title: MicroRNAs may mediate the down-regulation of neurokinin-1 receptor in chronic bladder pain syndrome.
abstract: Bladder pain syndrome (BPS) is a clinical syndrome of pelvic pain and urinary urgency-frequency in the absence of a specific cause. Investigating the expression levels of genes involved in the regulation of epithelial permeability, bladder contractility, and inflammation, we show that neurokinin (NK)1 and NK2 tachykinin receptors were significantly down-regulated in BPS patients. Tight junction proteins zona occludens-1, junctional adherins molecule -1, and occludin were similarly down-regulated, implicating increased urothelial permeability, whereas bradykinin B(1) receptor, cannabinoid receptor CB1 and muscarinic receptors M3-M5 were up-regulated. Using cell-based models, we show that prolonged exposure of NK1R to substance P caused a decrease of NK1R mRNA levels and a concomitant increase of regulatory micro(mi)RNAs miR-449b and miR-500. In the biopsies of BPS patients, the same miRNAs were significantly increased, suggesting that BPS promotes an attenuation of NK1R synthesis via activation of specific miRNAs. We confirm this hypothesis by identifying 31 differentially expressed miRNAs in BPS patients and demonstrate a direct correlation between miR-449b, miR-500, miR-328, and miR-320 and a down-regulation of NK1R mRNA and/or protein levels. Our findings further the knowledge of the molecular mechanisms of BPS, and have relevance for other clinical conditions involving the NK1 receptor.
authors.affiliation: Department of Cell Biology, Institute of Anatomy, University of Bern, 3000 Bern 9, Switzerland.
authors.forename: Veronica
authors.initials: V
authors.lastname: Sanchez Freire
authors.forename: Fiona C
authors.initials: FC
authors.lastname: Burkhard
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Kessler
authors.forename: Annette
authors.initials: A
authors.lastname: Kuhn
authors.forename: Annette
authors.initials: A
authors.lastname: Draeger
authors.forename: Katia
authors.initials: K
authors.lastname: Monastyrskaya
mesh_terms: D000328:Adult; D000368:Aged; D001483:Base Sequence; D001706:Biopsy; D002478:Cells, Cultured; D018856:Cystitis, Interstitial / Q000150:complications / Q000235:genetics* / Q000473:pathology; D030561:Databases, Nucleic Acid; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics*; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D008969:Molecular Sequence Data; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000378:metabolism; D010539:Permeability / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018040:Receptors, Neurokinin-1 / Q000235:genetics* / Q000378:metabolism; D013373:Substance P / Q000494:pharmacology; D013577:Syndrome; D019459:Urothelium / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger; D018040:Receptors, Neurokinin-1; D013373:Substance P