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Objective. To investigate the effect of CA on autophagy and its molecular mechanism after myocardial ischemia/reperfusion injury (MI/RI). Methods. The MI/RI model was established by the ligation of the left anterior descending coronary artery with ischemia and reperfusion. In vitro cell models were established using hypoxia/reoxygenation. Western blot was used to determine the expression levels of beclin-1, P62, and LC3 II. The expression levels of IL-1β, IL-6, TNFα, and apoptosis-related genes Bax, Cyt-c, and Bcl-2 were detected by qRT-PCR. Cell activity was detected by CCK-8. Apoptosis was detected by TUNEL staining. Results. Beclin-1, P62, and LC3 II protein expression and LC3 II/LC3 I level were significantly increased after myocardial ischemia-reperfusion injury. Compared with model group, CA downregulated beclin-1, P62, and LC3 II protein expression and LC3 II/LC3 I level in the myocardium. The results of cell-level experiments showed that CA inhibited the autophagy response of the cardiomyocytes induced by hypoxia-reperfusion injury. Mechanism studies showed that CA targeted the inhibition of ATG12. Knocking down ATG12 reduces the production of inflammatory cytokines induced by H/R. The knockdown of ATG12 also reduced apoptosis and injury of the myocardial cells. Conclusion. Myocardial ischemia-reperfusion can enhance autophagy response and promote apoptosis. CA plays a protective role in myocardium by targeting ATG12, thereby inhibiting autophagy and improving myocardial cell apoptosis. [ABSTRACT FROM AUTHOR]

The inhibitory effect of muscone on the hyperinflammatory response after myocardial ischemia reperfusion injury (MIRI) was investigated, and the target and signal pathways of muscone were explored. The levels of inflammatory cytokines interleukin-1β, interleukin-6, and tumor necrosis factor alpha were detected through qRT-PCR and ELISA. The expression levels of p38 and NF-κB signaling pathway-related proteins were detected through Western blot. TREM-1 siRNA was transfected into macrophages in vitro. The rat model of myocardial ischemia was established and used in studying the inhibitory effect of muscone on the inflammatory response and its protective effect muscone on myocardial apoptosis. The expression of TREM-1 was upregulated during myocardial ischemia. Knocking down TREM-1 decreased the increase in inflammatory cytokines in the supernatant of macrophages induced by rmHMGB1 (1 μg/mL) and rmHSP60 (1 mol/mL). In addition, knocking down TREM-1 decreased p38 and NF-κB signaling activation. Muscone can protect myocardial cells by inhibiting the expression of TREM-1 and the inflammatory response after myocardial infarction. Further study showed that muscone inhibited the production of DAM-triggered (damage-associated molecular pattern trigger) inflammatory cytokines. In addition, muscone inhibited the activation of p38 and NF-κB signals under DAM-induced conditions. Muscone and TREM-1 gene knockout reduced cell apoptosis and provided protection against MIRI by inhibiting p38 and NF-κB signaling activation. Mechanism studies showed that muscone inhibited the production and release of inflammatory cytokines by inhibiting TREM-1, and thereby reducing the inflammatory response and providing protection against MIRI. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of Ginkgolide B (GB) on doxorubicin (DOX) induced cardiotoxicity in vitro and in vivo. Rat cardiomyocyte cell line H9c2 was pretreated with GB and subsequently subjected to doxorubicin treatment. Cell viability and cell apoptosis were assessed by MTT assay and Hoechst staining, respectively. Reactive oxygen species (ROS), Akt phosphorylation and intracellular calcium were equally determined in order to explore the underlying molecular mechanism. To verify the in vivo therapeutic effect of GB, we established a mouse model of cardiotoxicity and determined left ventricle ejection fraction (LVEF) and left ventricular mass (LVM). The in vitro experimental results indicated that pretreatment with GB significantly decreases the viability and apoptosis of H9c2 cells by decreasing ROS and intracellular calcium levels and activating Akt phosphorylation. In the in vivo study, we recorded an improved LVEF and a decreased LVM in the group of cardiotoxic rats treated with GB. Altogether, our findings anticipate that GB exerts a cardioprotective effect through possible regulation of the ROS, Akt and calcium pathways. The findings suggest that combination of GB with DOX in chemotherapy could help avoid the cardiotoxic side effects of GB. [ABSTRACT FROM AUTHOR]