ABSTRACT
Objective: To investigate the inhibitory effect of leonurine on cardiomyocyte hypertrophy induced by angiotensin Ⅱ(Ang Ⅱ) and its effect on p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway and miRNA-1.Method: Cardiomyocyte hypertrophy was induced by Ang Ⅱ (0.1 μmol·L-1) in primary neonatal cardiomyocytes. Experiments were designed in 6 groups as following:normal group, model group, p38 MAPK inhibitor group (SB203580, 10 μmol·L-1), low-dose(5 μmol·L-1), middle-dose(10 μmol·L-1) and high-dose(20 μmol·L-1) group. The cardiomyocyte surface area was measured by image software, and the protein contents were detected by Lowry. The concentrations of ANP in the culture supernatant were measured by enzyme-linked immunosorbent assay (ELISA). The expression level of miRNA-1 was detected by Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR), and the protein expression levels of endothelin-1 (ET-1), p38 MAPK, p-p38 MAPK, myocyte enhancer factor 2 (MEF2), β-myosin heavy chain (β-MHC), α-myosin heavy chain (α-MHC) were detected by Western blot.Result: Compared with normal group, the surface area of cardiomyocyte, the protein contents, the concentrations of ANP, and the protein expression levels of ET-1, p38 MAPK, p-p38 MAPK, MEF2, β-MHC in model group were higher (Pα-MHC and miRNA-1 were lower than those in normal group (Pβ-MHC in high-dose group were lower (Pα-MHC and miRNA-1 were higher than those in model group (PConclusion: Leonurine (20 μmol·L-1) could inhibit cardiomyocyte hypertrophy induced by AngⅡ, and the mechanism is related to the inhibition of activation of p38 MAPK signaling pathway and up-regulation the expression of miRNA-1.