title: Identification of microRNAs as a potential novel regulatory mechanism in HSD11B1 expression.
abstract: 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1, gene HSD11B1) converts glucocorticoid receptor-inert cortisone to receptor-active cortisol. Multiple evidence supports a causal role for 11β-HSD1 in the current obesity epidemic. In obese, HSD11B1 expression is increased in adipose tissue but typically decreased in liver, and the underlying tissue-specific mechanisms are largely unknown. In this context, we investigated a potential role of microRNAs (miRNAs). We used several miRNA target prediction tools to identify possible candidates and a publicly available miRNA expression atlas to further select candidates expressed in hepatocytes. Using a dual luciferase reporter assay, we identified three potential miRNAs, hsa-miR-340, -561 and -579, as potential negative regulators of HSD11B1 expression. Disruption of the corresponding microRNA response elements abolished repression of luciferase activity for hsa-miR-561 and -579, but not for hsa-miR-340. Furthermore, levels of firefly luciferase mRNA were not changed by miR-561 and -579, indicating a mechanism based on translational repression rather than mRNA degradation. Finally, we were able to detect both, miR-561 and -579, in human total liver RNA by reverse-transcription-polymerase chain reaction (RT-PCR). According to the presented results, miR-561 and -579 are likely to be involved in the tissue-specific regulation of HSD11B1 expression. Moreover, literature findings and a pathway enrichment analysis support a potential role of these two miRNAs in glucocorticoid metabolism and signalling and associated diseases.
authors.affiliation: Institute of Toxicology and Pharmacology for Natural Scientists, University Medical School Schleswig-Holstein, Campus Kiel, Brunswiker Str. 10, 24105 Kiel, Germany.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Han
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Staab-Weijnitz
authors.forename: Guangming
authors.initials: G
authors.lastname: Xiong
authors.forename: Edmund
authors.initials: E
authors.lastname: Maser
mesh_terms: D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1 / Q000235:genetics*; D020413:3' Untranslated Regions; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D015971:Gene Expression Regulation, Enzymologic; D017930:Genes, Reporter; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D020413:3' Untranslated Regions; C570046:MIRN340 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; C468386:HSD11B1 protein, human; D008156:Luciferases