Correlation between anxiety-depression symptoms and immune characteristics in inpatients with 2019 novel coronavirus in Wuhan, China

Bioinformatics Screening and Experimental Validation for Deciphering the Immune Signature of Late-Onset Depression

Background

Late-onset depression (LOD) is often associated with more severe cognitive impairment and a higher risk of disability and suicide. Emerging evidence suggests that immune system problems may be involved. This study aims to systematically characterize the genetic signature of LOD based on the immune landscape.

Methods

The expression profile of GSE76826 was obtained from the Gene Expression Omnibus (GEO) database to gather gene expression data for 10 LOD patients and 12 healthy controls (HC). Various analyses, such as Single-Sample Gene Set Enrichment Analysis (ssGSEA) and Weighted Gene Co-expression Network Analysis (WGCNA), were used to mine key genes closely related to LOD. ImmuCellAI helped us understand differences in the immune environment between LOD patients and controls, and we used an LOD animal model to validate the relevant immune characteristics.

Results

We found enriched immune pathways linked to LOD and adaptive immune responses. Using advanced bioinformatics techniques, we identified two key genes: apelin (APLN) and leptin (LEP), which have good diagnostic efficacy (AUC=0.925, 95% CI=1.00-0.83) for LOD. Neutrophil infiltration increased significantly in LOD, while CD8+ T lymphocytes (CD8_T) decreased. We finally constructed an animal model of LOD, validated two key genes and microglia marker genes in blood and hippocampus, and detected elevated pro-inflammatory factors such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α).

Conclusion

We identified and validated the presence of aberrant expression of APLN and LEP in LOD and described a possible immune mechanism involving increased release of IL-6 and TNF-α, leading to decreased CD8_T infiltration and increased neutrophil infiltration. Meanwhile, peripheral inflammation across the blood-brain barrier further promotes microglia activation, leading to neuronal damage.

Integrated Single-Cell RNA-seq and ATAC-seq Reveals Heterogeneous Differentiation of CD4+ Naive T Cell Subsets is Associated with Response to Antidepressant Treatment in Major Depressive Disorder

The mechanism involved in major depressive disorder (MDD) is well-studied but the mechanistic origin of the heterogeneous antidepressant effect remains largely unknown. Single-cell RNA-sequencing (scRNA-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) on peripheral blood mononuclear cells from 8 healthy individuals and 8 MDD patients before or after 12 weeks of antidepressant treatment is performed. scRNA-seq analysis reveals a lower proportion of naive T cells, particularly CD4+ naive T cells, in MDD patients compared to controls, and in nonresponders versus responders at the baseline. Flow cytometry data analysis of an independent cohort of 35 patients and 40 healthy individuals confirms the findings. Enrichment analysis of differentially expressed genes indicated obvious immune activation in responders. A specific activated CD4+ naive T population in responders characterized by enhanced mitogen-activated protein kinases (MAPK) pathway is identified. E-twenty six (ETS) is proposed as an upstream regulator of the MAPK pathway and heterogeneous differentiation in activated CD4+ naive T population is associated with the response to antidepressant treatment in MDD patients. A distinct immune feature manifested by CD4+ naive T cells during antidepressant treatment in MDD is identified. Collectively, this proposes the molecular mechanism that underlies the heterogeneous antidepressant outcomes for MDD.

Examining the Effect of SARS-CoV-2 Pandemic-Induced Stress and Anxiety on Humoral Immunity in Health Care Workers

OBJECTIVE

The effect of stress on vaccine-induced humoral immunity and therapeutic interventions to mitigate pandemic-related stress remain underexplored.

METHOD

Participants in a longitudinal cohort study ( n = 189) completed a validated measure, GAD-7, and 10-instrument stress measure to assess stress and anxiety after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Serum was collected to obtain SARS-CoV-2 antibody titer levels.

RESULTS

Participants experienced increased stress due to the SARS-CoV-2 pandemic with a positive correlation between GAD-7 scores and peak antibody titers overall; however, there was a negative association with scores commensurate with severe anxiety. Health care workers and younger participants were more significantly affected by anxiety.

CONCLUSIONS

Mild anxiety levels may have immune-enhancing effects, whereas severe anxiety may cause antibody generation reduction. Mental health-focused interventions are imperative for younger adults and health care workers. Young adults may be more resilient to increased stress levels.

Th17 Cells, Glucocorticoid Resistance, and Depression

Depression is a severe mental disorder that disrupts mood and social behavior and is one of the most common neuropsychological symptoms of other somatic diseases. During the study of the disease, a number of theories were put forward (monoamine, inflammatory, vascular theories, etc.), but none of those theories fully explain the pathogenesis of the disease. Steroid resistance is a characteristic feature of depression and can affect not only brain cells but also immune cells. T-helper cells 17 type (Th17) are known for their resistance to the inhibitory effects of glucocorticoids. Unlike the inhibitory effect on other subpopulations of T-helper cells, glucocorticoids can enhance the differentiation of Th17 lymphocytes, their migration to the inflammation, and the production of IL-17A, IL-21, and IL-23 in GC-resistant disease. According to the latest data, in depression, especially the treatment-resistant type, the number of Th17 cells in the blood and the production of IL-17A is increased, which correlates with the severity of the disease. However, there is still a significant gap in knowledge regarding the exact mechanisms by which Th17 cells can influence neuroinflammation in depression. In this review, we discuss the mutual effect of glucocorticoid resistance and Th17 lymphocytes on the pathogenesis of depression.

Post-COVID-19 depression and serum interleukin 6 levels: A systematic review and meta-analysis of COVID-19 convalescents with and without depression

OBJECTIVES

Depression is among the psychiatric sequelae of COVID-19, affecting more than 20% of the convalescents. Its underlying pathophysiology remains unclear. Interleukin 6 (IL-6), a pro-inflammatory cytokine, plays a critical role in the COVID-19-associated cytokine storm, has been implicated in depressive disorders, and may thus be involved in post-COVID-19 depression.

METHODS

PubMed, Scopus, Embase, and Web of Science were systematically searched for relevant studies assessing peripheral IL-6 levels in convalescents who developed depression after COVID-19 vs. convalescents who did not.

RESULTS

Five studies were included in our systematic review, and four entered the meta-analysis. The meta-analysis revealed that post-COVID people with de novo depression did not have statistically significant differences in IL-6 levels compared to those without depression (standardised mean difference (SMD) = 0.09, 95% confidence interval (CI) = -0.35, 0.54, p-value = 0.68).

CONCLUSIONS

Although convalescents with depression did not have significantly higher IL-6 levels than convalescents without depression, the results should be interpreted considering the limited sample size and the low power of the included studies.

Efficacy and safety of celecoxib monotherapy for treatment of moderate depressive symptoms following COVID-19 infection: A randomized, double-blind, placebo-controlled trial

OBJECTIVE

Celecoxib, a nonsteroidal anti-inflammatory agent, was found to be an effective add-on treatment for unipolar and bipolar depression. We investigated the potential beneficial effect of celecoxib monotherapy on depressive symptoms after Coronavirus disease (COVID-19).

METHODS

This was a randomized, double-blind, placebo-controlled clinical trial investigating the therapeutic effects of celecoxib monotherapy in patients with moderate depressive symptoms following COVID-19 infection. Patients were randomized to receive either a celecoxib capsule (100 mg) twice daily or a placebo capsule twice daily for 6 weeks. Participants were assessed with the Hamilton Depression Rating Scale (HDRS) and the side effect checklist at baseline and weeks 3 and 6.

RESULTS

A total of 62 patients were included. GLM repeated-measures showed a significant effect of time × treatment (F = 12.95, df = 1.98, p < 0.001) for celecoxib, suggesting superior improvement of depressive symptoms in celecoxib compared to placebo from baseline to the study endpoint. HDRS scores in the celecoxib group showed a greater decline from baseline to both week 3 (t = 4.12, p < 0.001, Cohen's d = 1.10) and week 6 (t = 4.76, p < 0.001, Cohen's d = 1.27), compared to the placebo group. Rate of response to treatment (70% vs 9%, p < 0.001) and remission (67% vs 0%, p < 0.001) was significantly higher in celecoxib compared to the placebo group at week 6. Adverse event frequencies were not significantly different between the two groups.

CONCLUSION

We demonstrated that treatment with celecoxib significantly improved depression scores of patients with depressive symptoms following COVID-19 infection. Further trials with larger sample sizes and longer study periods should assess our findings before any suggestion for clinical use. The trial was prospectively registered at the Iranian registry of clinical trials (www.irct.ir; registration number: IRCT20090117001556N142).

A network analysis of anxiety and depression symptoms in Chinese disabled elderly

BACKGROUND

Mental health is an essential dimension of healthy aging. The number and severity of disabled elderly in China show an increasing tendency year by year. Due to their impaired ability of daily activities, reduced social participation and reduced self-care ability, they are more prone to depression and anxiety.

METHOD

We included 2131 individuals aged 65 and older from the Chinese Longitudinal Healthy Longevity Survey (CLHLS 2017-2018). We used the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) and the Generalized Anxiety Disorder scale-7 (GAD-7) to assess depression and anxiety, respectively. The structure of depressive and anxiety symptoms was characterized using "Expected Influence" and "Bridge Expected Influence" as centrality indices in the symptom network. Network stability was tested using a case-dropping bootstrap procedure. Finally, a Network Comparison Test (NCT) was conducted to examine whether network characteristics differed by gender.

RESULTS

Network analysis revealed that nodes CESD3 (Felt sadness), GAD2 (Uncontrollable worry), and GAD4 (Trouble relaxing) were the primary symptoms of the anxiety-depression network. Anxiety and depression were united by the symptoms of CESD9 (Could not get going), GAD1 (Nervousness or anxiety), CESD10 (Sleep quality), and GAD4 (Trouble relaxing). Additionally, Gender did not significantly affect the network structure.

CONCLUSION

Central symptoms (e.g., felt sadness, uncontrollable worry and trouble relaxing) and key bridge symptoms (e.g., could not get going, nervousness and anxiety) in the depressive and anxiety symptoms network may be used as potential targets for intervention among disabled elderly who is at risk for or suffer from depressive and anxiety symptoms.

Characterization of serotonin as a candidate biomarker of severity and prognosis of COVID-19 using LC/MS analysis

The coronavirus disease 2019 (COVID-19) pandemic has been associated with high mortality worldwide. Owing to its complicated pathophysiology, diagnostic and prognostic biomarkers for effective patient management remain scarce. We analyzed kynurenine, tryptophan, and serotonin levels in the serum of patients with COVID-19 via liquid chromatography/mass spectrometry analysis. Serum serotonin levels were decreased in patients with more severe COVID-19, along with increased kynurenine and decreased tryptophan concentrations. Patients with moderate disease who subsequently worsened showed significantly lower serotonin concentrations compared with those who did not experience severe disease. Serum serotonin levels may represent a valuable biomarker for COVID-19 severity and prognosis.

Post-COVID-19 Depressive Symptoms: Epidemiology, Pathophysiology, and Pharmacological Treatment

The Coronavirus Disease 2019 (COVID-19) pandemic is still spreading worldwide over 2 years since its outbreak. The psychopathological implications in COVID-19 survivors such as depression, anxiety, and cognitive impairments are now recognized as primary symptoms of the "post-acute COVID-19 syndrome." Depressive psychopathology was reported in around 35% of patients at short, medium, and long-term follow-up after the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection. Post-COVID-19 depressive symptoms are known to increase fatigue and affect neurocognitive functioning, sleep, quality of life, and global functioning in COVID-19 survivors. The psychopathological mechanisms underlying post-COVID-19 depressive symptoms are mainly related to the inflammation triggered by the peripheral immune-inflammatory response to the viral infection and to the persistent psychological burden during and after infection. The large number of SARS-CoV-2-infected patients and the high prevalence of post-COVID-19 depressive symptoms may significantly increase the pool of people suffering from depressive disorders. Therefore, it is essential to screen, diagnose, treat, and monitor COVID-19 survivors' psychopathology to counteract the depression disease burden and related years of life lived with disability. This paper reviews the current literature in order to synthesize the available evidence regarding epidemiology, clinical features, neurobiological underpinning, and pharmacological treatment of post-COVID-19 depressive symptoms.