MicroRNAs (miRNAs) are a recently discovered class of endogenous, small, noncoding RNAs that regulate gene expression. Although miRNAs are highly expressed in the heart, their roles in heart diseases are currently unclear. Using LC Sciences’ microarray analysis service, which is designed to detect the majority of mammalian miRNAs identified thus far, researchers from the University of Tennessee Health Science Center demonstrated that miRNAs are aberrantly expressed in hypertrophic mouse hearts. The time course of the aberrant miRNA expression was further identified in mouse hearts at 7, 14, and 21 days after aortic banding.
Nineteen of the most significantly dysregulated miRNAs were further confirmed by Northern blot and/or real-time polymerase chain reaction, in which miR-21 was striking because of its more than fourfold increase when compared with the sham surgical group. Similar aberrant expression of the most up-regulated miRNA, miR-21, was also found in cultured neonatal hypertrophic cardiomyocytes stimulated by angiotensin II or phenylephrine. Modulating miR-21 expression via antisense-mediated depletion (knockdown) had a significant negative effect on cardiomyocyte hypertrophy. The results suggest that miRNAs are involved in cardiac hypertrophy formation. miRNAs might be a new therapeutic target for cardiovascular diseases involving cardiac hypertrophy such as hypertension, ischemic heart disease, valvular diseases, and endocrine disorders.
Aberrant expression of miRNAs in mouse hypertrophic hearts
A: Time course changes of miRNAs that are highly expressed in mouse hearts and more than 30% dysregulated (down- or up-regulated) after aortic banding determined by microarray analysis. B: Confirmation of the aberrantly expressed miRNAs after aortic banding by qRT-PCR. C: Confirmation of the aberrantly expressed miRNAs after aortic banding by Northern blot. Note: miRNA levels in sham control hearts are defined as 100. *P < 0.05 compared with those in sham controls.
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miRNA Microarray Service – LC Sciences provides a microRNA (miRNA) expression profiling service using microarrays based on our in-house developed µParaflo® technology platform. We have standard arrays for all mature miRNAs of all species available in the latest version of the miRBase database (Release 21, July 2014). Our service is comprehensive and includes sample labeling, array hybridization, image data processing and in-depth data analysis. Two-three weeks after receiving your total RNA samples, we’ll send you both the raw and fully analyzed data. [Learn more…]
Reference
Cheng Y, Ji R, Yue J, Yang J, Liu X, Chen H, Dean DB, Zhang C. (2007) MicroRNAs Are Aberrantly Expressed in Hypertrophic Heart. Do They Play a Role in Cardiac Hypertrophy? Am J Pathol 170(6), 1831-40. [article]