Rosuvastatin Treatment Activates JAK-STAT Pathway and Increases Efficacy of Allogeneic Mesenchymal Stem Cell Transplantation in Infarcted Hearts

Background: Widespread death of implanted cells hampers the development of stem cell therapy for acute myocardial infarction (AMI). Our previous studies indicated that statins can protect implanted mesenchymal stem cells (MSCs) against the post-infarct microenvironment, thus increasing the therapeutic effect. However, the underlying mechanisms are unclear. The JAK-STAT pathway participates in regulation of stress responses of the myocardium to various insults. This study aimed to detect whether rosuvastatin (ROSU) facilitates the survival, engraftment, and differentiation of allogeneic bone marrow-derived MSCs in the post-infarct heart via the JAK-STAT signaling pathway. Methods and Results: Female Sprague-Dawley rats were randomized into 5 groups: AMI (control), ROSU gavage (group R), MSCs transplantation (group M), MSCs and ROSU (group M+R), or MSCs, ROSU and a JAK2 inhibitor AG-490 (group M+R+AG). MSCs from male rats were injected into the myocardium 1 week after AMI. Cardiac function and histology, as well as the expression of Y-chromosomal genes and JAK-STAT signaling proteins, were examined at 4 weeks after transplantation. Better functional recovery, increased survival and differentiation of MSCs occurred in group M+R. Furthermore, phosphorylation of JAK2 and STAT3 was higher in group M+R. The effects of ROSU, as well as of activated JAK-STAT proteins, could be attenuated by AG-490. Conclusions: ROSU treatment improves the efficacy of stem cell transplantation in infarcted hearts by activation of the JAK2-STAT3 signaling pathway. (Circ J 2011; 75: 1476-1485)