Effect of blood-preserving time on expression of miRNAs in plasma of patients with unstable angina pectoris

LI Yun; SONG Yin-hong; LYU Yun-bo; QIN Qin

doi:10.3969/j.issn.1002-266X.2015.41.004

Abstract：Objective To investigate the effect of blood-preserving time on the expression of miRNAs ( miRNA-21, miRNA-24, miRNA-126, miRNA-146 and miRNA-223 ) in the plasma of patients with unstable angina pectoris ( UAP) , and to make sure the time window for checking their expression in plasma clinically.Methods Six UAP patients who accepted coronary angiography were selected as subjects.The peripheral blood ( PB) samples of the pa-tients were collected in EDTA anticoagulant tubes and separated into 6 tubes (2 ML in each).During the six tubes, the plasma of 3 tubes were separated, and was preserved at 4℃, the other 3 tubes were preserved at 4 ℃.The levels of miRNAs were detected in the 3 tubes at the moment of centrifugation ( 0 h) , 24 h and one week later by real-time fluorescent quantitative PCR.The same procedures were conducted in the other 3 tubes of whole blood after the plasma wascollected.ThelevelsofplasmamiRNAswerecomparedatdifferenttimepoints.Results ①Theconcentrations of miRNA-21, miRNA-24, miRNA-126 and miRNA-223 in plasma were decreased significantly after being stored for 24 h as compared with the moment of 0 h(all P<0.05).The concentrations of all the 5 miRNAs in plasma were de-creased significantly after being stored for one week as compared with that of 24 h( P<0.05) .② The concentration of miRNA-21 in plasma was decreased significantly after being stored for 4 hours as compared with that of 0 h( P<0.05),and the concentrations of 5 miRNAs in plasma were decreased significantly after being stored for 24 h (P<0.05).Conclusion There are differences among the stabilities of different miRNAs in plasma of UAP patients, and miRNA-21 must be examined immediately owing to its poor stability.