Search

Most previous studies in the pathophysiology of major depressive disorder (MDD) focused on fecal samples, which limit the identification of the gut mucosal and luminal microbiome in depression. Here, we address this knowledge gap. Male cynomolgus macaques (Macaca fascicularis) were randomly assigned to a chronic unpredictable mild stress (CUMS) group, or to an unstressed control group. Behavioral tests were completed in both groups. At endpoint, microbe composition of paired mucosal and luminal samples from cecum, ascending, transverse, and descending colons were determined by 16S ribosomal RNA gene sequencing. The levels of 34 metabolites involved in carbohydrate or energy metabolism in luminal samples were measured by targeted metabolomics profiling. CUMS macaques demonstrated significantly more depressive-like behaviors than controls. We found differences in mucosal and luminal microbial composition between the two groups, which were characterized by Firmicutes and Bacteriodetes at the phylum level, as well as Prevotellaceae and Lachnospiraceae at the family level. The majority of discriminative microbes correlated with the depressive-like behavioral phenotype. In addition, we found 27 significantly different microbiome community functions between the two groups in mucosa, and one in lumen, which were mainly involved in carbohydrate and energy metabolism. A total of nine metabolites involved in these pathways were depleted in CUMS animals. Together, CUMS macaques with depressive-like behaviors associated with distinct alterations of covarying microbiota, carbohydrate and energy metabolism in mucosa and lumen. Further studies should focus on the mucosal and luminal microbiome to provide a deeper spatiotemporal perspective of microbial alterations in the pathogenesis of MDD.

BackgroundAvailable evidence on the comparative efficacy and acceptability of psychotherapies for post-traumatic stress disorder (PTSD) in children and adolescents remains uncertain.ObjectiveWe aimed to compare and rank the different types and formats of psychotherapies for PTSD in children and adolescents.MethodsWe searched eight databases and other international registers up to 31 December 2020. The pairwise meta-analyses and frequentist network meta-analyses estimated pooled standardised mean differences (SMDs) and ORs with random-effects model. Efficacy at post-treatment and follow-up, acceptability, depressive and anxiety symptoms were measured.FindingsWe included 56 randomised controlled trials with 5327 patients comparing 14 different types of psychotherapies and 3 control conditions. For efficacy, cognitive processing therapy (CPT), behavioural therapy (BT), individual trauma-focused cognitive–behavioural therapy (TF-CBT), eye movement desensitisation and reprocessing, and group TF-CBT were significantly superior to all control conditions at post-treatment and follow-up (SMDs between −2.42 and −0.25). Moreover, CPT, BT and individual TF-CBT were more effective than supportive therapy (SMDs between −1.92 and −0.49). Results for depressive and anxiety symptoms were similar to the findings for the primary outcome. Most of the results were rated as ‘moderate’ to ‘very low’ in terms of confidence of evidence.ConclusionsCPT, BT and individual TF-CBT appear to be the best choices of psychotherapy for PTSD in young patients. Other types and different ways of delivering psychological treatment can be alternative options. Clinicians should consider the importance of each outcome and the patients’ preferences in real clinical practice.

Childhood trauma is a leading risk factor for adolescents developing major depressive disorder (MDD); however, the underlying neuroimaging mechanisms remain unclear. This study aimed to investigate the association among childhood trauma, MDD and brain dysfunctions by combining static and dynamic brain network models. We recruited 46 first-episode drug-naïve adolescent MDD patients with childhood trauma (MDD-CT), 53 MDD patients without childhood trauma (MDD-nCT), and 90 healthy controls (HCs) for resting-state functional magnetic resonance imaging (fMRI) scans; all participants were aged 13–18 years. Compared to the HCs and MDD-nCT groups, the MDD-CT group exhibited significantly higher global and local efficiency in static brain networks and significantly higher temporal correlation coefficients in dynamic brain network models at the whole-brain level, and altered the local efficiency of default mode network (DMN) and temporal correlation coefficients of DMN, salience (SAN), and attention (ATN) networks at the local perspective. Correlation analysis indicated that altered brain network features and clinical symptoms, childhood trauma, and particularly emotional neglect were highly correlated in adolescents with MDD. This study may provide new evidence for the dysconnectivity hypothesis regarding the associations between childhood trauma and MDD in adolescents from the perspectives of both static and dynamic brain topology.