RNAi-Mediated Down-Regulation of CD47 Protects against Ischemia/Reperfusion-Induced Myocardial Damage via Activation of eNOS in a Rat Model

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Ischemia-reperfusion injury is associated with serious clinical manifestations, including myocardial hibernation, acute heart failure, cerebral dysfunction, gastrointestinal dysfunction, systemic inflammatory response syndrome, and multiple organ dysfunction syndrome. Ischemia-reperfusion injury is a critical medical condition that poses an important therapeutic challenge for physicians. In this review article, we present recent advances focusing on the basic pathophysiology of ischemia-reperfusion injury, especially the involvement of reactive oxygen species and cell death pathways. The involvement of the NADPH oxidase system, nitric oxide synthase system, and xanthine oxidase system are also described. When the blood supply is re-established after prolonged ischemia, local inflammation and ROS production increase, leading to secondary injury. Cell damage induced by prolonged ischemia-reperfusion injury may lead to apoptosis, autophagy, necrosis, and necroptosis. We highlight the latest mechanistic insights into reperfusion-injury-induced cell death via these different processes. The interlinked signaling pathways of cell death could offer new targets for therapeutic approaches. Treatment approaches for ischemia-reperfusion injury are also reviewed. We believe that understanding the pathophysiology ischemia-reperfusion injury will enable the development of novel treatment interventions.

Section: Mechanism Of Ischemia-reperfusion Injurymentioning

confidence: 99%

Current Mechanistic Concepts in Ischemia and Reperfusion Injury

Yiang

Liao

et al. 2018

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728

“…However, restoration of the blood flow can induce even worse microstructural destruction, termed myocardial ischemia/reperfusion injury (MIRI), which lessens the beneficial effect of reperfusion therapy [1]. Recently, a series of in vitro and in vivo studies have demonstrated that innate inflammation, apoptosis, autophagy, platelet activation, and oxidative stress contribute to MIRI [2][3][4][5][6]. However, there is no effective strategy for limiting or preventing MIRI, so a new molecular therapeutic target is necessary.…”

Section: Introductionmentioning

confidence: 99%

Down-Regulation of miR-327 Alleviates Ischemia/Reperfusion-Induced Myocardial Damage by Targeting RP105

Yang

Liu

et al. 2018

Self Cite

Background/Aims: Micro RNAs (miRNAs) play a very important role in myocardial ischemia/ reperfusion injury (MIRI), including in inflammation, apoptosis, and angiogenesis. Previous studies have demonstrated up-regulation of miR-327 in renal ischemia/reperfusion injury and MIRI. Via TargetScan, we found RP105 is a possible target gene of miR-327; our previous studies have also confirmed that RP105 acted as a cardioprotective protein in MIRI by reducing inflammation. However, the regulatory effect of miR-327 on RP105 has not previously been proposed. In our study, we aimed to identify the regulatory effect of miR-327 on RP105 protein in MIRI rats. Methods: Sixty male Sprague–Dawley rats were randomly divided into five groups, which were pre-treated with saline (sham and ischemia/reperfusion group), adenovirus-expressing miR-327-RNAi (Ad-miR-327-i group), control (Ad-NC group), or pri-miR-327 (Ad-miR-327 group) treatments. Three days later, the rat MIRI model was established by ischemia for 30 min, followed by reperfusion for 3 h. Myocardium and plasma were harvested and assessed. Results: miR-327 was increased by nearly 3-fold both in myocardium and plasma, which down-regulated RP105 in a 3′-untranslated region-dependent manner, and down-regulation of miR-327 via adenovirus transfection indirectly suppressed the TLR4/ TLR2-MyD88-NF-κB signaling axis activation via up-regulation of RP105, which subsequently resulted in reduced myocardial infarct size, attenuated cardiomyocyte destruction, and alleviated inflammation. In contrast, up-regulation of miR-327 induced the opposite effect. Conclusion: Down-regulation of miR-327 exerts a cardioprotective effect against MIRI by reducing inflammation, which may constitute a promising molecular therapeutic target for treating MIRI.

“…The activated Akt pathway can regulate cell survival through phosphorylation of a variety of downstream targets, such as pro-apoptotic protein, transcription factors and endothelial nitric oxide synthase (eNOS) [7-9]. The activation of the PI3K/Akt pathway protects the brain from cerebral I/R injury by preventing neuronal apoptosis [10].…”

Section: Introductionmentioning

confidence: 99%

Troxerutin Protects Against Myocardial Ischemia/Reperfusion Injury Via Pi3k/Akt Pathway in Rats

Shu

Zhang

Huang

et al. 2017

Background/Aims: Troxerutin, also known as vitamin P4, has been commonly used in the treatment of chronic venous insufficiency (CVI) disease. However, its effect on in vivo myocardial ischemia/reperfusion (I/R) injury, a model that closely mimics acute myocardial infarction in humans, is still unknown. Methods: The myocardial I/R injury rat model was created with troxerutin preconditioning. Myocardial infarct size was evaluated by the Evans blue-TTC method. Hemodynamic parameters, including the heart rate (HR), left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), maximal rate of rise in blood pressure in the ventricular chamber (+dp/dt max), and maximal rate of decline in blood pressure in the ventricular chamber (-dp/dt max) were monitored. Serum TNF-α and IL-10 were determined by ELISA kit. Cell apoptosis was detected by MTT method. Results: Troxerutin preconditioning significantly reduced myocardial infarct size, improved cardiac function, and decreased the levels of creatine kinase (CK), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in the I/R injury rat model. The serum and mRNA levels of TNF-α and IL-10 as well as some apoptosis markers (Bax, Caspase 3) also decreased. Moreover, troxerutin pretreatment markedly increased the phosphorylation of Akt, and blocking PI3K activity by LY294002 abolished the protective effect of troxerutin on I/R injury. Conclusion: Troxerutin preconditioning protected against myocardial I/R injury via the PI3K/Akt pathway.