title: Effects of remote ischemic preconditioning and myocardial ischemia on microRNA-1 expression in the rat heart in vivo.
abstract: Remote ischemic preconditioning (RIPC) is an easily applicable method for protecting the heart against a subsequent ischemia and reperfusion (I/R) injury. However, the exact molecular mechanisms underlying RIPC are unknown. We examined the involvement of microRNAs (miRNAs) and in particular the expression of miRNA-1 (miR-1) in RIPC and myocardial ischemia. Remote ischemic preconditioning was conducted by four cycles of 5-min bilateral hind-limb ischemia in male Wistar rats. Cardiac ischemia was induced by ligation of the left anterior descending coronary artery for 35 min followed by 2 or 6 h of reperfusion. MicroRNA expression was analyzed by Taqman miRNA arrays and quantitative polymerase chain reaction assays. Luciferase assays were performed to validate the miR-1 target gene brain-derived neurotrophic factor (BDNF). Brain-derived neurotrophic factor mRNA and protein levels were analyzed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Remote ischemic preconditioning led to a differential expression of miRNAs. The most abundant cardiac miRNA, miR-1, was downregulated by RIPC without following ischemia as well as after I/R and RIPC followed by I/R after 2 h of reperfusion. After 6 h of reperfusion, RIPC led to an upregulation of miR-1, whereas ischemia had no effect on miR-1 expression. Luciferase assays confirmed the interaction of miR-1 with BDNF, a protein that has been shown to exert cardioprotective effects. Brain-derived neurotrophic factor protein levels in rat hearts measured by enzyme-linked immunosorbent assay were not significantly altered after 2 or 6 h of reperfusion in all intervention groups. Remote ischemic preconditioning leads to changes in the expression levels of the most abundant cardiac miRNA, miR-1. MicroRNA 1 levels did not correlate with protein levels of BDNF, a known miR-1 target, in vivo. Further studies are needed to explore the biological significance of changes in miR-1 expression levels and the potential interaction with BDNF in RIPC-induced cardioprotection.
authors: *Department of Anesthesiology, University Hospital Duesseldorf, Duesseldorf, Germany; and †Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Timo
authors: T
authors: Brandenburger
authors: Hilbert
authors: H
authors: Grievink
authors: Nicole
authors: N
authors: Heinen
authors: Franziska
authors: F
authors: Barthel
authors: Ragnar
authors: R
authors: Huhn
authors: Friederike
authors: F
authors: Stachuletz
authors: Malte
authors: M
authors: Kohns
authors: Benedikt
authors: B
authors: Pannen
authors: Inge
authors: I
authors: Bauer
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics / Q000378:metabolism; D019295:Computational Biology; D004195:Disease Models, Animal; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D057809:HEK293 Cells; D006439:Hemodynamics; D006614:Hindlimb / Q000098:blood supply*; D006801:Humans; D019194:Ischemic Preconditioning / Q000379:methods*; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D015428:Myocardial Reperfusion Injury / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D017208:Rats, Wistar; D013997:Time Factors; D014162:Transfection
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C542191:MIRN1 microRNA, rat; D035683:MicroRNAs; D012333:RNA, Messenger; D008156:Luciferases