Project description:Major depressive disorder is caused by gene-environment interactions and the gut microbiota plays a pivotal role in the development of depression. However, the mechanisms by which the gut microbiota modulates depression remain elusive. Herein, we detected the differentially expressed hippocampal long non-coding RNAs (lncRNAs), messenger RNAs (mRNAs) and microRNAs (miRNAs) between mice inoculated with gut microbiota from major depressive disorder patients or healthy controls, to identify the effects of gut microbiota-dysbiosis on gene regulation patterns at the transcriptome level. We also performed functional analysis to explore the microbial-regulated pathological mechanisms of depression. Two hundred mRNAs, 358 lncRNAs and 4 miRNAs were differentially expressed between the two groups. Functional analysis of these differentially expressed mRNAs indicated dysregulated inflammatory response to be the primary pathological change. Intersecting the differentially expressed mRNAs with targets of differentially expressed miRNAs identified 47 intersected mRNAs, which were mainly related to neurodevelopment. Additionally, we constructed a microbial-regulated lncRNA-miRNA-mRNA network based on RNA-RNA interactions. According to the competitive endogenous RNA hypothesis, two neurodevelopmental ceRNA sub-networks implicating in depression were identified. This study provides new understanding of the pathogenesis of depression induced by gut microbiota-dysbiosis and may act as a theoretical basis for the development of gut microbiota-based antidepressants.
2021-12-31 | GSE189159 | GEO
Project description:Gut microbiota in patients with major depressive disorder
Project description:Major depressive disorder is caused by gene-environment interactions and the gut microbiota plays a pivotal role in the development of depression. However, the mechanisms by which the gut microbiota modulates depression remain elusive. Herein, we detected the differentially expressed hippocampal long non-coding RNAs (lncRNAs), messenger RNAs (mRNAs) and microRNAs (miRNAs) between mice inoculated with gut microbiota from major depressive disorder patients or healthy controls, to identify the effects of gut microbiota-dysbiosis on gene regulation patterns at the transcriptome level. We also performed functional analysis to explore the microbial-regulated pathological mechanisms of depression. Two hundred mRNAs, 358 lncRNAs and 4 miRNAs were differentially expressed between the two groups. Functional analysis of these differentially expressed mRNAs indicated dysregulated inflammatory response to be the primary pathological change. Intersecting the differentially expressed mRNAs with targets of differentially expressed miRNAs identified 47 intersected mRNAs, which were mainly related to neurodevelopment. Additionally, we constructed a microbial-regulated lncRNA-miRNA-mRNA network based on RNA-RNA interactions. According to the competitive endogenous RNA hypothesis, two neurodevelopmental ceRNA sub-networks implicating in depression were identified. This study provides new understanding of the pathogenesis of depression induced by gut microbiota-dysbiosis and may act as a theoretical basis for the development of gut microbiota-based antidepressants.
Project description:Genome-wide MeDIP-Sequencing was carried out on a total of 50 monozygotic twin pairs from the UK and Australia that are discordant for depression. We show that major depressive disorder is associated with significant hypermethylation within the coding region of ZBTB20, and is replicated in an independent cohort of 356 unrelated case-control individuals. The twins with major depressive disorder also show increased global variation in methylation in comparison with their unaffected co-twins. ZBTB20 plays an essential role in the specification of the Cornu Ammonis-1 field identity in the developing hippocampus, a region previously implicated in the development of major depressive disorder. Epigenetic study of MZ twins discordant for Major Depressive Disorder
Project description:Genome-wide MeDIP-Sequencing of 23 monozygotic twin pairs (n=46) from Australia discordant for major depressive disorder (MDD). MeDIP-seq of 23 monozygotic twin pairs discordant for major depressive disorder. MZ twin pairs were compared to identify significantly differently methylated sites associated with MDD.
Project description:Morphine and its pharmacological derivatives are the most prescribed analgesics for moderate to severe pain management. However, chronic use of morphine reduces pathogen clearance and induces bacterial translocation across the gut barrier. The enteric microbiome has been shown to play a critical role in the preservation of the mucosal barrier function and metabolic homeostasis. Here, we show for the first time, using bacterial 16s rDNA sequencing, that chronic morphine treatment significantly alters the gut microbial composition and induces preferential expansion of the gram-positive pathogenic and reduction of bile-deconjugating bacterial strains. A significant reduction in both primary and secondary bile acid levels was seen in the gut, but not in the liver with morphine treatment. Morphine induced microbial dysbiosis and gut barrier disruption was rescued by transplanting placebo-treated microbiota into morphine-treated animals, indicating that microbiome modulation could be exploited as a therapeutic strategy for patients using morphine for pain management. In this study, we establish a link between the two phenomena, namely gut barrier compromise and dysregulated bile acid metabolism. We show for the first time that morphine fosters significant gut microbial dysbiosis and disrupts cholesterol/bile acid metabolism. Changes in the gut microbial composition is strongly correlated to disruption in host inflammatory homeostasis13,14 and in many diseases (e.g. cancer/HIV infection), persistent inflammation is known to aid and promote the progression of the primary morbidity. We show here that chronic morphine, gut microbial dysbiosis, disruption of cholesterol/bile acid metabolism and gut inflammation; have a linear correlation. This opens up the prospect of devising minimally invasive adjunct treatment strategies involving microbiome and bile acid modulation and thus bringing down morphine-mediated inflammation in the host.