Original Research: Atorvastatin prevents rat cardiomyocyte hypertrophy induced by parathyroid hormone 1–34 associated with the Ras-ERK signaling

Abstract

We investigated the effects of atorvastatin (Ator) on cardiomyocyte hypertrophy (CMH) induced by rat parathyroid hormone 1–34 (PTH1–34) and Ras-extracellular signal regulated protein kinases 1/2 (ERK1/2) signaling. Rat cardiomyocytes were randomly divided into seven groups: normal controls (NC), PTH1–34 (10⁻⁷ mol/L), Ator (10⁻⁵ mol/L), farnesyl transferase inhibitors-276 (FTI-276, 4 × 10⁻⁵ mol/L), PTH1–34 + Ator, PTH1–34 + FTI-276 and PTH1–34 + Ator + mevalonic acid (MVA, 10⁻⁴ mol/L). After treatment, the hypertrophic responses of cardiomyocytes were assessed by measuring cell diameter, detecting protein synthesis, and single-cell protein content. The concentrations of hypertrophic markers such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were measured by ELISA. Protein expressions of ERK1/2, p-ERK1/2 and Ras were detected by western blotting. The results showed that compared with the PTH1–34 group, cellular diameter, 3H-leucine incorporation, single-cell protein content, ANP and BNP concentration decreased by 12.07 µm, 1622 cpm/well, 84.34 pg, 7.13 ng/L and 20.04 µg/L, respectively, and the expressions of Ras and p-ERK1/2 were downregulated in PTH1–34 + Ator group (P < 0.05). Compared to the PTH1–34 + Ator group, the corresponding hypertrophic responses and hypertrophic markers increased by 4.95 µm, 750 cpm/well, 49.08 pg, 3.12 ng/L and 9.35 µg/L, respectively, and the expressions of Ras and p-ERK1/2 were upregulated in the PTH1–34 + Ator + MVA group (P < 0.05). In conclusion, Ator prevents neonatal rat CMH induced by PTH1–34 and Ras-ERK signaling may be involved in this process.