Serotonergic and BDNF genes and risk of depression after stroke

Innate immunity-mediated neuroinflammation promotes the onset and progression of post-stroke depression

Post-stroke depression (PSD) is a prevalent psychiatric disorder after stroke, with the incidence of approximately one-third among stroke survivors. It is classified as an organic mental disorder and has a well-documented association with stroke affecting various aspects of patients, such as the recovery of limb motor function, daily living self-care ability, and increasing the mortality of stroke survivors. However, the pathogenesis of PSD is not yet fully understood. Currently, immune inflammation is a research hotspot. This review focuses on the pathogenesis of PSD, particularly elucidating the role of inflammation in mediating neuroinflammation through innate immunity. Simultaneously, we highlight that peripheral inflammation following a stroke may trigger a detrimental cycle of neuroinflammation by activating innate immune pathways within the central nervous system, which could potentially contribute to the development of PSD. Lastly, we summarize potential treatments for PSD and propose targeting cytokines and innate immune pathways as novel therapeutic approaches.

Val/Met BDNF as a genetic risk for a false sense of security in post-discharge suicide risk

BACKGROUND

The time after discharge from psychiatric inpatient care is one of the most dangerous periods in terms of suicide risk. Predicting who is at higher risk could help with resource allocation to assure patients at high risk of suicide attempts are most closely followed. We previously showed that inpatients who improve their suicide ideation levels faster while in inpatient treatment are the ones with highest rates of post-discharge suicide. Here, we studied the possible genetic underpinnings associated with such risk.

METHOD

We recorded the slope of suicide ideation recovery of 710 psychiatric inpatients from which we studied two genetic variants likely associated with suicide risk: The serotonin transporter variant 5-HTTLPR, and the BDNF gene variant Val66Met.

RESULTS

We found that inpatients carrying the BDNF Met variant (hypothesized as conferring higher suicide risk) improved their suicide ideation scores faster than Val/Val carrying inpatients. No significant association was found for 5-HTTLPR.

LIMITATIONS

The present sample was genetically homogenous, and future research should replicate these findings on a more diverse sample.

CONCLUSIONS

In conclusion, we found a paradoxical result: Carrying the BDNF Met variant allows inpatients to improve faster, which was shown to confer higher risk at the post-discharge period. This may explain some inconsistencies in the literature in terms of the role of BDNF in suicide ideation and attempts.

Astrocytes in Post-Stroke Depression: Roles in Inflammation, Neurotransmission, and Neurotrophin Signaling

Post-stroke depression (PSD) is a frequent and disabling complication of stroke that affects up to one-third of stroke survivors. The pathophysiology of PSD involves multiple mechanisms, including neurochemical, neuroinflammatory, neurotrophic, and neuroplastic changes. Astrocytes are a type of glial cell that is plentiful and adaptable in the central nervous system. They play key roles in various mechanisms by modulating neurotransmission, inflammation, neurogenesis, and synaptic plasticity. This review summarizes the latest evidence of astrocyte involvement in PSD from human and animal studies, focusing on the alterations of astrocyte markers and functions in relation to monoamine neurotransmitters, inflammatory cytokines, brain-derived neurotrophic factor, and glutamate excitotoxicity. We also discuss the potential therapeutic implications of targeting astrocytes for PSD prevention and treatment. Astrocytes could be new candidates for antidepressant medications and other interventions that aim to restore astrocyte homeostasis and function in PSD. Astrocytes could be new candidates for antidepressant medications and other interventions that aim to restore astrocyte homeostasis and function in PSD.

An updated review on prediction and preventive treatment of post-stroke depression

INTRODUCTION

Post-stroke depression (PSD), one of the most common complications following stroke, affects approximately one-third of stroke patients and is significantly associated with increased disability and mortality as well as decreased quality of life, which makes it an important public health concern. Treatment of PSD significantly ameliorates depressive symptoms and improves the prognosis of stroke.

AREAS COVERED

The authors discuss the critical aspects of the clinical application of prediction and preventive treatment of PSD. Then, the authors update the biological factors associated with the onset of PSD. Furthermore, they summarize the recent progress in pharmacological preventive treatment in clinical trials and propose potential treatment targets. The authors also discuss the current roadblocks in the preventive treatment of PSD. Finally, the authors put postulate potential directions for future studies so as to discover accurate predictors and provide individualized preventive treatment.

EXPERT OPINION

Sorting out high-risk PSD patients using reliable predictors will greatly assist PSD management. Indeed, some predictors not only predict the incidence of PSD but also predict prognosis, which indicates that they might also aid the development of an individualized treatment scheme. Preventive application of antidepressants may also be considered.

Associations of vitamin D-related single nucleotide polymorphisms with post-stroke depression among ischemic stroke population

Objective

To investigate the relationship between single nucleotide polymorphisms (SNPs) related to vitamin D (VitD) metabolism and post-stroke depression (PSD) in patients with ischemic stroke.

Methods

A total of 210 patients with ischemic stroke were enrolled at the Department of Neurology in Xiangya Hospital, Central South University, from July 2019 to August 2021. SNPs in the VitD metabolic pathway (VDR, CYP2R1, CYP24A1, and CYP27B1) were genotyped using the SNPscan^™ multiplex SNP typing kit. Demographic and clinical data were collected using a standardized questionnaire. Multiple genetic models including dominant, recessive, and over-dominant models were utilized to analyze the associations between SNPs and PSD.

Results

In the dominant, recessive, and over-dominant models, no significant association was observed between the selected SNPs in the CYP24A1 and CYP2R1 genes and PSD. However, univariate and multivariate logistic regression analysis revealed that the CYP27B1 rs10877012 G/G genotype was associated with a decreased risk of PSD (OR: 0.41, 95% CI: 0.18-0.92, p = 0.030 and OR: 0.42, 95% CI: 0.18-0.98, p = 0.040, respectively). Furthermore, haplotype association analysis indicated that rs11568820-rs1544410-rs2228570-rs7975232-rs731236 CCGAA haplotype in the VDR gene was associated with a reduced risk of PSD (OR: 0.14, 95% CI: 0.03-0.65, p = 0.010), whereas no significant association was observed between haplotypes in the CYP2R1 and CYP24A1 genes and PSD.

Conclusion

Our findings suggest that the polymorphisms of VitD metabolic pathway genes VDR and CYP27B1 may be associated with PSD in patients with ischemic stroke.

Effects of Aloe-Emodin on the Expression of Brain Aquaporins and Secretion of Neurotrophic Factors in a Rat Model of Post-Stroke Depression

Post-stroke depression (PSD) is a common complication of stroke that can damage patients' brains. More and more studies have been conducted on PSD in recent years, but the exact mechanism is still not understood. Currently, animal models provide an alternative approach to better understand the pathophysiology of PSD and may also pave the way for the discovery of new treatments for depression. This study investigated the therapeutic effect and mechanism of aloe-emodin (AE) on PSD rats. Previous studies have shown that AE positively affects PSD in rats by improving depression, increasing their activities and curiosities, enhancing the number of neurons, and ameliorating damage to brain tissue. Meanwhile, AE could up-regulate the expression of brain-derived neurotrophic factor (BDNF) and neurotrophic 3 (NTF3), but it could also down-regulate the expression of aquaporins (AQP3, AQP4, and AQP5), glial fibrillary acidic protein (GFAP), and transient receptor potential vanilloid 4 (TRPV4), which is helpful in maintaining homeostasis and alleviating encephaledema. AE may be a prospective solution in the future for the treatment of PSD patients.

miR-34b-3p Inhibition of eIF4E Causes Post-stroke Depression in Adult Mice

Post-stroke depression (PSD) is a serious and common complication of stroke, which seriously affects the rehabilitation of stroke patients. To date, the pathogenesis of PSD is unclear and effective treatments remain unavailable. Here, we established a mouse model of PSD through photothrombosis-induced focal ischemia. By using a combination of brain imaging, transcriptome sequencing, and bioinformatics analysis, we found that the hippocampus of PSD mice had a significantly lower metabolic level than other brain regions. RNA sequencing revealed a significant reduction of miR34b-3p, which was expressed in hippocampal neurons and inhibited the translation of eukaryotic translation initiation factor 4E (eIF4E). Furthermore, silencing eIF4E inactivated microglia, inhibited neuroinflammation, and abolished the depression-like behaviors in PSD mice. Together, our data demonstrated that insufficient miR34b-3p after stroke cannot inhibit eIF4E translation, which causes PSD by the activation of microglia in the hippocampus. Therefore, miR34b-3p and eIF4E may serve as potential therapeutic targets for the treatment of PSD.

The Novel lncRNA ENST00000530525 Affects ANO1, Contributing to Blood-Brain Barrier Injury in Cultured hCMEC/D3 Cells Under OGD/R Conditions

Ischemic stroke (IS) is a major neurological disease with high fatality and residual disability burdens. Long noncoding RNAs (lncRNAs) have been found to play an important role in IS. However, the roles and significance of most lncRNAs in IS are still unknown. This study was performed to identify differentially expressed (DE) lncRNAs using a lncRNA microarray in whole blood samples of patients suffering from acute cerebral ischemia. Bioinformatics analyses, including GO, KEGG pathway enrichment analysis, and proximity to putative stroke risk location analysis were performed. The novel lncRNA, ENST00000530525, significantly decreased after IS. Furthermore, we evaluated lncRNA ENST00000530525 expression in cultured hCMEC/D3 cells under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions using fluorescent in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (RT-qPCR) analysis. To investigate the function of lncRNA ENST00000530525, its over-expression (OE) and negative control (NC) plasmids were transfected into hCMEC/D3 cells, and cell viability was detected by a cell counting kit-8 (CCK-8) assay after OGD/R. LncRNA ENST00000530525 and ANO1 expression were investigated using RT-qPCR and immunofluorescence. For blood-brain barrier (BBB) permeability, FITC-dextran transendothelial permeability assay and tight junction (TJ) protein immunofluorescence assays were performed. There were 3352 DE lncRNAs in the blood samples of acute IS patients. The validation results were consistent with the gene chip data. The GO and KEGG results showed that these lncRNAs were mainly related to oxygen and glucose metabolism, leukocyte transendothelial migration, mitophagy and cellular senescence. Among these, lncRNA ENST00000530525 was the most highly downregulated lncRNA and it was mapped within the IS-associated gene anoctamin-1 (ANO1). We further found that lncRNA ENST00000530525 was downregulated in hCMEC/D3 cells under 4 h OGD and 20 h reoxygenation (OGD4/R20) conditions. Upregulating lncRNA ENST00000530525 by plasmid transfection decreased cell viability while increasing ANO1 expression and it contributed to BBB injury in hCMEC/D3 cells after OGD4/R20. The lncRNA ENST00000530525 might play deleterious roles in post-stroke pathogenesis. These results show that some DE lncRNAs in humans participate through characteristic roles in post-stroke pathogenesis; thus, the roles and significance of some novel lncRNAs in IS warrant further study.

Ischemic Stroke and Sleep: The Linking Genetic Factors

This review summarizes the available data about genetic factors which can link ischemic stroke and sleep. Sleep patterns (subjective and objective measures) are characterized by heritability and comprise up to 38-46%. According to Mendelian randomization analysis, genetic liability for short sleep duration and frequent insomnia symptoms is associated with ischemic stroke (predominantly of large artery subtype). The potential genetic links include variants of circadian genes, genes encoding components of neurotransmitter systems, common cardiovascular risk factors, as well as specific genetic factors related to certain sleep disorders.

G-Protein-Coupled Receptors and Ischemic Stroke: a Focus on Molecular Function and Therapeutic Potential

In ischemic stroke, there is only one approved drug, tissue plasminogen activator, to be used in clinical conditions for thrombolysis. New neuroprotective therapies for ischemic stroke are desperately needed. Several targets and pathways have been shown to confer neuroprotective effects in ischemic stroke. G-protein-coupled receptors (GPCRs) are one of the most frequently targeted receptors for developing novel therapeutics for central nervous system disorders. GPCRs are a large family of cell surface receptors that response to a wide variety of extracellular stimuli. GPCRs are involved in a wide range of physiological and pathological processes. More than 90% of the identified non-sensory GPCRs are expressed in the brain, where they play important roles in regulating mood, pain, vision, immune responses, cognition, and synaptic transmission. There is also good evidence that GPCRs are implicated in the pathogenesis of stroke. This review narrates the pathophysiological role and possible targeted therapy of GPCRs in ischemic stroke.

Association Study of SLC6A4 (5-HTTLPR) Polymorphism and Its Promoter Methylation with Rehabilitation Outcome in Patients with Subacute Stroke

Recently it has been suggested that serotonin transporter (SLC6A4) and its 5HTTLPR polymorphism could be involved in post stroke recovery. Here, we characterized the methylation profile of two different CpG islands within the SLC6A4 promoter region in the whole blood of 50 patients with subacute stroke before and after a six-week rehabilitation treatment. These patients were genotyped for 5HTTLPR polymorphism identifying patients on the basis of short (S) and L (L) alleles: 17 patients LL, 22 patients LS and 11 patients SS. At baseline, all CpG sites for both CpG islands displayed a heterogeneous methylation percentage that were not influenced by the different genotypes. After rehabilitation, we found a significant variation in the methylation levels (increase/decrease) in the specific CpG sites of both CpG islands. The statistical analysis showed a significant relationship between the LL, LS and SS alleles and the outcome of the rehabilitation intervention (χ² (2,50) = 6.395, p = 0.041). Specifically, we found a significant difference between patients with or without a favorable outcome in the LL (11.1% with a favorable outcome) and in the SS (54.4% with a favorable outcome) groups. Our data suggest that 5-HTTLPR polymorphisms and SLC6A4 promoter methylation may be employed as a non-invasive biological marker of recovery in patients with stroke undergoing rehabilitation.

Association between BDNF Polymorphism and Depressive Symptoms in Patients Newly Diagnosed with Type 2 Diabetes Mellitus

PURPOSE

Little is known about the relationship between brain-derived neurotrophic factor (BDNF) gene polymorphisms and psychiatric symptoms in diabetes patients. We investigated the effects of BDNF Val/66/Met polymorphism, glucose status, psychological susceptibility, and resilience on anxiety and depression symptoms in patients newly diagnosed with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We examined biochemical factors and BDNF polymorphism in 89 patients who were newly diagnosed with T2DM. Psychiatric symptoms were investigated with the Hospital Anxiety and Depression Scale (HADS), and the Connor-Davidson Resilience Scale (CD-RISC) and Impact of Event Scale (IES) were used to assess psychological resilience and susceptibility to psychological distress, respectively. Logistic regression analyses were conducted to investigate factors associated with psychiatric symptoms.

RESULTS

We determined that 62 patients (70%) were Met-carriers. No significant differences were found between the Val/Val homozygous and Met-carrier groups regarding age, sex, body mass index, and clinical factors related to glycemic control and lipid profiles. HADS-anxiety and HADS-depression scores and IES factor scores were higher in the Met-carrier than the Val/Val homozygous group. Hemoglobin A1c (HbA1c) level was significantly inversely correlated with the severity of depressive symptoms. Resilience factors showed significant inverse correlations, and IES factors showed positive correlations with depressive symptom severity. In the logistic regression analysis model, depressive symptoms were significantly associated with HbA1c and BDNF polymorphism, whereas only the hyperarousal factor of the IES scale was associated with anxiety.

CONCLUSION

Depressive symptoms are associated with the presence of the Met-carriers and lower HbA1c in patients newly diagnosed with T2DM.

The Role of Tet2-mediated Hydroxymethylation in Poststroke Depression

Poststroke depression (PSD) is a common complication of stroke and has long been a serious threat to human health. PSD greatly affects neurological recovery, quality of life and mortality. Recent studies have shown that 5-hydroxymethylcytosine (5hmC), an important epigenetic modification, is enriched in the brain and associated with many neurological diseases. However, its role in PSD is still unclear. In this study, middle cerebral artery occlusion (MCAO) and spatial restraint stress were used to successfully induce a PSD mouse model and resulted in reduced 5hmC levels, which were caused by Tet2. Furthermore, genome-wide analysis of 5hmC revealed that differentially hydroxymethylated regions (DhMRs) were associated with PSD. DhMRs were enriched among genes involved in the Wnt signaling pathway, neuron development and learning or memory. In particular,DhMRs were strongly enriched in genes with lymphoid enhancer factor 1 (LEF1) binding motifs. Finally, we demonstrated that decreases in TET2 expression in the brain caused PSD by decreasing Wnt/β-catenin/LEF1 pathway signaling to promote inflammatory factor IL-18 expression. In conclusion, our data highlight the potential for 5hmC modification as a therapeutic target for PSD.

Association of SLC6A4 methylation with long-term outcomes after stroke: focus on the interaction with suicidal ideation

Serotonin (5-HT) plays an important role in cerebrovascular homeostasis and psychiatric disorders, including suicidality. Methylation of the serotonin transporter gene (SLC6A4) is associated with 5-HT expression. However, the prognostic roles of SLC6A4 methylation and suicidal ideation (SI) in long-term outcomes of stroke have not been evaluated. We investigated the independent and interactive effects of SLC6A4 methylation and SI immediately after stroke on long-term outcomes. Blood SLC6A4 methylation status and SI based on the suicide item of the Montgomery–Åsberg Depression Rating Scale were assessed in 278 patients at 2 weeks after stroke. After the index stroke, cerebro-cardiovascular events by SLC6A4 methylation status and SI were investigated over an 8–14-year follow-up period and using Cox regression models adjusted for a range of covariates. SLC6A4 hypermethylation and SI within 2 weeks of stroke both predicted worse long-term outcomes, independent of covariates. A significant interaction effect of SI and the methylation status of CpG 4 on long-term stroke outcomes was also identified. The association between SLC6A4 methylation and long-term adverse outcomes may be strengthened in the presence of SI within 2 weeks after stroke. Evaluation of methylation and SI status during the acute phase can be helpful when assessing stroke patients.

Pro-inflammatory cytokines are associated with the development of post-stroke depression in the acute stage of stroke: A meta-analysis

Background: Pro-inflammatory cytokines may be associated with post-stroke depression (PSD); however, results from different studies are inconsistent.Objectives: To investigate whether pro-inflammatory cytokines are associated with the development of PSD in acute stroke.Methods: PubMed, Embase, and Web of science were searched for relevant literature. Meta-analyzes were performed to determine whether the baseline blood concentrations of pro-inflammatory cytokines differed between acute stroke patients with and without depression. Sensitivity analyzes and regression analyzes were conducted to explore sources of heterogeneity.Results: We included 889 acute stroke patients from eight original studies, 312 of whom developed PSD and 577 did not. The serum concentrations of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were higher in the PSD group, compared with the non-PSD group (IL-6: SMD = 1.26, 95% CI = [0.55, 1.97], P < 0.001; TNF-α: SMD = 0.61, 95% CI = [0.13, 1.10], P = 0.010).Conclusions: This study indicates IL-6 and TNF-α as potential biomarkers of PSD in the acute stage of stroke and provides theoretical support for the early prevention and treatment of PSD.

Investigating the Contribution of NPSR1, IL-6 and BDNF Polymorphisms to Depressive and Anxiety Symptoms in Hemodialysis Patients

AIMS

Psychological symptoms are prevalent in hemodialysis (HD) patients. Previous investigations showed that brain-derived neurotrophic factor (BDNF) and interleukin-6 (IL-6) as well as the interaction with neuropeptide S receptor 1 (NPSR1) are linked to the development of psychological distress. This study examined the association of polymorphisms of genes encoding these proteins with depression and anxiety in a representative group of Jordanian HD patients.

METHODS

A total of 302 HD patients were involved in the study and categorized into three groups based on the Hospital Anxiety and Depression Scale, HADS-D or HADS-A scores as follows: normal (<7), mild (8-10) and moderate-severe (11-21). Single nucleotide polymorphism (SNP) of NPSR1 Asn107Ile (rs324981), IL-6 G174C (rs1800795), and BDNF Val66Met (rs6265) was genotyped using blood samples.

RESULTS

The frequency of Ile-allele of NPSR1 Asn107Ile was significantly higher in patients with moderate-severe HADS-A scores versus normal (53% vs. 40.8%, p = .035). Using ordinal regression analysis, Asn-allele of NPSR1 polymorphism was nominally significantly associated with a lower risk of anxiety (OR = 0.57, CI: 0.33-0.97, p = .038) after adjusting for other covariates. A marginally significant difference in genotype distribution of IL-6 G174C was observed among patients according to HADS-D scores (p = .05). Furthermore, carriers of IL-6174 CC genotype showed lower median IL-6 serum concentration versus carriers of GG genotype (5.2 vs. 1.35 pg/mL, p < .05).

CONCLUSIONS

The results support the genetic role of NPSR1 in the pathogenesis of anxiety and suggest that carriers of NPSR1 Ile-allele are at increased risk of anxiety in HD patients. Neither BDNF Val66Met nor IL-6 G174C were linked to psychological symptoms. Future studies among other ethnicities are necessary to verify the observations.

Novel susceptibility genes were found in a targeted sequencing of stroke patients with or without depression in the Chinese Han population

BACKGROUND

Both stroke and depression are multi-factorial diseases, with both genetic and environmental factors likely to participate in their pathogenesis. Post stroke depression (PSD) is a common complication after stroke leading to poor functional outcome, increased physical disability and mortality. Although several genes have been associated with PSD, the genetic basis of PSD remains poorly understood.

METHOD

A 2-stage candidate gene study by targeted sequencing was conducted involving stroke patients with or without depression and health controls. In the discovery stage (121 PSD, 131 non-PSD and 639 HC), logistic regression was used to test associations respectively in PSD and non-PSD groups. In the replication stage (200 PSD, 218 non-PSD and 983 HC), 54 selected SNPs were again genotyped in an independent cohort. Fixed-effects inverse variance-weighted meta-analysis was used in the combined samples.

RESULTS

The study identified 2 novel genes associated with PSD [HTR3D (rs55674402, p = 0.002512, odds ratio (OR) = 0.7431); NEUROG3 (rs144643855, p = 0.00325, OR = 0.6523)] and 3 risk SNPs in one risk gene associated with non-PSD [PIK3C2B (rs17406271, p = 0.0006801, OR = 1.446; rs2271419, p = 0.0005836, OR = 1.497; rs2271420, p = 0.001031, OR = 1.431)] in the Chinese sample. NEUROG3 shows highest expression level in hippocampus. Functional enrichment analysis shows that susceptibility genes for PSD are mostly enriched in chemical synaptic transmission and regulation of lipid synthetic process.

LIMITATIONS

The sample size was not sufficient to reach a genome-wide p value level. To overcome this shortage, some unique strategies were applied during the selection of SNPs for replication. Secondly, the age, gender composition and depressive severity between two stages were not well-matched. Different sample sources should be blamed, and to minimizing the influence, gender was corrected as co-variant in logistic regression.

CONCLUSION

This study identified that HTR3D and NEUROG3 were linked with the susceptibility of PSD and PIK3C2B with stroke in the Chinese Han population. Further replication of these findings in a larger and better matched sample is warranted. Functional analysis suggests that the pathogenesis of PSD may be implicated in 5-HT synaptic transmission, neural plasticity and lipid metabolism, and therapeutic interventions targeting these pathways may be effective approaches for PSD treatment.

Shared genetic risk factors for depression and stroke

BACKGROUND

The comorbidity of major depressive disorder (MDD) and stroke are common in clinic. There is a growing body of evidence suggesting a bi-directional relationship between stroke and depression. However, the mechanisms underlying the relationship between MDD and stroke are poorly investigated. Considering that both MDD and stroke can be heritable and are influenced by multiple risk genes, shared genetic risk factors between MDD and stroke may exist.

OBJECTIVE

The objective is to review the existing evidence for common genetic risk factors for both MDD and stroke and to outline the possible pathophysiological mechanisms mediating this association.

METHODS

A systematic review and meta-analysis was performed. Gene association studies regarding stroke and depression were searched in the database PubMed, CNKI, and Chinese Biomedical Literature Database before December 2018. Statistical analysis was performed using the software Revman 5.3.

RESULTS

Genetic polymorphisms of 4 genes, methylenetetrahydrofolate reductase (MTHFR) and apolipoprotein E (ApoE) have been demonstrated to associate with the increased risk for both MDD and stroke, while the association between identified polymorphisms in angiotensin converting enzyme (ACE) and serum paraoxonase (PON1) with depression is still under debate, for the existing studies are insufficient in sample size. These results suggest the possible pathophysiological mechanisms that are common to these two disorders, including immune-inflammatory imbalance, increased oxidative and nitrative stress, dysregulation of lipoprotein and lipid metabolism, and changes of cerebrovascular morphology and function. Other associated genes with few or conflicting results have also been included, and a few studies have investigated the effects of the described polymorphisms on MDD and stroke comorbidity, such as post stroke depression.

CONCLUSION

These findings suggest that shared genetic pathways may contribute to the comorbidity of MDD and stroke. Studies to evaluate the shared genetic variations between MDD and stroke may provide insights into the molecular mechanisms that trigger disease progression.

Associations of white matter hyperintensities with poststroke depression: A 1-year longitudinal study

BACKGROUND

Depression is common in stroke survivors and may lead to a poor prognosis and more severe functional impairment. Although subcortical white matter hyperintensities (WMHs) are associated with late-life depression, few studies have examined the association between depression and WMHs after a stroke. We investigated the associations of periventricular (PVWMH) and deep (DWMH) WMHs with poststroke depression (PSD) at two time points after stroke.

METHODS

A total of 408 patients were evaluated 2 weeks after stroke (baseline), and of those, 284 (70%) were followed up 1 year later. Magnetic resonance images were obtained in all subjects at baseline. PVWMHs and DWMHs were rated using the four-point modified Fazekas scale and categorized as mild (grades 0 and 1) or severe (grades 2 and 3). Depression was diagnosed according to DSM-IV criteria, and subjects were divided into without PSD, any PSD, and major PSD groups at baseline, and follow-up examinations were conducted according to the severity of depression. Associations of PSD with PVWMHs and DWMHs were assessed using multivariate logistic regression analyses after adjusting for various demographic and clinical characteristics.

RESULTS

The adjusted analyses revealed that severe PVWMHs were significantly associated with any PSD at baseline and severe DWMHs were significantly associated with major PSD at follow-up.

CONCLUSION

The association between WMH and PSD varies according to type of WMH, and time after stroke, such that early depressive symptoms are associated with PVWMHs, and delayed severe depression is associated with DWMHs.

Haplotype Analysis on the Relationship of the DNAJC6 Gene with Early-Onset Parkinson's Disease Risk in a Chinese Population

BACKGROUND

DNAJC6 gene is one of the Parkinson's disease (PD) related genes, but relationship between DNAJC6 polymorphisms and PD remains unclear.

OBJECTIVE

We aims to examine the association between genetic variations in DNAJC6 gene and idiopathic early-onset PD (EOPD) in the Chinese population.

METHODS

Exons and intron/exon boundaries of DNAJC6 gene was amplified and sequenced in 135 EOPD patients and 212 healthy controls. Single nucleotide polymorphisms (SNP)-based and haplotype-based association study between EOPD and DNAJC6 was conducted. SNP-SNP interactions were investigated using the generalized multifactor dimensionality reduction (GMDR) method. We further evaluated the effect of variants on gene function and expression using online in silico algorithms and databases.

RESULTS

We found fourteen previously reported SNPs in the DNAJC6 gene. The frequencies of variant alleles in rs11208644, rs4582839 and rs4915691 were observed significantly higher in EOPD group compared to healthy controls, while in rs6588144 was significantly lower. Additionally, haplotype analysis indicated that the CTCACTCGGC, CTTACTCGGC and TTTGTTCGAC haplotypes were associated with higher EOPD risk in EOPD patients. SNP-SNP interaction analysis showed that rs12077111-rs4592284 SNP combination was the best model with higher EOPD risk. Based on the in silico analysis results, these SNPs were predicted to be no harm to the protein function, but might lead to possible changes in splice site and alter the expression level of DNAJC6.

CONCLUSION

Our study indicated that EOPD was associated with several SNPs and haplotypes of DNAJC6 gene.

Poststroke Depression Biomarkers: A Narrative Review

Poststroke depression (PSD) is the most prevalent psychiatric disorder after stroke, which is independently correlated with negative clinical outcome. The identification of specific biomarkers could help to increase the sensitivity of PSD diagnosis and elucidate its pathophysiological mechanisms. The aim of current study was to review and summarize literature exploring potential biomarkers for PSD diagnosis. The PubMed database was searched for papers published in English from October 1977 to December 2017, 90 of which met inclusion criteria for clinical studies related to PSD biomarkers. PSD biomarkers were subdivided into neuroimaging, molecular, and neurophysiological. Some of them could be recommended to support PSD diagnosing. According to the data, lesions affecting the frontal-subcortical circles of mood regulation (prefrontal cortex, basal nuclei, and thalamus) predominantly in the left hemisphere can be considered as neuroimaging markers and predictors for PSD for at least 1 year after stroke. Additional pontine and lobar cerebral microbleeds in acute stroke patients, as well as severe microvascular lesions of the brain, increase the likelihood of PSD. The following molecular candidates can help to differentiate PSD patients from non-depressed stroke subjects: decreased serum BDNF concentrations; increased early markers of inflammation (high-sensitivity C-reactive protein, ferritin, neopterin, and glutamate), serum pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-18, IFN-γ), as well as pro-inflammatory/anti-inflammatory ratios (TNF-α/IL-10, IL-1β/IL-10, IL-6/IL-10, IL-18/IL-10, IFN-γ/IL-10); lowered complement expression; decreased serum vitamin D levels; hypercortisolemia and blunted cortisol awakening response; S/S 5-HTTLPR, STin2 9/12, and 12/12 genotypes of the serotonin transporter gene SLC6A4, 5-HTR2a 1438 A/A, and BDNF met/met genotypes; higher SLC6A4 promoter and BDNF promoter methylation status. Neurophysiological markers of PSD, that reflect a violation of perception and cognitive processing, are the elongation of the latency of N200, P300, and N400, as well as the decrease in the P300 and N400 amplitude of the event-related potentials. The selected panel of biomarkers may be useful for paraclinical underpinning of PSD diagnosis, clarifying various aspects of its multifactorial pathogenesis, optimizing therapeutic interventions, and assessing treatment effectiveness.

Clinical practice guidelines for post-stroke depression in China

Post-stroke depression (PSD) is a very common complication that leads to increased physical disability, poor functional outcome, and higher mortality. Therefore, early detection and treatment are very important. Since there are currently no specific guidelines for this disorder in China, the purpose of this study was to develop PSD guidelines and provide suggestions for clinicians and related workers.

Longitudinal Impact of Depression on Quality of Life in Stroke Patients

OBJECTIVE

Stroke is associated with significant long-term morbidity and poor quality of life (QOL). Depression is one of the most common complications after stroke and has been associated with QOL cross-sectionally. We investigated the longitudinal impact of depression in the acute phase of stroke on QOL 1 year after stroke.

METHODS

In total, 423 patients were evaluated 2 weeks after stroke, and 288 (68%) were followed 1 year later. QOL was assessed using the World Health Organization Quality of Life-Abbreviated form (WHOQOL-BREF) at baseline and follow-up. Depression was diagnosed according to Diagnostic and Statistical Manual of Mental Disorders-IV criteria; demographic and clinical characteristics data, including stroke severity, were obtained at baseline. The longitudinal associations of post-stroke depression (PSD) at baseline with QOL across two evaluation points were assessed using a repeated-measures analysis of variance.

RESULTS

The WHOQOL-BREF scores were significantly and persistently lower 1 year after stroke in patients with PSD at baseline compared with those without PSD at baseline independent of demographic and clinical characteristics, including stroke severity.

CONCLUSION

PSD in the acute phase of stroke is an independent predictor of QOL in both the acute and chronic phases of stroke. Our findings underscore the importance of evaluating depression in the acute phase of stroke.

Relationship between Occupational Stress, 5-HT2A Receptor Polymorphisms and Mental Health in Petroleum Workers in the Xinjiang Arid Desert: A Cross-Sectional Study

At present, there is growing interest in research examining the relationship between occupational stress and mental health. Owing to the socioeconomic impact of occupational stress and the unique environment of petroleum workers in Xinjiang, a cross-sectional study was carried out between April and December 2015 to investigate the relationship between occupational stress, 5-hydroxytryptamine receptor (5-HTR2A) genotype, and mental health. A total of 1485 workers were selected. The Symptom Checklist 90 was used to assess nine classes of psychological symptoms. Work-related stressors were evaluated using the Occupational Stress Inventory-Revised Edition. Levels of 5-HTR2A (the Tl02C and A-1438G single nucleotide polymorphism in the 5-HTR2A gene) were measured by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The findings of the present study revealed a high prevalence rate of mental health problems (40.29%) in petroleum workers stationed in the arid desert, and suggested a strong correlation between occupational stress and mental health. The TC and CC genotype of Tl02C were found to be protective factors against mental health problems (odds ratio (OR) = 0.455, 95% confidence interval (CI): = 0.269–0.771, odds ratio (OR) = 0.340, 95% confidence interval (CI): 0.162–0.716). AG and GG genotype of A-1438G [odds ratio (OR) 1 = 2.729, 95% confidence interval (CI): 1.433–5.195; odds ratio (OR) 2 = 2.480, 95% confidence interval (CI): 1.221–5.037] were revealed as risk factors. These data provide evidence that occupational stress and 5-HTR2A gene polymorphism contributes to the incidence of mental health problems.

Determinants and escitalopram treatment effects on suicidal ideation in patients with acute coronary syndrome: Findings from the K-DEPACS and EsDEPACS studies

BACKGROUND

This study is aimed to investigate the determinants of suicidal ideation as well as to assess escitalopram treatment effects on suicidal ideation in patients with acute coronary syndrome (ACS).

METHODS

A total of 1152 patients were consecutively recruited at baseline, 2 to 14weeks after a confirmed ACS episode. Of 446 baseline participants with comorbid depressive disorders, 300 were randomized to a 24-week double-blind trial of escitalopram or placebo treatment. Suicidal ideation was determined using the "suicidal thoughts" item of the Montgomery and Asberg Depression Rating Scale. Socio-demographic and clinical characteristics, including depressive and anxiety symptoms, cardiovascular risk factors, and current cardiac status, were assessed.

RESULTS

Suicidal ideation was independently associated with past history of depression, depressive and anxiety disorders, and higher troponin I levels. Escitalopram treatment was significantly more efficacious in reducing and treating suicidal ideation than placebo treatment over a 24-week period. These effects were largely explained by remission status of depressive and anxiety disorders.

CONCLUSIONS

Suicidal ideation is associated with unfavorable psychiatric and ACS status during the acute phase of ACS. Successful treatment of depression and anxiety with escitalopram had significant beneficial effects on suicidal ideation in these patients.

Serotonergic genes and depressive disorder in acute coronary syndrome: The Korean depression in ACS (K-DEPACS) study

Genes coding for the serotonergic pathway have been associated with depressive disorders. However, these associations have rarely been tested in acute coronary syndrome (ACS) patients vulnerable to depression. This study aimed to investigate whether polymorphisms of serotonin transporter (5-HTT) and serotonin 2a receptor (5-HTR2a) genes are associated with occurrence of depressive disorder in ACS. 969 patients with recently developed ACS were recruited at baseline, and 711 were followed 1 year thereafter. Depressive disorder was diagnosed according to DSM-IV criteria, and analysed as an outcome at baseline (prevalence), and follow up (incidence and persistence). Genotypes were ascertained for 5-HTTLPR, STin2 VNTR, 5-HTR2a 102T/C, and 5-HTR2a 1438A/G. Logistic regression models were used to investigate associations. The 5-HTTLPR s/s genotype was independently associated with depressive disorder prevalence and persistence following ACS, but no significant associations were found with the other polymorphisms. ACS patients with the 5-HTTLPR s allele are thus potentially susceptible to depressive disorder in the early phase after ACS, and with its persistence over the subsequent year.

Serum Levels of High-sensitivity C-Reactive Protein at Admission Are More Strongly Associated with Poststroke Depression in Acute Ischemic Stroke than Homocysteine Levels

Inflammatory processes have fundamental roles in depression. The primary purpose of this study was to assess the serum levels of high-sensitivity C-reactive protein (Hs-CRP) and homocysteine (HCY) at admission to the presence of poststroke depression (PSD). From December 2012 to December 2013, first-ever acute ischemic stroke patients who were admitted to the hospital within the first 24 h after stroke onset were consecutively recruited and followed up for 6 months. Serum levels of Hs-CRP and HCY were tested at admission. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for depression at 6 months after stroke. Ninety-five patients (42.0%) showed depression (major + minor) at 6 months after admission, and in 69 patients (30.5%), this depression was classified as major. In the 69 patients with major depression, our results showed significantly higher Hs-CRP and HCY levels at admission than patients without major depression. After adjusting all other possible covariates, Hs-CRP and HCY still were independent predicators of PSD with adjusted OR of 1.332 (95% CI, 1.230-1.452; P < 0.001) and 1.138 (95% CI, 1.072-1.274; P < 0.001), respectively. The area under the receiver operating characteristic curve values of Hs-CRP and HCY were 0.765 (95% CI, 0.701-0.9825) and 0.684 (95% CI, 0.610-0.757) for PSD, respectively. The prognostic accuracy of combined model (HCY and Hs-CRP) was higher compared to those biomarkers alone and other markers. Elevated serum levels of Hs-CRP and HCY at admission were found to be associated with depression 6 months after stroke, suggesting that these alterations might participate in the pathophysiology of depression symptoms in stroke patients.

Comorbidity of depression with physical disorders: research and clinical implications

Depression is prevalent in patients with physical disorders, particularly in those with severe disorders such as cancer, stroke, and acute coronary syndrome. Depression has an adverse impact on the courses of these diseases that includes poor quality of life, more functional impairments, and a higher mortality rate. Patients with physical disorders are at higher risk of depression. This is particularly true for patients with genetic and epigenetic predictors, environmental vulnerabilities such as past depression, higher disability, and stressful life events. Such patients should be monitored closely. To appropriately manage depression in these patients, comprehensive and integrative care that includes antidepressant treatment (with considerations for adverse effects and drug interactions), treatment of the physical disorder, and collaborative care that consists of disease education, cognitive reframing, and modification of coping style should be provided. The objective of the present review was to present and summarize the prevalence, risk factors, clinical correlates, current pathophysiological aspects including genetics, and treatments for depression comorbid with physical disorders. In particular, we tried to focus on severe physical disorders with high mortality rates, such as cancer, stroke, and acute coronary syndrome, which are highly comorbid with depression. This review will enhance our current understanding of the association between depression and serious medical conditions, which will allow clinicians to develop more advanced and personalized treatment options for these patients in routine clinical practice.

Serotonin Transporter Gene 5-HTTLPR Polymorphism as a Protective Factor Against the Progression of Post-Stroke Depression

Polymorphisms in the 5-HTT and BDNF genes are shown to affect their function at the molecular and serum level. Prior work has tried to correlate the polymorphisms with post-stroke depression (PSD), the results nevertheless remain indefinitive. A plausible reason accounting for the uncertainty relates to the small sample of each published trial. In this study, we have performed a comprehensive meta-analysis in order to evaluate the effects of 5-HTT and BDNF polymorphisms (5-HTTLPR, STin2 VNTR, 5-HTR2a 102 T/C, Val66Met) on genetic risk of PSD. Human case-control trials were identified by computer-assisted and manual searches. The article search was performed until October 2014. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the fixed effects meta-analysis to measure the effects 5-HTT and BDNF polymorphisms exerted on PSD. We also performed test of heterogeneity, test of publication bias, and sensitivity analysis to examine the reliability and stability of combined effects. 5-HTTLPR was clearly associated with genetic risk of PSD. The association seemed to be more pronounced in the homozygous model (OR = 0.34, 95% CI = 0.23-0.51, P(Q-test) = 0.63). Both the heterozygous model and the recessive model showed 50% decreased risk of PSD (OR = 0.50, 95% CI = 0.37-0.67, P(Q-test) = 0.91; OR = 0.50, 95% CI = 0.36-0.70, P(Q-test) = 0.43, respectively). Such significant association was also detected for Caucasian and Asian. These results were reliable and stable based on related analyses. Taken together, 5-HTTLPR polymorphism of the 5-HTT gene seems to protect against the occurrence of PSD. Small sample size for the polymorphisms within 5-HTT and BDNF genes may have caused underestimated associations, and a larger study is required to further assess the relations.

Serial treatments of primed low-frequency rTMS in stroke: characteristics of responders vs. nonresponders

PURPOSE

This study analyzed the characteristics of responders vs. nonresponders in people with stroke receiving a novel form of repetitive transcranial magnetic stimulation (rTMS) to improve hand function.

METHODS

Twelve people with stroke received five treatments of 6-Hz primed low-frequency rTMS to the contralesional primary motor area. We compared demographic factors, clinical features, and the ipsilesional/contralesional volume ratio of selected brain regions in those who improved hand performance (N = 7) on the single-hand component of the Test Évaluant la performance des Membres supérieurs des Personnes Âgées (TEMPA) and those who showed no improvement (N = 5).

RESULTS

Responders showed significantly greater baseline paretic hand function on the TEMPA, greater preservation volume of the ipsilesional posterior limb of the internal capsule (PLIC), and lower scores (i.e., less depression) on the Beck Depression Inventory than nonresponders. There were no differences in age, sex, stroke duration, paretic side, stroke hemisphere, baseline resting motor threshold for ipsilesional primary motor area (M1), NIH Stroke Scale, Upper Extremity Fugl-Meyer, Mini-Mental State Examination, or preservation volume of M1, primary somatosensory area, premotor cortex, or supplementary motor area.

CONCLUSION

Our results support that preserved PLIC volume is an important influential factor affecting responsiveness to rTMS.

Association of HTR2A T102C and A-1438G polymorphisms with susceptibility to major depressive disorder: a meta-analysis

Serotonin 2A receptor (HTR2A) gene was implicated to be associated with major depressive disorder (MDD) susceptibility due to its role of key neurotransmitter in many physiologic processes. A great number of related studies reported in different populations have emerged. The results of these studies, however, have been inconsistent and thereby definite conclusions are difficult to establish. With the cumulative data in recent years, it was necessary to carry out a comprehensive analysis of previous findings. Electronic databases were systematically searched for studies published before May 2013. Pooled odds ratios (OR) and 95 % confidence interval (CI) were estimated under three different genetic models. Subgroup and sensitivity analyses were also performed. A total of 21 studies, 3,299 patients and 4,092 controls, met the selection criteria. 15 studies included HTR2A T102C polymorphism (with a total of 2,409 patients and 3,130 controls), and 9 studies included HTR2A A-1438G polymorphism (with a total of 1,510 patients and 2,281 controls). Our results showed that no significant association of MDD susceptibility with T102C polymorphism was found in allelic analysis and genotypic analysis (For T vs. C: OR = 1.06, 95 % CI = 0.95-1.18, P = 0.307; For TT + TC vs. CC: OR = 1.07, 95 % CI = 0.90-1.28, P = 0.451; For TT vs. TC + CC: OR = 1.08, 95 % CI = 0.95-1.22, P = 0.235). With respect to A-1438G polymorphism, however, carriers with A allele tend to suffer from MDD (AA + AG vs. GG: OR = 1.20, 95 % CI = 1.02-1.43, P = 0.030). When stratified by race for T102C polymorphism and A-1438G polymorphism of the HTR2A, we found no significant association. In conclusions, our study suggests that the A allele of A-1438G polymorphism might play a role in susceptibility to MDD. On the contrary, T102C polymorphism does not seem to be capable of modifying MDD risk.

Serotonergic genes and suicidal ideation 2 weeks and 1 year after stroke in Korea

OBJECTIVES

Serotonergic genes are associated with suicidal behavior; this association has not been tested in stroke survivors, however. In this study, we investigated whether serotonin transporter (5-HTT) and serotonin 2a receptor (5-HTR2a) genes were associated with suicidal ideation at 2 weeks and at 1 year after stroke.

METHODS

A total of 286 patients were evaluated 2 weeks after stroke, and 222 (78%) participated in a follow-up evaluation one year later. Suicidal ideation was ascertained using the "suicidal thoughts" item of the Montgomery and Asberg Depression Rating Scale. Associations between suicidal ideation and 5-HTTLPR, STin2 VNTR, 5-HTR2a 1438A/G, and 5-HTR2a 102T/C genotypes were estimated using logistic regression models, and gene-gene interactions were investigated using the generalized multifactor dimensionality reduction method after adjustment for potential covariates, including depression.

RESULTS

The 5-HTR2a 1438 A/A genotype was significantly associated with suicidal ideation 2 weeks after stroke, before and after statistical adjustment. The 5-HTTLPR short allele was associated with suicidal ideation 2 weeks after stroke, although the significance of this finding was not evident after adjustment. No significant associations were observed between any genotype and suicidal ideation one year after stroke. No significant gene-gene interactions were detected.

CONCLUSIONS

Individuals with the 5-HTR2a 1438 A/A genotype were more susceptible to suicidal ideation 2 weeks after stroke. Careful evaluation and management are indicated for those with increased genetic vulnerability, particularly during the acute phase of stroke.

Serum Brain-derived neurotrophic factor levels in post-stroke depression

BACKGROUND

Depression is a frequent mood disorder that affects around a third of stroke patients and has been associated with poorer outcome. Our aim was to determine whether there is a relationship between serum Brain-derived neurotrophic factor (BDNF) levels and post-stroke depression (PSD).

METHODS

Two hundred and sixteen ischemic stroke patients admitted to the hospital within the first 24h after stroke onset were consecutively recruited and followed up for 3 months. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for post-stroke depression at day 90. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of BDNF at admission. Multivariate analyses were performed using logistic regression models.

RESULTS

In our study, 59 patients (27.3%) were diagnosed as having major depression at 3 months. Patients with major depression showed lower levels of serum BDNF [8.1 (5.6-9.4) vs. 13.7 (10.4-16.5)ng/ml, P<0.0001] at admission. In multivariate analyses, serum BDNF was an independent predictor of PSD at 3 months [odds ratio (OR): 0.79(0.72-0.87), P=0.003]. Serum levels of BDNF≤10.2ng/ml were independently associated with post-stroke (OR, 11.5; 95% CI, 5.6-23.4, P<0.0001), after adjustment for possible variables.

CONCLUSION

The present study demonstrates a strong relationship between serum BDNF levels at admission and the development of PSD within 3 months. Further studies are necessary to confirm this association, which may open the way to the proposal of new therapeutic options.

Plasma levels of glutamate during stroke is associated with development of post-stroke depression

BACKGROUND

Depression is a frequent mood disorder that affects around 33% of stroke patient. Our aim was to test the possible association between plasma glutamate and the development of post-stroke depression (PSD) in Chinese patients.

METHODS

The subjects were first-ever acute ischemic stroke (AIS) patients who were hospitalized during the period from November 2011 to September 2013. Clinical information and stroke severity was collected at admission. Neurological and neuropsychological evaluations were conducted at the 3-month follow-up. Plasma glutamate levels were analyzed at baseline using liquid chromatography followed by tandem mass spectrometry. Glutamate oxaloacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT) and blood markers were also tested. Multivariate analyses were performed using logistic regression models.

RESULTS

During the study period, 209 patients were included in the analysis. Seventy patients (33.5%) were diagnosed as having major depression at 3 month. Patients with major depression showed higher levels of plasma glutamate [299 (235-353) vs. 157 (108-206) μM, P<0.0001] and lower GOT [14 (11-20) vs. 21 (15-32)U/L, P<0.0001] at admission. In multivariate analyses, plasma glutamate and GOT were independent predictors of PSD at 3 months [odds ratio (OR): 1.03 (1.02-1.04), P<0.0001; 0.84 (0.75-0.97), P=0.003]. Plasma levels of glutamate >205 μM were independently associated with PSD (OR, 21.3; 95% CI, 8.28-67.36, P<0.0001), after adjustment for possible variables.

CONCLUSION

The present study demonstrates a strong relationship between plasma glutamate and GOT levels at admission and the development of PSD within 3 months. Further studies are necessary to confirm this association, which may open the way to the proposal of new therapeutic options.

Genetic Role of BDNF Val66Met and 5-HTTLPR Polymorphisms on Depressive Disorder

OBJECTIVE

We investigated possible association between depressive disorders and BDNF Val66Met and 5-HTTLPR. Brain derived neurotrophic factor (BDNF) gene and serotonin transporter (SLC6A4) gene are promising candidate genes for depressive disorders. It has been suggested that BDNF promotes the survival and differentiation of serotonergic neurons and that serotonergic transmission exerts powerful control over BDNF gene expression.

METHODS

Final analyses were performed on 186 patients with depressive disorders and 1032 controls. Val66Met polymorphism of BDNF gene and 5-HTTLPR polymorphism of serotonin transporter gene were genotyped and allele and genotypic associations on the diagnosis of depression and age at onset of depression were analyzed.

RESULTS

The 5-HTTLPR was positively associated with depressive affected status in the total sample and in females (p=0.038 for allelewise, p=0.015 for genotype-wise associations), but, not in males. The BDNF Val66Met showed no association with depression. BDNF Val66Met and 5-HTTLPR alone were not associated with age at onset of depression. Additional analysis on the interaction between BDNF Val66Met and 5-HTTLPR found a significant association with age at onset of depression in the entire patient group. This association was also found in the female but not in the male patient group. None of the positive results survived Bonferroni correction for multiple testing.

CONCLUSION

This result suggested that BDNF Val66Met and 5-HTTLPR may contribute to depressive disorders in a complex way and that the genetic effect could differ by gender. Further studies with large number of patients will be necessary.

A prospective study of statin use and poststroke depression

Associations between serum cholesterol levels or lipid-lowering treatment and depression risk have been controversial. Associations between statin use and depression risk have been investigated in patients with coronary artery diseases but have not been examined after stroke. This study aimed to investigate whether statin use was associated with depression ascertained at 2 weeks and 1 year after stroke. A total of 423 patients were evaluated 2 weeks after stroke, and 288 (68%) were followed 1 year later. At the 2 examinations, depression (major or minor depressive disorder) was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, and depression severity was assessed by the Hospital Anxiety and Depression Scale-Depression subscale and the Hamilton Depression Rating Scale. Logistic regression and repeated-measures analyses of variance were carried out. Statins were used in 251 (59%) of 423 patients at baseline. Statin use was not associated with poststroke depression (PSD) status at baseline but was significantly associated with reduced risk of all PSD, and of major PSD specifically, at follow-up. Statin use was also associated with better trajectories of depression assessment scale scores over the 1-year follow-up. Statin use was associated with a reduced risk of depression at 1 year after stroke. Likely causality and underlying mechanisms need to be further clarified.

Depression, 5HTTLPR and BDNF Val66Met polymorphisms, and plasma BDNF levels in hemodialysis patients with chronic renal failure

OBJECTIVE

Depression is the most prevalent comorbid psychiatric disease among hemodialysis patients with end-stage renal disease. This cross-sectional study investigated whether depression in hemodialysis patients is associated with the polymorphism of the 5' flanking transcriptional region (5-HTTLPR) of the serotonin transporter gene, the valine (Val)-to-methionine (Met) substitution at codon 66 (Val66Met) polymorphism of the brain-derived neurotrophic factor (BDNF) gene, or plasma BDNF levels.

METHODS

A total of 188 participants (mean age: 58.5±14.0 years; 89 men and 99 women) receiving hemodialysis at the Chang Gung Memorial Hospital were recruited. The diagnosis of major depressive disorder (MDD) was confirmed using the Chinese version of the Mini International Neuropsychiatric Interview. The genotypes of 5-HTTLPR and BDNF Val66Met were conducted using polymerase chain reactions plus restriction fragment length polymorphism analysis. The plasma BDNF levels were measured using an enzyme-linked immunosorbent assay kit.

RESULTS

Forty-five (23.9%) patients fulfilled the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR) criteria for a MDD. There were no significant effects of the 5-HTTLPR or BDNF Val66Met gene polymorphism on MDD among the hemodialysis patients. The plasma BDNF levels correlated significantly with age (P=0.003) and sex (P=0.047) but not with depression, the genotypes of 5-HTTLPR and BDNF Val66Met, the current antidepressant treatment, or the duration under hemodialysis.

CONCLUSION

Our results did not support the hypothesis of an involvement of the 5HTTLPR and BDNF Val66Met genotypes, or plasma BDNF levels in the pathogenesis of depression, in patients receiving hemodialysis. A study with a large sample size and homogenous patient group is warranted to confirm these findings.

Psychiatric comorbidity and quality of life in patients with post-stroke emotional incontinence

OBJECTIVE

We aimed to investigate the associations of post-stroke emotional incontinence (PSEI) with various psychiatric symptoms and quality of life independent of potential covariates in survivors of acute stroke.

METHODS

A total of 423 stroke patients were assessed within 2 weeks of the index event. Psychiatric symptoms were assessed by the Symptom Checklist-90-Revised (SCL-90-R), which has nine domains comprising Somatization, Obsessive-Compulsive, Interpersonal Sensitivity, Depression, Anxiety, Hostility, Phobic Anxiety, Paranoid Ideation, and Psychoticism. Quality of life was measured using the World Health Organization Quality of Life abbreviated form (WHOQOL-BREF), which has four domains related to physical factors, psychological factors, social relationships, and environmental context. Associations of PSEI with scores on the SCL-90-R and WHOQOL-BREF were investigated using pairwise logistic regression model adjustment for potential sociodemographic and clinical covariates.

RESULTS

PSEI was present in 51 (12.1%) patients. PSEI was associated with the Obsessive-Compulsive, Interpersonal Sensitivity, and Hostility symptom dimensions of the SCL-90-R and with the psychological factors and social relationships domains of the WHOQOL-BREF independent of important covariates including previous stroke, stroke severity, and physical disability.

CONCLUSION

PSEI causes some aspects of psychiatric distress and negatively affects psychological and interpersonal quality of life. For patients with PSEI, special attention to psychiatric comorbidity and quality of life is needed, even in the acute stage of stroke.

A longitudinal study of SLC6A4 DNA promoter methylation and poststroke depression

Serotonin transporter gene (SLC6A4) has been shown to play an important role in the pathophysiology of mood disorders including poststroke depression (PSD). SLC6A4 expression is influenced by DNA methylation status and the SLC6A4 linked promoter region (5-HTTLPR) polymorphism. This study aimed to investigate whether SLC6A4 methylation status was associated with depression ascertained at two weeks and one year after stroke taking into account the 5-HTTLPR polymorphism. A total of 286 patients were evaluated two weeks after stroke, and 222 (78%) were followed one year later. Depression was diagnosed according to DSM-IV criteria, and depression severity was assessed by the Hamilton Depression Rating Scale (HAMD) at each evaluation point. The effects of SLC6A4 methylation status on PSD status and HAMD scores were investigated using multivariate logistic regression models and partial correlation tests, respectively. Analyses were repeated after stratification by 5-HTTLPR genotype groups ('l/l or l/s' and 's/s'). Higher SLC6A4 promoter methylation status was independently associated with PSD both at 2 weeks and more prominently at 1 year after stroke, and was significantly associated with the worsening of depressive symptoms over one year. These findings were significant only in the presence of the 5-HTTLPR s/s genotype. SLC6A4 methylation profile was supported as a potential diagnostic and prognostic biomarker for PSD; associations with SLC6A4 methylation status may represent a target for drug development.

A longitudinal study of BDNF promoter methylation and genotype with poststroke depression

INTRODUCTION

Brain derived neurotrophic factor (BDNF) has been shown to play an important role in the pathophysiology of mood disorders including poststroke depression (PSD). BDNF secretion is influenced by epigenetic and genetic profiles. This study aimed to investigate whether BDNF gene promoter methylation status and val66met polymorphism were associated with depression ascertained at two weeks and one year after stroke.

METHODS

A total of 286 patients were evaluated two weeks after stroke, and 222 (78%) were followed one year later. Depression (major or minor depressive disorder) was diagnosed according to DSM-IV criteria, and classified into prevalent, persistent, and incident PSD according to presence at the two examinations. Depression severity was assessed by the Hospital Anxiety and Depression Scale-depression subscale and the Hamilton Depression Rating Scale. The effects of BDNF methylation status and genotype on PSD status were investigated using multivariate logistic regression models. The associations of BDNF methylation status and genotype with score on depression assessment scales were estimated using partial correlation tests and general linear models, respectively.

RESULTS

Higher BDNF methylation status was independently associated with prevalent, persistent and particularly with incident PSD, and with worsening depressive symptoms over follow-up but not with baseline severity. The BDNF val66met polymorphism was independently associated with prevalent PSD, but not with persistent and incident PSD nor with depressive symptoms severity. No significant methylation-genotype interactions were found.

LIMITATIONS

Methylation status was investigated with limited area of the BDNF gene and sample size was relatively small.

CONCLUSIONS

A role for BDNF in PSD was supported, and associations with BDNF gene methylation status may represent a target for drug development.

Interplay between pro-inflammatory cytokines and growth factors in depressive illnesses

The development of depressive disorders had long been attributed to monoamine variations, and pharmacological treatment strategies likewise focused on methods of altering monoamine availability. However, the limited success achieved by treatments that altered these processes spurred the search for alternative mechanisms and treatments. Here we provide a brief overview concerning a possible role for pro-inflammatory cytokines and growth factors in major depression, as well as the possibility of targeting these factors in treating this disorder. The data suggest that focusing on one or another cytokine or growth factor might be counterproductive, especially as these factors may act sequentially or in parallel in affecting depressive disorders. It is also suggested that cytokines and growth factors might be useful biomarkers for individualized treatments of depressive illnesses.

Comparative validity of depression assessment scales for screening poststroke depression

INTRODUCTION

This study aimed to compare screening properties of four assessment scales for poststroke depression (PSD) at 2 weeks and 1 year after index stroke, and investigated factors contributing to misclassification.

METHODS

A total of 423 patients were evaluated 2 weeks after stroke and 288 (68%) were followed 1 year later, and were diagnosed as having major and minor PSD applying DSM-IV criteria gold standards. The Beck Depression Inventory (BDI), Hospital Anxiety and Depression Scale-depression subscale (HADS-D), Hamilton Rating Scale for Depression (HAMD), and Montgomery-Asberg Depression Rating Scale (MADRS) were administered. The balance of sensitivity and specificity was assessed using receiver operating characteristics (ROC) analysis.

RESULTS

Discriminating abilities of all the scales for major and all PSD were good (area under ROC values 0.88-0.93 and 0.88-0.92 at 2 weeks; and 0.93-0.96 and 0.89-0.91 at 1 year, respectively). Misclassification was influenced by demographic characteristics and stroke severity particularly for the BDI and HAMD, was more marked for all PSD than for major PSD, and was more prominent at 2 weeks than at 1 year after stroke.

LIMITATIONS

Patients with only mild to moderate stroke severity were included.

CONCLUSIONS

Although there were no marked differences in the screening abilities for PSD between the scales, differences were found in factors influencing misclassification. Assessment scales with less somatic items may be recommended for the screening of PSD, particularly at the acute phase of stroke.

Associations of BDNF genotype and promoter methylation with acute and long-term stroke outcomes in an East Asian cohort

Background

Brain derived neurotrophic factor (BDNF) has been shown to play an important role in poststroke recovery. BDNF secretion is influenced by genetic and epigenetic profiles. This study aimed to investigate whether BDNF val66met polymorphism and promoter methylation status were associated with outcomes at two weeks and one year after stroke.

Methods and Findings

A total of 286 patients were evaluated at the time of admission and two weeks after stroke, and 222 (78%) were followed one year later in order to evaluate consequences of stroke at both acute and chronic stages. Stroke outcomes were dichotomised into good and poor by the modified Rankin Scale. Stroke severity (National Institutes of Health Stroke Scale), physical disability (Barthel Index), and cognitive function (Mini-Mental State Examination) were measured. Associations of BDNF genotype and methylation status on stroke outcomes and assessment scale scores were investigated using logistic regression, repeated measures ANOVA and partial correlation tests. BDNF val66met polymorphism was independently associated with poor outcome at 2 weeks and at 1 year, and with worsening physical disability and cognitive function over that period. Higher BDNF promoter methylation status was independently associated with worse outcomes at 1 year, and with the worsening of physical disability and cognitive function. No significant genotype-methylation interactions were found.

Conclusions

A role for BDNF in poststroke recovery was supported, and clinical utility of BDNF genetic and epigenetic profile as prognostic biomarkers and a target for drug development was suggested.