title: Chronic corticosterone-mediated dysregulation of microRNA network in prefrontal cortex of rats: relevance to depression pathophysiology.
abstract: Stress plays a major role in inducing depression, which may arise from interplay between complex cascades of molecular and cellular events that influence gene expression leading to altered connectivity and neural plasticity. In recent years, microRNAs (miRNAs) have carved their own niche owing to their innate ability to induce disease phenotype by regulating expression of a large number of genes in a cohesive and coordinated manner. In this study, we examined whether miRNAs and associated gene networks have a role in chronic corticosterone (CORT; 50 mg  kg(-1) × 21 days)-mediated depression in rats. Rats given chronic CORT showed key behavioral features that resembled depression phenotype. Expression analysis revealed differential regulation of 26 miRNAs (19 upregulated, 7 downregulated) in prefrontal cortex of CORT-treated rats. Interaction between altered miRNAs and target genes showed dense interconnected molecular network, in which multiple genes were predicated to be targeted by the same miRNA. A majority of altered miRNAs showed binding sites for glucocorticoid receptor element, suggesting that there may be a common regulatory mechanism of miRNA regulation by CORT. Functional clustering of predicated target genes yielded disorders such as developmental, inflammatory and psychological that could be relevant to depression. Prediction analysis of the two most prominently affected miRNAs miR-124 and miR-218 resulted into target genes that have been shown to be associated with depression and stress-related disorders. Altogether, our study suggests miRNA-mediated novel mechanism by which chronic CORT may be involved in depression pathophysiology.
authors.affiliation: Department of Psychiatry and Behavioral Neurobiology, UAB Mood Disorder Program, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Dwivedi
authors.affiliation: Department of Psychiatry and Behavioral Neurobiology, UAB Mood Disorder Program, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: B
authors.initials: B
authors.lastname: Roy
authors.affiliation: Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: G
authors.initials: G
authors.lastname: Lugli
authors.affiliation: Department of Psychiatry and Behavioral Neurobiology, UAB Mood Disorder Program, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: H
authors.initials: H
authors.lastname: Rizavi
authors.affiliation: Department of Psychiatry and Behavioral Neurobiology, UAB Mood Disorder Program, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: N R
authors.initials: NR
authors.lastname: Smalheiser
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003345:Corticosterone / Q000008:administration & dosage* / Q000097:blood; D003866:Depressive Disorder / Q000235:genetics / Q000503:physiopathology*; D004195:Disease Models, Animal; D053263:Gene Regulatory Networks / Q000235:genetics*; D008297:Male; D035683:MicroRNAs / Q000097:blood / Q000235:genetics*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000235:genetics
chemical_list: D035683:MicroRNAs; D003345:Corticosterone