Tripartite motif­containing 14 may aggravate cardiac hypertrophy via the AKT signalling pathway in neonatal rat cardiomyocytes and transgenic mice.

ABSTRACT

Tripartite motif­containing 14 (TRIM14) is an E3 ubiquitin ligase that primarily participates in the natural immune response and in tumour development via ubiquitination. However, the role of TRIM14 in cardiac hypertrophy is not currently clear. The present study examined the role of TRIM14 in cardiac hypertrophy and its potential molecular mechanism. TRIM14 was overexpressed in neonatal rat cardiomyocytes using adenovirus and cardiomyocyte hypertrophy was induced using phenylephrine (PE). Cardiomyocyte hypertrophy was assessed by measuring cardiomyocyte surface area and markers of hypertrophy. In addition, TRIM14­transgenic (TRIM14­TG) mice were created and cardiac hypertrophy was induced using transverse aortic constriction (TAC). Cardiac function, heart weight­to­body weight ratio (HW/BW), cardiomyocyte cross­sectional area, cardiac fibrosis and hypertrophic markers were further examined. The expression of AKT signalling pathway­related proteins was detected. TRIM14 overexpression in cardiomyocytes promoted PE­induced increases in cardiomyocyte surface area and hypertrophic markers. TRIM14­TG mice developed worse cardiac function, greater HW/BW, cross­sectional area and cardiac fibrosis, and higher levels of hypertrophic markers in response to TAC. TRIM14 overexpression also increased the phosphorylation levels of AKT, GSK­3ß, mTOR and p70S6K in vivo and in vitro. To the best our knowledge, the present study was the first to reveal that overexpression of TRIM14 aggravated cardiac hypertrophy in vivo and in vitro, which may be related to activation of the AKT signalling pathway.