Browsing by Subject "Carbon Monoxide"

MicroRNAs are small single-stranded RNA molecules that regulate gene expression by silencing the translation of messenger RNAs. They have the ability to silence translation of multiple different messenger RNAs simultaniously and have been shown to have an important role in the formation and maintaining homeostatsis of several tissue types. The regenerative ability of the human heart after myocardial injury is limited, which often leads to adverse changes in cardiac structure and function. This is why molecules that enhance the regenerative and reparative abilities of cardiomyocytes, such as carbon monoxide, are of special interest. Carbon monoxide protects cardiomyocytes from apoptosis and prevents their proliferation. One proposed modulator of these effects is the p38 mitogen-activated protein kinase (p38 MAPK). We studied the effects of carbon monoxide releasing molecule-3 (CORM-3) on cardiac recovery after myocardial infarction in adult rats and how it effects the expression of microRNAs miR-133a, miR-133b, miR-206 and miR-208. In addition, we studied the effects of carbon monoxide releasing molecule-A1 (CORM-A1) and inhibition of p38 MAPK on neonatal rat cardiomyocyte proliferation and apoptosis. We showed that CORM-3 improves cardiac recovery after myocardial infarction by increasing the amount of cardiomyocytes in the infarct area and improving the cardiac function of the left ventricle. Additionally, we showed that inhibiting p38 MAPK increases proliferation in neonatal rat cardiomyocytes. The beneficial effects of carbon monoxide on cardiac recovery after myocardial injury are well known. However, the exact mechanisms of its actions in cardiomyocytes remain poorly known. MicroRNAs might at least partly mediate these effects as CORM-3 increased their expression in rat hearts. The potential pathways between carbon monoxide and microRNA require still further research.