Molecular mechanism of c-jun antisense gene transfection in alleviating injury of cardiomyocytes treated with burn serum and hypoxia.

To explore the molecular mechanism of c-jun antisense gene transfection in alleviating injury of cardiomyocytes treated with burn serum and hypoxia, burn serum was collected from Wistar rats inflicted with 30% third-degree burn of the total body surface area. The cardiomyocytes of neonatal Wistar rats were cultured and then treated with burn serum and hypoxia (a gas mixture containing 1% O2). The constructed c-jun antisense gene recombinant was transfected into the cardiomyocytes of neonatal Wistar rats. TdT-mediated d-utp nick end labeling (TUNEL) was adopted to examine cardiomyocyte apoptosis. Morphological changes of cardiomyocytes were observed under an optic-microscope and an electron-microscope. Expression of troponin T and beta-tubulin protein, c-jun protein, protein kinase Ca (PKCa), and c-jun N-terminal kinase (JNK) were assayed with Western blot in the transfected and non-transfected groups. The morphology of cardiomyocytes in the non-transfected group changed explicitly, but the change was not so obvious in the transfected cardiomyocytes. The expression of beta-tubulin and troponin increased significantly in the transfected group as compared with the non-transfected group. In the non-transfected group, numbers of apoptotic cardiomyocytes were significantly higher than in the transfected group. The c-jun protein, PKCa, and JNK were significantly expressed in the non-transfected group, and they reached a maximum at the 24th hour after cardiomyocytes were treated with burn serum and hypoxia. In the transfected group, however, expressions of c-jun protein, PKCa, and JNK decreased significantly compared with the non-transfected group. The c-jun antisense gene recombinant transfection alleviates injury to cardiomyocytes treated with burn serum and hypoxia, probably through low expression of PKCa and JNK.