E3-ubiquitin ligase TRIM6 aggravates myocardial ischemia/reperfusion injury via promoting STAT1-dependent cardiomyocyte apoptosis.

ABSTRACT: Cardiomyocyte apoptosis is a major cause of myocardial ischemia/reperfusion (MI/R) injury, in which the activation of the signal transducer and activator of transcription 1 (STAT1) plays an important role. The E3-ubiquitin ligase TRIM6 has been implicated in regulating STAT1 activity, however, whether it is associated with MI/R injury and the underlying mechanism are not determined. In this study, by investigating a mouse MI/R injury model, we show that TRIM6 expression is induced in mouse heart following MI/R injury. Additionally, TRIM6 depletion reduces and its overexpression increases myocardial infarct size, serum creatine phosphokinase (CPK) level and cardiomyocyte apoptosis in mice subjected to MI/R injury, indicating that TRIM6 functions to aggravate MI/R injury. Mechanistically, TRIM6 promotes IKK?-dependent STAT1 activation, and the inhibition of IKK? or STAT1 with the specific inhibitor, CAY10576 or fludarabine, abolishes TRIM6 effects on cardiomyocyte apoptosis and MI/R injury. Similarly, TRIM6 mutant lacking the ability to ubiquitinate IKK? and induce IKK?/STAT1 activation also fails to promote cardiomyocyte apoptosis and MI/R injury. Thus, these results suggest that TRIM6 aggravates MI/R injury through promoting IKK?/STAT1 activation-dependent cardiomyocyte apoptosis, and that TRIM6 might represent a novel therapeutic target for alleviating MI/R injury.

SUBMITTER: Zeng G 

PROVIDER: S-EPMC6594808 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature