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Background: The post-transcriptional regulators of gene expression,microRNAs(miRNAs),play a vitro role in multiple cellular processes.Cartilage endplate(CEP)degeneration always combined withthe changes of mechanical environment.We hypothesized that miRNAs may participate in mechanical response,and therefore alternatively expressed in normal and degenerated CEP after cyclic stretch. Methods: CEPs from two patients at the age of 17(normal sample)and 72(degenerated sample)were selected,chondrocytes were isolated and then equibiaxially stretched to 10%substrate elongation at 0.5Hz for 4 hours per day,7 days in a row,or collected as un-stretched controls.Total RNAs were extracted and subjected to the ExiqonmiRCURYTM LNA Array to identify differentially miRNAs expression profiles.The data were then validated by quantitativereverse transcription polymerase chain reaction(qRT-PCR),and performed to bioinformatics analysis. Results: In total,76 specific miRNAs were alternatively regulated at least 3-fold change over un-stretched control.38miRNAs were up-regulated while 31miRNAs down-regulatedin both samples.Interestingly,6 miRNAswere down-regulated in normal sample but up-regulated in degenerated sample,while only 1miRNAs were up-regulated in normal sample but down-regulated in degenerated sample.Gene ontology(GO)classification showed that the predicted target genes of ten selected miRNAs were involved in cell proliferation,differentiation,apoptosis and autophagy.Thirteen of the 76 miRNAs had previously been reported to response mechanical stimulation,and commonly showed the mechanotransduction pathway. Conclusion: In conclusion,miRNAs were distinctly expressed in normal and degenerated CEP after cyclic stretch.Our results provided the basis for further research of the molecular biomechanics in degenerated human CEP.