title: Circulating microRNAs as novel biomarkers for platelet activation.
abstract: BACKGROUND
  MicroRNA (miRNA) biomarkers are attracting considerable interest. Effects of medication, however, have not been investigated thus far.
  
  
  OBJECTIVE
  To analyze changes in plasma miRNAs in response to antiplatelet therapy.
  
  
  RESULTS
  Profiling for 377 miRNAs was performed in platelets, platelet microparticles, platelet-rich plasma, platelet-poor plasma, and serum. Platelet-rich plasma showed markedly higher levels of miRNAs than serum and platelet-poor plasma. Few abundant platelet miRNAs, such as miR-24, miR-197, miR-191, and miR-223, were also increased in serum compared with platelet-poor plasma. In contrast, antiplatelet therapy significantly reduced miRNA levels. Using custom-made quantitative real-time polymerase chain reaction plates, 92 miRNAs were assessed in a dose-escalation study in healthy volunteers at 4 different time points: at baseline without therapy, at 1 week with 10 mg prasugrel, at 2 weeks with 10 mg prasugrel plus 75 mg aspirin, and at 3 weeks with 10 mg prasugrel plus 300 mg aspirin. Findings in healthy volunteers were confirmed by individual TaqMan quantitative real-time polymerase chain reaction assays (n=9). Validation was performed in an independent cohort of patients with symptomatic atherosclerosis (n=33), who received low-dose aspirin at baseline. Plasma levels of platelet miRNAs, such as miR-223, miR-191, and others, that is, miR-126 and miR-150, decreased on further platelet inhibition.
  
  
  CONCLUSIONS
  Our study demonstrated a substantial platelet contribution to the circulating miRNA pool and identified miRNAs responsive to antiplatelet therapy. It also highlights that antiplatelet therapy and preparation of blood samples could be confounding factors in case-control studies relating plasma miRNAs to cardiovascular disease.
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Willeit
authors.forename: Anna
authors.initials: A
authors.lastname: Zampetaki
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Dudek
authors.forename: Dorothee
authors.initials: D
authors.lastname: Kaudewitz
authors.forename: Alice
authors.initials: A
authors.lastname: King
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Kirkby
authors.forename: Roxanne
authors.initials: R
authors.lastname: Crosby-Nwaobi
authors.forename: Marianna
authors.initials: M
authors.lastname: Prokopi
authors.forename: Ignat
authors.initials: I
authors.lastname: Drozdov
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Langley
authors.forename: Sobha
authors.initials: S
authors.lastname: Sivaprasad
authors.forename: Hugh S
authors.initials: HS
authors.lastname: Markus
authors.forename: Jane A
authors.initials: JA
authors.lastname: Mitchell
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Warner
authors.forename: Stefan
authors.initials: S
authors.lastname: Kiechl
authors.forename: Manuel
authors.initials: M
authors.lastname: Mayr
mesh_terms: D000328:Adult; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D015415:Biomarkers; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D001800:Blood Specimen Collection / Q000379:methods; D002340:Carotid Artery Diseases / Q000188:drug therapy; D016022:Case-Control Studies; D002986:Clinical Trials as Topic; D015986:Confounding Factors, Epidemiologic; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis / Q000097:blood* / Q000235:genetics; D010879:Piperazines / Q000008:administration & dosage / Q000494:pharmacology; D010949:Plasma / Q000378:metabolism*; D015539:Platelet Activation / Q000235:genetics; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D000068799:Prasugrel Hydrochloride; D060888:Real-Time Polymerase Chain Reaction; D044967:Serum / Q000378:metabolism*; D013876:Thiophenes / Q000008:administration & dosage / Q000494:pharmacology; D055815:Young Adult
chemical_list: D015415:Biomarkers; D035683:MicroRNAs; D010879:Piperazines; D010975:Platelet Aggregation Inhibitors; D013876:Thiophenes; D000068799:Prasugrel Hydrochloride; D001241:Aspirin