, and the SSRI therapeutic response in MDD in the Japanese population. We recruited 432 MDD patients (202 males and 230 females) and 792 healthy controls (319 males and 473 females). Two hundred sixty-one of 432 MDD patients were treated with SSRIs (fluvoxamine, sertraline or paroxetine). We detected an association between the USP46 gene and MDD in a haplotype analysis (rs2244291-rs10034164-rs346005 and rs12646800-rs2244291-rs10034164-rs346005). However, we did not find any association between the USP46 gene and SSRI response or remission in MDD in the Japanese population. A replication study using larger samples may be required for conclusive results, since our sample size was small. Our results suggest that the USP46 gene might play a role in the pathophysiology of MDD in the Japanese population.

Association analysis of SIGMAR1 with major depressive disorder and SSRI response

Several investigations have suggested the possible involvement of sigma 1 non-opioid intracellular receptor 1 (sigma 1 receptor) in the pathophysiology of major depressive disorder (MDD). Sigma 1 receptors are also one of the major pharmacological therapeutic targets of selective serotonin reuptake inhibitors (SSRIs). To evaluate the association of sigma 1 receptor gene (SIGMAR1) and MDD and SSRIs therapeutic response in MDD, we conducted a case-control study of Japanese samples (466 MDD patients, 516 controls and 208 MDD patients treated by fluvoxamine or sertraline). We defined a clinical response as a decrease of more than 50% in baseline the Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D) within 8 weeks, and clinical remission as an SIGH-D score of less than 7 at 8 weeks. Therefore, we selected rs1800866 in SIGMAR1 for the following association analysis. In the logistic regression analysis, we detected an association of the phenotypes (MDD or controls) with rs1800866 genotype. However, we did not detect an association between rs1800866 and SSRI therapeutic response in Japanese MDD. In addition, remission with SSRI was not associated with rs1800866. Also, we did not detect a novel polymorphism in SIGMAR1 when we performed a mutation search using MDD treated by SSRIs samples. Our results suggest that rs1800866 in SIGMAR1 may play a role in the pathophysiology of MDD in the Japanese population. Also, SIGMAR1 does not play a role in the therapeutic response to SSRI in Japanese MDD patients. However, because our sample was small, a replication study using another population and larger sample will be required for conclusive results.

Genetic Association Analysis of Functional Polymorphisms in Neuronal Nitric Oxide Synthase 1 Gene (NOS1) and Mood Disorders and Fluvoxamine Response in Major Depressive Disorder in the Japanese Population

Background/Aim: Nitric oxide has been reported to play a role in neural transmitter release and N-methyl-D-aspartate receptor activation, as well as to be related to oxidative stress. Abnormalities in both of these mechanisms are thought to be involved in the pathophysiology of mood disorders including major depressive disorder (MDD) and bipolar disorder (BP). In addition, several lines of evidence support an association between abnormalities in neuronal nitric oxide synthases (nNOS) and mood disorders. Therefore, we studied the association of nNOS gene (NOS1) and mood disorders and the efficacy of fluvoxamine treatment in Japanese MDD patients. Materials and Methods: Using a single nucleotide polymorphism (SNP; rs41279104, also called ex1c), we conducted a genetic association analysis of case-control samples (325 MDD patients, 154 BP patients and 807 controls) in the Japanese population. In addition, we performed an association analysis between NOS1 and the efficacy of fluvoxamine treatment in 117 MDD patients. We defined a clinical response as a decrease of more than 50% in baseline SIGH-D (Structured Interview Guide for the Hamilton Rating Scale for Depression) score within 8 weeks, and clinical remission as an SIGH-D score of less than 7 at 8 weeks. Results: We did not detect a significant association between NOS1 and MDD, BP or the fluvoxamine therapeutic response in MDD in allele/genotype-wise analysis. Conclusions: We did not detect an association between only one marker (rs41279104) in NOS1 and Japanese mood disorder patients and fluvoxamine response, but sample sizes were probably too small to allow a meaningful test. Moreover, because we did not perform an association analysis based on linkage disequilibrium and a mutation scan of NOS1, a replication of the study using a larger sample and based on linkage disequilibrium may be required for conclusive results.

Translin-Associated Factor X Gene (TSNAX) may be Associated with Female major Depressive Disorder in the Japanese Population

Several investigations have reported that the translin-associated factor X gene (TSNAX)/disrupted-in-schizophrenia-1 gene (DISC1) was associated with major psychiatric disorders including schizophrenia, bipolar disorder (BP), and major depressive disorder (MDD). TSNAX is located immediately upstream of DISC1, and has been shown to undergo intergenic splicing with DISC1. It thus may also be influenced by translocation. To our knowledge, there are no reported gene-based association analyses between TSNAX and mood disorders in the Japanese population. We conducted a case-control study of Japanese samples (158 bipolar patients, 314 major depressive disorder patients, and 811 controls) with three tagging SNPs in TSNAX, selected using HapMap database. In addition, we performed an association analysis between TSNAX and the efficacy of fluvoxamine treatment in 120 Japanese patients with MDD. The MDD patients in this study had scores of 12 or higher on the 17 items of the Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D). We defined a clinical response as a decrease of more than 50% in baseline SIGH-D within 8 weeks, and clinical remission as an SIGH-D score of less than 7 at 8 weeks. We found an association between rs766288 in TSNAX and female MDD in the allele/genotype analysis. However, we did not find any association between TSNAX and BP or the fluvoxamine therapeutic response in MDD in the allele/genotype analysis or haplotype analysis. Our results suggest that rs766288 in TSNAX may play a role in the pathophysiology of female MDD in the Japanese population. A replication study using larger samples may be required for conclusive results, since our sample size was small.

Orphan Nuclear Receptor Rev-erb Alpha Gene (NR1D1) and Fluvoxamine Response in Major Depressive Disorder in the Japanese Population

Background: Sleep-wake disturbance, frequently observed in major depressive disorder (MDD), negatively influences clinical status. Treatment with antidepressants also reportedly affects circadian rhythms. In a recent in vitro study, the nuclear receptor Rev-erbα was reported to be related to circadian rhythms, and was shown to be involved in the biological action of lithium therapy. Therefore, we examined the association between the orphan nuclear receptor Rev-erbα gene (NR1D1) and the efficacy of fluvoxamine treatment in 118 Japanese patients with major depressive disorder. Methods: The scores of the MDD patients in this study on the 17 items of the Structured Interview Guide for the Hamilton Rating Scale for Depression (SIGH-D) were 12 or higher. We defined a clinical response as a decrease of more than 50% in baseline SIGH-D within 8 weeks and clinical remission as a SIGH-D score of less than 7 at 8 weeks. We selected 3 ‘tagging SNPs’ in NR1D1 for the following association analysis. Results: We did not detect a significant association between NR1D1 and the fluvoxamine therapeutic response in MDD in allele/genotype-wise analysis or haplotype-wise analysis. Conclusion: Our results suggest that NR1D1 does not play a major role in the therapeutic response to fluvoxamine in Japanese MDD patients. However, because our sample was small, a replication study using another population and a larger sample will be required for conclusive results.

Association analysis of Group II metabotropic glutamate receptor genes ( GRM2 and GRM3) with mood disorders and fluvoxamine response in a Japanese population

Background Several lines of evidence implicate abnormalities in glutamate neural transmission in the pathophysiology of mood disorders, including major depressive disorder (MDD) and bipolar disorder (BP). Preclinical antidepressant effects were also reported for group II metabotropic glutamate receptor (Group II mGluRs) antagonists show dose-dependent antidepressant-like effects in murine models of depression. Also, it has been suggested that abnormalities in the hypothalamic-pituitary-adrenal axis and serotonergic neural transmission are important mechanisms in the pathophysiology of mood disorders. Group II mGluRs play an important role in regulating the function of these mechanisms. From these results, it has been suggested that abnormalities in Group II mGluRs might be involved in the pathophysiology of mood disorders, including MDD) and BP, and may influence the clinical response to treatment with SSRIs in MDD. Therefore, we studied the association between Group II mGluR genes ( GRM2 and GRM3) and mood disorders and the efficacy of fluvoxamine treatment in Japanese MDD patients. Materials and methods Using three tagging SNPs in GRM2 and an SNP (rs6465084) reported functional variant in GRM3, we conducted a genetic association analysis of case-control samples (325 MDD patients, 155 BP patients and 802 controls) in the Japanese population. In addition, we performed an association analysis of GRM2 and GRM3 and the efficacy of fluvoxamine treatment in 117 Japanese patients with MDD. The MDD patients in this study had scores of 12 or higher on the 17 items of the Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D). We defined a clinical response as a decrease of more than 50% in baseline SIGH-D within 8 weeks, and clinical remission as an SIGH-D score of less than 7 at 8 weeks. Results We found an association between rs6465084 in GRM3 and MDD in the allele-wise analysis after Bonferroni's correction ( P-value = 0.0371). However, we did not find any association between GRM3 and BP or the fluvoxamine therapeutic response in MDD in the allele/genotype-wise analysis. We also did not detect any association between GRM2 and MDD, BP or the fluvoxamine therapeutic response in MDD in the allele/genotype-wise or haplotype-wise analysis. Discussion We detected an association between only one marker (rs6465084) in GRM3 and Japanese MDD patients. However, because we did not perform an association analysis based on LD and a mutation scan of GRM3, a replication study using a larger sample and based on LD may be required for conclusive results.

CLOCK may Predict the Response to Fluvoxamine Treatment in Japanese Major Depressive Disorder Patients

Recent studies have shown that selective serotonin reuptake inhibitors (SSRIs) have circadian properties, suggesting that the antidepressive action of SSRIs may also be attributable to circadian mechanisms. Another study reported an association between clock gene (CLOCK) and improvements in insomnia symptoms from SSRIs treatment. Therefore, we examined the association between CLOCK and the efficacy of fluvoxamine treatment in 121 patients with Japanese major depressive disorder (MDD). The MDD patients in this study had scores of 12 or higher on the 17 items of the Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D). We defined a therapeutic response as a decrease of more than a 50% in baseline SIGH-D within 8 weeks, and clinical remission as a SIGH-D score of less than seven at 8 weeks. We selected three tagging SNPs in CLOCK for the subsequent statistical association analysis. We detected a significant association between rs3736544, a synonymous polymorphism in exon 20, and the fluvoxamine therapeutic response in MDD in the allele/genotype-wise analyses. In addition, remission with fluvoxamine was also significantly associated with rs3736544. These associations remained significant after Bonferroni correction. Moreover, haplotype analysis findings supported these significant associations, which appeared to be due mainly to rs3736544, in the fluvoxamine therapeutic remission. Our results indicate that CLOCK genotype may be a predictor of fluvoxamine treatment response in Japanese MDD. However, our sample size was small, and a replication study using larger samples may be required for conclusive results.