Effect of imatinib on DOCA-induced myocardial fibrosis in rats through P38 MAPK signaling pathway
EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES
Authors: Dong, B.; Chen, D-F; Bu, X-H; Qin, H-B; Xi, Y.
Abstract
OBJECTIVE: To explore the role of imatinib in desoxycorticosterone acetate (DO-CA)-induced myocardial fibrosis in rats by the p38 mitogen-activated protein kinase (MAPK) signaling pathway. MATERIALS AND METHODS: Normal group (n=20), DOCA induction group (n=20), and imatinib treatment group (treatment group, n=20) were set up. Then, the cardiac function was examined via magnetic resonance imaging (MRI) and echocardiography (ECG) on the 21st d after modeling. Alkaline phosphatase (ALP) and myocardial function index creatine kinase-MB (CK-MB) were detected. The enzyme-linked immunosorbent assay (ELISA) was performed to measure tumor necrosis factor-gamma (TNF-gamma) and interleukin-6 (IL-6). Hematoxylin-eosin (HE) staining assay was carried out to observe the pathological changes in myocardial tissues. Quantitative Polymerase Chain Reaction (qPCR) and Western blotting were employed to measure the expression levels of important myocardial fibrosis-related genes [checkpoint kinase 1 (Chek1) and alpha-smooth muscle actin (a-SMA)], as well as genes and proteins of the p38 MAPK signaling pathway. RESULTS: In comparison with the normal group. DOCA induction group had significantly lowered fractional shortening (FS. %) and ejection fraction (EF, %), but overtly increased left ventricular end-diastolic dimension (LVEDd) and left ventricular end-systolic dimension (LVESd), as well as levels of serum ALP, alanine aminotransferase (ALT), and CKMB. Besides, the levels of TNF-gamma, IL-6, and IL-1 beta were notably raised in the DOCA induction group. HE staining results showed that myocardial injury was more severe in DOCA induction group. The results of the gene detection revealed that the expression levels of Chek1. alpha-SMA. p38 MAPK. and JNK were evidently higher in DOCA induction group than those in the imatinib treatment group (p<0.05), and the expression of p38 MAPK protein in the rat myocardial tissues was remarkably lower in the treatment group than that in the DOCA induction group (p<0.05). CONCLUSIONS: Imatinib can regulate the repair of myocardial injury caused by DOCA-induced myocardial fibrosis in rats by repressing the p38 MAPK signaling pathway.
The Anti-inflammatory Mediator Resolvin E1 Protects Mice Against Lipopolysaccharide-Induced Heart Injury
FRONTIERS IN PHARMACOLOGY
Authors: Zhang, Jishou; Wang, Menglong; Ye, Jing; Liu, Jianfang; Xu, Yao; Wang, Zhen; Ye, Di; Zhao, Mengmeng; Wan, Jun
Abstract
Background Sepsis-induced cardiomyopathy (SIC) is a common severe complication of sepsis that contributes to mortality. SIC is closely associated with excessive inflammatory responses, failed inflammation resolution, and apoptotic damage. Resolvin E1 (RvE1), an omega-3 polyunsaturated fatty acid (PUFA)-derived metabolite, has been reported to exert anti-inflammatory or proresolving activity in multiple animal models of inflammatory disease. However, the therapeutic potential of RvE1 in SIC remains undetermined, which was, therefore, the aim of the present study. Methods C57BL/6J mice were randomly divided into three groups: control, lipopolysaccharide (LPS), and LPS + RvE1. Echocardiography, Western blotting (WB), quantitative real-time (QRT)-PCR, histological analyses, and flow cytometry were used to evaluate cardiac function, myocardial inflammation, and the underlying mechanisms. Results The RvE1-injected group showed improved left ventricular (LV) function and reduced serum lactate dehydrogenase (LDH) and creatine kinase myocardial bound (CK-MB) levels. Compared to LPS treatment alone, RvE1 treatment inhibited the infiltration of neutrophils and macrophages into the heart and spleen and suppressed the secretion of pro-inflammatory cytokines, including interleukin (IL)-1 beta, IL-6, and monocyte chemoattractant protein (MCP)-1, in the heart. We also observed that the activation of the mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappa B signaling pathways was blocked by RvE1 treatment, and this inhibition contributed to the improvement in the inflammatory response induced by LPS. RvE1 inhibited LPS-induced M1 macrophage polarization and promoted macrophage polarization toward the M2-like phenotype in both the heart and spleen. In addition, LPS administration dysregulated cyclooxygenase (COX) and lipoxygenase (LOX) in the heart, which were rectified by RvE1 treatment. RvE1 also reduced myocardial apoptosis rate in response to LPS-induced heart injury. Conclusion RvE1 protects the heart against SIC possibly through the inhibition of the MAPK and NF-kappa B inflammatory signaling pathways, modulation of macrophage polarization, and reduction in myocardial apoptosis. RvE1 may be a novel lipid mediator for the treatment of SIC.