RESUMO
Schizandrin B exhibits prominent antioxidant and anti-inflammatory effects, and plays an important role in ameliorating myocardial ischemia/reperfusion injury. However, the underlying protective mechanisms remain to be elucidated. The aim of the present study was to explore the cardioprotective effects of schizandrin B against hypoxia/reoxygenation (H/R)-induced H9c2 cell injury, focusing on the role of the adenosine monophosphate-activated protein kinase (AMPK)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in this process. The results showed that schizandrin B attenuated the H/R-induced decrease in cell viability and the increase in lactate dehydrogenase release, as well as the apoptosis rate in H9c2 cells. Schizandrin B also mitigated H/R-induced oxidative stress, as illustrated by the decrease in intracellular reactive oxygen species generation, malondialdehyde content and NADPH oxidase 2 expression, and the increase in antioxidant enzyme superoxide dismutase and glutathione peroxidase activities. In addition, schizandrin B reversed the H/R-induced upregulation of pro-inflammatory cytokines [interleukin (IL)-1ß (IL-1ß) tumor necrosis factor-α, IL-6 and IL-8] and the downregulation of anti-inflammatory cytokines (transforming growth factor-ß and IL-10) in the culture supernatant. Notably, schizandrin B increased the expression of Nrf2, NAD(P)H: Quinone oxidoreductase (NQO-1) and heme oxygenase-1 (HO-1) in H/R-treated H9c2 cells, activating the Nrf2 signaling pathway. The cardioprotection of schizandrin B against H/R injury was inhibited by Nrf2 knockdown induced byNrf-2-specific small interfering RNA (siRNA; si-Nrf2) transfection. Furthermore, schizandrin B enhanced phosphorylated (p)-AMPK expression, while AMPK knockdown induced by AMPK-specific siRNA(si-AMPK) transfection remarkably eliminated schizandrin B-induced cardioprotection and reduced Nrf2 expression in H/R-treated H9c2 cells. Taken together, these results suggested that schizandrin B exerts cardioprotection on H/R injury in H9c2 cells due to its antioxidant and anti-inflammatory activities via activation of the AMPK/Nrf2 pathway.
RESUMO
OBJECTIVE: ST-Segment Elevation Myocardial Infarction (STEMI) patients with the multivessel disease have distinctive plaque characteristics in non-IRA lesions. Intensive statin therapy was a potential approach to treat STEMI patients with the non-IRA disease. However, there is still poor evidence about the therapeutic effect. In this study, we have evaluated the detailed therapeutic effect of statin plus ezetimibe intensive therapy. METHODS: For STEMI patients with non-IRA disease undergoing primary Percutaneous Coronary Intervention (PCI), 183 control STEMI patients without non-IRA disease undergoing primary PCI, and 200 STEMI patients with non-IRA disease undergoing primary PCI were introduced into this study. 200 STEMI patients with non-IRA disease undergoing primary PCI were divided into Normal group, Intensive group, Normal & Combined group, and Intensive & Combined group. The baseline information for each participant was recorded. Meanwhile, the physiological and biochemical indicators of each member with different treatments were collected after one-year follow-up. RESULTS: For STEMI patients with non-IRA disease undergoing primary PCI, no differences could be detected in multiple indexes such as OCT examination results, age, stroke, etc. However, diabetes mellitus, smoking, and coronary Gensini score were different between different groups (P<0.05). After one year follow-up, cholesterol, low-density lipoprotein, coronary Gensini score, thin-cap fibroatheroma, length of non-infarcted arterial lesions, non-infarct artery lesion range, myocardial infarction again, and revascularization again were significantly different between different groups (P<0.05). CONCLUSION: The results mentioned above suggested that pitavastatin combined with ezetimibe was an effective approach for STEMI patients with non-IRA disease undergoing primary PCI. The results obtained in this study have provided a novel method for the treatment of STEMI patients with non-IRA disease undergoing primary PCI.