Temporal Changes in MicroRNA Expression in Blood Leukocytes from Patients with the Acute Respiratory Distress Syndrome. Homo sapiens

MicroRNA (miRNA) control gene transcription by binding to and repressing the translation of messenger RNA (mRNA). Their role in the acute respiratory distress syndrome (ARDS) is undefined. Blood leukocytes from 51 patients enrolled in a prior randomized trial of corticosteroids for ARDS were analyzed. After screening eight patients with microarrays for increased miRNA expression, 25 miRNAs were selected for further analysis using RT-PCR in all 51 patients on days 0, 3 and 7. Overall design: Randomized, double blind, placebo-controlled trial compared placebo and standard supportive therapy (usual care) to standard therapy plus early low-dose methylprednisolone infusion (1 mg/kg/day for 14 days and then tapered over 2 wks) using a 1:2 randomization schedule in intubated patients enrolled within 72 hours of ARDS onset. Fifty-one patients (37 treated with corticosteroids and 14 with standard care alone) of the 91 patients enrolled in the original study had blood leukocyte samples available for analysis. Four patients samples from each group were used for microarray analysis at day 0 and day 3.