A comparison of symptoms of bipolar and unipolar depression in postpartum women

Understanding and treating postpartum depression: a narrative review

Postpartum depression (PPD) is an increasingly prevalent but still poorly characterized disorder. Causal and modulating factors include hormones fluctuations, such as estrogen, progesterone, and allopregnolone, pathways imbalances, such as oxytocin and kynurenine, chronobiological factors, and brain imaging alterations. Treatment may differ from the traditional major depression management, while selective serotonin reuptake inhibitors such as sertraline are commonly used and suggested by guidelines, neurosteroids such as brexanolone and the more convenient zuranolone have been recently approved. Newer neurosteroids such as ganaxolone, valaxanolone, and lysaxanolone are currently under development, but also esketamine and psychedelics are promising potential treatments. Other somatic treatments including brain stimulation techniques and light therapy also showed benefit. PPD is therefore increasingly understood as, at least partially, independent from major depressive disorder. Specific and individualized treatments including pharmacological and non-pharmacological therapies are progressively being introduced in the routine clinical practice.

Mendelian randomization analyses for the causal relationship between early age at first sexual intercourse, early age at first live birth, and postpartum depression in pregnant women

Introduction

There are insufficient epidemiological studies on the impact of age at first sexual intercourse (AFS) and age at first live birth (AFB) on postpartum depression (PPD) in pregnant women, and the conclusions of these studies are inconsistent.

Methods

We performed a Mendelian randomization (MR) study to determine the causal relationship between AFS or AFB and the risk of PPD. The summary data were extracted from genome-wide association study (GWAS) summary datasets. We selected the instrumental variables according to the P value of exposure-related single nucleotide polymorphisms (P<5 ×10-9 for AFS and P<5 ×10-8 for AFB) and estimated the linkage disequilibrium using the clump parameter (10,000 kb, r2 < 0.001). Single nucleotide polymorphisms were considered instrumental variables that were significantly associated with exposure factors without linkage disequilibrium. The F-statistics of the instrumental variables should all be larger than 10. A random-effects model of IVW was constructed as the main method in our study.

Results and discussion

MR studies based on GWAS data revealed that both AFS (OR = 0.4, P <0.001) and AFB (OR = 0.38, P <0.001) were negatively correlated with the risk of PPD. Early AFS and early AFB should be studied as possible risk factors for PPD in the future. Public health departments should attach importance to sex education for young girls. The results of our TSMR should be verified by high-quality prospective epidemiological studies in the future.

miR-204-5p Plays a Critical Role in the Pathogenesis of Depression and Anti-depression Action of Venlafaxine in the Hippocampus of Mice

BACKGROUND

Venlafaxine has been demonstrated to treat diseases such as social anxiety disorder and depression. Most of antidepressants including venlafaxine have a certain effect, but significant side effects. Therefore, it is necessary for us to research the development of novel antidepressants for effective treatment in practice. MicroRNA-204 (miR-204) is highly expressed in brain tissue, and plays a critical role in the synaptic plasticity of hippocampal neurons in rats. However, the underlying molecular mechanism of miR-204 remains unclear to date, this study aims to offer unique insights into depression and provide a theoretical basis for clinical physicians.

METHODS

A chronic social defeat stress (CSDS) was initially adopted for establishing a mice model of depression in this research and depression-like behaviors were evaluated by a series of behavioral experiments including the sucrose preference test (SPT), the tail suspension test (TST), the forced swim test (FST) and the social interaction test (SIT). Quantitative real-time reverse transcription PCR (qRT-PCR) was also conducted to test the expression levels of miR-204 and BDNF in the hippocampus of mice. Finally, gene interference of miR-204-5p was further adopted to test whether miR-204-5p played an effective role in the antidepressant effects of venlafaxine in mice.

RESULTS

Our data implicated that CSDS significantly increased the miR-204-5p but not miR-204-3p levels in the hippocampus of mice. The treatment of venlafaxine obviously relieved depression- like behaviors of CSDS-induced mice. The usage of venlafaxine abolished the increasing effects on the expression of miR-204-5p but up-regulated the BDNF expression level in CSDS-exposured mice. More importantly, we found that genetic overexpression of miR-204-5p decreased the reverse effects of venlafaxine on depressive-like behaviors and genetic knockdown of hippocampal miR-204-5p relieved the depressive-like behaviors and neurogenesis in CSDS-induced mice.

CONCLUSION

miR-204-5p played an effective role in the antidepressant effects of venlafaxine in CSDS-induced mice.

Hot spots and frontiers of postpartum depression research in the past 5 years: A bibliometric analysis

Objective

This study applied the bibliometric method to analyze the hotspots and frontiers in the field of postpartum depression research from 2017 to 2021.

Methods

A computer-based search for studies related to postpartum depression (PPD) was conducted in the Web of Science Core Collection from 2017 to 2021. Using CiteSpace 5.8. R3 visualization software, this paper analyzed the hot spots and frontiers of postpartum depression research from countries, institutions, authors, cited references and keywords, and drew corresponding knowledge maps.

Results

A total of 3,789 articles were retrieved, and the annual publication volume showed a steady increase. The countries and institutions with the most publications were the United States and the University of Toronto, respectively. Cindylee Dennis was the most productive author. The most frequently cited and centrally cited articles were meta-analyses on risk factors associated with antenatal depression or anxiety and meta-analyses on the prevalence of antenatal or postnatal anxiety, respectively. The research hotspots in the field of postpartum depression in the past 5 years mainly focused on the risk factors for PPD, and the impact of the COVID-19 epidemic on PPD. Providing various aspects of social and family support to women with PPD may be a research trend in this field.

Conclusion

This study provides a trend and frontier in the field of postpartum depression, and valuable information for researchers to find potential partners and partner countries, and a reference for future research topics and development directions.

Hippocampal miR-124 Participates in the Pathogenesis of Depression via Regulating the Expression of BDNF in a Chronic Social Defeat Stress Model of Depression

OBJECTIVE

As one of the most prevalent psychiatric disorders, the exact pathogenesis of depression remains elusive. Therefore, there is an urgent need to identify novel antidepressants for effective treatment. MicroRNA-124 (miR-124), the most abundant miRNA in brain tissue, plays a key effect on adult neurogenesis and neuronal differentiation. However, the mechanism of miR-124 in depression has not been clarified so far. The aim of this study is to provide broad insight into the mechanisms underlying depression.

METHODS

In the study, we used the forced swim test (FST), the tail suspension test (TST), and a Chronic Social Defeat Stress (CSDS) mice model of depression. Quantitative real-time reverse transcription PCR (qRT-PCR), western blotting, immunofluorescence and virus-mediated gene transfer were used together. The level of plasma corticosterone in mice was analyzed by Enzyme Linked Immunosorbent Assay (ELISA).

RESULTS

It was found that CSDS robustly increased the level of miR-124 in the hippocampus. Genetic knockdown of hippocampal miR-124 produced significant antidepressant-like effects in the CSDS model of depression. Furthermore, AAV-siR-124-EGFP treatment increased the level of plasma corticosterone in CSDS-induced mice. Moreover, it was found that the antidepressant-like effects induced by miR-124 inhibition required the hippocampal BDNF-TrkB system.

CONCLUSION

Hippocampal miR-124 participated in the pathogenesis of depression by regulating BDNF biosynthesis and was a feasible antidepressant target.