The involvement of phosphatase and tensin homolog deleted on chromosome ten (PTEN) in the regulation of inflammation following coronary microembolization.

Growing evidence shows that phosphatase and tensin homolog deleted on chromosome ten (PTEN) is involved in regulating inflammation in different pathological conditions. Therefore, we hypothesized that the upregulation of PTEN correlates with the impairment of cardiac function in swine following coronary microembolization (CME). To possibly disclose an anti-inflammatory effect of PTEN, we induced swine CME by injecting inertia plastic microspheres (42 μm in diameter) into the left anterior descending coronary artery and analyzed the myocardial tissue by immunochemistry, qRT-PCR and western blot analyses. In addition, we downregulated PTEN using siRNA. Following CME, PTEN mRNA and protein levels were elevated as early as 3 h, peaked at 12 h, and then continuously decreased at 24 h and 48 h but remained elevated. Through linear correlation analysis, the PTEN protein level positively correlated with cTnI and TNF-α but was negatively correlated with LVEF. Furthermore, PTEN siRNA reduced the microinfarct volume, improved cardiac function (LVEF), reduced the release of cTnI, and suppressed PTEN and TNF-α protein expression. This study demonstrated, for the first time, that PTEN is involved in CME-induced inflammatory injury. The data generated from this study provide a rationale for the development of PTEN-based anti-inflammatory strategies.