OBJECTIVETo investigate the effect of resveratrol (RSV) on angiotensin II (Ang II) induced cardiomyocytes hypertrophy and FoxO1/MnSOD signaling pathway.

METHODSThe cardiomyocytes isolated from neonatal Wistar rats were cultured with pancreatin and preplating technique and divided into five groups: control (CON), Ang II (1 x 10(-6) mol/L, Ang II), Ang II + RSV (10 µmol/L), Ang II + RSV (25 µmol/L), and Ang II + RSV (50 µmol/L). 3H-Leucine incorporation method were used to determine the cardiomyocyte protein synthesis rate. Cell size was measured by phase contrast microscope. The gene expression of A type natriuretic factor (ANF) was detected by real-time PCR. Western blot was used to measure the expression of MnSOD, FoxO1 and acety-FoxO1. Immunoprecipitation was used to detect the interaction between Sirt1 and FoxO1.

RESULTSCardiomyocyte protein synthesis rate in Ang II group was significantly higher in Ang II group than in the control group ((1,971 ± 175) cpm vs. (1,216 ± 136) cpm, P < 0.05), which could be significantly attenuated by RSV (10 µmol/L, 25 µmol/L, 50 µmol/L, all P < 0.05), especially in Ang II + RSV (25 µmol/L) group( (1,374 ± 143) cpm). Cardiomyocytes size in Ang II group was significantly larger than control group ((29.3 ± 3.2) µm vs. (19.4 ± 1.8) µm, P < 0.05), which could be significantly reduced by cotreatment with RSV (10 µmol/L, 25 µmol/L, 50 µmol/L, all P < 0.05), especially in Ang I + RSV (25 µmol/L) group ((20.8 ± 2.1) µm). Ang II also significantly upregulated ANP mRNA expression of cardiomyocytes (4.4 ± 0.4 vs. 1.0 ± 0.1 in control group, P < 0.05), which could be significantly inhibited by cotreatment with RSV, especially in Ang II + RSV (25 µmol/L) group (2.2 ± 0.2). Ang II significantly decreased MnSOD expression of cardiomyocytes compared with control group (P < 0.05), which was reversed by RSV (25 µmol/L). The binding level of Sirt1 and FoxO1 was significantly lower (1.00 ± 0.11 vs. 1.63 ± 0.16, P < 0.05), and the expression of acetylation of FoxO1 was significantly higher in Ang II group than in control group (1.48 ± 0.16 vs. 1.00 ± 0.13, P < 0.05), which was significantly reversed by cotreatment with RSV (25 µmol/L).

CONCLUSIONSResveratrol treatment can inhibit Ang II induced cardiomyocyte hypertrophy. This protective effect is associated with reduced FoxO1 acetylation and activation of Sirt1, suggesting that Sirt1 may serve as a potential therapeutic target of cardiomyocyte hypertrophy.