Epigenetics and depression

Noncoding RNAs and their influence on maternal mental health: insights into perinatal depression: a review

Perinatal depression profoundly influences the psychological and physiological well-being of women both during and after pregnancy. This condition encompasses depressive symptoms that manifest as antenatal as well as postnatal depression. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), are integral to various cellular processes and have been implicated in the pathophysiology of perinatal depression. These ncRNAs are involved in the regulation of gene expression, maintenance of neuronal function, and modulation of stress responses. Dysregulation of ncRNAs, particularly lncRNAs and miRNAs, has been associated with psychiatric disorders, including perinatal depression. This review explores the classification and functions of ncRNAs, their biological roles, and the evidence linking them to perinatal depression. The investigation of ncRNAs in the context of perinatal depression holds promise for the development of novel therapeutic strategies and the enhancement of health outcomes for both mothers and their children. Future research should prioritize the standardization of methodologies and approaches in this field.

Gamma oscillations as correlates of depression: updating Fitzgerald and Watson (2018)

Depression remains one of the most common and debilitating neuropsychiatric conditions, with little consistency in treatment efficacy. Some of the lack of success in developing effective treatments has been the absence of a reliable biomarker of depression, despite many attempts. One such potential biomarker is the electrical activity of the brain that occurs in the gamma band (30-200 Hz). To evaluate the state of research into gamma as a biomarker of depression, a review of recent research literature was conducted. A total of 31 relevant papers was identified, 22 of which used resting-state studies, and nine included a stimulus-task. These studies were examined here in terms of their definition of gamma, sample sizes, research focus, brain region examined, and EEG methodologies used. Due to the range of methodologies, some inconsistent results emerged but several valuable findings remained, including that depressed patients usually had higher gamma power than their healthy controls (HC), that the imposition of a perceptual task into the research protocol also introduced a strong element of confound to the results, and that studies that sought to evaluate the role of gamma in treatment were yet to be established as reliable. Key issues for future research are discussed, and the potential for gamma as a biomarker of depression is evaluated as emerging.

Transcriptomic Alterations in the Hippocampus and Prefrontal Cortex of Rats with Chronic Unpredictable Stress Induced by Low-Intensity Pulsed Ultrasound

In our previous study, low-intensity pulsed ultrasound stimulation (LIPUS), a novel noninvasive neuromodulation tool, effectively alleviated depression-like behaviors in a rat model of depression. However, the underlying mechanisms remain unclear. The present study aimed to elucidate the relevant mechanisms through transcriptomic research. To induce depression-like phenotypes, rats were subjected to chronic unpredictable stress (CUS) for six weeks. Following this initial stress period, LIPUS was administered daily for an additional four weeks while the rats were continuously exposed to CUS, which was previously determined to significantly reduce immobility time in forced swimming test. The transcriptome expression profiles in the hippocampus and prefrontal cortex (PFC) were subsequently analyzed by RNA sequencing techniques. Overall, LIPUS reversed the abnormal expression of genes in the brain of model rats, especially the expression of genes linked to glucose and lipid metabolism. Specifically, we found that the CUS rats exhibited 3464 differentially expressed genes (DEGs) in the hippocampus and 1781 DEGs in the PFC compared to the control group. LIPUS reversed the expression of 592 genes in the hippocampus and 254 genes in the PFC. Functional analysis revealed a significant enrichment of DEGs related to oxygen carrier activity and sugar metabolism. Subsequently, the alterations in the top ten genes were validated using real-time PCR. The significant changes in the expression of hemoglobin subunit beta, growth hormone 1, and glucokinase were confirmed. The results suggest that LIPUS may alleviate depression-related manifestations by regulating cerebral oxygenation and sugar metabolism processes in the brain.

Small non-coding RNA profiles in sperms from depressive-like mice induced by chronic unpredictable mild stimulations

Major depressive disorder (MDD) is a complex, common, and moderately heritable illness, and accumulating evidence suggests that psychological stress may affect male fertility. Mounting evidence indicates sncRNAs in sperm are sensitive to environmental changes and mediate the inheritance of paternally acquired metabolic and mental traits. In order to know the impact of psychological stress on reproduction and alterations in sperm sncRNAs, in this study, depressive-like mice induced by chronic unpredictable mild stimulation (CUMS) were used to investigate the impact of psychological stress on reproduction and alterations in sperm sncRNAs. The results showed that CUMS treatments for 4 weeks induced depressive behavior in male mice and significantly affected sperm quality. The results obtained from small RNA sequencing indicated that alterations occurred in the distribution and composition of small non-coding RNAs (sncRNAs), encompassing PIWI-interacting RNAs (piRNAs), rRNA-derived small RNAs (rsRNAs), and tRNA-derived small RNAs (tsRNAs). Furthermore, the offspring of male mice with depressive-like behavior have a significant reduction in survival rate at 21 days after birth, and those that did survive displayed an increased susceptibility to depression. This study provides some theoretical support for understanding the effects of psychological stress on reproduction, as well as information exchange from psychological stimulation to germ cells, and then from germ cells to next generation.

G9a an Epigenetic Therapeutic Strategy for Neurodegenerative Conditions: From Target Discovery to Clinical Trials

This review provides a comprehensive overview of the role of G9a/EHMT2, focusing on its structure and exploring the impact of its pharmacological and/or gene inhibition in various neurological diseases. In addition, we delve into the advancements in the design and synthesis of G9a/EHMT2 inhibitors, which hold promise not only as a treatment for neurodegeneration diseases but also for other conditions, such as cancer and malaria. Besides, we presented the discovery of dual therapeutic approaches based on G9a inhibition and different epigenetic enzymes like histone deacetylases, DNA methyltransferases, and other lysine methyltransferases. Hence, findings offer valuable insights into developing novel and promising therapeutic strategies targeting G9a/EHMT2 for managing these neurological conditions.

Probiotic Bactolac alleviates depression-like behaviors by modulating BDNF, NLRP3 and MC4R levels, reducing neuroinflammation and promoting neural repair in rat model

Depression, a prevalent psychiatric disorder, exerts severe and debilitating impacts on an individual's mental and physical well-being, and it is considered a chronic mental illness. Chronic stress plays an important role in the pathophysiology of depression. Lactobacillus plantarum and Streptococcus thermophilus are psychobiotic bacteria and synthesize some neurotransmitters that play a role in the pathogenesis of depression. In this study, we aimed to investigate the therapeutic effects of Bactolac (Lactobacillus plantarum NBIMCC 8767  + Streptococcus thermophilus NBIMCC 8258) on chronic stress-induced depression in rats. Behavioral tests, including the sucrose preference test, elevated plus maze test, forced swim test, and three-chamber sociability test, were employed to assess depressive and anxiety-like behaviors. The expression level of the 5-HT1A, DRD1, ADRA-2A, GABA-A α1, CNR1, NR3C2, NOD1, NLRP3 and MC4R; BDNF levels, glial activity and intestinal permeability were determined in chronic stress-induced depression in rats. In conclusions, chronic stress decreased the expression levels of 5-HT1A, DRD1, ADRA-2A, GABA-A α1, CNR1, NR3C2, NOD1 and BDNF level; increased the expression levels of NLRP3 and MC4R, caused neurodegeneration and glial activity, ultimately led to depressive effects. Bactolac was effective in reducing depressive-like behaviors according to the results of behavioral tests. Bactolac treatment provided high neuronal survival rate increasing BDNF level, prevented the excessive release of pro-inflammatory cytokines by reducing the expression levels of NLRP3 and MC4R, therefore, prevented the excessive activation of the hypothalamus-pituitary-adrenal (HPA) axis and accordingly, reduced neurodegeneration and glial cell activation in depressed rats. We can suggest that Bactolac supplementation may be beneficial in coping with stress, alleviate the effects of chronic stress and help to protect mental health.

Hippocampal microRNA-181a overexpression participates in anxiety and ethanol related behaviors via regulating the expression of SIRT-1

Understanding the molecular mechanisms underlying anxiety and ethanol-related behaviors is crucial for developing effective therapeutic interventions. This study identifies a novel role for microRNA miR-181a and its target, Sirtuin 1 (SIRT-1), in the hippocampus as contributors to anxiety-like behavior and voluntary ethanol intake. Using male and female C57BL/6 mice, we explored the causal relationship between hippocampal miR-181a expression and these behaviors. Lentivirus vectors were delivered into the hippocampus for focal miR-181a overexpression in mice. Then behaviors were observed by elevated plus maze (EPM) and open field (OF) tests. Results showed that the viral approach employed to overexpress miR-181a, in the hippocampus, resulted in increased anxiety-like behavior in the EPM and OF tests. Additionally, miR-181a overexpression exacerbated voluntary ethanol intake and preference in the two-bottle choice paradigm without affecting saccharin or quinine consumption. Mechanistically, miR-181a gain-of-function reduced SIRT-1 expression in the hippocampus. These findings demonstrate that miR-181a upregulation in the hippocampus promotes anxiety and ethanol-related behaviors, likely through SIRT-1 repression. This work highlights miR-181a as a key molecular mediator in the epigenetic regulation of mood disorders and ethanol consumption.

Persister Intestinal Bacteria, Epigenetics and Major Depression

The microbiota-gut-brain axis has been proposed as a potential modulator of mood disorders such as major depression. Complex bidirectional biochemical activities in this axis have been posited to participate in adverse mood disorders. Environmental and genetic factors have dominated recent discussions on depression. The prescription of antibiotics, antidepressants, adverse negative DNA methylation reactions and a dysbiotic gut microbiome have been cited as causal for the development and progression of depression. While research continues to investigate the microbiome-gut-brain axis, this review will explore the state of persistence of gut bacteria that underpins bacterial dormancy, possibly due to adverse environmental conditions and/or pharmaceutical prescriptions. Bacterial dormancy persistence in the intestinal microbial cohort could affect the role of bacterial epigenomes and DNA methylations. DNA methylations are highly motif driven exerting significant control on bacterial phenotypes that can disrupt bacterial metabolism and neurotransmitter formation in the gut, outcomes that can support adverse mood dispositions.

Parental psychiatric disorders and age-specific risk for offspring major depression: Finnish nationwide register-based study

BACKGROUND

Limited studies have examined the association between the whole range of parental psychopathology and offspring major depression (MD). No previous study has examined this association by age of onset of offspring MD, or restricting to parental psychiatric diagnoses before offspring birth.

METHODS

This nested case-control study included 37,677 cases of MD and 145,068 controls, identified from Finnish national registers. Conditional logistic regression models examined the association between parental psychopathology and MD, adjusting for potential confounders.

RESULTS

Increased risk of MD, expressed as adjusted odds ratio and 95% confidence interval (aOR [95% CI]) were most strongly observed for maternal diagnoses of schizophrenia and schizoaffective disorders (2.51 [2.24-2.82]) and depression (2.19 [2.11-2.28]), and paternal diagnoses of schizophrenia and schizoaffective disorders (2.0 [1.75-2.29]) and conduct disorders (1.90 [1.40-2.59]). The aORs for any psychiatric diagnosis were (2.66 [2.54-2.78]) for mothers, (1.95 [1.86-2.04]) for fathers, and (4.50 [4.24-4.79]) for both parents. When both parents had any psychiatric diagnosis, the highest risk was for MD diagnosed at the age of 5-12 years (7.66 [6.60-8.89]); versus at 13-18 years (4.13 [3.85-4.44]) or 19-25 years (3.37 [2.78-4.07]). A stronger association with parental psychopathology and offspring MD was seen among boys than girls, especially among 13-19 years and 19-25 years.

CONCLUSIONS

Parental psychiatric disorders, including those diagnosed before offspring birth, were associated with offspring MD, indicating potential genetic and environmental factors in the development of the disorder.

The minor allele of the serotonin transporter gene variant rs4251417 is associated with increased resilience in soldiers experiencing acute stress during survival training: preliminary findings

BACKGROUND

Variation in cognitive, emotional and physical performance in response to stress is attributable to environmental and genetic factors. Ability to adapt to stress is resilience.

OBJECTIVES

This study investigated genetic factors associated with resilience in soldiers exposed to severe stress due to intense physical and mental demands at Survive, Evade, Resist and Escape school, a unique environment to study acute stress and resiliency in real-world circumstances.

DESIGN

A preliminary correlational study was conducted to identify genetic markers for resilience to stress.

METHODS

Mood state, resiliency and dissociative state of 73 soldiers were assessed using: Connor-Davidson Resilience Scale (CD-RISC); Profile of Mood States (POMS); and Clinician-Administered Dissociative States Scale (CADSS). Change scores for resilience-related stress markers were computed; 116 single nucleotide polymorphisms (SNPs) associated with stress, depression, anxiety, sleep, or psychiatric disorders were assessed.

RESULTS

A significant association between change in CD-RISC score and SNP rs4251417, present in an intron of SLC6A4, the serotonin transporter gene, was observed.

CONCLUSIONS

Individuals with the minor allele of SNP rs4251417 had a greater positive change in CD-RISC, indicating increased self-assessed resilience. This study suggests the minor allele of SNP rs4251417 of SLC6A4 is associated with resilience when individuals are exposed to high stress.

Using multiomic integration to improve blood biomarkers of major depressive disorder: a case-control study

BACKGROUND

Major depressive disorder (MDD) is a leading cause of disability, with a twofold increase in prevalence in women compared to men. Over the last few years, identifying molecular biomarkers of MDD has proven challenging, reflecting interactions among multiple environmental and genetic factors. Recently, epigenetic processes have been proposed as mediators of such interactions, with the potential for biomarker development.

METHODS

We characterised gene expression and two mechanisms of epigenomic regulation, DNA methylation (DNAm) and microRNAs (miRNAs), in blood samples from a cohort of individuals with MDD and healthy controls (n = 169). Case-control comparisons were conducted for each omic layer. We also defined gene coexpression networks, followed by step-by-step annotations across omic layers. Third, we implemented an advanced multiomic integration strategy, with covariate correction and feature selection embedded in a cross-validation procedure. Performance of MDD prediction was systematically compared across 6 methods for dimensionality reduction, and for every combination of 1, 2 or 3 types of molecular data. Feature stability was further assessed by bootstrapping.

FINDINGS

Results showed that molecular and coexpression changes associated with MDD were highly sex-specific and that the performance of MDD prediction was greater when the female and male cohorts were analysed separately, rather than combined. Importantly, they also demonstrated that performance progressively increased with the number of molecular datasets considered.

INTERPRETATION

Informational gain from multiomic integration had already been documented in other medical fields. Our results pave the way toward similar advances in molecular psychiatry, and have practical implications for developing clinically useful MDD biomarkers.

FUNDING

This work was supported by the Centre National de la Recherche Scientifique (contract UPR3212), the University of Strasbourg, the Université Sorbonne Paris Nord, the Université Paris Cité, the Fondation de France (FdF N° Engt:00081244 and 00148126; ECI, IY, RB, PEL), the French National Research Agency (ANR-18-CE37-0002, BE, CMC, ADD, PEL, ECI; ANR-18-CE17-0009, ADD; ANR-19-CE37-0010, PEL; ANR-21-RHUS-009, ADD, BE, CMC, CCB; ANR-22-PESN-0013, ADD), the Fondation pour la Recherche sur le Cerveau (FRC 2019, PEL), Fondation de France (2018, BE, CMC, ADD) and American Foundation for Suicide Prevention (AFSP YIG-1-102-19; PEL).

A novel insight into the antidepressant effect of cannabidiol: possible involvement of the 5-HT1A, CB1, GPR55, and PPARγ receptors

BACKGROUND

Depression is a prevalent and disabling disorder that poses serious problems in mental health care, and rapid antidepressants are novel treatments for this disorder. Cannabidiol (CBD), a nonintoxicating phytocannabinoid, is thought to have therapeutic potential due to its important neurological and anti-inflammatory properties. Despite major advances in pharmacotherapy in experimental animals, the exact mechanism of antidepressant-like effects remains to be elucidated.

METHODS

In this paper, we review the current state of knowledge on the antidepressant properties of CBD in numerous experimental and clinical studies.

RESULTS

Accumulating evidence suggests that CBD has antidepressant properties in humans and animals with few side effects, suggesting that CBD may be a potential antidepressant. Furthermore, we discuss that CBD may therefore provide a potential treatment to exert antidepressant-like effects through various molecular targets, reducing inflammation, and enhancing neurogenesis.

CONCLUSIONS

Taken together with the growing popularity of CBD as a medicine, these findings extend the limited knowledge on the antidepressant effects of CBD. This potentially opens up new therapeutic means for the patients with depression.

MicroRNA signatures in neuroplasticity, neuroinflammation and neurotransmission in association with depression

Depression is a multifactorial disorder that occurs mainly on account of the dysregulation of neuroplasticity, neurotransmission and neuroinflammation in the brain. In addition to environmental /lifestyle factors, the pathogenesis of disease has been associated with genetic and epigenetic factors that affect the reprogramming of normal brain function. MicroRNA (miRNAs), a type of non-coding RNAs, are emerging as significant players that play a vital role in the regulation of gene expression and have been extensively explored in neurodegenerative disorders. Recent studies have also shown the role of gut microbiota that forms a complex bidirectional network with gut brain axis, impacting neuroinflammation in case of Parkinson's disease and depression. Translating targeted miRNA-based therapies for the treatment of neurological disorders including depression, into clinical practice remains challenging due to the ineffective delivery of the therapeutic molecules and off-target effects of the specific miRNAs. This review provides significant insights into how miRNAs are emerging as vital players in the development of depression, especially the ones involved in three important processes including neuroplasticity, neurotransmission and neuroinflammation. In this review, the current status of miRNAs as biomarkers for therapeutic interventions in the case of depression has been discussed along with an overview of future perspectives, like use of nanotechnology and gene editing, keeping in view other multifactorial disorders where such interventions by mimics and inhibitors have already reached clinical trials. The challenges for targeting the specific miRNAs for therapeutic outcomes have also been highlighted.

Electrochemical biosensors for depression: Diagnosis and therapeutic monitoring

Electrochemical biosensors have revolutionized the detection of biomarkers related to depression and the quantification of antidepressant drugs. These biosensors leverage nanomaterials and advanced assay designs to achieve high sensitivity and selectivity for clinically relevant analytes. Key neurotransmitters implicated in depression, such as serotonin, dopamine, and glutamate, can be accurately measured via biosensors, providing insights into the effects of antidepressant treatments on neurotransmission. Biosensors can also detect biomarkers of inflammation, oxidative stress, and neuronal health that are altered in depression. Real-time biosensing techniques such as fast-scan cyclic voltammetry enable monitoring of dynamic neurotransmitter changes during depressive episodes and pharmacological interventions. Advancements incorporating graphene, gold nanoparticles, and other nanomaterials have enhanced biosensor performance, enabling the detection of low biomarker concentrations. Closed-loop biosensing systems hold promise for precision medicine by automating antidepressant dosage adjustments on the basis of neurotransmitter levels. A wide range of depression biomarkers, including apolipoprotein A4, heat shock protein 70, brain-derived neurotrophic factor, microRNAs, proteins, and combinatorial biomarker panels, have been detected via sophisticated biosensor platforms. Emerging biosensors show selectivity for antidepressant drugs such as serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and selective serotonin reuptake inhibitors in biological samples. This review emphasizes the transformative potential of electrochemical biosensors in combating depression. By facilitating earlier and more accurate diagnoses, these biosensors can revolutionize patient care and enhance treatment outcomes.

Investigating the Gene Relation Between Cervical Spondylosis and Depression: Bidirectional Mendelian Randomization Study

Background

Previous observational studies have suggested a potential link between depression and cervical spondylosis (CS). While it is known that depression and CS can coexist, the specific relationship between them is not fully understood. We hypothesize that there may be connections between the two conditions, but the independent causal relationship of depression as a risk factor for CS, remains uncertain. This particular study has important implications for the future clinical treatment of depression and cervical spondylosis because Mendelian randomization has not been widely used in this field. We obtained valuable results through big data analysis and have guiding significance for future research.

Methods

We conducted a two-sample Mendelian randomization (MR) study using data from genome-wide association studies to investigate the causal relationship between depression and CS in individuals of European ancestry. Additionally, we examined the impact of CS on susceptibility to depression using large population-level genetic data (number of depression SNPs: 9,761,853; number of CS SNPs: 9,851,867). The primary approach for data analysis was the inverse-variance weighted (IVW) method to estimate potential causal effects. Furthermore, we performed sensitivity analyses utilizing methods such as Manhattan plot (CMplot), linkage disequilibrium (LD), F-filtering, removal of phenoscanner, MR-Egger, weighted median, MR-PRESSO simple mode weighted mode MR pleiotropy test MR heterogeneity assessment leave-one-out analysis to ensure result robustness.

Results

Our findings indicated that an elevated likelihood of CS was linked to depression [IVW odds ratio (OR): 1.322, 95% confidence interval (CI): 1.205-1.441, P=0.01243]. There was reciprocal evidence of causation, with the genetic predisposition to depression significantly heightening susceptibility to CS [IVW odds ratio (OR): 1.426, 95% confidence interval (CI): 1.236-1.651, P=0.01775].

Conclusion

This investigation provides genetic support for a bidirectional causal association between depression and CS. Specifically, individuals with depression are at greater risk of developing CS. Addressing depression may serve as an effective approach in mitigating or preventing the burden of CS and vice versa.

The combination of decitabine with multi-omics confirms the regulatory pattern of the correlation between DNA methylation of the CACNA1C gene and atrial fibrillation

Background

Studies have shown that DNA methylation of the CACNA1C gene is involved in the pathogenesis of various diseases and the mechanism of drug action. However, its relationship with atrial fibrillation (AF) remains largely unexplored.

Objective

To investigate the association between DNA methylation of the CACNA1C gene and AF by combining decitabine (5-Aza-2'-deoxycytidine, AZA) treatment with multi-omics analysis.

Methods

HepG2 cells were treated with AZA to observe the expression of the CACNA1C gene, which was further validated using gene expression microarrays. Pyrosequencing was employed to validate differentially methylated sites of the CACNA1C gene observed in DNA methylation microarrays. A custom DNA methylation dataset based on the MSigDB database was combined with ChIP-sequencing and RNA-sequencing data to explore the regulatory patterns of DNA methylation of the CACNA1C gene.

Results

Treatment of HepG2 cells with three different concentrations of AZA (2.5 µM, 5.0 µM, and 10.0 µM) resulted in 1.6, 2.5, and 2.9-fold increases in the mRNA expression of the CACNA1C gene, respectively, compared to the DMSO group, with statistical significance at the highest concentration group (p < 0.05). Similarly, AZA treatment of T47D cells showed upregulated mRNA expression of the CACNA1C gene in the gene expression microarray results (adj P < 0.05). DNA methylation microarray analysis revealed that methylation of a CpG site in intron 30 of the CACNA1C gene may be associated with AF (adj P < 0.05). Pyrosequencing of this site and its adjacent two CpG sites demonstrated significant differences in DNA methylation levels between AF and sinus rhythm groups (p < 0.05). Subsequent multivariate logistic regression models confirmed that the DNA methylation degree of these three sites and their average was associated with AF (p < 0.05). Additionally, the UCSC browser combined with ChIP-sequencing revealed that the aforementioned region was enriched in enhancer markers H3K27ac and H3K4me1. Differential expression and pathway analysis of RNA-sequencing data ultimately identified ATF7IP and KAT2B genes as potential regulators of the CACNA1C gene.

Conclusion

The DNA methylation levels at three CpG sites in intron 30 of the CACNA1C gene are associated with AF status, and potentially regulated by ATF7IP and KAT2B.

Phytochemicals in the treatment of patients with depression: a systemic review

Background

Depression is a complex mental disease whose incidence increases every year; 300 million people worldwide currently suffer from it. Women are more likely to suffer from depression, twice the rate as men. It is one of the few illnesses that can lead to suicide, which makes it very dangerous - currently, 700,000 people die from suicide and it is the 4th most common cause of death in people aged 15-29. The treatment strategies for depression is a big challenge for physicians, pharmacists, scientists and classic remedies cause many side effects. Therefore, natural phytotherapy with herbs can prove to be a good solution. Phytotherapy is a popular treatment method used for centuries in Chinese medicine or Ayurveda.

Materials and methods

The study conducted a comprehensive database search PubMed, ClinicalKey and MedNar covered the years 2015 - 2024 to provide the most up-to-date data. 13 randomized controlled trials and 1 meta - analysis were included in the systematic review.

Results

Many plants show anti-inflammatory, antioxidant and cognitive enhancing effects, which are particularly important in depression. In the treatment of depression, plants such as Crocus sativus L. stigma, Lavandula angustifolia, Hypericum perforatum L. and Curcuma longa L. have proven to be effective. They show good effectiveness in human studies and alleviate the symptoms of depression. Herbal products can support classical pharmacotherapy, but this requires further research. Non-commercial clinical trials in the future should provide answers to research questions: at what stage of treatment of patients with MDD will the use of phytochemicals be most appropriate in terms of therapy efficacy and safety for the patient.

Conclusions

Crocus sativus L. stigma, Lavandula angustifolia, Hypericum perforatum L. and Curcuma longa L. in modern medicine can help improve the well-being of patients with depression. The use of herbs as an intervention was associated with a decrease in the concentration of proinflammatory cytokines and an overall improvement in the mood of patients. Further research should be undertaken into combining both therapies in order to improve patients' quality of life and reduce treatment costs.

PRKCB methylation: a potential biomarker of MDD with childhood chronic stress, a cross-sectional study in drug-naive, first-episode adolescent MDD

The purpose of this study was to investigate the relationship between childhood chronic stress(CCS), Protein kinase C beta (PRKCB) methylation and adolescent major depressive disorder (MDD). After recruiting 100 adolescents with MDD and 50 healthy controls (HCs), we evaluated the severity of CCS. PRKCB methylation was assessed by pyrosequencing using whole blood-derived DNA. To explore the relationship between CCS, PRKCB and adolescent MDD, we conducted correlation analysis and regression analysis, and constructed multiplicative interaction models and generalized linear models. PRKCB methylation and CCS were both found to be associated with MDD, and CCS was associated with PRKCB methylation. No significant CCS-PRKCB methylation interactions were observed. However, we found the interaction of CCS and MDD on PRKCB methylation. Our results found that PRKCB methylation was influenced by CCS and the disease itself, and PRKCB methylation was significantly positively associated with MDD severity, suggesting that PRKCB methylation may be a potential biomarker for adolescent MDD. This study is a cross-sectional observational study, which cannot draw the conclusion of causality. Prospective cohort studies are needed to further examine the relationship between CCS, adolescent MDD, and PRKCB methylation.

Epigenetic alterations in patients with anorexia nervosa-a systematic review

Anorexia nervosa (AN) is a complex metabolic and psychological disorder that is influenced by both heritable genetic components and environmental factors. Exposure to various environmental influences can lead to epigenetically induced changes in gene expression. Epigenetic research in AN is still in its infancy, and studies to date are limited in determining clear, valid links to disease onset and progression are limited. Therefore, the aim of this systematic review was to compile and critically evaluate the available results of epigenetic studies specifically in AN and to provide recommendations for future studies. In accordance with the PRISMA guidelines, a systematic literature search was performed in three different databases (PubMed, Embase, and Web of Science) through May 2023. Twenty-three original papers or conference abstracts on epigenetic studies in AN were collected. Epigenome-wide association studies (EWASs), which analyze DNA methylation across the genome in patients with AN and identify potential disease-relevant changes in promoter/regulatory regions of genes, are the most promising for future research. To date, five EWASs on AN have been published, suggesting a potential reversibility of malnutrition-induced epigenetic changes once patients recover. Hence, determining differential DNA methylation levels could serve as a biomarker for disease status or early diagnosis and might be involved in disease progression or chronification. For future research, EWASs with a larger sample size, longitudinal study design and uniform methods should be performed to contribute to the understanding of the pathophysiology of AN, the development of individual interventions and a better prognosis for affected patients.

Enriched H3K27Me3 on BMP4 suppresses the osteoblastic differentiation potential of BMSCs in diabetes mellitus

Diabetes mellitus has been widely acknowledged to have a negative effect on the osteoblastic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). However, the underlying epigenetic mechanisms associated with this process remain to be elucidated. The goal of the present study was to investigate the effect of diabetes mellitus on the osteoblastic differentiation of BMSCs and assess the role of histone methylation in the observed phenomena. The osteoblastic differentiation ability of BMSCs was shown to be decreased in diabetes mellitus, as indicated by alkaline phosphatase activity and the mRNA levels of osteoblast-related genes. Furthermore, diabetes mellitus caused an increased expression of the histone methylase EZH2 and the levels of H3K27Me3 and decreased the expression of the histone demethylase KDM6B, as demonstrated by qRT-PCR and western blotting. Furthermore, immunofluorescence staining suggested that both EZH2 and H3K27Me3 were primarily localized in the nucleus. In addition, chromatin immunoprecipitation assays indicated an increased presence of H3K27Me3 on the promoter region of the BMP4 gene. In summary, in the present study, we demonstrated that the osteoblastic differentiation of BMSCs is dramatically reduced in diabetes mellitus. In addition, upregulation of EZH2 expression and downregulation of KDM6B expression may not be enough to eliminate transcriptional repression mediated by H3K27Me3 on the promoter region of the BMP4 gene during the osteoblastic differentiation of BMSCs in diabetes mellitus.

The effect of vitamin D supplementation on depression: a systematic review and dose-response meta-analysis of randomized controlled trials

The impact of vitamin D supplementation on depressive symptoms remains uncertain. This study aimed to investigate the dose-dependent effects of vitamin D supplementation on depressive and anxiety symptoms in adults. We systematically searched PubMed, Scopus, and Web of Science up to December 2022 to identify randomized controlled trials evaluating the effects of vitamin D3 supplementation on depression and anxiety symptoms in adults. Using a random-effects model, we calculated the standardized mean difference (SMD) for each 1000 IU/day vitamin D3 supplementation. The GRADE tool assessed the certainty of evidence. Our analysis included 31 trials with 24189 participants. Each 1000 IU/day vitamin D3 supplementation slightly reduced depressive symptoms in individuals with and without depression (SMD: -0.32, 95% CI -0.43 to -0.22; GEADE = moderate). The effect was more pronounced in those with depressive symptoms (SMD: -0.57, 95% CI -0.69 to -0.44; n = 15). The greatest reduction occurred at 8000 IU/day (SMD: -2.04, 95% CI -3.77 to -0.31). Trials with follow-up ⩽8 weeks (SMD: -0.45, 95% CI -0.70 to -0.20; n = 8) and 8 to ⩽24 weeks (SMD: -0.47, 95% CI -0.70 to -0.24; n = 15) showed stronger effects compared to those lasting 24 to ⩽52 weeks (SMD: -0.13, 95% CI -0.28 to 0.02; n = 5) or longer than 52 weeks (SMD: 0.14, 95% CI -0.16 to 0.44; n = 3) (p group difference <0.001). Vitamin D3 supplementation had no significant effects on anxiety symptoms. In summary, this study suggests that vitamin D3 supplementation may effectively reduce depressive symptoms in short term. Further high-quality trials are warranted for a conclusive assessment of its impact on anxiety.

Inhibition of HMOX1 by MAFG potentiates the development of depression‑like behavior in mice associated with astrocyte-mediated neuroinflammation

MAF bZIP transcription factor G (MAFG)-driven astrocytes have been reported to promote inflammation in the CNS. However, its function in depression, the primary cause of disability worldwide, has not been well characterized. This study investigated the possible perturbation of heme oxygenase 1 (HMOX1, also known as HO1) by the transcription factor MAFG as an underlying mechanism of the development of depression. The GSE98793 dataset was included for gene expression analysis of whole blood from donors with major depressive disorder and controls, and the target of MAFG was predicted by multiple database mining. Mouse and cellular models of depression were established by chronic unpredictable mild stress (CUMS) and lipopolysaccharide (LPS) treatment of astrocytes, which were treated with MAFG and HMOX1 knockdown plasmids. MAFG was highly expressed in the hippocampal tissues of CUMS-challenged mice and LPS-induced astrocytes. MAFG knockdown alleviated depression-like behaviors in mice. MAFG bound to the HMOX1 promoter and repressed its transcription. Knockdown of HMOX1 exacerbated neuroinflammation in astrocytes and accelerated depression-like behavior in mice. In conclusion, MAFG knockdown attenuated CUMS-stimulated depression-like behaviors in mice by astrocyte-mediated neuroinflammation via restoration of HMOX1.

Relationship Between the Occurrence of Depression and DROSHA (rs6877842, rs10719) and XPO5 (rs11077) Single-Nucleotide Polymorphisms in the Polish Population: A Case-Control Study

Although the epidemiology and symptoms of major depressive disorder (MDD) have been well-documented, the etiology and pathophysiology of the disease have not yet been fully explained. Depression arises from intricate interplay among social, psychological, and biological factors. Recently, there has been growing focus on the involvement of miRNAs in depression, with suggestions that abnormal miRNA processing locally at the synapse contributes to MDD. Changes in miRNAs may result from altered expression and/or function of the miRNA biogenesis machinery at the synapse. The aim of our research was to assess the relationship between the occurrence of depression and single-nucleotide polymorphisms (SNP) in the following genes in the Polish population: DROSHA (rs6877842; rs10719) and XPO5 (rs11077). This study involved 200 individuals, including 100 with depressive disorders in the study group (SG) and 100 healthy people without MDD in the control group (CG). All participants were unrelated native Caucasian Poles from central Poland. Blood samples were collected to evaluate the single-nucleotide polymorphism of the genes. Findings indicated that within our patient cohort, the risk of depression is increased by polymorphic variants of the rs10719/DROSHA and rs11077/XPO5 genes and lowered by rs6877842/DROSHA. Our study sheds light on the understanding of the genetic basis of depression, which can be used in the rapid diagnosis of this disease.

Normative implications of postgenomic deterministic narratives: the case study of epigenetic harm

What do we mean when we talk about epigenetic harm? This paper presents a multidimensional view of epigenetic harm. It is a plea to take a step back from discussions of epigenetic responsibility distributions prevalent in ELSA literature on epigenetics. Instead, it urges researchers to take a closer look at the normative role played by the concept of epigenetic harm. It starts out by showing that the ways in which the object of epigenetic responsibility has already been conceptualized are all related to 'epigenetic harm': something negative that happens in which epigenetic mechanisms play a role, or rather something that needs to be avoided. Epigenetic harm is then characterized as a bridging concept between relatively neutral findings on epigenetics on the one side, and potential ethical and societal implications of those findings, primarily in terms of responsibility ascriptions and distributions, on the other. The paper proposes that a sufficiently nuanced account of epigenetic harm should include at least three dimensions. The dimension of causation alone leads to an overly narrow understanding of harm, and a wrong understanding of this dimension might prompt researchers to support an excessively simplistic epigenetic determinism. It is argued that a multidimensional analysis of epigenetic harm is less vulnerable to this threat and more reflective of the various kinds of harm that may be experienced by the subjects of epigenetic alterations. The paper applies insights from disability studies and feminist philosophy to draw attention to two other dimensions of epigenetic harm, namely lived experiences and relationality. The paper concludes by exploring what a shift towards a multidimensional approach to epigenetic harm might mean for epigenetic research and responsibility ascriptions by formulating some concrete implications.

Advances of curcumin in nervous system diseases: the effect of regulating oxidative stress and clinical studies

In recent years, researchers have highly observed that neurological disorders (NSDs) with the aging of the population are a global health burden whose prevalence is increasing every year. Previous evidence suggested that the occurrence of neurological disorders is correlated with predisposing factors such as inflammation, aging, and injury. Particularly, the neuronal cells are susceptible to oxidative stress, leading to lesions caused by high oxygen-consuming properties. Oxidative stress (OS) is a state of peroxidation, which occurs as a result of the disruption of the balance between oxidizing and antioxidizing substances. The oxidative intermediates such as free radicals, hydrogen peroxide (H2O2), and superoxide anion (O2-) produced by OS promote disease progression. Curcumin, a natural diketone derived from turmeric, is a natural antioxidant with a wide range of neuroprotective, anti-inflammatory, anti-tumor, anti-aging, and antioxidant effects. Fortunately, curcumin is recognized for its potent antioxidant properties and is considered a promising candidate for the prevention and treatment of neurological diseases. Consequently, this review elucidates the mechanisms by which curcumin mitigates oxidative stress and emphasizes the potential in treating nervous system disorders, including depression, Alzheimer's disease, Parkinson's disease, epilepsy, subarachnoid hemorrhage, and glioblastoma. We aim to provide a new therapeutic option for the management of neurological diseases.

Childhood emotional maltreatment affects depression of adolescents with mood disorders: the mediating role of functions of non-suicidal self-injury

BACKGROUND

Childhood emotional maltreatment, non-suicidal self-injury and depression are prevalent among adolescents with mood disorders. While existing model indicated that childhood emotional maltreatment, functions of non-suicidal self-injury and depression are interrelated, not much is understood about the interplay of functions of non-suicidal self-injury in the relationship between childhood emotional maltreatment and depression. Thus, the goal of this research was to ascertain how functions of non-suicidal self-injury relate to childhood emotional maltreatment and depression.

METHODS

The participants were adolescents with mood disorders from three hospitals in Sichuan Province, data was collected using self-administered questionnaires, including the Childhood Trauma Questionnaire, Ottawa Self-injury Inventory-Functions, and Childhood Depression Inventory. SPSS26.0 software and PROCESS v3.3 model 4 were used for analysis.

RESULTS

In all, 235 adolescents (Mage=14.8, SD = 1.62) participated in the research. The functions of non-suicidal self-injury (r = 0.289, P < 0.01) and depression (r = 0.475, P < 0.01) were considerably positively connected with childhood emotional maltreatment, and the functions of non-suicidal self-injury were strongly positively correlated with depression (r = 0.364, P < 0.01). The direct impact of childhood emotional maltreatment on depression in adolescents was found to be significant (95% CI 0.434, 0.828) in the mediated effects model. Additionally, the indirect effect of childhood emotional maltreatment on depression through functions of non-suicidal self-injury was found to be significant (95% CI 0.055, 0.236), with a mediating effect value of 17.58%.

CONCLUSION

Childhood emotional maltreatment has a direct impact on depression, but it also has an indirect influence through mediation roles of functions of non-suicidal self-injury. Medical staff should take care of the mental health of adolescents hospitalized for mood disorders so that they can clarify the role of functions of NSSI in lowering depressive symptoms and improving quality of life and create more targeted and effective intervention plans.

Deciphering the role of miRNA-134 in the pathophysiology of depression: A comprehensive review

This study summarizes the significance of microRNA-134 (miRNA-134) in the pathophysiology, diagnosis, and treatment of depression, a disease still under investigation due to its complexity. miRNA-134 is an endogenous short non-coding RNA that can bind to the 3' untranslated region (3'UTR) of miRNA-134, inhibiting gene translation and showing great potential in the regulation of mood, synaptic plasticity, and neuronal function. This study included 15 articles retrieved from four English-language databases: PubMed, Embase, The Cochrane Library, and Web of Science, and three Chinese literature databases: CNKI, Wanfang, and Chinese Science and Technology Periodical Database (VIP).We evaluated each of the 15 articles using the Critical Appraisal Skills Program (CASP) tool.The standard integrates analyzes of genomic, transcriptomic, neuroimaging, and behavioral data analyses related to miRNA-134 and depression. A multidimensional framework based on standardized criteria was used for quality assessment. The main findings indicate that miRNA-134 significantly affects synaptic plasticity and neurotransmitter regulation, in particular the synthesis and release of serotonin and dopamine. miRNA-134 shows high sensitivity and specificity as a biomarker for the diagnosis of depression and has therapeutic potential for the targeted treatment of depression. miRNA-134 plays a crucial role in the pathogenesis of depression, providing valuable insights for early diagnosis and the development of targeted therapeutic strategies. This work highlights the potential of miRNA-134 as a focal point for advancing personalized medicine approaches for depression.

Identification and experimental validation of hub genes underlying depressive-like behaviors induced by chronic social defeat stress

Introduction: Major depressive disorder (MDD), characterized by severe neuropsychiatric symptoms and significant cognitive deficits, continues to present both etiological and therapeutic challenges. However, the specific underlying mechanisms and therapeutic targets remain unclear. Methods: We analyzed human postmortem dorsolateral prefrontal cortex (dlPFC) samples from MDD patients using datasets GSE53987 and GSE54568, identifying three key genes: AGA, FBXO38, and RGS5. To model depressive-like behavior, we employed chronic social defeat stress (CSDS) and subsequently measured the expression of AGA, FBXO38, and RGS5 in the dlPFC using qPCR and Western blot analysis following CSDS exposure. Results: CSDS significantly induced depressive-like behavior, and both the protein and transcriptional expression levels of AGA, FBXO38, and RGS5 in the dlPFC of mice were markedly reduced after stress, consistent with findings from datasets GSE53987 and GSE54568. Conclusion: Our research suggests that AGA, FBXO38, and RGS5 are potential biomarkers for MDD and could serve as valuable targets for MDD risk prediction.

Investigating the Epigenetic Landscape of Major Depressive Disorder: A Genome-Wide Meta-Analysis of DNA Methylation Data, Including New Insights into Stochastic Epigenetic Mutations and Epivariations

Background/Objectives: Major depressive disorder (MDD) is a mental health condition that can severely impact patients' social lives, leading to withdrawal and difficulty in maintaining relationships. Environmental factors such as trauma and stress can worsen MDD by interacting with genetic predispositions. Epigenetics, which examines changes in gene expression influenced by the environment, may help identify patterns linked to depression. This study aimed to explore the epigenetic mechanisms behind MDD by analysing six public datasets (n = 1125 MDD cases, 398 controls in blood; n = 95 MDD cases, 96 controls in brain tissues) from the Gene Expression Omnibus. Methods: As an innovative approach, two meta-analyses of DNA methylation patterns were conducted alongside an investigation of stochastic epigenetic mutations (SEMs), epigenetic age acceleration, and rare epivariations. Results: While no significant global methylation differences were observed between MDD cases and controls, hypomethylation near the SHF gene (brain-specific probe cg25801113) was consistently found in MDD cases. SEMs revealed a gene-level burden in MDD, though epigenetic age acceleration was not central to the disorder. Additionally, 51 rare epivariations were identified in blood tissue and 1 in brain tissue linked to MDD. Conclusions: The study emphasises the potential role of rare epivariations in MDD's epigenetic regulation but calls for further research with larger, more diverse cohorts to confirm these findings.

Recent developments in intranasal drug delivery of nanomedicines for the treatment of neuropsychiatric disorders

Neuropsychiatric disorders are multifaceted syndromes with confounding neurological explanations. It includes anxiety, depression, autism spectrum disorder, attention deficit hyperactivity disorder, schizophrenia, Tourette's syndrome, delirium, dementia, vascular cognitive impairment, and apathy etc. Globally, these disorders occupy 15% of all diseases. As per the WHO, India has one of the largest populations of people with mental illnesses worldwide. The blood-brain barrier (BBB) makes it extremely difficult to distribute medicine to target cells in the brain tissues. However, it is possible through novel advancements in nanotechnology, molecular biology, and neurosciences. One such cutting-edge delivery method, nose-to-brain (N2B) drug delivery using nanoformulation (NF), overcomes traditional drug formulation and delivery limitations. Later offers more controlled drug release, better bioavailability, improved patient acceptance, reduced biological interference, and circumvention of BBB. When medicines are delivered via the intranasal (IN) route, they enter the nasal cavity and go to the brain via connections between the olfactory and trigeminal nerves and the nasal mucosa in N2B. Delivering phytochemical, bioactive and synthetic NF is being investigated with the N2B delivery strategy. The mucociliary clearance, enzyme degradation, and drug translocations by efflux mechanisms are significant issues associated with N2B delivery. This review article discusses the types of neuropsychiatric disorders and their treatment with plant-derived as well as synthetic drug-loaded NFs administered via the IN-delivery system. In conclusion, this review provided a comprehensive and critical overview of the IN applicability of plant-derived NFs for psychiatric disorders.

Epigenetic aging in major depressive disorder: Clocks, mechanisms and therapeutic perspectives

Depression, a chronic mental disorder characterized by persistent sadness, loss of interest, and difficulty in daily tasks, impacts millions globally with varying treatment options. Antidepressants, despite their long half-life and minimal effectiveness, leave half of patients undertreated, highlighting the need for new therapies to enhance well-being. Epigenetics, which studies genetic changes in gene expression or cellular phenotype without altering the underlying Deoxyribonucleic Acid (DNA) sequence, is explored in this article. This article delves into the intricate relationship between epigenetic mechanisms and depression, shedding light on how environmental stressors, early-life adversity, and genetic predispositions shape gene expression patterns associated with depression. We have also discussed Histone Deacetylase (HDAC) inhibitors, which enhance cognitive function and mood regulation in depression. Non-coding RNAs, (ncRNAs) such as Long Non-Coding RNAs (lncRNAs) and micro RNA (miRNAs), are highlighted as potential biomarkers for detecting and monitoring major depressive disorder (MDD). This article also emphasizes the reversible nature of epigenetic modifications and their influence on neuronal growth processes, underscoring the dynamic interplay between genetics, environment, and epigenetics in depression development. It explores the therapeutic potential of targeting epigenetic pathways in treating clinical depression. Additionally, it examines clinical findings related to epigenetic clocks and their role in studying depression and biological aging.

Factors Associated with the Development of Depression and the Influence of Obesity on Depressive Disorders: A Narrative Review

Depression affects several aspects of life, including socioeconomic status, relationships, behavior, emotions, and overall health. The etiology of depression is complex and influenced by various factors, with obesity emerging as a significant contributor. This narrative review aims to investigate the factors associated with the development of depression, with a particular focus on the role of obesity. The literature search was conducted on PubMed, Embase, and PsycINFO from May to July 2024. The review highlights the impact of environmental and socioeconomic conditions; lifestyle choices, including physical activity and dietary habits; stress; traumatic experiences; neurotransmitter imbalances; medical and psychological conditions; hormone fluctuations; and epigenetic factors on depression. A key emphasis is placed on the inflammatory processes linked to obesity, which may drive the bidirectional relationship between obesity and depression. The findings suggest that obesity is associated with an increased risk of depression, potentially due to chronic inflammation, neurochemical dysregulation, and the emotional and social challenges related to weight stigma and obesity management. Understanding these interconnected factors is important for developing targeted interventions to address both obesity and depression, leading to improved quality of life for those affected.

Deciphering Depression: Epigenetic Mechanisms and Treatment Strategies

Depression, a significant mental health disorder, is under intense research scrutiny to uncover its molecular foundations. Epigenetics, which focuses on controlling gene expression without altering DNA sequences, offers promising avenues for innovative treatment. This review explores the pivotal role of epigenetics in depression, emphasizing two key aspects: (I) identifying epigenetic targets for new antidepressants and (II) using personalized medicine based on distinct epigenetic profiles, highlighting potential epigenetic focal points such as DNA methylation, histone structure alterations, and non-coding RNA molecules such as miRNAs. Variations in DNA methylation in individuals with depression provide opportunities to target genes that are associated with neuroplasticity and synaptic activity. Aberrant histone acetylation may indicate that antidepressant strategies involve enzyme modifications. Modulating miRNA levels can reshape depression-linked gene expression. The second section discusses personalized medicine based on epigenetic profiles. Analyzing these patterns could identify biomarkers associated with treatment response and susceptibility to depression, facilitating tailored treatments and proactive mental health care. Addressing ethical concerns regarding epigenetic information, such as privacy and stigmatization, is crucial in understanding the biological basis of depression. Therefore, researchers must consider these issues when examining the role of epigenetics in mental health disorders. The importance of epigenetics in depression is a critical aspect of modern medical research. These findings hold great potential for novel antidepressant medications and personalized treatments, which would significantly improve patient outcomes, and transform psychiatry. As research progresses, it is expected to uncover more complex aspects of epigenetic processes associated with depression, enhance our comprehension, and increase the effectiveness of therapies.

Histone 3 Trimethylation Patterns are Associated with Resilience or Stress Susceptibility in a Rat Model of Major Depression Disorder

Major Depressive Disorder (MDD) is a severe and multifactorial psychiatric condition. Evidence has shown that environmental factors, such as stress, significantly explain MDD pathophysiology. Studies have hypothesized that changes in histone methylation patterns are involved in impaired glutamatergic signaling. Based on this scenario, this study aims to investigate histone 3 involvement in depression susceptibility or resilience in MDD pathophysiology by investigating cellular and molecular parameters related to i) glutamatergic neurotransmission, ii) astrocytic functioning, and iii) neurogenesis. For this, we subjected male Wistar rats to the Chronic Unpredictable Mild Stress (CUMS) model of depression. We propose that by evaluating the sucrose consumption, open field, and object recognition test performance from animals submitted to CUMS, it is possible to predict with high specificity rats with susceptibility to depressive-like phenotype and resilient to the depressive-like phenotype. We also demonstrated, for the first time, that patterns of H3K4me3, H3K9me3, H3K27me3, and H3K36me3 trimethylation are strictly associated with the resilient or susceptible to depressive-like phenotype in a brain-region-specific manner. Additionally, susceptible animals have reduced DCx and GFAP and resilient animals present increase of AQP-4 immunoreactivity. Together, these results provide evidence that H3 trimethylations are related to the development of the resilient or susceptible to depressive-like phenotype, contributing to further advances in the pathophysiology of MDD and the discovery of mechanisms behind resilience.

Decoding depression: a comprehensive multi-cohort exploration of blood DNA methylation using machine learning and deep learning approaches

The causes of depression are complex, and the current diagnosis methods rely solely on psychiatric evaluations with no incorporation of laboratory biomarkers in clinical practices. We investigated the stability of blood DNA methylation depression signatures in six different populations using six public and two domestic cohorts (n = 1942) conducting mega-analysis and meta-analysis of the individual studies. We evaluated 12 machine learning and deep learning strategies for depression classification both in cross-validation (CV) and in hold-out tests using merged data from 8 separate batches, constructing models with both biased and unbiased feature selection. We found 1987 CpG sites related to depression in both mega- and meta-analysis at the nominal level, and the associated genes were nominally related to axon guidance and immune pathways based on enrichment analysis and eQTM data. Random forest classifiers achieved the highest performance (AUC 0.73 and 0.76) in CV and hold-out tests respectively on the batch-level processed data. In contrast, the methylation showed low predictive power (all AUCs < 0.57) for all classifiers in CV and no predictive power in hold-out tests when used with harmonized data. All models achieved significantly better performance (>14% gain in AUCs) with pre-selected features (selection bias), with some of the models (joint autoencoder-classifier) reaching AUCs of up to 0.91 in the final testing regardless of data preparation. Different algorithmic feature selection approaches may outperform limma, however, random forest models perform well regardless of the strategy. The results provide an overview over potential future biomarkers for depression and highlight many important methodological aspects for DNA methylation-based depression profiling including the use of machine learning strategies.

Epigenome-Wide Association Study of Depressive Symptoms in Black Women in the InterGEN Study

(1) The prevalence of depression is two times higher in women than men. Black women have an increased risk of depression due to stressors such as low socioeconomic status and perceived discrimination. Depression is likely influenced by both genetic and environmental factors. Psychosocial stressors can influence DNA methylation (DNAm), leading to changes in gene expression and ultimately, depression. The objective of this study was to examine associations between DNAm and depressive symptoms in Black women. (2) This study was a secondary analysis of data from the Intergenerational Impact of Genetic and Psychological Factors on Blood Pressure (InterGEN) Study. Perceived discrimination was assessed using Krieger's Experiences of Discrimination and Waelde's Race-Related Events Scale, and participants were screened for depressive symptoms with the Beck Depression Inventory. Raw data from saliva samples were analyzed using the Illumina Infinium Epic (850 K) BeadChip and then preprocessed in RStudio. (3) Differential methylation analysis identified DNAm sites and regions associated with depressive symptoms. Six DNAm sites had a q-value less than 0.05. Additionally, of the 25 regions identified, 12 were associated with neurological diseases or disorders. (4) These findings suggest that there is a neurological component to depression, which should be considered during treatment.

Neuroimaging and epigenetic analysis reveal novel epigenetic loci in major depressive disorder

BACKGROUND

Epigenetic modifications, such as DNA methylation, contribute to the pathophysiology of major depressive disorder (MDD). This study aimed to identify novel MDD-associated epigenetic loci using DNA methylation profiles and explore the correlations between epigenetic loci and cortical thickness changes in patients with MDD.

METHODS

A total of 350 patients with MDD and 161 healthy controls (HCs) were included in the epigenome-wide association studies (EWAS). We analyzed methylation, copy number alteration (CNA), and gene network profiles in the MDD group. A total of 234 patients with MDD and 135 HCs were included in neuroimaging methylation analysis. Pearson's partial correlation analysis was used to estimate the correlation between cortical thickness of brain regions and DNA methylation levels of the loci.

RESULTS

In total, 2018 differentially methylated probes (DMPs) and 351 differentially methylated regions (DMRs) were identified. DMP-related genes were enriched in two networks involved in the central nervous system. In neuroimaging analysis, patients with MDD showed cortical thinning in the prefrontal regions and cortical thickening in several occipital regions. Cortical thickness of the left ventrolateral prefrontal cortex (VLPFC, i.e. pars triangularis) was negatively correlated with eight DMPs associated with six genes (EML6, ZFP64, CLSTN3, KCNMA1, TAOK2, and NT5E).

CONCLUSION

Through combining DNA methylation and neuroimaging analyses, negative correlations were identified between the cortical thickness of the left VLPFC and DNA methylation levels of eight DMPs. Our findings could improve our understanding of the pathophysiology of MDD.

Characterization of rice endosperm-derived antidepressant-like peptide (REAP): An orally active novel tridecapeptide derived from rice protein

It is ideal to ingest bioactive substances from daily foods to stay healthy. Rice is the staple food for almost half of the human population. We found that an orally administered enzymatic digest of rice endosperm protein exhibits antidepressant-like effects in the tail suspension test (TST) using mice. A comprehensive peptide analysis of the digest using liquid chromatography-tandem mass spectrometry was performed, and a tridecapeptide QQFLPEGQSQSQK, detected in the digest, was chemosynthesized. Oral administration of the tridecapeptide exhibited antidepressant-like effects at a low dose comparable to classical antidepressant in the TST. This also exhibited anti-depressant-like effect in the forced swim test. We named it rice endosperm-derived antidepressant-like peptide (REAP). Intriguingly, intraperitoneal administration had no effect. Orally administered REAP(8-13) but not REAP(1-7) exhibited antidepressant-like activity, suggesting that the C-terminal structure is important for the antidepressant-like effect. We confirmed the presence of REAP, corresponding to rice glutelin type B4(130-142) and B5(130-142), in the digest. The effects of REAP were blocked by both dopamine D1 and D2 antagonists. These results suggest that it exerts its antidepressant-like activity through activation of the dopamine system. Taken together, oral administration of a novel tridecapeptide exhibited antidepressant-like effects via the dopamine system. This is the first report of a rice-derived peptide that exhibits antidepressant-like effects.

Discovering the Potential Value of Coenzyme Q10 as an Adjuvant Treatment in Patients With Depression

PURPOSE/BACKGROUND

Depressive disorder or mental cold is the most common mental disorder, and depression exists all over the world and in all countries and cultures. The results of several studies have shown that using compounds with antioxidant properties has been fruitful in patients with depression. Coenzyme Q10 (CoQ10) is a fat-soluble antioxidant and exerts its antioxidant effect by directly neutralizing free radicals or reducing tocopherol and preventing the inhibition of mitochondrial activity because of oxidative stress. This study aimed to investigate the effects of oral CoQ10 in patients with depression as an adjunctive treatment.

METHODS/PROCEDURES

Sixty-nine patients with moderate and severe depression were randomly divided into 2 CoQ10 groups (36) and placebo (33). The first group of patients received CoQ10 supplements at a dose of 200 mg daily for 8 weeks along with standard interventions and treatments for depression, and the second group received standard treatments for depression along with a placebo. The change in the score of Montgomery-Åsberg Depression Rating Scale depression scale was evaluated 4 and 8 weeks after the intervention. Also, at baseline and 8 weeks later at the end of the study, serum levels of total antioxidant capacity, total thiol groups, nitric oxide, malondialdehyde, and interleukin 6 were assessed.

FINDINGS/RESULTS

The changes in the depression score at the end of the study showed that, in the group receiving the CoQ10 supplement after 8 weeks, there was a reduction in depression symptoms, which was statistically significant compared with before the start of the study Meanwhile, no significant changes were observed in the patients of the placebo group in terms of symptom reduction. Compared with baseline and the placebo condition, serum levels of nitric oxide and total thiol groups significantly decreased and increased, respectively. Also, no statistically significant changes were observed for interleukin 6, malondialdehyde, and total antioxidant capacity.

IMPLICATIONS/CONCLUSIONS

A dose of 200 mg of CoQ10 supplement daily for 8 weeks can reduce depression and fatigue, as well as improve the quality of life of patients with depression. In addition, CoQ10 can significantly improve inflammation and oxidative stress status in patients with depression.

Global, regional, and national incidence trends of depressive disorder, 1990-2019: An age-period-cohort analysis based on the Global Burden of Disease 2019 study

BACKGROUND

Depressive disorder is a severe global public health problem. It is crucial to evaluate the global incidence trends of depressive disorder.

METHODS

The incidence data were drawn from the Global Burden of Disease Study (GBD) 2019. Estimates were presented by global and sociodemographic index (SDI) quintiles, and the age-period-cohort (APC) model was used to estimate the incidence trends.

RESULTS

APC analysis indicated a decline in depressive disorder incidence globally (net drift = -0.24%, 95%CI: -0.29, -0.18), except for an increase in SDI regions (net drift = 0.07, 95%CI:0, 0.14). In high SDI regions, depressive disorder incidence increased among the younger and declined among the elder population, whereas the opposite trend was observed in middle and low-middle SDI regions. The depressive disorder incidence increased significantly among people aged 15 to 24 years after adjusting for age effects, decreased since 2000 after adjusting for period effects and increased rapidly in the birth cohort after 1990 in high SDI by adjusting for cohort effects.

CONCLUSION

Globally, there was a declining trend of depressive disorder incidence in 1990-2019. Specifically, the incidence was declining globally in younger populations, while increasing in older populations. However, this trend differed depending on the SDI of the region.

Hypothalamic Gene Expression in a Rat Model of Chronic Unpredictable Mild Stress Treated with Electroacupuncture

Depression is characterized by the loss of pleasure and a depressed mood, and it is a common mental disorder in the twenty-first century. Multiple gene imbalances, which are considered pathological factors in depression, were detected in the brain. Electroacupuncture is an effective therapeutic approach for depression that has minimal side effects. As a crucial structure in the hypothalamus-pituitary-adrenal, the hypothalamus plays a key role in depression. Our study focused on the transcriptome level in the hypothalamus of depressive rats. After chronic unpredictable mild stress, the rats exhibited depressive-like behaviors, such as decreased sucrose consumption in the SPT, increased time in the central area of the OFT and increased immobility in the FST. Moreover, electroacupuncture alleviated depressive behaviors. Because of the importance of the hypothalamus in depression, we next detected gene expression in the hypothalamus. A total of 510 genes (125 upregulated genes and 385 downregulated genes) were detected in the hypothalamus of depressive rats. 15 of the 125 upregulated genes and 63 of the 385 downregulated genes could be altered by electroacupuncture, which suggests the antidepressant effect of electroacupuncture. Our study also provided the evidence that regulation of transcriptome in the hypothalamus might be a potential mechanism of electroacupuncture treatment.

Group differences in OXT methylation between patients with Major Depressive Disorder and healthy controls: A pre-registered replication study

Depression is linked to stress which leaves traces in the epigenetic signature of genes. The oxytocin system is implicated in allostatic processes promoting adaption to environmental stressors. Interactions of the oxytocin system with the environment, e.g., methylation of the gene coding for oxytocin (OXT), are candidates for the investigation of the biological underpinnings of depression. Recently, we found hypomethylation of OXT in patients with Major Depressive Disorder (MDD) compared to healthy controls (HC). Since the replicability of findings is a key point of criticism in (epi‑)genetic research, we aimed to confirm our previous findings in a pre-registered study (data was stored in a database prior to pre-registration) within a new sample of n = 85 patients with MDD and n = 85 HC. We investigated OXT DNA-methylation in peripheral blood samples, stressful life events and depression severity. In accordance with our previous study, we found hypomethylation of OXT in patients with MDD compared to HC. Methylation was not associated with stressful life events. Patients reported significantly more stressful life events compared to HC. Our study revealed that hypomethylation of OXT can be demonstrated in a reproducible fashion and provides further evidence for the involvement of the oxytocin system in depression.

Epigenetics, Nutrition, and the Brain: Improving Mental Health through Diet

The relationship between nutrition and brain health is intricate. Studies suggest that nutrients during early life impact not only human physiology but also mental health. Although the exact molecular mechanisms that depict this relationship remain unclear, there are indications that environmental factors such as eating, lifestyle habits, stress, and physical activity, influence our genes and modulate their function by epigenetic mechanisms to shape mental health outcomes. Epigenetic mechanisms act as crucial link between genes and environmental influences, proving that non-genetic factors could have enduring effects on the epigenome and influence health trajectories. We review studies that demonstrated an epigenetic mechanism of action of nutrition on mental health, focusing on the role of specific micronutrients during critical stages of brain development. The methyl-donor micronutrients of the one-carbon metabolism, such as choline, betaine, methionine, folic acid, VitB6 and VitB12 play critical roles in various physiological processes, including DNA and histone methylation. These micronutrients have been shown to alter gene function and susceptibility to diseases including mental health and metabolic disorders. Understanding how micronutrients influence metabolic genes in humans can lead to the implementation of early nutritional interventions to reduce the risk of developing metabolic and mental health disorders later in life.

The role of ncRNAs in depression

Depressive disorders have a significant impact on public health, and depression have an unsatisfactory recurrence rate and are challenging to treat. Non-coding RNAs (ncRNAs) are RNAs that do not code protein, which have been shown to be crucial for transcriptional regulation. NcRNAs are important to the onset, progress and treatment of depression because they regulate various physiological functions. This makes them distinctively useful as biomarkers for diagnosing and tracking responses to therapy among individuals with depression. It is important to seek out and summarize the research findings on the impact of ncRNAs on depression since significant advancements have been made in this area recently. Hence, we methodically outlined the findings of published researches on ncRNAs and depression, focusing on microRNAs. Above all, this review aims to improve our understanding of ncRNAs and provide new insights of the diagnosis and treatment of depression.

Genetics, epigenetics, and neurobiology of childhood-onset depression: an umbrella review

Depression is a serious and persistent psychiatric disorder that commonly first manifests during childhood. Depression that starts in childhood is increasing in frequency, likely due both to evolutionary trends and to increased recognition of the disorder. In this umbrella review, we systematically searched the extant literature for genetic, epigenetic, and neurobiological factors that contribute to a childhood onset of depression. We searched PubMed, EMBASE, OVID/PsychInfo, and Google Scholar with the following inclusion criteria: (1) systematic review or meta-analysis from a peer-reviewed journal; (2) inclusion of a measure assessing early age of onset of depression; and (3) assessment of neurobiological, genetic, environmental, and epigenetic predictors of early onset depression. Findings from 89 systematic reviews of moderate to high quality suggest that childhood-onset depressive disorders have neurobiological, genetic, environmental, and epigenetic roots consistent with a diathesis-stress theory of depression. This review identified key putative markers that may be targeted for personalized clinical decision-making and provide important insights concerning candidate mechanisms that might underpin the early onset of depression.

Functional AGXT2 SNP rs180749 variant and depressive symptoms: Baseline data from the Aidai Cohort Study in Japan

No study has shown the relationship between alanine-glyoxylate aminotransferase 2 (AGXT2) single nucleotide polymorphisms (SNPs) and depressive symptoms. The present case-control study examined this relationship in Japanese adults. Cases and control participants were selected from those who participated in the baseline survey of the Aidai Cohort Study, which is an ongoing cohort study. Cases comprised 280 participants with depressive symptoms based on a Center for Epidemiologic Studies Depression Scale (CES-D) score ≥ 16. Control participants comprised 2034 participants without depressive symptoms based on the CES-D who had not been diagnosed by a physician as having depression or who had not been currently taking medication for depression. Adjustment was made for age, sex, smoking status, alcohol consumption, leisure time physical activity, education, body mass index, hypertension, dyslipidemia, and diabetes mellitus. Compared with the GG genotype of rs180749, both the GA and AA genotypes were significantly positively associated with the risk of depressive symptoms assessed by the CES-D: the adjusted odds ratios for the GA and AA genotypes were 2.83 (95% confidence interval [CI] 1.23-8.24) and 3.10 (95% CI 1.37-8.92), respectively. The TGC haplotype of rs37370, rs180749, and rs16899974 was significantly inversely related to depressive symptoms (crude OR 0.67; 95% CI 0.49-0.90), whereas the TAC haplotype was significantly positively associated with depressive symptoms (crude OR 1.24; 95% CI 1.01-1.52). This is the first study to show significant associations between AGXT2 SNP rs180749, the TGC haplotype, and the TAC haplotype and depressive symptoms.

MicroRNAs as Diagnostic Biomarkers and Predictors of Antidepressant Response in Major Depressive Disorder: A Systematic Review

Despite the hardships of major depressive disorder (MDD), biomarkers for the diagnosis and pharmacological management of this condition are lacking. MicroRNAs are epigenetic mechanisms that could provide promising MDD biomarkers. Our aim was to summarize the findings and provide validation for the selection and use of specific microRNAs as biomarkers in the diagnosis and treatment of MDD. A systematic review was conducted using the PubMed/Medline, Cochrane, PsycINFO, Embase, and LILACS databases from March 2022 to November 2023, with clusters of terms based on "microRNA" and "antidepressant". Studies involving human subjects, animal models, and cell cultures were included, whereas those that evaluated herbal medicines, non-pharmacological therapies, or epigenetic mechanisms other than miRNA were excluded. The review revealed differences in the expression of various microRNAs when considering the time of assessment (before or after antidepressant treatment) and the population studied. However, due to the heterogeneity of the microRNAs investigated, the limited size of the samples, and the wide variety of antidepressants used, few conclusions could be made. Despite the observed heterogeneity, the following microRNAs were determined to be important factors in MDD and the antidepressant response: mir-1202, mir-135, mir-124, and mir-16. The findings indicate the potential for the use of microRNAs as biomarkers for the diagnosis and treatment of MDD; however, more homogeneous studies are needed.

Integrating mitoepigenetics into research in mood disorders: a state-of-the-art review

Mood disorders, including major depressive disorder and bipolar disorder, are highly prevalent and stand among the leading causes of disability. Despite the largely elusive nature of the molecular mechanisms underpinning these disorders, two pivotal contributors-mitochondrial dysfunctions and epigenetic alterations-have emerged as significant players in their pathogenesis. This state-of-the-art review aims to present existing data on epigenetic alterations in the mitochondrial genome in mood disorders, laying the groundwork for future research into their pathogenesis. Associations between abnormalities in mitochondrial function and mood disorders have been observed, with evidence pointing to notable changes in mitochondrial DNA (mtDNA). These changes encompass variations in copy number and oxidative damage. However, information on additional epigenetic alterations in the mitochondrial genome remains limited. Recent studies have delved into alterations in mtDNA and regulations in the mitochondrial genome, giving rise to the burgeoning field of mitochondrial epigenetics. Mitochondrial epigenetics encompasses three main categories of modifications: mtDNA methylation/hydroxymethylation, modifications of mitochondrial nucleoids, and mitochondrial RNA alterations. The epigenetic modulation of mitochondrial nucleoids, lacking histones, may impact mtDNA function. Additionally, mitochondrial RNAs, including non-coding RNAs, present a complex landscape influencing interactions between the mitochondria and the nucleus. The exploration of mitochondrial epigenetics offers valuable perspectives on how these alterations impact neurodegenerative diseases, presenting an intriguing avenue for research on mood disorders. Investigations into post-translational modifications and the role of mitochondrial non-coding RNAs hold promise to unravel the dynamics of mitoepigenetics in mood disorders, providing crucial insights for future therapeutic interventions.

Role of estrogen in treatment of female depression

Depression is a neurological disorder that profoundly affects human physical and mental health, resulting in various changes in the central nervous system. Despite several prominent hypotheses, such as the monoaminergic theory, hypothalamic-pituitary-adrenal (HPA) axis theory, neuroinflammation, and neuroplasticity, the current understanding of depression's pathogenesis remains incomplete. Importantly, depression is a gender-dimorphic disorder, with women exhibiting higher incidence rates than men. Given estrogen's pivotal role in the menstrual cycle, it is reasonable to postulate that its fluctuating levels could contribute to the pathogenesis of depression. Estrogen acts by binding to a diversity of receptors, which are widely distributed in the central nervous system. An abundance of research has established that estrogen and its receptors play a crucial role in depression, spanning pathogenesis and treatment. In this comprehensive review, we provide an in-depth analysis of the fundamental role of estrogen and its receptors in depression, with a focus on neuroinflammation, neuroendocrinology, and neuroplasticity. Furthermore, we discuss potential mechanisms underlying the therapeutic effects of estrogen in the treatment of depression, which may pave the way for new antidepressant drug development and alternative treatment options.

Epigenetic processes associated with neonatal spinal transection

In early development, the spinal cord in healthy or disease states displays remarkable activity-dependent changes in plasticity, which may be in part due to the increased activity of brain derived neurotrophic factor (BDNF). Indeed, BDNF delivery has been efficacious in partially ameliorating many of the neurobiological and behavioral consequences of spinal cord injury (SCI), making elucidating the role of BDNF in the normative developing and injured spinal cord a critical research focus. Recent work in our laboratory provided evidence for aberrant global and locus-specific epigenetic changes in methylation of the Bdnf gene as a consequence of SCI. In the present study, animals underwent thoracic lesions on P1, with cervical and lumbar tissue being later collected on P7, P14, and P21. Levels of Bdnf expression and methylation (exon IX and exon IV), in addition to global methylation levels were quantified at each timepoint. Results indicated locus-specific reductions of Bdnf expression that was accompanied by a parallel increase in methylation caudal to the injury site, with animals displaying increased Bdnf expression at the P14 timepoint. Together, these findings suggest that epigenetic activity of the Bdnf gene may act as biomarker in the etiology and intervention effort efficacy following SCI.