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21.
《Free radical research》2013,47(3-6):169-180
Numerous studies have indirectly, suggested that oxygen-derived free radicals play an important path-ogenetic role in the prolonged depression of contractile function observed in myocardium reperfused after reversible ischemia (myocardial “stunning”). In order to provide direct evidence for the oxy-radical hypothesis of stunning, we administered the spin trap, α-phenyl N-tert-butyl nitrone (PBN), to open-chest dogs undergoing a 15-min coronary artery occlusion followed by reperfusion. Plasma of local coronary venous blood was analyzed by electron paramagnetic resonance (EPR) spectroscopy. EPR signals characteristic of radical adducts of PBN appeared during ischemia and increased dramatically in the first few minutes after reperfusion. After this initial burst, the production of adducts abated but did not cease, persisting up to 3 h after reflow. The production of PBN adducts after reperfusion was inversely related to collateral flow during ischemia. PBN itself enhanced recovery of contractile function. indicating that the radicals trapped may play a pathogenetic role in myocardial stunning. Superoxide dismutase plus catalase attenuated PBN adduct production and, at the same time, improved recovery of contractile function. Antioxidant therapy given 1 min before reperfusion suppressed PBN adduct production and improved contractile recovery; however, the same therapy given 1 min after reperfusion did not suppress early radical production and did not attenuate contractile dysfunction. After i.v. administration, the elimination half-life of PBN was estimated to be approximately 4–5 h. The results demonstrate that 1) free radicals are produced in the stunned myocardium in intact animals; 2) inhibition of free radical production results in improved contractile recovery; and 3) the free radicals important in causing dysfunction are produced in the first few minutes of reperfusion. Taken together, these studies provide cogent evidence supporting the oxy-radical hypothesis of stunning in open-chest dogs. It is now critical to determine whether these results can be reproduced in conscious animal preparations. 相似文献
22.
《Biomarkers》2013,18(4):304-309
AbstractObjective: The aim was to assess serial measurements of high-sensitivity cardiac troponin T (hs-cTNT) post-exercise in patients with stable coronary artery disease (CAD).Methods: Twelve patients with positive coronary angiograms (CAD positives) and 12 controls performed an exercise stress test.Results: CAD positive had higher baseline and peak concentrations of hs-cTNT than controls. Significant increases in hs-cTNT were seen in both groups after exercise. In two-third of patients the peak in hs-cTNT was above the 99th percentile.Conclusion: hs-cTNT is higher in patients with stable coronary disease than in controls and exceeds the diagnostic cut-off value for myocardial infarction in a majority of patients with CAD after exercise. 相似文献
23.
Zheyong Huang Yunli Shen Hongmin Zhu Jianfeng Xu Yanan Song Xinying Hu Zhang Shuning Xiangdong Yang Aijun Sun Juying Qian Junbo Ge 《Experimental Animals》2013,62(3):197-203
Cell delivery via the retrograde coronary route boasts less vessel embolism, myocardial
injury, and arrhythmogenicity when compared with those via antegrade coronary
administration or myocardial injection. However, conventional insertion into the coronary
sinus and consequent bleeding complication prevent its application in small animals. To
overcome the complication of bleeding, we described a modified coronary retroinfusion
technique via the jugular vein route in rats with myocardial infarction (MI). A flexible
wire with a bent end was inserted into the left internal jugular vein and advanced slowly
along the left superior vena cava. Under direct vision, the wire was run into the left
cardiac vein by rotating the wire and changing the position of its tip. A fine tube was
then advanced along the wire to the left cardiac vein. This modified technique showed less
lethal hemorrhage than the conventional technique. Retroinfusion via transjugular catheter
enabled efficient fluid or cell dissemination to the majority areas of the free wall of
the left ventricle, covering the infarcted anterior wall. In conclusion, transjugular
cardiac vein catheterization may make retrocoronary infusion a more safe and practical
route for delivering cell, drug, and gene therapy into the infarcted myocardium of
rats. 相似文献
24.
《Biomarkers》2013,18(5):441-446
Context: Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play divergent roles in myocardial ischemia and reperfusion injury.Objective: To investigate serum Ang-1 and Ang-2 levels in ST-segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (PCI).Methods: Serum Ang-1 and Ang-2 were measured in 85 STEMI patients in the first week after PCI.Results: Ang-1, Ang-2 and Ang-2/Ang-1 ratio (Ang-2/1) were all increased at admission, and had dynamic changes after PCI. Ang-2 and Ang-2/1 at admission and 2 h after PCI were positively correlated with peak cardiac troponin T levels.Conclusion: The extent of myocardial damage may be linked to circulating Ang-2 and Ang-2/1. 相似文献
25.
Ren‐Hua Chen Yi‐Gang Li Kun‐Li Jiao Peng‐Pai Zhang Yu Sun Li‐Ping Zhang Xiang‐Fei Fong Wei Li Yi Yu 《Journal of cellular and molecular medicine》2013,17(5):608-616
The expression of the chemorepellent Sema3a is inversely related to sympathetic innervation. We investigated whether overexpression of Sema3a in the myocardial infarction (MI) border zone could attenuate sympathetic hyper‐innervation and decrease the vulnerability to malignant ventricular tachyarrhythmia (VT) in rats. Survived MI rats were randomized to phosphate buffered saline (PBS, n = 12); mock lentivirus (MLV, n = 13) and lentivirus‐mediated overexpression of Sema3a (SLV, n = 13) groups. Sham‐operated rats served as control group (CON, n = 20). Cardiac function and electrophysiological study (PES) were performed at 1 week later. Blood and tissue samples were collected for histological analysis, epinephrine (EPI), growth‐associated factor 43 (GAP43) and tyrosine hydroxylase (TH) measurements. QTc intervals were significantly shorter in SLV group than in PBS and MLV groups (168.6 ± 7.8 vs. 178.1 ± 9.5 and 180.9 ± 8.2 ms, all P < 0.01). Inducibility of VT by PES was significantly lower in the SLV group [30.8% (4/13)] than in PBS [66.7% (8/12)] and MLV [61.5% (8/13)] groups (P < 0.05). mRNA and protein expressions of Sema3a were significantly higher and the protein expression of GAP43 and TH was significantly lower at 7 days after transduction in SLV group compared with PBS, MLV and CON groups. Myocardial EPI in the border zone was also significantly lower in SLV group than in PBS and MLV group (8.73 ± 1.30 vs. 11.94 ± 1.71 and 12.24 ± 1.54 μg/g protein, P < 0.001). Overexpression of Sema3a in MI border zone could reduce the inducibility of ventricular arrhythmias by reducing sympathetic hyper‐reinnervation after infarction. 相似文献
26.
目的:探讨对急性心梗患者行不同途径急诊经皮冠状动脉治疗(PCi)的临床疗效及预后。方法:选取我院自2011年1月至2012年12月收治的75例sT段抬高的急性心肌梗死患者作为研究对象进行回顾性调查,对比分析经桡动脉PCI(TRA—Pet)和经股动脉PCI(TFA—PCI)两组治疗疗效及出现并发症情况,包括比较两组穿刺成功率,手术时间,术中出血及术后局部及其他并发症等方面,并作统计分析,取P〈0.05为有统计学意义。结果:两组穿刺成功率及PCI手术成功率差异无统计学意义,P〉0.05。在手术操作时间上,TFA—PCI组明显长于TRA—PCI组,差异有统计学意义,P〈0.05。TFA.PCI组局部并发症发生率为11.8%.远期并发症为2.9%。TRA-PCI组局部并发症发生率为2.4%,远期并发症为7.3%,两组差别显著,P〈0.05。结论:TRA—PCI和TFA—PCI在手术时间及术后并发症上有差异,TRA—PCI术中花时间较少,术后局部并发症要轻,值得在临床上推广,但是由于有远期并发症的危险,故术后应加强肝肾功能等的监测。 相似文献
27.
Sara Zalghout Abdullah Kaplan Emna Abidi Ghewa A. El-Achkar Wared Nour-Eldine Asmaa A. Khalil Firas Kobeissy Ahmad Husari Aida Habib Fouad A. Zouein Eva Hamade 《Journal of cellular physiology》2020,235(2):1568-1575
Despite increased social awareness, marketing restraints, tobacco taxation, and available smoking cessation rehab programs, active and passive smoking remain a worldwide challenging epidemic and a key risk factor for cardiovascular diseases development. Although cardiovascular (CV) protection is more pronounced in women than in men due to estrogenic effects, tobacco cigarette smoking exposure seems to alter this protection by modulating estrogen actions via undefined mechanisms. Premenopausal cigarette smoking women are at higher risk of adverse CV effects than non-smokers. In this study, we investigated the impact of cigarette smoking on early CV injury after myocardial infarction (MI) in non-menopausal female mice. Aortic arch calcification, fibrosis, reactive oxygen species, and gene expression of inflammatory and calcification genes were exaggerated in mice exposed to cigarette smoke (CS). These findings suggest that aortic injury following MI, characterized by vascular smooth muscle cells transdifferentiation, calcification, inflammation, and collagen deposition but not cardiac dysfunction is exacerbated with CS exposure. The novel findings of this study highlight the importance of aortic injury on short and long-term prognosis in CS-exposed MI females. Linking those findings to estrogen alteration is probable and entails investigation. 相似文献
28.
Liwen Liang Huili Li Ting Cao Lina Qu Lulu Zhang Guo-Chang Fan Peter A. Greer Jianmin Li Douglas L. Jones Tianqing Peng 《The Journal of biological chemistry》2020,295(49):16840
The human cardiovascular system has adapted to function optimally in Earth''s 1G gravity, and microgravity conditions cause myocardial abnormalities, including atrophy and dysfunction. However, the underlying mechanisms linking microgravity and cardiac anomalies are incompletely understood. In this study, we investigated whether and how calpain activation promotes myocardial abnormalities under simulated microgravity conditions. Simulated microgravity was induced by tail suspension in mice with cardiomyocyte-specific deletion of Capns1, which disrupts activity and stability of calpain-1 and calpain-2, and their WT littermates. Tail suspension time-dependently reduced cardiomyocyte size, heart weight, and myocardial function in WT mice, and these changes were accompanied by calpain activation, NADPH oxidase activation, and oxidative stress in heart tissues. The effects of tail suspension were attenuated by deletion of Capns1. Notably, the protective effects of Capns1 deletion were associated with the prevention of phosphorylation of Ser-345 on p47phox and attenuation of ERK1/2 and p38 activation in hearts of tail-suspended mice. Using a rotary cell culture system, we simulated microgravity in cultured neonatal mouse cardiomyocytes and observed decreased total protein/DNA ratio and induced calpain activation, phosphorylation of Ser-345 on p47phox, and activation of ERK1/2 and p38, all of which were prevented by calpain inhibitor-III. Furthermore, inhibition of ERK1/2 or p38 attenuated phosphorylation of Ser-345 on p47phox in cardiomyocytes under simulated microgravity. This study demonstrates for the first time that calpain promotes NADPH oxidase activation and myocardial abnormalities under microgravity by facilitating p47phox phosphorylation via ERK1/2 and p38 pathways. Thus, calpain inhibition may be an effective therapeutic approach to reduce microgravity-induced myocardial abnormalities. 相似文献
29.
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are the major enzymes responsible for alcohol metabolism in humans. Emerging evidences have shown that functional polymorphisms in ADH and ALDH genes might play a critical role in increasing coronary artery disease (CAD) and myocardial infarction (MI) risks; however, individually published studies showed inconclusive results. The aim of this meta-analysis is to evaluate the associations between the genetic polymorphisms of ADH and ALDH genes with susceptibility to CAD and MI. A literature search was conducted on PubMed, Embase, Web of Science and Chinese BioMedical databases from inception through December 1st, 2012. Crude relative risks (RRs) with 95% confidence intervals (CIs) were calculated. Twelve case–control studies were included with a total of 9616 subjects, including 2053 CAD patients, 1436 MI patients, and 6127 healthy controls. Meta-analysis showed that mutant genotypes (GA + AA) of the rs671 polymorphism in the ALDH2 gene were associated with increased risk of both CAD and MI (CAD: RR = 1.20, 95%CI: 1.03–1.40, P = 0.021; MI: RR = 1.32, 95%CI: 1.11–1.57, P = 0.002). However, there were no significant associations of ADH genetic polymorphisms to CAD and MI risks (CAD: RR = 0.92, 95%CI: 0.73–1.15, P = 0.445; MI: RR = 0.93, 95%CI: 0.84–1.03, P = 0.148). In conclusion, this meta-analysis provides strong evidence that ALDH2 rs671 polymorphism may be associated with increased risks of CAD and MI. However, further studies are still needed to accurately determine whether ADH genetic polymorphisms are associated with susceptibility to CAD and MI. 相似文献
30.
Xiaofei Lv Yuan Zhang Shaoqi Rao Dongfang Su Dan Feng Min Wang Xinrui Li Dan Li Honghui Guo Xiaoyu Zuo Min Xia Haimei Ouyang Wenhua Ling Jian Qiu 《Gene》2013
Studies focusing on the association of gene methylthioadenosine phosphorylase (MTAP) with the risk of coronary artery disease (CAD) and myocardial infarction (MI) are limited. 相似文献