Follistatin-like 1 Protects Cardiomyoblasts From Injury Induced By Lipopolysaccharides Through Modulating PI3K/Akt Signaling

Objective: Sepsis is generally viewed as a disease aggravated by an inappropriate immune response encountered in the afflicted individual.As an important organ system frequently compromised by sepsis and always affected by septic shock,the cardiovascular system is more likely to be affected.Studies have shown that cardiac dysfunction is associated with cardiomyocyte apoptosis,and sepsis has a great relationship with Lipopolysaccharide(LPS),An increasing number of studies have confirmed that FSTL1 can reduce cardiomyocyte apoptosis induced by various factors,however,it is still not clear whether FSTL1 can attenuate the LPS-induced cardiomyocyte apoptosis.In order to investigate the effect of FSTL1 on cardiomyocyte apoptosis induced by LPS and its mechanism,we designed this experiment.Methods: In vitro,the rat fetal ventricu Lar cardiomyocytes(H9C2)were used for experiments.1,LPS-induced H9C2 cell apoptosis was induced by LPS(2uM)for 48 hours;2,H9C2 cells were pretreated with exogenous recombinant FSTL1 protein(100ng / m L)for 30 min before stimulation with LPS,DAPI and TUNEL staining to determine whether FSTL1 can reduce LPS-induced apoptosis of H9C2 cells;3,silencing FSTL1 gene by transfection of si FSTL1,whether to increase LPS-induced apoptosis of H9C2 cells;4,through the detection of reactive oxygen species(ROS)to explore the mechanism of LPS-induced apoptosis of H9C2 cells,and the introduction of FSTL1 to explore the mechanism of its protective effect;5,by introducing PI3K/Akt inhibitor,LY294002,further study the mechanism of FSTL1 protects H9C2.Results: 1,H9C2 cells were successfully cultured and established LPS-induced apoptosis model of H9C2 cells.DAPI and TUNEL staining showed that H9C2 cells stimulated by LPS for 48 hours,compared with H9C2 cells without LPS stimulation,,the number of apoptosis of H9C2 cells increased significantly.2,H9C2 cells were pretreated with exogenous FSTL1 protein(100ng / m L)for 30 min before stimulation with LPS,DAPI and TUNEL staining showed that H9C2 cells stimulated with LPS after pretreatment with recombinant FSTL1 for 30 min,compared with those without FSTL1 pretreatment,cardiomyocyte apoptosis was significantly reduced;3,by transfection of siFSTL1 silencing endogenous FSTL1 gene expression,and then Stimulating H9C2 cells with LPS,DAPI and TUNEL staining showed that,compared with non-silent endogenous FSTL1 gene expression in H9C2 cells,Silence of the endogenous FSTL1 gene expression in H9C2 cells significantly increased the number of apoptotic cells;4,stimulation of H9C2 cells 48 hours by LPS,can increase the production of ROS,however,introduction of exogenous recombinant FSTL1 inhibits LPS-induced H9C2 cells to produce ROS;5,after the introduction of LY294002 interference Akt signal pathway,DAPI and TUNEL staining showed that the protection of FSTL1 on LPS-induced apoptosis of H9C2 cells was significantly attenuated,and exogenous recombinant FSTL1 no longer inhibits LPS-induced H9C2 cells to produce ROS.Conclusion: LPS can induce H9C2 cell apoptosis,and FSTL1 can attenuate LPS-induced apoptosis of H9C2 cells;LPS may induce H9C2 cell apoptosis by inducing H9C2 cells to produce ROS,and FSTL1 inhibits LPS-induced H9C2 cells to produce ROS,The protective effect of FSTL1 on H9C2 cells is achieved at least by activating the PI3K/Akt signaling pathway.