Herpud1 suppress angiotensin II induced hypertrophy in cardiomyocytes.

Purpose: The purpose of this study was to analyze the role of homocysteine-responsive endoplasmic reticulum-resident ubiquitin-like domain member 1 (Herpud1) gene in the development of cardiomyocyte hypertrophy.

Method: In order to examine the effect of suppressing Herpud1 expression, Herpud1 small interfering RNA (siRNA) was introduced into H9C2 cells, which are cell lines derived from rat myocardium, and the degree of Herpud1 protein expression and cell hypertrophy in the Herpud1 siRNA-transfected group and the control group was compared by immunostaining 48 h after Herrpud1 siRNA introduction. To examine whether hypertrophy induced by angiotensin II (Ang II) can be suppressed by the overexpression of Herpud1, the green fluorescent protein (GFP)-Herpud1 plasmid was introduced into H9C2 cells, and the degree of cell hypertrophy was examined in the GFP-Herpud1-and control groups for 48 h. Nuclear translocation of nuclear factor of activated T-cells, cytoplasmic 4 (NFATc4), a transcription factor for hypertrophic genes, was also examined.

Results: [1] Herpud1 siRNA-transfected cells showed decreased Herpud1 protein expression and hypertrophy formation compared to control cells [2]; Overexpression of Herpud1 suppresses Ang II-induced cell hypertrophy; and [3] Overexpression of Herpud1 inhibits nuclear translocation of NFATc4.

Discussion: It was suggested that Herpud1 might be an anti-hypertrophic gene in Ang II induced cardiomyocytes hypertrophy.