MicroRNA profiling in ischemic injury of the gracilis muscle in rats

Abstract

BackgroundTo profile the expression of microRNAs (miRNAs) and their potential target genes in the gracilis muscles following ischemic injury in rats by monitoring miRNA and mRNA expression on a genome-wide basis.MethodsFollowing 4 h of ischemia and subsequent reperfusion for 4 h of the gracilis muscles, the specimens were analyzed with an Agilent rat miRNA array to detect the expressed miRNAs in the experimental muscles compared to those from the sham-operated controls. Their expressions were subsequently quantified by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) to determine their expression pattern after different durations of ischemia and reperfusion. In addition, the expression of the mRNA in the muscle specimens after 4 h of ischemia and reperfusion for 1, 3, 7, and 14 d were detected with the Agilent Whole Rat Genome 4 × 44 k oligo microarray. A combined approach using a computational prediction algorithm that included miRanda, PicTar, TargetScanS, MirTarget2, RNAhybrid, and the whole genome microarray experiment was performed by monitoring the mRNA:miRNA association to identify potential target genes.ResultsThree miRNAs (miR-21, miR-200c, and miR-205) of 350 tested rat miRNAs were found to have an increased expression in the miRNA array. Real-time RT-PCR demonstrated that, with 2-fold increase after 4 h of ischemia, a maximum 24-fold increase at 7 d, and a 7.5-fold increase at 14 d after reperfusion, only the miR-21, but not the miR-200c or miR-205 was upregulated throughout the experimental time. In monitoring the target genes of miR-21 in the expression array at 1, 3, 7, 14 d after reperfusion, with persistent expression throughout the experiment, we detected the same 4 persistently downregulated target genes (Nqo1, Pdpn, CXCL3, and Rad23b) with the prediction algorithms miRanda and RNAhybrid, but no target gene was revealed with PicTar, TargetScanS, and MirTarget2.ConclusionsThis study revealed 3 upregulated miRNAs in the gracilis muscle following ischemic injury and identified 4 potential target genes of miR-21 by examining miRNAs and mRNAs expression patterns in a time-course fashion using a combined approach with prediction algorithms and a whole genome expression array experiment.

Delayed ischemic preconditioning contributes to renal protection by upregulation of miR-21

“…37 Several miRNAs were differentially regulated in hippocampi following global ischemia 38 and gracilis muscles in ischemic injury. 39 Yin et al showed that IPC in the heart resulted in upregulated miR-1, miR-21, and miR-24 expression. 23 Abundance of miR-23a, miR-326, miR-346, and miR-370 was altered in hepatic IPC.…”

Protective effect of edaravone for tourniquet-induced ischemia-reperfusion injury on skeletal muscle in murine hindlimb

“…Although the pathophysiology of I/R injuries has not been fully elucidated due to complex interactions of inflammatory and immunologic signaling pathways [8], it is clear that accumulated free radicals and anaerobic metabolites during ischemia cause the migration of white blood cells and the release of inflammatory factors such as interleukin and free radicals in the reperfusion phase [9-13]. These compounds eventually damage muscle tissues, resulting in irrecoverable muscle damage and general complications [14-16].…”

MicroRNA-155 aggravates ischemia–reperfusion injury by modulation of inflammatory cell recruitment and the respiratory oxidative burst

“…In how far miRNAs are involved in IRI remains largely unclear: While first studies suggest a potential modulatory function of these small RNAs, reporting both aggravating as well as protective effects [16,19,53], other studies argue against an important pathophysiological role of miRNAs in IRI and ischemic postconditioning in larger mammals [3].…”