TRIM27 protects against cardiac ischemia-reperfusion injury by suppression of apoptosis and inflammation via negatively regulating p53.

Myocardial ischemia/reperfusion (MI/R) has high morbidity and mortality worldwide, but the underlying mechanisms have not been entirely understood. TRIM27 is one of the Tri-domain proteins (TRIM) family proteins with crucial roles in numerous life processes. In the study, we attempted to explore the effects of heart-conditional knockout of TRIM27 (TRIM27cKO) on MI/R progression both in vivo and in vitro. Our results showed that TRIM27 was strongly decreased in murine hearts with MI/R injury and in cardiomyocytes with hypoxic reoxygenation (HR) treatment. TRIM27cKO could further accelerate the infarction size and cardiac dysfunction in MI/R mice. Function study demonstrated that heart-selective TRIM27 deletion significantly aggravated apoptosis in hearts of MI/R mice through enhancing Caspase-3 activities. Moreover, inflammatory response due to MI/R injury was remarkably exacerbated in TRIM27cKO mice by strengthening nuclear factor κB (NF-κB) activation. In addition, p53 expression levels were dramatically up-regulated in hearts of MI/R mice and cardiomyocytes with HR treatment, which were further aggravated by TRIM27cKO. Intriguingly, we found that TRIM27 could interact with p53 and promote its ubquitination. Of note, suppressing p53 remarkably ameliorated TRIM27cKO-intensified apoptotic cell death and inflammation in HR-treated cardiomyocytes. Taken together, all these findings revealed that TRIM27/p53 axis may be involved in MI/R progression, and thus could be a therapeutic target for this disease treatment.