Downregulation of PTEN by sodium orthovanadate protects the myocardium against ischemia/reperfusion injury after chronic atorvastatin treatment.

Acute statin treatment has been reported to be critical in protecting the cardiac cells against ischemia/reperfusion injury by activating PI3K/Akt signal pathway. In vitro rat myocardial ischemia/reperfusion model, chronic statin treatment led to upregulation of phosphatase and tensin homolog (PTEN). This has been potentially indicated the correlation in PTEN and protective effect of statin on myocardium. In this current study, we evaluated the role of sodium orthovanadate a nonspecific inhibitor to PTEN and its correlation with atorvastatin on protecting myocardium against ischemia/reperfusion injury. We found a long-term statin treatment could increase the PTEN level, and this process was counteracted in the presence of sodium orthovanadate. However, the phosphotyrosine level was not affected by this statin. Besides, this process was mediated by Akt signaling since phosphorylated Akt level was altered by statin and sodium orthovanadate treatment. In a conclusion, this study showed a potential mechanism underlying PTEN-induced attenuation in long-term statin's therapeutic effect, which provided the new insight into the synergic role of PTEN and atorvastatin in protecting cardiac cells against ischemia/reperfusion injury.