Decreased KCNE2 expression participates in the development of cardiac hypertrophy / 中国病理生理杂志

ABSTRACT

AIM:To investigate whether KCNE 2 participates in the development of pathological hypertrophy .METHODS:Bidirectional ma-nipulations of KCNE2 expression were performed by adenoviral overexpression of KCNE 2 or knockdown of KCNE2 with RNA interfer-ence in PE-induced neonatal rat ventricular myocytes .Then overexpression of KCNE 2 in mouse model of left ventricular hypertrophy in-duced by transverse aortic constriction (TAC) by ultrasound microbubble-mediated gene transfer were used to detect the therapeutic function of KCNE2 in the development of hypertrophy .RESULTS:KCNE2 expression was significantly decreased in PE-induced hy-pertrophic cardiomyocytes and in hypertrophic hearts produced by TAC .Knockdown of KCNE2 in cardiomyocytes reproduced hypertro-phy, whereas overexpression of KCNE2 attenuated PE-induced cardiomyocyte hypertrophy .Knockdown of KCNE2 increased calcineurin activity and nuclear NFAT protein level , and pretreatment with nifedipine or FK 506 attenuated decreased KCNE 2-induced cardiomyo-cyte hypertrophy .Overexpression of KCNE 2 in heart by ultrasound microbubble-mediated gene transfer suppressed the development of hypertrophy and activation of calcineurin-NFAT and MAPK pathways in TAC mice .CONCLUSION:These findings demonstrate that cardiac KCNE2 expression is decreased and contributes to the development of hypertrophy via activation of calcineurin -NFAT and MAPK pathways .