Genetic determinants of depression: recent findings and future directions

New Evidence for the Role of the Blood-Brain Barrier and Inflammation in Stress-Associated Depression: A Gene-Environment Analysis Covering 19,296 Genes in 109,360 Humans

Mounting evidence supports the key role of the disrupted integrity of the blood-brain barrier (BBB) in stress- and inflammation-associated depression. We assumed that variations in genes regulating the expression and coding proteins constructing and maintaining this barrier, along with those involved in inflammation, have a predisposing or protecting role in the development of depressive symptoms after experiencing severe stress. To prove this, genome-by-environment (GxE) interaction analyses were conducted on 6.26 M SNPS covering 19,296 genes on PHQ9 depression in interaction with adult traumatic events scores in the UK Biobank (n = 109,360) in a hypothesis-free setup. Among the 63 genes that were significant in stress-connected depression, 17 were associated with BBB, 23 with inflammatory processes, and 4 with neuroticism. Compared to all genes, the enrichment of significant BBB-associated hits was 3.82, and those of inflammation-associated hits were 1.59. Besides some sex differences, CSMD1 and PTPRD, encoding proteins taking part in BBB integrity, were the most significant hits in both males and females. In conclusion, the identified risk genes and their encoded proteins could provide biomarkers or new drug targets to promote BBB integrity and thus prevent or decrease stress- and inflammation-associated depressive symptoms, and possibly infection, e.g., COVID-19-associated mental and neurological symptoms.

Polygenic risk, childhood abuse and gene x environment interactions with depression development from middle to late adulthood: A U.S. national life-course study

OBJECTIVE

Utilizing national longitudinal data, this study examines how polygenic depression risk and childhood abuse interactively influence the life-course development of depressive conditions from middle to late adulthood.

METHOD

Data from 7512 participants (4323 females and 3189 males) of European ancestry aged 51-90, retrieved from the U.S. Health and Retirement Study (1992-2020), were analyzed. Childhood physical abuse and polygenic depression score were the primary predictors. Depressive symptoms were assessed using the Center for Epidemiologic Studies-Depression (CESD) scale, and clinical depression risk was a binary indicator. Growth-curve linear mixed and logit mixed-effects models were conducted for analysis.

RESULTS

Increasing polygenic depression scores were associated with elevated CES-D levels and potential risks of clinical depression. Males experienced more detrimental effects of childhood abuse on depression development from ages 51 to 90 years. In contract, non-maltreated females generally exhibited higher depressive symptoms and clinical depression risk than males. A significant interactive effect was found between polygenic depression risk and childhood abuse among males. Higher depression levels and clinical risk were observed with increasing polygenic depression score among maltreated males, surpassing those of females with standardized polygenic score ≥0 from age 51 to 90 years.

CONCLUSIONS

The interaction between childhood abuse and genetic factors significantly shaped lifelong depression trajectories in males, while the negative impact of abusive parenting remained constant regardless of polygenic depression risk among females. Individualized prevention and intervention strategies could be crucial in mitigating lifelong depression development, especially for high-genetic-risk males with a history of childhood physical abuse.

Sex Influences Genetic Susceptibility to Depression-Like Behaviors in Chronic Unpredictable Mild Stress-Exposed Wistar Rats

Depression is one of the most common mood disorders among psychiatric diseases. It affects about 10% of the adult population. However, its etiopathogenesis remains poorly understood. Exploring the dynamics of stress-susceptibility and resilience will help in understanding the molecular and biological mechanisms underlying the etiopathogenesis of depression. This study aimed to determine the differences and/or similarities in factors responsible for susceptibility to depression-like behaviors in male and female Wistar rats subjected to chronic unpredictable mild stress (CUMS). Sixty Wistar rats (30 male and 30 female) weighing between 120 and 150 g were used for this study. The rats were divided into two sub-groups: control (10) and test (20) groups. Rats in the test groups were subjected to CUMS. Depression-like behaviors were assessed using light-dark box, sucrose preference, and tail suspension tests. Rats that showed depression-like behaviors following the behavioral tests (CUMS-susceptible group) were sacrificed, and their hippocampi were excised. Genomic deoxyribonucleic acid (gDNA) was purified from the hippocampal samples. Purified gDNA was subjected to whole genome sequencing (WGS). Base-calling of sequence reads from raw sequencing signal (FAST5) files was carried out, and variants were called from alignment BAM files. The corresponding VCF files generated from the variant calling experiment were filtered. Genes were identified, their impacts estimated, and variants annotated. Functional enrichment analysis was then carried out. Approximately 41% of the male and 49% of the female rats subjected to CUMS showed significant (p < 0.05) depression-like behaviors following assessment on behavioral tests. WGS of the hippocampal DNA revealed 289,839 single nucleotide polymorphisms variant types, 7002 insertions, and 34,459 deletions in males, and 1,570,186 single nucleotide polymorphisms variant types, 109,860 insertions, and 597,241 deletions in female Wistar rats. Three genes with high-impact variants were identified in male and 22 in female Wistar rats, respectively. In conclusion, female Wistar rats are more susceptible to depression-like behaviors after exposure to CUMS than males. They also have more gene variants (especially high-impact variants) than male Wistar rats.

Cerebrospinal fluid metabolomes of treatment-resistant depression subtypes and ketamine response: a pilot study

Depression is a disorder with variable presentation. Selecting treatments and dose-finding is, therefore, challenging and time-consuming. In addition, novel antidepressants such as ketamine have sparse optimization evidence. Insights obtained from metabolomics may improve the management of patients. The objective of this study was to determine whether compounds in the cerebrospinal fluid (CSF) metabolome correlate with scores on questionnaires and response to medication. We performed a retrospective pilot study to evaluate phenotypic and metabolomic variability in patients with treatment-resistant depression using multivariate data compression algorithms. Twenty-nine patients with treatment-resistant depression provided fasting CSF samples. Over 300 metabolites were analyzed in these samples with liquid chromatography-mass spectrometry. Chart review provided basic demographic information, clinical status with self-reported questionnaires, and response to medication. Of the 300 metabolites analyzed, 151 were present in all CSF samples and used in the analyses. Hypothesis-free multivariate analysis compressed the resultant data set into two dimensions using Principal Component (PC) analysis, accounting for ~ 32% of the variance. PC1 accounted for 16.9% of the variance and strongly correlated with age in one direction and 5-methyltetrahydrofolate, homocarnosine, and depression and anxiety scores in the opposite direction. PC2 accounted for 15.4% of the variance, with one end strongly correlated with autism scores, male gender, and cognitive fatigue scores, and the other end with bipolar diagnosis, lithium use, and ethylmalonate disturbance. This small pilot study suggests that complex treatment-resistant depression can be mapped onto a 2-dimensional pathophysiological domain. The results may have implications for treatment selection for depression subtypes.

Comparison of the associations between Life's Essential 8 and Life's Simple 7 with depression, as well as the mediating role of oxidative stress factors and inflammation: NHANES 2005-2018

BACKGROUND

Cardiovascular health (CVH) is closely associated with depression. However, Life's Essential 8 (LE8), a novel CVH measure, has not yet been clearly linked to depression. This study aims to explore the association between LE8 and depression, compare its advantages over Life's Simple 7 (LS7), and investigate the mediating effects of oxidative stress and inflammation.

METHODS

This study investigated cross-sectional data of adults aged 20 and above from National Health and Nutrition Examination Survey (NHANES) 2005 to 2018. The LE8 score (ranging from 0 to 100) was derived from the American Heart Association's definition, based on the unweighted average of 8 metrics, classified as low cardiovascular health (CVH) (0-49), moderate CVH (50-79), and high CVH (80-100). Similar to LE8, LS7 scores were categorized into inadequate (0-7), average (8-10), or optimal (11-14) after calculating the unweighted mean of each component. Depression was diagnosed using the Patient Health Questionnaire (PHQ-9), with a score of ≥10 defining depression. Adjusted for sociodemographic factors and other risk factors for depression, weighted logistic regression and restricted cubic spline analysis were used to explore the correlation. Receiver operating characteristic (ROC) curves were used to study the associations between CVH scores and depression. Subsequently, subgroup analysis and sensitivity analysis were conducted, followed by an exploration of the mechanisms involved.

RESULTS

A total of 7 cycles from 2005 to 2018 contained complete data. Weighted logistic regression showed that both LS7 and LE8 were significantly associated with depression. Specifically, for LE8, after adjustment, the risk of depression decreased by 52 % for moderate CVH compared to low CVH (OR: 0.48, 95 % CI: 0.41-0.57, P < 0.0001), while the risk decreased by 80 % for high CVH (OR: 0.20, 95 % CI: 0.15-0.26, P < 0.0001, Ptrend < 0.0001). For LS7, after adjustment, compared with inadequate CVH, the risk of depression decreased by 49 % for average CVH (OR: 0.51, 95 % CI: 0.34-0.78, P = 0.002), and by 55 % for optimal CVH (OR: 0.45, 95 % CI: 0.27-0.74, P = 0.002, Ptrend < 0.0001). Area under ROC curves for predicting depression were 0.672 (95 % CI, 0.66-0.684; P < 0.001) and 0.605 (95 % CI, 0.59-0.619; P < 0.001) for LE8 and LS7 (PDeLong < 0.001), respectively. Sensitivity analysis demonstrated the robustness of the association. GGT and WBC jointly mediated 9.62 % of this association (all P < 0.001).

LIMITATIONS

The cross-sectional study cannot infer causality.

CONCLUSIONS

The association between Life's Essential 8 and depression was stronger and more practical. Oxidative stress and inflammation mediate this association. Individuals with extremely poor cardiovascular health have a 7-fold increased risk of depression, highlighting the necessity of maintaining at least moderate cardiovascular health.

Exploring the similarities between risk factors triggering depression in humans and elevated in-cage "inactive but awake" behavior in laboratory mice

Introduction

Depression is a human mental disorder that can also be inferred in non-human animals. This study explored whether time spent inactive but awake ("IBA") in the home-cage in mice was further triggered by risk factors similar to those increasing vulnerability to depression in humans (early life stress, genetic predispositions, adulthood stress).

Methods

Eighteen DBA/2 J and 18 C57BL/6 J females were tested, of which half underwent as pups a daily maternal separation on post-natal days 2-14 (early-life stress "ELS") (other half left undisturbed). To assess the effect of the procedure, the time the dams from which the 18 subjects were born spent active in the nest (proxy for maternal behavior) was recorded on post-natal days 2, 6, 10 and 14 for 1 h before separation and following reunion (matched times for controls), using live instantaneous scan sampling (total: 96 scans/dam). For each ELS condition, about half of the pups were housed post-weaning (i.e., from 27 days old on average) in either barren (triggering IBA and depression-like symptoms) or larger, highly enriched cages (n = 4-5 per group). Time mice spent IBA post-weaning was observed blind to ELS treatment using live instantaneous scan sampling in two daily 90-min blocks, two days/week, for 6 weeks (total: 192 scans/mouse). Data were analyzed in R using generalized linear mixed models.

Results

The dams were significantly more active in the nest over time (p = 0.016), however with no significant difference between strains (p = 0.18), ELS conditions (p = 0.20) and before/after separation (p = 0.83). As predicted, post-weaning barren cages triggered significantly more time spent IBA in mice than enriched cages (p < 0.0001). However, neither ELS (p = 0.4) nor strain (p = 0.84) significantly influenced time mice spent IBA, with no significant interaction with environmental condition (ELS × environment: p = 0.2861; strain × environment: p = 0.5713).

Discussion

Our results therefore only partly support the hypothesis that greater time spent IBA in mice is triggered by risk factors for human depression. We discuss possible explanations for this and further research directions.

The regulatory effects of the apelin/APJ system on depression: A prospective therapeutic target

Depression is a debilitating neuropsychological disorder characterized by high incidence, high recurrence, high suicide, and high disability rates, which poses serious threats to human health and imposes heavy psychological and economic burdens on family and society. The pathogenesis of depression is extremely complex, and its etiology is multifactorial. Mounting evidence suggests that apelin and apelin receptor APJ, which compose the apelin/APJ system, are related to the development of depression. However, the specific mechanism is still unclear, and research in this area in human is still insufficient. Acceleration of research into the regulatory effects and underlying mechanisms of the apelin/APJ system in depression may identify attractive therapeutic targets and contribute to the development of novel intervention strategies against this devastating psychological disorder. In this review, we mainly discuss the regulatory effects of apelin/APJ system on depression and its potential therapeutic applications.

Association of polygenic scores for depression and neuroticism with perceived stress in daily life during a long-lasting stress period

Genetic factors contribute significantly to interindividual differences in the susceptibility to stress-related disorders. As stress can also be conceptualized as environmental exposure, controlled gene-environment interaction (GxE) studies with an in-depth phenotyping may help to unravel mechanisms underlying the interplay between genetic factors and stress. In a prospective-longitudinal quasi-experimental study, we investigated whether polygenic scores (PGS) for depression (DEP-PGS) and neuroticism (NEU-PGS), respectively, were associated with responses to chronic stress in daily life. We examined law students (n = 432) over 13 months. Participants in the stress group experienced a long-lasting stress phase, namely the preparation for the first state examination for law students. The control group consisted of law students without particular stress exposure. In the present manuscript, we analyzed perceived stress levels assessed at high frequency and in an ecologically valid manner by ambulatory assessments as well as depression symptoms and two parameters of the cortisol awakening response. The latter was only assessed in a subsample (n = 196). No associations between the DEP-PGS and stress-related variables were found. However, for the NEU-PGS we found a significant GxE effect. Only in individuals experiencing academic stress a higher PGS for neuroticism predicted stronger increases of perceived stress levels until the exam. At baseline, a higher NEU-PGS was associated with higher perceived stress levels in both groups. Despite the small sample size, we provide preliminary evidence that the genetic disposition for neuroticism is associated with stress level increases in daily life during a long-lasting stress period.

Using smartphones to optimise and scale-up the assessment of model-based planning

Model-based planning is thought to protect against over-reliance on habits. It is reduced in individuals high in compulsivity, but effect sizes are small and may depend on subtle features of the tasks used to assess it. We developed a diamond-shooting smartphone game that measures model-based planning in an at-home setting, and varied the game's structure within and across participants to assess how it affects measurement reliability and validity with respect to previously established correlates of model-based planning, with a focus on compulsivity. Increasing the number of trials used to estimate model-based planning did remarkably little to affect the association with compulsivity, because the greatest signal was in earlier trials. Associations with compulsivity were higher when transition ratios were less deterministic and depending on the reward drift utilised. These findings suggest that model-based planning can be measured at home via an app, can be estimated in relatively few trials using certain design features, and can be optimised for sensitivity to compulsive symptoms in the general population.

Allostatic load in early adolescence: gene / environment contributions and relevance for mental health

Background

Allostatic load is the cumulative "wear and tear" on the body due to chronic adversity. We aimed to test poly-environmental (exposomic) and polygenic contributions to allostatic load and their combined contribution to early adolescent mental health.

Methods

We analyzed data on N = 5,035 diverse youth (mean age 12) from the Adolescent Brain Cognitive Development Study (ABCD). Using dimensionality reduction method, we calculated and overall allostatic load score (AL) using body mass index [BMI], waist circumference, blood pressure, blood glycemia, blood cholesterol, and salivary DHEA. Childhood exposomic risk was quantified using multi-level environmental exposures before age 11. Genetic risk was quantified using polygenic risk scores (PRS) for metabolic system susceptibility (type 2 diabetes [T2D]) and stress-related psychiatric disease (major depressive disorder [MDD]). We used linear mixed effects models to test main, additive, and interactive effects of exposomic and polygenic risk (independent variables) on AL (dependent variable). Mediation models tested the mediating role of AL on the pathway from exposomic and polygenic risk to youth mental health. Models adjusted for demographics and genetic principal components.

Results

We observed disparities in AL with non-Hispanic White youth having significantly lower AL compared to Hispanic and Non-Hispanic Black youth. In the diverse sample, childhood exposomic burden was associated with AL in adolescence (beta=0.25, 95%CI 0.22-0.29, P<.001). In European ancestry participants (n=2,928), polygenic risk of both T2D and depression was associated with AL (T2D-PRS beta=0.11, 95%CI 0.07-0.14, P<.001; MDD-PRS beta=0.05, 95%CI 0.02-0.09, P=.003). Both polygenic scores showed significant interaction with exposomic risk such that, with greater polygenic risk, the association between exposome and AL was stronger. AL partly mediated the pathway to youth mental health from exposomic risk and from MDD-PRS, and fully mediated the pathway from T2D-PRS.

Conclusions

AL can be quantified in youth using anthropometric and biological measures and is mapped to exposomic and polygenic risk. Main and interactive environmental and genetic effects support a diathesis-stress model. Findings suggest that both environmental and genetic risk be considered when modeling stress-related health conditions.

Gathering the Evidence on Diet and Depression: A Protocol for an Umbrella Review and Updated Meta-Analyses

Our objectives are to perform (1) an umbrella review on diet and depression, (2) a systematic review update on dietary patterns and depression, and (3) updated meta-analyses using studies from the previous two objectives. Systematic reviews examining the relationships between diet and depression and primary studies on the relationship between dietary patterns and depression will be systematically retrieved via several databases. All articles identified through the database searches will be imported into Covidence. Following duplicates removal, two authors will independently perform title and abstract screening and full-text assessment against eligibility criteria. Data will be extracted using tables developed for both systematic reviews and primary studies. The methodological quality of systematic reviews will be assessed using the AMSTAR-2 tool. The risk of bias in randomized trials, cohort and cross-sectional studies, as well as case-control studies, will be assessed with the Cochrane risk-of-bias (RoB-2) tool, the NHLBI Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies, and the NHLBI Quality Assessment Tool for Case-Control studies, respectively. For each dietary variable, data extracted will be used to produce: (1) a summary of systematic reviews' characteristics and results table, (2) a summary of the primary studies characteristics table, (3) a qualitative summary of results from the primary studies table, and (4) a quantitative summary of results in the form of forest plots. The certainty of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Upon completion, this systematic review will be the most comprehensive and up-to-date synthesis of currently available evidence on the relationships between diet and depression. It will serve as a key reference to guide future research and as a resource for health professionals in the fields of nutrition and psychiatry. PROSPERO CRD42022343253.

Investigation of the interaction between Genetic Risk Score (GRS) and fatty acid quality indices on mental health among overweight and obese women

BACKGROUND & AIMS

Mental disorders are associated with dietary fatty acids and genome-wide association studies have found multiple risk loci robustly related to depression, anxiety, and stress. The aim of this study is to investigate the interaction of genetic risk score (GRS) and dietary fat quality indices on mental health.

METHODS

This cross-sectional study included 279 overweight and obese women for N6/N3 ratio and 378 overweight and obese women for CSI aged 18-68 years. Using reliable and verified standard protocols, body composition, anthropometric indices, blood pressure, physical activity, and dietary fat quality were measured. Serum samples were used to determine biochemical tests. A genetic risk score (GRS) was calculated using the risk alleles of the three SNPs. A generalized linear model (GLM) was applied to assess the interactions between GRS and fat quality indices. Mental health was evaluated using Depression Anxiety Stress Scales (DASS-21).

RESULTS

The mean (± SD) age and BMI of our participants were 36.48 (8.45) and 30.73 (3.72) kg/m2 respectively. There was a marginally significant mean difference among tertiles of the CSI in terms of stress (P = 0.051), DASS-21 (P = 0.078) in the crude model. After adjusting for age, energy intake, physical activity and BMI in model 1, there was a positive interaction between GRS and T3 of N6/N3 ratio on anxiety (β = 0.91, CI = 0.08,1.75, P = 0.031), depression (β = 1.05, CI = 0.06,2.04, P = 0.037), DASS-21 (β = 2.22, CI= -0.31,4.75, P = 0.086).

CONCLUSION

Our findings indicate that higher ratio of N-6 to N-3 considering genetics were predictive of mental disorder in our population.

Kappa opioid activation changes protein profiles in different regions of the brain relevant to depression

Depression is a widespread disorder with a significant burden on individuals and society. There are various available treatments for patients with depression. However, not all patients respond adequately to their treatment. Recently, the opioid system has regained interest in depression studies. Research in animals and humans suggest that blocking the kappa opioid receptor (KOR) may potentially alleviate the symptoms of depression. The mechanism behind this effect is not fully understood. Stress and alterations in hypothalamic-pituitary-adrenal axis (HPA-axis) activity are thought to play a crucial role in depression. This study aimed to characterize stress hormones and stress-related protein expression following activation of KOR using a selective agonist. The longitudinal effect was investigated 24 h after KOR activation using the selective agonist U50,488 in Sprague Dawley rats. Stress-related hormones and protein expression patterns were explored using multiplex bead-based assays and western blotting. We found that KOR activation caused an increase in both adrenocorticotropic hormone (ACTH) and corticosterone (CORT) in serum. Regarding protein assays in different brain regions, phosphorylated glucocorticoid receptors also increased significantly in thalamus (THL), hypothalamus (HTH), and striatum (STR). C-Fos increased time-dependently in THL following KOR activation, extracellular signal-regulated kinases 1/2 (ERK1/2) increased significantly in STR and amygdala (AMG), while phosphorylated ERK1/2 decreased during the first 2 h and then increased again in AMG and prefrontal cortex (PFC). This study shows that KOR activation alters the HPA axis and ERK signaling which may cause to develop mood disorders.

Causal effects of maternal exposure to PM2.5 during pregnancy on depression symptoms in adolescence: Identifying vulnerable windows and subpopulations in a national cohort study

Few studies have examined the causal relationship between chronic exposure to air pollutants during pregnancy and depression in adolescent offspring. In addition, it has not been investigated whether exposure is most harmful to adolescents in certain populations and at certain stages of pregnancy. A total of 1975 adolescents from 1632 families from the China Family Panel Study, a representative national longitudinal cohort, were included in this study. We used high-resolution satellite retrieval data to assess the PM_2.5 exposure of mothers during pregnancy. Specifically, we employed a two-stage instrumental variable model (IV-2SLS) within the counterfactual causal inference framework, and selected and validated appropriate instruments, thereby mitigating potentially biased results arising from bi-direction between dependent and independent variables. This approach allowed us to explore the causal relationship between maternal PM_2.5 exposure during pregnancy and adolescent depression symptoms. The endogeneity of air pollution during pregnancy and the need for a causal model were suggested by the results of the model comparisons. Using the IV-2SLS model, we found that maternal exposure to PM_2.5 during pregnancy exacerbates depressive symptoms in the offspring during adolescence (β = 0.2, 95% CI: 0.05-0.34). We also found that exposure during the first trimester may cause greater harm. Adolescents with low household income, being male, irregular exercise habits, living in rural areas, and having mothers with poorer mental status may be more vulnerable. The findings suggest that maternal exposure to PM_2.5 during pregnancy may have a negative impact on the depression symptoms of offspring in adolescence and that more attention should be paid to vulnerable populations and the window of vulnerability.

Assessment of genetic variants in D2 dopamine receptor (DRD2) gene as risk factors for post-traumatic stress disorder (PTSD) and major depressive disorder (MDD): A systematic review and meta-analysis

BACKGROUND

Many studies have performed assessments of genetic variants in the D2 dopamine receptor (DRD2) gene as risk factors for post-traumatic stress disorder (PTSD) and major depressive disorder (MDD). However, the results are inconsistent. This meta-analysis aimed to systematically summarize published data to evaluate the reliable association between the DRD2 genetic variants and the risk of PTSD and MDD.

METHODS

A systematic literature search was conducted using the Web of Science, PubMed, Google Scholar, Excerpta Medica Database (EMBASE), Springer, ScienceDirect, Wiley Online Library, Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database (CBM), WANFANG Data, CQVIP, and Chinese National Knowledge Infrastructure (CNKI) databases before January 1st, 2022.

RESULTS

A total of 27 genetic variants in the DRD2 gene were retrieved, and 7 of them met the inclusion criteria for meta-analysis. Our meta-analysis results indicated that the rs1800497 (TaqIA) polymorphism was significantly associated with the increased risk of PTSD (Dominant model (A1A1 + A1A2 vs. A2A2): OR = 1.49, 95 % CI, 1.08-2.04 Z = 2.46, P = 0.014). Subgroup analysis for ethnicity suggested that a significantly increased risk of PTSD was observed in Asians (Dominant model (A1A1 + A1A2 vs. A2A2): OR = 1.39, 95 % CI, 1.08-1.79, Z = 2.60, P = 0.009) and Caucasians (Dominant model (A1A1 + A1A2 vs. A2A2): OR = 1.87, 95 % CI 1.02-3.41, Z = 2.04, P = 0.042). Meanwhile, we detected significant association strengths between the rs1799978 and rs2075652 polymorphisms in the DRD2 gene and MDD (for rs1799978, Homozygote comparison (GG vs. AA): OR = 0.60, 95 % CI = 0.37-0.97, Z = 2.08, P = 0.038; for rs2075652, Homozygote comparison (AA vs. GG): OR = 1.82, 95 % CI = 1.32-2.50, Z = 3.67, P < 0.001). Our cumulative meta-analyses indicated a continuous trend toward association strength with PTSD and MDD.

CONCLUSIONS

This meta-analysis indicated that genetic variants in the DRD2 gene might potentially contribute to genetic susceptibility for PTSD and MDD. The utilization of DRD2 genetic variants as risk factors for PTSD and MDD requires further validation by large well-designed case-control studies.

The Relationship Between Telomeres, Cognition, Mood, and Physical Function: A Systematic Review

Background and Purpose: Cognitive, affective, and physical symptoms and alterations in their function are seen across chronic illnesses. Data suggest that environmental, psychological, and physiological factors contribute to symptom experience, potentially through loss of telomeres (telomere attrition), structures at the ends of chromosomes. Telomere length is affected by many factors including environmental (e.g., exercise, diet, smoking) and physiological (e.g., response to stress), as well as from oxidative damage and inflammation that occurs in many disease processes. Moreover, telomere attrition is associated with chronic disease (cancer, cardiovascular disease, Alzheimer's disease) and predicts higher morbidity and mortality rates. However, findings are inconsistent among telomere roles and relationships with health outcomes. This article aims to synthesize the current state-of-the-science of telomeres and their relationship with cognitive, affective, and physical function and symptoms. Method: A comprehensive literature search was performed in two databases: CINAHL and PUBMED. A total of 33 articles published between 2000 and 2022 were included in the final analysis. Results: Telomere attrition is associated with various changes in cognitive, affective, and physical function and symptoms. However, findings are inconsistent. Interventional studies (e.g., meditation and exercise) may affect telomere attrition, potentially impacting health outcomes. Conclusion: Nursing research and practice are at the forefront of furthering the understanding of telomeres and their relationships with cognitive, affective, and physical function and symptoms. Future interventions targeting modifiable risk factors may be developed to improve health outcomes across populations.

Maternal genetic risk for depression and child human capital

We here address the causal relationship between the maternal genetic risk for depression and child human capital using UK birth-cohort data. We find that an increase of one standard deviation (SD) in the maternal polygenic risk score for depression reduces their children's cognitive and non-cognitive skill scores by 5 to 7% of a SD throughout adolescence. Our results are robust to a battery of sensitivity tests addressing, among others, concerns about pleiotropy and dynastic effects. Our Gelbach decomposition analysis suggests that the strongest mediator is genetic nurture (through maternal depression itself), with genetic inheritance playing only a marginal role.

Sociodemographic characteristics and health-related quality of life of individuals undergoing antidepressant therapy

An important factor for averting depression and creating awareness about clinical treatment is patient preference. Therefore, investigating health-related quality of life associated with different antidepressants is necessary. A retrospective cohort study was performed using the 2018 Medical Expenditure Panel Survey. The MEPS is a nationally representative database of the civilian and noninstitutionalized population spanning different ages, both sexes, and a wide range of sociodemographic and economic backgrounds. Differences in clinical and sociodemographic characteristics among patients using different antidepressant classes were explored. The differences in Veterans RAND 12-Item Health Survey (VR-12) results among groups were examined. The VR-12 metric was used since it measures a patient's overall perspective of their health. Approximately 34.6 million of the patients reported using at least one antidepressant during 2018. Most patients receiving tricyclic therapy reported substantially better mental HRQoL than patients receiving selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), or combination therapy. Patients receiving atypical antidepressants reported substantially better mental HRQoL than those receiving other types of antidepressants. Most patients reported a substantial decline in HRQoL after SNRIs or combination therapy. This study found that HRQoL varied across antidepressant users. Thus, health care providers could benefit from taking into consideration quality of life when prescribing antidepressant agents. Moreover, further research is needed to explore other factors that could contribute to the quality of care for patients with depression.

Sociodemographic characteristics and health-related quality of life of individuals undergoing antidepressant therapy

An important factor for averting depression and creating awareness about clinical treatment is patient preference. Therefore, investigating health-related quality of life associated with different antidepressants is necessary. A retrospective cohort study was performed using the 2018 Medical Expenditure Panel Survey. The MEPS is a nationally representative database of the civilian and noninstitutionalized population spanning different ages, both sexes, and a wide range of sociodemographic and economic backgrounds. Differences in clinical and sociodemographic characteristics among patients using different antidepressant classes were explored. The differences in Veterans RAND 12-Item Health Survey (VR-12) results among groups were examined. The VR-12 metric was used since it measures a patient's overall perspective of their health. Approximately 34.6 million of the patients reported using at least one antidepressant during 2018. Most patients receiving tricyclic therapy reported substantially better mental HRQoL than patients receiving selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), or combination therapy. Patients receiving atypical antidepressants reported substantially better mental HRQoL than those receiving other types of antidepressants. Most patients reported a substantial decline in HRQoL after SNRIs or combination therapy. This study found that HRQoL varied across antidepressant users. Thus, health care providers could benefit from taking into consideration quality of life when prescribing antidepressant agents. Moreover, further research is needed to explore other factors that could contribute to the quality of care for patients with depression.

Genetic and environmental contributions to psychopathological symptoms stability and change across the COVID-19 pandemic

Several longitudinal studies investigated changes in mental health related to the pandemic event. However, little research has focused on the mediating role of environmental and genetic factors. The current prospective study aimed to evaluate the genetic and environmental contributions to the stability of symptoms of depression, anxiety and stress during the COVID-19 crisis. A total of 798 adult twins, previously enrolled in the Italian Twin Register, participated in the study and completed on-line questionnaires sent out on June 2020 and December 2020. The nine-item Patient Health Questionnaire (PHQ-9), the six-item State-Trait Anxiety Inventory (STAI-6), and the Impact of Event Scale - Revised (IES-R) were administered to assess depressive and anxiety symptoms, and pandemic-related subjective distress, respectively. A considerable longitudinal stability was observed for each trait (range: 0.57, STAI-6 - 0.67, PHQ-9). Bivariate Cholesky decomposition indicated that genetic factors explained from 53% (IES-R) to 61% (STAI-6) of between-wave covariance and that genetic overlap between the two waves was almost complete (range: 0.91, STAI-6 - 0.99, PHQ-9). Our findings support the hypothesis, at least over the 6-month period examined, of a genetic stability between waves and of an environmental discontinuity due to changes in life conditions during the pandemic.

Socio-Economic Development and Mental Health: Case Study of the Spanish Region of Aragon (2010-20)

Introduction

Considering health as a cross-cutting element of all public policies leads to rethinking its interactions with the environment in which people live. The collection of large volumes of data by public administrations offers the opportunity to monitor and analyze the possible associations between health and territory. The increase in the incidence and prevalence of mental health diseases, particularly depression, justifies the need to develop studies that seek to identify links with the socioeconomic and environmental setting.

Objective

The objective of this study is to explain the behavior of the depression in a mediterranean region of Northeastern Spain from an ecological and diachronic perspective.

Methods

We conducted a correlation and multivariate logistic regression analysis to identify explanatory factors of the prevalence of depression in 2010 and 2020 and in the variation rate. Potential explanatory factors are related to the socioeconomic status and to the territorial development level.

Results

The regression models retained both socioeconomic and territorial development variables as predictors of the prevalence in both years and in the variation rate. Rural areas seem to play a protective role against the prevalence.

Conclusion

It is under the territorial prism that epidemiological studies could offer useful guidelines for proactive decision-making. The integration of data on diseases and territory must be considered when developing policies for the creation of healthier environments and for directing health services with more specific resources to where they may be needed.

Mechanisms and Methods to Understand Depressive Symptoms

Depressive symptoms, feelings of sadness, anger, and loss that interfere with a person's daily life, are prevalent health concerns across populations that significantly result in adverse health outcomes with direct and indirect economic burdens at a national and global level. This article aims to synthesize known mechanisms of depressive symptoms and the established and emerging methodologies used to understand depressive symptoms; implications and directions for future nursing research are discussed. A comprehensive search was performed by Cumulative Index to Nursing and Allied Health Literature, MEDLINE, and PUBMED databases between 2000-2021 to examine contributing factors of depressive symptoms. Many environmental, psychological, and physiological factors are associated with the development or increased severity of depressive symptoms (anhedonia, fatigue, sleep and appetite disturbances to depressed mood). This paper discusses biological and psychological theories that guide our understanding of depressive symptoms, as well as known biomarkers (gut microbiome, specific genes, multi-cytokine, and hormones) and established and emerging methods. Disruptions within the nervous system, hormonal and neurotransmitters levels, brain structure, gut-brain axis, leaky-gut syndrome, immune and inflammatory process, and genetic variations are significant mediating mechanisms in depressive symptomology. Nursing research and practice are at the forefront of furthering depressive symptoms' mechanisms and methods. Utilizing advanced technology and measurement tools (big data, machine learning/artificial intelligence, and multi-omic approaches) can provide insight into the psychological and biological mechanisms leading to effective intervention development. Thus, understanding depressive symptomology provides a pathway to improve patients' health outcomes, leading to reduced morbidity and mortality and the overall nation-wide economic burden.Supplemental data for this article is available online at https://doi.org/10.1080/01612840.2021.1998261 .

Depression before and during-COVID-19 by Gender in the Korean Population

This study explored the association between Coronavirus disease (COVID-19) and depression by comparing Patient Health Questionnaire-9 (PHQ-9) results pre-pandemic (2019) and after the start of the pandemic (2020). Data of 444,051 participants (200,206 male (45.1%); 243,845 female (54.9%)) were obtained from the Korean Community Health Survey conducted from 2019 to 2020. The independent variable of interest in this study was the year, divided into binary categories, 2019 and 2020. The dependent variable was depression, measured by the PHQ-9 scale. This dependent variable was also binary, dividing those who are considered depressed or not by a cut-off score of 10. A logistic regression model was employed to examine the association. Our results reveal that compared to participants in 2019, patients from the study sample of 2020 were marginally more likely to be depressed, especially female patients (male OR: 1.092, 95% CI [0.998 to 1.195], female OR: 1.066, 95% CI [1.002 to 1.134]). Moreover, using the participants from the year 2019 as a reference group, those who appeared anxious in response to the COVID-19-related questions in the survey showed more tendency to have a PHQ-9 score of 10 or more. Compared to participants from the 2019 group, those from 2020 more likely to be depressed were those with no-one to contact in case of emergency due to COVID-19 (male OR: 1.45, 95% CI [1.26 to 1.66], female OR: 1.46, 95% CI [1.33 to 1.60]), and individuals with concerns regarding economic loss (male OR: 1.18, 95% CI [1.07 to 1.30], female OR: 1.11, 95% CI [1.04 to 1.18]) and infection of a vulnerable family member at home due to COVID-19 (male OR: 1.16, 95% CI [1.05 to 1.28], female OR: 1.09, 95% CI [ 1.02 to 1.16]).

Translational Informatics for Natural Products as Antidepressant Agents

Depression, a neurological disorder, is a universally common and debilitating illness where social and economic issues could also become one of its etiologic factors. From a global perspective, it is the fourth leading cause of long-term disability in human beings. For centuries, natural products have proven their true potential to combat various diseases and disorders, including depression and its associated ailments. Translational informatics applies informatics models at molecular, imaging, individual, and population levels to promote the translation of basic research to clinical applications. The present review summarizes natural-antidepressant-based translational informatics studies and addresses challenges and opportunities for future research in the field.

Identification of putative genetic variants in major depressive disorder patients in Pakistan

BACKGROUND

Major depressive disorder (MDD) is a polygenic, and highly prevalent disorder affecting 322 million people globally. It results in several psychological changes which adversely affect different dimensions of life and may lead to suicide.

METHODS

Whole exome sequencing of 15 MDD patients, enrolled at the Dr. A. Q. Khan Institute of Behavioral Sciences, Karachi, was performed using NextSeq500. Different bioinformatics tools and databases like ANNOVAR, ALoFT, and GWAS were used to identify both common and rare variants associated with the pathogenesis of MDD.

RESULTS

A total of 1985 variations were identified in 479 MDD-related genes. Several SNPs including rs1079610, rs11750538, rs1799913, rs1801131, rs2230267, rs2231187, rs3819976, rs4314963, rs56265970, rs587780434, rs6330, rs75111588, rs7596487, and rs9624909 were prioritized due to their deleteriousness and frequency difference between the patients and the South Asian population. A non-synonymous variation rs56265970 (BCR) had 26% frequency in patients and was not found in the South Asian population; a multiallelic UTR-5' insertion rs587780434 (RELN) was present with an allelic frequency of 70% in patients whereas 22% in the SAS population. Genetic alterations in PABPC1 genes, a stress-associated gene also had higher allele frequency in the cases than in the normal population.

CONCLUSION

This present study identifies both common and rare variants in the genes associated with the pathogenesis of MDD in Pakistani patients. Genetic variations in BCR, RELN, and stress-associated PABPC1 suggest potential roles in the pathogenesis of MDD.

Sensitive period-regulating genetic pathways and exposure to adversity shape risk for depression

Animal and human studies have documented the existence of developmental windows (or sensitive periods) when experience can have lasting effects on brain structure or function, behavior, and disease. Although sensitive periods for depression likely arise through a complex interplay of genes and experience, this possibility has not yet been explored in humans. We examined the effect of genetic pathways regulating sensitive periods, alone and in interaction with common childhood adversities, on depression risk. Guided by a translational approach, we: (1) performed association analyses of three gene sets (60 genes) shown in animal studies to regulate sensitive periods using summary data from a genome-wide association study of depression (n = 807,553); (2) evaluated the developmental expression patterns of these genes using data from BrainSpan (n = 31), a transcriptional atlas of postmortem brain samples; and (3) tested gene-by-development interplay (dGxE) by analyzing the combined effect of common variants in sensitive period genes and time-varying exposure to two types of childhood adversity within a population-based birth cohort (n = 6254). The gene set regulating sensitive period opening associated with increased depression risk. Notably, 6 of the 15 genes in this set showed developmentally regulated gene-level expression. We also identified a statistical interaction between caregiver physical or emotional abuse during ages 1-5 years and genetic risk for depression conferred by the opening genes. Genes involved in regulating sensitive periods are differentially expressed across the life course and may be implicated in depression vulnerability. Our findings about gene-by-development interplay motivate further research in large, more diverse samples to further unravel the complexity of depression etiology through a sensitive period lens.

The Genetic Architecture of Depression in Individuals of East Asian Ancestry: A Genome-Wide Association Study

Importance

Most previous genome-wide association studies (GWAS) of depression have used data from individuals of European descent. This limits the understanding of the underlying biology of depression and raises questions about the transferability of findings between populations.

Objective

To investigate the genetics of depression among individuals of East Asian and European descent living in different geographic locations, and with different outcome definitions for depression.

Design, Setting, and Participants

Genome-wide association analyses followed by meta-analysis, which included data from 9 cohort and case-control data sets comprising individuals with depression and control individuals of East Asian descent. This study was conducted between January 2019 and May 2021.

Exposures

Associations of genetic variants with depression risk were assessed using generalized linear mixed models and logistic regression. The results were combined across studies using fixed-effects meta-analyses. These were subsequently also meta-analyzed with the largest published GWAS for depression among individuals of European descent. Additional meta-analyses were carried out separately by outcome definition (clinical depression vs symptom-based depression) and region (East Asian countries vs Western countries) for East Asian ancestry cohorts.

Main Outcomes and Measures

Depression status was defined based on health records and self-report questionnaires.

Results

There were a total of 194 548 study participants (approximate mean age, 51.3 years; 62.8% women). Participants included 15 771 individuals with depression and 178 777 control individuals of East Asian descent. Five novel associations were identified, including 1 in the meta-analysis for broad depression among those of East Asian descent: rs4656484 (β = -0.018, SE = 0.003, P = 4.43x10-8) at 1q24.1. Another locus at 7p21.2 was associated in a meta-analysis restricted to geographically East Asian studies (β = 0.028, SE = 0.005, P = 6.48x10-9 for rs10240457). The lead variants of these 2 novel loci were not associated with depression risk in European ancestry cohorts (β = -0.003, SE = 0.005, P = .53 for rs4656484 and β = -0.005, SE = 0.004, P = .28 for rs10240457). Only 11% of depression loci previously identified in individuals of European descent reached nominal significance levels in the individuals of East Asian descent. The transancestry genetic correlation between cohorts of East Asian and European descent for clinical depression was r = 0.413 (SE = 0.159). Clinical depression risk was negatively genetically correlated with body mass index in individuals of East Asian descent (r = -0.212, SE = 0.084), contrary to findings for individuals of European descent.

Conclusions and Relevance

These results support caution against generalizing findings about depression risk factors across populations and highlight the need to increase the ancestral and geographic diversity of samples with consistent phenotyping.

Association study of six candidate genes with major depressive disorder in the North-Western population of Pakistan

People around the world are currently affected by Major Depressive Disorder (MDD). Despite its many aspects, symptoms, manifestations and impacts, efforts have been made to identify the root causes of the disorder. In particular, genetic studies have concentrated on identifying candidate genes for MDD and exploring associations between these genes and some specific group of individuals. The aim of this research was to find out the association between single nucleotide polymorphisms in 6 candidate genes linked to the neurobiology of major depressive disorder in the North-Western population of Pakistan. We performed a case-control analysis, with 400 MDD and 232 controls. A trained psychiatrist or clinical psychologists evaluated the patients. Six polymorphisms were genotyped and tested for allele and genotype association with MDD. There were no statistical variations between MDD patients and healthy controls for genotypic and allelic distribution of all the polymorphisms observed. Thus, our analysis does not support the major role of these polymorphisms in contributing to MDD susceptibility, although it does not preclude minor impact. The statistically significant correlation between six polymorphisms and major depressive disorder in the studied population was not observed. There are inconsistencies in investigations around the world. Future research, including GWAS and association analysis on larger scale should be addressed for further validation and replication of the present findings.

Efficacy of a Functional Therapy Program for Depression and C-Reactive Protein: A Pilot Study

OBJECTIVE

Affecting more than 264 million people, depression is a systemic and multifactorial disorder that represents one of the leading causes of illness and disability worldwide. Several studies showed an inflammatory response in depressed patients, including the involvement of both chronic low-grade inflammatory response and activation of cell-mediated immunity. The present study aimed to verify the efficacy of a structured functional therapy program for patients with depressed mood, and to determine whether this program can significantly reduce levels of C-reactive protein.

METHOD

28 outpatients with depressed mood received 20 individual sessions of Functional therapy. Data about socio-demographic variables, depression, self-esteem, and quality of life were collected; moreover, blood specimens were collected before and after treatment, and CRP measurement was performed by immunoenzymatic method. All measures were administered at baseline, at the end of treatment (i.e., 3 months after baseline), and at follow-up (i.e., 6 months after baseline).

RESULTS

A repeated measures ANOVA showed a significant difference after treatment on depression levels, levels of self-esteem, and all dimensions of quality of life, such as physical, psychological, social relationships, and environment. Furthermore, a statistically significant difference on levels of CRP was found. Moreover, at follow-up, improvements were maintained.

CONCLUSIONS

The study revealed initial evidence of the efficacy of a functional therapy program on treating depression and its psychological and inflammation-related markers.

Major Depressive Disorder: Advances in Neuroscience Research and Translational Applications

Major depressive disorder (MDD), also referred to as depression, is one of the most common psychiatric disorders with a high economic burden. The etiology of depression is still not clear, but it is generally believed that MDD is a multifactorial disease caused by the interaction of social, psychological, and biological aspects. Therefore, there is no exact pathological theory that can independently explain its pathogenesis, involving genetics, neurobiology, and neuroimaging. At present, there are many treatment measures for patients with depression, including drug therapy, psychotherapy, and neuromodulation technology. In recent years, great progress has been made in the development of new antidepressants, some of which have been applied in the clinic. This article mainly reviews the research progress, pathogenesis, and treatment of MDD.

Teenagers and Precision Psychiatry: A Window of Opportunity

OBJECTIVE

Precision medicine raises hope for translating genetic-based knowledge about psychiatric risks into mental health benefits by motivating health-related, risk-reducing behaviors. Teenagers (ages 14-17) are an important age-group to engage in preventive efforts but, their views about psychiatric genetics are understudied.

METHOD

An online survey with a nationally representative sample of teenagers (n = 417) was conducted. Participants were randomly assigned to receive 1 of 2 handouts, 1 emphasizing the genetic underpinnings of psychiatric conditions; the other agency-oriented and focusing on gene-environment interactions. Survey questions queried their views about behavioral changes in response to psychiatric genetic risk information and expressed willingness to undertake them. Participants' decision-making characteristics (i.e., self-efficacy, empowerment, intolerance of uncertainty, and sensation-seeking) were assessed at baseline.

RESULTS

Teenagers strongly valued the information provided and its potential usefulness for their mental health. Information about psychiatric genetics alone impacted views about the causes of mental illness. Contrary to our hypothesis, the type of handout did not impact participants' expressed willingness to make behavioral changes to reduce their risk of developing a psychiatric condition, but their sense of empowerment played a key role in their responses.

CONCLUSION

Educating teenagers about gene-environment interactions may help facilitate the translational efforts of precision psychiatry. Research with teenagers across racial/ethnic groups, especially those with family histories, is needed to better understand the factors that impact teenagers' empowerment in psychiatric genomic settings and to identify measures, including the best enablers of empowerment (e.g., educators, parents), which would allow them to reap the benefits of precision psychiatry.

Interaction of CEND1 gene and life events in susceptibility to depressive symptoms in Chinese Han college students

BACKGROUND

. The development of depressive symptoms (DSs) is a complex process caused by both genetic and environmental factors. CEND1 gene coordinates cell division, differentiation and maturation of neural precursor cells, which affects brain structure and function. Our study investigated whether CEND1 was a genetic factor for DSs, particularly under negative life events.

METHODS

. 272 freshmen with DSs and 467 healthy controls were recruited via the Center for Epidemiologic Studies Depression Scale (CES-D). The adolescent Self-rating Life Event Checklist (ASLEC) was adopted to assess stressful life events during the past 12 months. Two SNPs (rs7946354, rs6597982) within the CEND1 gene were genotyped using Agena MassARRAY iPLEX technology. We combined generalized multifactor dimensionality reduction (GMDR) with RStudio programming to assess the direct association and gene-environment interaction (G × E).

RESULTS

. Rs7946354 was associated with DSs in an overdominant model (GT vs. GG+TT). In addition, both rs7946354 and rs6597982 had considerable impacts on negative life events. GMDR showed a statistical G × E that the AG genotype of rs6597982 and GT genotype of rs7946354 contribute to the maximum risk of DSs under high negative life events.

LIMITATIONS

. Only two single nucleotide polymorphisms (SNPs) were examined. Verification studies with bigger sample size and more varied demographic background information could be adopted to further support the generalization of these findings.

CONCLUSIONS

.CEND1 can potentially cause high sensitivity to life events and affect DSs especially in the presence of negative life events, which contribute to the field of depression prevention and treatment.

Application of a diathesis-stress model to the interplay of cortical structural development and emerging depression in youth

Cross-sectional studies in adults have long identified differences in cortical structure in adults with depression compared to healthy adults, with most studies identifying reductions in grey matter volume, cortical thickness, and surface area in primarily frontal cortical regions including the OFC, ACC, and variable sub-regions of the PFC. However, when, why, and for whom these neural correlates of depression emerge remains poorly understood, necessitating developmental study of associations between depression and cortical structure. We systematically reviewed studies examining these associations in child/adolescent samples, and applied a developmentally-focused diathesis-stress model to understand the impacts of depressogenic risk-factors and stressors on the development of structural neural correlates of depression. Cross-sectional findings in youth are generally similar to those found in adults, but vary in magnitude and direction of effects. Preliminary evidence suggests that age, sex, severity, and comorbidity moderate these associations. Longitudinal studies show depression prospectively predicting cortical structure and structure predicting emerging depression. Consistent with a diathesis-stress model, associations have been noted between risk-factors for depression (e.g., genetic risk, family risk) and environmental stressors (e.g., early life stress) and structural neural correlates. Further investigation of these associations across development with attention to vulnerability factors and stressors is indicated.

Eliciting Willingness and Beliefs towards Participation in Genetic Psychiatric Testing in Black/African American Mothers at Risk for Depression

Black/African American women are at high risk for depression, yet are underrepresented in psychiatric genetic research for depression prevention and treatment. Little is known about the factors that influence participation in genetic testing for Black/African American women at risk. The purpose of this study was to elicit the beliefs that underlie participation in genetic testing for depression in Black/African American mothers, a subgroup at high risk. Willingness to participate in genetic testing procedures was also determined. A qualitative, descriptive design was employed. Exactly 19 mothers aged 21–42 completed open-ended questionnaires. Directed content and descriptive analyses of the text were conducted based on the Theory of Planned Behavior. Salient beliefs included: behavioral advantages—diagnosing/detecting depression (31.6%), finding cure/treatment (21.1%); disadvantages—not finding follow-up treatment/help (21.1%); salient referents, who approves—family members (47.4%), agencies/organizations (26.3%); who disapproves—church associates (21.1%). Control beliefs included: barriers—unpleasant/difficult testing procedures (42.1%), limited knowledge about the purpose of testing (26.3%); facilitator—a convenient location (21.1%). Most mothers (89.5%) indicated willingness to participate in testing. Interventions can target families, address barriers, emphasize future benefits, and use convenient locations and community-based participatory research methods. Policies can address social determinants of participation to increase inclusion of these mothers in psychiatric genetic research.

Interactions of childhood maltreatment and genetic variations in adult depression: A systematic review

Background Childhood maltreatment (CM) significantly increases the risk of adulthood psychopathology. Interplay between susceptible genetic variations and CM contributes to the occurrence of depression. This review aims to systematically synthesize the relationships between genetic variations and depression among those exposed to CM. Methods Electronic databases and gray literature to March 31st, 2020 were searched for literature on the topic of depression and CM limited to English-language. Data extraction and quality assessment of key study characteristics were conducted. Qualitative approaches were used to synthesize the findings. Results The initial search resulted in 9185 articles. A total of 29 articles that met the eligibility criteria were included in this review. High heterogeneity was identified regarding the study sample ages, candidate genes and SNPs, the categorization of CM and depression. The findings of this review include several frequently studied genes (5-HTTLPR, CRHR1, BDNF, CREB1, FKBP5, IL1B, NTRK2, and OXTR). Both consistent and inconsistent findings were identified. Overall, the interplay of CM with CREB1-rs2253206 significantly increased the risk of depression. In contrast, CRHR1-TCA haplotype (rs7209436, rs4792887, rs110402), CRHR1-rs17689882, and CRHR1-rs110402 showed protective effects on depression and depressive symptoms among individuals with a history of maltreatment. Limitations Due to clinical and methodological diversity of the studies a qualitative approach was used. Conclusion This review firstly provides a comprehensive overview of the interplay between CM and genetic variations in adult depression. Future etiological explorations should focus on the above-identified genes for down-stream exploration and address the issues and challenges of gene by environment studies.

Depression-like behaviors induced by defective PTPRT activity through dysregulated synaptic functions and neurogenesis

PTPRT has been known to regulate synaptic formation and dendritic arborization of hippocampal neurons. PTPRT-/- null and PTPRT-D401A mutant mice displayed enhanced depression-like behaviors compared with wild-type mice. Transient knockdown of PTPRT in the dentate gyrus enhanced the depression-like behaviors of wild-type mice, whereas rescued expression of PTPRT ameliorated the behaviors of PTPRT-null mice. Chronic stress exposure reduced expression of PTPRT in the hippocampus of mice. In PTPRT-deficient mice the expression of GluR2 (also known as GRIA2) was attenuated as a consequence of dysregulated tyrosine phosphorylation, and the long-term potentiation at perforant-dentate gyrus synapses was augmented. The inhibitory synaptic transmission of the dentate gyrus and hippocampal GABA concentration were reduced in PTPRT-deficient mice. In addition, the hippocampal expression of GABA transporter GAT3 (also known as SLC6A11) was decreased, and its tyrosine phosphorylation was increased in PTPRT-deficient mice. PTPRT-deficient mice displayed reduced numbers and neurite length of newborn granule cells in the dentate gyrus and had attenuated neurogenic ability of embryonic hippocampal neural stem cells. In conclusion, our findings show that the physiological roles of PTPRT in hippocampal neurogenesis, as well as synaptic functions, are involved in the pathogenesis of depressive disorder.

Genome-wide gene-environment analyses of major depressive disorder and reported lifetime traumatic experiences in UK Biobank

Depression is more frequent among individuals exposed to traumatic events. Both trauma exposure and depression are heritable. However, the relationship between these traits, including the role of genetic risk factors, is complex and poorly understood. When modelling trauma exposure as an environmental influence on depression, both gene-environment correlations and gene-environment interactions have been observed. The UK Biobank concurrently assessed Major Depressive Disorder (MDD) and self-reported lifetime exposure to traumatic events in 126,522 genotyped individuals of European ancestry. We contrasted genetic influences on MDD stratified by reported trauma exposure (final sample size range: 24,094-92,957). The SNP-based heritability of MDD with reported trauma exposure (24%) was greater than MDD without reported trauma exposure (12%). Simulations showed that this is not confounded by the strong, positive genetic correlation observed between MDD and reported trauma exposure. We also observed that the genetic correlation between MDD and waist circumference was only significant in individuals reporting trauma exposure (rg = 0.24, p = 1.8 × 10-7 versus rg = -0.05, p = 0.39 in individuals not reporting trauma exposure, difference p = 2.3 × 10-4). Our results suggest that the genetic contribution to MDD is greater when reported trauma is present, and that a complex relationship exists between reported trauma exposure, body composition, and MDD.

Association Between a Functional Polymorphism in the Monoamine Oxidase A (MAOA) Gene and Both Emotional Coping Style and Neuroticism

Background:

Identification of novel genetic factors for Depressive Disorders (DD) represents a major challenge around the world. Molecular studies of endophenotypes associated with DD, such as personality traits and coping, are powerful strategies for finding genetic markers.

Objective:

The main objective of this work was to confirm the potential relationship between a functional polymorphism in the monoamine oxidase A (MAOA) gene and scores in coping and neuroticism in young adults.

Methods:

A Colombian sample of two hundred fifty-one young participants was evaluated with the short forms of the Coping Inventory for Stressful Situations (CISS-SF) and the Big Five Inventory (BFI-S). Genotypes for MAOA-VNTR polymorphism were obtained by PCR.

Results:

A significant relationship between the functional MAOA-VNTR polymorphism and scores in both emotion-oriented coping and neuroticism was found. Individuals carrying the 4 allele (3/4 or 4/4 genotypes) had higher scores for both emotion-oriented coping and neuroticism than individuals with a 3/3 genotype.

Conclusion:

Our current findings are novel in terms of being the first report of a relationship between a functional polymorphism in the MAOA gene and coping and add evidence to the association of this gene with neuroticism. Our results expand the associations between MAOA gene and multiple dimensions of human emotion and personality.

Efficacy of a fasting-mimicking diet in functional therapy for depression: A randomised controlled pilot trial

OBJECTIVE

This randomized controlled trial examined the efficacy of adding a fasting-mimicking diet to a structured psychotherapy protocol for treating depression.

DESIGN

Of 20 patients with depression, 10 were randomly assigned to psychotherapy and dieting (i.e., experimental group) and the other 10 to psychotherapy only (i.e., control group). Patients in both groups received 20 individual sessions of functional therapy along with nutrition consultation. Patients in the control group were instructed to maintain their usual daily diets.

RESULTS

Both treatments were effective in reducing depression as well as increasing self-esteem and quality of life. The experimental group showed improved self-esteem and psychological quality of life as well as a reduction in their mean body mass index, in comparison to the control group.

CONCLUSIONS

The study revealed initial evidence of the efficacy of combining psychotherapy with a fasting-mimicking diet to treat depression and its correlates.

A phenome-wide association and Mendelian Randomisation study of polygenic risk for depression in UK Biobank

Depression is a leading cause of worldwide disability but there remains considerable uncertainty regarding its neural and behavioural associations. Here, using non-overlapping Psychiatric Genomics Consortium (PGC) datasets as a reference, we estimate polygenic risk scores for depression (depression-PRS) in a discovery (N = 10,674) and replication (N = 11,214) imaging sample from UK Biobank. We report 77 traits that are significantly associated with depression-PRS, in both discovery and replication analyses. Mendelian Randomisation analysis supports a potential causal effect of liability to depression on brain white matter microstructure (β: 0.125 to 0.868, p_FDR < 0.043). Several behavioural traits are also associated with depression-PRS (β: 0.014 to 0.180, p_FDR: 0.049 to 1.28 × 10⁻¹⁴) and we find a significant and positive interaction between depression-PRS and adverse environmental exposures on mental health outcomes. This study reveals replicable associations between depression-PRS and white matter microstructure. Our results indicate that white matter microstructure differences may be a causal consequence of liability to depression.

Depression is correlated with many brain-related traits. Here, Shen et al. perform phenome-wide association studies of a depression polygenic risk score (PRS) and find associations with 51 behavioural and 26 neuroimaging traits which are further followed up on using Mendelian randomization and mediation analyses.

Role of rs454214 in Personality mediated Depression and Subjective Well-being

Happiness and depression are interlinked and both heritable, while personality, as an important predictor of them, shares the genetic basis with them. We conjecture that genetic factors of depression can affect both depressive symptoms (DS) and subjective well-being (SWB), while personality traits play important roles in mediating this process. In this study, 878 Han Chinese college freshmen and 384 Han Chinese patients with the major depressive disorder (MDD) were included. SNPs were genotyped using AGENA MassARRAY iPLEX technology and we investigated an important MDD variant rs454214. Correlation, association and mediation analysis were employed, aiming to decipher the complex relationship between SWB, DS, personality traits and the genetic variant. Association study indicated that rs454214 was not only associated with both SWB and DS (P < 0.05), but also possibly linked to MDD. Mediational analysis showed that rs454214 had no direct effect on SWB and DS, but had a significant indirect effect through personality traits, i.e., Extraversion, Neuroticism, Agreeableness and Openness to Experience or SWB, Extraversion, Neuroticism and Agreeableness for DS. This study found a shared genetic basis for happiness and depression; the causal process could be better explained if personality traits are taken as mediating factors.

Teeth as Potential New Tools to Measure Early-Life Adversity and Subsequent Mental Health Risk: An Interdisciplinary Review and Conceptual Model

Early-life adversity affects nearly half of all youths in the United States and is a known risk factor for psychiatric disorders across the life course. One strategy to prevent mental illness may be to target interventions toward children who are exposed to adversity, particularly during sensitive periods when these adversities may have even more enduring effects. However, a major obstacle impeding progress in this area is the lack of tools to reliably and validly measure the existence and timing of early-life adversity. In this review, we summarize empirical work across dentistry, anthropology, and archaeology on human tooth development and discuss how teeth preserve a time-resolved record of our life experiences. Specifically, we articulate how teeth have been examined in these fields as biological fossils in which the history of an individual's early-life experiences is permanently imprinted; this area of research is related to, but distinct from, studies of oral health. We then integrate these insights with knowledge about the role of psychosocial adversity in shaping psychopathology risk to present a working conceptual model, which proposes that teeth may be an understudied yet suggestive new tool to identify individuals at risk for mental health problems following early-life psychosocial stress exposure. We end by presenting a research agenda and discussion of future directions for rigorously testing this possibility and with a call to action for interdisciplinary research to meet the urgent need for new biomarkers of adversity and psychiatric outcomes.

Analyzing the genes and pathways related to major depressive disorder via a systems biology approach

INTRODUCTION

Major depressive disorder (MDD) is a mental disorder caused by the combination of genetic, environmental, and psychological factors. Over the years, a number of genes potentially associated with MDD have been identified. However, in many cases, the role of these genes and their relationship in the etiology and development of MDD remains unclear. Under such situation, a systems biology approach focusing on the function correlation and interaction of the candidate genes in the context of MDD will provide useful information on exploring the molecular mechanisms underlying the disease.

METHODS

We collected genes potentially related to MDD by screening the human genetic studies deposited in PubMed (https://www.ncbi.nlm.nih.gov/pubmed). The main biological themes within the genes were explored by function and pathway enrichment analysis. Then, the interaction of genes was analyzed in the context of protein-protein interaction network and a MDD-specific network was built by Steiner minimal tree algorithm.

RESULTS

We collected 255 candidate genes reported to be associated with MDD from available publications. Functional analysis revealed that biological processes and biochemical pathways related to neuronal development, endocrine, cell growth and/or survivals, and immunology were enriched in these genes. The pathways could be largely grouped into three modules involved in biological procedures related to nervous system, the immune system, and the endocrine system, respectively. From the MDD-specific network, 35 novel genes potentially associated with the disease were identified.

CONCLUSION

By means of network- and pathway-based methods, we explored the molecular mechanism underlying the pathogenesis of MDD at a systems biology level. Results from our work could provide valuable clues for understanding the molecular features of MDD.

Analysis of the Deleterious Single-Nucleotide Polymorphisms Associated With Antidepressant Efficacy in Major Depressive Disorder

Major depressive disorder (MDD) is a serious mental disease with negative effects on both mental and physical health of the patient. Currently, antidepressants are among the major ways to ease or treat MDD. However, the existing antidepressants have limited efficacy in treating MDD, with a large fraction of patients either responding inadequately or differently to antidepressants during the treatment. Pharmacogenetics studies have found that the genetic features of some genes are associated with the antidepressant efficacy. In order to obtain a better understanding on the relationship between the genetic factors and antidepressant treatment response, we compiled a list of 233 single-nucleotide polymorphisms (SNPs) significantly associated with the antidepressant efficacy in treating MDD. Of the 13 non-synonymous SNPs in the list, three (rs1065852, rs3810651, and rs117986340) may influence the structures and function of the corresponding proteins. Besides, the influence of rs1065852 on the structure of CYP2D6 was further investigated via molecular dynamics simulations. Our results showed that compared to the native CYP2D6 the flexibility of the F-G loop was reduced in the mutant. As a portion of the substrate access channel, the lower flexibility of F-G loop may reduce the ability of the substrates to enter the channel, which may be the reason for the lower enzyme activity of mutant. This study may help us to understand the impact of genetic variation on antidepressant efficacy and provide clues for developing new antidepressants.

Dual Roles for the TSPYL Family in Mediating Serotonin Transport and the Metabolism of Selective Serotonin Reuptake Inhibitors in Patients with Major Depressive Disorder

We previously reported that testis-specific Y-encoded-like protein (TSPYLs) are transcription regulators for CYP3A4, CYP2C9, and CYP2C19. Here, we observed dual roles for TSPYLs in mediating serotonin transport and the metabolism of selective serotonin reuptake inhibitors (SSRIs) in patients with major depressive disorder (MDD). The widely prescribed SSRIs, citalopram, and escitalopram are metabolized mainly by CYP2C19. The TSPYL1 rs3828743 single nucleotide polymorphism (SNP), which decreases its suppression of CYP2C19 expression, was associated with rapid escitalopram metabolism and worse treatment response in the Mayo PGRN-AMPS clinical trial. We also found that TSPYLs can regulate expression of the serotonin transporter protein, SLC6A4, and, in turn, serotonin transport into cells. The SNPs in tight linkage disequilibrium with the TSPYL1 rs10223646 SNP were significantly correlated with baseline severity of depression in patients with MDD in the Sequenced Treatment Alternatives to Relieve Depression and International SSRI Pharmacogenomics Consortium clinical trials. Our findings suggest that genetic variation in TSPYL genes may be novel indicators for baseline severity of depression and SSRI poor response.

Continuity of genetic and environmental influences on clinically assessed major depression from ages 18 to 45

BACKGROUND

Studies on the stability of genetic risk for depression have relied on self-reported symptoms rather than diagnoses and/or short follow-up time. Our aim is to determine to what degree genetic and environmental influences on clinically assessed major depressive disorder (MDD) are stable between age 18 and 45.

METHODS

A population-based sample of 11 727 twins (6875 women) born between 1967 and 1991 was followed from 2006 to 2015 in health registry data from primary care that included diagnoses provided by treating physicians. Individuals with schizophrenia or bipolar disorder (n = 163) were excluded. We modelled genetic and environmental risk factors for MDD in an accelerated longitudinal design.

RESULTS

The best-fitting model indicated that genetic influences on MDD were completely stable from ages 18 to 45 and explained 38% of the variance. At each age, the environmental risk of MDD was determined by the risk at the preceding observation, plus new environmental risk, with an environmental correlation of +0.60 over 2 years. The model indicated no effects of shared environment and no environmental effects stable throughout the observational period. All long-term stability was therefore explained by genetic factors.

CONCLUSIONS

Different processes unfolded in the genetic and environmental risk for MDD. The genetic component is stable from later adolescence to middle adulthood and accounted for nearly all long-term stability. Therefore, molecular genetic studies can use age-heterogenous samples when investigating genetic risk variants of MDD. Environmental risk factors were stable over a short span of years with associations rapidly decreasing and no evidence of permanent environmental scarring.

Effects of Acupuncture on Chronic Stress-Induced Depression-Like Behavior and Its Central Neural Mechanism

Depression is a serious psychiatric disorder with an enormous socioeconomic burden, and it is commonly comorbid with pain, chronic fatigue, or other inflammatory diseases. Recent studies have shown that acupuncture is an effective therapeutic method for reducing depressive symptoms; however, the underlying mechanism remains unknown. In this study, we investigated the effects of acupuncture on chronic stress-induced depression-like behavior and its central neural mechanisms in the brain. We induced chronic restraint stress (CRS) in male C57BL/6 mice for 14 or 28 consecutive days. Acupuncture treatment was performed at KI10·LR8·LU8·LR4 or control points for 7 or 14 days. Depression-like behavior was assessed with the open field test. Then, brain neural activity involving c-Fos and serotonin-related mechanisms via the 5-HT1A and 5-HT1B receptors were investigated. Acupuncture treatment at KI10·LR8·LU8·LR4 points rescued the depressive-like behavior, while control points (LU8·LR4·HT8·LR2) and non-acupoints on the hips did not. Brain neural activity was changed in the hippocampus, cingulate cortex, motor cortex, insular cortex, thalamus, and the hypothalamus after acupuncture treatment. Acupuncture treatment increased expression of 5-HT1A receptor in the cortex, hippocampus, thalamus, and the hypothalamus, and of 5-HT1B in the cortex and thalamus. In conclusion, acupuncture treatment at KI10·LR8·LU8·LR4 was effective in alleviating the depressive-like behavior in mice, and this therapeutic effect was produced through central brain neural activity and serotonin receptor modulation.

No Interaction Between Childhood Maltreatment and Serotonin Transporter Gene in Recurrent Major Depressive Disorder: A Clinical Sample

Introduction

There is inconsistent evidence of interaction between childhood adversities and a serotonin transporter promoter polymorphism (5-HTTLPR) in depression. It is hypothesized that genetic sensitivity to stress could be more specific to recurrent major depressive disorder (MDD). The aim of the study is to replicate a recent study which provided preliminary evidence of interaction between severity of childhood maltreatment and the 5-HTTLPR polymorphism in recurrent MDD.

Methods

Participants included a well-characterized clinical sample of 70 recurrent MDD cases and 67 never psychiatrically ill controls, aged 18 years or over. Socio-demographic and clinical information form, Composite International Diagnostic Interview (CIDI), Childhood Trauma Questionnaire (CTQ), Beck Depression Inventory (BDI) were applied to both groups, along with genotyping.

Results

There was no interaction between childhood maltreatment and the 5-HTTLPR in relation to recurrent MDD. All forms of childhood maltreatment were reported as more severe by cases than controls, and there was an independent association between maltreatment and recurrent MDD.

Conclusion

The path forward to detect genetic risk loci for depression remains challenging. Taking childhood maltreatment history into account could lead to a richer understanding of differences in biological correlates, genetic underpinnings, and outcomes.