Mechanisms of the BMP4/ERK1/2 signaling pathway mediating H9C2 myocyte hypertrophy in rats
10.16571/j.cnki.1008-8199.2016.02.008
- VernacularTitle:骨形成蛋白4通过激活 ERK1／2信号通路诱导大鼠H9 C2心肌细胞肥大的机制
- Author:
Yezhen TAO
;
Huaxu LI
;
Yu YUAN
- Publication Type:Journal Article
- Keywords:
Myocardial cells;
H9C2;
Hypertrophy;
Extracellular signal regulating kinase;
Signaling pathway;
Bone morpho-genetic protein 4
- From:
Journal of Medical Postgraduates
2016;(2):153-158
- CountryChina
- Language:Chinese
-
Abstract:
Objective The stimulating factors and etiology of myocyte hypertrophy are not yet clear.We aim to investigate the mechanisms of bone morphogenetic protein 4 (BMP4)-induced H9C2 myocyte hypertrophy in rats by activating the extracellular signal regulating kinase ( ERK1/2) signaling pathway. Methods Rat H9C2 myocytes were cultured, the model of BMP4-induced H9C2 myocyte hypertrophy was established, and the cells were randomly di-vided into control A, BMP4 A, and angiotensinⅡ( AngⅡ) groups to be treated for 48 hours.The changes in the expression of ERK1/2 protein phosphorylation were observed at 0, 10, 30, 60, and 120 min after treated with BMP4 at the concentration of 50 μg/L and at 30 min after treated with BMP4 at 0, 10, 50, and 100 μg/L.The changes of the H9C2 myocytes were also observed after blocking the ERK1/2 signaling pathway.The cells were divided into control B, BMP4 B, BMP4+PD98059, and PD98059 groups to be cultured with 50μg/L BMP4 for another 48 hours after 30 min blockage with PD98059 at 50 ×10 -6 mol/L.The size and area of the cells were measured by inverted microscopy and image J Software, their total protein content detected by BCA, and the expressions of p-ERK1/2 and brain natriuretic peptide ( BNP) determined by Western blot. Results Compared with control A, the BMP4 A, and AngⅡ groups showed markedly larger cell areas ([649.74 ±2.03] vs [744.85 ±1.31] and [748.39 ±1.54] μm2), higher protein contents ([243.18 ±3.69] vs [340.09 ±2.14] and [347.43 ± 3.30] pg/cell), and higher expressions of the BNP protein ([0.72 ±0.44] vs [0.96 ±0.55] and [1.07 ±0.55]/GAPDH), with statistically significant differences between any two groups (P>0.05).After BMP4 intervention, the expression of p-ERK1/2 manifes-ted a time-dependent trend of first going up and then coming down, reaching the peak at 30 min, with the ERK1/2 protein phosphoryl-ation significantly higher at 30 min than at 10 min (P>0.05), especially than at 0, 60, and 120 min (P>0.01).The level of p-ERK1/2 protein phosphorylation in the mytocytes was elevated with the increased concentration of BMP4, remarkably higher at 50μg/L than at 0 and 10μg/L, but lower than at 100μg/L ( P>0.01) .The cell area, protein content, and BNP protein expression of the H9C2 myocytes were significantly lower in the BMP4+PD98059 group ([650.49 ±1.28] μm2, [244.06 ±3.48] pg/cell, and [0.55 ±0.15]/GAPDH) than in the BMP4 B group ([746.04 ±1.45] μm2, [343.57 ±4.11] pg/cell, and [0.79 ±0.55]/GAPDH) (P>0.01). Conclusion BMP4 may induce hypertrophy of rat H9C2 myocytes by activating the ERK1/2 signaling path-way.Early blocking of ERK1/2 activation may contribute to the management of myocardial hypertrophy.
