miRNA array experiment of NC-Exo and GATA4-Exo

Exosomes carry cell-specific proteins or mRNAs/miRNAs that mediate the functional effect of exosomes. To investigate whether miRNAs within GATA4-Exo are important for their cardioprotective effects, we utilized an unbiased approach by performing an exosomal miRNA array analysis. Total RNA was extracted from CDCs-Exo by using a Qiagen miRNeasy Mini Kit. Global expression patterns of miRNAs were then examined by using Affymetrix GeneChip miRNA 4.0 arrays.Expression data were generated by using Affymetrix Expression Console software and normalized according to the MAS5 method. The RVM t test was applied to filter the differentially expressed genes for the control and experimental groups. Differentially expressed genes were defined based on a P-value threshold and fold-change analysis. Exosomes were obtained from the CDC and CDCGATA4 culture supernatants by ultracentrifugation. Exosomes were harvested from CDCs by ultracentrifugation. miRNA arrays were performed to test the differential miRNA expression between exosomes derived from GATA4-overexpressing CDCs (GATA4-Exo) and control CDCs (NC-Exo). Microarray analysis revealed significantly increased and decreased miRNAs expression in GATA4-Exo.