Protective effects of Sphingosine-1-phosphate (S1P) on hypertrophic response in H9c2 cardiomyocytes

Abstract

To investigate the effects of sphingosine-1-phosphate (S1P) on cardiac hypertrophic response in H9c2 cells. H9c2 cells were randomly divided into four groups: normal control group, S1P (1 μmol/L) treated group, Phenylephrine (PE) (100 μmol/L) treated group, PE (100 μmol/L) treated group combined with S1P (1 μmol/L) treatment. Each group has 3 duplicated wells. After 24 hours, the size of H9c2 cells in each group was detected by Actin-Trakcer Green immunofluorescence staining. Transcriptional levels of hypertrophic markers ( ANP, BNP and β-MHC) in H9c2 cells were determined by real-time PCR. Western blot was performed to examine the expression level of ANP in each group. Then H9c2 cells were randomly divided into five groups: normal control group, PE (100 μmol/L) treated group, PE (100 μmol/L) with S1P low-dose (0.1 μmol/L) treated group, PE (100 μmol/L) with S1P middle-dose (1 μmol/L) treated group and PE (100 μmol/L) with S1P high-dose (10 μmol/L) treated group. Each group has 3 duplicated wells. After 24 hours, Western blot was performed to examine the expressions of phosphorylated Janus kinase 2 (JAK2) and signal transducers and activators of transcription 3 (STAT3) under low, medium and high concentrations of S1P. Each experiment was repeated three times. Compared with normal control group, the surface area of H9c2 cells in PE group was increased significantly (P＜0.05), meanwhile, the transcription levels of ANP, BNP and β-MHC were increased significantly (all P＜0.05), and the expression of ANP was also increased significantly (P＜0.05) in PE group. While compared with PE group, the surface area of H9c2 cells in PE + S1P group was decreased significantly (P＜0.05), the transcription levels of ANP, BNP and β-MHC and the expression of ANP were also decreased significantly (all P＜0.05) in PE + S1P group. After treated with PE and different concentrations of S1P, the expressions of p-JAK2 and p-STAT3 were increased significantly compared with the normal control group and PE group (P＜0.05), in a dose-dependent manner. S1P could protect H9c2 cells against hypertrophic response induced by PE, which may be achieved by activating JAK2/STAT3 signal pathway.