title: Peripheral whole blood microRNA alterations in major depression and bipolar disorder.
abstract: Major depression (MD) and bipolar disorder (BD) are severe and potentially life-threating mood disorders whose etiology is to date not completely understood. MicroRNAs (miRNAs) are small non-coding RNAs that regulate protein synthesis post-transcriptionally by base-pairing to target gene mRNAs. Growing evidence indicated that miRNAs might play a key role in the pathogenesis of neuropsychiatric disorders and in the action of psychotropic drugs. On these bases, in this study we evaluated the expression levels of 1733 mature miRNAs annotated in miRBase v.17, through a microarray technique, in the blood of 20 MD and 20 BD patients and 20 healthy controls, in order to identify putative miRNA signatures associated with mood disorders. We found that 5 miRNAs (hsa-let-7a-5p, hsa-let-7d-5p, hsa-let-7f-5p, hsa-miR-24-3p and hsa-miR-425-3p) were specifically altered in MD patients and 5 (hsa-miR-140-3p, hsa-miR-30d-5p, hsa-miR-330-5p, hsa-miR-378a-5p and hsa-miR-21-3p) in BD patients, whereas 2 miRNAs (hsa-miR-330-3p and hsa-miR-345-5p) were dysregulated in both the diseases. The bioinformatic prediction of the genes targeted by the altered miRNAs revealed the possible involvement of neural pathways relevant for psychiatric disorders. In conclusion, the observed results indicate a dysregulation of miRNA blood expression in mood disorders and could indicate new avenues for a better understanding of their pathogenetic mechanisms. The identified alterations may represent potential peripheral biomarkers to be complemented with other clinical and biological features for the improvement of diagnostic accuracy.
authors.affiliation: Genetics Unit, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Maffioletti
authors.affiliation: Biological Psychiatry Unit, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy; Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Cattaneo
authors.affiliation: A.O.U. San Luigi Gonzaga Hospital, S.C.D.U. Psychiatric Service, University of Turin, Orbassano, Turin, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Rosso
authors.affiliation: A.O.U. San Luigi Gonzaga Hospital, S.C.D.U. Psychiatric Service, University of Turin, Orbassano, Turin, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Maina
authors.affiliation: Genetics Unit, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Maj
authors.affiliation: Genetics Unit, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy; Department of Molecular and Translational Medicine, University of Brescia, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Gennarelli
authors.affiliation: Department of Pharmacological and Biomolecular Science, University of Milan, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Tardito
authors.affiliation: Genetics Unit, IRCCS Centro S. Giovanni di Dio, Fatebenefratelli, Brescia, Italy; Faculty of Psychology, eCampus University, Novedrate, Como, Italy. Electronic address: lbocchio@fatebenefratelli.eu.
authors.forename: Luisella
authors.initials: L
authors.lastname: Bocchio-Chiavetto
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001714:Bipolar Disorder / Q000097:blood / Q000175:diagnosis*; D003865:Major Depressive Disorder / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood* / Q000235:genetics; D008875:Middle Aged
chemical_list: D015415:Biomarkers; D035683:MicroRNAs
keywords: Biomarker; Bipolar disorder; Blood; Let-7; Major depression; MicroRNA