Factors causing a relapse of major depressive disorders following successful electroconvulsive therapy:A retrospective cohort study

BACKGROUND Electroconvulsive therapy(ECT)is used to treat major depressive disorder(MDD).Relapse is often observed even after successful ECT,followed by adequate pharmaceutical treatment for MDD.AIM To investigate the diagnostic factors and treatment strategies associated with depression relapse.METHODS We analyzed the relationships between relapse,the diagnostic change from MDD to bipolar disorder(BP),and treatment after the initial ECT.We performed a 3-year retrospective study of the prognoses of 85 patients of the Shiga University of Medical Science Hospital.The relative risk of relapse of depressive symptoms was calculated based on the diagnostic change from MDD to BP.A receiver operating characteristic(ROC)curve was generated to evaluate the predictive accuracy of diagnostic changes from MDD to BP based on the duration between the first course of ECT and the relapse of depressive symptoms.RESULTS Eighty-five patients initially diagnosed with MDD and successfully treated with ECT were enrolled in the study.Compared with the MDD participants,more BP patients experienced relapses and required continuation and/or maintenance ECT to maintain remission(65.6%vs 15.1%,P<0.001;relative risk=4.35,95%CI:2.19-8.63,P<0.001).Twenty-nine patients experienced relapses during the three-year follow-up.In 21(72.4%,21/29)patients with relapse,the diagnosis was changed from MDD to BP.The duration from the first course of ECT to relapse was shorter for the BP patients than for the MDD patients(9.63±10.4 mo vs 3.38±3.77 mo,P=0.022);for most patients,the interval was less than one month.The relative risk of depressive symptoms based on diagnostic changes was 4.35(95%confidence interval:2.19–8.63,P<0.001),and the area under the ROC curve for detecting diagnostic changes based on relapse duration was 0.756(95%CI:0.562-0.895,P=0.007).CONCLUSION It may be beneficial to suspect BP and change the treatment strategy from MDD to BP for patients experiencing an early relapse.

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

Multimodal abnormalities of brain structures in adolescents and young adults with major depressive disorder:An activation likelihood estimation meta-analysis

BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging studies.Activation likeli-hood estimation(ALE)offers a method to synthesize these diverse findings and identify consistent brain anomalies.METHODS We performed a comprehensive literature search in PubMed,Web of Science,Embase,and Chinese National Knowledge Infrastructure databases for neuroi-maging studies on MDD among adolescents and young adults published up to November 19,2023.Two independent researchers performed the study selection,quality assessment,and data extraction.The ALE technique was employed to synthesize findings on localized brain function anomalies in MDD patients,which was supplemented by sensitivity analyses.RESULTS Twenty-two studies comprising fourteen diffusion tensor imaging(DTI)studies and eight voxel-based morphome-try(VBM)studies,and involving 451 MDD patients and 465 healthy controls(HCs)for DTI and 664 MDD patients and 946 HCs for VBM,were included.DTI-based ALE demonstrated significant reductions in fractional anisotropy(FA)values in the right caudate head,right insula,and right lentiform nucleus putamen in adolescents and young adults with MDD compared to HCs,with no regions exhibiting increased FA values.VBM-based ALE did not demonstrate significant alterations in gray matter volume.Sensitivity analyses highlighted consistent findings in the right caudate head(11 of 14 analyses),right insula(10 of 14 analyses),and right lentiform nucleus putamen(11 of 14 analyses).CONCLUSION Structural alterations in the right caudate head,right insula,and right lentiform nucleus putamen in young MDD patients may contribute to its recurrent nature,offering insights for targeted therapies.

Resting-state functional magnetic resonance imaging and support vector machines for the diagnosis of major depressive disorder in adolescents

BACKGROUND Research has found that the amygdala plays a significant role in underlying pathology of major depressive disorder(MDD).However,few studies have explored machine learning-assisted diagnostic biomarkers based on amygdala functional connectivity(FC).AIM To investigate the analysis of neuroimaging biomarkers as a streamlined approach for the diagnosis of MDD in adolescents.METHODS Forty-four adolescents diagnosed with MDD and 43 healthy controls were enrolled in the study.Using resting-state functional magnetic resonance imaging,the FC was compared between the adolescents with MDD and the healthy controls,with the bilateral amygdala serving as the seed point,followed by statistical analysis of the results.The support vector machine(SVM)method was then applied to classify functional connections in various brain regions and to evaluate the neurophysiological characteristics associated with MDD.RESULTS Compared to the controls and using the bilateral amygdala as the region of interest,patients with MDD showed significantly lower FC values in the left inferior temporal gyrus,bilateral calcarine,right lingual gyrus,and left superior occipital gyrus.However,there was an increase in the FC value in Vermis-10.The SVM analysis revealed that the reduction in the FC value in the right lingual gyrus could effectively differentiate patients with MDD from healthy controls,achieving a diagnostic accuracy of 83.91%,sensitivity of 79.55%,specificity of 88.37%,and an area under the curve of 67.65%.CONCLUSION The results showed that an abnormal FC value in the right lingual gyrus was effective as a neuroimaging biomarker to distinguish patients with MDD from healthy controls.

Sleep disturbances and psychomotor retardation in the prediction of cognitive impairments in patients with major depressive disorder

BACKGROUND Symptoms of depression and comorbid anxiety are known risk factors for cognitive impairment in major depressive disorder(MDD).Understanding their relationships is crucial for developing targeted interventions to mitigate cognitive impairments in MDD patients.We expect that the severity of sleep disturbances and other depressive symptoms will be positively correlated with the degree of cognitive impairments.We also hypothesize that anxiety symptoms,especially psychic anxiety,is a key factor in predicting cognitive performance in MDD patients and may indirectly contribute to cognitive impairment by affecting sleep disturbances and other potential factors.AIM To determine which dimension of the depressive and anxiety symptoms predicts cognitive impairment during a depressive episode.METHODS A comprehensive neurocognitive test battery assessed executive function,attention,processing speed,and memory in 162 medication-free MDD patients and 142 matched healthy controls.The 24-item Hamilton Depression Rating Scale was used to assess depressive symptoms,and the 14-item Hamilton Anxiety Scale was used to assess anxiety symptoms.Linear regression analyses and mediation analyses were conducted to evaluate the impact of depressive and anxiety symptoms,as well as their interactions,on cognitive impairments.RESULTS Among the depressive symptoms,sleep disturbances were associated with poorer executive function(P=0.004),lower processing speed(P=0.047),and memory impairments(P<0.001),and psychomotor retardation(PR)was associated with lower processing speed in patients with MDD(P=0.019).Notably,PR was found to mediate the impact of sleep disturbances on the processing speed.Regarding anxiety symptoms,psychic anxiety,rather than somatic anxiety,was associated with cognitive impairments in all aspects.Sleep disturbances mediated the effect of psychic anxiety on executive function[β=-0.013,BC CI(-0.027,-0.001)]and memory[β=-0.149,BC CI(-0.237,-0.063)],while PR mediated its effect on processing speed(β=-0.023,BC CI(-0.045,-0.004)].CONCLUSION Sleep disturbances may be a key predictor of poorer executive function,lower processing speed,and memory loss,while PR is crucial for lower processing speed during a depressive episode.Psychic anxiety contributes to all aspects of cognitive impairments,mediated by sleep disturbances and PR.

Major depressive disorder is associated with mitochondrial ND6 T14502C mutation in two Han Chinese families

BACKGROUND Globally,the World Health Organization ranks major depressive disorder(MDD)as the leading cause of disability.However,MDD molecular etiology is still poorly understood.AIM To explore the possible association between mitochondrial ND6 T14502C mutation and MDD.METHODS Clinical data were collected from two pedigrees,and detailed mitochondrial genomes were obtained for the two proband members.The assessment of the resulting variants included an evaluation of their evolutionary conservation,allelic frequencies,as well as their structural and functional consequences.Detailed mitochondrial whole genome analysis,phylogenetic,and haplotype analysis were performed on the probands.RESULTS Herein,we reported the clinical,genetic,and molecular profiling of two Chinese families afflicted with MDD.These Chinese families exhibited not only a range of onset and severity ages in their depression but also extremely low penetrances to MDD.Sequence analyses of mitochondrial genomes from these pedigrees have resulted in the identification of a homoplasmic T14502C(I58V)mutation.The polymorphism is located at a highly conserved isoleucine at position 58 of ND6 and distinct mitochondrial DNA(mtDNA)polymorphisms originating from haplogroups M10 and H2.CONCLUSION Identifying the T14502C mutation in two individuals with no genetic relation who exhibit symptoms of depression provides compelling evidence that this mutation may be implicated in MDD development.Nonetheless,the two Chinese pedigrees that carried the T14502C mutation did not exhibit any functionally significant mutations in their mtDNA.Therefore,the phenotypic expression of the T14502C mutation related to MDD may be influenced by the nuclear modifier gene(s)or environmental factors.

Vulnerable brain regions in adolescent major depressive disorder:A resting-state functional magnetic resonance imaging activation likelihood estimation meta-analysis

BACKGROUND Adolescent major depressive disorder(MDD)is a significant mental health concern that often leads to recurrent depression in adulthood.Resting-state functional magnetic resonance imaging(rs-fMRI)offers unique insights into the neural mechanisms underlying this condition.However,despite previous research,the specific vulnerable brain regions affected in adolescent MDD patients have not been fully elucidated.AIM To identify consistent vulnerable brain regions in adolescent MDD patients using rs-fMRI and activation likelihood estimation(ALE)meta-analysis.METHODS We performed a comprehensive literature search through July 12,2023,for studies investigating brain functional changes in adolescent MDD patients.We utilized regional homogeneity(ReHo),amplitude of low-frequency fluctuations(ALFF)and fractional ALFF(fALFF)analyses.We compared the regions of aberrant spontaneous neural activity in adolescents with MDD vs healthy controls(HCs)using ALE.RESULTS Ten studies(369 adolescent MDD patients and 313 HCs)were included.Combining the ReHo and ALFF/fALFF data,the results revealed that the activity in the right cuneus and left precuneus was lower in the adolescent MDD patients than in the HCs(voxel size:648 mm3,P<0.05),and no brain region exhibited increased activity.Based on the ALFF data,we found decreased activity in the right cuneus and left precuneus in adolescent MDD patients(voxel size:736 mm3,P<0.05),with no regions exhibiting increased activity.CONCLUSION Through ALE meta-analysis,we consistently identified the right cuneus and left precuneus as vulnerable brain regions in adolescent MDD patients,increasing our understanding of the neuropathology of affected adolescents.

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

BACKGROUND Major depressive disorder(MDD)is a substantial global health concern,and its treatment is complicated by the variability in individual response to antide-pressants.AIM To consolidate research and clarify the impact of genetic variation on MDD treatment outcomes.METHODS 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,includingχ2 and I²values,were used to evaluate heterogeneity and fixed-effect or random-effect models were applied accordingly.RESULTS 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.CONCLUSION 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.

Death-associated protein kinase 1 is associated with cognitive dysfunction in major depressive disorder

We previously showed that death-associated protein kinase 1(DAPK1)expression is increased in hippocampal tissue in a mouse model of major depressive disorde and is related to cognitive dysfunction in Alzheimer's disease.In addition,depression is a risk factor for developing Alzheimer's disease,as well as an early clinical manifestation of Alzheimer's disease.Meanwhile,cognitive dysfunction is a distinctive feature of major depressive disorder.Therefore,DAPK1 may be related to cognitive dysfunction in major depressive disorder.In this study,we established a mouse model of major depressive disorder by housing mice individually and exposing them to chronic,mild,unpredictable stressors.We found that DAPK1 and tau protein levels were increased in the hippocampal CA3 area,and tau was hyperphosphorylated at Thr231,Ser262,and Ser396 in these mice.Furthermore,DAPK1 shifted from axonal expression to overexpression on the cell membrane.Exercise and treatment with the antidepressant drug citalopram decreased DAPK1 expression and tau protein phosphorylation in hippocampal tissue and improved both depressive symptoms and cognitive dysfunction.These results indicate that DAPK1 may be a potential reason and therapeutic target of cognitive dysfunction in major depressive disorder.

Kynurenine pathway of tryptophan metabolism in pathophysiology and therapy of major depressive disorder

Serotonin deficiency in major depressive disorder(MDD)has formed the basis of antidepressant drug development and was originally attributed to induction of the major tryptophan(Trp)-degrading enzyme,liver Trp 2,3-dioxygenase(TDO),by cortisol,leading to decreased Trp availability to the brain for serotonin synthesis.Subsequently,the serotonin deficiency was proposed to involve induction of the extrahepatic Trp-degrading enzyme indoleamine 2,3-dioxygenase(IDO)by proinflammatory cytokines,with inflammation being the underlying cause.Recent evidence,however,challenges this latter concept,as not all MDD patients are immune-activated and,when present,inflammation is mild and/or transient.A wide range of antidepressant drugs inhibit the activity of liver TDO and bind specifically to the enzyme,but not to IDO.IDO induction is not a major event in MDD,but,when it occurs,its metabolic consequences may be masked and overridden by upregulation of kynurenine monooxygenase(KMO),the gateway to production of modulators of immune and neuronal functions.KMO appears to be activated in MDD by certain proinflammatory cytokines and antidepressants with anti-inflammatory properties may block this activation.We demonstrate the ability of the antidepressant ketamine to dock(bind)to KMO.The pathophysiology of MDD may be underpinned by both the serotonin deficiency and glutamatergic activation mediated respectively by TDO induction and N-methyl-D-aspartate receptor activation.Inhibition of TDO and KMO should be the focus of MDD pharmacotherapy.

Major depressive disorder is correlated with the mitochondrial ND1 T3394C mutation in two Han Chinese families:Two case reports

BACKGROUND Major depressive disorder(MDD)is the most frequent reason of disabled people in the world,as reported by the World Health Organization.However,the diagnosis of MDD is mainly based on clinical symptoms.CASE SUMMARY The clinical,genetic,and molecular characteristics of two Chinese families with MDD are described in this study.There were variable ages of onset and severity in depression among the families.Both Chinese families had a very low prevalence of MDD.The mitochondrial genomes of these pedigrees were sequenced and indicated a homoplasmic T3394C(Y30H)mutation,with the polymorphism located at a highly conserved tyrosine at position 30 of ND1.The analysis also revealed unique sets of mitochondrial DNA(mtDNA)polymorphisms originating from haplogroups M9a3 and M9a.CONCLUSION This finding of the T3394C mutation in two unrelated depressed patients provides strong evidence that this mutation may have a part in the etiology of MDD.However,In these two Chinese families having the T3394C mutation,no functional mt DNA mutation was observed.Therefore,T3394C mutations are related with MDD,and the phenotypic manifestation of these mutations may be affected by changes in nuclear genes or environmental factors.

Identification and characterization of noncoding RNAs-associated competing endogenous RNA networks in major depressive disorder

BACKGROUND Major depressive disorder(MDD)is a common and serious mental illness.Many novel genes in MDD have been characterized by high-throughput methods such as microarrays or sequencing.Recently,noncoding RNAs(ncRNAs)were suggested to be involved in the complicated environmental-genetic regulatory network of MDD occurrence;however,the interplay among RNA species,including protein-coding RNAs and ncRNAs,in MDD remains unclear.AIM To investigate the RNA expression datasets downloaded from a public database and construct a network based on differentially expressed long noncoding RNA(lncRNAs),microRNAs(miRNAs),and mRNAs between MDD and controls.METHODS Gene expression data were searched in NCBI Gene Expression Omnibus using the search term“major depressive disorder.”Six array datasets from humans were related to the search term:GSE19738,GSE32280,GSE38206,GSE52790,GSE76826,and GSE81152.These datasets were processed for initial assessment and subjected to quality control and differential expression analysis.Differentially expressed lncRNAs,miRNAs,and mRNAs were determined,Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed,and protein-protein interaction network was generated.The results were analyzed for their association with MDD.RESULTS After analysis,3 miRNAs,12 lncRNAs,and 33 mRNAs were identified in the competing endogenous RNA network.Two of these miRNAs were earlier shown to be involved in psychiatric disorders,and differentially expressed mRNAs were found to be highly enriched in pathways related to neurogenesis and neuroplasticity as per Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses.The expression of hub gene fatty acid 2-hydroxylase was enriched,and the encoded protein was found to be involved in myelin formation,indicating that neurological development and signal transduction are involved in MDD pathogenesis.CONCLUSION The present study presents candidate nc RNAs involved in the neurogenesis and neuroplasticity pathways related to MDD.

Mechanism of Zuojin Pill in the treatment of anxiety disorder and Major depressive disorder based on network pharmacology and molecular docking validation

Background:Zuojin Pill(ZJP)is a classic Chinese herbal prescription with good efficacy in the treatment of Anxiety disorder(AD)and Major depressive disorder(MDD).Nevertheless,the potential mechanisms of ZJP remain unclear.Based on network pharmacology and molecular docking methods,this study aims to elucidate the possible mechanism of ZJP in the treatment of AD and MDD.Methods:The components and targets of Rhizoma Coptidis and Fructus Evodiae were collected from TCMSP,ETCM,HERB,SWISSADME and STITCH databases.The disease targets related to MDD and AD were collected from DISGENET,GENECARDS and OMIM databases.Protein-protein interaction network was constructed by STRING database,GO and KEGG enrichment analysis was performed by METASCAPE database,and“drugs-components-targets network”was constructed by Cytoscape software.Molecular docking verification was performed by Sailvina2.0 software.Results:ZJP may act on AKT1,IL6,TNF and other targets through caffeine,isorhamnetin,berberine and other components,regulating the Inflammatory mediator regulation of TRP channels,Serotonergic synapse,Dopaminergic synapse,PI3K/AKT signaling pathway,and other pathways.The results of molecular docking showed that berberine had the best binding activity with the core target.Conclusion:ZJP can exert anti-anxiety and anti-depression effects through multiple components,multiple targets and multiple pathways.

Abnormal activation of the occipital lobes during emotion picture processing in major depressive disorder patients

A large number of studies have demonstrated that depression patients have cognitive dysfunction. With recently developed brain functional imaging, studies have focused on changes in brain function to investigate cognitive changes. However, there is still controversy regarding abnormalities in brain functions or correlation between cognitive impairment and brain function changes. Thus, it is important to design an emotion-related task for research into brain function changes. We selected positive, neutral, and negative pictures from the International Affective Picture System. Patients with major depressive disorder were asked to judge emotion pictures. In addition, functional MRI was performed to synchronously record behavior data and imaging data. Results showed that the total correct rate for recognizing pictures was lower in patients compared with normal controls. Moreover, the consistency for recognizing pictures for depressed patients was worse than normal controls, and they frequently recognized positive pictures as negative pictures. The consistency for recognizing pictures was negatively correlated with the Hamilton Depression Rating Scale. Functional MRI suggested that the activation of some areas in the frontal lobe, temporal lobe, parietal lobe, limbic lobe, and cerebellum was enhanced, but that the activation of some areas in the frontal lobe, parietal lobe and occipital lobe was weakened while the patients were watching positive and neutral pictures compared with normal controls. The activation of some areas in the frontal lobe temporal lobe, parietal lobe, and limbic lobe was enhanced, but the activation of some areas in the occipital lobe were weakened while the patients were watching the negative pictures compared with normal controls. These findings indicate that patients with major depressive disorder have negative cognitive disorder and extensive brain dysfunction. Thus, reduced activation of the occipital lobe may be an initiating factor for cognitive disorder in depressed patients.

The norepinephrine transporter gene is associated with the retardation symptoms of major depressive disorder in the Han Chinese population

The norepinephrine transporter plays an important role in the pathophysiology and pharmacological treatment of major depressive disorder. Consequently, the norepinephrine transporter gene is an attractive candidate in major depressive disorder research. In the present study, we evaluated the depression symptoms of subjects with major depressive disorder, who were all from the North of China and of Hart Chinese origin, using the Hamilton Depression Scale. We examined the relationship between two single nucleotide polymorphisms in the norepinephrine transporter, rs2242446 and rs5569, and the retardation symptoms of major depressive disorder using quantitative trait testing with the UNPHASED program, rs5569 was associated with depressed mood, and the GG genotype may be a risk factor for this; rs2242446 was associated with work and interest, and the TT genotype may be a risk factor for loss of interest. Our findings suggest that rs2242446 and rs5569 in the norepinephrine transporter gene are associated with the retardation symptoms of depression in the Hart Chinese population.

Brain functional changes in facial expression recognition in patients with major depressive disorder before and after antidepressant treatment A functional magnetic resonance imaging study

Functional magnetic resonance imaging was used during emotion recognition to identify changes in functional brain activation in 21 first-episode, treatment-naive major depressive disorder patients before and after antidepressant treatment. Following escitalopram oxalate treatment, patients exhibited decreased activation in bilateral precentral gyrus, bilateral middle frontal gyrus, left middle temporal gyrus, bilateral postcentral gyrus, left cingulate and right parahippocampal gyrus, and increased activation in right superior frontal gyrus, bilateral superior parietal Iobule and left occipital gyrus during sad facial expression recognition. After antidepressant treatment, patients also exhibited decreased activation in the bilateral middle frontal gyrus, bilateral cingulate and right parahippocampal gyrus, and increased activation in the right inferior frontal gyrus, left fusiform gyrus and right precuneus during happy facial expression recognition. Our experimental findings indicate that the limbic-cortical network might be a key target region for antidepressant treatment in major depressive disorder.

Levomilnacipran and vortioxetine:Review of new pharmacotherapies for major depressive disorder

Major depressive disorder(MDD) is a common psychiatric disorder with an estimated lifetime prevalence rate in the range of 13% to 16% in the United States population. Patients with MDD often have symptoms such as depressed mood, loss of interest or pleasure in usual activities, changes in eating or sleeping patterns, fatigue, difficulty concentrating and thoughts of suicide. Although many pharmacotherapy treatment options are available for MDD, antidepressants can oftencause adverse effects that could affect adherence to the medication. Additionally, it is estimated that MDD is unremitting in 15% of patients and 35% can have recurrent episodes. Given the high rate of recurrence and the adverse effects associated with existing medications, new treatment options for depression are needed. Both levomilnacipran and vortioxetine are new antidepressants that were approved by the food and drug administration in 2013 for the treatment of MDD in adults. Levomilnacipran is a serotonin norepinephrine reuptake inhibitor that was effective in several short term studies and sustained efficacy and tolerability was demonstrated in a 48-wk extension study. Vortioxetine is a multi-modal antidepressant and it is thought to work via inhibition of the serotonin(5-HT) transporter, 5-HT3 A, 5-HT7 and 5-HT1 D antagonist, a 5-HT1 B partial agonist, and a 5-HT1 A agonist. Vortioxetine was effective in the treatment of MDD in both short-term trials as well as in the prevention of relapse in a 24-36 wk trial. Sustained efficacy and tolerability was demonstrated in several long-term open-label trials. Further studies comparing levomilnacipran and vortioxetine to other currently available antidepressants are needed to establish its place in therapy.

Increased myo-inositol in the posterior cingulate cortex in first-episode major depressive patients

Major depressive disorder (MDD) is a severe, disabling pathology characterized, in addition to affective, cognitive and motor symptoms, by self-focused attention and rumination. During recursive self-focused processes and rumination, the posterior cingulate cortex (PCC) is activated. In vivo proton magnetic resonance spectroscopy (MRS) is a noninvasive imaging technique that can directly assess living biochemistry in localized brain regions. The aim of this study, therefore, was to use 1H-MRS as a means of analyzing brain metabolites in the PCC of a group of first-episode, unmedicated MDD patients. PCC metabolite levels were analyzed at 3-T in a single voxel located bilaterally over the PCC in 7 patients diagnosed for the first time with MDD and with no previous pharmacological treatment, as well as in 9 control subjects. Differences in metabolite levels between groups were compared using independent t-tests. Myo-inositol was significantly higher, and NAA + NAAG/Cr significantly lower, in MDD patients than in controls. The other brain metabolites showed no statistical differences. The present results suggest that alterations in PCC metabolite levels are likely involved in MDD pathophysiology, and may help to improve our understanding of MDD and the role of the PCC in some symptoms of depression.

No association between a polymorphism of the adenylate cyclase type IX gene and major depressive disorder in the Chinese Han population

Previous studies have demonstrated that a missense single-nucleotide polymorphism variant （2316A〉G;rs2230739）of the adenylate cyclase type IX gene was associated with bipolar disorder and affective disorder.We determined genotype and allele frequencies using a ligase detection reaction method in 315 patients with major depressive disorder and 278 unrelated, sex-matched healthy control subjects.We did not detect any statistically significant differences in genotype and allele frequencies between patients and healthy control subjects.Furthermore,we found no significant difference between genders in major depressive disorder,nor between patients and controls in the same gender.These results suggest that 2316A〉G（rs2230739）may not be a risk factor for increasing susceptibility to major depressive disorder in the Chinese Han population.

Association of serotonin transporter gene polymorphisms and major depressive disorder in Chinese Han population

BACKGROUND： Serotonin transporter （5-HTT） polymorphisms comprise 5-HTT gene-linked polymorphism region （5-HTTLPR） and variable number of tandem repeats （VNTR）. Studies have revealed an association between 5-HTT polymorphism and major depressive disorder, which suggests that the ＂S＂ allele of 5-HTTLPR and Stin2.9 of 5-HTTVNTR are associated with major depressive disorder. However, there are a number of studies that do not support the 5-HTT polymorphism effect in major depressive disorder. OBJECTIVE： To study the relationship between 5-HTT gene polymorphism and major depressive disorder in Chinese Han population. DESIGN, TIME AND SETTING： Case-controlled study of 5-HTT gene polymorphism. The experiment was performed at the Central Laboratory, Third Affiliated Hospital of Sun Yat-sen University, China from March 2005 to January 2006. PARTICIPANTS： A total of 99 depressive patients of Chinese Han nationality were recruited for this study. All patients met DSM-IV diagnostic criteria for major depressive disorder and had a total score of Hamilton Depression Scale （24 items） ≥21 points. In addition, 101 healthy subjects, matched for age and gender, served as the control group. METHODS： Venous blood was collected from all subjects. 5-HTT genotypes and alleles were determined by polymerase chain reaction. Consistent with the Hardy-Weinberg equilibrium, the association between 5-HTT gene polymorphism and major depressive disorder were analyzed by Chi-square test. MAIN OUTCOME MEASURES： 5-HTTLPR and 5-HTTVNTR genotypes and allele frequencies were measured. RESULTS： No significant differences in 5-HTTLPR genotypes and allele frequencies were determined between patients and controls （P 〉 0.05）. However, significant differences in 5-HTTVNTR genotypes and allele frequencies were detected （P 〈 0.01 ）. The Stin2.10 allele and 10/10 genotype associated with major depressive disorder （OR = 2.61,7.7, P 〈 0.05; analysis of dose-response relationships Х^2 = 12.35, P 〈 0.01）. CONCLUSION： Results from the present study revealed no association between 5-HTTLPR and major depressive disorder. However, a significant association between 5-HTTVNTR and major depressive disorder existed in a population of Chinese Han. The presence of Stin2.10 and 10/10 genotypes increased the risk for major depressive disorder in a dose-dependent manner.