The interaction between estradiol change and the serotonin transporter gene (5-HTTLPR) polymorphism is associated with postpartum depressive symptoms

Potential therapeutic effects of Chinese herbal medicine in postpartum depression: Mechanisms and future directions

ETHNOPHARMACOLOGICAL RELEVANCE

Postpartum depression (PPD) is a common psychiatric disorder in women after childbirth. Per data from epidemiologic studies, PPD affects about 5%-26.32% of postpartum mothers worldwide. Biological factors underlying this condition are multiple and complex and have received extensive inquiries for the roles they play in PPD. Chinese herbal medicine (CHM), which is widely used as a complementary and alternative therapy for neurological disorders, possesses multi-component, multi-target, multi-access, and low side effect therapeutic characteristics. CHM has already shown efficacy in the treatment of PPD, and a lot more research exploring the mechanisms of its potential therapeutic effects is being conducted.

AIM OF THE REVIEW

This review provides an in-depth and comprehensive overview of the underlying mechanisms of PPD, as well as samples the progress made in researching the potential role of CHM in treating the disorder.

MATERIALS AND METHODS

Literature was searched comprehensively in scholarly electronic databases, including PubMed, Web of Science, Scopus, CNKI and WanFang DATA, using the search terms "postpartum depression", "genetic", "hormone", "immune", "neuroinflammation", "inflammation", "neurotransmitter", "neurogenesis", "brain-gut axis", "traditional Chinese medicine", "Chinese herbal medicine", "herb", and an assorted combination of these terms.

RESULTS

PPD is closely associated with genetics, as well as with the hormones, immune inflammatory, and neurotransmitter systems, neurogenesis, and gut microbes, and these biological factors often interact and work together to cause PPD. For example, inflammatory factors could suppress the production of the neurotransmitter serotonin by inducing the regulation of tryptophan-kynurenine in the direction of neurotoxicity. Many CHM constituents improve anxiety- and depression-like behaviors by interfering with the above-mentioned mechanisms and have shown decent efficacy clinically against PPD. For example, Shen-Qi-Jie-Yu-Fang invigorates the neuroendocrine system by boosting the hormone levels of hypothalamic pituitary adrenal (HPA) and hypothalamic pituitary gonadal (HPG) axes, regulating the imbalance of Treg/T-helper cells (Th) 17 and Th1/Th2, and modulating neurotransmitter system to play antidepressant roles. The Shenguiren Mixture interferes with the extracellular signal-regulated kinase (ERK) pathway to enhance the number, morphology and apoptosis of neurons in the hippocampus of PPD rats. Other herbal extracts and active ingredients of CHM, such as Paeoniflorin, hypericin, timosaponin B-III and more, also manage depression by remedying the neuroendocrine system and reducing neuroinflammation.

CONCLUSIONS

The pathogenesis of PPD is complex and diverse, with the main pathogenesis not clear. Still, CHM constituents, like Shen-Qi-Jie-Yu-Fang, the Shenguiren Mixture, Paeoniflorin, hypericin and other Chinese Medicinal Formulae, active monomers and Crude extracts, treats PPD through multifaceted interventions. Therefore, developing more CHM components for the treatment of PPD is an essential step forward.

Genetic Markers Associated with Postpartum Depression: A Review

Postpartum depression (PPD) is a common illness in mothers after childbirth. PPD negatively affect the mother's quality of life and the bond with the infant, which can interfere with the infant's emotional, social, and cognitive development. PPD is caused by various biological and psychosocial factors. The aim of this review is to summarize the latest evidence of the associations between genetic polymorphisms and PPD. PubMed and Scopus were used as the literature search databases for this review. The keywords used were postpartum depression, postnatal depression, genetic, and polymorphism. Twenty-seven articles were reviewed after screening and applying the inclusion criteria. As results, the serotonin gene (5-HTTLPR) and oxytocin genes (OXTR) have the most significant associations with PPD among other genes. Further research on PPD biomarkers should be conducted to diagnose and treat PPD patients.

Risk Factors for Postpartum Depression Based on Genetic and Epigenetic Interactions

Postpartum depression (PPD) is a serious mood disorder that tends to occur after the delivery, which may bring lifelong consequences to women and their families in terms of family relationships, social relationships, and mental health. Currently, various risk factors including environmental factors and genetic factors that may induce postpartum depression have been extensively studied. In this review, we suggest that postpartum women's susceptibility to postpartum depression may be the result of the interaction between the genes associated with postpartum depression as well as the interaction between genetic and environmental factors. We reviewed the genes that have been studied in postpartum depression, including genes related to the synthesis, metabolism, and transport of monoamine neurotransmitters, key molecules of the HPA axis, and the kynurenine pathway. These studies have found more or less gene-gene and gene-environment interactions, so we will discuss these issues in more detail. However, so far, the conclusions of these risk factors, especially genetic factors, are not completely consistent in the occurrence and exacerbation of symptoms in postpartum depression, and it is not clear how these risk factors specifically participate in the pathological mechanism of the disease and play a role. We conclude that the role of genetic polymorphisms, including genetic and epigenetic processes, in the occurrence and development of postpartum depression, is complex and ambiguous. We also note that interactions between multiple candidate genes and the environment have been suggested as causes of depression, suggesting that more definitive research is needed to understand the heritability and susceptibility of PPD. Overall, our work supports the hypothesis that postpartum depression is more likely to be caused by a combination of multiple genetic and environmental factors than by a single genetic or environmental influence.

The positive effect of mother-performed infant massage on infantile eczema and maternal mental state: A randomized controlled trial

Objective

To observe the influence of MPIM on infantile eczema, quality of life, growth and maternal mental state.

Methods

This trial was a randomized controlled study. Sixty-six full-term infants with eczema were randomly divided into eczema control group (EC group, n = 33) and eczema with MPIM group (EM group, n = 33), along with healthy full-term infants in the healthy control group (HC group, n = 31). The mothers in the EC group received the instruction of routine care, while the mothers in the EM group applied massage on the infants plus receiving the same instruction of the routine care. HC group received none of any specific intervention. Data were collected in the three groups at the baseline and at the end of 2- and 5-month intervention. Before and at the end of 2-month intervention, the following indexes were investigated in infants including the growth indexes, eczema area severity index (EASI), infantile dermatitis quality of life index (IDQOL). And the scores of self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were investigated in mothers at the same timepoints. At the end of 5-month intervention, the infants' growth and relapse condition of eczema were observed.

Results

Overall, 31 cases in HC group, 31 in EC group and 32 in EM group were included for data analysis. There were no significant differences in the indexes of infantile growth among the three groups (all P >0.05). The scores of EASI and IDQOL significantly lowered (both P < 0.001) in EC group following the instruction of routine care, along with reduced maternal scores of SAS and SDS (both P < 0.05). Compared with the EC group, the EM group showed significantly lower scores of EASI and IDQOL (both P < 0.001) and lower relapse rate (P < 0.01) in infants with eczema, along with significantly lower scores of SAS and SDS in mothers (both P < 0.01). Moreover, none of obvious adverse reaction was reported following MPIM, to which most of the mothers could adhere.

Conclusion

MPIM could effectively promote the remission of infantile eczema and reduce its relapse, along with relieving maternal anxiety and depression mood.

Clinical trial registration

Identifier: ChiCTR2200066246.

Exploration for biomarkers of postpartum depression based on metabolomics: A systematic review

BACKGROUND

Postpartum depression (PPD) is the most frequent psychiatric complication during the postnatal period and its mechanisms are not fully understood. Metabolomics, can quantitatively measure metabolites in a high-throughput method, and thus uncover the underlying pathophysiology of disease.

OBJECTIVES

In this study, we reviewed metabolomics studies conducted on PPD, aiming to understand the changes of metabolites in PPD patients and analyze the potential application of metabolomics in PPD prediction and diagnosis.

METHODS

Relevant articles were searched in PubMed, Google scholar, and Web of Science databases from January 2011 to July 2022. The metabolites involved were systematically examined and compared. MetaboAnalyst online software was applied to analyze metabolic pathways.

RESULTS

A total of 14 papers were included in this study. There were several highly reported metabolites, such as kynurenine, kynurenic acid, and eicosapentaenoic acid. Dysregulation of metabolic pathways involved amino acids metabolism, fatty acids metabolism, and steroids metabolism.

LIMITATIONS

The included studies are relatively inadequate, and further work is needed.

CONCLUSIONS

This study summarized significant metabolic alterations that provided clues for the prediction, diagnosis, and pathogenesis of PPD.

The role of central serotonergic markers and estradiol changes in perinatal mental health

OBJECTIVE

Women have an increased risk for mental distress and depressive symptoms in relation to pregnancy and birth. The serotonin transporter (SERT) may be involved in the emergence of depressive symptoms postpartum and during other sex-hormone transitions. It may be associated with cerebrospinal fluid (CSF) levels of the main serotonin metabolite 5-hydroxyindolacetic acid (5-HIAA). In 100 healthy pregnant women, who were scheduled to deliver by cesarean section (C-section), we evaluated 5-HIAA and estradiol contributions to mental distress 5 weeks postpartum.

METHODS

Eighty-two women completed the study. CSF collected at C-section was analyzed for 5-HIAA, with high performance liquid chromatography. Serum estradiol concentrations were quantified by liquid chromatography tandem mass spectrometry before C-section and postpartum. Postpartum mental distress was evaluated with the Edinburgh Postnatal Depression Scale (EPDS). Associations between EPDS, 5-HIAA, and Δestradiol were evaluated in linear regression models adjusted for age, parity and SERT genotype.

RESULTS

Higher levels of postpartum mental distress symptoms were negatively associated with a large decrease in estradiol concentrations (β_ΔE2  = 0.73, p = 0.007) and, on a trend level, positively associated with high antepartum 5-HIAA levels (β_5-HIAA  = 0.002, p = 0.06).

CONCLUSION

In a cohort of healthy pregnant women, postpartum mental distress was higher in women with high antepartum 5-HIAA (trend) and lower in women with a large perinatal estradiol decrease. We speculate that high antepartum 5-HIAA is a proxy of SERT levels, that carry over to the postpartum period and convey susceptibility to mental distress. In healthy women, the postpartum return to lower estradiol concentrations may promote mental well-being.

Depressive Symptoms are Associated with low Serotonin Levels in Plasma but are not 5-HTTLPR Genotype Dependent in Older Adults

Depressive symptoms are diagnosed by physicians using scales but their pathophysiology is unclear. Low serotonin (5-HT) levels play an important role in depression, and the 5-HT transporter (5-HTT) is an important regulator of plasma serotonin levels and reuptake. Additionally, the 5-HTT gene-linked polymorphic region (5-HTTLPR) is associated with depression. The aim was to clarify the roles of plasma serotonin levels in plasma and the 5HTTPLR polymorphism in depressive symptoms in older adults. A total of 84 older adult participants were evaluated. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale of 20 items (CESD-20). The plasma serotonin levels were determined by ELISA, and the 5-HTTLPR genotype was analyzed by PCR. Depressive symptoms were present in 39.3% (N = 33) of the participants. The median plasma serotonin level was 204.34 ng/mL (SD = 93.88). A significant correlation was found between the CESD-20 scale and plasma serotonin levels (r = -.256; p = .019). Low serotonin levels were associated with the presence of depressive symptoms (p = .001). The 5-HTTLPR analysis showed that of the 84 older adults, 35.7% had the SS genotype, 10.7% had the LL genotype, and 53.6% were heterozygous. The 5-HTTLPR polymorphism was not associated with depressive symptoms (p = .587) and plasma serotonin levels (p = 0.391). Depressive symptoms correlate with low serotonin levels in plasma, but not with the 5-HTTLPR polymorphism in older Mexican adults.

Association of DRD4 exon III and 5-HTTLPR VNTR genetic polymorphisms with psychiatric symptoms in hemodialysis patients

Mental illness is prevalent among hemodialysis (HD) patients. Given that the dopaminergic and serotonergic pathways are involved in the etiology of psychiatric disease, this study evaluated the genetic association of dopamine D4 receptor (DRD4) and serotonin transporter (SLC6A4) genes with psychiatric symptom susceptibility among HD patients. Hospital Anxiety and Depression Scale (HADS) was used to assess anxiety and depressive symptoms among patients (n = 265). Genetic polymorphisms of DRD4 (48 bp VNTR) and SLC6A4 (5-HTTLPR VNTR and rs25531) were examined using a conventional polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique, as appropriate. Significant differences were observed in the distribution of 5-HTTLPR genotypes, SLC6A4 tri-allelic-phased genotype, and DRD4-Exon III VNTR genotypes/alleles between patients with anxiety symptoms versus those with normal/borderline conditions (p<0.05). Binary logistic regression analyses showed that the heterozygous 4,5 VNTR genotype of DRD4 was associated with a higher risk of anxiety symptoms after adjusting for other covariates (odds ratio = 4.25, p = 0.028). None of the studied polymorphisms was linked to depression in HD patients. Collectively, the current findings provide genetic clues to psychopathology in HD patients and suggest that the DRD4 exon III VNTR polymorphism is involved in the etiology of anxiety in this patient population.

Perinatal depression: Heterogeneity of disease and in animal models

Perinatal depression (PND) can have either an antepartum or postpartum onset. Although the greatest risk factor for PND is previous depression history,de novoPND occurs with the majority of cases occurring in the postpartum. Timing of depression can impact etiology, prognosis, and response to treatment. Thus, it is crucial to study the impact of the heterogeneity of PND for better health outcomes. In this review, we outline the differences between antepartum and postpartum depression onset of PND. We discuss maternal physiological changes that differ between pregnancy and postpartum and how these may differentially impact depression susceptibility. We highlight changes in the maternal steroid and peptide hormone levels, immune signalling, serotonergic tone, metabolic factors, brain morphology, and the gut microbiome. Finally, we argue that studying the heterogeneity of PND in clinical and preclinical models can lead to improved knowledge of disease etiopathology and treatment outcomes.

Is Postpartum Depression Different From Depression Occurring Outside of the Perinatal Period? A Review of the Evidence

Whether a major depressive episode occurring in the postpartum period (i.e., postpartum depression [PPD]) is sufficiently distinct from major depressive episodes occurring at other times (i.e., major depressive disorder) to warrant a separate diagnosis is a point of debate with substantial clinical significance. The evidence for and against diagnostic distinction for PPD is reviewed with respect to epidemiology, etiology, and treatment. Overall, evidence that PPD is distinct from major depressive disorder is mixed and is largely affected by how the postpartum period is defined. For depression occurring in the early postpartum period (variably defined, but typically with onset in the first 8 weeks), symptom severity, heritability, and epigenetic data suggest that PPD may be distinct, whereas depression occurring in the later postpartum period may be more similar to major depressive disorder occurring outside of the perinatal period. The clinical significance of this debate is considerable given that PPD, the most common complication of childbirth, is associated with immediate and enduring adverse effects on maternal and offspring morbidity and mortality. Future research investigating the distinctiveness of PPD from major depressive disorder in general should focus on the early postpartum period when the rapid decline in hormones contributes to a withdrawal state, requiring profound adjustments in central nervous system function.