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Sample records for irreversible myocardial injury

  1. Recognition of reversible and irreversible myocardial injury by technetium pyrophosphate extraction kinetics

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    Silva, R.; Chen, Y.F.; Sell, T.L.; Lowe, J.E.; Jones, R.H.

    1987-07-01

    The need for a more accurate method of detecting episodes of myocardial ischemia during cardiac operations, particularly during the ischemic arrest interval, prompted us to investigate the usefulness of measuring the active extraction of technetium pyrophosphate in identifying and quantitating ischemic injury. Twenty-four adult mongrel dogs were subjected to cardiopulmonary bypass, and normothermic global ischemia was induced by cross-clamping the proximal aorta. Technetium pyrophosphate (1 mCi) was injected through a standard cardioplegia line with normal saline, simulating administration of cardioplegic solution, upon placement of the aortic cross-clamp (time 0), at 15, 30, 45, and 60 minutes of global ischemia, and with the onset and completion of ischemic contracture. Radioactive counts were recorded over the heart at 1 second intervals, and the extraction fraction and half-time of clearance were calculated. The extraction fraction increased from 0.22 at time 0 to 0.58 at 15 minutes, 0.82 at 30 minutes, 0.85 at 45 minutes, and 0.91 at 60 minutes. The halftime increased from a baseline of 114 seconds (time 0) to a maximum of 321 seconds at 60 minutes of ischemia. The onset and completion of ischemic contracture showed a return toward baseline of both the extraction fraction and halftime of clearance, with an extraction fraction of 0.44 and 0.46 and a halftime of 135 and 133 seconds, respectively. These data clearly show that reversible myocardial injury increased the extraction and reduced the clearance of technetium pyrophosphate and that the magnitude of change related to the extent of injury. The progression to irreversible myocardial injury decreased the active extraction of technetium pyrophosphate. This simple procedure for real-time documentation of myocardial injury promises to provide easily obtainable endpoints of injury for use during cardiac operations in humans.

  2. Myocardial Infarction Type 2 and Myocardial Injury

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    Sandoval, Yader; Thygesen, Kristian

    2017-01-01

    BACKGROUND: The development and implementation of sensitive and high-sensitivity cardiac troponin assays has not only expedited the early ruling in and ruling out of acute myocardial infarction, but has also contributed to the identification of patients at risk for myocardial injury with necrosis......, as confirmed by the presence of cardiac troponin concentrations above the 99th percentile. Myocardial injury with necrosis may occur either in the presence of overt ischemia from myocardial infarction, or in the absence of overt ischemia from myocardial injury accompanying other conditions. Myocardial...... infarction type 2 (T2MI) has been a focus of attention; conceptually T2MI occurs in a clinical setting with overt myocardial ischemia where a condition other than an acute atherothrombotic event is the major contributor to a significant imbalance between myocardial oxygen supply and/or demand. Much debate...

  3. CMR Native T1 Mapping Allows Differentiation of Reversible Versus Irreversible Myocardial Damage in ST-Segment-Elevation Myocardial Infarction: An OxAMI Study (Oxford Acute Myocardial Infarction).

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    Liu, Dan; Borlotti, Alessandra; Viliani, Dafne; Jerosch-Herold, Michael; Alkhalil, Mohammad; De Maria, Giovanni Luigi; Fahrni, Gregor; Dawkins, Sam; Wijesurendra, Rohan; Francis, Jane; Ferreira, Vanessa; Piechnik, Stefan; Robson, Matthew D; Banning, Adrian; Choudhury, Robin; Neubauer, Stefan; Channon, Keith; Kharbanda, Rajesh; Dall'Armellina, Erica

    2017-08-01

    CMR T1 mapping is a quantitative imaging technique allowing the assessment of myocardial injury early after ST-segment-elevation myocardial infarction. We sought to investigate the ability of acute native T1 mapping to differentiate reversible and irreversible myocardial injury and its predictive value for left ventricular remodeling. Sixty ST-segment-elevation myocardial infarction patients underwent acute and 6-month 3T CMR, including cine, T2-weighted (T2W) imaging, native shortened modified look-locker inversion recovery T1 mapping, rest first pass perfusion, and late gadolinium enhancement. T1 cutoff values for oedematous versus necrotic myocardium were identified as 1251 ms and 1400 ms, respectively, with prediction accuracy of 96.7% (95% confidence interval, 82.8% to 99.9%). Using the proposed threshold of 1400 ms, the volume of irreversibly damaged tissue was in good agreement with the 6-month late gadolinium enhancement volume (r=0.99) and correlated strongly with the log area under the curve troponin (r=0.80) and strongly with 6-month ejection fraction (r=-0.73). Acute T1 values were a strong predictor of 6-month wall thickening compared with late gadolinium enhancement. Acute native shortened modified look-locker inversion recovery T1 mapping differentiates reversible and irreversible myocardial injury, and it is a strong predictor of left ventricular remodeling in ST-segment-elevation myocardial infarction. A single CMR acquisition of native T1 mapping could potentially represent a fast, safe, and accurate method for early stratification of acute patients in need of more aggressive treatment. Further confirmatory studies will be needed. © 2017 The Authors.

  4. Oxytocin ameliorates the immediate myocardial injury in heart transplant through down regulation of the neutrophil dependent myocardial apoptosis

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    F Fadhil Al-Amran

    2014-01-01

    Conclusion: Oxytocin ameliorates myocardial injury in heart transplant through down-regulation the myocardial inflammatory response, reactive oxygen species, and neutrophil-dependant myocardial apoptosis.

  5. Severe myocardial injury and extracorporeal membrane oxygenation following perinatal asphyxia

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    P. Benson Ham

    2015-05-01

    Full Text Available Perinatal asphyxia is a common cause of morbidity and mortality in the newborn and is associated with myocardial injury in a significant proportion of cases. Biomarkers, echocardiography, and rhythm disturbances are sensitive indicators of myocardial ischemia and may predict mortality. We present a case of severe myocardial dysfunction immediately after delivery managed with extracorporeal membrane oxygenation (ECMO and discuss the role of cardiac biomarkers, echocardiography, electrocardiography, and ECMO in the asphyxiated newborn.

  6. Clinical Characteristics and Outcomes of Patients with Myocardial Infarction, Myocardial Injury, and Nonelevated Troponins

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    Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S

    2015-01-01

    was diagnosed in cases of a cardiac troponin I increase or decrease pattern with at least 1 value >30 ng/L (99th percentile) together with myocardial ischemia. Myocardial injury was defined as cardiac troponin I values >30 ng/L, but without signs or symptoms indicating overt cardiac ischemia. Patients with peak...

  7. Treatment and outcomes of type 2 myocardial infarction and myocardial injury compared with type 1 myocardial infarction.

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    Smilowitz, Nathaniel R; Subramanyam, Pritha; Gianos, Eugenia; Reynolds, Harmony R; Shah, Binita; Sedlis, Steven P

    2017-07-25

    Type 2 myocardial infarction (MI) is defined by a rise and fall of cardiac biomarkers and evidence of ischemia without unstable coronary artery disease (CAD) because of a mismatch in myocardial oxygen supply and demand. Myocardial injury is similar but does not fulfill the clinical criteria for MI. There is uncertainty in terms of the clinical characteristics, management, and outcomes of type 2 MI and myocardial injury in comparison with type 1 MI. Patients admitted to a Veterans Affairs tertiary care hospital with a rise and fall in cardiac troponin were identified. MI and injury subtypes, presentation, management, and outcomes were determined. Type 1 MI, type 2 MI, and myocardial injury occurred in 137, 146, and 175 patients, respectively. Patients with type 2 MI were older (P=0.02), had lower peak cardiac troponin (P<0.001), and were less likely to receive aspirin and statin at discharge (P<0.001) than type 1 MI survivors. All-cause mortality (median follow-up: 1.8 years) was not different between patient groups (type 1 MI mortality: 29.9%, type 2 MI: 30.8%, myocardial injury: 29.7%; log rank P=0.94). A significant proportion of deaths were attributed to cardiovascular causes in all subgroups (type 1 MI: 34.1%, type 2 MI: 17.8%, myocardial injury: 30.8%). Patients with type 2 MI and myocardial injury were less likely to receive medical therapy for CAD than those with type 1 MI. No differences in all-cause mortality among MI subtypes were observed. Additional studies to determine optimal medical therapy and risk stratification strategies for these high-risk populations are warranted.

  8. Combretastatin A4 disodium phosphate-induced myocardial injury

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    Tochinai, Ryota; Nagata, Yuriko; Ando, Minoru; Hata, Chie; Suzuki, Tomo; Asakawa, Naoyuki; Yoshizawa, Kazuhiko; Uchida, Kazumi; Kado, Shoichi; Kobayashi, Toshihide; Kaneko, Kimiyuki; Kuwahara, Masayoshi

    2016-01-01

    Histopathological and electrocardiographic features of myocardial lesions induced by combretastatin A4 disodium phosphate (CA4DP) were evaluated, and the relation between myocardial lesions and vascular changes and the direct toxic effect of CA4DP on cardiomyocytes were discussed. We induced myocardial lesions by administration of CA4DP to rats and evaluated myocardial damage by histopathologic examination and electrocardiography. We evaluated blood pressure (BP) of CA4DP-treated rats and effects of CA4DP on cellular impedance-based contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). The results revealed multifocal myocardial necrosis with a predilection for the interventricular septum and subendocardial regions of the apex of the left ventricular wall, injury of capillaries, morphological change of the ST junction, and QT interval prolongation. The histopathological profile of myocardial lesions suggested that CA4DP induced a lack of myocardial blood flow. CA4DP increased the diastolic BP and showed direct effects on hiPS-CMs. These results suggest that CA4DP induces dysfunction of small arteries and capillaries and has direct toxicity in cardiomyocytes. Therefore, it is thought that CA4DP induced capillary and myocardial injury due to collapse of the microcirculation in the myocardium. Moreover, the direct toxic effect of CA4DP on cardiomyocytes induced myocardial lesions in a coordinated manner. PMID:27559241

  9. Monitoring of myocardial injury after noncardiac surgery

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    van Waes, JAR|info:eu-repo/dai/nl/341538973

    2017-01-01

    Background Postoperative myocardial infarction (POMI) is an important complication after noncardiac surgery, that is associated with increased risk of mortality. In order to improve prognosis, routine postoperative monitoring with cardiac biomarkers is recommended to identify patients at risk for PO

  10. Trans-system mechanisms against ischemic myocardial injury.

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    Liu, Shu Q; Ma, Xin-Liang; Qin, Gangjian; Liu, Qingping; Li, Yan-Chun; Wu, Yu H

    2015-01-01

    A mammalian organism possesses a hierarchy of naturally evolved protective mechanisms against ischemic myocardial injury at the molecular, cellular, and organ levels. These mechanisms comprise regional protective processes, including upregulation and secretion of paracrine cell-survival factors, inflammation, angiogenesis, fibrosis, and resident stem cell-based cardiomyocyte regeneration. There are also interactive protective processes between the injured heart, circulation, and selected remote organs, defined as trans-system protective mechanisms, including upregulation and secretion of endocrine cell-survival factors from the liver and adipose tissue as well as mobilization of bone marrow, splenic, and hepatic cells to the injury site to mediate myocardial protection and repair. The injured heart and activated remote organs exploit molecular and cellular processes, including signal transduction, gene expression, cell proliferation, differentiation, migration, mobilization, and/or extracellular matrix production, to establish protective mechanisms. Both regional and trans-system cardioprotective mechanisms are mediated by paracrine and endocrine messengers and act in coordination and synergy to maximize the protective effect, minimize myocardial infarction, and improve myocardial function, ensuring the survival and timely repair of the injured heart. The concept of the trans-system protective mechanisms may be generalized to other organ systems-injury in one organ may initiate regional as well as trans-system protective responses, thereby minimizing injury and ensuring the survival of the entire organism. Selected trans-system processes may serve as core protective mechanisms that can be exploited by selected organs in injury. These naturally evolved protective mechanisms are the foundation for developing protective strategies for myocardial infarction and injury-induced disorders in other organ systems.

  11. Acute right ventricular myocardial injury and sudden cardiac arrest in a patient with persistent spontaneous coronary vasospasm

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    Hung Ming-Yow; Li Ju-Chi; Hao Wen-Rui; Wu Cheng-Hsueh; Hung Ming-Jui

    2011-01-01

    Coronary vasospasm is a rare diagnosis resulting in sudden arrhythmic cardiac arrest. We report a case of a healthy,non-smoking elderly woman resuscitated from arrhythmic cardiac arrest. She had persistent spontaneous coronaxy vasospasm, leading to right ventricular myocardial injury and failure, and shock. She responded quickly to intravenous normal saline bolus infusion, but had irreversible neurological sequelae. Additionally, she had atrial fibrillation preceding ischemic ventricular fibrillation, a rare finding in coronary vasospasm-related cardiac arrest. We suggest immediate coronary angiography of patients in sudden arrhythmic cardiac arrest with acute right ventricular failure for a prompt,accurate diagnosis and appropriate management of the coronary vasospasm.

  12. Left ventricular hypertrophy: an initial response to myocardial injury.

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    Francis, G S; McDonald, K M

    1992-06-04

    The prevailing wisdom generally has been that the failing heart hypertrophies in response to increased wall stress. The increase in myocardial mass observed in heart failure is therefore a relatively late compensatory event geared to normalize wall stress. Although this is undoubtedly true, especially for heart failure resulting from a large anterior myocardial infarction accompanied by rapid left ventricular expansion, it is possible that an important form of hypertrophy occurs much earlier as an initial response to myocardial injury. One can hypothesize that the initial response to injury is a nonspecific phenotypic alteration of the cardiac myocyte to one of growth and development. Such changes may be driven by both trophic and mechanical forces and may be important in altering the architecture of the myocardial cell and surrounding cardiac interstitium. Preliminary data from a variety of models support the concept that neuroendocrine activity is an important component in the ventricular remodeling process, and that pharmacologic interventions designed to block systemic and tissue neuroendocrine activity may prevent excessive cardiac enlargement and its ultimate consequences. Because this concept has important implications for preventive cardiology, the results of several prevention trials, including the Cooperative North Scandinavian Enalapril Survival Study (CONSENSUS), Studies of Left Ventricular Dysfunction (SOLVD), and Survival and Ventricular Enlargement (SAVE) are awaited eagerly.

  13. Cholinergic anti-inflammatory pathway: a possible approach to protect against myocardial ischemia reperfusion injury

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    XIONG Jun; XUE Fu-shan; YUAN Yu-jing; WANG Qiang; LIAO Xu; WANG Wei-li

    2010-01-01

    Objective A general review was made of studies involving: (1) the concept and mechanism of the cholinergic anti-inflammatory pathway (CAP), (2) the important role of inflammatory response in myocardial ischemia reperfusion (I/R)injury and (3) the evidence and mechanisms by which CAP may provide protection against myocardial I/R injury.Data sources The data used in this review were mainly from manuscripts listed in PubMed that were published in English from 1987 to 2009. The search terms were "vagal nerve stimulation", "myocardial ischemia reperfusion injury","nicotine acetylcholine receptor" and "inflammation".Study selection (1) Clinical and experimental evidence that the inflammatory response induced by reperfusion enhances myocardial I/R injury. (2) Clinical and laboratory evidence that the CAP inhibits the inflammation and provides protection against myocardial I/R injury.Results The myocardial I/R injury is really an inflammatory process characterized by recruitment of neutrophils into the ischemic myocardium and excessive production of pro-inflammatory cytokines. Because the CAP can modulate the inflammatory response by decreasing the production and release of pro-inflammatory cytokines, it can provide protection against myocardial I/R injury.Conclusions The CAP can inhibit the inflammatory response induced by reperfusion and protect against myocardial I/R injury. It represents an exciting opportunity to develop new and novel therapeutics to attenuate the myocardial I/R injury.

  14. Ablation of cereblon attenuates myocardial ischemia-reperfusion injury.

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    Kim, Jooyeon; Lee, Kwang Min; Park, Chul-Seung; Park, Woo Jin

    2014-05-16

    Cereblon (CRBN) was originally identified as a target protein for a mild type of mental retardation in humans. However, recent studies showed that CRBN acts as a negative regulator of AMP-activated protein kinase (AMPK) by binding directly to the AMPK catalytic subunit. Because AMPK is implicated in myocardial ischemia-reperfusion (I-R) injury, we reasoned that CRBN might play a role in the pathology of myocardial I-R through regulation of AMPK activity. To test this hypothesis, wild-type (WT) and crbn knockout (KO) mice were subjected to I-R (complete ligation of the coronary artery for 30 min followed by 24h of reperfusion). We found significantly smaller infarct sizes and less fibrosis in the hearts of KO mice than in those of WT mice. Apoptosis was also significantly reduced in the KO mice compared with that in WT mice, as shown by the reduced numbers of TUNEL-positive cells. In parallel, AMPK activity remained at normal levels in KO mice undergoing I-R, whereas it was significantly reduced in WT mice under the same conditions. In rat neonatal cardiomyocytes, overexpression of CRBN significantly reduced AMPK activity, as demonstrated by reductions in both phosphorylation levels of AMPK and the expression of its downstream target genes. Collectively, these data demonstrate that CRBN plays an important role in myocardial I-R injury through modulation of AMPK activity.

  15. Macrophage depletion impairs wound healing and increases left ventricular remodeling after myocardial injury in mice

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    van Amerongen, Machteld J.; Harmsen, Martin C.; van Rooijen, Nico; Petersen, Arjen H.; van Luyn, Marja J. A.

    2007-01-01

    Macrophages have been suggested to be beneficial for myocardial wound healing. We investigated the role of macrophages in myocardial wound healing by inhibition of macrophage infiltration after myocardial injury. We used a murine cryoinjury model to induce left ventricular damage. Infiltrating macro

  16. Role of E-selectin for diagnosing myocardial injury in paediatric patients with mycoplasma pneumoniae pneumonia.

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    Deng, Ming-Hong; Lin, Chun-Wang; Sun, Yan-Na; Zeng, Xiang-Lin; Wen, Fang

    2017-01-01

    Backgrounds Effects of myocardial injury on E-selectin remain unclear. Thus, we investigated the diagnostic value of E-selectin for myocardial injury in paediatric patients with mycoplasma pneumoniae pneumonia. Methods In this prospective and blinded clinical study, plasma E-selectin, cardiac troponin I, creatine kinase isoenzyme MB, interleukin-6 and tumor necrosis factor alpha concentrations were measured in paediatric patients with mycoplasma pneumoniae pneumonia (MPP group, n = 138). The control group comprised 120 healthy children. The definition of cardiac injury was based on cardiac troponin I or CK-MB (with or possibly without abnormal electrocardiogram evidence). Diagnostic value of E-selectin for myocardial injury was determined by analysing receiver operating characteristic curves. Results Among the 138 mycoplasma pneumoniae pneumonia patients, 40 patients were identified with myocardial injury, while 98 patients were identified without myocardial injury. Plasma E-selectin concentrations were: 40.22 ± 4.80 ng/mL, in patients with myocardial injury; 18.55 ± 2.16 ng/mL, in patients without myocardial injury and 12.39 ± 3.27 ng/mL, in healthy children. For the 40 patients identified with myocardial injury, area under the receiver operating characteristic curve value for plasma E-selectin concentrations was 0.945 (95% CI: 0.899-0.991), and optimal diagnostic cut-off value was 29.93 ng/mL (positive likelihood ratio = 72.5). Conclusion E-selectin was shown to be an effective index for myocardial injury in paediatric patients with mycoplasma pneumoniae pneumonia, and its role in other causes of myocardial injury warrants further investigation.

  17. Calpain system and its involvement in myocardial ischemia and reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Christiane; Neuhof; Heinz; Neuhof

    2014-01-01

    Calpains are ubiquitous non-lysosomal Ca2+-dependent cysteine proteases also present in myocardial cytosol and mitochondria.Numerous experimental studies reveal an essential role of the calpain system in myocardial injury during ischemia,reperfusion and postischemic structural remodelling.The increasing Ca2+-content and Ca2+-overload in myocardial cytosol and mitochondria during ischemia and reperfusion causes an activation of calpains.Upon activation they are able to injure the contractile apparatus and impair the energy production by cleaving structural and functional proteins of myocytes and mitochondria.Besides their causal involvement in acute myocardial dysfunction they are also involved in structural remodelling after myocardial infarction by the generation and release of proapoptotic factors from mitochondria.Calpain inhibition can prevent or attenuate myocardial injury during ischemia,reperfusion,and in later stages of myocardial infarction.

  18. Phellinus linteus Mycelium Alleviates Myocardial Ischemia-Reperfusion Injury through Autophagic Regulation

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    Su, Hsing-Hui; Chu, Ya-Chun; Liao, Jiuan-Miaw; Wang, Yi-Hsin; Jan, Ming-Shiou; Lin, Chia-Wei; Wu, Chiu-Yeh; Tseng, Chin-Yin; Yen, Jiin-Cherng; Huang, Shiang-Suo

    2017-01-01

    The incidence of myocardial ischemia-reperfusion (IR) injury is rapidly increasing around the world and this disease is a major contributor to global morbidity and mortality. It is known that regulation of programmed cell death including apoptosis and autophagy reduces the impact of myocardial IR injury. In this study, the cardioprotective effects and underlying mechanisms of Phellinus linteus (Berk. and Curt.) Teng, Hymenochaetaceae (PL), a type of medicinal mushroom, were examined in rats subjected to myocardial IR injury. The left main coronary artery of rats was ligated for 1 h and reperfused for 3 h. The arrhythmia levels were monitored during the entire process and the infarct size was evaluated after myocardial IR injury. Furthermore, the expression levels of proteins in apoptotic and autophagic pathways were observed. Pretreatment with PL mycelium (PLM) significantly reduced ventricular arrhythmia and mortality due to myocardial IR injury. PLM also significantly decreased myocardial infarct size and plasma lactate dehydrogenase level after myocardial IR injury. Moreover, PLM administration resulted in decreased caspase 3 and caspase 9 activation and increased Bcl-2/Bax ratio. Phosphorylation level of AMPK was elevated while mTOR level was reduced. Becline-1 and p62 levels decreased. These findings suggest that PLM is effective in protecting the myocardium against IR injury. The mechanism involves mediation through suppressed pro-apoptotic signaling and regulation of autophagic signaling, including stimulation of AMPK-dependent pathway and inhibition of beclin-1-dependent pathway, resulting in enhancement of protective autophagy and inhibition of excessive autophagy. PMID:28420993

  19. Protection effects of Sigmart for no-reflow or myocardial reperfusion injury after undergoing PCI surgery

    Institute of Scientific and Technical Information of China (English)

    Xiao-Peng Wu; Xuan-Qi Wang; Lei-Sen Han; Chong-Zhen Wang; Yin-Juan Mao; Wei-Jie Li

    2015-01-01

    Objective:To study the protection effects of Sigmart for lack of reflow or myocardial myocardial reperfusion injury after undergoing PCI surgery.Methods: A total of 150 patients undergoing PCI surgery were selected and divided into control group and observation group with 75 cases in each group. After undergoing the surgery, both groups were given low molecular heparin 4 100 IU for 3 d, 100 mg + aspirin + atorvastatin 20 mg + clopidogrel 75 mg. 5 mL of blood specimen were collected for detection of troponin I (TnI), myocardial enzyme spectrum (CK, CK-MB) level to evaluate myocardial myocardial reperfusion injury after undergoing PCI surgery. Also electrocardiogram (ECG) were detected. Six months after the surgery, effects of Sigmart for lack of reflow or myocardial myocardial reperfusion injury after undergoing PCI surgery were evaluated.Results: 1, 6, 12, 24 h after the surgery, TnI, Mb, CK-Mb levels of were significant different from those before undergoing the surgery, and these levels of the observation group were significant higher than that of the control group. ST segment elevation at 2, 12, and 24 h after undergoing the surgery were significant obvious than that of the control group. According to the follow up, incidence of comprehensive end point event was significant higher than that of the control group. SAQ and SF-36 scores of the two groups were significant different. Conclusion: Sigmart shows good protection effects for lack of reflow or myocardial myocardial reperfusion injury after undergoing PCI surgery.

  20. Cellular recruitment in myocardial ischaemia/reperfusion injury.

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    Bonaventura, Aldo; Montecucco, Fabrizio; Dallegri, Franco

    2016-06-01

    Myocardial infarction (MI) is strictly linked to atherosclerosis. Beyond the mechanical narrowing of coronary vessels lumen, during MI a great burden of inflammation is carried out. One of the crucial events is represented by the ischaemia/reperfusion injury, a complex event involving inflammatory cells (such as neutrophils, platelets, monocytes/macrophages, lymphocytes and mast cells) and key activating signals (such as cytokines, chemokines and growth factors). Cardiac repair following myocardial infarction is dependent on a finely regulated response involving a sequential recruitment and the clearance of different subsets of inflammatory cells. This narrative review was based on the works detected on PubMed and MEDLINE up to November 2015. Infarct healing classically follows three overlapping phases: the inflammatory phase, in which the innate immune pathways are activated and inflammatory leucocytes are recruited in order to clear the wound from dead cells; the proliferative phase, characterized by the suppression of pro-inflammatory signalling and infiltration of 'repairing' cells secreting matrix proteins in the injured area; and the maturation phase, which is associated with the quiescence and the elimination of the reparative cells together with cross-linking of the matrix. All these phases are timely regulated by the production of soluble mediators, such as cytokines, chemokines and growth factors. Targeting inflammatory cell recruitment early during reperfusion and healing might be promising to selectively inhibit injury and favour repair. This approach might substantially improve adverse postischaemic left ventricle remodelling, characterized by dilation, hypertrophy of viable segments and progressive dysfunction. © 2016 Stichting European Society for Clinical Investigation Journal Foundation.

  1. Kaempferol Attenuates Myocardial Ischemic Injury via Inhibition of MAPK Signaling Pathway in Experimental Model of Myocardial Ischemia-Reperfusion Injury

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    Kapil Suchal

    2016-01-01

    Full Text Available Kaempferol (KMP, a dietary flavonoid, has antioxidant, anti-inflammatory, and antiapoptotic effects. Hence, we investigated the effect of KMP in ischemia-reperfusion (IR model of myocardial injury in rats. We studied male albino Wistar rats that were divided into sham, IR-control, KMP-20 + IR, and KMP 20 per se groups. KMP (20 mg/kg; i.p. was administered daily to rats for the period of 15 days, and, on the 15th day, ischemia was produced by one-stage ligation of left anterior descending coronary artery for 45 min followed by reperfusion for 60 min. After completion of surgery, rats were sacrificed; heart was removed and processed for biochemical, morphological, and molecular studies. KMP pretreatment significantly ameliorated IR injury by maintaining cardiac function, normalizing oxidative stress, and preserving morphological alterations. Furthermore, there was a decrease in the level of inflammatory markers (TNF-α, IL-6, and NFκB, inhibition of active JNK and p38 proteins, and activation of ERK1/ERK2, a prosurvival kinase. Additionally, it also attenuated apoptosis by reducing the expression of proapoptotic proteins (Bax and Caspase-3, TUNEL positive cells, and increased level of antiapoptotic proteins (Bcl-2. In conclusion, KMP protected against IR injury by attenuating inflammation and apoptosis through the modulation of MAPK pathway.

  2. Prognostic Impact of Myocardial Injury Related to Various Cardiac and Noncardiac Conditions

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    Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S;

    2016-01-01

    were classified into 5 categories of plausible related conditions: cardiac ischemic, cardiac nonischemic, noncardiac, multifactorial, or indeterminate. Follow-up was a minimum of 3 years, with all-cause mortality as the single end-point. RESULTS: A total of 3762 patients were considered, of whom 1089......BACKGROUND: Elevated cardiac troponins in clinical conditions other than myocardial infarction are well known. For such occurrences, the term "myocardial injury" has been proposed. The long-term outcome in patients with myocardial injury related to various cardiac and noncardiac clinical disorders...... is unknown. METHODS: During January 2010 to January 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. Patients with cardiac troponin I values >30 ng/L and no evidence of myocardial ischemia were diagnosed as having myocardial injury. Patients...

  3. Effect of small dose of EPO after PCI on cardiac function and myocardial injury in patients with acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    Guo-Min Li

    2016-01-01

    Objective:To study the effect of small dose of erythropoietin (EPO) after PCI on cardiac function and myocardial injury in patients with acute myocardial infarction.Methods:A total of 86 patients with acute ST-elevation myocardial infarction who received percutaneous coronary intervention in our hospital from April 2012 to June 2015 were selected and randomly divided into EPO group and control group, serum was collected 1 week after operation to determine myocardial injury indexes, inflammation indexes, oxidative stress indexes and ventricular remodeling indexes, and color Doppler echocardiography was conducted 6 months after surgery to determine ventricular systolic and diastolic function indexes.Results:One week after operation, serum LDH, CK, CK-MB, cTnI, cTnT, sCD40L, E-selectin, P-selectin, sICAM-1, MDA, O2-, ox-LDL, PICP, CITP and PIIINP levels of EPO group were significantly lower than those of control group while GSH-Px and SOD levels were significantly higher than those of control group; 6 months after operation, LVEF of EPO group was significantly higher than that of control group while LVEDVI and LVESVI were significantly lower than those of control group.Conclusions:Small dose of EPO after PCI can alleviate myocardial damage, relieve inflammation and oxidative stress, and improve myocardial remodeling and cardiac diastolic and systolic function in patients with AMI.

  4. Physiologically tolerable insulin reduces myocardial injury and improves cardiac functional recovery in myocardial ischemic/reperfused dogs.

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    Zhang, Hang-Xiang; Zang, Yi-Min; Huo, Jian-Hua; Liang, Shao-Jun; Zhang, Hai-Feng; Wang, Yue-Min; Fan, Qian; Guo, Wen-Yi; Wang, Hai-Chang; Gao, Feng

    2006-12-01

    This study was designed to examine whether physiologically tolerable insulin, which maintains lower blood glucose, can protect the myocardium against ischemia/reperfusion (I/R) injury in a preclinical large animal model. Adult dogs were subjected to 50 minutes of myocardial ischemia (80% reduction in coronary blood flow) followed by 4 hours of reperfusion and treated with vehicle, glucose-insulin-potassium (GIK; glucose, 250 g/L; insulin, 60 U/L; potassium, 80 mmol/L), GK, or low-dose insulin (30 U/L) 10 minutes before reperfusion. Treatment with GIK exerted significant cardioprotective effects as evidenced by improved cardiac function, improved coronary blood flow, reduced infarct size, and myocardial apoptosis. In contrast, treatment with GK increased blood glucose level and aggravated myocardial I/R injury. It is interesting that treatment with insulin alone at the dose that reduced blood glucose to a clinically tolerable level exerted significant cardioprotective effects that were comparable to that seen in the GIK-treated group. This low-dose insulin had no effect on coronary blood flow after reperfusion but markedly reduced coronary reactive hyperemia and switched myocardial substrate uptake from fat to carbohydrate. Our results suggest that lower glucose supply to the ischemic myocardium at early reperfusion may create a "metabolic postconditioning" and thus reduce myocardial ischemia/reperfusion injury after prolonged reperfusion.

  5. Humanized cobra venom factor decreases myocardial ischemia-reperfusion injury.

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    Gorsuch, W Brian; Guikema, Benjamin J; Fritzinger, David C; Vogel, Carl-Wilhelm; Stahl, Gregory L

    2009-12-01

    Cobra venom factor (CVF) is a complement activating protein in cobra venom, which functionally resembles C3b, and has been used for decades for decomplementation of serum to investigate the role of complement in many model systems of disease. The use of CVF for clinical practice is considered impractical because of immunogenicity issues. Humanization of CVF was recently demonstrated to yield a potent CVF-like molecule. In the present study, we demonstrate that mice treated with recombinant humanized CVF (HC3-1496) are protected from myocardial ischemia-reperfusion (MI/R) injuries with resultant preservation of cardiac function. Also, C3 deposition in the myocardium following MI/R was not observed following treatment with HC3-1496. HC3-1496 led to complement activation and depletion of C3, but preserved C5 titers. These data suggest, unlike CVF, HC3-1496 does not form a C5 convertase in the mouse, similar to recent studies in human sera/plasma. These results suggest that humanized CVF (HC3-1496) protects the ischemic myocardium from reperfusion injuries induced by complement activation and represents a novel anti-complement therapy for potential clinical use.

  6. Correlation between deceleration capacity of rate and myocardial injury degree in children with viral myocarditis

    Institute of Scientific and Technical Information of China (English)

    Jing-Yang Zhang; Hui Wu

    2016-01-01

    Objective:To find the correlation between deceleration capacity of rate and myocardial injury degree in children with viral myocarditis.Methods:A total of 90 children with viral myocarditis and 86 healthy children were selected as the research subjects, differences in rate deceleration capacity of rate and myocardial damage degree indexes were compared between two groups of children, and the correlation between deceleration capacity of rate and myocardial injury degree was further analyzed.Results:Mean DC level as well as heart rate variability indexes SDNN, SDANN, RMSSD, LF and HF levels of observation group was lower than those of control group; serum myocardial enzyme spectrum indexes CK, CK-MB, cTnⅠ, LDH, AST and ALT content were higher than those of control group; serum apoptosis indexes GRBS, sFasL, Bax and caspase-3 content were higher than those of control group while Bcl-2 content was lower than that of control group; heart rate indexes MSV1, MSV2, MSV3, PFVe and PFVa levels were lower than those of control group. Deceleration capacity of rate in children with viral myocarditis was directly correlated with myocardial injury-related indexes such as heart rate variability, myocardial enzyme spectrum, myocardial apoptosis and heart rate.Conclusions: The change of deceleration capacity of rate in children with viral myocarditis is directly correlated with myocardial injury, and can be used as a reliable medium for disease severity judgment and clinical treatment guidance.

  7. Large myocardial infarction with myocardium calcium deposits associated with reperfusion injury.

    Science.gov (United States)

    Rios, Elisabete; Mancio, Jennifer; Rodrigues-Pereira, Pedro; Magalhães, Domingos; Bartosch, Carla

    2014-01-01

    The clinical and autopsy findings of a 66-year-old man with myocardial infarction complicated by reperfusion injury are described, highlighting the presence of large myocardium calcium deposits. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Acute myocardial injury caused by Sydney funnel-web spider (Atrax robustus) envenoming.

    Science.gov (United States)

    Isbister, G K; Warner, G

    2003-12-01

    A 67-year-old female suffered envenoming by a Sydney funnel-web spider (Atrax robustus), complicated by ST elevation and elevated troponin levels consistent with an acute myocardial injury. She was treated primarily with funnel-web spider antivenom, admission to intensive care and initial respiratory support for acute pulmonary oedema. The mechanism by which funnel-web spider envenomation caused myocardial injury is unclear but follow-up nuclear studies in the patient demonstrated that she had minimal atherosclerotic disease.

  9. Pressure injuries in elderly with acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Komici K

    2017-09-01

    Full Text Available Klara Komici,1 Dino F Vitale,2 Dario Leosco,1 Angela Mancini,1 Graziamaria Corbi,3 Leonardo Bencivenga,1 Alessandro Mezzani,4 Bruno Trimarco,5 Carmine Morisco,5 Nicola Ferrara,1,2 Giuseppe Rengo1,2 1Division of Geriatrics, Department of Translational Medical Sciences, University of Naples Federico II, Naples, Italy; 2Cardiac Rehabilitation Division, Salvatore Maugeri Foundation, IRCCS, Scientific Institute of Telese Terme (BN, Telese Terme, Italy; 3Department of Medicine and Health Sciences, University of Molise Campobasso, Campobasso, Italy; 4Cardiac Rehabilitation Division, Salvatore Maugeri Foundation, IRCCS, Scientific Institute of Veruno, Veruno, Italy; 5Division of Cardiology, Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy Objectives: To assess pressure injury (PI incidence among patients hospitalized for acute myocardial infarction (AMI in an intensive coronary care unit (ICCU and to detect the impact of specific risk factors on the development of PI in this clinical setting.Patients and methods: Prospective cohort study in ICCU setting. Patients admitted for AMI: patients mean age 67.5±11.5 years (n=165. Norton Scale, Mini Nutritional Assessment (MNA, demographic, clinical and biochemical data collected at the time of ICCU admission have been tested in a logistic model to assess the odds ratios (ORs of PI risk development. The jackknifed area under the receiver operating characteristic curve (AUC and the decision curve analysis have been employed to assess the additive predictive value of a factor.Results: Twenty-seven (16.3% patients developed PIs. An increased PI risk was associated with advanced age (OR =2.5 every 10-year increase; 95% CI =1.1–5.7, while probability of PI development was reduced in patients with higher left ventricular ejection fraction (LVEF (OR =0.4 every 5% increase; 95% CI =0.24–0.66, MNA score (OR =0.65 every unit change; 95% CI =0.44–0.95 and Norton Scale score

  10. Pharmacological preconditioning with hyperbaric oxygen: can this therapy attenuate myocardial ischemic reperfusion injury and induce myocardial protection via nitric oxide?

    Science.gov (United States)

    Yogaratnam, Jeysen Zivan; Laden, Gerard; Guvendik, Lavent; Cowen, Mike; Cale, Alex; Griffin, Steve

    2008-09-01

    Ischemic reperfusion injury (IRI) is an inevitable part cardiac surgery such as coronary artery bypass graft (CABG). While ischemic hypoxia and the ensuing normoxic or hyperoxic reperfusion are critical to the initiation and propagation of IRI, conditioning myocardial cells to an oxidative stress prior to IRI may limit the consequences of this injury. Hyperbaric oxygen (HBO2) is a modality of treatment that is known to generate an oxidative stress. Studies have shown that treatment with HBO2 postischemia and reperfusion is useful in ameliorating myocardial IRI. Moreover, preconditioning the myocardium with HBO2 before reperfusion has demonstrated a myocardial protective effect by limiting the infarct size post ischemia and reperfusion. Current evidence suggests that HBO2 preconditioning may partly attenuate IRI by stimulating the endogenous production of nitric oxide (NO). As NO has the capacity to reduce neutrophil sequestration, adhesion and associated injury, and improve vascular flow, HBO2 preconditioning induced NO may play a role in providing myocardial protection during interventions that involve an inevitable episode of IRI. This current opinion review article attempts to suggest that HBO2 may be used to pharmacologically precondition and protect the myocardium from the effects of IRI that is known to occur during cardiac surgery.

  11. Cardioprotective Effects of HuoxueAnshen Recipe against Myocardial Injuries Induced by Sleep Deprivation in Rats

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    Rong Yuan

    2017-01-01

    Full Text Available Background. Traditional Chinese Medicine is extensively used in China and HuoxueAnshen Recipe (HAR was formulated according to its method in treating CHD accompanied with insomnia in clinic. However, there are few studies related to the effect of HAR on myocardial injury and sleep disorders. Purpose. To investigate the effects of HAR on sleep deprivation- (SD- induced myocardial I/R injury. Methods. Male Wistar rats receiving a daily gavage of HAR or vehicle were exposed to SD intervention while control rats had normal sleep. Then all rats were exposed to myocardial I/R. Hormone, vascular endothelial, and inflammatory related factors were detected before and after I/R, while cardiac injury, cardiac function, myocardial infarct size, and apoptosis were detected after I/R. Results. Levels of neuropeptide Y, vascular endothelial and inflammatory related factors were significantly increased while melatonin was decreased in vehicle-treated SD rats but not in HAR-treated SD rats after SD. In addition, cardiac injury, cardiac dysfunction, myocardial infarct size, and myocardial apoptosis were deteriorated in vehicle-treated SD rats but were ameliorated in HAR-treated SD rats after I/R. Conclusion. HAR not only improved SD-induced hormone disorders, inflammation, and endothelial dysfunction, but also alleviated I/R injury, which supports protective usage in CHD and psychocardiology.

  12. Gadolinium decreases inflammation related to myocardial ischemia and reperfusion injury

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    Nicolosi Alfred C

    2009-12-01

    control and GdCl3 treated rats. Likewise, IL-8 levels increased throughout the 3 hour time period in the Sham group. There was no difference in IL-8 detected in the myocardium after 120 min reperfusion between groups. In contrast, after 120 min reperfusion GdCl3 decreased the myocardial tissue levels of macrophage secreted cytokines, GM-CSF and IL-1. Conclusion GdCl3 treatment prior to ischemia and reperfusion injury decreased circulating monocytes and neutrophils, macrophage secreted cytokines, and leukocyte infiltration into injured myocardium. These results suggest GdCl3 decreased monoctye and neutrophil migration and activation and may be a novel treatment for inflammation during ischemia and reperfusion.

  13. Cardioprotective Effect of the Aqueous Extract of Lavender Flower against Myocardial Ischemia/Reperfusion Injury

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    Dong Wang

    2014-01-01

    Full Text Available This study was conducted to evaluate the cardioprotective property of the aqueous extract of lavender flower (LFAE. The myocardial ischemia/reperfusion (I/R injury of rat was prepared by Langendorff retrograde perfusion technology. The heart was preperfused with K-H solution containing LFAE for 10 min before 20 minutes global ischemia, and then the reperfusion with K-H solution was conducted for 45 min. The left ventricular developed pressure (LVDP and the maximum up/downrate of left ventricular pressure (±dp/dtmax were recorded by physiological recorder as the myocardial function and the myocardial infarct size was detected by TTC staining. Lactate dehydrogenase (LDH and creatine kinase (CK activities in the effluent were measured to determine the myocardial injury degree. The superoxide anion dismutase (SOD and malondialdehyde (MDA in myocardial tissue were detected to determine the oxidative stress degree. The results showed that the pretreatment with LFAE significantly decreased the myocardial infarct size and also decreased the LDH, CK activities, and MDA level, while it increased the LVDP, ±dp/dtmax, SOD activities, and the coronary artery flow. Our findings indicated that LFAE could provide protection for heart against the I/R injury which may be related to the improvement of myocardial oxidative stress states.

  14. MG132 Inhibits Myocardial Ischemia-reperfusion Injury by Regulating Apoptotic Pathway

    Institute of Scientific and Technical Information of China (English)

    Dai Cuilian; Luo Kailiang; Chen Zhangrong

    2007-01-01

    Objectives To administrated proteasome inhibitor-MG-132 prior to reperfusion in rat myocardial ischemia-reperfusion model to determine whether MG-132 could reduce myocytic apoptosis. Methods and results MG-132 (0.75 mg/kg in 2 ml DMSO) injection 5 min prior to reperfusion resulted significant reduction of myocardial reperfusion injury. This effect was accompanied by reduced polymorphonuclear neutrophils(PMN) infiltration in myocardial region surrounding the myocardial infarct, reduced apoptosis in cardiac myocytes, reduced NF-κB activation, as determined by electron microscopy, histology, immunohistochemistry, the terminal deoxynucleotidyl transferase-mediated nick endlabeling (TUNEL) method, reverse transcription-polymerase chain reaction. Functional effects of MG-132 on PMN accumulation, activation of nuclear factor kappa B(p65 mRNA and protein levels ), and apoptosis were characterized in rat myocardial tissue. MG132 time-dependently inhibited myocardial p65 mRNA expression and reduced myocardial apoptotic index (AI) after reperfusion for 2 h, 6 h and 24 h ( P<0.01 ). Moreover, MG-132 time-dependently decreased Bax protein levels, while increased Bcl-2 protein levels in ischemic and reperfused myocardium ( P<0.05 ), its effect peaked after reperfusion for 24 h. Conclusions Our results demonstrate that MG-132 reduced myocardial reperfusion injury by inhibiting myosytic apoptotic cell death and blocking activation of NF-κB, down-regulating Bax expression and up-regulating Bcl-2 expression as well as elevating Bcl-2/Bax ratio.

  15. Short-term mortality in patients with myocardial injury and myocardial infarction type 1 and type 2

    DEFF Research Database (Denmark)

    Sarkisian, Laura; Saaby, L.; Poulsen, T. S.

    2015-01-01

    Introduction: Troponin elevations occur in a myriad of clinical conditions other than myocardial infarction (MI) and imply a poor prognosis. So far, data comparing the short-term outcome in patients with myocardial injury vs. patients with type 1 or type 2 MI are not available Methods: Over a 1......-year period we prospectively studied hospitalized patients having cardiac troponin I (cTnI) measured on clinical indication. The diagnosis of type 1 and type 2 MI was according to the universal definition involving a rising and/or falling pattern of cTnI values above the decision limit of 30 ng/L. c......TnI elevations above this limit in patients without overt myocardial ischemia were defined as myocardial injury. A 1-month follow-up was done with mortality as endpoint Results: The study covered 1577 consecutive patients with cTnI values >30 ng/L, of whom 360 had a type 1 MI, 119 a type 2 MI and 1089 had...

  16. Molecular Characterization of Reactive Oxygen Species in Myocardial Ischemia-Reperfusion Injury

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    Tingyang Zhou

    2015-01-01

    Full Text Available Myocardial ischemia-reperfusion (I/R injury is experienced by individuals suffering from cardiovascular diseases such as coronary heart diseases and subsequently undergoing reperfusion treatments in order to manage the conditions. The occlusion of blood flow to the tissue, termed ischemia, can be especially detrimental to the heart due to its high energy demand. Several cellular alterations have been observed upon the onset of ischemia. The danger created by cardiac ischemia is somewhat paradoxical in that a return of blood to the tissue can result in further damage. Reactive oxygen species (ROS have been studied intensively to reveal their role in myocardial I/R injury. Under normal conditions, ROS function as a mediator in many cell signaling pathways. However, stressful environments significantly induce the generation of ROS which causes the level to exceed body’s antioxidant defense system. Such altered redox homeostasis is implicated in myocardial I/R injury. Despite the detrimental effects from ROS, low levels of ROS have been shown to exert a protective effect in the ischemic preconditioning. In this review, we will summarize the detrimental role of ROS in myocardial I/R injury, the protective mechanism induced by ROS, and potential treatments for ROS-related myocardial injury.

  17. Dephosphorylation of cardiomyocyte Cx43 is associated with myocardial ischemia and reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Zhijuan Cao; Xuan Xu; Linli Que; Qi Chen; Yuehua Li

    2009-01-01

    Objective:Myocardial ischemia/reperfusion(I/R) injury is the leading cause of death in the world. However, the details of the mechanism of its pathophysioiogy are still unknown. The present study was designed to investigate the role of connexin 43(Cx63) in acute models of myocardial I/R injury. Methods: Male C57BL/6 mice were subjected to myocardial ischemia(45 rain) followed by reperfusion(4 hrs) in vivo. The whole operation was monitored using a two-lead ECG. Hearts were harvested and the level of protein was assessed by western blot analysis. Haematoxylin and Eosin(HE) staining was used to detect the extent of neutrophil infiltration. The expression level of IL-6 was detected by ELISA. Results: A murine myocardial I/R injury model was constructed successfully. Phosphorylated Cx43 decreased 83.45% while non-phosphorylated Cx43 increased 1.62- fold in the myocardium after I/R injury. Neutrophil infiltration and the expression of the inflammatory cytokine IL-6 increased in the myocardium following I/R. Conclusion: During myocardial I/R injury, cardiomyocyte Cx43 is dephosphorylated, and this may be associated with an inflammatory response.

  18. Cardiac Dysregulation and Myocardial Injury in a 6-Hydroxydopamine-Induced Rat Model of Sympathetic Denervation.

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    Yue-Hua Jiang

    Full Text Available Cardiac sympathetic denervation is found in various cardiac pathologies; however, its relationship with myocardial injury has not been thoroughly investigated.Twenty-four rats were assigned to the normal control group (NC, sympathectomy control group (SC, and a sympathectomy plus mecobalamin group (SM. Sympathectomy was induced by injection of 6-OHDA, after which, the destruction and distribution of sympathetic and vagal nerve in the left ventricle (LV myocardial tissue were determined by immunofluorescence and ELISA. Heart rate variability (HRV, ECG and echocardiography, and assays for myocardial enzymes in serum before and after sympathectomy were examined. Morphologic changes in the LV by HE staining and transmission electron microscope were used to estimate levels of myocardial injury and concentrations of inflammatory cytokines were used to reflect the inflammatory reaction.Injection of 6-OHDA decreased NE (933.1 ± 179 ng/L for SC vs. 3418.1± 443.6 ng/L for NC, P < 0.01 and increased NGF (479.4± 56.5 ng/mL for SC vs. 315.85 ± 28.6 ng/mL for NC, P < 0.01 concentrations. TH expression was reduced, while ChAT expression showed no change. Sympathectomy caused decreased HRV and abnormal ECG and echocardiography results, and histopathologic examinations showed myocardial injury and increased collagen deposition as well as inflammatory cell infiltration in the cardiac tissue of rats in the SC and SM groups. However, all pathologic changes in the SM group were less severe compared to those in the SC group.Chemical sympathectomy with administration of 6-OHDA caused dysregulation of the cardiac autonomic nervous system and myocardial injuries. Mecobalamin alleviated inflammatory and myocardial damage by protecting myocardial sympathetic nerves.

  19. Diabetic Inhibition of Preconditioning- and Postconditioning-Mediated Myocardial Protection against Ischemia/Reperfusion Injury

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    Xia Yin

    2012-01-01

    Full Text Available Ischemic preconditioning (IPC or postconditioning (Ipost is proved to efficiently prevent ischemia/reperfusion injuries. Mortality of diabetic patients with acute myocardial infarction was found to be 2–6 folds higher than that of non-diabetic patients with same myocardial infarction, which may be in part due to diabetic inhibition of IPC- and Ipost-mediated protective mechanisms. Both IPC- and Ipost-mediated myocardial protection is predominantly mediated by stimulating PI3K/Akt and associated GSK-3β pathway while diabetes-mediated pathogenic effects are found to be mediated by inhibiting PI3K/Akt and associated GSK-3β pathway. Therefore, this review briefly introduced the general features of IPC- and Ipost-mediated myocardial protection and the general pathogenic effects of diabetes on the myocardium. We have collected experimental evidence that indicates the diabetic inhibition of IPC- and Ipost-mediated myocardial protection. Increasing evidence implies that diabetic inhibition of IPC- and Ipost-mediated myocardial protection may be mediated by inhibiting PI3K/Akt and associated GSK-3β pathway. Therefore any strategy to activate PI3K/Akt and associated GSK-3β pathway to release the diabetic inhibition of both IPC and Ipost-mediated myocardial protection may provide the protective effect against ischemia/reperfusion injuries.

  20. Effects of intracoronary melatonin on ischemia-reperfusion injury in ST-elevation myocardial infarction

    DEFF Research Database (Denmark)

    Ekeløf, Sarah V; Halladin, Natalie L; Jensen, Svend E

    2016-01-01

    Acute coronary occlusion is effectively treated by primary percutaneous coronary intervention. However, myocardial ischemia-reperfusion injury is at the moment an unavoidable consequence of the procedure. Oxidative stress is central in the development of ischemia-reperfusion injury. Melatonin......, an endogenous hormone, acts through antioxidant mechanisms and could potentially minimize the myocardial injury. The aim of the experimental study was to examine the cardioprotective effects of melatonin in a porcine closed-chest reperfused infarction model. A total of 20 landrace pigs were randomized...... to a dosage of 200 mg (0.4 mg/mL) melatonin or placebo (saline). The intervention was administered intracoronary and intravenous. Infarct size, area at risk and microvascular obstruction were determined ex vivo by cardiovascular magnetic resonance imaging. Myocardial salvage index was calculated. The plasma...

  1. Gunshot injury of the heart: an unusual cause of acute myocardial infarction.

    Science.gov (United States)

    Bali, Harinder K; Vijayvergiya, Rajesh; Banarjee, Sunip; Kumar, Nikhil

    2003-01-01

    A 30-year-old man had multiple pellet injuries after being shot. An asymptomatic, acute, inferior-wall myocardial infarction was detected on an electrocardiogram at the time of a pre-anesthetic evaluation for eye surgery. A computed tomographic scan of the chest confirmed the presence of an intracardiac foreign body. Coronary angiography showed occlusion of the distal right coronary artery by a pellet. The patient was managed conservatively with aspirin and metoprolol. In conclusion, a single coronary lesion, the absence of other cardiac complications, and a favorable outcome with conservative medical treatment after a gunshot injury contribute to the rarity of this case of myocardial infarction.

  2. Native Magnetic Resonance T1-Mapping Identifies Diffuse Myocardial Injury in Hypothyroidism.

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    Xia Gao

    Full Text Available Hypothyroidism (HT is characterized by thyroid hormone deficiencies, which can lead to diffuse myocardial interstitium lesions in patients with HT. Myocardial longitudinal relaxation time (T1 mapping is a potential diagnostic tool for quantifying diffuse myocardial injury. This study aimed to assess the usefulness of T1 mapping in identifying myocardial involvement in HT, and determine the relationship between T1 values and myocardial function.A cross-sectional study was conducted with 30 untreated HT patients alongside 23 age- and sex-matched healthy controls. All subjects underwent cardiac magnetic resonance (CMR with non-contrast (native T1 mapping using a modified Look-Locker inversion-recovery (MOLLI sequence to assess the native T1 values of myocardium and cardiac function.Native myocardial T1 values were significantly increased in HT patients, especially those with pericardial effusion (p < 0.05, compared with healthy controls. In addition, significantly reduced peak filling rate (PFR and prolonged peak filling time (PFT were obtained (p < 0.05 in HT patients compared with controls. Furthermore, stroke volume (SV and cardiac index (CI were significantly lower in HT patients than controls (all p < 0.05. Interestingly, native T1 values were negatively correlated with free triiodothyronine (FT3, PFR, SV and CI (all p < 0.05.Diffuse myocardial injuries are common in HT patients, and increased T1 values are correlated with FT3 and cardiac function impairment. These findings indicate that T1 mapping might be useful in evaluating myocardial injuries in HT patients.

  3. Two cases in which myocardial injury could be only evaluated by nuclear medicine studies on electric shock patients whose electrocardiogram and myocardial enzyme levels were normal.

    Science.gov (United States)

    Amino, Mari; Yoshioka, Koichiro; Morita, Seiji; Yamagiwa, Takeshi; Otsuka, Hiroyuki; Akieda, Kazuki; Iizuka, Shinichi; Kanda, Shigetaka; Ikari, Yuji; Nasu, Seiji; Hatakeyama, Kenji; Kodama, Itsuo; Inokuchi, Sadaki; Tanabe, Teruhisa

    2009-03-01

    Heart injury due to electric shock is currently diagnosed based on electrocardiogram (ECG) changes or elevated levels of myocardial enzymes or both. However, the rate at which ECG detects abnormalities is very low; thus, the estimated rate of the diagnosis of myocardial damage due to electric shock is lower than the actual rate. The method of nuclear medicine study of the heart is superior with regard to evaluating transient ischemia, such as angina pectoris, in patients whose ECG and myocardial enzyme levels are normal. Therefore, we attempted to diagnose transient myocardial damage in electric shock patients by using nuclear medicine study of the heart.

  4. Pharmacological Attenuation of Myocardial Reperfusion Injury in a Closed-Chest Porcine Model

    DEFF Research Database (Denmark)

    Ekeløf, Sarah; Rosenberg, Jacob; Jensen, Jan Skov;

    2014-01-01

    Myocardial ischemia-reperfusion injury is a clinical challenge in interventional cardiology, and at the moment, no pharmacological agent is universally accepted in the prevention. In order to prevent inappropriate clinical trials, a potential pharmacological agent should be proved reproducibly...... effective in clinically relevant experimental studies before initiation of human studies. The closed-chest porcine model is a promising experimental model of ischemia-reperfusion injury. The purpose of this systematic review was to describe the pharmacological treatments evaluated in the closed...

  5. Protective Effects of L-Malate against Myocardial Ischemia/Reperfusion Injury in Rats

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    Shiao Ding

    2016-01-01

    Full Text Available Objective. To investigate the protective effects of L-malate against myocardial ischemia/reperfusion (I/R injury in rats. Methods. Male Sprague-Dawley rats were randomly assigned to the following groups: sham (sham, an ischemia/reperfusion (I/R model group (model, an DMF pretreated group (DMF, and 5 L-malate pretreated groups (15, 60, 120, 240, or 480 mg/kg, gavage before inducing myocardial ischemia. Plasma LDH, cTn-I, TNF-α, hs-CRP, SOD, and GSH-PX were measured 3 h later I/R. Areas of myocardial infarction were measured; hemodynamic parameters during I/R were recorded. Hearts were harvested and Western blot was used to quantify Nrf2, Keap1, HO-1, and NQO-1 expression in the myocardium. Results. L-malate significantly reduced LDH and cTn-I release, reduced myocardial infarct size, inhibited expression of inflammatory cytokines, and partially preserved heart function, as well as increasing antioxidant activity after myocardial I/R injury. Western blot confirmed that L-malate reduced Kelch-like ECH-associated protein 1 in ischemic myocardial tissue, upregulated expression of Nrf2 and Nrf2 nuclear translocation, and increased expression of heme oxygenase-1 and NAD(PH:quinone oxidoreductase 1, which are major targets of Nrf2. Conclusions. L-malate may protect against myocardial I/R injury in rats and this may be associated with activation of the Nrf2/Keap1 antioxidant pathway.

  6. Predictors of myocardial injury in patients with acute upper gastrointestinal bleeding

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    El-Sayed M Farag

    2014-03-01

    The most significant predictors for myocardial injury in patients with UGIB in descending order were hypertension, cigarette smoking, liver cirrhosis, body mass index > 25 kg/m2, and C-reactive protein level  > 5 mg/dl.

  7. NADPH oxidase inhibitor apocynin attenuates ischemia/reperfusion induced myocardial injury in rats

    Institute of Scientific and Technical Information of China (English)

    罗秀菊

    2013-01-01

    Objective To explore the role of NADPH oxidase inhibitor apocynin on ischemia/reperfusion(I/R)-induced myocardial injury. Methods Male SD rat hearts were divided into the normal control group; sham group;I/R group(1 h ischemia followed by 3 h reperfusion); I/R+ apocynin group(50 mg/kg,administrated at 30 min

  8. Free triiodothyronine level indicates the degree of myocardial injury in patients with acute ST-elevation myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    WANG Wen-yao; TANG Yi-da; YANG Min; CUI Cheng; MU Mu; QIAN Jie; YANG Yue-jin

    2013-01-01

    Background Previous studies have suggested that hypothyroidism correlated with coronary heart diseases (CHD) mortality in long-term cohort,but whether the thyroid function status is associated with myocardial injury in acute ST-elevation myocardial infarction (STEMI) has not been investigated sufficiently.Methods Five hundred and eighty-two hospitalized patients from January 2010 to December 2011,with the diagnosis of STEMI,were enrolled in this study.All patients underwent testing for thyroid function status,cardiac troponin I (cTnl),cardiac enzymes,C-reactive protein (CRP).We investigated the association between thyroid hormone levels and cardiac markers (creatine kinase-MB and cTnl),and thus evaluated the potential role of thyroid function status in predicting the myocardial injury.Results There were 76 patients (13.06%)who had hypothyroidism including low-T3-syndrome (34 patients,5.84%),subclinical hypothyroidism (28 patients,4.81%) and clinical hypothyroidism (14 patients,2.41%).After adjusting for conventional risk factors (age,gender,smoking,diabetes mellitus,dyslipidemia,hypertension),free triiodothyronine (FT3) was significantly and negatively correlated with log-CKMB (r=-0.244,P <0.001) and log-cTnl (r=0.290,P <0.001),indicating that the lower thyroid hormone level correlates with the severer cardiac injury in STEMI patients.FT3 also had a moderate negative correlation with CRP (r=-0.475,P <0.001),which might indicate that hypothyroidism may activate the inflammation response.No significant correlation was found between other thyroid parameters (TSH,FT4) and cardiac markers.Conclusions As the lower FT3 level correlates with higher level of cardiac markers and lower left ventricular ejection fraction (LVEF),the hypothyroidism may be a predictor for myocardial injury in STEMI.And these results may warrant further study to investigate whether reversing the hypothyroidism could benefit the STEMI patients.

  9. Predictive Risk Factors for Upper Gastrointestinal Bleeding with Simultaneous Myocardial Injury

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    I-Chen Wu

    2007-01-01

    Full Text Available The aims of this study were to: (1 evaluate the epidemiology of simultaneous upper gastrointestinal bleeding (UGIB and myocardial injury using parameters including troponin I (TnI; and (2 investigate the predictive risk factors of this syndrome. One hundred and fifty-five patients (101 men, 54 women; mean age, 64.7 ± 10.4 years; range, 38–94 years at the emergency department (ED with the major diagnosis of UGIB were included. They underwent serial electrocardiography (ECG and cardiac enzyme follow-up. Emergent gastroendoscopy was performed within 24 hours in most patients except for those who refused or were contraindicated. Mild myocardial injury was defined as the presence of any of the following: typical ST-T change on ECG, elevated creatine kinase-MB (CK-MB > 12U/L, or TnI > 0.2ng/dL. Moderate myocardial injury was defined as the presence of any two of the previously mentioned conditions. In total, 51 (32.9% and 12 (7.74% patients developed mild and moderate myocardial injuries, respectively. Myocardial injury was more common among patients with variceal bleeding (20/25 = 80.0% than those with ulcer bleeding (23/112 = 20.5%. It could partially be attributed to a higher baseline TnI level in cirrhotic patients. After adjusting for significant risk factors revealed by the univariate analysis, UGIB patients with a history of liver cirrhosis and more than three cardiac risk factors comprised a high-risk group for simultaneously developing myocardial injury. Other factors including age, gender, the color of nasogastric tube irrigation fluid, history of nonsteroidal anti-inflammatory drug use, vasopressin or terlipressin administration, vital signs, and creatinine recorded at the ED were not significant predictors. Those who developed myocardial injury had a longer hospital stay (mean duration, 8.73 ± 6.94 vs. 6.34 ± 2.66 days; p = 0.03 and required transfusion of more units of packed erythrocytes.

  10. Effect and mechanism of salvianolic acid B on the myocardial ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Ling Xue; Zhen Wu; Xiao-Ping Ji; Xia-Qing Gao; Yan-Hua Guo

    2014-01-01

    Objective: To investigate the effect of salvianolic acid B on rats with myocardial ischemia-reperfusion injury. Methods: SD rats were randomly divided into five groups (n=10 in each group): A sham operation group, B ischemic reperfusion group model group, C low dose salvianolic acid B group, D median dose salvianolic acid B group, E high dose salvianolic acid B group. One hour after establishment of the myocardial ischemia-reperfusion model, the concentration and the apoptotic index of the plasma level of myocardial enzymes (CTnⅠ, CK-MB), SOD, MDA, NO, ET were measured. Heart tissues were obtained and micro-structural changes were observed. Results: Compared the model group, the plasma CTnⅠ, CK-MB, MDA and ET contents were significantly increased, NO, T-SOD contents were decreased in the treatment group (group C, D, and E) (P<0.05); compared with group E, the plasma CTnⅠ, CK-MB, MDA and ET levels were increased, the NO, T-SOD levels were decreased in groups C and D (P<0.05). Infarct size was significantly reduced, and the myocardial ultrastructural changes were improved significantly in treatment group. Conclusions: Salvianolic acid B has a significant protective effect on myocardial ischemia-reperfusion injury. It can alleviate oxidative stress, reduce calcium overload, improve endothelial function and so on.

  11. Cardioprotective Effect of Electroacupuncture Pretreatment on Myocardial Ischemia/Reperfusion Injury via Antiapoptotic Signaling

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    Sheng-feng Lu

    2016-01-01

    Full Text Available Objectives. Our previous study has used RNA-seq technology to show that apoptotic molecules were involved in the myocardial protection of electroacupuncture pretreatment (EAP on the ischemia/reperfusion (I/R animal model. Therefore, this study was designed to investigate how EAP protects myocardium against myocardial I/R injury through antiapoptotic mechanism. Methods. By using rats with myocardial I/R, we ligated the left anterior descending artery (LAD for 30 minutes followed by 4 hr of reperfusion after EAP at the Neiguan (PC6 acupoint for 12 days; we employed arrhythmia scores, serum myocardial enzymes, and cardiac troponin T (cTnT to evaluate the cardioprotective effect. Heart tissues were harvested for western blot analyses for the expressions of pro- and antiapoptotic signaling molecules. Results. Our preliminary findings showed that EAP increased the survival of the animals along with declined arrhythmia scores and decreased CK, LDH, CK-Mb, and cTnT levels. Further analyses with the heart tissues detected reduced myocardial fiber damage, decreased number of apoptotic cells and the protein expressions of Cyt c and cleaved caspase 3, and the elevated level of Endo G and AIF after EAP intervention. At the same time, the protein expressions of antiapoptotic molecules, including Xiap, BclxL, and Bcl2, were obviously increased. Conclusions. The present study suggested that EAP protected the myocardium from I/R injury at least partially through the activation of endogenous antiapoptotic signaling.

  12. Histamine deficiency exacerbates myocardial injury in acute myocardial infarction through impaired macrophage infiltration and increased cardiomyocyte apoptosis.

    Science.gov (United States)

    Deng, Long; Hong, Tao; Lin, Jinyi; Ding, Suling; Huang, Zheyong; Chen, Jinmiao; Jia, Jianguo; Zou, Yunzeng; Wang, Timothy C; Yang, Xiangdong; Ge, Junbo

    2015-08-17

    Histamine is a biogenic amine that is widely distributed and has multiple functions, but the role it plays in acute myocardial infarction (AMI) remains unclear. In this study, we investigated the origin and contribution of endogenous histamine to AMI. Histidine decarboxylase (HDC) is the unique enzyme responsible for histamine generation. Using HDC-EGFP bacterial artificial chromosome (BAC) transgenic mice in which EGFP expression is controlled by the HDC promoter, we identified HDC expression primarily in CD11b(+)Gr-1(+) immature myeloid cells (IMCs) that markedly increase in the early stages of AMI. Deficiency of histamine in HDC knockout mice (HDC(-/-)) reduced cardiac function and exacerbated the injury of infarcted heart. Furthermore, administering either an H1 receptor antagonist (pyrilamine) or an H2 receptor antagonist (cimetidine) demonstrated a protective effect of histamine against myocardial injury. The results of in vivo and in vitro assays showed that histamine deficiency promotes the apoptosis of cardiomyocytes and inhibits macrophage infiltration. In conclusion, CD11b(+)Gr-1(+) IMCs are the predominant HDC-expressing sites in AMI, and histamine plays a protective role in the process of AMI through inhibition of cardiomyocyte apoptosis and facilitation of macrophage infiltration.

  13. Effect of Curcuma longa and Ocimum sanctum on myocardial apoptosis in experimentally induced myocardial ischemic-reperfusion injury

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    Mohanty, Ipseeta; Arya, Dharamvir Singh; Gupta, Suresh Kumar

    2006-01-01

    Background In the present investigation, the effect of Curcuma longa (Cl) and Ocimum sanctum (Os) on myocardial apoptosis and cardiac function was studied in an ischemia and reperfusion (I-R) model of myocardial injury. Methods Wistar albino rats were divided into four groups and orally fed saline once daily (sham, control IR) or Cl (100 mg/kg; Cl-IR) or Os (75 mg/kg; Os-IR) respectively for 1 month. On the 31st day, in the rats of the control IR, Cl-IR and Os-IR groups LAD occlusion was undertaken for 45 min, and reperfusion was allowed for 1 h. The hemodynamic parameters{mean arterial pressure (MAP), heart rate (HR), left ventricular end-diastolic pressure (LVEDP), left ventricular peak positive (+) LVdP/dt (rate of pressure development) and negative (-) LVdP/dt (rate of pressure decline)} were monitored at pre-set points throughout the experimental duration and subsequently, the animals were sacrificed for immunohistopathological (Bax, Bcl-2 protein expression & TUNEL positivity) and histopathological studies. Results Chronic treatment with Cl significantly reduced TUNEL positivity (p < 0.05), Bax protein (p < 0.001) and upregulated Bcl-2 (p < 0.001) expression in comparison to control IR group. In addition, Cl demonstrated mitigating effects on several myocardial injury induced hemodynamic {(+)LVdP/dt, (-) LVdP/dt & LVEDP} and histopathological perturbations. Chronic Os treatment resulted in modest modulation of the hemodynamic alterations (MAP, LVEDP) but failed to demonstrate any significant antiapoptotic effects and prevent the histopathological alterations as compared to control IR group. Conclusion In the present study, significant cardioprotection and functional recovery demonstrated by Cl may be attributed to its anti-apoptotic property. In contrast to Os, Cl may attenuate cell death due to apoptosis and prevent the impairment of cardiac performance. PMID:16504000

  14. Protective Effects of Chinese Traditional Medicine Buyang Huanwu Decoction on Myocardial Injury

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    Guangde Yang

    2011-01-01

    Full Text Available Many clinical studies have reported that Buyang Huanwu Decoction (BYHWD has a protective effect on ischemic heart disease (IHD. In the present study, the protective effect of BYHWD on myocardial ischemia was investigated. Different doses of BYHWD and Compound Danshen Dropping Pills (CDDP were lavaged to rats, respectively, isoproterenol (ISO was intraperitoneally injected in to all animals to induce myocardial ischemia except the control group. Electrocardiogram (ECG of each animal was recorded; activities of lactate dehydrogenase (LDH, creatine kinase (CK and aspartate aminotransferase (AST in serum were detected. As the results of ECG showed, pre-treatment with BYHWD inhibited ischemic myocardial injury, and the activities of LDH, CK and AST were lower than those in the myocardial ischemia model group, which suggests that BYHWD rescues the myocardium from ischemia status. To research the potential mechanism, the level of nitric oxide (NO, nitric oxide syntheses (NOS and inducible nitric oxide syntheses (iNOS, the expression of iNOS and ligand of cluster of differentiation 40 (CD40L were detected. The results revealed that BYHWD significantly decreased the level of NO, NOS and iNOS in serum. Moreover, BYHWD decreased the expression of iNOS and CD40L in myocardial tissues. These results indicate that the protective effect of BYHWD on myocardial ischemia and mechanism are associated with inhibition of iNOS and CD40L expression.

  15. The effect of levosimendan on myocardial ischemia–reperfusion injury in streptozotocin-induced diabetic rats

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    Kiraz, Hasan Ali; Poyraz, Fatih; Kip, Gülay; Erdem, Özlem; Alkan, Metin; Arslan, Mustafa; Özer, Abdullah; Şivgin, Volkan; Çomu, Faruk Metin

    2015-01-01

    Objective Ischemia/reperfusion (I/R) injury is an important cause of myocardial damage by means of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine the potential cardio protective effects of levosimendan in a diabetic rat model of myocardial I/R injury. Methods A total of 18 streptozotocin-induced diabetic Wistar Albino rats (55 mg/kg) were randomly divided into three equal groups as follows: the diabetic I/R group (DIR) in which myocardial I/R was induced following left thoracotomy, by ligating the left anterior descending coronary artery for 60 min, followed by 2 h of reperfusion; the diabetic I/R levosimendan group (DIRL), which underwent I/R by the same method while taking levosimendan intraperitoneal 12 µg kg−1; and the diabetic control group (DC) which underwent sham operations without tightening of the coronary sutures. As a control group (C), six healthy age-matched Wistar Albino rats underwent sham operations similar to the DC group. Two hours after the operation, the rats were sacrificed and the myocardial tissue samples were examined by light microscopy for evidence of myonecrosis and inflammatory cell infiltration. Results Myonecrosis findings were significantly different among groups (p=0.008). Myonecrosis was more pronounced in the DIR group compared with the C, DC, and DIRL groups (p=0.001, p=0.007 and p=0.037, respectively). Similarly, the degree of inflammatory cell infiltration showed significant difference among groups (p<0.0001). Compared with C, DC, and DIRL groups, the inflammatory cell infiltration was significantly higher among the DIR group (p<0.0001, p<0.0001, and p=0.020, respectively). Also, myocardial tissue edema was significantly different among groups (p=0.006). The light microscopic myocardial tissue edema levels were significantly higher in the DIR group than the C, DC, and DIRL groups (p=0.001, p=0.037, and p=0.014, respectively). Conclusion Taken together, our data indicate that

  16. The effect of levosimendan on myocardial ischemia–reperfusion injury in streptozotocin-induced diabetic rats

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    Hasan Ali Kiraz

    2015-12-01

    Full Text Available Objective: Ischemia/reperfusion (I/R injury is an important cause of myocardial damage by means of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine the potential cardio protective effects of levosimendan in a diabetic rat model of myocardial I/R injury. Methods: A total of 18 streptozotocin-induced diabetic Wistar Albino rats (55 mg/kg were randomly divided into three equal groups as follows: the diabetic I/R group (DIR in which myocardial I/R was induced following left thoracotomy, by ligating the left anterior descending coronary artery for 60 min, followed by 2 h of reperfusion; the diabetic I/R levosimendan group (DIRL, which underwent I/R by the same method while taking levosimendan intraperitoneal 12 µg kg−1; and the diabetic control group (DC which underwent sham operations without tightening of the coronary sutures. As a control group (C, six healthy age-matched Wistar Albino rats underwent sham operations similar to the DC group. Two hours after the operation, the rats were sacrificed and the myocardial tissue samples were examined by light microscopy for evidence of myonecrosis and inflammatory cell infiltration. Results: Myonecrosis findings were significantly different among groups (p=0.008. Myonecrosis was more pronounced in the DIR group compared with the C, DC, and DIRL groups (p=0.001, p=0.007 and p=0.037, respectively. Similarly, the degree of inflammatory cell infiltration showed significant difference among groups (p<0.0001. Compared with C, DC, and DIRL groups, the inflammatory cell infiltration was significantly higher among the DIR group (p<0.0001, p<0.0001, and p=0.020, respectively. Also, myocardial tissue edema was significantly different among groups (p=0.006. The light microscopic myocardial tissue edema levels were significantly higher in the DIR group than the C, DC, and DIRL groups (p=0.001, p=0.037, and p=0.014, respectively. Conclusion: Taken together, our data

  17. The diagnostic value of both troponin T and creatinine kinase isoenzyme (CK-MB in detecting combined renal and myocardial injuries in asphyxiated infants.

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    Wilson E Sadoh

    Full Text Available Troponin T (cTnT and Creatinine Kinase Isoenzyme (CK-MB are both markers of myocardial injuries. However, CK-MB is also elevated in acute kidney injury.The diagnostic value of both cTnT and cardiac CK-MB in combined myocardial and acute kidney injuries (AKI in asphyxiated neonates was evaluated.40 asphyxiated infants and 40 non-asphyxiated controls were consecutively recruited. Serum levels of cTnT, CK-MB and creatinine were measured. Myocardial injury and AKI were defined as cTnT >95th percentile of the control and serum creatinine >1.0 mg/dl respectively.Of the 40 subjects, 9 (22.50%, 8 (20.00% and 4 (10.00% had myocardial injury, AKI and combined AKI and myocardial injuries respectively. The mean cTnT and CK-MB values were highest in infants with combined AKI and myocardial injuries. The Mean cTnT in infants with AKI, myocardial injury and combined AKI and myocardial injuries were 0.010±0.0007 ng/ml, 0.067±0.040 ng/ml and 0.084±0.067 ng/ml respectively, p = 0.006. The mean CK-MB in infants with AKI, myocardial injury and combined AKI and myocardial injuries were 2.78±0.22 ng/ml, 1.28±0.11 ng/ml and 4.58±0.52 ng/ml respectively, p = <0.0001.In severe perinatal asphyxia, renal and myocardial injuries could co-exist. Elevated cTnT signifies the presence of myocardial injury. Elevated CK-MB indicates either myocardial injury, AKI or both. Therefore renal injury should be excluded in asphyxiated infants with elevated CK-MB.

  18. [Correlation between insulin resistance and myocardial injury in critically ill children].

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    Jiang, Feng; Ma, Xiang-Ping; Muzhapaer, Duolikun

    2012-02-01

    To study the relationship between insulin resistance and myocardial injury in children with critical diseases in light of the fact that such children usually suffer from noticeable insulin resistance and myocardial injury. Sixty-three children with critical diseases who were admitted between March 2010 and June 2011 were enrolled to comprise a case group. Fasting blood glucose, serum insulin, myocardial enzyme, and troponin I (CTnI) levels were measured. The insulin resistance index (HOMA-IR) was calculated. The children were classified into two groups: insulin resistance (HOMA-IR>1.0; n=30) and non-insulin resistance (HOMA-IR≤1.0; n=33). Thirty healthy children served as the control group. HOMA-IR, lactate dehydrogenase (LDH), aspartate aminotransferaseaspartate transaminase (AST), creatine kinase (CK), isoenzymes of creating kinase (CK-MB), α-hydroxybuty rate dehydrogenase (α-HBDH) and CTnI in the insulin resistance group were higher than those in the non-insulin resistance and the control groups (all Presistance group also showed obviously higher levels in terms of LDH, AST, CK, CK-MB, α-HBDH, and CTnI than the control group (Presistance group, there exists a positive correlation between HOMA-IR and such indicators as LDH, CK, CK-MB, AST, α-HBDH and CTnI (r=0.697, 0.739, 0.781, 0.642, 0.381, 0.792 respectively; all Presistance makes myocardial injury more serious; HOMA-IR can serve as a forecast indicator for the degree of myocardial injury.

  19. Blockage of transient receptor potential vanilloid 4 alleviates myocardial ischemia/reperfusion injury in mice

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    Dong, Qian; Li, Jing; Wu, Qiong-feng; Zhao, Ning; Qian, Cheng; Ding, Dan; Wang, Bin-bin; Chen, Lei; Guo, Ke-Fang; Fu, Dehao; Han, Bing; Liao, Yu-Hua; Du, Yi-Mei

    2017-01-01

    Transient receptor potential vanilloid 4 (TRPV4) is a Ca2+-permeable nonselective cation channel and can be activated during ischemia/reperfusion (I/R). This study tested whether blockade of TRPV4 can alleviate myocardial I/R injury in mice. TRPV4 expression began to increase at 1 h, reached statistically at 4 h, and peaked at 24–72 h. Treatment with the selective TRPV4 antagonist HC-067047 or TRPV4 knockout markedly ameliorated myocardial I/R injury as demonstrated by reduced infarct size, decreased troponin T levels and improved cardiac function at 24 h after reperfusion. Importantly, the therapeutic window for HC-067047 lasts for at least 12 h following reperfusion. Furthermore, treatment with HC-067047 reduced apoptosis, as evidenced by the decrease in TUNEL-positive myocytes, Bax/Bcl-2 ratio, and caspase-3 activation. Meanwhile, treatment with HC-067047 attenuated the decrease in the activation of reperfusion injury salvage kinase (RISK) pathway (phosphorylation of Akt, ERK1/2, and GSK-3β), while the activation of survival activating factor enhancement (SAFE) pathway (phosphorylation of STAT3) remained unchanged. In addition, the anti-apoptotic effects of HC-067047 were abolished by the RISK pathway inhibitors. We conclude that blockade of TRPV4 reduces apoptosis via the activation of RISK pathway, and therefore might be a promising strategy to prevent myocardial I/R injury. PMID:28205608

  20. Intracoronary electrocardiogram during alcohol septal ablation for hypertrophic obstructive cardiomyopathy predicts myocardial injury size.

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    Meng, Jing; Qu, Xiaolong; Huang, Haiyun; Zhang, Shanwen; Zhao, Weibo; He, Guoxiang; Song, Zhiyuan; Hu, Houyuan

    2016-01-01

    Alcohol septal ablation (ASA) has been used widely to treat patients with hypertrophic obstructive cardiomyopathy (HOCM). During the routine ASA procedure, it is difficult to detect the septal injury in real-time. The aim of the present study is to assess myocardial injury during ASA by recording intracoronary electrocardiogram (IC-ECG). From 2012 to 2015, 31 HOCM patients were treated with ASA, and IC-ECG was recorded in 21 patients successfully before and after ethanol injection. The elevation of ST-segment on IC-ECG after ethanol injection was expressed as its ratio to the level before injection or the absolute increasing value. Blood samples were collected before and after ASA for measuring changes in cardiac biomarkers. The ratio value of ST-segment elevation was positively correlated with both the amount of ethanol injected (r = 0.645, P = 0.001) and the myocardial injury size (creatine kinase-MB area under the curve (AUC) of CK-MB) (r = 0.466, P = 0.017). The absolute increment of ST-segment was also positively associated with both the amount of ethanol (r = 0.665, P = 0.001) and AUC of CK-MB (0.685, P = 0.001). However, there was no statistical correlation between the reduction of left ventricular outflow tract gradient and ST-segment elevation. Additionally no severe ASA procedure-related complications were observed in our patients. In conclusion, myocardial injury induced by ethanol injection can be assessed immediately by ST-segment elevation on IC-ECG. This study is the first to show that IC-ECG is a useful method for predicting myocardial injury during ASA in real-time.

  1. Effects and Mechanisms of Chinese Herbal Medicine in Ameliorating Myocardial Ischemia-Reperfusion Injury

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    Qing Liu

    2013-01-01

    Full Text Available Myocardial ischemia-reperfusion (MIR injury is a major contributor to the morbidity and mortality associated with coronary artery disease, which accounts for approximately 450,000 deaths a year in the United States alone. Chinese herbal medicine, especially combined herbal formulations, has been widely used in traditional Chinese medicine for the treatment of myocardial infarction for hundreds of years. While the efficacy of Chinese herbal medicine is well documented, the underlying molecular mechanisms remain elusive. In this review, we highlight recent studies which are focused on elucidating the cellular and molecular mechanisms using extracted compounds, single herbs, or herbal formulations in experimental settings. These studies represent recent efforts to bridge the gap between the enigma of ancient Chinese herbal medicine and the concepts of modern cell and molecular biology in the treatment of myocardial infarction.

  2. Magnetic resonance imaging of myocardial injury and ventricular torsion after marathon running.

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    Hanssen, Henner; Keithahn, Alexandra; Hertel, Gernot; Drexel, Verena; Stern, Heiko; Schuster, Tibor; Lorang, Dan; Beer, Ambros J; Schmidt-Trucksäss, Arno; Nickel, Thomas; Weis, Michael; Botnar, Rene; Schwaiger, Markus; Halle, Martin

    2011-02-01

    Recent reports provide indirect evidence of myocardial injury and ventricular dysfunction after prolonged exercise. However, existing data is conflicting and lacks direct verification of functional myocardial alterations by CMR [cardiac MR (magnetic resonance)]. The present study sought to examine structural myocardial damage and modification of LV (left ventricular) wall motion by CMR imaging directly after a marathon. Analysis of cTnT (cardiac troponin T) and NT-proBNP (N-terminal pro-brain natriuretic peptide) serum levels, echocardiography [pulsed-wave and TD (tissue Doppler)] and CMR were performed before and after amateur marathon races in 28 healthy males aged 41 ± 5 years. CMR included LGE (late gadolinium enhancement) and myocardial tagging to assess myocardial injury and ventricular motion patterns. Echocardiography indicated alterations of diastolic filling [decrease in E/A (early transmitral diastolic filling velocity/late transmitral diastolic filling velocity) ratio and E' (tissue Doppler early transmitral diastolic filling velocity)] postmarathon. All participants had a significant increase in NT-proBNP and/or cTnT levels. However, we found no evidence of LV LGE. MR tagging demonstrated unaltered radial shortening, circumferential and longitudinal strain. Myocardial rotation analysis, however, revealed an increase of maximal torsion by 18.3% (13.1 ± 3.8 to 15.5 ± 3.6 °; P=0.002) and maximal torsion velocity by 35% (6.8 ± 1.6 to 9.2 ± 2.5 °·s-1; Pincreased by 1.23 ± 0.33 °·s-1 after marathon (Pheart rate, whereas peak untwist rate showed no relevant changes. Although marathon running leads to a transient increase of cardiac biomarkers, no detectable myocardial necrosis was observed as evidenced by LGE MRI (MR imaging). Endurance exercise induces an augmented systolic wringing motion of the myocardium and increased diastolic filling velocities. The stress of marathon running seems to be better described as a burden of myocardial

  3. Glaucocalyxin A Ameliorates Myocardial Ischemia-Reperfusion Injury in Mice by Suppression of Microvascular Thrombosis

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    Liu, Xiaohui; Xu, Dongzhou; Wang, Yuxin; Chen, Ting; Wang, Qi; Zhang, Jian; You, Tao; Zhu, Li

    2016-01-01

    Background The aim of this study was to evaluate the cardio-protective roles of glaucocalyxin A (GLA) in myocardial ischemia-reperfusion injury and to explore the underlying mechanism. Material/Methods Myocardial ischemia-reperfusion in wild-type C57BL/6J mice was induced by transient ligation of the left anterior descending artery. GLA or vehicle (solvent) was administrated intraperitoneally to the mice before reperfusion started. After 24 h of myocardial reperfusion, ischemic size was revealed by Evans blue/TTC staining. Cardiac function was evaluated by echocardiography and microvascular thrombosis was assessed by immunofluorescence staining of affected heart tissue. We also measured the phosphorylation of AKT, ERK, P-GSK-3β, and cleaved caspase 3 in the myocardium. Results Compared to the solvent-treated control group, GLA administration significantly reduced infarct size (GLA 13.85±2.08% vs. Control 18.95±0.97%, p<0.05) and improved left ventricular ejection fraction (LVEF) (GLA 53.13±1.11% vs. Control 49.99±1.25%, p<0.05) and left ventricular fractional shortening (LVFS) (28.34±0.71% vs. Control 25.11±0.74%, p<0.05) in mice subjected to myocardial ischemia-reperfusion. GLA also attenuated microvascular thrombosis (P<0.05) and increased the phosphorylation of pro-survival kinase AKT (P<0.05) and GSK-3β (P<0.05) in the myocardium upon reperfusion injury. Conclusions Administration of GLA before reperfusion ameliorates myocardial ischemia-reperfusion injury in mice. The cardio-protective roles of GLA may be mediated through the attenuation of microvascular thrombosis. PMID:27716735

  4. High Sensitivity Troponin T as a Marker of Silent Myocardial Injury in Diabetics

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    Priyanka Datta

    2014-04-01

    Full Text Available Introduction: The new high sensitivity (hs troponin T is speci c biomarkers of myocardial necrosis. It has signi cant bene ts for early recognition of acute myocardial infarction. CK-MB in serum is an important marker in diagnosis of myocardial ischemia. Aim and objective: We aimed to analyse and compare the relationship between glycated haemoglobin levels and hs troponin T, CK-MB in chronic hyperglycaemic patients as a marker of silent micro infarcts. Method and materials: hs Troponin T and CK-MB levels were measured using ECLIA and glycated haemoglobin by using HPLC method by variant turbo II. We grouped 119 chronic diabetic aged 30 - 70yrs in three categories according to HbA1c level Group A 8 %. Diabetic patients with cardiovascular disorder, renal failure, sepsis, skeletal muscle disorder and acute cholecystitis were excluded. Results: There was a 4 fold increase in values of hsTrop T in group II while 9.4 fold for group III in comparison to group I. CK-MB was elevated by 2.7 fold in group II and 3.11 in group III in comparison to group I. Conclusion: The prevalence of detectable hs-cTnT was increased in diabetic population and found speci c than CK-MB to diagnose minimal myocardial cell injury. Troponin T levels can be used to detect early and minimal myocardial cell injury even in the presence of normal CK-MB. These data raise the possibility that hs Troponin T can be used as a predictor of minimal cardiac injury and micro infract in diabetic patients before symptoms manifest.

  5. Molecular and cellular mechanisms of cigarette smoke-induced myocardial injury: prevention by vitamin C.

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    Archita Das

    Full Text Available BACKGROUND: Cardiovascular disease (CVD remains one of the major killers in modern society. One strong risk factor of CVD is cigarette smoking that causes myocardial injury and leads to the genesis of pathological cardiovascular events. However, the exact toxic component(s of cigarette smoke (CS and its molecular and cellular mechanisms for causing myocardial injury leading to heart damage and its prevention are largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using a guinea pig model, here we show that chronic exposure to CS produces myocardial injury that is prevented by vitamin C. Male guinea pigs were fed either vitamin C-deficient (0.5 mg/day or vitamin C-sufficient (15 mg/day diet and subjected to CS exposure from 5 Kentucky Research cigarettes (3R4F/day (6 days/week in a smoke chamber up to 8 weeks. Pair-fed sham controls were subjected to air exposure instead of CS exposure under similar conditions. Myocardial injury was produced in CS-exposed marginal vitamin C-deficient guinea pigs as evidenced by release of cardiac Troponin-T and I in the serum, oxidative stress, inflammation, apoptosis, thrombosis and collagen deposition in the myocardium. Treatment of rat cardiomyocyte cells (H9c2 in vitro and guinea pigs in vivo with p-benzoquinone (p-BQ in amounts derived from CS revealed that p-BQ was a major factor responsible for CS-induced myocardial damage. A moderately large dose of vitamin C (15 mg/day prevented CS/p-BQ-induced myocardial injury. Population based studies indicated that plasma vitamin C levels of smokers without disease were significantly lower (p = 0,0000 than that of non-smokers. Vitamin C levels of CS-related cardiovascular patients were further lower (p = 0.0000 than that of smokers without disease. CONCLUSIONS/SIGNIFICANCE: The results indicate that dietary supplementation of vitamin C may be a novel and simple therapy for the prevention of pathological cardiovascular events in habitual smokers.

  6. The nuclear melatonin receptor RORα is a novel endogenous defender against myocardial ischemia/reperfusion injury.

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    He, Ben; Zhao, Yichao; Xu, Longwei; Gao, Lingchen; Su, Yuanyuan; Lin, Nan; Pu, Jun

    2016-04-01

    Circadian rhythm disruption or decrease in levels of circadian hormones such as melatonin increases ischemic heart disease risk. The nuclear melatonin receptors RORs are pivotally involved in circadian rhythm regulation and melatonin effects mediation. However, the functional roles of RORs in the heart have never been investigated and were therefore the subject of this study on myocardial ischemia/reperfusion (MI/R) injury pathogenesis. RORα and RORγ subtypes were detected in the adult mouse heart, and RORα but not RORγ was downregulated after MI/R. To determine the pathological consequence of MI/R-induced reduction of RORα, we subjected RORα-deficient staggerer mice and wild-type (WT) littermates to MI/R injury, resulting in significantly increased myocardial infarct size, myocardial apoptosis and exacerbated contractile dysfunction in the former. Mechanistically, RORα deficiency promoted MI/R-induced endoplasmic reticulum stress, mitochondrial impairments, and autophagy dysfunction. Moreover, RORα deficiency augmented MI/R-induced oxidative/nitrative stress. Given the emerging evidence of RORα as an essential melatonin effects mediator, we further investigated the RORα roles in melatonin-exerted cardioprotection, in particular against MI/R injury, which was significantly attenuated in RORα-deficient mice, but negligibly affected by cardiac-specific silencing of RORγ. Finally, to determine cell type-specific effects of RORα, we generated mice with cardiomyocyte-specific RORα overexpression and they were less vulnerable to MI/R injury. In summary, our study provides the first direct evidence that the nuclear melatonin receptor RORα is a novel endogenous protective receptor against MI/R injury and an important mediator of melatonin-exerted cardioprotection; melatonin-RORα axis signaling thus appears important in protection against ischemic heart injury.

  7. Effects of Nitrate Intake on Myocardial Ischemia-Reperfusion Injury in Diabetic Rats

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    Jeddi, Sajad; Khalifi, Saeedeh; Ghanbari, Mahboubeh; Bageripour, Fatemeh; Ghasemi, Asghar

    2016-01-01

    Background Coronary artery disease is 2-3 times more common in diabetic individuals. Dietary nitrate/nitrite has beneficial effects in both diabetes and cardiovascular disease. It also has protective effects against myocardial ischemia-reperfusion (IR) injury in healthy animals. However, the effects of nitrate on myocardial IR injury in diabetic rats have not yet been investigated. Objective We examined the effects of dietary nitrate on myocardial IR injury in streptozotocin-nicotinamide-induced diabetic rats. Method Rats were divided into four groups (n=7 in each group): control, control+nitrate, diabetes, and diabetes+nitrate. Type 2 diabetes was induced by injection of streptozotocin and nicotinamide. Nitrate (sodium nitrate) was added to drinking water (100 mg/L) for 2 months. The hearts were perfused in a Langendorff apparatus at 2 months and assessed before (baseline) and after myocardial IR for the following parameters: left ventricular developed pressure (LVDP), minimum and maximum rates of pressure change in the left ventricle (±dP/dt), endothelial nitric oxide (NO) synthase (eNOS) and inducible NO synthase (iNOS) mRNA expression, and levels of malondialdehyde (MDA) and NO metabolites (NOx). Results Recovery of LVDP and ±dP/dt was lower in diabetic rats versus controls, but almost normalized after nitrate intake. Diabetic rats had lower eNOS and higher iNOS expression both at baseline and after IR, and dietary nitrate restored these parameters to normal values after IR. Compared with controls, heart NOx level was lower in diabetic rats at baseline but was higher after IR. Diabetic rats had higher MDA levels both at baseline and after IR, which along with heart NOx levels decreased following nitrate intake. Conclusion Dietary nitrate in diabetic rats provides cardioprotection against IR injury by regulating eNOS and iNOS expression and inhibiting lipid peroxidation in the heart. PMID:27849257

  8. Impairment of endothelial-myocardial interaction increases the susceptibility of cardiomyocytes to ischemia/reperfusion injury.

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    Thorsten M Leucker

    Full Text Available Endothelial-myocardial interactions may be critically important for ischemia/reperfusion injury. Tetrahydrobiopterin (BH4 is a required cofactor for nitric oxide (NO production by endothelial NO synthase (eNOS. Hyperglycemia (HG leads to significant increases in oxidative stress, oxidizing BH4 to enzymatically incompetent dihydrobiopterin. How alterations in endothelial BH4 content impact myocardial ischemia/reperfusion injury remains elusive. The aim of this study was to examine the effect of endothelial-myocardial interaction on ischemia/reperfusion injury, with an emphasis on the role of endothelial BH4 content. Langendorff-perfused mouse hearts were treated by triton X-100 to produce endothelial dysfunction and subsequently subjected to 30 min of ischemia followed by 2 h of reperfusion. The recovery of left ventricular systolic and diastolic function during reperfusion was impaired in triton X-100 treated hearts compared with vehicle-treated hearts. Cardiomyocytes (CMs were co-cultured with endothelial cells (ECs and subsequently subjected to 2 h of hypoxia followed by 2 h of reoxygenation. Addition of ECs to CMs at a ratio of 1∶3 significantly increased NO production and decreased lactate dehydrogenase activity compared with CMs alone. This EC-derived protection was abolished by HG. The addition of 100 µM sepiapterin (a BH4 precursor or overexpression of GTP cyclohydrolase 1 (the rate-limiting enzyme for BH4 biosynthesis in ECs by gene trasfer enhanced endothelial BH4 levels, the ratio of eNOS dimer/monomer, eNOS phosphorylation, and NO production and decreased lactate dehydrogenase activity in the presence of HG. These results demonstrate that increased BH4 content in ECs by either pharmacological or genetic approaches reduces myocardial damage during hypoxia/reoxygenation in the presence of HG. Maintaining sufficient endothelial BH4 is crucial for cardioprotection against hypoxia/reoxygenation injury.

  9. Activation of SHH signaling pathway promotes vasculogenesis in post-myocardial ischemic-reperfusion injury

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    Guo, Wei; YI, XIN; Ren, Faxin; Liu, Liwen; WU, SUNING; Yang, Jun

    2015-01-01

    This study aimed to investigate the potential roles of sonic Hedgehog (SHH) expression in vasculogenesis in post-myocardial ischemic-reperfusion injury (MIRI) and its underlying mechanism. Cardiac microvascular endothelial cells (CMECs) isolated from the SD rat hearts tissues were used to construct the MIRI model. mRNA level of SHH in control cells and MIRI cells was detected using RT-PCR analysis. Furthermore, effects of SHH expression on CMECs viability and apoptosis were analyzed using MTT...

  10. Effects of Nitrate Intake on Myocardial Ischemia-Reperfusion Injury in Diabetic Rats

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    Sajad Jeddi

    Full Text Available Abstract Background: Coronary artery disease is 2-3 times more common in diabetic individuals. Dietary nitrate/nitrite has beneficial effects in both diabetes and cardiovascular disease. It also has protective effects against myocardial ischemia-reperfusion (IR injury in healthy animals. However, the effects of nitrate on myocardial IR injury in diabetic rats have not yet been investigated. Objective: We examined the effects of dietary nitrate on myocardial IR injury in streptozotocin-nicotinamide-induced diabetic rats. Method: Rats were divided into four groups (n=7 in each group: control, control+nitrate, diabetes, and diabetes+nitrate. Type 2 diabetes was induced by injection of streptozotocin and nicotinamide. Nitrate (sodium nitrate was added to drinking water (100 mg/L for 2 months. The hearts were perfused in a Langendorff apparatus at 2 months and assessed before (baseline and after myocardial IR for the following parameters: left ventricular developed pressure (LVDP, minimum and maximum rates of pressure change in the left ventricle (±dP/dt, endothelial nitric oxide (NO synthase (eNOS and inducible NO synthase (iNOS mRNA expression, and levels of malondialdehyde (MDA and NO metabolites (NOx. Results: Recovery of LVDP and ±dP/dt was lower in diabetic rats versus controls, but almost normalized after nitrate intake. Diabetic rats had lower eNOS and higher iNOS expression both at baseline and after IR, and dietary nitrate restored these parameters to normal values after IR. Compared with controls, heart NOx level was lower in diabetic rats at baseline but was higher after IR. Diabetic rats had higher MDA levels both at baseline and after IR, which along with heart NOx levels decreased following nitrate intake. Conclusion: Dietary nitrate in diabetic rats provides cardioprotection against IR injury by regulating eNOS and iNOS expression and inhibiting lipid peroxidation in the heart.

  11. Luteolin-7-diglucuronide attenuates isoproterenol-induced myocardial injury and fibrosis in mice

    Science.gov (United States)

    Ning, Bing-bing; Zhang, Yong; Wu, Dan-dan; Cui, Jin-gang; Liu, Li; Wang, Pei-wei; Wang, Wen-jian; Zhu, Wei-liang; Chen, Yu; Zhang, Teng

    2017-01-01

    Myocardial injury and ensuing fibrotic alterations impair normal heart architecture and cause cardiac dysfunction. Oxidative stress has been recognized as a key player in the pathogenesis of cardiac injury and progression of cardiac dysfunction, and promoting fibrosis. In the current study we investigated whether luteolin-7-diglucuronide (L7DG), a naturally occurring antioxidant found in edible plants, could attenuate isoproterenol (ISO)-induced myocardial injury and fibrosis in mice and the underlying mechanisms. Myocardial injury and fibrosis were induced in mice via injection of ISO (5 mg·kg−1·d−1, ip) for 5 or 10 d. Two treatment regimens (pretreatment and posttreatment) were employed to administer L7DG (5–40 mg·kg−1·d−1, ip) into the mice. After the mice were euthanized, morphological examinations of heart sections revealed that both L7DG pretreatment and posttreatment regimens significantly attenuated ISO-induced myocardial injury and fibrosis. But the pretreatment regimen caused better protection against ISO-induced myocardial fibrosis than the posttreatment regimen. Furthermore, L7DG pretreatment blocked ISO-stimulated expression of the genes (Cyba, Cybb, Ncf1, Ncf4 and Rac2) encoding the enzymatic subunits of NADPH oxidase, which was the primary source of oxidant production in mammalian cells. Moreover, L7DG pretreatment significantly suppressed ISO-stimulated expression of collagen genes Col1a1, Col1a2, Col3a1, and Col12a1 and non-collagen extracellular matrix genes fibrillin-1, elastin, collagen triple helix repeat containing 1 and connective tissue growth factor. In addition, L7DG pretreatment almost reversed ISO-altered expression of microRNAs that were crosstalking with TGFβ-mediated fibrosis, including miR-29c-3p, miR-29c-5p, miR-30c-3p, miR-30c-5p and miR-21. The current study demonstrated for the first time that L7DG is pharmacologically effective in protecting the heart against developing ISO-induced injury and fibrosis, justifying

  12. Effects of liraglutide and ischemic postconditioning on myocardial salvage after I/R injury in pigs

    DEFF Research Database (Denmark)

    Ekström, Kathrine; Dalsgaard, Morten; Iversen, Kasper

    2017-01-01

    OBJECTIVES: Acute STEMI is routinely treated by acute PCI. This treatment may itself damage the tissue (reperfusion injury). Conditioning with GLP-1 analogs has been shown to reduce reperfusion injury. Likewise, ischemic postconditioning provides cardioprotection following STEMI. We tested...... assigned to four groups. Myocardial infarction (MI) was induced by occluding the LAD for 45 min. Group 1 (n = 14) was treated with i.v. liraglutide after 15 min of ischemia. Group 2 (n = 17) received liraglutide treatment concomitant with ischemic postconditioning, after 45 min of ischemia. Group 3 (n = 15...

  13. IMPACT OF MECHANICAL MYOCARDIAL INJURY PRODUCTS, LPS AND THEIR COMBINATION ON HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS

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    V. G. Matveeva

    2014-01-01

    Full Text Available Complicated systemic inflammatory response (SIR often determines the outcome in patients after cardiac surgery. Systemic endothelial activation plays the most important role in SIR pathogenesis. We have studied the impact of mechanical myocardial injury products, LPS and their combination on human umbilical vein endothelial cells (HUVEC. We have found that HUVEC increase the production of proinflammatory cytokines in response tocardiomyocyte cytosolic fraction responsible for mechanical injury modeling. 2% cytosolic fraction containing 0.204 ng/mL of Hsp70 was a greater stimulus for endothelial cells to produce IL-6 and IL8 than moderateendotoxin concentrations.

  14. Electrophysiological studies of upregulated P2X7 receptors in rat superior cervical ganglia after myocardial ischemic injury.

    Science.gov (United States)

    Kong, Fanjun; Liu, Shuangmei; Xu, Changshui; Liu, Jun; Li, Guodong; Li, Guilin; Gao, Yun; Lin, Hong; Tu, Guihua; Peng, Haiying; Qiu, Shuyi; Fan, Bo; Zhu, Qicheng; Yu, Shicheng; Zheng, Chaoran; Liang, Shangdong

    2013-09-01

    Myocardial ischemic injury activates cardiac sympathetic afferent fibers and elicits a sympathoexcitatory reflex by exciting sympathetic efferent action, with resultant augmentation of myocardial oxygen consumption, leading to a vicious cycle of exaggerating myocardial ischemia. P2X7 receptor participates in the neuronal functions and the neurological disorders. This study examined the role of P2X7 receptor of superior cervical ganglia (SCG) in sympathoexcitatory reflex. Our results showed that the expression of P2X7 receptor at both mRNA and protein in SCG was increased after myocardial ischemic injury. P2X7 receptor agonists at the same concentration activated much larger amplitudes of the currents in the SCG neurons of myocardial ischemic rats than those in control rats. P2X7 receptor antagonist (brilliant blue G, BBG) significantly inhibited P2X7 receptor agonist-activated currents in the SCG neurons. Excessive phosphorylation of MAPK ERK1/2 upon the activation of P2X7 receptor might be a mechanism mediating the signal transduction after myocardial ischemic injury. Therefore, the sensitized P2X7 receptor in SCG was involved in the nociceptive transmission of sympathoexcitatory reflex induced by myocardial ischemic injury.

  15. Antiapoptotic Effect of Recombinant HMGB1 A-box Protein via Regulation of microRNA-21 in Myocardial Ischemia-Reperfusion Injury Model in Rats.

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    Han, Qiang; Zhang, Hua-Yong; Zhong, Bei-Long; Zhang, Bing; Chen, Hua

    2016-04-01

    The ~80 amino acid A box DNA-binding domain of high mobility group box 1 (HMGB1) protein antagonizes proinflammatory responses during myocardial ischemia reperfusion (I/R) injury. The exact role of microRNA-21 (miR-21) is unknown, but its altered levels are evident in I/R injury. This study examined the roles of HMGB1 A-box and miR-21 in rat myocardial I/R injury model. Sixty Sprague-Dawley rats were randomly divided into six equal groups: (1) Sham; (2) I/R; (3) Ischemic postconditioning (IPost); (4) AntagomiR-21 post-treatment; (5) Recombinant HMGB1 A-box pretreatment; and (6) Recombinant HMGB1 A-box + antagomiR-21 post-treatment. Hemodynamic indexes, arrhythmia scores, ischemic area and infarct size, myocardial injury, and related parameters were studied. Expression of miR-21 was detected by real-time quantitative polymerase chain reaction (qRT-PCR) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was used to quantify apoptosis. Left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximal rate of pressure rise (+dp/dtmax), and decline (-dp/dtmax) showed clear reduction upon treatment with recombinant HMGB1 A-box. Arrhythmia was relieved and infarct area decreased in the group pretreated with recombinant HMGB1 A-box, compared with other groups. Circulating lactate dehydrogenase (LDH) and malondialdehyde (MDA) levels increased in response to irreversible cellular injury, while creatine kinase MB isoenzymes (CK-MB) and superoxide dismutase (SOD) activities were reduced in the I/R group, which was reversed following recombinant HMGB1 A-box treatment. Interestingly, pretreatment with recombinant HMGB1 A-box showed the most dramatic reductions in miR-21 levels, compared with other groups. Significantly reduced apoptotic index (AI) was seen in recombinant HMGB1 A-box pretreatment group and recombinant HMGB1 A-box + antagomiR-21 post-treatment group, with the former showing a more

  16. Suv39h1 Protects from Myocardial Ischemia-Reperfusion Injury in Diabetic Rats

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    Bo Yang

    2014-04-01

    Full Text Available Background: Patients with diabetes are at increased risk of ischemic events. Suv39h1 is a histone methyltransferase that catalyzes the methylation of histone 3 lysine 9, which is associated with the suppression of inflammatory genes in diabetes. However, the role of Suv39h1 in myocardial ischemia/reperfusion (I/R injury under diabetic condition has not been evaluated. Methods: To generate diabetic model, male SD rats were fed with 60% fat diet followed by intraperitoneal injection with 40mg/kg streptozotocin. Adenovirus encoding Suv39h1 gene was used for Suv39h1 overexpression. Each rat received injections of adenovirus at five myocardial sites. Three days after gene transfection, each rat was subjected to left main coronary artery occlusion and reperfusion. After 30 min ischemia and reperfusion for 4 h, the rats were euthanized for real-time PCR, Western blot, immunohistochemical staining, and morphometric analysis. Results: Delivery of Ad-Suv39h1 into the hearts of diabetic rats could markedly increase Suv39h1 expression. Up-regulation of Suv39h1 significantly reduced infarct size and tissue damage after I/R injury, which was associated with protection from apoptosis of cardiac myocytes and reduction of inflammatory response. In addition, compared with injury group, Ad-Suv39h1 led to a decreased activity of mitogen-activated protein kinase family and its down-steam transcriptional factor NF-κB. Conclusion: Overexpression of Suv39h1 results in the de-activation of proinflammatory pathways and reduced apoptosis and myocardial injury. Therefore, Suv39h1 might represent a novel therapeutic strategy to reduce I/R injury under diabetic condition.

  17. Protective effect and mechanism of lithium chloride pretreatment on myocardial ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Fang-Jiang Li; Tao Hsu; Hui-Xian Li; Jin-Zheng Shi; Mei-Ling Du; Xiao-Yuan Wang; Wen-Ting Zhang

    2014-01-01

    Objective:To investigate the protective effect and mechanism of lithium chloride pretreatment on myocardial ischemia-reperfusion injury(I-RI) in rats.Methods:A total of60SD rats were randomly divided into control group, model group, lithium chloride intervention group and L-arginine methyl ester+ lithium chloride intervention group with15 in each.TheI-RI model was established in model group, the lithium chloride intervention group andL-arginine methyl ester+ lithium chloride intervention group by method of seaming along left anterior descending coronary artery myocardial, control group was only opened the chest without seaming,ST-elevation within2 min was regarded as modeling success.Model group did not adopted any intervention, lithium chloride intervention group was treated with lithium chloride injection 15 mg/kg by jugular venipuncture preoperatively,L-arginine methyl ester+ lithium chloride intervention group was treated with intraperitoneal injection of30 mg•kg-1•d-1L-arginine methyl ester7 d before the test, and intravenous catheter of15 mg/kg lithium chloride preoperatively. The hydroxybutyric acid dehydrogenase(HBDH), creatine kinase isoenzyme(CK-MB), superoxide dismutase(SOD), malondialdehyde(MDA) level and nitric oxide synthase(NOS) activites were tested.Each large area of myocardial ischemia tissue was extracted for determination of the MDA content,SOD activity in tissue and serum, and morphological changes of myocardial tissue.Results:SOD activity was highest in lithium chloride intervention group, followed by L-arginine methyl ester+ lithium chloride intervention group, control group and model group (P0.05);HBDH andCK-MB of plasma were highest in model group, followed byL-arginine methyl ester+ lithium chloride intervention group, lithium chloride intervention group and control group(P<0.05).A significantly lighter myocardial damage was observed microscopically in lithium chloride intervention group than that inL-arginine methyl ester+ lithium

  18. S-nitrosation of calpains is associated with cardioprotection in myocardial I/R injury.

    Science.gov (United States)

    Totzeck, Matthias; Korste, Sebastian; Miinalainen, Ilkka; Hendgen-Cotta, Ulrike B; Rassaf, Tienush

    2017-07-01

    Myocardial infarction remains the single leading cause of death worldwide. Upon reperfusion of occluded arteries, deleterious cellular mediators particularly located at the mitochondria level can be activated, thus limiting the outcome in patients. This may lead to the so-called ischemia/reperfusion (I/R) injury. Calpains are cysteine proteases and mediators of caspase-independent cell death. Recently, they have emerged as central transmitters of cellular injury in several cardiac pathologies e.g. hypertrophy and acute I/R injury. Here we investigated the role of cardiac calpains in acute I/R in relation to mitochondrial integrity and whether calpains can be effectively inhibited by posttranslational modification by S-nitrosation. Taking advantage of the a cardiomyocyte cell line (HL1), we determined S-nitrosation by the Biotin-switch approach, cell viability and intracellular calcium concentration after simulated ischemia and reoxygenation - all in dependence of supplementation with nitrite, which is known as an 'hypoxic nitric oxide (NO) donor'. Likewise, using an in vivo I/R model, calpain S-nitrosation, calpain activity and myocardial I/R injury were characterized in vivo. Nitrite administration resulted in an increased S-nitrosation of calpains, and this was associated with an improved cell-survival. No impact was detected on calcium levels. In line with these in vitro experiments, nitrite initiated calpain S-nitrosation in vivo and caused an infarct sparing effect in an in vivo myocardial I/R model. Using electron microscopy in combination with immuno-gold labeling we determined that calpain 10 increased, while calpain 2 decreased in the course of I/R. Nitrite, in turn, prevented an I/R induced increase of calpains 10 at mitochondria and reduced levels of calpain 1. Lethal myocardial injury remains a key aspect of myocardial I/R. We show that calpains, as key players in caspase-independent apoptosis, increasingly locate at mitochondria following I

  19. Amelioration of myocardial ischemic reperfusion injury with Calendula officinalis.

    Science.gov (United States)

    Ray, Diptarka; Mukherjee, Subhendu; Falchi, Mario; Bertelli, Aldo; Das, Dipak K

    2010-12-01

    Calendula officinalis of family Asteraceae, also known as marigold, has been widely used from time immemorial in Indian and Arabic cultures as an anti-inflammatory agent to treat minor skin wound and infections, burns, bee stings, sunburn and cancer. At a relatively high dose, calendula can lower blood pressure and cholesterol. Since inflammatory responses are behind many cardiac diseases, we sought to evaluate if calendula could be cardioprotective against ischemic heart disease Two groups of hearts were used: the treated rat hearts were perfused with calendula solution at 50 mM in KHB buffer (in mM: sodium chloride 118, potassium chloride 4.7, calcium chloride 1.7, sodium bicarbonate 25, potassium biphosphate 0.36, magnesium sulfate 1.2, and glucose 10) for 15 min prior to subjecting the heart to ischemia, while the control group was perfused with the buffer only. Calendula achieved cardioprotection by stimulating left ventricular developed pressure and aortic flow as well as by reducing myocardial infarct size and cardiomyocyte apoptosis. Cardioprotection appears to be achieved by changing ischemia reperfusion-mediated death signal into a survival signal by modulating antioxidant and anti-inflammatory pathways as evidenced by the activation of Akt and Bcl2 and depression of TNFα. The results further strengthen the concept of using natural products in degeneration diseases like ischemic heart disease.

  20. Contribution of calpains to myocardial ischaemia/reperfusion injury.

    Science.gov (United States)

    Inserte, Javier; Hernando, Victor; Garcia-Dorado, David

    2012-10-01

    Loss of calcium (Ca(2+)) homeostasis contributes through different mechanisms to cell death occurring during the first minutes of reperfusion. One of them is an unregulated activation of a variety of Ca(2+)-dependent enzymes, including the non-lysosomal cysteine proteases known as calpains. This review analyses the involvement of the calpain family in reperfusion-induced cardiomyocyte death. Calpains remain inactive before reperfusion due to the acidic pHi and increased ionic strength in the ischaemic myocardium. However, inappropriate calpain activation occurs during myocardial reperfusion, and subsequent proteolysis of a wide variety of proteins contributes to the development of contractile dysfunction and necrotic cell death by different mechanisms, including increased membrane fragility, further impairment of Na(+) and Ca(2+) handling, and mitochondrial dysfunction. Recent studies demonstrating that calpain inhibition contributes to the cardioprotective effects of preconditioning and postconditioning, and the beneficial effects obtained with new and more selective calpain inhibitors added at the onset of reperfusion, point to the potential cardioprotective value of therapeutic strategies designed to prevent calpain activation.

  1. The triterpenoids of Ganoderma tsugae prevent stress-induced myocardial injury in mice.

    Science.gov (United States)

    Kuok, Qian-Yu; Yeh, Chen-Yu; Su, Bor-Chyuan; Hsu, Pei-Ling; Ni, Hao; Liu, Ming-Yie; Mo, Fan-E

    2013-10-01

    Ganoderma mushrooms (Lingzhi in Chinese) have well-documented health benefits. Ganoderma tsugae (G. tsugae), one of the ganoderma species, has been commercially cultivated as a dietary supplement. Because G. tsugae has high antioxidant activity and because oxidative stress is often associated with cardiac injury, we hypothesized that G. tsugae protects against cardiac injury by alleviating oxidative stress. We tested the hypothesis using a work-overload-induced myocardial injury model created by challenging mice with isoproterenol (ISO). Remarkably, oral G. tsugae protected the mice from ISO-induced myocardial injury. Moreover, the triterpenoid fraction of G. tsugae, composed of a mixture of nine structurally related ganoderic acids (GAs), provided cardioprotection by inhibiting the ISO-induced expression of Fas/Fas ligand, oxidative stress, and apoptosis. The antioxidant activity of GAs was tested in cultured cardio-myoblast H9c2 cells against the insult of H₂O₂. GAs dissipated the cellular reactive oxygen species imposed by H₂O₂ and prevented cell death. Our findings uncovered the cardioprotective activity of G. tsugae and identified GAs as the bioactive components against cardiac insults.

  2. Cardioprotection by a novel recombinant serine protease inhibitor in myocardial ischemia and reperfusion injury.

    Science.gov (United States)

    Murohara, T; Guo, J P; Lefer, A M

    1995-09-01

    Polymorphonuclear neutrophils (PMN) play an important role in myocardial ischemia/reperfusion (MI/R) injury; however, the role of neutrophilic proteases is less understood. The effects of a novel serine protease inhibitor (serpin), LEX032, were investigated in a murine model of MI (20 min) and R (24 hr) injury in vivo. LEX032 is a recombinant human alpha 1-antichymotrypsin in which six amino acid residues were replaced around the active center with those of alpha-1 protease inhibitor. LEX032 has the ability to inhibit both neutrophil elastase and cathepsin G, two major neutral serine proteases in neutrophils, as well as superoxide generation. LEX032 (25 or 50 mg/kg) administered i.v. 1 min before reperfusion significantly attenuated myocardial necrotic injury evaluated by cardiac creatine kinase loss compared to MI/R rats receiving only vehicle (P LEX032 as compared with rats receiving vehicle (P LEX032 also moderately attenuated leukotriene B4-stimulated PMN adherence to rat superior mesenteric artery endothelium and markedly diminished superoxide radical release from LTB4-stimulated PMN in vitro. In a glycogen-induced rat peritonitis model, LEX032 (50 mg/kg) significantly attenuated PMN transmigration into the peritoneal cavity in vivo. In conclusion, the recombinant serine protease inhibitor, LEX032, appears to be an effective agent for attenuating MI/R injury by inhibiting neutrophil-accumulation into the ischemic-reperfused myocardium and by inactivating cytotoxic metabolites (proteases and superoxide radical) released from neutrophils.

  3. The diagnostic value of both troponin T and creatinine kinase isoenzyme (CK-MB) in detecting combined renal and myocardial injuries in asphyxiated infants.

    Science.gov (United States)

    Sadoh, Wilson E; Eregie, Charles O; Nwaneri, Damian U; Sadoh, Ayebo E

    2014-01-01

    Troponin T (cTnT) and Creatinine Kinase Isoenzyme (CK-MB) are both markers of myocardial injuries. However, CK-MB is also elevated in acute kidney injury. The diagnostic value of both cTnT and cardiac CK-MB in combined myocardial and acute kidney injuries (AKI) in asphyxiated neonates was evaluated. 40 asphyxiated infants and 40 non-asphyxiated controls were consecutively recruited. Serum levels of cTnT, CK-MB and creatinine were measured. Myocardial injury and AKI were defined as cTnT >95th percentile of the control and serum creatinine >1.0 mg/dl respectively. Of the 40 subjects, 9 (22.50%), 8 (20.00%) and 4 (10.00%) had myocardial injury, AKI and combined AKI and myocardial injuries respectively. The mean cTnT and CK-MB values were highest in infants with combined AKI and myocardial injuries. The Mean cTnT in infants with AKI, myocardial injury and combined AKI and myocardial injuries were 0.010±0.0007 ng/ml, 0.067±0.040 ng/ml and 0.084±0.067 ng/ml respectively, p = 0.006. The mean CK-MB in infants with AKI, myocardial injury and combined AKI and myocardial injuries were 2.78±0.22 ng/ml, 1.28±0.11 ng/ml and 4.58±0.52 ng/ml respectively, p = MB indicates either myocardial injury, AKI or both. Therefore renal injury should be excluded in asphyxiated infants with elevated CK-MB.

  4. Matrix metaHoproteinase-8 inhibitors mitigate sepsis-induced myocardial injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zhou Xiaorui; Lu Jiakai; Chen Dong; Wang Wei; Cai Qing; Li Tongxun; Zhang Jinglan

    2014-01-01

    Background Sepsis-induced myocardial injury (SIMI) is caused by a variety of mechanisms.The aim of the study is to investigate the effects of metalloproteinase-8 (MMP-8) on SIMI and its mechanisms in rats.Methods Forty male Sprague Dawley rats were randomly divided into four groups:MMP-8 inhibitor (M8I),dexamethasone (DEX),sepsis,and sham groups.The sepsis model was established by cecal ligation and puncture (CLP).Rats in the M8I group immediately received an intraperitoneal injection of M8I (0.1 mg/kg) after CLP.Rats in the DEX group immediately received an intraperitoneal (IP) injection of DEX (2 mg/kg).Rats in the sepsis and sham groups received intraperitoneal injections of normal saline.Rats were sacrificed 12 hours after CLP.Paraffin sections were stained with hematoxylin and eosin to observe the myocardium.The myocardial ultrastructure was observed with transmission electron microscopy.MMP-8,tumor necrosis factor-α (TNF-α),and interleukin-1β (IL-1β) were detected by immunohistochemistry.The expression of MMP-8 was measured by Western blotting.TNF-α and IL-1β levels in serum and myocardial tissue were determined by enzyme-linked immunosorbent assay.Results Compared with the sham group,the myocardium in the sepsis group was seriously injured.MMP-8,TNF-α and IL-1β expression was higher in the sepsis group than in the sham group.Treatment with M8I or DEX,however,attenuated sepsis induced histopathological changes in the heart,and was associated with significant reductions in serum and myocardial levels of TNF-α and IL-1β (P <0.05).M8I significantly inhibited MMP-8 expression in myocardial tissue (P <0.05).In addition,treatment with DEX was not associated with a change in myocardial levels of MMP-8 (P >0.05).Conclusion MMP-8 inhibitor attenuated myocardial injury in septic rats,which might be related to reduced expression of TNF-α and IL-1β.

  5. N-Acetylcysteine Attenuates Diabetic Myocardial Ischemia Reperfusion Injury through Inhibiting Excessive Autophagy

    Science.gov (United States)

    Wang, Sheng; Yan, Fuxia; Wang, Tingting; He, Yi

    2017-01-01

    Background. Excessive autophagy is a major mechanism of myocardial ischemia reperfusion injury (I/RI) in diabetes with enhanced oxidative stress. Antioxidant N-acetylcysteine (NAC) reduces myocardial I/RI. It is unknown if inhibition of autophagy may represent a mechanism whereby NAC confers cardioprotection in diabetes. Methods and Results. Diabetes was induced in Sprague-Dawley rats with streptozotocin and they were treated without or with NAC (1.5 g/kg/day) for four weeks before being subjected to 30-minute coronary occlusion and 2-hour reperfusion. The results showed that cardiac levels of 15-F2t-Isoprostane were increased and that autophagy was evidenced as increases in ratio of LC3 II/I and protein P62 and AMPK and mTOR expressions were significantly increased in diabetic compared to nondiabetic rats, concomitant with increased postischemic myocardial infarct size and CK-MB release but decreased Akt and eNOS activation. Diabetes was also associated with increased postischemic apoptotic cell death manifested as increases in TUNEL positive cells, cleaved-caspase-3, and ratio of Bax/Bcl-2 protein expression. NAC significantly attenuated I/RI-induced increases in oxidative stress and cardiac apoptosis, prevented postischemic autophagy formation in diabetes, and reduced postischemic myocardial infarction (all p < 0.05). Conclusions. NAC confers cardioprotection against diabetic heart I/RI primarily through inhibiting excessive autophagy which might be a major mechanism why diabetic hearts are less tolerant to I/RI. PMID:28265179

  6. Thymoquinone Protects against Myocardial Ischemic Injury by Mitigating Oxidative Stress and Inflammation

    Directory of Open Access Journals (Sweden)

    Shreesh Ojha

    2015-01-01

    Full Text Available The present study was aimed at investigating the cardioprotective activity of thymoquinone (TMQ, an active principle of the herb, Nigella sativa, which is used for the management of various diseases. The present study examined the cardioprotective effect of TMQ in isoproterenol- (ISP- induced myocardial infarction in rats. Myocardial infarction was induced by two subcutaneous injections of ISP (85 mg/kg at an interval of 24 hr. TMQ (20 mg/kg was administered orally for 21 days. ISP-treated rats showed depletion of antioxidants and marker enzymes from myocardium along with lipid peroxidation and enhanced levels of proinflammatory cytokines. ISP also induced histopathological alterations in myocardium. Treatment with TMQ prevented the depletion of endogenous antioxidants and myocyte injury marker enzymes and inhibited lipid peroxidation as well as reducing the levels of proinflammatory cytokines. TMQ pretreatment also reduced myonecrosis, edema, and infiltration of inflammatory cells and showed preservation of cardiomyocytes histoarchitecture. The present study results demonstrate that TMQ exerts cardioprotective effect by mitigating oxidative stress, augmenting endogenous antioxidants, and maintaining structural integrity. The results of the present study indicate that TMQ may serve as an excellent agent alone or as adjuvant to prevent the onset and progression of myocardial injury.

  7. Hypercholesterolemia aggravates myocardial ischemia reperfusion injury via activating endoplasmic reticulum stress-mediated apoptosis.

    Science.gov (United States)

    Wu, Nan; Zhang, Xiaowen; Jia, Pengyu; Jia, Dalin

    2015-12-01

    The effect of hypercholesterolemia on myocardial ischemia reperfusion injury (MIRI) is in controversy and the underlying mechanism is still not well understood. In the present study, we firstly detected the effects of hypercholesterolemia on MIRI and the role of endoplasmic reticulum (ER) stress-mediated apoptosis pathway in this process. The infarct size was determined by TTC staining, and apoptosis was measured by the TUNEL method. The marker proteins of ER stress response and ER stress-mediated apoptosis pathway were detected by Western blot. The results showed that high cholesterol diet-induced hypercholesterolemia significantly increased the myocardial infarct size, the release of myocardium enzyme and the ratio of apoptosis, but did not affect the recovery of cardiac function. Moreover, hypercholesterolemia also remarkably up-regulated the expressions of ER stress markers (glucose-regulated protein 78 and calreticulin) and critical molecules in ER stress-mediated apoptosis pathway (CHOP, caspase 12, phospho-JNK). In conclusion, our study demonstrated that hypercholesterolemia enhanced myocardial vulnerability/sensitivity to ischemia reperfusion injury involved in aggravation the ER stress and activation of ER stress-mediated apoptosis pathway and it gave us a new insight into the underlying mechanisms associated with hypercholesterolemia-induced exaggerated MIRI and also provided a novel target for preventing MIRI in the presence of hypercholesterolemia. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Sex-dependent effects of sleep deprivation on myocardial sensitivity to ischemic injury.

    Science.gov (United States)

    Zoladz, Phillip R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah L; Fry, Megan E; Johnson, Brandon L; Rorabaugh, Boyd R

    2016-01-01

    Sleep deprivation is associated with increased risk of myocardial infarction. However, it is unknown whether the effects of sleep deprivation are limited to increasing the likelihood of experiencing a myocardial infarction or if sleep deprivation also increases the extent of myocardial injury. In this study, rats were deprived of paradoxical sleep for 96 h using the platform-over-water method. Control rats were subjected to the same condition except the control platform was large enough for the rats to sleep. Hearts from sleep deprived and control rats were subjected to 20 min ischemia on a Langendorff isolated heart system. Infarct size and post ischemic recovery of contractile function were unaffected by sleep deprivation in male hearts. In contrast, hearts from sleep-deprived females exhibited significantly larger infarcts than hearts from control females. Post ischemic recovery of rate pressure product and + dP/dT were significantly attenuated by sleep deprivation in female hearts, and post ischemic recovery of end diastolic pressure was significantly elevated in hearts from sleep deprived females compared to control females, indicating that post ischemic recovery of both systolic and diastolic function were worsened by sleep deprivation. These data provide evidence that sleep deprivation increases the extent of ischemia-induced injury in a sex-dependent manner.

  9. Endurance exercise accelerates myocardial tissue oxygenation recovery and reduces ischemia reperfusion injury in mice.

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    Yuanjing Li

    Full Text Available Exercise training offers cardioprotection against ischemia and reperfusion (I/R injury. However, few essential signals have been identified to underscore the protection from injury. In the present study, we hypothesized that exercise-induced acceleration of myocardial tissue oxygenation recovery contributes to this protection. C57BL/6 mice (4 weeks old were trained on treadmills for 45 min/day at a treading rate of 15 m/min for 8 weeks. At the end of 8-week exercise training, mice underwent 30-min left anterior descending coronary artery occlusion followed by 60-min or 24-h reperfusion. Electron paramagnetic resonance oximetry was performed to measure myocardial tissue oxygenation. Western immunoblotting analyses, gene transfection, and myography were examined. The oximetry study demonstrated that exercise markedly shortened myocardial tissue oxygenation recovery time following reperfusion. Exercise training up-regulated Kir6.1 protein expression (a subunit of ATP-sensitive K(+channel on vascular smooth muscle cells, VSMC sarc-K(ATP and protected the heart from I/R injury. In vivo gene transfer of dominant negative Kir6.1AAA prolonged the recovery time and enlarged infarct size. In addition, transfection of Kir6.1AAA increased the stiffness and reduced the relaxation capacity in the vasculature. Together, our study demonstrated that exercise training up-regulated Kir6.1, improved tissue oxygenation recovery, and protected the heart against I/R injury. This exercise-induced cardioprotective mechanism may provide a potential therapeutic intervention targeting VSMC sarc-K(ATP channels and reperfusion recovery.

  10. Apyrase treatment of myocardial infarction according to a clinically applicable protocol fails to reduce myocardial injury in a porcine model

    Directory of Open Access Journals (Sweden)

    Otto Andreas

    2010-01-01

    Full Text Available Abstract Background Ectonucleotidase dependent adenosine generation has been implicated in preconditioning related cardioprotection against ischemia-reperfusion injury, and treatment with a soluble ectonucleotidase has been shown to reduce myocardial infarct size (IS when applied prior to induction of ischemia. However, ectonucleotidase treatment according to a clinically applicable protocol, with administration only after induction of ischemia, has not previously been evaluated. We therefore investigated if treatment with the ectonucleotidase apyrase, according to a clinically applicable protocol, would reduce IS and microvascular obstruction (MO in a large animal model. Methods A percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 min, in 16 anesthetized pigs (40-50 kg. The pigs were randomized to 40 min of 1 ml/min intracoronary infusion of apyrase (10 U/ml, n = 8 or saline (0.9 mg/ml, n = 8, twenty minutes after balloon inflation. Area at risk (AAR was evaluated by ex vivo SPECT. IS and MO were evaluated by ex vivo MRI. Results No differences were observed between the apyrase group and saline group with respect to IS/AAR (75.7 ± 4.2% vs 69.4 ± 5.0%, p = NS or MO (10.7 ± 4.8% vs 11.4 ± 4.8%, p = NS, but apyrase prolonged the post-ischemic reactive hyperemia. Conclusion Apyrase treatment according to a clinically applicable protocol, with administration of apyrase after induction of ischemia, does not reduce myocardial infarct size or microvascular obstruction.

  11. Captopril Pretreatment Produces an Additive Cardioprotection to Isoflurane Preconditioning in Attenuating Myocardial Ischemia Reperfusion Injury in Rabbits and in Humans.

    Science.gov (United States)

    Tian, Yi; Li, Haobo; Liu, Peiyu; Xu, Jun-mei; Irwin, Michael G; Xia, Zhengyuan; Tian, Guogang

    2015-01-01

    Pretreatment with the angiotensin-converting inhibitor captopril or volatile anesthetic isoflurane has, respectively, been shown to attenuate myocardial ischemia reperfusion (MI/R) injury in rodents and in patients. It is unknown whether or not captopril pretreatment and isoflurane preconditioning (Iso) may additively or synergistically attenuate MI/R injury. Patients selected for heart valve replacement surgery were randomly assigned to five groups: untreated control (Control), captopril pretreatment for 3 days (Cap3d), or single dose captopril (Cap1hr, 1 hour) before surgery with or without Iso (Cap3d+Iso and Cap1hr+Iso). Rabbit MI/R model was induced by occluding coronary artery for 30 min followed by 2-hour reperfusion. Rabbits were randomized to receive sham operation (Sham), MI/R (I/R), captopril (Cap, 24 hours before MI/R), Iso, or the combination of captopril and Iso (Iso+Cap). In patients, Cap3d+Iso but not Cap1hr+Iso additively reduced postischemic myocardial injury and attenuated postischemic myocardial inflammation. In rabbits, Cap or Iso significantly reduced postischemic myocardial infarction. Iso+Cap additively reduced cellular injury that was associated with improved postischemic myocardial functional recovery and reduced myocardial apoptosis and attenuated oxidative stress. A joint use of 3-day captopril treatment and isoflurane preconditioning additively attenuated MI/R by reducing oxidative stress and inflammation.

  12. The Role of Oxidative Stress in Myocardial Ischemia and Reperfusion Injury and Remodeling: Revisited

    Directory of Open Access Journals (Sweden)

    Gino A. Kurian

    2016-01-01

    Full Text Available Oxidative and reductive stress are dual dynamic phases experienced by the cells undergoing adaptation towards endogenous or exogenous noxious stimulus. The former arises due to the imbalance between the reactive oxygen species production and antioxidant defenses, while the latter is due to the aberrant increase in the reducing equivalents. Mitochondrial malfunction is the common denominator arising from the aberrant functioning of the rheostat that maintains the homeostasis between oxidative and reductive stress. Recent experimental evidences suggest that the maladaptation during oxidative stress could play a pivotal role in the pathophysiology of major cardiovascular diseases such as myocardial infraction, atherosclerosis, and diabetic cardiovascular complications. In this review we have discussed the role of oxidative and reductive stress pathways in the pathogenesis of myocardial ischemia/reperfusion injury and diabetic cardiomyopathy (DCM. Furthermore, we have provided impetus for the development of subcellular organelle targeted antioxidant drug therapy for thwarting the deterioration of the failing myocardium in the aforementioned cardiovascular conditions.

  13. Coronary arterial BK channel dysfunction exacerbates ischemia/reperfusion-induced myocardial injury in diabetic mice.

    Science.gov (United States)

    Lu, Tong; Jiang, Bin; Wang, Xiao-Li; Lee, Hon-Chi

    2016-09-01

    The large conductance Ca(2+)-activated K(+) (BK) channels, abundantly expressed in coronary artery smooth muscle cells (SMCs), play a pivotal role in regulating coronary circulation. A large body of evidence indicates that coronary arterial BK channel function is diminished in both type 1 and type 2 diabetes. However, the consequence of coronary BK channel dysfunction in diabetes is not clear. We hypothesized that impaired coronary BK channel function exacerbates myocardial ischemia/reperfusion (I/R) injury in streptozotocin-induced diabetic mice. Combining patch-clamp techniques and cellular biological approaches, we found that diabetes facilitated the colocalization of angiotensin II (Ang II) type 1 receptors and BK channel α-subunits (BK-α), but not BK channel β1-subunits (BK-β1), in the caveolae of coronary SMCs. This caveolar compartmentation in vascular SMCs not only enhanced Ang II-mediated inhibition of BK-α but also produced a physical disassociation between BK-α and BK-β1, leading to increased infarct size in diabetic hearts. Most importantly, genetic ablation of caveolae integrity or pharmacological activation of coronary BK channels protected the cardiac function of diabetic mice from experimental I/R injury in both in vivo and ex vivo preparations. Our results demonstrate a vascular ionic mechanism underlying the poor outcome of myocardial injury in diabetes. Hence, activation of coronary BK channels may serve as a therapeutic target for cardiovascular complications of diabetes.

  14. Effect of pre- and posttreatment of losartan in feline model of myocardial ischemic-reperfusion injury.

    Science.gov (United States)

    Kumari, R; Manchanda, S C; Maulik, S K

    2004-01-01

    This study investigated the differential effect of losartan, an AT1 receptor blocker, when administered in pre- and postischemic phases, on the biochemical, hemodynamic and oxidative stress associated with regional ischemic-reperfusion injury in cat. Losartan (5 microg/kg/min) or normal saline was administered intravenously in open chest barbiturate anesthetized cats, 15 min before and 10 min after the occlusion of the left anterior descending (LAD) coronary artery. The LAD was occluded for 15 min followed by 60 min reperfusion. In the saline treated group, there was significant depression of hemodynamic functions, i.e., mean arterial pressure (MAP), heart rate (HR), left ventricular end diastolic pressure (LVEDP) and left ventricular (LV) peak (+/-) dP/dt, along with depletion of adenosine triphosphate (ATP) of the affected myocardium. Oxidative stress during reperfusion injury was evidenced by significant increase in plasma thiobarbituric acid reactive substances (TBARS) accompanied by significant reduction in myocardial superoxide dismutase (SOD) activities. In both treatment groups, losartan caused recovery of all the hemodynamic parameters and repletion of ATP along with no significant change in plasma TBARS and myocardial SOD activity. There was no effect on catalase activity. Results from the study suggest that the effects of pre- and posttreatment of losartan are comparable in functional recovery of the heart from ischemic-reperfusion injury. (c) 2004 Prous Science. All rights reserved.

  15. Mediated protective effect of electroacupuncture pretreatment by miR-214 on myocardial ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Pei-Yu LIU; Yi TIAN; Shi-Yuan XU

    2014-01-01

    Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion (I/R) injury and microRNAs (miRNAs) could act on various facets of cardiac function. However, the role of miRNAs in the cardioprotection by electroacupuncture pre-treatment on myocardial I/R injury remains unknown. The purpose of the study was to examine whether miR-214 was involved in cardio-protection by electroacupuncture. Methods Using rat myocardial I/R model, we examined the role of electroacupuncture pretreatment in myocardial I/R injury and analyzed the changes in the expression of miR-214. In addition, I/R was simulated in vitro by performing oxy-gen-glucose deprivation (OGD) on H9c2 cell cultures, and the effect of electroacupuncture pretreatment on I/R injury as well as expressional level of miR-214 were examined in vitro. Furthermore, the miR-214 mimic was transfected into OGD-treated H9c2 cells, we analyzed the cell apoptosis, lactate dehydrogenase (LDH) and creatine kinase (CK) activities, intracellular free Ca2+concentration ([Ca2+]i) as well as the relative protein levels of sodium/calcium exchanger 1(NCX1), BCL2-like 11 (BIM), calmodulin-dependent protein kinase IIδ(CaMKIIδ) and Cyclophilin D (CypD). Results The in vivo results revealed that compared with the I/R group, the electroacupuncture pretreatment group showed significant decreased myocardial infarct size, as well as the increased indices of the cardiac function, including heart rate, mean arterial pressure, left ventricular systolic pressure and maximal rate for left ventricular pressure rising and declining (±dp/dt max). In addition, electroacupuncture pretreatment could inhibit the elevation of LDH and CK activities induced by I/R injury. The quantitative PCR (qPCR) results demonstrated electroacupuncture pretreatment could provide cardioprotection against myocardial I/R injury in rats with miR-214 up-regulation. In the meanwhile, in vitro, electroacupuncture pretreatment protected H9

  16. Sodium hydrosulfide attenuates hyperhomocysteinemia rat myocardial injury through cardiac mitochondrial protection.

    Science.gov (United States)

    Wang, Yuwen; Shi, Sa; Dong, Shiyun; Wu, Jichao; Song, Mowei; Zhong, Xin; Liu, Yanhong

    2015-01-01

    Hydrogen sulfide (H2S) plays an important role during rat myocardial injury. However, little is known about the role of H2S in hyperhomocysteinemia (HHcy)-induced cardiac dysfunction as well as the underlying mechanisms. In this study, we investigated whether sodium hydrosulfide (NaHS, a H2S donor) influences methionine-induced HHcy rat myocardial injury in intact rat hearts and primary neonatal rat cardiomyocytes. HHcy rats were induced by methionine (2.0 g/kg) and the daily administration of 80 μmol/L NaHS in the HHcy + NaHS treatment group. At the end of 4, 8, and 12 weeks, the ultrastructural alterations and functions of the hearts were observed using transmission electron microscopy and echocardiography system. The percentage of apoptotic cardiomyocytes, the mitochondrial membrane potential, and the production of reactive oxygen species (ROS) were measured. The expressions of cystathionine-γ-lyase (CSE), Bax and Bcl-2, caspase-3, phospho-endothelial nitric oxide synthase and the mitochondrial NOX4 and cytochrome c were analyzed by Western blotting. The results showed the cardiac dysfunction, the ultrastructural changes, and the apoptotic rate increase in the HHcy rat hearts. In the primary neonatal rat cardiomyocytes of HHcy group, ROS production was increased markedly, whereas the expression of CSE was decreased. However, treatment with NaHS significantly improved the HHcy rat hearts function, the ultrastructural changes, and decreased the levels of ROS in the primary neonatal rat cardiomyocytes administrated with HHcy group. Furthermore, NaHS down-regulated the expression of mitochondrial NOX4 and caspase-3 and Bax and inhibited the release of cytochrome c from mitochondria. In conclusion, H2S is involved in the attenuation of HHcy myocardial injury through the protection of cardiac mitochondria.

  17. Protective effects of emulsified isoflurane after myocardial ischemia-reperfusion injury and its mechanism in rabbits

    Institute of Scientific and Technical Information of China (English)

    RAO Yan; WANG Yan-lin; CHEN Yong-quan; ZHANG Wen-sheng; LIU Jin

    2009-01-01

    Objective: To evaluate the protective effects of 8% emulsified isoflurane after myocardial ischemia-reperfusion injury and its mechanism in rabbits.Methods: Twenty-four male adult New Zealand white rabbits were anesthetized with intravenous injection of 30 mg/kg pentobarbital followed by 5 mg·kg-1·h-1 infusion. All rabbits were subjected to 30 minutes of left anterior de-scending coronary artery (LAD) occlusion and 3 hours of subsequent reperfusion. Before LAD occlusion, the rabbits were randomly allocated into three groups for precondi-tioning treatment (eight for each group). The control group (C group) received intravenously 0.9% NaCl for 30 minutes. The emulsified isoflurane group (EI group) received 8% emulsified isoflurane intravenously till 0.64% end-tidal con-centration for 30 minutes that was followed by a 15-minute washout period. The Intralipid group (IN group) received 30% Intralipid for 30 minutes. The infarcted area, plasma malondialdehyde (MDA) content, superoxide dismutase activity (SOD) and nitrite concentration after 3-hour myo-cardial perfusion were recorded simultaneously.Results: For the myocardial ischemia-reperfusion in-jury animals, the infarcted size in the EI group was signifi-cantly reduced (91.9%±8%) as compared with control group (39%±6%,t=5.19, P<0.01). The plasma SOD activity and nitrite concentration in EI group were significantly higher than those in control group (t=2.82, t=8.46, P<0.05), but MDA content was lower in EI group than that in control group (t=2.56, P<0.05).Conclusions: The results indicate that emulsified isoflurane has a cardioprotection effect against ischemia-reperfusion injury. This beneficial effect of emulsified isoflurane is probably through NO release and consequently by increase in autioxidation of myocardium.

  18. The role and modulation of autophagy in experimental models of myocardial ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Carol Chen-Scarabelli; Richard Knight; Pratik R Agrawal; Louis Saravolatz; Cadigia Abuniat; Gabriele Scarabelli; Anastasis Stephanou; Leena Loomba; Jagat Narula; Tiziano M Scarabelli

    2014-01-01

    A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion (I/R) injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin (mTOR) inhibitors, adenosine monophosphate-activated protein kinase (AMPK) modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.

  19. Endogenous and natural complement inhibitor attenuates myocardial injury and arterial thrombogenesis

    DEFF Research Database (Denmark)

    Pavlov, Vasile I; Skjoedt, Mikkel-Ole; Siow Tan, Ying

    2012-01-01

    complement activation in vitro also could be an in vivo regulator by attenuating myocardial schema/reperfusion injury and thrombogenesis when used at pharmacological doses in wild-type mice. METHODS AND RESULTS: In 2 mouse models, MAP-1 preserves cardiac function, decreases infarct size, decreases C3...... deposition, inhibits MBL deposition, and prevents thrombogenesis. Furthermore, we demonstrate that MAP-1 displaces MBL/ficolin-associated serine protease (MASP)-1, MASP-2, and MASP-3 from the MBL complex. CONCLUSIONS: Our results suggest that the natural, endogenous inhibitor MAP-1 effectively inhibits...

  20. Cardioprotective Effect of Aloe vera Biomacromolecules Conjugated with Selenium Trace Element on Myocardial Ischemia-Reperfusion Injury in Rats.

    Science.gov (United States)

    Yang, Yang; Yang, Ming; Ai, Fen; Huang, Congxin

    2017-06-01

    The present study was undertaken to evaluate the cardioprotection potential and underlying molecular mechanism afforded by a selenium (Se) polysaccharide (Se-AVP) from Aloe vera in the ischemia-reperfusion (I/R) model of rats in vivo. Myocardial I/R injury was induced by occluding the left anterior descending coronary artery (LAD) for 30 min followed by 2-h continuous reperfusion. Pretreatment with Se-AVP (100, 200, and 400 mg/kg) attenuated myocardial damage, as evidenced by reduction of the infarct sizes, increase in serum and myocardial endogenous antioxidants (superoxide dismutase (SOD), glutathione peroxidase (GSH), and catalase (CAT)), and decrease in the malondialdehyde (MDA) level in the rats suffering I/R injury. This cardioprotective activity afforded by Se-AVP is further supported by the decreased levels of cardiac marker enzymes creatine kinase (CK) and lactate dehydrogenase (LDH), as well as the rise of myocardial Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase activities in I/R rats. Additionally, cardiomyocytic apoptosis was measured by terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) staining and the result showed that the percent of TUNEL-positive cells in myocardium of Se-AVP-treated groups was lower than I/R rats. In conclusion, we clearly demonstrated that Se-AVP had a protective effect against myocardial I/R injury in rats by augmenting endogenous antioxidants and protecting rat hearts from oxidative stress-induced myocardial apoptosis.

  1. Protective Effects of Elaeagnus angustifolia Leaf Extract against Myocardial Ischemia/Reperfusion Injury in Isolated Rat Heart

    Directory of Open Access Journals (Sweden)

    Binsheng Wang

    2014-01-01

    Full Text Available The purpose of this study is to clarify the cardioprotective property of the aqueous extract of Elaeagnus angustifolia L. leaf (EA against myocardial ischemia/reperfusion injury in isolated rat heart. The myocardial ischemia/reperfusion (I/R injury model of isolated rat heart was set up by the use of improved Langendorff retrograde perfusion technology. Compared with the ischemia/reperfusion (I/R group, the aqueous extract of Elaeagnus angustifolia L. leaf (0.5 mg/mL, 1.0 mg/mL pretreatment markedly improved the coronary flow (CF and raised left ventricular developed pressure (LVDP and maximum rise/down velocity (±dp/dtmax. The infarct size of the EA-treated hearts was smaller than that of I/R group. After treatment with EA, the superoxide dismutase (SOD activity increased; malondialdehyde (MDA and protein carbonyl content reduced more obviously (P<0.01 than that of I/R injury myocardial tissue. Conclusion. Results from the present study showed that the aqueous extract of Elaeagnus angustifolia L. leaf has obvious protective effects on myocardial I/R injury, which may be related to the improvement of myocardial oxidative stress states.

  2. Ethyl pyruvate reduces myocardial ischemia and reperfusion injury by inhibiting high mobility group box 1 protein in rats.

    Science.gov (United States)

    Hu, Xiaorong; Cui, Bo; Zhou, Xiaoya; Xu, Changwu; Lu, Zhibing; Jiang, Hong

    2012-01-01

    High mobility group box 1 protein (HMGB1) plays an important role in myocardial ischemia and reperfusion (I/R) injury. Ethyl pyruvate (EP), a potent reactive oxygen species scavenger, has been reported to inhibit myocardial apoptosis and reduce myocardial I/R injury. The aim of this study was to investigate the mechanism by which EP reduces myocardial I/R injury in rats. Anesthetized male rats were once treated with EP (50 mg/kg, i.p.) before ischemia, and then subjected to ischemia for 30 min followed by reperfusion for 4 h. Lactate dehydrogenase (LDH), creatine kinase (CK), malondialdehyde (MDA), superoxide dismutase (SOD) activity and infarct size were measured. HMGB1 expression was assessed by immunoblotting. The results showed that pretreatment of EP (50 mg/kg) could significantly reduce the infarct size and the levels of LDH and CK after 4 h reperfusion (all PR. The present study suggested that ethyl pyruvate could attenuate myocardial I/R injury by inhibiting HMGB1 expression.

  3. Traditional Chinese Medicine Shuang Shen Ning Xin Attenuates Myocardial Ischemia/Reperfusion Injury by Preserving of Mitochondrial Function

    Directory of Open Access Journals (Sweden)

    Xueli Li

    2014-01-01

    Full Text Available To investigate the potential cardioprotective effects of Shuang Shen Ning Xin on myocardial ischemia/reperfusion injury. Wistar rats were treated with trimetazidine (10 mg/kg/day, ig, Shuang Shen Ning Xin (22.5, 45 mg/kg/day, ig, or saline for 5 consecutive days. Myocardial ischemia/reperfusion injury was induced by ligation of the left anterior descending coronary artery for 40 min and reperfusion for 120 min on the last day of administration. It is found that Shuang Shen Ning Xin pretreatment markedly decreased infarct size and serum LDH levels, and this observed protection was associated with reduced myocardial oxidative stress and cardiomyocyte apoptosis after myocardial ischemia/reperfusion injury. In addition, further studies on mitochondrial function showed that rats treated with Shuang Shen Ning Xin displayed decreased mitochondrial swelling and cytosolic cytochrome c levels, which were accompanied by a preservation of complex I activities and inhibition of mitochondrial permeability transition. In conclusion, the mitochondrial protective effect of Shuang Shen Ning Xin could be a new mechanism, by which Shuang Shen Ning Xin attenuates myocardial ischemia/reperfusion injury.

  4. Trousseau’s Syndrome, a Previously Unrecognized Condition in Acute Ischemic Stroke Associated With Myocardial Injury

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    Charlotte Thalin MD

    2014-06-01

    Full Text Available Trousseau’s syndrome is a well-known malignancy associated hypercoagulative state leading to venous or arterial thrombosis. The pathophysiology is however poorly understood, although multiple mechanisms are believed to be involved. We report a case of Trousseau’s syndrome resulting in concomitant cerebral and myocardial microthrombosis, presenting with acute ischemic stroke and markedly elevated plasma troponin T levels suggesting myocardial injury. Without any previous medical history, the patient developed multiple cerebral infarctions and died within 11 days of admission. The patient was postmortem diagnosed with an advanced metastatic adenocarcinoma of the prostate with disseminated cerebral, pulmonary, and myocardial microthrombosis. Further analyses revealed, to the best of our knowledge for the first time in stroke patients, circulating microvesicles positive for the epithelial tumor marker CK18 and citrullinated histone H3 in thrombi, markers of the recently described cancer-associated procoagulant DNA-based neutrophil extracellular traps. We also found tissue factor, the main in vivo initiator of coagulation, both in thrombi and in metastases. Troponin elevation in acute ischemic stroke is common and has repeatedly been associated with an increased risk of mortality. The underlying pathophysiology is however not fully clarified, although a number of possible explanations have been proposed. We now suggest that unexplainable high levels of troponin in acute ischemic stroke deserve special attention in terms of possible occult malignancy.

  5. Myocardial disease

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970309 Myocardial injury of Keshan disease andapoptosis. ZHONG Xuekuan(钟学宽), et al. KeshanDis Instit, Harbin Med Univ, Harbin, 150086. Chin JEndemiol 1997, 16(2): 81-82. Objective: To discuss the relationship between my-ocardial injury Of Keshan disease and apoptosis. Meth-

  6. No evidence of sustained myocardial injury following an Ironman distance triathlon.

    Science.gov (United States)

    La Gerche, A; Boyle, A; Wilson, A M; Prior, D L

    2004-01-01

    We aimed to determine whether an Ironman distance triathlon resulted in sustained myocardial injury detected by electrocardiography, biochemical markers or echocardiographic assessment of left ventricular systolic and diastolic function. Electrocardiograms, blood for analysis of creatine kinase (CK) and its MB fraction, cardiac troponin I (cTnI) and echocardiograms were obtained in 15 male athletes prior to and at a mean of 4.7 days after competing in the Australian Ironman Triathlon. Regional wall motion scores, left ventricular ejection fraction (LVEF) and mitral inflow parameters were determined from the echocardiograms by a blinded investigator. Levels of cTnI were undetectable in all athletes and total CK was mildly elevated in 7/15 athletes prior to the event. Baseline wall motion, ejection fraction and diastolic filling were normal in all athletes. CK levels were increased post-race (p < 0.05) with a mean post-race level of 451U/l. Levels of cTnI were undetectable post-race in 14 athletes with a level of 0.9 microg/l recorded in one athlete, although all were within the laboratory's normal range for the assay. Mitral inflow parameters and LVEF did not change post-race and regional wall motion was normal in 14 of 15 athletes. Regional wall motion abnormalities detected in 1 athlete had resolved by 25 days post-race. These findings indicate that ultraendurance exercise does not result in sustained myocardial injury in this group of elite athletes.

  7. Phenylephrine postconditioning increases myocardial injury: Are alpha-1 sympathomimetic agonist cardioprotective?

    Directory of Open Access Journals (Sweden)

    Iordanis Mourouzis

    2014-01-01

    Full Text Available Objective: We studied effects of phenylephrine (PHE on postischemic functional recovery and myocardial injury in an ischemia-reperfusion (I-R experimental model. Materials and Methods: Rat hearts were Langendorff-perfused and subjected to 30 min zero-flow ischemia (I and 60 min reperfusion (R. During R PHE was added at doses of 1 μM (n = 10 and 50 μM (n = 12. Hearts (n = 14 subjected to 30 and 60 min of I-R served as controls. Contractile function was assessed by left ventricular developed pressure (LVDP and the rate of increase and decrease of LVDP; apoptosis by fluorescent imaging targeting activated caspase-3, while myocardial injury by lactate dehydrogenase (LDH released during R. Activation of kinases was measured at 5, 15, and 60 min of R using western blotting. Results: PHE did not improve postischemic contractile function. PHE increased LDH release (IU/g; 102 ± 10.4 (Mean ± standard error of mean control versus 148 ± 14.8 PHE (1, and 145.3 ± 11 PHE (50 hearts, (P < 0.05. PHE markedly increased apoptosis. Molecular analysis showed no effect of PHE on the activation of proapoptotic c-Jun N-terminal kinase signaling; a differential pattern of p38 mitogen activated protein kinase (MAPK activation was found depending on the PHE dose used. With 1 μM PHE, p-p38/total-p38 MAPK levels at R were markedly increased, indicating its detrimental effect. With PHE 50 μM, no further changes in p38 MAPK were seen. Activation of Akt kinase was decreased implying involvement of different mechanisms in this response. Conclusions: PHE administration during reperfusion does not improve postischemic recovery due to exacerbation of myocardial necrosis and apoptosis. This finding may be of clinical and therapeutic relevance.

  8. [Pulsed electric fields inhibit tumor growth but induce myocardial injury of melanoma-bearing mice].

    Science.gov (United States)

    Pan, Fengying; Wu, Sha; Wang, Xiaoxu; Zhang, Xiaogang

    2016-07-01

    Objective To investigate the tumor inhibiting effect of pulsed electric fields (PEFs) on melanoma-bearing mice, and understand its influence on myocardial cells and cardial electrical activity. Methods The melanoma models of the BALB/c mice were established by subcutaneously injecting B16 melanoma cells. These mice were randomly divided into four groups. The treated groups received pulsed electric stimulation at pulse width of 1, 3, 5 ms, with field strength of 100 V/cm and frequency of 10 Hz for 10 minutes daily in 15 consecutive days. ECG of mice was recorded. Tumor volume was measured with vernier caliper. Morphological changes of tumors were observed by HE staining. The expression of proliferating cell nuclear antigen (PCNA) mRNA was tested by real-time quantitative PCR, and the expression of PCNA protein was detected by immunofluorescence histochemistry. The ultrastructural changes of the cardiac tissues were observed by transmission electron microscopy (TEM). The serum levels of cardial troponin T (cTnT) and creatine kinase isoenzyme MB (CK-MB) were detected by ELISA. Results Compared with the control group, tumor volumes in all treated groups were reduced 7 days after PEFs treatment; more melanin granules in tumor cells were found in the treated groups; the expressions of PCNA mRNA and protein were down-regulated in all treated groups, and there were greater changes in the groups receiving the bigger pulse width. Myocardial injury was found in 3 ms group and 5 ms group, and the expressions of cTnT and CK-MB were significantly higher than those in the control group. Conclusion PEFs can inhibit tumor growth in melanoma-bearing mice. Increase of pulse width will aggravate myocardial injury.

  9. Autophagy protects cardiomyocytes from the myocardial ischaemia-reperfusion injury through the clearance of CLP36

    Science.gov (United States)

    Li, Shiguo; Liu, Chao; Gu, Lei; Wang, Lina; Shang, Yongliang; Liu, Qiong; Wan, Junyi; Shi, Jian; Wang, Fang; Xu, Zhiliang; Ji, Guangju

    2016-01-01

    Cardiovascular disease (CVD) is the leading cause of the death worldwide. An increasing number of studies have found that autophagy is involved in the progression or prevention of CVD. However, the precise mechanism of autophagy in CVD, especially the myocardial ischaemia-reperfusion injury (MI/R injury), is unclear and controversial. Here, we show that the cardiomyocyte-specific disruption of autophagy by conditional knockout of Atg7 leads to severe contractile dysfunction, myofibrillar disarray and vacuolar cardiomyocytes. A negative cytoskeleton organization regulator, CLP36, was found to be accumulated in Atg7-deficient cardiomyocytes. The cardiomyocyte-specific knockout of Atg7 aggravates the MI/R injury with cardiac hypertrophy, contractile dysfunction, myofibrillar disarray and severe cardiac fibrosis, most probably due to CLP36 accumulation in cardiomyocytes. Altogether, this work reveals autophagy may protect cardiomyocytes from the MI/R injury through the clearance of CLP36, and these findings define a novel relationship between autophagy and the regulation of stress fibre in heart. PMID:27512143

  10. Intermedin protects against myocardial ischemia-reperfusion injury in hyperlipidemia rats.

    Science.gov (United States)

    Yang, S M; Liu, J; Li, C X

    2014-10-20

    Hyperlipidemia is a well-established risk factor for the development of coronary atherosclerosis, while intermedin (IMD) has been identified as a novel calcitonin/calcitonin gene-related peptide family member involved in cardiovascular protection. However, whether IMD protects against hyperlipidemia-associated myocardial ischemia/reperfusion (MI/R) injury is unknown. We established a hyperlipidemia model using Sprague-Dawley rats, and created a MI/R condition by ligating the cardiac left circumflex artery. The possible pathophysiological role of IMD and its physiological function in MI/R was further studied. The level of IMD significantly decreased in hyperlipidemia rats (P hyperlipidemia rats compared to the sham-operated rats (P hyperlipidemia rats (P hyperlipidemia-associated MI/R injury. Additional IMD could protect cardiac myocytes against MI/R injury via reduction of apoptosis and inflammation in the hyperlipidemia rat model, and thus, it may play a potential role as a novel therapeutic target for cardiac ischemic injury in hyperlipidemic patients.

  11. Irreversible cycle in linear irreversible thermodynamics

    Science.gov (United States)

    Wang, Xian-Zhi

    2010-10-01

    The reversible Carnot cycle in reversible thermodynamics is composed of two reversible heat exchange processes and two reversible adiabatic processes. We construct an irreversible cycle in linear irreversible thermodynamics by analogy with the reversible Carnot cycle. The irreversible cycle is composed of two linear irreversible heat exchange processes and two linear irreversible adiabatic processes. It is found that the Curzon-Alhborn efficiency can be attained if the power for each of the four linear irreversible processes reaches its maximum. The maximum efficiency is the Carnot efficiency. The strong coupling condition is prerequisite for the respective attainment of the Curzon-Alhborn efficiency and the Carnot efficiency.

  12. Ginsenoside Rb1 Preconditioning Enhances eNOS Expression and Attenuates Myocardial Ischemia/Reperfusion Injury in Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Rui Xia

    2011-01-01

    Full Text Available Diabetes mellitus is associated with decreased NO bioavailability in the myocardium. Ginsenoside Rb1 has been shown to confer cardioprotection against ischemia reperfusion injury. The aim of this study was to investigate whether Ginsenoside Rb1 exerts cardioprotective effects during myocardial ischemia-reperfusion in diabetic rats and whether this effect is related to increase the production of NO via enhancing eNOS expression in the myocardium. The myocardial I/R injury were induced by occluding the left anterior descending artery for 30 min followed by 120 min reperfusion. An eNOS inhibitor L-NAME or Rb1 were respectively administered 25 min or 10 min before inducing ischemia. Ginsenoside Rb1 preconditioning reduced myocardial infarct size when compared with I/R group. Ginsenoside Rb1 induced myocardial protection was accompanied with increased eNOS expression and NO concentration and reduced plasma CK and LDH (P<0.05. Moreover, the myocardial oxidative stress and tissue histological damage was attenuated by Ginsenoside Rb1 (P<0.05. L-NAME abolished the protective effects of Ginsenoside Rb1. It is concluded that Ginsenoside Rb1 protects against myocardium ischemia/reperfusion injury in diabetic rat by enhancing the expression of eNOS and increasing the content of NO as well as inhibiting oxidative stress.

  13. Protective effect of bradykinin antagonist Hoe-140 during in vivo myocardial ischemic-reperfusion injury in the cat.

    Science.gov (United States)

    Kumari, Rashmi; Maulik, Mohua; Manchanda, Subhash Chandra; Maulik, Subir Kumar

    2003-10-15

    The effect of icatibant (Hoe-140), a selective bradykinin receptor (B(2)) antagonist on myocardial ischemic-reperfusion injury was studied in open chest barbiturate anaesthetized cats. The left anterior descending coronary artery was occluded for 15 min, followed by 60 min of reperfusion. Saline or icatibant (200 microg/kg) was administered intravenously slowly over 2 min, 5 min before reperfusion. In the saline-treated group, myocardial ischemic-reperfusion injury was evidenced by depressed MAP, depressed peak positive and negative dP/dt and elevated left ventricular end-diastolic pressure and enhanced oxidative stress [elevated plasma thiobarbituric acid reactive substances (TBARS; a marker for lipid peroxidation), depressed myocardial GSH (reduced glutathione), superoxide dismutase (SOD), catalase] and depletion of adenosine triphosphate (ATP) along with rise in plasma creatine phosphokinase (CPK). Administration of icatibant resulted in complete hemodynamic recovery together with repletion of ATP and reduction in plasma TBARS without any significant change in myocardial SOD, catalase and GSH. The results of the present study suggest a protective role of icatibant in myocardial ischemic-reperfusion injury.

  14. Cardioprotective effect of the Hibiscus rosa sinensis flowers in an oxidative stress model of myocardial ischemic reperfusion injury in rat

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    Krishnamoorthy Karthikeyan K

    2006-09-01

    Full Text Available Abstract Background The present study investigates the cardioprotective effects of Hibiscus rosa sinensis in myocardial ischemic reperfusion injury, particularly in terms of its antioxidant effects. Methods The medicinal values of the flowers of Hibiscus rosa sinensis (Chinese rose have been mentioned in ancient literature as useful in disorders of the heart. Dried pulverized flower of Hibiscus rosa sinensis was administered orally to Wistar albino rats (150–200 gms in three different doses [125, 250 and 500 mg/kg in 2% carboxy methyl cellulose (CMC], 6 days per week for 4 weeks. Thereafter, rats were sacrificed; either for the determination of baseline changes in cardiac endogenous antioxidants [superoxide dismutase, reduced glutathione and catalase] or the hearts were subjected to isoproterenol induced myocardial necrosis. Results There was significant increase in the baseline contents of thiobarbituric acid reactive substances (TBARS [a measure of lipid per oxidation] with both doses of Hibiscus Rosa sinensis. In the 250 mg/kg treated group, there was significant increase in superoxide dismutase, reduced glutathione, and catalase levels but not in the 125 and 500 mg/kg treated groups. Significant rise in myocardial thiobarbituric acid reactive substances and loss of superoxide dismutase, catalase and reduced glutathione (suggestive of increased oxidative stress occurred in the vehicle treated hearts subjected to in vivo myocardial ischemic reperfusion injury. Conclusion It may be concluded that flower of Hibiscus rosa sinensis (250 mg/kg augments endogenous antioxidant compounds of rat heart and also prevents the myocardium from isoproterenol induced myocardial injury.

  15. Effects of glycyl-glutamine dipeptide supplementation on myocardial damage and cardiac function in rats after severe burn injury.

    Science.gov (United States)

    Zhang, Yong; Yan, Hong; Lv, Shang-Gun; Wang, Lin; Liang, Guang-Ping; Wan, Qian-Xue; Peng, Xi

    2013-01-01

    Glutamine decreases myocardial damage in ischemia/reperfusion injury. However, the cardioprotective effect of glutamine after burn injury remains unclear. Present study was to explore the protective effect of glycyl-glutamine dipeptide on myocardial damage in severe burn rats. Seventy-two Wistar rats were randomly divided into three groups: normal control (C), burned control (B) and glycyl-glutamine dipeptide-treated (GG) groups. B and GG groups were inflicted with 30% total body surface area of full thickness burn. The GG group was given 1.5 g/kg glycyl-glutamine dipeptide per day and the B group was given the same dose of alanine via intraperitoneal injection for 3 days. The serum CK, LDH, AST, and, blood lactic acid levels, as well as the myocardium ATP and GSH contents, were measured. The indices of cardiac contractile function and histopathological change were analyzed at 12, 24, 48, and 72 post-burn hours (PBH). The serum CK, LDH, AST and blood lactic acid levels increased, and the myocardium ATP and GSH content decreased in both burned groups. Compared with B group, the CK, LDH, AST and blood lactic acid levels reduced, myocardium ATP and GSH content increased in GG group. Moreover, the inhibition of cardiac contractile function and myocardial histopathological damage were reduced significantly in GG group. We conclude that myocardial histological structure and function were damaged significantly after burn injury, glycyl-glutamine dipeptide supplementation is beneficial to myocardial preservation by improving cardiocyte energy metabolism, increasing ATP and glutathione synthesis.

  16. Effects of N-n-butyl Haloperidol Iodide on Myocardial Ischemia/Reperfusion Injury and Egr-1 Expression in Rat

    Institute of Scientific and Technical Information of China (English)

    Yan-Mei ZHANG; Gang-Gang SHI; Zhao TANG; Jin-Hong ZHENG; Wei-Qiu LI; Fu-Xiao GUO; Qiang-Yong JIA

    2006-01-01

    We have previously shown that N-n-butyl haloperidol iodide (F2) derived from haloperidol reduces ischemia/reperfusion-induced myocardial injury by blocking intracellular Ca2+ overload. This study tested the hypothesis that cardio-protection with F2 is associated with an attenuation in the expression of early growth response gene 1 (Egr-1). In an in vivo rat model of 60 min coronary occlusion followed by 180 min of reperfusion, treatment with F2 significantly reduced myocardial injury evidenced by the reduction in release of plasma creatine kinase, myocardial creatine kinase isoenzyme and lactate dehydrogenase. In cultured neonatal rat cardiomyocytes of hypoxia for 3 h and reoxygenation for 1 h, F2 treatment attenuated necrotic and apoptotic cell death, as demonstrated by electron microscopy. Concomitant with cardio-protection by F2, the increased expression levels of Egr-1 mRNA and proteinwere significantly reduced in myocardial tissue and cultured cardiomyocytes as detected by reverse transcription-polymerase chain reaction, immunohistochemistry and immunocytochemistry. In conclusion, these results suggest that the protective effect of F2 on ischemia/reperfusion- or hypoxia/reoxygenation-induced myocardial injury might be partly mediated by downregulating Egr-1 expression.

  17. Association of serum HMGB2 level with MACE at 1 mo of myocardial infarction: Aggravation of myocardial ischemic injury in rats by HMGB2 via ROS.

    Science.gov (United States)

    Liu, Zhu Hui; Dai, Dao Peng; Ding, Feng Hua; Pan, Wen Qi; Fang, Yue Hua; Zhang, Qi; Li, Man; Yang, Ping; Wang, Xiao Qun; Shen, Ying; Wang, Ling Jie; Yan, Xiao Xiang; He, Yu Hu; Yang, Ke; Zhang, Rui Yan; Shen, Wei Feng; Chen, Ying; Lu, Lin

    2017-03-01

    High-mobility group box (HMGB) family is related to inflammatory diseases. We investigated whether serum HMGB2 levels are related to myocardial infarction (MI) severity and major adverse cardiac events (MACE) during MI. We included 432 consecutive patients with ST-segment elevation myocardial infarction and 312 controls. Serum HMGB2 levels were significantly higher in MI patients than in controls. Increased HMGB2 levels were associated with MACE and negatively with ejection fraction in MI patients. HMGB2 was an independent determinant of MACE in logistic regression analysis. HMGB2 protein (10 μg) or saline was injected intramyocardially in MI rats, with or without coadministration of the NADPH oxidase inhibitor apocynin. After 72 h, pathological, echocardiographic, and hemodynamic examinations showed that HMGB2 increased infarct size and worsened cardiac function in MI rats. Moreover, HMGB2 administration enhanced reactive oxygen species (ROS) production, cell apoptosis, inflammation, and autophagosome clearance impairment, which were attenuated by coadministration of apocynin or knock down of receptor for advanced glycation end products (RAGE). In conclusion, increased serum HMGB2 levels are associated with MI severity and MACE at 1 mo. HMGB2 promotes myocardial ischemic injury in rats and hypoxic H9C2 cell damage via ROS provoked by RAGE.NEW & NOTEWORTHY We demonstrate that serum high-mobility group box 2 is associated with major adverse cardiac events at 1 mo in myocardial infarction patients. Mechanistically, high-mobility group box 2 promotes reactive oxygen species production via receptor for advanced glycation end products signaling in ischemic myocardium, thereby aggravating cell apoptosis, inflammation, and autophagosome clearance impairment. This study reveals that high-mobility group box 2 is a novel factor enhancing ischemic injury in myocardial infarction. Copyright © 2017 the American Physiological Society.

  18. Protective Effect of Adansonia digitata against Isoproterenol-Induced Myocardial Injury in Rats.

    Science.gov (United States)

    Ghoneim, Mona A M; Hassan, Amal I; Mahmoud, Manal G; Asker, Mohsen S

    2016-01-01

    The baobab fruit (Adansonia digitata) was analyzed for proximate composition, amino acids, and minerals. The fruit pulp was found to be a good source of carbohydrates, proteins, phenols, and substantial quantities of K, Ca, and Mg. Amino acid analyses revealed high glutamic and aspartic acid, but the sulfur amino acids were the most limited. The present study was designed to investigate the role of Adansonia digitata (Baobab fruit pulp) against isoproterenol induced myocardial oxidative stress in experimental rats by demonstrating the changes in tissue cardiac markers, some antioxidant enzymes, interleukin-1 β (IL-1 β), monocyte chemoattractant protein-1(MCP-1), myeloperoxidase (MPO), Collagen-1, galectin-3, and serum corticosterone. The activities of enzymatic antioxidant glutathione peroxidase (GPX) and non-enzymatic antioxidant reduced glutathione (GSH) in the heart tissue; additionally, histopathological examination of the heart was estimated. Male albino rats were randomly divided into four groups of ten animals each. Group I served as normal control animal. Group II animals received isoproterenol (ISP) (85 mg/kg body weight intraperitonealy (i.p.) to develop myocardial injury. Group III were myocardial oxidative animals treated with Baobab fruit pulp (200 µg/rats/day) for 4 weeks. Group IV received Baobab fruit pulp only. The data suggested an isoproterenol increase in levels of cardiac marker enzymes [creatine kinase MB (CK- MB), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST)], IL-1ß, MCP-1, MPO, Collagen, and galectin-3, with concomitant decrease in the activities GPX and GSH in heart tissue as well as corticosterone in serum. Baobab fruit pulp brings all the parameters to near normal level in ISP-induced myocardial infarction in rats. Histopathological examination of heart tissue of ISP-administered model rat showed infiltration of inflammatory cells and congestion in the blood vessels. However, treatment with Baobab fruit pulp (200

  19. Cardiovascular magnetic resonance by non contrast T1-mapping allows assessment of severity of injury in acute myocardial infarction

    Science.gov (United States)

    2012-01-01

    Background Current cardiovascular magnetic resonance (CMR) methods, such as late gadolinium enhancement (LGE) and oedema imaging (T2W) used to depict myocardial ischemia, have limitations. Novel quantitative T1-mapping techniques have the potential to further characterize the components of ischemic injury. In patients with myocardial infarction (MI) we sought to investigate whether state-of the art pre-contrast T1-mapping (1) detects acute myocardial injury, (2) allows for quantification of the severity of damage when compared to standard techniques such as LGE and T2W, and (3) has the ability to predict long term functional recovery. Methods 3T CMR including T2W, T1-mapping and LGE was performed in 41 patients [of these, 78% were ST elevation MI (STEMI)] with acute MI at 12-48 hour after chest pain onset and at 6 months (6M). Patients with STEMI underwent primary PCI prior to CMR. Assessment of acute regional wall motion abnormalities, acute segmental damaged fraction by T2W and LGE and mean segmental T1 values was performed on matching short axis slices. LGE and improvement in regional wall motion at 6M were also obtained. Results We found that the variability of T1 measurements was significantly lower compared to T2W and that, while the diagnostic performance of acute T1-mapping for detecting myocardial injury was at least as good as that of T2W-CMR in STEMI patients, it was superior to T2W imaging in NSTEMI. There was a significant relationship between the segmental damaged fraction assessed by either by LGE or T2W, and mean segmental T1 values (P myocardial damage. T1-mapping might become an important complementary technique to LGE and T2W for identification of reversible myocardial injury and prediction of functional recovery in acute MI. PMID:22309452

  20. Tramadol Alleviates Myocardial Injury Induced by Acute Hindlimb Ischemia Reperfusion in Rats

    Directory of Open Access Journals (Sweden)

    Hamed Ashrafzadeh Takhtfooladi

    2015-01-01

    Full Text Available Background: Organ injury occurs not only during periods of ischemia but also during reperfusion. It is known that ischemia reperfusion (IR causes both remote organ and local injuries. Objective: This study evaluated the effects of tramadol on the heart as a remote organ after acute hindlimb IR. Methods: Thirty healthy mature male Wistar rats were allocated randomly into three groups: Group I (sham, Group II (IR, and Group III (IR + tramadol. Ischemia was induced in anesthetized rats by left femoral artery clamping for 3 h, followed by 3 h of reperfusion. Tramadol (20 mg/kg, intravenous was administered immediately prior to reperfusion. At the end of the reperfusion, animals were euthanized, and hearts were harvested for histological and biochemical examination. Results: The levels of superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPx were higher in Groups I and III than those in Group II (p < 0.05. In comparison with other groups, tissue malondialdehyde (MDA levels in Group II were significantly increased (p < 0.05, and this increase was prevented by tramadol. Histopathological changes, including microscopic bleeding, edema, neutrophil infiltration, and necrosis, were scored. The total injuryscore in Group III was significantly decreased (p < 0.05 compared with Group II. Conclusion: From the histological and biochemical perspectives, treatment with tramadol alleviated the myocardial injuries induced by skeletal muscle IR in this experimental model.

  1. Tramadol Alleviates Myocardial Injury Induced by Acute Hindlimb Ischemia Reperfusion in Rats

    Energy Technology Data Exchange (ETDEWEB)

    Takhtfooladi, Hamed Ashrafzadeh; Asl, Adel Haghighi Khiabanian [Department of Pathobiology, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Shahzamani, Mehran [Department of Cardiovascular Surgery, Isfahan University of Medical Sciences, Tehran (Iran, Islamic Republic of); Takhtfooladi, Mohammad Ashrafzadeh, E-mail: dr-ashrafzadeh@yahoo.com [Young Researchers and Elites Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Allahverdi, Amin [Department of Surgery, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Khansari, Mohammadreza [Department of Physiology, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2015-08-15

    Organ injury occurs not only during periods of ischemia but also during reperfusion. It is known that ischemia reperfusion (IR) causes both remote organ and local injuries. This study evaluated the effects of tramadol on the heart as a remote organ after acute hindlimb IR. Thirty healthy mature male Wistar rats were allocated randomly into three groups: Group I (sham), Group II (IR), and Group III (IR + tramadol). Ischemia was induced in anesthetized rats by left femoral artery clamping for 3 h, followed by 3 h of reperfusion. Tramadol (20 mg/kg, intravenous) was administered immediately prior to reperfusion. At the end of the reperfusion, animals were euthanized, and hearts were harvested for histological and biochemical examination. The levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were higher in Groups I and III than those in Group II (p < 0.05). In comparison with other groups, tissue malondialdehyde (MDA) levels in Group II were significantly increased (p < 0.05), and this increase was prevented by tramadol. Histopathological changes, including microscopic bleeding, edema, neutrophil infiltration, and necrosis, were scored. The total injuryscore in Group III was significantly decreased (p < 0.05) compared with Group II. From the histological and biochemical perspectives, treatment with tramadol alleviated the myocardial injuries induced by skeletal muscle IR in this experimental model.

  2. Neutrophil accumulation in experimental myocardial infarcts: relation with extent of injury and effect of reperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Chatelain, P.; Latour, J.G.; Tran, D.; de Lorgeril, M.; Dupras, G.; Bourassa, M.

    1987-05-01

    The effects of reperfusion on the myocardial accumulation of neutrophils and their role in the extent of injury were investigated in a canine preparation with a 3 hr coronary occlusion followed by 21 hr of reperfusion. The left anterior descending coronary artery (LAD) was permanently occluded in group 1 and reperfused after 3 hr in four others (groups 2 to 5). All but group 5 received lidocaine (1 mg/min over 8 hr). A critical stenosis was produced and left in place at reperfusion only in group 2. In groups 1 and 2, /sup 111/In-labeled autologous neutrophils were injected at the time of coronary occlusion. Group 4 animals were rendered leukopenic 2 hr before the coronary ligature and throughout the experiment by injection of an antineutrophil rabbit serum. Quantification of the radioactivity by digitized scintigraphy of the heart slices revealed an 80% increase in neutrophil accumulation in the infarct region after reperfusion (group 2) as compared with permanent occlusion (group 1). Gamma counting of myocardial tissue samples showed that the neutrophil accumulation ratio in the subendocardial central zone of the infarct was increased five times by reperfusion, whereas no difference was evident in the subepicardium. Infarct size and myocardial area at risk were not statistically different among the five groups. However LAD flow in the leukopenic group (group 4) was significantly higher 30 min after reperfusion (40.0 +/- 5 ml/min) when compared with the preocclusion value (21.7 +/- 4 ml/min). In contrast, in a parallel experiment without leukopenia (group 3), LAD flow after reperfusion did not differ from the preocclusion value.

  3. Myocardial contrast echocardiography to assess perfusion in a mouse model of ischemia/reperfusion injury

    Science.gov (United States)

    Hossack, John A.; Li, Yinbo; Christensen, Jonathan P.; Yang, Zequan; French, Brent A.

    2004-04-01

    Noninvasive approaches for measuring anatomical and physiological changes resulting from myocardial ischemia / reperfusion injury in the mouse heart have significant value since the mouse provides a practical, low-cost model for modeling human heart disease. In this work, perfusion was assessed before, during and after an induced closed- chest, coronary ischemic event. Ultrasound contrast agent, similar to MP1950, in a saline suspension, was injected via cannulated carotid artery as a bolus and imaged using a Siemens Sequoia 512 scanner and a 15L8 intraoperative transducer operating in second harmonic imaging mode. Image sequences were transferred from the scanner to a PC for analysis. Regions of interest were defined in septal and anterior segments of the myocardium. During the ischemic event, when perfusion was diminished in the anterior segment, mean video intensity in the affected segment was reduced by one half. Furthermore, following reperfusion, hyperemia (enhanced blood flow) was observed in the anterior segment. Specifically, the mean video intensity in the affected segment was increased by approximately 50% over the original baseline level prior to ischemia. Following the approach of Kaul et al., [1], gamma variate curves were fitted to the time varying level of mean video intensity. This foundation suggests the possibility of quantifying myocardial blood flow in ischemic regions of a mouse heart using automated analysis of contrast image data sets. An improved approach to perfusion assessment using the destruction-reperfusion approach [2] is also presented.

  4. Reduction of myocardial ischemia reperfusion injury with regular consumption of grapes.

    Science.gov (United States)

    Cui, Jianhua; Cordis, Gerald A; Tosaki, Arpad; Maulik, Nilanjana; Das, Dipak K

    2002-05-01

    Recently several polyphenolic antioxidants derived from grape seeds and skins have been implicated in cardioprotection. This study was undertaken to determine if the grapes were equally cardioprotective. Sprague Dawley male rats were given (orally) standardized grape extract (SGE) for a period of three weeks. Time-matched control experiments were performed by feeding the animals 45 microg/100 of glucose plus 45 microg/100 g fructose per day for three weeks. After 30 days, rats were sacrificed, hearts excised and perfused via working-mode. Hearts were made ischemic for 30 min followed by two hours of reperfusion. At 100 mg/kg and at 200 mg/kg, SGE provided significant cardioprotection as evidenced by improved post-ischemic ventricular recovery and reduced amount of myocardial infarction. No cardioprotection was apparent when rats were given grape samples at a dose of 50 mg/100 g/day. In vitro studies demonstrated that the SGE could directly scavenge superoxide and hydroxyl radicals which are formed in the ischemic reperfused myocardium. The results demonstrate that the heats of the rats fed SGE reduced myocardial ischemia reperfusion injury by functioning as in vivo antioxidant.

  5. Increased myocardial vulnerability to ischemia-reperfusion injury in the presence of left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Mølgaard, Søren; Faricelli, Barbara; Salomonsson, Max

    2016-01-01

    Objective: Despite its high prevalence among patients suffering myocardial infarction, the significance of left ventricle hypertrophy for infarct size is not known. We asked whether infarct size might be increased by this condition, and whether any such increase might be associated with an increa......Objective: Despite its high prevalence among patients suffering myocardial infarction, the significance of left ventricle hypertrophy for infarct size is not known. We asked whether infarct size might be increased by this condition, and whether any such increase might be associated...... with an increased mitochondrial damage following coronary occlusion.  Methods: Occlusion of the left descending artery in isolated, perfused hearts of SHR-SP (spontaneously hypertensive rat stroke-prone) (left ventricular hypertrophy) or Wistar-Kyoto (WKY) (control) rats was used, followed by reperfusion.......  Conclusion: Hearts from hypertensive (SHR-SP) rats with left ventricle hypertrophy appeared more vulnerable to ischemia-reperfusion injury, as supported by a more profound infarct development and an earlier loss of postconditioning by Exe-4. Mitochondrial complexes III and IV were identified among possible...

  6. What Is the Meaning of Increased Myocardial Injury Enzymes during Hemodialysis? A Tissue Doppler Imaging Study.

    Science.gov (United States)

    Yildiz, Gürsel; Kayataş, Mansur; Candan, Ferhan; Yilmaz, Mehmet Birhan; Zorlu, Ali; Sarikaya, Savaş

    2013-07-01

    Cardiovascular death is decreasing in the general population; however, it appears in still higher rates and even increases gradually in hemodialysis (HD) patients. This situation has led to a debate about cardiovascular adverse effects of HD which lead to significant changes in cardiac and hemodynamic events. It is known that troponins are often elevated in HD patients, and high levels of troponin are associated with increased mortality. Therefore, it is difficult to interpret the value of elevations in chronic kidney disease patients. Echocardiographic and biochemical parameters of 41 patients treated with HD were evaluated before and after a HD session. HD led to an increased heart rate, and tissue Doppler imaging parameters such as early diastolic mitral peak velocity (E)/early diastolic myocardial peak velocity (é) and septal é decreased significantly after HD. HD caused an increase in troponin I, myoglobin and cardiac creatine kinase (CK MB) levels (p = 0.019, p increased levels of cardiac damage markers (group 2) compared to those without increased levels of cardiac damage markers (group 1) in HD. A decrease in LV S' velocity was found to be an independent predictor of an increase of myocardial injury enzymes in HD (odds ratio = 1.099; p = 0.039). We concluded that HD may lead to significant acute stress upon the myocardium.

  7. Lipoxin A4 Preconditioning and Postconditioning Protect Myocardial Ischemia/Reperfusion Injury in Rats

    Directory of Open Access Journals (Sweden)

    Qifeng Zhao

    2013-01-01

    Full Text Available This study aims to investigate the pre- and postconditioning effects of lipoxin A4 (LXA4 on myocardial damage caused by ischemia/reperfusion (I/R injury. Seventy-two rats were divided into 6 groups: sham groups (C1 and C2, I/R groups (I/R1 and I/R2, and I/R plus LXA4 preconditioning and postconditioning groups (LX1 and LX2. The serum levels of IL-1β, IL-6, IL-8, IL-10, TNF-α, and cardiac troponin I (cTnI were measured. The content and the activity of Na+-K+-ATPase as well as the superoxide dismutase (SOD, and malondialdehyde (MDA levels were determined. Along with the examination of myocardium ultrastructure and ventricular arrhythmia scores (VAS, connexin 43 (Cx43 expression were also detected. Lower levels of IL-1β, IL-6, IL-8, TNF-α, cTnI, MDA content, and VAS and higher levels of IL-10, SOD activity, Na+-K+-ATPase content and activity, and Cx43 expression appeared in LX groups than I/R groups. Besides, H&E staining, TEM examination as well as analysis of gene, and protein confirmed that LXA4 preconditioning was more effective than postconditioning in preventing arrhythmogenesis via the upregulation of Cx43. That is, LXA4 postconditioning had better protective effect on Na+-K+-ATPase and myocardial ultrastructure.

  8. Inhibition of Drp1 attenuates mitochondrial damage and myocardial injury in Coxsackievirus B3 induced myocarditis.

    Science.gov (United States)

    Lin, Lin; Zhang, Ming; Yan, Rui; Shan, Hu; Diao, Jiayu; Wei, Jin

    2017-03-11

    Viral myocarditis (VMC) is closely related to apoptosis, oxidative stress, innate immunity, and energy metabolism, which are all linked to mitochondrial dysfunction. A close nexus between mitochondrial dynamics and cardiovascular disease with mitochondrial dysfunction has been deeply researched, but there is still no relevant report in viral myocarditis. In this study, we aimed to explore the role of Dynamin-related protein 1 (Drp1)-linked mitochondrial fission in VMC. Mice were inoculated with the Coxsackievirus B3 (CVB3) and treated with mdivi1 (a Drp1 inhibitor). Protein expression of Drp1 was increased in mitochondria while decreased in cytoplasm and accompanied by excessive mitochondrial fission in VMC mice. In addition, midivi1 treatment attenuate inflammatory cells infiltration in myocardium of the mice, serum Cardiac troponin I (CTnI) and Creatine kinase-MB (CK-MB) level. Mdivi1 also could improved the survival rate of mice and mitochondrial dysfunction reflected as the up-regulated mitochondrial marker enzymatic activities of succinate dehydrogenase (SDH), cytochrome c oxidase (COX) and mitochondrial membrane potential (MMP). At the same time, mdivi1 rescued the body weight loss, myocardial injury and apoptosis of cardiomyocyte. Furthermore, decease in LVEDs and increase in EF and FS were detected by echocardiogram, which indicated the improved myocardial function. Thus, Drp1-linked excessive mitochondrial fission contributed to VMC and midivi1 may be a potential therapeutic approach.

  9. The protective effects of dexmedetomidine on liver injury-induced myocardial ischemia reperfusion.

    Science.gov (United States)

    Erer, D; Ozer, A; Arslan, M; Oktar, G L; Iriz, E; Elmas, C; Zor, M H; Tatar, T; Goktas, G

    2014-01-01

    The aim of this study was to evaluate the effect of dexmedetomidine (100 µg/kg-ip) on liver injury-induced myocardial ischemia and reperfusion (IR) in rats. Twenty-four Wistar Albino rats were separated into four groups. There were four experimental groups (Group C (Control; n = 6), Group IR (ischemia-reperfusion, n = 6), Group D (Dexmedetomidine; n = 6) that underwent left thoracotomy and received ip dexmedetomidine without IR administered via 100 µg/kg ip route 30 minutes before ligating the left coronary artery, and Group IR-D (IR-Dexmedetomidine; n = 6). A small plastic snare was threaded through the ligature and placed in contact with the heart. To produce IR, a branch of the left coronary artery was occluded for 30 min followed by two hours of reperfusion. However, after the above procedure, the coronary artery was not occluded or reperfused in the control rats. At the end of the study, liver tissue was obtained for histochemical and immunohistochemical determination.Some part of tissue samples were stained with Masson-trichrome for the evaluation of ultrastructural changes and inducible nitric oxide synthase (iNOS) expression was evaluated in other part of samples for immunohistochemical examination. Histopathological changes were detected in Group IR when compared with Group C. iNOS expression was found to be increased and stronger particularly in the vascular wall, perisinusoidal space and hepatocytes around vena centralis in this group compared to the control group. Perivascular oedema was detected to be decreased in Group IR-D compared to Group IR. It was also observed that the impairment in the radial arrangement of hepatocytes significantly recovered in Group IR-D. The immunoreactivity was found to be significantly decreased in the assessment of iNOS expression in the same group when compared with Group IR. Administration of dexmedetomidine ameliorates liver injury induced by myocardial ischemia and reperfusion (Fig. 8, Ref. 33).

  10. Sex-dependent effects of chronic psychosocial stress on myocardial sensitivity to ischemic injury.

    Science.gov (United States)

    Rorabaugh, Boyd R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah; Fry, Megan E; Lawson, Joseph D; Stoner, Lauren E; Johnson, Brandon L; Zoladz, Phillip R

    2015-01-01

    Individuals with post-traumatic stress disorder (PTSD) experience many debilitating symptoms, including intrusive memories, persistent anxiety and avoidance of trauma-related cues. PTSD also results in numerous physiological complications, including increased risk for cardiovascular disease (CVD). However, characterization of PTSD-induced cardiovascular alterations is lacking, especially in preclinical models of the disorder. Thus, we examined the impact of a psychosocial predator-based animal model of PTSD on myocardial sensitivity to ischemic injury. Male and female Sprague-Dawley rats were exposed to psychosocial stress or control conditions for 31 days. Stressed rats were given two cat exposures, separated by a period of 10 days, and were subjected to daily social instability throughout the paradigm. Control rats were handled daily for the duration of the experiment. Rats were tested on the elevated plus maze (EPM) on day 32, and hearts were isolated on day 33 and subjected to 20 min ischemia and 2 h reperfusion on a Langendorff isolated heart system. Stressed male and female rats gained less body weight relative to controls, but only stressed males exhibited increased anxiety on the EPM. Male, but not female, rats exposed to psychosocial stress exhibited significantly larger infarcts and attenuated post-ischemic recovery of contractile function compared to controls. Our data demonstrate that predator stress combined with daily social instability sex-dependently increases myocardial sensitivity to ischemic injury. Thus, this manipulation may be useful for studying potential mechanisms underlying cardiovascular alterations in PTSD, as well as sex differences in the cardiovascular stress response.

  11. The effect of Euryale ferox (Makhana), an herb of aquatic origin, on myocardial ischemic reperfusion injury.

    Science.gov (United States)

    Das, Samarjit; Der, Peter; Raychaudhuri, Utpal; Maulik, Nilanjana; Das, Dipak K

    2006-09-01

    Fox nut or gorgon nut (Euryale ferox--Family Nymphaeaceae), popularly known as Makhana, has been widely used in traditional oriental medicine to cure a variety of diseases including kidney problems, chronic diarrhea, excessive leucorrhea and hypofunction of the spleen. Based on the recent studies revealing antioxidant activities of Euryale ferox and its glucosides composition, we sought to determine if Euryale ferox seeds (Makhana) could reduce myocardial ischemic reperfusion injury. Two different models were used: acute model, where isolated rat hearts were preperfused for 15 min with Krebs Henseleit bicarbonate (KHB) buffer containing three different doses of makhana (25, 125 or 250 microg/ml) followed by 30 min of ischemia and 2 h of reperfusion; and chronic model, where rats were given two different doses of makhana (250 and 500 mg/kg/day) for 21 days, after which isolated hearts were subjected to 30 min of ischemia followed by 2 h of reperfusion. In both cases, the hearts of the Makhana treated rats were resistant to ischemic reperfusion injury as evidenced by their improved post-ischemic ventricular function and reduced myocardial infarct size. Antibody array technique was used to identify the cardioprotective proteins. The Makhana-treated hearts had increased amounts of thioredoxin-1 (Trx-1) and thioredoxin-related protein-32 (TRP32) compared to the control hearts. Western blot analysis confirmed increased expression of TRP32 and thioredoxin proteins. In vitro studies revealed that Makhana extracts had potent reactive oxygen species scavenging activities. Taken together, the results of this study demonstrate cardioprotective properties of Makhana and suggest that such cardioprotective properties may be linked with the ability of makhana to induce TRP32 and Trx-1 proteins and to scavenge ROS.

  12. Role of microRNA-195 in cardiomyocyte apoptosis induced by myocardial ischaemia–reperfusion injury

    Indian Academy of Sciences (India)

    Chang-Kui Gao; Hui Liu; Cheng-Ji Cui; Zhao-Guang Liang; Hong Yao; Ye Tian

    2016-03-01

    This study aims to investigate microRNA-195 (miR-195) expression in myocardial ischaemia–reperfusion (I/R) injury and the roles of miR-195 in cardiomyocyte apoptosis though targeting Bcl-2. A mouse model of I/R injury was established. MiR-195 expression levels were detected by real-time quantitative PCR (qPCR), and the cardiomyocyte apoptosis was detected by TUNEL assay. After cardiomyocytes isolated from neonatal rats and transfected with miR-195 mimic or inhibitor, the hypoxia/reoxygenation (H/R) injury model was established. Cardiomyocyte apoptosis and mitochondrial membrane potential were evaluated using flow cytometry. Bcl-2 and Bax mRNA expressions were detected by RT-PCR. Bcl-2, Bax and cytochrome c (Cyt-c) protein levels were determined by Western blot. Caspase-3 and caspase-9 activities were assessed by luciferase assay. Compared with the sham group, miR-195 expression levels and rate of cardiomyocyte apoptosis increased significantly in I/R group (both < 0.05). Compared to H/R + negative control (NC) group, rate of cardiomyocyte apoptosis increased in H/R + miR-195 mimic group while decreased in H/R + miR-195 inhibitor group (both < 0.05). MiR-195 knockdown alleviated the loss of mitochondrial membrane potential ( < 0.05). MiR-195 overexpression decreased Bcl-2 mRNA and protein expression, increased BaxmRNA and protein expression, Cyt-c protein expression and caspase-3 and caspase-9 activities (all < 0.05). While, downregulated MiR-195 increased Bcl-2 mRNA and protein expression, decreased Bax mRNA and protein expression, Cyt-c protein expression and caspase-3 and caspase-9 activities (all < 0.05). Our study identified that miR-195 expression was upregulated in myocardial I/R injury, and miR-195 overexpression may promote cardiomyocyte apoptosis by targeting Bcl-2 and inducing mitochondrial apoptotic pathway.

  13. Activated Notch1 reduces myocardial ischemia reperfusion injury in vitro during ischemic postconditioning by crosstalk with the RISK signaling pathway

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xue-liang; WAN Li; LIU Ji-chun

    2013-01-01

    Background Ischemic postconditioning (IPost),able to significantly attenuate myocardial ischemia reperfusion injury,is dependent on RISK signaling.Studies have shown that Notch signaling repairs damaged myocardium,and this study aimed to investigate the effect of Notch signaling in myocardial IPost.Methods We used H9c2 cells to establish the myocardial IPost and Hypoxia/Reoxygenation (H/R) model in vitro,which were randomly divided into control,H/R,IPost,Hepatocyte growth factor (HGF)+IPost and DAPT+IPost,N1ICD+IPost,miRNA+lPost,and Mock treatment groups.The myocardial cell viability was assessed by MTT,the cell apoptosis was detected using Annexin V/PI double staining and flow cytometry analyses.The expression of N1ICD,Hes1,PTEN Phospho-Akt/Akt,Phospho-GSK-3β/GSK-3β were detected by Western blotting.Finally,we assessed the changes in Ψm using the potential-sensitive dye JC-1 and measured using flow cytometry analyses.Results The Notch1 signaling is activated by HGF and ectopic expression of N1ICD during myocardial IPost,which increased myocardial cell viability,prevented cardiomyocyte apoptosis,and reduced loss of the mitochondrial membrane potential.However,myocardial ischemia reperfusion injury was increased in IPost when Notch1 signaling was inhibited using DAPT or with knockdown by Notch1-miRNA.Western blotting found that PTEN was down-regulated by Hes1 when Notch1 was activated,which consequently promoted Akt and GSK-3β phosphorylation.Conclusions Notch1 crosstalk with RISK signaling may be dependent on PTEN,which plays a cardioprotective role during IPost.This mechanism could provide a promising therapeutic target for the treatment of ischemic heart disease.

  14. Protective effect of dietary n-3 polyunsaturated fatty acids on myocardial resistance to ischemia-reperfusion injury in rats.

    Science.gov (United States)

    Zeghichi-Hamri, Sabrina; de Lorgeril, Michel; Salen, Patricia; Chibane, Mohamed; de Leiris, Joël; Boucher, François; Laporte, François

    2010-12-01

    Dietary n-3 polyunsaturated fatty acids (PUFA) reduce coronary heart disease (CHD) complications, such as chronic arrhythmia and sudden cardiac death. Improved myocardial resistance to ischemia-reperfusion injury results in smaller myocardial infarction, which is a major factor in the occurrence of CHD complications. We hypothesized that a specific dietary fatty acid profile (low in saturated and n-6 PUFA but high in plant and marine n-3 PUFA) may improve myocardial resistance to ischemia-reperfusion injury and reduce infarct size. To test this assumption, we used a well-defined rat model of myocardial infarction. Based on our results, in comparison to a diet that is high in either saturated or n-6 PUFA but poor in plant and marine n-3 PUFA, a diet that is low in saturated fats and n-6 PUFA but rich in plant and marine n-3 PUFA results in smaller myocardial infarct size (P fatty acid composition of plasma, erythrocyte cell membranes, and the phospholipids of myocardial mitochondria. The results show a great accumulation of n-3 PUFA and a parallel decrease in arachidonic acid, the main n-6 PUFA, in plasma, cell membranes, and cardiac mitochondria (P < .0001). We conclude that improved myocardial resistance to ischemia-reperfusion may be one of the critical factors explaining the protective effects of dietary n-3 PUFA against CHD complications in humans. In addition to increasing n-3 PUFA intake, an optimal dietary pattern aimed at reducing cardiovascular mortality should include a reduction of the intake of both saturated and n-6 PUFA.

  15. Cardioprotective Effect of Licochalcone D against Myocardial Ischemia/Reperfusion Injury in Langendorff-Perfused Rat Hearts.

    Directory of Open Access Journals (Sweden)

    Xuan Yuan

    Full Text Available Flavonoids are important components of 'functional foods', with beneficial effects on cardiovascular function. The present study was designed to investigate whether licochalcone D (LD could be a cardioprotective agent in ischemia/reperfusion (I/R injury and to shed light on its possible mechanism. Compared with the I/R group, LD treatment enhanced myocardial function (increased LVDP, dp/dtmax, dp/dtmin, HR and CR and suppressed cardiac injury (decreased LDH, CK and myocardial infarct size. Moreover, LD treatment reversed the I/R-induced cleavage of caspase-3 and PARP, resulting in a significant decrease in proinflammatory factors and an increase in antioxidant capacity in I/R myocardial tissue. The mechanisms underlying the antiapoptosis, antiinflammation and antioxidant effects were related to the activation of the AKT pathway and to the blockage of the NF-κB/p65 and p38 MAPK pathways in the I/R-injured heart. Additionally, LD treatment markedly activated endothelial nitric oxide synthase (eNOS and reduced nitric oxide (NO production. The findings indicated that LD had real cardioprotective potential and provided support for the use of LD in myocardial I/R injury.

  16. Cardioprotective Effects of Salvianolic Acid A on Myocardial Ischemia-Reperfusion Injury In Vivo and In Vitro

    Directory of Open Access Journals (Sweden)

    Huaying Fan

    2012-01-01

    Full Text Available Salvianolic acid A (SAA, one of the major active components of Danshen that is a traditional Chinese medicine, has been reported to possess protective effect in cardiac diseases and antioxidative activity. This study aims to investigate the cardioprotection of SAA in vivo and in vitro using the model of myocardial ischemia-reperfusion in rat and hydrogen peroxide (H2O2-induced H9c2 rat cardiomyoblasts apoptosis. It was found that SAA significantly limited infarct size of ischemic myocardium when given immediately prior to reperfusion. SAA also significantly suppressed cellular injury and apoptotic cell death. Additionally, the results of western blot and phospho-specific antibody microarray analysis showed that SAA could up-regulate Bcl-2 expression and increase the phosphorylation of proteins such as Akt, p42/p44 extracellular signal-related kinases (Erk1/2, and their related effectors. The phosphorylation of those points was related to suppress apoptosis. In summary, SAA possesses marked protective effect on myocardial ischemia-reperfusion injury, which is related to its ability to reduce myocardial cell apoptosis and damage induced by oxidative stress. The protection is achieved via up-regulation of Bcl-2 expression and affecting protein phosphorylation. These findings indicate that SAA may be of value in cardioprotection during myocardial ischemia-reperfusion injury, which provide pharmacological evidence for clinical application.

  17. Cardioprotective Effects of Salvianolic Acid A on Myocardial Ischemia-Reperfusion Injury In Vivo and In Vitro

    Science.gov (United States)

    Fan, Huaying; Yang, Liu; Fu, Fenghua; Xu, Hui; Meng, Qinggang; Zhu, Haibo; Teng, Lirong; Yang, Mingyan; Zhang, Leiming; Zhang, Ziliang; Liu, Ke

    2012-01-01

    Salvianolic acid A (SAA), one of the major active components of Danshen that is a traditional Chinese medicine, has been reported to possess protective effect in cardiac diseases and antioxidative activity. This study aims to investigate the cardioprotection of SAA in vivo and in vitro using the model of myocardial ischemia-reperfusion in rat and hydrogen peroxide (H2O2)-induced H9c2 rat cardiomyoblasts apoptosis. It was found that SAA significantly limited infarct size of ischemic myocardium when given immediately prior to reperfusion. SAA also significantly suppressed cellular injury and apoptotic cell death. Additionally, the results of western blot and phospho-specific antibody microarray analysis showed that SAA could up-regulate Bcl-2 expression and increase the phosphorylation of proteins such as Akt, p42/p44 extracellular signal-related kinases (Erk1/2), and their related effectors. The phosphorylation of those points was related to suppress apoptosis. In summary, SAA possesses marked protective effect on myocardial ischemia-reperfusion injury, which is related to its ability to reduce myocardial cell apoptosis and damage induced by oxidative stress. The protection is achieved via up-regulation of Bcl-2 expression and affecting protein phosphorylation. These findings indicate that SAA may be of value in cardioprotection during myocardial ischemia-reperfusion injury, which provide pharmacological evidence for clinical application. PMID:21789047

  18. Glycyrrhiza glabra protects from myocardial ischemia-reperfusion injury by improving hemodynamic, biochemical, histopathological and ventricular function.

    Science.gov (United States)

    Ojha, Shreesh; Golechha, Mahaveer; Kumari, Santosh; Bhatia, Jagriti; Arya, Dharamvir S

    2013-01-01

    Present study evaluated the cardioprotective effect of Glycyrrhiza glabra against ischemia-reperfusion injury (I-R) induced by ligation of left anterior descending coronary artery (LADCA) in rats. Ligation of LADCA for 45 min followed by 60 min of reperfusion has induced significant (pglabra significantly (pglabra also prevented GSH depletion and inhibited lipid peroxidation in heart. In addition to improving biochemical indices of myocardial function, G. glabra also significantly (pglabra. Taken together, results of the present study clearly suggest the cardioprotective potential of G. glabra against myocardial infarction by amelioration of oxidative stress and favorable modulation of cardiac function.

  19. Targeting TRAF3IP2 by Genetic and Interventional Approaches Inhibits Ischemia/Reperfusion-induced Myocardial Injury and Adverse Remodeling.

    Science.gov (United States)

    Erikson, John M; Valente, Anthony J; Mummidi, Srinivas; Kandikattu, Hemanth Kumar; DeMarco, Vincent G; Bender, Shawn B; Fay, William P; Siebenlist, Ulrich; Chandrasekar, Bysani

    2017-02-10

    Re-establishing blood supply is the primary goal for reducing myocardial injury in subjects with ischemic heart disease. Paradoxically, reperfusion results in nitroxidative stress and a marked inflammatory response in the heart. TRAF3IP2 (TRAF3 Interacting Protein 2; previously known as CIKS or Act1) is an oxidative stress-responsive cytoplasmic adapter molecule that is an upstream regulator of both IκB kinase (IKK) and c-Jun N-terminal kinase (JNK), and an important mediator of autoimmune and inflammatory responses. Here we investigated the role of TRAF3IP2 in ischemia/reperfusion (I/R)-induced nitroxidative stress, inflammation, myocardial dysfunction, injury, and adverse remodeling. Our data show that I/R up-regulates TRAF3IP2 expression in the heart, and its gene deletion, in a conditional cardiomyocyte-specific manner, significantly attenuates I/R-induced nitroxidative stress, IKK/NF-κB and JNK/AP-1 activation, inflammatory cytokine, chemokine, and adhesion molecule expression, immune cell infiltration, myocardial injury, and contractile dysfunction. Furthermore, Traf3ip2 gene deletion blunts adverse remodeling 12 weeks post-I/R, as evidenced by reduced hypertrophy, fibrosis, and contractile dysfunction. Supporting the genetic approach, an interventional approach using ultrasound-targeted microbubble destruction-mediated delivery of phosphorothioated TRAF3IP2 antisense oligonucleotides into the LV in a clinically relevant time frame significantly inhibits TRAF3IP2 expression and myocardial injury in wild type mice post-I/R. Furthermore, ameliorating myocardial damage by targeting TRAF3IP2 appears to be more effective to inhibiting its downstream signaling intermediates NF-κB and JNK. Therefore, TRAF3IP2 could be a potential therapeutic target in ischemic heart disease.

  20. Novel curcumin analogue 14p protects against myocardial ischemia reperfusion injury through Nrf2-activating anti-oxidative activity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Weixin [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wu, Mingchai [Department of Pharmacy, The Third Affiliated Hospital of Wenzhou Medical University, Wenzou, Zhejiang (China); Tang, Longguang; Pan, Yong; Liu, Zhiguo [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zeng, Chunlai [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Wang, Jingying [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wei, Tiemin, E-mail: lswtm@sina.com [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Liang, Guang, E-mail: wzmcliangguang@163.com [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China)

    2015-01-15

    Background: Alleviating the oxidant stress associated with myocardial ischemia reperfusion has been demonstrated as a potential therapeutic approach to limit ischemia reperfusion (I/R)-induced cardiac damage. Curcumin, a natural compound with anti-oxidative activity, exerts beneficial effect against cardiac I/R injury, but poor chemical and metabolic stability. Previously, we have designed and synthesized a series of mono-carbonyl analogues of curcumin (MACs) with high stability. This study aims to find new anti-oxidant MACs and to demonstrate their effects and mechanisms against I/R-induced heart injury. Methods: H9c2 cells challenged with H{sub 2}O{sub 2} or TBHP were used for in vitro bio-screening and mechanistic studies. The MDA, H{sub 2}O{sub 2} and SOD levels in H9C2 cells were determined, and the cell viability was assessed by MTT assay. Myocardial I/R mouse models administrated with or without the compound were used for in vivo studies. Results: The in vitro cell-based screening showed that curcumin analogues 8d and 14p exhibited strong anti-oxidative effects. Pre-treatment of H9c2 cells with 14p activated Nrf2 signaling pathway, attenuated H{sub 2}O{sub 2}-increased MDA and SOD level, followed by the inhibition of TBHP-induced cell death and Bax/Bcl-2–caspase-3 pathway activation. Silencing Nrf2 significantly reversed the protective effects of 14p. In in vivo animal model of myocardial I/R, administration of low dose 14p (10 mg/kg) reduced infarct size and myocardial apoptosis to the same extent as the high dose curcumin (100 mg/kg). Conclusion: These data support the novel curcumin analogue 14p as a promising antioxidant to decrease oxidative stress and limit myocardial ischemia reperfusion injury via activating Nrf2. - Highlights: • Mono-carbonyl analogue of curcumin, 14p, exhibited better chemical stability. • Compound 14p inhibited TBHP-induced apoptosis through activating Nrf2 in vitro. • Compound 14p limited myocardial ischemia

  1. Influence of ulinastatin on myocardial enzyme spectrum, inflammatory state and reperfusion injury of patients with extracorporeal circulation heart operation

    Institute of Scientific and Technical Information of China (English)

    Ming-Bin Deng; Ju-Yi Wan; Yi-Bing Fang

    2016-01-01

    Objective:To study the influence of ulinastatin on the myocardial enzymes, the inflammatory state and the reperfusion injury of patients with cardiopulmonary bypass.Methods:A total of 60 patients with extracorporeal circulation heart operation in our hospital from September 2012 to August 2015 were taken as research objects. 60 patients were randomly divided into two groups: observation group (conventional surgery group with ulinastatin, 30 cases) and control group (conventional surgery group, 30 cases), and then detected and compared the related indicators of serum cardiac enzymes, inflammatory state and ischemia-reperfusion injury of two test groups at 12 h, 24 h, 72 h after operation.Results:The serum myocardial zymogram of the observation group at 12 h, 24 h and 72 h after the operation were all lower than those of the control group. Meanwhile, the inflammatory indexes and the reperfusion injury indexes of the observation group were also better than those of the control group. The test result of two groups had significant differences.Conclusions: Ulinastatin can effectively improve the myocardial enzyme spectrum and the inflammatory state of patients with extracorporeal circulation heart operation. Besides, ulinastatin is also plays active role in the prevention of reperfusion injury.

  2. Enalapril protects against myocardial ischemia/reperfusion injury in a swine model of cardiac arrest and resuscitation

    Science.gov (United States)

    Wang, Guoxing; Zhang, Qian; Yuan, Wei; Wu, Junyuan; Li, Chunsheng

    2016-01-01

    There is strong evidence to suggest that angiotensin-converting enzyme inhibitors (ACEIs) protect against local myocardial ischemia/reperfusion (I/R) injury. This study was designed to explore whether ACEIs exert cardioprotective effects in a swine model of cardiac arrest (CA) and resuscitation. Male pigs were randomly assigned to three groups: sham-operated group, saline treatment group and enalapril treatment group. Thirty minutes after drug infusion, the animals in the saline and enalapril groups were subjected to ventricular fibrillation (8 min) followed by cardiopulmonary resuscitation (up to 30 min). Cardiac function was monitored, and myocardial tissue and blood were collected for analysis. Enalapril pre-treatment did not improve cardiac function or the 6-h survival rate after CA and resuscitation; however, this intervention ameliorated myocardial ultrastructural damage, reduced the level of plasma cardiac troponin I and decreased myocardial apoptosis. Plasma angiotensin (Ang) II and Ang-(1–7) levels were enhanced in the model of CA and resuscitation. Enalapril reduced the plasma Ang II level at 4 and 6 h after the return of spontaneous circulation whereas enalapril did not affect the plasma Ang-(1–7) level. Enalapril pre-treatment decreased the myocardial mRNA and protein expression of angiotensin-converting enzyme (ACE). Enalapril treatment also reduced the myocardial ACE/ACE2 ratio, both at the mRNA and the protein level. Enalapril pre-treatment did not affect the upregulation of ACE2, Ang II type 1 receptor (AT1R) and MAS after CA and resuscitation. Taken together, these findings suggest that enalapril protects against ischemic injury through the attenuation of the ACE/Ang II/AT1R axis after CA and resuscitation in pigs. These results suggest the potential therapeutic value of ACEIs in patients with CA. PMID:27633002

  3. Mechanism of the protective effects of noninvasive limbs preconditioning on myocardial ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-guang; WU Bin-yang; WANG Jun-ke; BAI Tao

    2005-01-01

    Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning (IPC).Methods Forty Wistar rats were randomly divided into four experimental groups. In Group Ⅰ, the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group Ⅰ. In Group PL-N and Group PL-H, we administered L-nitro-arginine methyl ester (L-NAME) 10 mg/kg or hexamethonium chloride 20 mg/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was determined by triphenyltetrazolium chloride staining. Results There were no statistically significant differences in mean arterial pressure and heart rate among these groups at any time point during the experiment (P>0.05). The myocardial infarct size (IS) was decreased significantly in Group PL and Group PL-H compared with Group Ⅰ, and the IS/AAR was 34.5%±7.6%, 35.9%±8.6% and 58.5%±8.5%, respectively (P0.05).Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important role in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved.

  4. Early cardiology assessment and intervention reduces mortality following myocardial injury after non-cardiac surgery (MINS)

    Science.gov (United States)

    Hua, Alina; Pattenden, Holly; Leung, Maria; Davies, Simon; George, David A.; Raubenheimer, Hilgardt; Niwaz, Zakiyah

    2016-01-01

    Background Myocardial injury after non-cardiac surgery (MINS) is defined as troponin elevation of ≥0.03 ng/mL associated with 3.87-fold increase in early mortality. We sought to determine the impact of cardiology intervention on mortality in patients who developed MINS after general thoracic surgery. Methods A retrospective review was performed in patients over 5 years. Troponin was routinely measured and levels ≥0.04 ng/mL classified as positive. Data acquisition and mortality status was obtained via medical records and NHS tracing systems. Thirty-day mortality was compared on MINS cohort using Fisher’s exact square testing and logistic regression analysis. Results Troponin levels were measured in 491 (96%) of 511 patients. Eighty (16%) patients fulfilled the MINS criteria. Sixty-one (76%) received early cardiology consult and “myocardial infarction” stated in four (5%) patients. Risk assessment (for AMI) was undertaken; 20 (25%) patients were commenced on aspirin, four (5%) on β-blockers and one (1%) underwent percutaneous coronary intervention. Forty-nine (61%) patients received primary risk factor modifications and 26 (33%) had outpatient follow-up. There were no significant differences in the proportion of patients who died within 30 days post-operatively in the MINS group of 2.6% compared to the non-MINS group of 1.6% (P=0.625). The odds ratio for 30-day mortality in the MINS group was 1.69 (95% CI: 0.34 to 8.57, P=0.522). Conclusions MINS is common after general thoracic surgery. Early cardiology intervention reduced the expected hazard ratio of early death from 3.87 to an odds ratio of 1.69 with no significant difference in 30-day mortality for patients who developed MINS. PMID:27162667

  5. Experimental reversal of acute coronary thrombotic occlusion and myocardial injury in animals utilizing streptokinase.

    Science.gov (United States)

    Lee, G; Giddens, J; Krieg, P; Dajee, A; Suzuki, M; Kozina, J A; Ikeda, R M; DeMaria, A N; Mason, D T

    1981-12-01

    Fresh autologous thrombus, 1.0 to 1.5 ml, was injected into the left anterior descending and/or left diagonal coronary arteries of 19 open-chest dogs to produce evolving acute myocardial infarction (AMI). Thrombotic obstruction was documented by coronary angiography. Multilead epicardial ECGs showed ST segment elevations of affected left ventricular (LV) areas within 2 minutes after thrombus injection, and LV segmental wall cyanosis with hypocontraction was observed within 10 minutes in the myocardial areas supplied by the thrombosed artery. Ten animals then received an initial dose of streptokinase (STK), 250,000 U (intravenous), followed by STK, 1000 to 3000 U/min (intracoronary), while nine control dogs untreated with STK received normal saline infusion. All but one STK-treated animal (all nine animals receiving intracoronary STK) had reestablishment of blood flow in the previously occluded vessels within 1 1/2 hours, disappearance of ventricular cyanosis, return of normal LV contractile function, and normalization of elevated ST segments within 1 hour after intracoronary STK therapy. In contrast, in the non-STK-treated control group, all animals had continued coronary obstruction, progressive ST elevations, and worsening LV cyanosis and hypocontraction until death or for more than 3 hours post thrombus; three control animals died of ventricular fibrillation (VF) within 1 hour of thrombus occlusion, three more died of VF within 2 hours post thrombus, and only three survived beyond 2 hours post thrombus. Postmortem examination of non-STK-treated animals revealed extensive residual coronary thrombus. All intracoronary STK-treated animals evidenced absence of residual coronary thrombus at postmortem examination. These data provide clinically relevant evidence that early intracoronary STK effects thrombolysis in AMI by reopening coronary vessels occluded by fresh thrombus, thereby protecting myocardium from further ischemia and necrosis, preserving LV function, and

  6. Electrocardiographic alterations suggestive of myocardial injury elicited by rapid pressure lowering in hypertension.

    Science.gov (United States)

    Pepi, M; Alimento, M; Maltagliati, A; Tosi, E; Guazzi, M D

    1988-08-01

    In hypertensive cardiac hypertrophy, the elevated coronary perfusion pressure compensates importantly for the raised coronary resistance. An imbalance between perfusion and left ventricular (LV) mass, such as that occurring with rapid or excessive blood pressure lowering, may result in an inadequate oxygen supply. In 28 primary hypertensives (Group A) with LV mass index within the mean + 1 SD (96 + 19 g m-2) of 145 controls, and in 26 patients whose LV mass exceeded these values (Group B), we lowered the diastolic blood pressure rapidly to 85-90 mmHg, using both s.l. nifedipine and i.v. nitroprusside. During each test, eight patients in Group B had inversion of T waves in lead I, aVL, V3-V6, which waxed and waned in parallel with the pressure fall and recovery, and was independent of conduction disturbances, variations or group differences in the QRS axis, QTc interval, heart rate, LV fractional shortening and wall stress. A 'coronary steal phenomenon' or passive collapse in compliant lesions consequent to vasodilatation may trigger acute myocardial ischaemia in the presence of severe coronary disease. Patients developing the ECG alterations, however, were free from angina and four, who were subjected to coronary angiography, had normal arteriograms. Patients with the myocardial injury pattern showed greater LV mass indices and larger falls in diastolic pressure for it to reach normal levels. The supply of energy to the hypertrophied hypertensive heart seems to depend importantly on the coronary perfusion pressure, suggesting the cautious use of rapid acting drugs.

  7. A Role for Photobiomodulation in the Prevention of Myocardial Ischemic Reperfusion Injury: A Systematic Review and Potential Molecular Mechanisms.

    Science.gov (United States)

    Liebert, Ann; Krause, Andrew; Goonetilleke, Neil; Bicknell, Brian; Kiat, Hosen

    2017-02-09

    Myocardial ischemia reperfusion injury is a negative pathophysiological event that may result in cardiac cell apoptosis and is a result of coronary revascularization and cardiac intervention procedures. The resulting loss of cardiomyocyte cells and the formation of scar tissue, leads to impaired heart function, a major prognostic determinant of long-term cardiac outcomes. Photobiomodulation is a novel cardiac intervention that has displayed therapeutic effects in reducing myocardial ischemia reperfusion related myocardial injury in animal models. A growing body of evidence supporting the use of photobiomodulation in myocardial infarct models has implicated multiple molecular interactions. A systematic review was conducted to identify the strength of the evidence for the therapeutic effect of photobiomodulation and to summarise the current evidence as to its mechanisms. Photobiomodulation in animal models showed consistently positive effects over a range of wavelengths and application parameters, with reductions in total infarct size (up to 76%), decreases in inflammation and scarring, and increases in tissue repair. Multiple molecular pathways were identified, including modulation of inflammatory cytokines, signalling molecules, transcription factors, enzymes and antioxidants. Current evidence regarding the use of photobiomodulation in acute and planned cardiac intervention is at an early stage but is sufficient to inform on clinical trials.

  8. Telmisartan protects against microvascular dysfunction during myocardial ischemia/reperfusion injury by activation of peroxisome proliferator-activated receptor gamma

    Science.gov (United States)

    2013-01-01

    Background We investigated the potential of telmisartan to improve microvascular dysfunction induced by myocardial ischemia/reperfusion (I/R) injury by activating the peroxisome proliferator-activated receptor gamma (PPARG) pathway. Methods Forty-eight male rabbits were randomly allocated into sham-operated, I/R, GW9662, telmisartan, telmisartan–GW9662, or candesartan groups. Rabbits were anesthetized, and the left anterior descending coronary artery (LAD) was ligated for 60 minutes. Following reperfusion for 6 hours, angiotensin II content of the heart was determined using radioimmunoassay. Myocardial neutrophil accumulation and microvessel cross-sectional area were examined histologically. Myocardial capillaries were examined with transmission electron microscopy. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the myocardium were measured using enzyme-linked immunosorbent assay. Western blot was utilized for investigating the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and PPARG. Results Angiotensin II concentration was significantly increased in all treatment groups compared with the sham-operated group (P telmisartan, telmisartan-GW9662, and candesartan groups compared with the I/R group (P telmisartan group compared with the telmisartan–GW9662 and candesartan groups. Telmisartan significantly increased PPARG protein expression compared with all other groups (P telmisartan improved microvascular dysfunction during myocardial I/R injury via the PPARG pathway. PMID:23738781

  9. A Role for Photobiomodulation in the Prevention of Myocardial Ischemic Reperfusion Injury: A Systematic Review and Potential Molecular Mechanisms

    Science.gov (United States)

    Liebert, Ann; Krause, Andrew; Goonetilleke, Neil; Bicknell, Brian; Kiat, Hosen

    2017-01-01

    Myocardial ischemia reperfusion injury is a negative pathophysiological event that may result in cardiac cell apoptosis and is a result of coronary revascularization and cardiac intervention procedures. The resulting loss of cardiomyocyte cells and the formation of scar tissue, leads to impaired heart function, a major prognostic determinant of long-term cardiac outcomes. Photobiomodulation is a novel cardiac intervention that has displayed therapeutic effects in reducing myocardial ischemia reperfusion related myocardial injury in animal models. A growing body of evidence supporting the use of photobiomodulation in myocardial infarct models has implicated multiple molecular interactions. A systematic review was conducted to identify the strength of the evidence for the therapeutic effect of photobiomodulation and to summarise the current evidence as to its mechanisms. Photobiomodulation in animal models showed consistently positive effects over a range of wavelengths and application parameters, with reductions in total infarct size (up to 76%), decreases in inflammation and scarring, and increases in tissue repair. Multiple molecular pathways were identified, including modulation of inflammatory cytokines, signalling molecules, transcription factors, enzymes and antioxidants. Current evidence regarding the use of photobiomodulation in acute and planned cardiac intervention is at an early stage but is sufficient to inform on clinical trials. PMID:28181487

  10. Ginkgolide B Reduces the Degradation of Membrane Phospholipids to Prevent Ischemia/Reperfusion Myocardial Injury in Rats.

    Science.gov (United States)

    Pei, Hong-Xia; Hua, Rong; Guan, Cha-Xiang; Fang, Xiang

    2015-01-01

    Platelet-activating factor (PAF), a bioactive phospholipid, plays an important role in the integrity of the cellular membrane structure, and is involved in the pathogenesis of myocardial ischemia/reperfusion (IR) injuries. In this study, we tested the hypothesis that blockage of PAF receptor by BN 52021 (Ginkgolide B) can prevent IR-induced degradation of the myocardial membrane phospholipid, and deterioration of the cardiac function. Rat hearts in situ were subjected to 5 min ischemia and followed by 10 min reperfusion. Cardiac performances during periods of ischemia and reperfusion were monitored, and the amount of membrane phospholipids was analyzed. Myocardial total phospholipids, phosphatidylcholine, and phosphatidylethanolamine were decreased significantly in ischemia-reperfusion rat hearts compared with those of sham-operated rat hearts. Degradation of the membrane phospholipid was accompanied by the deterioration of cardiac functions and increase in serum lactate dehydrogenase (LDH) activity. BN 52021 (15 mg/kg), given by intravenous infusion 10 min prior to the left anterior descending coronary artery occlusion, reduced IR-related degradation of the myocardial phospholipids, the activity of serum LDH, and was concomitant with improvement of cardiac function. Furthermore, we demonstrated that the production of PAF was increased and BN 52021 decreased cellular damage in cultured anoxic cardiomyocytes. These results indicated that PAF antagonist BN 52021 has a protective effect against IR-induced myocardial dysfunction and degradation of the membrane phospholipids.

  11. Value of Quantitative Analysis of Serum cTnT in Diagnosis of Cardiac Disease and Myocardial Injury

    Institute of Scientific and Technical Information of China (English)

    WANG Min; LIAO Yuhua

    2000-01-01

    Serum cTnT, CK-MB and LDI were measured in 30 patients with AMI, 76 patients with VMC, 12 patients who had undergone operation without cardioplegia, 16 patients who had received open heart operation, 15 patients who had undergone thoracotomy for non-heart surgery and 55 healthy people. Concentration of serum cTnT was 0.057±0.056 μg/L in healthy people,0.069±0.032 μg/L in patients who underwent thoracotomy for non-heart surgery, 0.328±0.472μg/L in patients with VMC, 0.388±0.279 μg/L in patients with DCM, 4.259±4.619 μg/L in patients with AMI, 8.55±6.78 μg/L in patients who had undergone operation without cardioplegia and 16.03±6.01 μg/L in heart operation patients. In patients with VCM and DCM, serum cTnT was more specific and sensitive than CK-MB and LDI for diagnosing myocardial injury. In patients with AMI and heart operation patients, the increasing multiple of serum cTnT was obviously higher than that of CK-MB and LDI. 72 h after heart operation, cTnT was still higher than normal, while CK-MB had returned to normal level. Serum cTnT had higher specificity and sensitivity and longer diagnostic period in diagnosing myocardial injury. Moreover, cTnT assay could indicate the degree of myocardial injury. So, quantitative analysis of cTnT can be used as a routine examination in the diagnosis of myocardial injury.

  12. Perioperative myocardial injury after adult heart transplant: determinants and prognostic value.

    Directory of Open Access Journals (Sweden)

    Luca Salvatore De Santo

    Full Text Available Implications of Cardiac troponin (cTnI release after cardiac transplantation are still unclear. This study disclosed risk factors and prognostic implication of cTnI early levels in a single centre cohort operated on between January 1999 and December 2010.Data on 362 consecutive recipients (mean age: 47.8±13.7, 20.2% female, 18.2% diabetics, 22.1% with previous cardiac operations, 27.6% hospitalized, 84.9±29.4 ml/min preoperative glomerular filtration rate were analyzed using multivariable logistic regression modeling. Target outcomes were determinants of troponin release, early graft failure (EGF, acute kidney injury (AKI and operative death.Mean cTnI release measured 24 hours after transplant was 10.9±11.6 μg/L. Overall hospital mortality was 10.8%, EGF 10.5%, and AKI was 12.2%. cTnI release>10 μg/L proved an independent predictor of EGF (OR 2.2; 95% CI, 1.06-4.6 and AKI (OR 1.031; 95% CI, 1.001-1.064. EGF, in turn, proved a determinant of hospital mortality. Risk factors for cTnI>10 μg/L release were: status 2B (OR 0.35; 95% CI, 0.18-0.69, protective, duration of the ischemic period (OR 1.006; 95% CI, 1.001-1.011, previous cardiac operation (OR 2.9; 95% CI, 1.67-5.0, and left ventricular hypertrophy (OR 3.3; 95% CI, 1.9-5.6.Myocardial enzyme leakage clearly emerged as an epiphenomenon of more complicated clinical course. The complex interplay between surgical procedure features, graft characteristics and recipient end-organ function highlights cTnI release as a risk marker of graft failure and acute kidney injury. The search for optimal myocardial preservation is still an issue.

  13. Nanoparticle-Mediated Delivery of Irbesartan Induces Cardioprotection from Myocardial Ischemia-Reperfusion Injury by Antagonizing Monocyte-Mediated Inflammation

    Science.gov (United States)

    Nakano, Yasuhiro; Matoba, Tetsuya; Tokutome, Masaki; Funamoto, Daiki; Katsuki, Shunsuke; Ikeda, Gentaro; Nagaoka, Kazuhiro; Ishikita, Ayako; Nakano, Kaku; Koga, Jun-Ichiro; Sunagawa, Kenji; Egashira, Kensuke

    2016-07-01

    Myocardial ischemia-reperfusion (IR) injury limits the therapeutic effect of early reperfusion therapy for acute myocardial infarction (AMI), in which the recruitment of inflammatory monocytes plays a causative role. Here we develop bioabsorbable poly-lactic/glycolic acid (PLGA) nanoparticles incorporating irbesartan, an angiotensin II type 1 receptor blocker with a peroxisome proliferator-activated receptor (PPAR)γ agonistic effect (irbesartan-NP). In a mouse model of IR injury, intravenous PLGA nanoparticles distribute to the IR myocardium and monocytes in the blood and in the IR heart. Single intravenous treatment at the time of reperfusion with irbesartan-NP (3.0 mg kg‑1 irbesartan), but not with control nanoparticles or irbesartan solution (3.0 mg kg‑1), inhibits the recruitment of inflammatory monocytes to the IR heart, and reduces the infarct size via PPARγ-dependent anti-inflammatory mechanisms, and ameliorates left ventricular remodeling 21 days after IR. Irbesartan-NP is a novel approach to treat myocardial IR injury in patients with AMI.

  14. IL-23 Promotes Myocardial I/R Injury by Increasing the Inflammatory Responses and Oxidative Stress Reactions

    Directory of Open Access Journals (Sweden)

    Xiaorong Hu

    2016-05-01

    Full Text Available Background/Aims: Inflammation and oxidative stress play an important role in myocardial ischemia and reperfusion (I/R injury. We hypothesized that IL-23, a pro-inflammatory cytokine, could promote myocardial I/R injury by increasing the inflammatory response and oxidative stress. Methods: Male Sprague-Dawley rats were randomly assigned into sham operated control (SO group, ischemia and reperfusion (I/R group, (IL-23 + I/R group and (anti-IL-23 + I/R group. At 4 h after reperfusion, the serum concentration of lactate dehydrogenase (LDH, creatine kinase (CK and the tissue MDA concentration and SOD activity were measured. The infarcte size was measured by TTC staining. Apoptosis in heart sections were measured by TUNEL staining. The expression of HMGB1 and IL-17A were detected by Western Blotting and the expression of TNF-α and IL-6 were detected by Elisa. Results: After 4 h reperfusion, compared with the I/R group, IL-23 significantly increased the infarct size, the apoptosis of cardiomyocytes and the levels of LDH and CK (all P 0.05. All these effects were abolished by anti-IL-23 administration. Conclusion: The present study suggested that IL-23 may promote myocardial I/R injury by increasing the inflammatory responses and oxidative stress reaction.

  15. Cardioprotective effects of Guanxinshutong (GXST) against myocardial ischemia/reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Zhuo Liang; Li-Feng Liu; Tian-Ming Yao; Yu Huo; Ya-Ling Han

    2012-01-01

    Background The protective effects against reperfusion injury of cardioprotective drugs have recently been evaluated and found to be inadequate. Guanxinshutong (GXST), a combination of the traditional herb and Mongolian medicine, is effective and safe in treating angina pectoris in clinical trials. We assess the cardioprotective effects of GXST against myocardial ischemia and reperfusion (MI/R) injury in rats and explore its possible mechanism. Methods Forty-five male Sprague Dawley rats were randomized into three groups: non-MI/R group (Sham, n = 15), MI/R group treated with vehicle (Control, n = 15) and MI/R group treated with GXST (Drug, n = 15). MI/R was induced by ligation of the left anterior descending coronary artery (LAD) for 30 minutes, followed by 2/24 hour reperfusion in the Control and Drug groups. In the Sham group, the LAD was exposed without occlusion. GXST powder (in the Drug group) or saline (in the Control and Sham groups) were administered via direct gastric gavage from 7 day prior to surgery. Blood samples were collected from the carotid artery (10 rats each group) after 2 hours of reperfusion, to determine the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1) using enzyme-linked immunosorbent assays. The animals were then sacrificed and the hearts were harvested for histopathology and western blot analysis. Infarct size was measured in the remaining five rats in each group after 24 hours reperfusion. Results GXST significantly decreased levels of TNF-α, IL-1β, IL-6, ICAM-1, apoptosis index (AI) and infarct size. GXST also obviously inhibited nuclear factor kappa B (NF-κB) activity when compared with the Control group (all P < 0.05). Conclusions GXST is effective in protecting the myocardium against MI/R injury in rats. Its possible cardioprotective mechanism involves inhibition of the inflammatory response and apoptosis following MI/R injury.

  16. Heparins with reduced anti-coagulant activity reduce myocardial reperfusion injury.

    Science.gov (United States)

    Barry, William H; Kennedy, Thomas P

    2011-05-01

    Heparin which is desulfated at the 2-O and 3-O positions (ODSH) has reduced anti-coagulant properties, and reduced interaction with heparin antibodies. Because of the reduced anti-coagulant effect, ODSH can be safely administered to animals and humans intravenously at doses up to 20 mg/kg, resulting in a serum concentration of up to 250µg/ml. Administration of ODSH causes a 35% reduction in infarct size in dogs and pigs subjected to coronary artery occlusion and reperfusion when given 5 min before reperfusion. ODSH has anti-inflamatory effects, manifest as a decrease in neutrophil infiltration into ischemic tissue at high doses, but this effect does not entirely account for the reduction in infarct size. ODSH decreases Na(+) and Ca(2+) loading in isolated cardiac myocytes subjected to simulated ischemia. This effect appears due to an ODSH-induced reduction in an enhanced Na(+) influx via the Na channel in the membrane of cardiac myocyes caused by oxygen radicals generated during ischemia and reperfusion. Reduction in Na(+) influx decreases Ca(2+) loading by reducing Ca2(+) influx via Na/Ca exchange, thus reducing Ca(2+) - dependent reperfusion injury. ODSH does not appear to interact with antibodies to the heparin/platelet factor 4 complex, and does not cause heparin-induced thrombocytopenia. Because of these therapeutic and safety considerations, ODSH would appear to be a promising heparin derivative for prevention of reperfusion injury in humans undergoing thrombolytic or catheter-based reperfusion for acute myocardial infarction. The review article discussed the use of heparin and the discussion of some of the important patents, including: US6489311; US7478358; PCTUS2008070836 and PCTUS2009037836.

  17. Effects of phytoestrogen genistein on myocardial ischemia/reperfusion injury and apoptosis in rabbits

    Institute of Scientific and Technical Information of China (English)

    En-sheng JI; Hua YUE; Yu-ming WU; Rui-rong HE

    2004-01-01

    AIM: To study the effect of genistein (GST) on rabbit heart ischemia/reperfusion (I/R) injury. METHODS: Rabbit heart I/R injury was induced by occluding the left anterior descending coronary artery for 45 min and reperfusing for 180 min. GST (1.0 mg/kg) was intravenously injected 5 min before heart ischemia. Hemodynamic data, infarct size, and cardiomyocytic apoptosis were measured. The pathologic changes of I/R myocardium were observed.RESULTS: During the I/R, heart rate, mean arterial blood pressure, myocardial oxygen consumption, left ventricular (LV) -dp/dtmax and +dp/dtmax were decreased progressively. The infarct size was occupied 60.23 %±3.97 % (%of area at risk) in vehicle +I/R group while GST reduced the infarct size to 39.62 %±4.30 % (P<0.01). DNA ladder patter in myocardium was revealed by agarose gel electrophoresis in vehicle +I/R group while was not found in GST+I/R group. Apoptotic cardiomyocytes were sparse within ischemic myocardium at risk in GST+I/R group as compared with that in vehicle +I/R group (TUNEL stain). Apoptosis rate in ischemic myocardium from vehicle +I/R and GST+I/R groups detected by flow cytometry were 15.33 %±1.31% and 3.88 %±0.33 %,respectively. Fas and Bax protein expressions in ischemic myocardium of vehicle +I/R group were higher than that in GST+I/R group (P<0.01). Bcl-2/Bax ratio in vehicle +I/R group was lower than that in nonischemic myocardium (P<0.01), while in GST+I/R group, the Bcl-2/Bax ratio was higher than that in vehicle +I/R group (P<0.01).CONCLUSION: GST reduced infarct size and apoptosis of myocytes in I/R rabbit heart.

  18. Activation of SHH signaling pathway promotes vasculogenesis in post-myocardial ischemic-reperfusion injury.

    Science.gov (United States)

    Guo, Wei; Yi, Xin; Ren, Faxin; Liu, Liwen; Wu, Suning; Yang, Jun

    2015-01-01

    This study aimed to investigate the potential roles of sonic Hedgehog (SHH) expression in vasculogenesis in post-myocardial ischemic-reperfusion injury (MIRI) and its underlying mechanism. Cardiac microvascular endothelial cells (CMECs) isolated from the SD rat hearts tissues were used to construct the MIRI model. mRNA level of SHH in control cells and MIRI cells was detected using RT-PCR analysis. Furthermore, effects of SHH expression on CMECs viability and apoptosis were analyzed using MTT assay and Annexin-V-FITC kit respectively. Moreover, effects of SHH expression on the pathway signal proteins expression was analyzed using ELISA and western blotting. mRNA level of SHH was significantly decreased compared to the controls (PSHH application compared with the controls (PSHH application, as well as the SHH signal proteins including Patch-1, Gli1, Gli2 and SMO (PSHH application on biological factors levels were reversed by the SHH inhibitor application. This study suggested that SHH over expression may play a pivotal contribute role in vasculogenesis through activating the SHH signals in post-MIRI.

  19. Role of Sida cordifolia L. leaves on biochemical and antioxidant profile during myocardial injury.

    Science.gov (United States)

    Kubavat, J B; Asdaq, S M B

    2009-07-06

    The Sida cordifolia L. (Family: Malvaceae) is a widely allocated herb by folk tribes of Gujarat state of India for the treatment of coronary manifestations. However, no published data relevant to use of the plant is available. The aim of the present study was to evaluate the antioxidant and biochemical profile of hydroalcoholic extract of Sida cordifolia L. (HESC) leaves against myocardial infarction (MI) in rats. Albino rats were administered HESC (100 and 500 mg/kg) and propranolol (10 mg/kg) once daily orally for 30 days. At the end of treatment period, MI was induced by administering isoproterenol (ISO) or by subjecting heart to ischemia reperfusion injury (IRI). Endogenous biomarkers (LDH and CK-MB) and antioxidants (SOD and catalase) were estimated in serum/perfusate and heart tissue homogenate (HTH). The LDH and CK-MB activities were elevated in HTH and depleted in serum/perfusate of HESC and propranolol groups when compared to ISO/IRI control. Further, it was found that both doses significantly increased endogenous antioxidants in HTH. Moreover, biochemical findings were supported by histopathological observations. The result confirm, at least in part, for the use of Sida cordifolia in folk medicine to treat MI.

  20. Detection of (reversible) myocardial ischemic injury by means of electrical bioimpedance.

    Science.gov (United States)

    Mellert, Fritz; Winkler, Kai; Schneider, Christian; Dudykevych, Taras; Welz, Armin; Osypka, Markus; Gersing, Eberhard; Preusse, Claus J

    2011-06-01

    The scope of this paper was to determine whether ischemic and reperfusion damage in cardiac surgery can be detected by measurement of electrical bioimpedance (EBI). Conventional pacing wires were replaced by pacing wires with sputtered iridium coating in order to reduce polarization associated with two-electrode impedance measurements. A custom-built bioimpedance analyzer (Osypka Medical GmbH, Berlin, Germany) measured the real part of impedance Re(Z) and the phase (ϕ) at three frequencies (1, 10, and 1000 kHz) and determined an extracellular space index (EZRI) as the quotient of Re(Z) at 1000 kHz and Re(Z) at 1 kHz. Our study included six patients (conventional coronary artery bypass graft, age 68.1 ± 8.3 years) subject to routine cardioplegic ischemia and reperfusion. Preischemic bioimpedance measurements were not impaired by interference of the beating heart. Intraischemically, bioimpedance at 1 kHz and phase at 10 kHz increased until opening of a bypass graft, which is probably induced by closure of gap junctions and cell swelling processes. After cross clamping, EZRI slowly decreased as an effect of mild cell swelling. After ischemia, values returned almost to baseline measurements, indicating sufficient reperfusion processes. Measurement of EBI correlates with myocardial ischemic injury and is applicable in a two-electrode setup providing low-polarization pacing wires.

  1. Pharmacological Postconditioning with Lactic Acid and Hydrogen Rich Saline Alleviates Myocardial Reperfusion Injury in Rats

    Science.gov (United States)

    Zhang, Guoming; Gao, Song; Li, Xiaoyan; Zhang, Lulu; Tan, Hong; Xu, Lin; Chen, Yaoyu; Geng, Yongjian; Lin, Yanliang; Aertker, Benjamin; Sun, Yuanyuan

    2015-01-01

    This study investigated whether pharmacological postconditioning with lactic acid and hydrogen rich saline can provide benefits similar to that of mechanical postconditioning. To our knowledge, this is the first therapeutic study to investigate the co-administration of lactic acid and hydrogen. SD rats were randomly divided into 6 groups: Sham, R/I, M-Post, Lac, Hyd, and Lac + Hyd. The left coronary artery was occluded for 45 min. Blood was withdrawn from the right atrium to measure pH. The rats were sacrificed at different time points to measure mitochondrial absorbance, infarct size, serum markers and apoptotic index. Rats in Lac + Hyd group had similar blood pH and ROS levels when compared to the M-Post group. Additionally, the infarct area was reduced to the same extent in Lac + Hyd and M-Post groups with a similar trends observed for serum markers of myocardial injury and apoptotic index. Although the level of P-ERK in Lac + Hyd group was lower, P-p38/JNK, TNFα, Caspase-8, mitochondrial absorbance and Cyt-c were all similar in Lac + Hyd and M-Post groups. The Lac and Hyd groups were able to partially mimic this protective role. These data suggested that pharmacological postconditioning with lactic acid and hydrogen rich saline nearly replicates the benefits of mechanical postconditioning. PMID:25928542

  2. Salidroside attenuates myocardial ischemia-reperfusion injury via PI3K/Akt signaling pathway.

    Science.gov (United States)

    Xu, Mao-Chun; Shi, Hai-Ming; Gao, Xiu-Fang; Wang, Hao

    2013-01-01

    To investigate the cardioprotective effects of salidroside on myocardial ischemia-reperfusion injury (IRI) in rabbits and the underlying action mechanisms in PI3K/Akt signaling pathway, a rabbit ischemia/reperfusion model was created by ligating the left anterior descending coronary arterial branch for 30 min and by releasing the ligature to allow reperfusion for 120 min. Salidroside or salidroside+PI3K inhibitor (LY294002) was administered via intracoronary injections at the onset of reperfusion. Apoptosis of cardiomyocytes was assessed by terminal dUTP nick-end labeling assay, and the expression of apoptosis-related proteins was observed by immunohistochemistry. The expressions of total Akt and phosphorylated Akt (p-Akt) were detected by western blot analysis. The results showed that intracoronary injection of salidroside at the onset of reperfusion markedly reduced the apoptosis of cardiomyocytes, significantly increasing Bcl-2 and p-Akt proteins expressions and decreasing Bax and caspase-3 expressions in the hearts subjected to ischemia followed by 120-min reperfusion. However, the anti-apoptotic effect induced by salidroside was inhibited by LY294002, which blocked the activation of Akt. These results suggested that intracoronary administration of salidroside at the onset of reperfusion could significantly reduce the IRI-induced apoptosis of cardiomyocytes, and this protective mechanism seemed to be mediated by the PI3K-Akt signaling pathway.

  3. Quercetin protects against heat stroke-induced myocardial injury in male rats: Antioxidative and antiinflammatory mechanisms.

    Science.gov (United States)

    Lin, Xiaojing; Lin, Cheng-Hsien; Zhao, Tingbao; Zuo, Dan; Ye, Zhujun; Liu, Lin; Lin, Mao-Tsun

    2017-03-01

    Heat stroke is characterized by hyperthermia, systemic inflammation, and multiple organ failure including arterial hypotension. This definition can be fulfilled by a rat model of heat stroke used in the present study. Anesthetized animals were exposed to heat exposure (43 °C for 70 min) and then returned to room temperature (26 °C) for recovery. One hour before heat exposure, an intraperitoneal dose of quercetin (30 mg/kg) or vehicle (normal saline 1 ml/kg) was administered to the experimental groups of rats. Additional injection was administered immediately after the onset of heat stroke. Immediately after the onset of heat stroke. Vehicle-treated rats displayed (i) hyperthermia; (ii) suppressed left ventricular function; (iii) decreased contents of cardiac total antioxiant capacity (e.g., superoxide dismutase, glutathione peroxidase, catalase); (iv) increased contents of cardiac oxidative capacity malondialdehyde and thiobarbituric acid reactive substances; (v) increased cardiac levels of pro-inflammatory cytokines tumor necrosis factor-α and interleukin-6; and (vi) decreased cardiac levels of an anti-inflammatory cytokine interleukin 10. Histopathologic and survival observation provided supportive evidence for biochemical analyses. These heat stroke reactions all can be significantly attenuated by quercetin therapy. Our data suggest that quercetin therapy might improve outcomes of heat stroke in rats by attenuating excessive hyperthermia as well as myocardial injury. The protective effects of quercetin could be attributed to anti-lipid peroxidative, anti-oxidant, and anti-inflammatory properties.

  4. Orientin protects myocardial cells against hypoxia-reoxygenation injury through induction of autophagy.

    Science.gov (United States)

    Liu, Liya; Wu, Youxi; Huang, Xiulan

    2016-04-05

    Orientin, a flavonoid exists in Chinese traditional herbal Polygonum orientale L., has been previously demonstrated to protect against myocardial ischemia reperfusion injury (MIRI) through inhibition of apoptosis. However, the underlying mechanisms remain to be elucidated and we therefore in this study investigated the effects of orientin on autophagy during MIRI in rats. The results indicate that orientin, at the concentrations of 10 and 30 μM in the cultures of neonatal rat cardiomyocytes, promoted the induction of autophagy, increasing the formation of autophagosomes and enhancing the expression of LC3 puncta, LC3-II/LC3-I ratio and Beclin 1 after hypoxia/reoxygenation. The induction of autophagy by orientin correlated with enhanced cell viability and decreased apoptosis, which was significantly attenuated by autophagy inhibitor wortmannin, a phosphatidylinositol-3-kinase (PI3K) inhibitor. Moreover, application of orientin increased the activation of AMPK and Akt, downregulated the phosphorylation of mammalian target of rapamycin (mTOR) and the expression of Raptor, and enhanced the interaction between Beclin 1 and Bcl-2 in endoplasmic reticulum due to increased phosphorylation of Beclin 1 and decreased phosphorylation of Bcl-2. Our investigation suggests that the cardioprotective effects of orientin during MIRI may be mediated through the balance of autophagy through regulating AMPK, Akt, mTOR, and Bcl-2 associated signaling pathways. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Non-cardiogenic pulmonary edema, rhabdomyolysis and myocardial injury following heroin inhalation: a case report

    Science.gov (United States)

    Bazoukis, G; Spiliopoulou, A; Mourouzis, K; Grigoropoulou, P; Yalouris, A

    2016-01-01

    Background: Heroin use by non-injecting routes of administration (snorting, swallowing, “chasing the dragon”) is considered to be safer but is not risk-free for fatal overdose or serious side effects. We report the case of an adolescent who was transferred unconscious to the emergency department after heroin inhalation. Description of the case: A 17-year-old male was transferred to the emergency department unconscious (Glasgow coma scale: 6/15) after heroin inhalation. He was treated with non-rebreather mask and intravenous infusion of naloxone with gradual improvement of consciousness and arterial blood gasses. The chest computed tomography showed signs of acute respiratory distress syndrome. Laboratory exams on the second day of hospitalization showed elevated creatine kinase (CK) and troponin-I levels while his electrocardiography (ECG) showed J-point elevation in V1, V2, and V3 precordial leads. On the second day of hospitalization the pulmonary infiltrates were not present in his chest X-ray while on the eighth day, troponin-I and CK levels were normalized without dynamic ECG changes and the patient was discharged uneventfully. Conclusion: Heroin inhalation may cause severe complications, such as non-cardiogenic pulmonary edema, rhabdomyolysis or myocardial injury. Hippokratia 2016, 20(1): 84-87 PMID:27895451

  6. Hydrosulfide attenuates acute myocardial ischemic injury through the glycogen synthase kinase-3β/β-catenin signaling pathway.

    Science.gov (United States)

    Ge, Ning; Liu, Chao; Li, Guofeng; Xie, Lijun; Zhang, Qinzeng; Li, Liping; Hao, Na; Zhang, Jianxin

    2016-05-01

    The endogenous signaling gasotransmitter, hydrosulfide (H2S), has been shown to exert cardioprotective effects against acute myocardial infarction (AMI) due to ischemic injury. However, the mechanisms responsible for these effects are not yet fully understood. In this study, we investigated whether sodium hydrogen sulfide (NaHS), an H2S donor, attenuates acute myocardial ischemic injury through glycogen synthase kinase-3β (GSK-3β)/β-catenin signaling. For this purpose, we utilized an in vivo rat model of AMI by occluding the left anterior descending coronary artery. NaHS (0.39, 0.78 or 1.56 mg/kg, intraperitoneally), the GSK-3β inhibitor, SB216763 (0.6 mg/kg, intravenously), or 1% dimethylsulfoxide (2 ml/kg, intravenously) were administered to the rats. The results demonstrated that the administration of medium- and high-dose NaHS and SB216763 significantly improved rat cardiac function, as evidenced by an increase in the mean arterial pressure, left ventricular developed pressure, contraction and relaxation rates, as well as a decrease in left ventricular end-diastolic pressure. In addition, the administration of NaHS and SB216763 attenuated myocardial injury as reflected by a decrease in apoptotic cell death and in the serum lactate dehydrogenase concentrations, and prevented myocardial structural changes. The administration of NaHS and SB216763 increased the concentrations of phosphorylated (p-)GSK-3β, the p-GSK-3β/t-GSK-3β ratio and downstream protein β-catenin. Moreover, western blot and immunohistochemical analyses of apoptotic signaling pathway proteins further established the cardioprotective potential of NaHS, as reflected by the upregulation of Bcl-2 expression, the downregulation of Bax expression, and a decrease in the number of TUNEL-positive stained cells. These findings suggest that hydrosulfide exerts cardioprotective effects against AMI-induced apoptosis through the GSK-3β/β-catenin signaling pathway.

  7. Activation of ALDH2 with Low Concentration of Ethanol Attenuates Myocardial Ischemia/Reperfusion Injury in Diabetes Rat Model

    Directory of Open Access Journals (Sweden)

    Pin-Fang Kang

    2016-01-01

    Full Text Available The aim of this paper is to observe the change of mitochondrial aldehyde dehydrogenase 2 (ALDH2 when diabetes mellitus (DM rat heart was subjected to ischemia/reperfusion (I/R intervention and analyze its underlying mechanisms. DM rat hearts were subjected to 30 min regional ischemia and 120 min reperfusion in vitro and pretreated with ALDH2 activator ethanol (EtOH; cardiomyocyte in high glucose (HG condition was pretreated with ALDH2 activator Alda-1. In control I/R group, myocardial tissue structure collapse appeared. Compared with control I/R group, left ventricular parameters, SOD activity, the level of Bcl-2/Bax mRNA, ALDH2 mRNA, and protein expressions were decreased and LDH and MDA contents were increased, meanwhile the aggravation of myocardial structure injury in DM I/R group. When DM I/R rats were pretreated with EtOH, left ventricular parameters, SOD, Bcl-2/Bax, and ALDH2 expression were increased; LDH, MDA, and myocardial structure injury were attenuated. Compared with DM + EtOH I/R group, cyanamide (ALDH2 nonspecific blocker, atractyloside (mitoPTP opener, and wortmannin (PI3K inhibitor groups all decreased left ventricular parameters, SOD, Bcl-2/Bax, and ALDH2 and increased LDH, MDA, and myocardial injury. When cardiomyocyte was under HG condition, CCK-8 activity and ALDH2 protein expression were decreased. Alda-1 increased CCK-8 and ALDH2. Our findings suggested enhanced ALDH2 expression in diabetic I/R rats played the cardioprotective role, maybe through activating PI3K and inhibiting mitoPTP opening.

  8. Protective effects of pinacidil hyperpolarizing cardioplegia on myocardial ischemia reperfusion injury by mitochondrial KATP channels

    Institute of Scientific and Technical Information of China (English)

    YU Tian; FU Xiao-yun; LIU Xing-kui; YU Zhi-hao

    2011-01-01

    Background Many studies have indicated that hyperpolarizing cardioplegia is responsible for myocardial preservation and researchers have suggested that the adenosine triphosphate-sensitive potassium channels (KATP) were the end effectors of cardio-protection.But whether mitochondrial KATP plays an important role in hyperpolarizing cardioplegia is not apparent.The present study investigated the effect of hyperpolarizing cardioplegia containing pinacidil (a nonselective KATP opener) on ischemia/reperfusion injury in rat hearts,especially the role of mitochondrial KATP in pinacidil hyperpolarizing cardioplegia.Methods Sprague-Dawley rat hearts were Langendorff-perfused for 20 minutes with Krebs-Henseleit buffer at 37℃before equilibration.Cardiac arrest was then induced in different treatments:there was no arrest and ischemia in the normal group,the control group were arrested by clamping the aorta,depolarizing caidioplegia (St.Thomas solution containing 16 mmol/L KCI) and hyperpolarizing cardioplegia groups used St.Thomas solution containing 0.05 mmol/L pinacidil and 5 mmol/L KCI to induce cardiac arrest in group hyperkalemic and group pinacidil,in group hyperkalemic + 5-hydroxydecanote (5HD) and Pinacidil + 5HD,5HD (0.1 mmol/L) was added to the above two solutions to block mitochondria KATP channels.Global ischemia was then administrated for 40 minutes at 37℃,followed by 30 minutes of reperfusion.At the end of equilibration and reperfusion,hemodynamics,ultrastructure,and mitochondrial function were measured.Results In the control group,ischemia/reperfusion decreased the left ventricular developed pressure,heart rate,coronary flow,mitochondrial membrane potential,impaired mitochondrial respiratory function,increased reactive oxygen species and left ventricular end diastolic pressure.Damage to myocardial ultrastructure was also evident.Both depolarized arrest and especially hyperpolarized cardioplegia significantly reduced these lesions.5HD partially blocked the

  9. Inhibition of ALDH2 by O-GlcNAcylation contributes to the hyperglycemic exacerbation of myocardial ischemia/reperfusion injury.

    Science.gov (United States)

    Liu, Baoshan; Wang, Jiali; Li, Minghua; Yuan, Qiuhuan; Xue, Mengyang; Xu, Feng; Chen, Yuguo

    2016-12-27

    Although hyperglycemia is causally related to adverse outcomes after myocardial ischemia/reperfusion (I/R), the underlying mechanisms are largely unknown. Here, we investigated whether excessive O-linked-N-acetylglucosamine (O-GlcNAc) modification of acetaldehyde dehydrogenase 2 (ALDH2), an important cardioprotective enzyme, was a mechanism for the hyperglycemic exacerbation of myocardial I/R injury. Both acute hyperglycemia (AHG) and diabetes (DM)-induced chronic hyperglycemia increased cardiac dysfunction, infarct size and apoptosis index compared with normal saline (NS)+I/R rats (PO-GlcNAc modification was increased whereas its activity was decreased in AHG+I/R and DM+I/R rats. High glucose (HG, 30mmol/L) markedly increased ALDH2 O-GlcNAc modification compared with Con group (5mmol/L) (PO-GlcNAc modification was increased by 62.9% in Con+PUGNAc group whereas it was decreased by 44.1% in Con+DON group compared with Con group (PO-GlcNAc modification and improved infarct size, apoptosis index and cardiac dysfunction induced by I/R combined with hyperglycemia. These findings demonstrate that ALDH2 O-GlcNAc modification is a key mechanism for the hyperglycemic exacerbation of myocardial I/R injury and Alda-1 has therapeutic potential for inducing cardioprotection.

  10. Achyranthes bidentata Polypeptides Reduces Oxidative Stress and Exerts Protective Effects against Myocardial Ischemic/Reperfusion Injury in Rats

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    Haifeng Zhang

    2013-09-01

    Full Text Available Achyranthes bidentata, a Chinese medicinal herb, is reported to be neuroprotective. However, its role in cardioprotection remains largely unknown. Our present study aimed to investigate the effects of Achyranthes bidentata polypeptides (ABPP preconditioning on myocardial ischemia/reperfusion (MI/R injury and to test the possible mechanisms. Rats were treated with ABPP (10 mg/kg/d, i.p. or saline once daily for one week. Afterward, all the animals were subjected to 30 min of myocardial ischemia followed by 4 h of reperfusion. ABPP preconditioning for one week significantly improved cardiac function following MI/R. Meanwhile, ABPP reduced infarct size, plasma creatine kinase (CK/lactate dehydrogenase (LDH activities and myocardial apoptosis at the end of reperfusion in rat hearts. Moreover, ABPP preconditioning significantly inhibited superoxide generation, gp91phox expression, malonaldialdehyde formation and enhanced superoxide dismutase activity in I/R hearts. Furthermore, ABPP treatment inhibited PTEN expression and increased Akt phosphorylation in I/R rat heart. PI3K inhibitor wortmannin blocked Akt activation, and abolished ABPP-stimulated anti-oxidant effect and cardioprotection. Our study demonstrated for the first time that ABPP reduces oxidative stress and exerts cardioprotection against MI/R injury in rats. Inhibition of PTEN and activation of Akt may contribute to the anti-oxidant capacity and cardioprotection of ABPP.

  11. Pharmacokinetics of ligustrazine ethosome patch in rats and anti-myocardial ischemia and anti-ischemic reperfusion injury effect

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    Liu X

    2011-07-01

    Full Text Available Xingyan Liu1, Hong Liu1, Zhaowu Zeng2, Weihua Zhou3, Jianqiang Liu2, Zhiwei He11China-America Cancer Research Institute, Guangdong Medical College, 2Guangdong Key Laboratory for Research and Development of Natural Drugs, Guangdong Medical College, Dongguan, Guangdong, 3Yichun University, Yichun, Jiangxi, People's Republic of ChinaAbstract: The objective of this study was to investigate the pharmacokinetics of the ligustrazine ethosome patch and antimyocardial ischemia and anti-ischemic reperfusion injury effect. Male Sprague Dawley rats were divided randomly into 3 groups: Group A (intragastric ligustrazine, Group B (transdermal ligustrazine ethosome patch, and Group C (conventional transdermal ligustrazine patch. After treatment, samples of blood and of various tissues such as heart, liver, spleen, lung, kidney, brain, and muscle samples were taken at different time points. Drug concentration was measured with HPLC, and the drug concentration–time curve was plotted. Pharmacokinetic software 3p97 was applied to calculate pharmacokinetic parameters and the area under the drug concentration–time curve (AUC in various tissues. The rat model of acute myocardial ischemia was constructed with intravenous injection of pituitrin and the model of myocardial ischemia-perfusion injury was constructed by tying off the left anterior descending coronary artery of rats to observe the effect of ligustrazine ethosome patches on ischemic myocardium and ischemia-reperfusion injury. Results showed that AUC was highest in the transdermal drug delivery group of ligustrazine ethosome patch. There were significant differences in whole blood viscosity, plasma viscosity, hematocrit, red blood cell aggregation index, and deformation index between ligustrazine the ethosome patch group and ischemic control group (P < 0.01. Moreover, ligustrazine ethosome patches could reduce the scope of myocardial infarction induced by long-term ischemia. Ligustrazine ethosome patches

  12. MCT1 and MCT4 Expression During Myocardial Ischemic-Reperfusion Injury in the Isolated Rat Heart

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    Yi Zhu

    2013-09-01

    Full Text Available Background/Aims: Myocardium ischemia-reperfusion (I/R injury can be caused by imbalances in cellular metabolism. Lactate, transported by monocarboxylate transporters (MCTs, has been implicated as a mechanism in this process. The present study was designed to investigate the expression and functional role of MCTs in rat hearts during ischemia and reperfusion. Methods: Langendorff-perfused rat hearts were subjected to 20 minutes stabilization, 30 minutes of global ischemia and 60 minutes reperfusion. Hearts were collected serially for detecting expression changes in MCT1, MCT4 during myocardial I/R injury and lactate concentration was measured. Post-ischemic left ventricular function and infract size were determined at end-point, followed by the pretreatment of D-lactate, a competitive inhibitor of MCTs. Results: MCT4 was significantly increased following global ischemia and MCT1 expression was increased during the early stages of reperfusion in isolated rat hearts, while the expression of the ancillary protein CD147 was increased during I/R injury. We determined increases in AMPK phosphorylation status, which was significantly elevated following ischemia and early reperfusion. Blocking monocarboxylate transport by competitive inhibition with D-lactate caused decreased left ventricular performance and increased infarct size. Conclusion: Increased MCT4 expression facilitates lactate extrusion during the ischemic period, while increased MCT1 may facilitate lactate transport into and out of cells simultaneously during early reperfusion, with increases in AMPK phosphorylation status during the myocardial I/R period. Lactate transport by MCTs has a profound protective effect during myocardial ischemia reperfusion injury.

  13. Doxorubicin induced myocardial injury is exacerbated following ischaemic stress via opening of the mitochondrial permeability transition pore

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    Gharanei, M.; Hussain, A. [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom); Janneh, O. [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom); Pharmacology Research Laboratories, 70, Pembroke Place, The University of Liverpool, Liverpool. L69 3GF (United Kingdom); Maddock, H.L., E-mail: h.maddock@coventry.ac.uk [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom)

    2013-04-15

    Chemotherapeutic agents such as doxorubicin are known to cause or exacerbate cardiovascular cell death when an underlying heart condition is present. However, the mechanism of doxorubicin-induced cardiotoxicity is unclear. Here we assess the cardiotoxic effects of doxorubicin in conditions of myocardial ischaemia reperfusion and the mechanistic basis of protection, in particular the role of the mitochondrial permeability transition pore (mPTP) in such protection. The effects of doxorubicin (1 μM) ± cyclosporine A (CsA, 0.2 μM; inhibits mPTP) were investigated in isolated male Sprague–Dawley rats using Langendorff heart and papillary muscle contraction models subjected to simulated ischaemia and reperfusion injury. Isolated rat cardiac myocytes were used in an oxidative stress model to study the effects of drug treatment on mPTP by confocal microscopy. Western blot analysis evaluated the effects of drug treatment on p-Akt and p-Erk 1/2 levels. Langendorff and the isometric contraction models showed a detrimental effect of doxorubicin throughout reperfusion/reoxygenation as well as increased p-Akt and p-Erk levels. Interestingly, CsA not only reversed the detrimental effects of doxorubicin, but also reduced p-Akt and p-Erk levels. In the sustained oxidative stress assay to study mPTP opening, doxorubicin decreased the time taken to depolarization and hypercontracture, but these effects were delayed in the presence of CsA. Collectively, our data suggest for the first that doxorubicin exacerbates myocardial injury in an ischaemia reperfusion model. If the inhibition of mPTP ameliorates the cardiotoxic effects of doxorubicin, then more selective inhibitors of mPTP should be further investigated for their utility in patients receiving doxorubicin. - Highlights: ► Doxorubicin exacerbates myocardial ischaemia reperfusion injury. ► Co-treatment with CsA protects against doxorubicin induced myocardial injury. ► CsA delays doxorubicin induced mPTP opening in laser

  14. Remote postconditioning induced by brief pulmonary ischemia and reperfusion attenuates myocardial reperfusion injury in rabbits

    Institute of Scientific and Technical Information of China (English)

    TANG Yan-hua; XU Jian-jun; LI Ju-xiang; CHENG Xiao-shu

    2011-01-01

    Background The lung is one of the most important organs that are sensitive to ischemia. We hypothesized that remote postconditioning (RPostC) induced by brief occlusion and reperfusion of the pulmonary artery could attenuate myocardial reperfusion injury.Methods Thirty rabbits were randomized into three groups. Group ischemia-reperfusion (IR) (n=10) were anesthetized rabbits subjected to 30-minute occlusion of the left anterior descending coronary artery followed by 180-minute reperfusion. Group RPostC (n=10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion, and the left anterior descending coronary artery (LAD) occluded for 30 minutes with a 180-minute reperfusion. Group L-Nw-nitro-L-arginine methylester (L-NAME) + RPostC (n=10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion and intravenous infusion of L-NAME (10 mg/kg), and the LAD occluded for 30 minutes with a 180-minute reperfusion. Blood samples were taken for levels of creatine kinase (CK),superoxide dismutase (SOD) and malondialdehyde (MDA) at three different time points. At the end of the experiment,tissue samples of the infarcted region were harvested to calculate the cardiomyocyte apoptosis index (Al) by TUNEL. A piece of left and right lung tissue was harvested to evaluate the damage to the lung.Results After reperfusion for 180 minutes, the concentration of CK was lower in group RPostC, (4.79±0.27) U/ml, than that in group IR, (6.23±0.55) U/ml (P <0.01), and group L-NAME + RPsotC, (5.86±0.42) U/ml (P <0.01). The concentration of MDA was lower in group RPostC, (6.06±0.36) nmol/ml, than that in group IR, (11.41±0.91) nmol/ml (P <0.01), and group L-NAME + RPostC, (11.06±0.62) nmol/ml (P<0.01). The activity of SOD was higher in group RPostC,(242.34±25.02) U/ml, than that in group IR, (148.05±18.24) U/ml (P<0.01), and group L-NAME + RPostC, (160.66±9.55) U/ml (P<0.01). The apoptosis index was lower in

  15. Effect of Shenfu injection on nuclear factor-kB during myocardial ischemia/reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ben-jing; WANA Yan-lin; WANG Cheng-yao; KE Jian-juan

    2005-01-01

    Objective: To investigate effects of Shenfu injection on the concentrations of plasma tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), activity of Nuclear Factor kappa B (NF-κB) and heart tissue ultrastructure during myocardial ischemia/reperfusion (I/R) injury in rats and its potential mechanism.Methods: Myocardial ischemia/reperfusion (I/R) was produced by ligation and release of the left anterior descending coronary artery. Ischemia lasted for 30 min and reperfusion for 60 min. Twenty-four healthy male SD rats weighing 230-280 g were randomly divided into three groups (n=8, each): Group I (Sham-operation group); Group II (I/R group); Group III (Shenfu group), in which Shenfu injection (10 ml/kg) was intraperitoneally injected 30 min before ischemia in animals with I/R. The plasma concentrations of IL-6 and TNF-α were measured by ELISA, and the heart was harvested for determination of NF-κB levels by Ecl-western blot analysis. Electron microscopy was used to study its ultrastructure.Results: After reperfusion, NF-κB binding activity in myocardial nuclei and the plasma concentrations of IL-6 and TNF-α were significantly increased in Group II, compared with Group I (P<0.01), and they were markedly reduced in Group III, compared with Group II (P<0.01). In addition, electron microscopic examination showed more serious injury of the myocardium ultrastructure in Group II, while in Group III the myocardial ultrastructure was similar to normal state.Conclusions: Shenfu injection inhibits NF-κB activity in I/R myocardium and leads to down-regulation of proinflammatory cytokine expression, which might be one of the molecular mechanisms of Shenfu injection in cardioprotection.

  16. Protective effects of sitagliptin on myocardial injury and cardiac function in an ischemia/reperfusion rat model.

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    Chang, Guanglei; Zhang, Peng; Ye, Lin; Lu, Kai; Wang, Ying; Duan, Qin; Zheng, Aihua; Qin, Shu; Zhang, Dongying

    2013-10-15

    The purpose of this study is to investigate the effects and the underlying mechanisms of sitagliptin pretreatment on myocardial injury and cardiac function in myocardial ischemia/reperfusion (I/R) rat model. The rat model of myocardial I/R was constructed by coronary occlusion. Rats were pretreated with sitagliptin (300 mg/kg/day) for 2 weeks, and then subjected to 30 min ischemia and 2h reperfusion. The release of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), cardiac function and cardiomyocyte apoptosis were evaluated. The levels of malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in heart and glucagon-like peptide-1 (GLP-1) level in plasma were measured. Western blot analysis was performed to detect the target proteins of sitagliptin. Our results showed that sitagliptin pretreatment decreased LDH and CK-MB release, and MDA level in I/R rats. More importantly, we revealed for the first time that sitagliptin pretreatment decreased cardiomyocyte apoptosis while increased the levels of GSH-Px and SOD in heart. Sitagliptin also increased GLP-1 level and enhanced cardiac function in I/R rats. Furthermore, sitagliptin pretreatment up-regulated Akt(serine473) and Bad(serine136) phosphorylation, reduced the ratio of Bax/Bcl-2, and decreased expression levels of cleaved caspase-3 and caspase-3. Interestingly, the above observed effects of sitagliptin were all abolished when co-administered with GLP-1 receptor antagonist exendin-(9-39) or PI3K inhibitor LY294002. Taken together, our data indicate that sitagliptin pretreatment could reduce myocardial injury and improve cardiac function in I/R rats by reducing apoptosis and oxidative damage. The underlying mechanism might be the activation of PI3K/Akt signaling pathway by GLP-1/GLP-1 receptor. Crown Copyright © 2013 Published by Elsevier B.V. All rights reserved.

  17. Nebivolol protects against myocardial infarction injury via stimulation of beta 3-adrenergic receptors and nitric oxide signaling.

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    Zheng Zhang

    Full Text Available Nebivolol, third-generation β-blocker, may activate β3-adrenergic receptor (AR, which has been emerged as a novel and potential therapeutic targets for cardiovascular diseases. However, it is not known whether nebivolol administration plays a cardioprotective effect against myocardial infarction (MI injury. Therefore, the present study was designed to clarify the effects of nebivolol on MI injury and to elucidate the underlying mechanism. MI model was constructed by left anterior descending (LAD artery ligation. Nebivolol, β3-AR antagonist (SR59230A, Nitro-L-arginine methylester (L-NAME or vehicle was administered for 4 weeks after MI operation. Cardiac function was monitored by echocardiography. Moreover, the fibrosis and the apoptosis of myocardium were assessed by Masson's trichrome stain and TUNEL assay respectively 4 weeks after MI. Nebivolol administration reduced scar area by 68% compared with MI group (p<0.05. Meanwhile, nebivolol also decreased the myocardial apoptosis and improved the heart function after MI (p<0.05 vs. MI. These effects were associated with increased β3-AR expression. Moreover, nebivolol treatment significantly increased the phosphorylation of endothelial NOS (eNOS and the expression of neuronal NOS (nNOS. Conversely, the cardiac protective effects of nebivolol were abolished by SR and L-NAME. These results indicate that nebivolol protects against MI injury. Furthermore, the cardioprotective effects of nebivolol may be mediated by β3-AR-eNOS/nNOS pathway.

  18. Comparative analysis of different cyclosporine A doses on protection after myocardial ischemia/reperfusion injury in rat

    Institute of Scientific and Technical Information of China (English)

    Kang Huang; Shi-Juan Lu; Jiang-Hua Zhong; Qun Xiang; Liu Wang; Miao Wu

    2014-01-01

    Objective:To investigate the protective effect of different cyclosporinA(CsA) doses on myocardial ischemia/reperfusion injury in rat models.Methods:A rat model of myocardial ischemia/reperfusion injury was established in vivoand the rats were randomly divided into four groups: placebo(PBS;T1), low-dose(CsA dose:1.0 mg/kg;T2), medium-dose(CsA dose:2.5 mg/kg;T3), and high-dose(CsA dose:5.0 mg/kg;T4) groups.Heart function indexes were monitored at different time points, the extent of myocardial infarction was assessed byEvans Blue-TTC staining, and creatine kinase MB mass and cardiac troponinI values were measured by biochemical assays.Results:Compared with theT1 andT2 groups, both the creatine kinase MB mass and cardiac troponinI were significantly lower in theT3 andT4 groups(P<0.05).The mean arterial pressure(MAP) and left ventricular systolic pressure(LVSP) decreased sequentially in each group, with the extending reperfusion time.Significant decreases inLVSP andMAP were observed in theT3 andT4 groups as compared to theT1 andT2 group(P<0.05), and theT2 group showed a significantly lowerLVSP andMAP decline than theT1 group(P<0.05).Compared with theT1 group, the rats from theT2,T3, andT4 groups suffered from a significantly lower extent of myocardial infarction(P<0.05).Also, the animals in theT3 andT4 groups had a significantly smaller extent of myocardial infarction than those in theT2 group(P<0.05).Conclusions:Various CsA doses exert different degrees of protection against ischemia/reperfusion injury, and this protective effect peaks at approximately2.5 mg/kg in rat models.

  19. Study on Effect of Shenmai Injection Protecting Myocardium against Ischemia-Reperfusion Injury in Thrombolytic Therapy with Urokinase for Acute Myocardial Infarction Patient Evaluated by 99mTc-MIBI Myocardial Imaging

    Institute of Scientific and Technical Information of China (English)

    郭松鹏; 张言镇

    2001-01-01

    Objective: To evaluate the myocardial protecting effect of Shenmai injection (SMI) against ischemia/reperfusion injury in thrombolytic therapy with urokinase (UK) for acute myocardial infarction patients by 99mTc-MIBI myocardial imaging (SPECT). Methods: Five hundred and thirty-seven patients were divided into two groups randomly. The SMI group (n=292) was treated with thrombolytictreatment plus SMI and the control group (n=245) with thrombolytic treatment solely. Single photon emission computed tomography (SPECT) was carried out on the 7th day after thrombolysis to determine the ischemic myocardial area (IMA) and ejection fraction (EF) in both groups and compared. Results: The infarction related area (IRA) of reperfusion rate in the two groups was not different significantly (72.26% vs 72.65%, P >0.05). The IMA in patients of the SMI group, no matter with or without reperfused IRA (211 cases and 81 cases) respectively, was significantly lower than that in the control group (178 cases and 67 cases) respectively, P<0.01 and P<0.05 respectively. The EF value in the SMI group was significantly higher than that in the control group (P<0.01). Conclusion:Using SMI in early stage of thrombolytic treatment in acute myocardial infarction could significantly reduce IMA and increase EF. SMI showed good protective effect against myocardial ischemia/reperfusion injury in thrombolytic treatment.

  20. Study on Effect of Shenmai Injection Protecting Myocardium against Ischemia-Reperfusion Injury in Thrombolytic Therapy with Urokinase for Acute Myocardial Infarction Patient Evaluated by 99mTc-MIBI Myocardial Imaging

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To evaluate the myocardial protecting effect of Shenmai injection (SMI) against ischemia/reperfusion injury in thrombolytic therapy with urokinase (UK) for acute myocardial infarction patients by 99mTc-MIBI myocardial imaging (SPECT). Methods: Five hundred and thirty-seven patients were divided into two groups randomly. The SMI group (n=292) was treated with thrombolytictreatment plus SMI and the control group (n=245) with thrombolytic treatment solely. Single photon emission computed tomography (SPECT) was carried out on the 7th day after thrombolysis to determine the ischemic myocardial area (IMA) and ejection fraction (EF) in both groups and compared. Results: The infarction related area (IRA) of reperfusion rate in the two groups was not different significantly (72.26% vs 72.65%, P >0.05). The IMA in patients of the SMI group, no matter with or without reperfused IRA (211 cases and 81 cases) respectively, was significantly lower than that in the control group (178 cases and 67 cases) respectively, P<0.01 and P<0.05 respectively. The EF value in the SMI group was significantly higher than that in the control group (P<0.01). Conclusion:Using SMI in early stage of thrombolytic treatment in acute myocardial infarction could significantly reduce IMA and increase EF. SMI showed good protective effect against myocardial ischemia/reperfusion injury in thrombolytic treatment.

  1. The impact of a single episode of remote ischemic preconditioning on myocardial injury after elective percutaneous coronary intervention

    Science.gov (United States)

    Taylan, Gökay; Aktoz, Meryem; Gürlertop, Hanefi Y.; Aksoy, Yüksel; Özçelik, Fatih; Yalta, Kenan; Ekuklu, Galip

    2017-01-01

    Introduction Myocardial injury after percutaneous coronary intervention (PCI) occurs in approximately 30% of procedures, and is related to worse prognosis. Effects of remote ischemic preconditioning (RIPC) on reperfusion injury have been investigated before, yielding conflicting results. Aim To assess the impact of a single episode of RIPC on myocardial injury after elective PCI. Material and methods One hundred and four patients undergoing elective PCI, with normal baseline cardiac troponin-I (cTn-I) values, were randomized to two groups. Two patients were excluded due to data loss, and 102 patients were analyzed. Five minutes of ischemic preconditioning was delivered just before the intervention to the preconditioning group, by inflating the blood pressure cuff up to 200 mm Hg on the non-dominant arm. Postprocedural 16th hour cTn-I, ΔcTn-I (difference between the 16th h and baseline cTn-I values) and the prevalence of type 4a myocardial infarction were compared between the two groups. Results Median cTn-I values after the procedure were compared. 16th hour cTn-I was insignificantly lower in the preconditioning arm (0.026 μg/l vs. 0.045 μg/l, p = 0.186). The incidence of cTn-I elevation 5-fold above the upper reference limit (URL) (> 0.115 μg/l) was lower in the preconditioning group, but it was also not significant (21.6% vs. 11.8%, p = 0.184). Conclusions A single episode of RIPC before elective PCI demonstrated less troponin elevation but failed to show a significant effect. PMID:28344616

  2. Seabuckthorn Pulp Oil Protects against Myocardial Ischemia–Reperfusion Injury in Rats through Activation of Akt/eNOS

    Science.gov (United States)

    Suchal, Kapil; Bhatia, Jagriti; Malik, Salma; Malhotra, Rajiv Kumar; Gamad, Nanda; Goyal, Sameer; Nag, Tapas C.; Arya, Dharamvir S.; Ojha, Shreesh

    2016-01-01

    Seabuckthorn (SBT) pulp oil obtained from the fruits of seabuckthorn [Hippophae rhamnoides L. (Elaeagnaceae)] has been used traditionally for its medicinal and nutritional properties. However, its role in ischemia–reperfusion (IR) injury of myocardium in rats has not been elucidated so far. The present study reports the cardioprotective effect of SBT pulp oil in IR-induced model of myocardial infarction in rats and underlying mechanism mediating activation of Akt/eNOS signaling pathway. Male albino Wistar rats were orally administered SBT pulp oil (5, 10, and 20 ml/kg/day) or saline for 30 days. On the day 31, ischemia was induced by one-stage ligation of left anterior descending coronary artery for 45 min followed by reperfusion for 60 min. SBT pulp oil pretreatment at the dose of 20 ml/kg observed to stabilize cardiac function and myocardial antioxidants such as glutathione, superoxide dismutase, catalase, and inhibited lipid peroxidation evidenced by reduced malondialdehyde levels as compared to IR-control group. SBT pulp oil also improved hemodynamic and contractile function and decreased tumor necrosis factor and activities of myocyte injury marker enzymes; lactate dehydrogenase and creatine kinase-MB. Additionally, a remarkable rise in expression of pAkt–eNOS, Bcl-2 and decline in expression of IKKβ/NF-κB and Bax was observed in the myocardium. The histopathological and ultrastructural salvage of cardiomyocytes further supports the cardioprotective effect of SBT pulp oil. Based on findings, it can be concluded that SBT pulp oil protects against myocardial IR injury mediating favorable modulation of Akt-eNOS and IKKβ/NF-κB expression. PMID:27445803

  3. Berberine Attenuates Myocardial Ischemia/Reperfusion Injury by Reducing Oxidative Stress and Inflammation Response: Role of Silent Information Regulator 1

    Directory of Open Access Journals (Sweden)

    Liming Yu

    2016-01-01

    Full Text Available Berberine (BBR exerts potential protective effect against myocardial ischemia/reperfusion (MI/R injury. Activation of silent information regulator 1 (SIRT1 signaling attenuates MI/R injury by reducing oxidative damage and inflammation response. This study investigated the antioxidative and anti-inflammatory effects of BBR treatment in MI/R condition and elucidated its potential mechanisms. Sprague-Dawley rats were treated with BBR in the absence or presence of the SIRT1 inhibitor sirtinol (Stnl and then subjected to MI/R injury. BBR conferred cardioprotective effects by improving postischemic cardiac function, decreasing infarct size, reducing apoptotic index, diminishing serum creatine kinase and lactate dehydrogenase levels, upregulating SIRT1, Bcl-2 expressions, and downregulating Bax and caspase-3 expressions. Stnl attenuated these effects by inhibiting SIRT1 signaling. BBR treatment also reduced myocardium superoxide generation, gp91phox expression, malondialdehyde (MDA level, and cardiac inflammatory markers and increased myocardium superoxide dismutase (SOD level. However, these effects were also inhibited by Stnl. Consistently, BBR conferred similar antioxidative and anti-inflammatory effects against simulated ischemia reperfusion injury in cultured H9C2 cardiomyocytes. SIRT1 siRNA administration also abolished these effects. In summary, our results demonstrate that BBR significantly improves post-MI/R cardiac function recovery and reduces infarct size against MI/R injury possibly due to its strong antioxidative and anti-inflammatory activity. Additionally, SIRT1 signaling plays a key role in this process.

  4. Hyperlipidemia does not prevent the cardioprotection by postconditioning against myocardial ischemia/reperfusion injury and the involvement of hypoxia inducible factor-1α upregulation

    Institute of Scientific and Technical Information of China (English)

    Huanxin Zhao; Yehong Wang; Ye Wu; Xiaoyu Li; Guangzhao Yang; Xiurui Ma; gongrui Zhao; Huirong Liu

    2009-01-01

    Hyperlipidemia is regarded as an independent risk factor in the development of ischemic heart disease, and it can increase the myocardial susceptibility to ischemia/reperfusion (I/R) injury, lschemic postcondi-tioning (Postcon) has been demonstrated to attenuate the myocardial injury induced by I/R in normal con-ditions. But the effect of ischemic Postcon on hyperlipi-demic animals is unknown. Hypoxia inducible factor-1 (HIF-1) has been demonstrated to play a central role in the cardioprotection by preconditioning, which is one of the protective strategies except for Postcon. The aim of this study was to determine whether Postcon could reduce myocardial injury in hyperlipidemic animals and to assess whether HIF-1 was involved in Postcon mechanisms. Male Wistar rats underwent the left anterior descending coronary occlusion for 30 min fol-lowed by 180 min of reperfusion with or without Postcon after fed with high fat diet or normal diet for 8 weeks. The detrimental indices induced by the I/R insult included infarct size, plasma creatine kinase activity and caspase-3 activity. Results showed that hyperlipidemia remarkably enhanced the myocardial injury induced by I/R, while Postcon significantly decreased the myocardial injury in both normolipi-demic and hyperlipidemic rats. Moreover, both hyperli-pidemia and IfR promoted the HIF-1α expression. Most importantly, we have for the first time demon-strated that Postcon further induced a significant increase in HIF-1α protein level not only in normolipi-demic but also in hyperlipidemic conditions. Thus, Postcon reduces the myocardial injury induced by I/R in normal and hyperlipidemic animals, and HIF-1αupregulation may involve in the Postcon-mediated car-dioprotective mechanisms.

  5. Perioperative changes of ventricular function and three indicators of myocardial injury during orthotopic liver transplantation

    Institute of Scientific and Technical Information of China (English)

    HEI Zi-qing; LIU De-zhao; LUO Chen-fang; LI Shang-rong; MA Wu-hua; LUO Gang-jian

    2006-01-01

    @@ Patients undergoing orthotopic liver transplantation may develop significant haemodynamic instability, especially during anhepatic phase and immediately after reperfusion of the graft. The haemodynamic instability may be caused directly by myocardial depression due to pathogenic substances released from the liver, or by acute blood loss.1 Creatine kinase(CK) and its MB fraction (CK-MB) are sensitive and specific indicators to reflect myocardial damage.2 Cardiac troponin I (cTnl) is a specific and sensitive marker of myocardial necrosis.3 This study assessed perioperative cardiac function using three indicators (CK,CK-MB,and CTnl) to evaluate perioperative myocardial damage.$4This study was supported by grants from the National Natural Science Foundation of China (No. 30271254) and Guangdong Medical Development Foundation (No. 2004B35001005).

  6. Continuous renal replacement therapy (CRRT) attenuates myocardial inflammation and mitochondrial injury induced by venovenous extracorporeal membrane oxygenation (VV ECMO) in a healthy piglet model.

    Science.gov (United States)

    Shen, Juanhong; Yu, Wenkui; Chen, Qiyi; Shi, Jialiang; Hu, Yimin; Zhang, Juanjuan; Gao, Tao; Xi, Fengchan; He, Changsheng; Gong, Jianfeng; Li, Ning; Li, Jieshou

    2013-10-01

    In this study, we investigated the myocardial inflammation and mitochondrial function during venovenous extracorporeal membrane oxygenation (VV ECMO) and further evaluated the effects of continuous renal replacement therapy (CRRT) on them. Eighteen piglets were assigned to the control group, ECMO group, and ECMO+CRRT group. Myocardial inflammation was assessed by the activity of myeloperoxidase (MPO), myocardial concentrations, and mRNA expression of TNF-α, IL-1β, and IL-6; mitochondrial function was assessed by activities of mitochondrial complexes I-V. VV ECMO elicited a general activation of serum and myocardial inflammation and significantly decreased the activities of mitochondrial complexes I and IV. After being combined with CRRT, serum and myocardial concentrations of IL-1β and IL-6, myocardial mRNA expression of IL-6, and the activity of MPO were decreased significantly; the activities of mitochondrial complexes were increased. We conclude that myocardial inflammation was activated during ECMO therapy, inducing mitochondrial injury; moreover, CRRT reduced myocardial inflammation and partially ameliorated mitochondrial function.

  7. Haemodynamic collapse in a patient with acute inferior myocardial infarction and concomitant traumatic acute spinal cord injury.

    Science.gov (United States)

    Kumagai, Naoto; Dohi, Kaoru; Tanigawa, Takashi; Ito, Masaaki

    2013-11-22

    A 71-year-old man suddenly collapsed and went into cardiopulmonary arrest. The cardiopulmonary resuscitation attempt succeeded in restoration of spontaneous circulation. The initial 12-lead electrocardiogram showed inferior acute myocardial infarction (AMI). The patient was initially diagnosed as having cardiogenic shock associated with inferior AMI. In spite of early coronary revascularisation, bradycardia and hypotension were sustained. After termination of sedation and extubation, he was found to have a quadriplegia and diagnosed with a cervical spinal cord injury (SCI). Therefore, the patient was finally diagnosed with neurogenic shock caused by acute cervical SCI due to the traumatic injury preceded by loss of consciousness complicating inferior AMI. We should recognise that SCI has unique haemodynamic features that mimic those associated with inferior AMI, but requires very different treatment.

  8. Effect of monoamine nervous transmitter and neuropeptide Y in the aged rats with myocardial injury after brain ischemia-reperfusion

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To study the mechanism of myocardial injury after brain ischemia-reperfusion in aged rats from the changes in Dopamine (DA), Noradrenalin (NE), Epinephrine(E) and Neuropeptide Y(NPY).METHODS: Young (5 months) and aged (20 months or more) rats were divided into model groups and normal control groups, respectively. We observed the following items in rats with 60 minute reperfusion after 30 minute brain ischemia: the pathological changed of myocardium, the activities of lactic dehydrrogenase(LDH), creatine phosphokinase(CPK), the contents of NE, DA, E, NPY. RESULTS:The CPK and LDH activities in the young model rats were higher than those in the young control rats was higher than that in the young control rats (P<0.05). The serum CPK activity in the aged control rats was higher than that in the young control rats (P<0.05). The myocardial CPK activity was higher in the aged model rats compared with the young molel rats (P<0.05) and was higher in aged control rats compared with the young control rats (P<0.01). The myocardial LDH activity was lower in the aged control rats than that in the young control rats (P<0.05) and aged model rats (P<0.01). The serum NE level, the level of NE and DA in the hypothalamus were higher obviously than those in the young control rats. The serum NE contents in the two model groups (young and aged) were higher respectively than the two control rats (young and aged). The following items’ contents were higher in the aged model rats than in the young model rats: serum NE, serum E, hypothalamus NE. The hypothalamus NE and E content was lower in the aged model rats than in te aged control rats. NPY level in the brain tissue was lower in the aged control rats than that in the young control rats and aged model rats (P<0.05).CONCLUSION: The myocardial injury after brain ischemia-reperfusion was concerned with the enhanced excitability of sympathetic-adrenal system, espectially in the aged rats. However, the change in myocardial

  9. Paracrine systems in the cardioprotective effect of angiotensin-converting enzyme inhibitors on myocardial ischemia/reperfusion injury in rats.

    Science.gov (United States)

    Liu, Y H; Yang, X P; Sharov, V G; Sigmon, D H; Sabbath, H N; Carretero, O A

    1996-01-01

    After transient episodes of ischemia, benefits of thrombolytic or angioplastic therapy may be limited by reperfusion injury. Angiotensin-converting enzyme inhibitors protect the heart against ischemia/reperfusion injury, an effect mediated by kinins. We examined whether the protective effect of the angiotensin-converting enzyme inhibitor ramiprilat on myocardial ischemia/reperfusion is due to kinin stimulation of prostaglandin and/or nitric oxide release. The left anterior descending coronary artery of Lewis inbred rats was occluded for 30 minutes, followed by 120 minutes of reperfusion. Immediately before reperfusion rats were treated with vehicle, ramiprilat, or the angiotensin II type 1 receptor antagonist losartan. We tested whether pretreatment with the kinin receptor antagonist Hoe 140, the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester, or the cyclooxygenase inhibitor indomethacin blocked the effect of ramiprilat on infarct size and reperfusion arrhythmias. In controls, infarct size as a percentage of the area at risk was 79 +/- 3%; ramiprilat reduced this to 49 +/- 4% (P < .001), but losartan had little effect (74 +/- 6%, P = NS). Pretreatment with Hoe 140, NG-nitro-L-arginine methyl ester, or indomethacin abolished the beneficial effect of ramiprilat. Compared with the 30-minute ischemia/120-minute reperfusion group, nonreperfused hearts with 30 minutes of ischemia had significantly smaller infarct size as a percentage of the area at risk, whereas in the 150-minute ischemia group it was significantly larger. This suggests that reperfusion caused a significant part of the myocardial injury, but it also suggests that compared with prolonged ischemia, reperfusion salvaged some of the myocardium. Ventricular arrhythmias mirrored the changes in infarct size. Thus, angiotensin-converting enzyme inhibitors protect the myocardium against ischemia/reperfusion injury and arrhythmias; these beneficial effects are mediated primarily by a kinin

  10. Evaluation of the relationship between hyperinsulinaemia and myocardial ischaemia/reperfusion injury in a rat model of depression.

    Science.gov (United States)

    Solskov, Lasse; Løfgren, Bo; Pold, Rasmus; Kristiansen, Steen B; Nielsen, Torsten T; Overstreet, David H; Schmitz, Ole; Bøtker, Hans Erik; Lund, Sten; Wegener, Gregers

    2009-11-09

    Major depression is associated with medical co-morbidity, such as ischaemic heart disease and diabetes, but the underlying pathophysiological mechanisms remain unclear. The FSL (Flinders Sensitive Line) rat is a genetic animal model of depression exhibiting features similar to those of depressed individuals. The aim of the present study was to compare the myocardial responsiveness to I/R (ischaemia/reperfusion) injury and the effects of IPC (ischaemic preconditioning) in hearts from FSL rats using SD (Sprague-Dawley) rats as controls and to characterize differences in glucose metabolism and insulin sensitivity between FSL and SD rats. Hearts were perfused in a Langendorff model and were subjected or not to IPC before 40 min of global ischaemia, followed by 120 min of reperfusion. Myocardial infarct size was found to be significantly larger in the FSL rats than in the SD rats following I/R injury (62.4+/-4.2 compared with 46.9+/-2.9%; P<0.05). IPC reduced the infarct size (P<0.01) and improved haemodynamic function (P<0.01) in both FSL and SD rats. No significant difference was found in blood glucose levels between the two groups measured after 12 h of fasting, but fasting plasma insulin (70.1+/-8.9 compared with 40.9+/-4.7 pmol/l; P<0.05) and the HOMA (homoeostatic model assessment) index (P<0.01) were significantly higher in FSL rats compared with SD rats. In conclusion, FSL rats had larger infarct sizes following I/R injury and were found to be hyperinsulinaemic compared with SD rats, but appeared to have a maintained cardioprotective mechanism against I/R injury, as IPC reduced infarct size in these rats. This animal model may be useful in future studies when examining the mechanisms that contribute to the cardiovascular complications associated with depression.

  11. Gaseous hydrogen sulfide protects against myocardial ischemia-reperfusion injury in mice partially independent from hypometabolism.

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    Pauline M Snijder

    Full Text Available BACKGROUND: Ischemia-reperfusion injury (IRI is a major cause of cardiac damage following various pathological processes. Gaseous hydrogen sulfide (H2S is protective during IRI by inducing a hypometabolic state in mice which is associated with anti-apoptotic, anti-inflammatory and antioxidant properties. We investigated whether gaseous H2S administration is protective in cardiac IRI and whether non-hypometabolic concentrations of H2S have similar protective properties. METHODS: Male C57BL/6 mice received a 0, 10, or 100 ppm H2S-N2 mixture starting 30 minutes prior to ischemia until 5 minutes pre-reperfusion. IRI was inflicted by temporary ligation of the left coronary artery for 30 minutes. High-resolution respirometry equipment was used to assess CO2-production and blood pressure was measured using internal transmitters. The effects of H2S were assessed by histological and molecular analysis. RESULTS: Treatment with 100 ppm H2S decreased CO2-production by 72%, blood pressure by 14% and heart rate by 25%, while treatment with 10 ppm H2S had no effects. At day 1 of reperfusion 10 ppm H2S showed no effect on necrosis, while treatment with 100 ppm H2S reduced necrosis by 62% (p<0.05. Seven days post-reperfusion, both 10 ppm (p<0.01 and 100 ppm (p<0.05 H2S showed a reduction in fibrosis compared to IRI animals. Both 10 ppm and 100 ppm H2S reduced granulocyte-influx by 43% (p<0.05 and 60% (p<0.001, respectively. At 7 days post-reperfusion both 10 and 100 ppm H2S reduced expression of fibronectin by 63% (p<0.05 and 67% (p<0.01 and ANP by 84% and 63% (p<0.05, respectively. CONCLUSIONS: Gaseous administration of H2S is protective when administered during a cardiac ischemic insult. Although hypometabolism is restricted to small animals, we now showed that low non-hypometabolic concentrations of H2S also have protective properties in IRI. Since IRI is a frequent cause of myocardial damage during percutaneous coronary intervention and cardiac

  12. The uremic toxin adsorbent AST-120 abrogates cardiorenal injury following myocardial infarction.

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    Suree Lekawanvijit

    Full Text Available An accelerated progressive decline in renal function is a frequent accompaniment of myocardial infarction (MI. Indoxyl sulfate (IS, a uremic toxin that accumulates from the early stages of chronic kidney disease (CKD, is contributory to both renal and cardiac fibrosis. IS levels can be reduced by administration of the oral adsorbent AST-120, which has been shown to ameliorate pathological renal and cardiac fibrosis in moderate to severe CKD. However, the cardiorenal effect of AST-120 on less severe renal dysfunction in the post-MI setting has not previously been well studied. MI-induced Sprague-Dawley rats were randomized to receive either AST-120 (MI+AST-120 or were untreated (MI+Vehicle for 16 weeks. Serum IS levels were measured at baseline, 8 and 16 weeks. Echocardiography and glomerular filtration rate (GFR were assessed prior to sacrifice. Renal and cardiac tissues were assessed for pathological changes using histological and immunohistochemical methods, Western blot analysis and real-time PCR. Compared with sham, MI+Vehicle animals had a significant reduction in left ventricular ejection fraction (by 42%, p<0.001 and fractional shortening (by 52%, p<0.001 as well as lower GFR (p<0.05 and increased serum IS levels (p<0.05. A significant increase in interstitial fibrosis in the renal cortex was demonstrated in MI+Vehicle animals (p<0.001. Compared with MI+Vehicle, MI+AST-120 animals had increased GFR (by 13.35%, p<0.05 and reduced serum IS (p<0.001, renal interstitial fibrosis (p<0.05, and renal KIM-1, collagen-IV and TIMP-1 expression (p<0.05. Cardiac function did not change with AST-120 treatment, however gene expression of TGF-β1 and TNF-α as well as collagen-I and TIMP-1 protein expression was decreased in the non-infarcted myocardium (p<0.05. In conclusion, reduction of IS attenuates cardio-renal fibrotic processes in the post-MI kidney. KIM-1 appears to be a sensitive renal injury biomarker in this setting and is correlated with

  13. Role of speckle tracking imaging in the assessment of myocardial regional ventricular function in experimental blunt cardiac injury

    Institute of Scientific and Technical Information of China (English)

    Wen-Hua Du; Xiang Wang; Xiu-Qin Xiong; Tao Li; Hua-Ping Liang

    2015-01-01

    Purpose:To evaluate the usefulness and information collecting ability of speckle tracking imaging techniques in the assessment of myocardial regional ventricular contractility in a rabbit model with blunt cardiac injury.Methods:Fifteen healthy New Zealand rabbits weighing (2.70 ± 0.28) kg were anesthetized (3% pentobarbital sodium/i.v) and impacted using the BIM-Ⅱ biological impact machine to induce myocardial contusion (MC).Hemodynamic parameters,such as heart rate,systolic pressure,mean arterial pressure,diastolic pressure and central venous pressure,were determined before and after MC.Further,parameters reflecting left ventricular functions,such as left ventricular end systolic pressure,left ventricular end diastolic pressure,isovolumic pressure (IP) and the maximal increasing/decreasing rate of left intraventricular pressure (±dp/dtmax),were also determined before and after MC.Left ventricular functions were determined either by two dimensional transthoracic echocardiography or by speckle tracking imaging for segmental abnormal ventricular wall motions.Results:Heart rate,systolic pressure,diastolic pressure and mean arterial pressure decreased significantly but transiently,while central venous pressure markedly increased after MC.In contrast to significant changes in diastolic functions,there was no significant change in cardiac systolic functions after MC.The speckle tracking imaging demonstrated that strain values of different myocardial segment significantly decreased post impact,and that of the ventricular segment decreased from segment to segment.Conclusion:Speckle tracking imaging is useful and informative to assess myocardial regional dysfunctions post MC.

  14. Protection of rutaecarpine against myocardial ischemia—reperfusion injury in rats:possible involvement of vanilloid receptors

    Institute of Scientific and Technical Information of China (English)

    HuCP; LiNS

    2002-01-01

    Previous investigations have shown that calcitonin gen-related peptide(CGRP) protects against myocardial ischemia-reperfusion injury and that rutaecarpine activates vanilloid receptors to evoke CGRP release.In the present study,SD rats were pretreated with rutaecarpine 10min before the experiment,and then the left main coronary artery was subjected to 60min occlusion followed by 3h reperfusion.Pretreatment with rutaecarpine(100 or 300μg·kg-1,iv) significantly reduced infarce size and creatine kinase release concomitantly with a significant increase in plasma concentrations of CGPR.These effects of rutaecarpine were completely abolished by pretreatment with capsazepine(38mg·kg-1,ic),a competitive vanilloid receptor antagonist or capsaicin (50mg·kg-1,sc),which selectively depletes transmitters in capsaicin-sensitive sensory nerves.These results suggest that the kprotection of rutaecarpine against myocardial ischemia-reperfusion injury is due to stimulation of endogenous CGRP release via activating vanilloid receptors in rats.

  15. Iloprost and vitamin C attenuates acute myocardial injury induced by suprarenal aortic ischemia-reperfusion in rabbits.

    Science.gov (United States)

    Iriz, E; Iriz, A; Take, G; Ozgul, H; Oktar, L; Demirtas, H; Helvacioglu, F; Arslan, M

    2015-01-01

    The aim of this study was to evaluate antioxidant and cytoprotective effects of iloprost and Vitamin C in a distant organ after abdominal aorta ischemia-reperfusion injury. Twenty-eight New Zealand rabbits weighing 2,400-2,800 g were used for this study. The rabbits were divided into four equal groups. These groups are control group, sham group, iloprost group, and iloprost+vitamin C group. Suprarenal aorta was occluded with a vascular clamp. Following 30 minutes of ischemia, the vascular clamp was removed. Rabbits in group 3 received 10 ng/kg/min iloprost and those in group 4 received 10 ng/kg/min iloprost and 10 mg/kg vitamin C. At the end of the reperfusion period, the rabbits were sacrificed by a high intraperitoneal dose of xylazine+ketamine injection. Myocardial tissue samples were taken for electron microscopic analysis. We evaluated SOD, MDA and catalase in myocardial tissue samples. Iloprost and iloprost+vitamin C groups significantly reduced the oxidative stress markers in tissue samples (pvitamin C administration (pvitamin C showed an attenuation of ischemia-reperfusion injury in distant organs (Tab. 3, Fig. 4, Ref. 30).

  16. Synergistic myoprotection of L-arginine and adenosine in a canine model of global myocardial ischaemic reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    DU Lei; DIAN Ke; CHEN Hui-jiao; AN Qi; JIA Meng-xing; YANG Ping-liang; WANG Wei; DENG Shuo-zeng; LIU Jin

    2007-01-01

    Background Endogenous nitric oxide and adenosine increase simultaneously to keep the balance of energy demand and supply when the oxygen supply is insufficient, which suggests that nitric oxide and adenosine might exert a synergistic myoprotection during tissue hypoxia. In this study, we tested this hypothesis utilizing a canine model of prolonged global myocardial ischaemic reperfusion injury.Methods In this double blind, controlled study, the hearts of 24 anaesthetized mongrel dogs were arrested for 2 hours with aortic cross clamping and blood cardioplegia. The treatment groups were those supplemented with 2 mmol/L L-arginine (ARG), supplemented with 1 mmol/L adenosine (ADO), ARG + ADO supplemented with both, and no supplementation (control) (n=6 in each group). Haemodynamics, biochemical indices, adenosine triphosphate (ATP) content and myeloperoxidase activities of myocardium were determined to evaluate myocardial injury. Statistical comparison was performed by two way ANOVA.Results Although the requirements for inotropic supports were higher, the cardiac outputs were lower in control group than in ARG, ADO and the combination groups. Plasma cardiac troponin I levels were higher and the areas of hydropic changes were larger in control group than in ARG and ADO groups. Combination of arginine and adenosine provided further myoprotection with respect to better cardiac performance, lower release of cardiac troponin I, and smaller areas of hydropic changes compared with ARG and ADO groups. ATP content was higher, but myeloperoxidase activities of myocardium were significantly lower in the combination group than in control, ARG and ADO groups (P<0.05).Conclusions Combination of L-arginine and adenosine provides synergistic myoprotection in a canine model of global myocardial ischaemia. Thus, the combination is recommended when the heart is exposed to a prolonged ischaemia during cardiac surgery.

  17. CPU0213, a novel endothelin type A and type B receptor antagonist, protects against myocardial ischemia/reperfusion injury in rats

    Directory of Open Access Journals (Sweden)

    Z.Y. Wang

    2011-11-01

    Full Text Available The efficacy of endothelin receptor antagonists in protecting against myocardial ischemia/reperfusion (I/R injury is controversial, and the mechanisms remain unclear. The aim of this study was to investigate the effects of CPU0123, a novel endothelin type A and type B receptor antagonist, on myocardial I/R injury and to explore the mechanisms involved. Male Sprague-Dawley rats weighing 200-250 g were randomized to three groups (6-7 per group: group 1, Sham; group 2, I/R + vehicle. Rats were subjected to in vivo myocardial I/R injury by ligation of the left anterior descending coronary artery and 0.5% sodium carboxymethyl cellulose (1 mL/kg was injected intraperitoneally immediately prior to coronary occlusion. Group 3, I/R + CPU0213. Rats were subjected to identical surgical procedures and CPU0213 (30 mg/kg was injected intraperitoneally immediately prior to coronary occlusion. Infarct size, cardiac function and biochemical changes were measured. CPU0213 pretreatment reduced infarct size as a percentage of the ischemic area by 44.5% (I/R + vehicle: 61.3 ± 3.2 vs I/R + CPU0213: 34.0 ± 5.5%, P < 0.05 and improved ejection fraction by 17.2% (I/R + vehicle: 58.4 ± 2.8 vs I/R + CPU0213: 68.5 ± 2.2%, P < 0.05 compared to vehicle-treated animals. This protection was associated with inhibition of myocardial inflammation and oxidative stress. Moreover, reduction in Akt (protein kinase B and endothelial nitric oxide synthase (eNOS phosphorylation induced by myocardial I/R injury was limited by CPU0213 (P < 0.05. These data suggest that CPU0123, a non-selective antagonist, has protective effects against myocardial I/R injury in rats, which may be related to the Akt/eNOS pathway.

  18. Insights for Oxidative Stress and mTOR Signaling in Myocardial Ischemia/Reperfusion Injury under Diabetes

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    Dajun Zhao

    2017-01-01

    Full Text Available Diabetes mellitus (DM displays a high morbidity. The diabetic heart is susceptible to myocardial ischemia/reperfusion (MI/R injury. Impaired activation of prosurvival pathways, endoplasmic reticulum (ER stress, increased basal oxidative state, and decreased antioxidant defense and autophagy may render diabetic hearts more vulnerable to MI/R injury. Oxidative stress and mTOR signaling crucially regulate cardiometabolism, affecting MI/R injury under diabetes. Producing reactive oxygen species (ROS and reactive nitrogen species (RNS, uncoupling nitric oxide synthase (NOS, and disturbing the mitochondrial quality control may be three major mechanisms of oxidative stress. mTOR signaling presents both cardioprotective and cardiotoxic effects on the diabetic heart, which interplays with oxidative stress directly or indirectly. Antihyperglycemic agent metformin and newly found free radicals scavengers, Sirt1 and CTRP9, may serve as promising pharmacological therapeutic targets. In this review, we will focus on the role of oxidative stress and mTOR signaling in the pathophysiology of MI/R injury in diabetes and discuss potential mechanisms and their interactions in an effort to provide some evidence for cardiometabolic targeted therapies for ischemic heart disease (IHD.

  19. Insights for Oxidative Stress and mTOR Signaling in Myocardial Ischemia/Reperfusion Injury under Diabetes

    Science.gov (United States)

    Zhao, Dajun

    2017-01-01

    Diabetes mellitus (DM) displays a high morbidity. The diabetic heart is susceptible to myocardial ischemia/reperfusion (MI/R) injury. Impaired activation of prosurvival pathways, endoplasmic reticulum (ER) stress, increased basal oxidative state, and decreased antioxidant defense and autophagy may render diabetic hearts more vulnerable to MI/R injury. Oxidative stress and mTOR signaling crucially regulate cardiometabolism, affecting MI/R injury under diabetes. Producing reactive oxygen species (ROS) and reactive nitrogen species (RNS), uncoupling nitric oxide synthase (NOS), and disturbing the mitochondrial quality control may be three major mechanisms of oxidative stress. mTOR signaling presents both cardioprotective and cardiotoxic effects on the diabetic heart, which interplays with oxidative stress directly or indirectly. Antihyperglycemic agent metformin and newly found free radicals scavengers, Sirt1 and CTRP9, may serve as promising pharmacological therapeutic targets. In this review, we will focus on the role of oxidative stress and mTOR signaling in the pathophysiology of MI/R injury in diabetes and discuss potential mechanisms and their interactions in an effort to provide some evidence for cardiometabolic targeted therapies for ischemic heart disease (IHD).

  20. Translational Medicine Study on Cardiac Microvascular Endothelial Barrier Function and Myocardial Ischemia/Re-perfusion Injury

    Institute of Scientific and Technical Information of China (English)

    Yeong Yeh Lee

    2015-01-01

    Vascular endothelial barrier is defined as the ability of endothelial cells and their components that make up the microvascular wall structure in controlling the cellular components and marco-molecular substances in blood from penetrating vascular walls. It is the place for the selective exchange of oxygen, nutrients and metabolites, and has kernel effect in maintaining myocardial micro-environmental homeostasis. In clinic, microvascular permeability is commonly used as the index for evaluating endothelial barrier function. Myocardial microvascular endothelial cells, inter-endothelial connexin and basilar membrane (BM) interact synergically to constitute the basis for barrier function, which has a selective permeability effect on interaction between nutrient substances and other myocardial cell molecules. Increase of microvascular permeability is closely associated with cardiovascular events like coronary heart disease (CHD) and myocardial ischemia, and is the risk factor for CHD attack. And deep exploration of the mechanism of endothelial permeability and positive selection of new-type re-perfusion complementary drugs for alleviating endothelial permeability can be beneifcial in improving the prognosis of patients with acute myocardial infarction (AMI). Therefore, from the view of translational medicine, this study mainly summarized the increase of microvascular permeability and its pathological signiifcance after AMI, physiological and pathological mechanisms of regulating microvascular permeability and complementary therapies for AMI re-perfusion as well as microvascular endothelial barrier function, hoping to provide a basis for improving the prognosis of patients with AMI.

  1. Translational Medicine Study on Cardiac Microvascular Endothelial Barrier Function and Myocardial Ischemia/Re-perfusion Injury

    Directory of Open Access Journals (Sweden)

    Yeong Yeh Lee

    2015-09-01

    Full Text Available Vascular endothelial barrier is defined as the ability of endothelial cells and their components that make up the microvascular wall structure in controlling the cellular components and marco-molecular substances in blood from penetrating vascular walls. It is the place for the selective exchange of oxygen, nutrients and metabolites, and has kernel effect in maintaining myocardial micro-environmental homeostasis. In clinic, microvascular permeability is commonly used as the index for evaluating endothelial barrier function. Myocardial microvascular endothelial cells, inter-endothelial connexin and basilar membrane (BM interact synergically to constitute the basis for barrier function, which has a selective permeability effect on interaction between nutrient substances and other myocardial cell molecules. Increase of microvascular permeability is closely associated with cardiovascular events like coronary heart disease (CHD and myocardial ischemia, and is the risk factor for CHD attack. And deep exploration of the mechanism of endothelial permeability and positive selection of new-type re-perfusion complementary drugs for alleviating endothelial permeability can be beneficial in improving the prognosis of patients with acute myocardial infarction (AMI. Therefore, from the view of translational medicine, this study mainly summarized the increase of microvascular permeability and its pathological significance after AMI, physiological and pathological mechanisms of regulating microvascular permeability and complementary therapies for AMI re-perfusion as well as microvascular endothelial barrier function, hoping to provide a basis for improving the prognosis of patients with AMI.

  2. The PI3K/Akt pathway mediates the protection of SO2 preconditioning against myocardial ischemia/reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Man-man ZHAO; Jin-yan YANG; Xin-bao WANG; Chao-shu TANG; Jun-bao DU; Hong-fang JIN

    2013-01-01

    Aim:To explore the mechanisms underlying the protection by SO2 preconditioning against rat myocardial ischemia/reperfusion (I/R)injury.Methods:Male Wistar rats underwent 30-min left coronary artery ligation followed by 120-min reperfusion.An S02 donor (1 μmol/kg)was intravenously injected 10 min before the ischemia,while LY294002 (0.3 mg/kg) was intravenously injected 30 min before the ischemia.Plasma activities of LDH and CK were measured with an automatic enzyme analyzer.Myocardial infarct size was detected using Evans-TTC method.The activities of caspase-3 and-9 in myocardium were assayed using a commercial kit,and the levels of p-Akt,Akt,P13K and p-P13K were examined with Western blotting.Results:Pretreatment with SO2 significantly reduced the myocardial infarct size and plasma LDH and CK activities,as well as myocardial caspase-3 and-9 activities in the rats.Furthermore,the pretreatment significantly increased the expression levels of myocardial p-Akt and p-PI3K p85.Administration of the PI3K inhibitor LY294002 blocked all the effects induced by SO2 pretreatment.Conclusion:The results suggest that the PI3K/Akt pathway mediates the protective effects of SO2 preconditioning against myocardial I/R injury in rats.

  3. Cardiomyocyte-specific overexpression of an active form of Rac predisposes the heart to increased myocardial stunning and ischemia-reperfusion injury

    Science.gov (United States)

    Talukder, M. A. Hassan; Elnakish, Mohammad T.; Yang, Fuchun; Nishijima, Yoshinori; Alhaj, Mazin A.; Velayutham, Murugesan; Hassanain, Hamdy H.

    2013-01-01

    The GTP-binding protein Rac regulates diverse cellular functions including activation of NADPH oxidase, a major source of superoxide production (O2·−). Rac1-mediated NADPH oxidase activation is increased after myocardial infarction (MI) and heart failure both in animals and humans; however, the impact of increased myocardial Rac on impending ischemia-reperfusion (I/R) is unknown. A novel transgenic mouse model with cardiac-specific overexpression of constitutively active mutant form of Zea maize Rac D (ZmRacD) gene has been reported with increased myocardial Rac-GTPase activity and O2·− generation. The goal of the present study was to determine signaling pathways related to increased myocardial ZmRacD and to what extent hearts with increased ZmRacD proteins are susceptible to I/R injury. The effect of myocardial I/R was examined in young adult wild-type (WT) and ZmRacD transgenic (TG) mice. In vitro reversible myocardial I/R for postischemic cardiac function and in vivo regional myocardial I/R for MI were performed. Following 20-min global ischemia and 45-min reperfusion, postischemic cardiac contractile function and heart rate were significantly reduced in TG hearts compared with WT hearts. Importantly, acute regional myocardial I/R (30-min ischemia and 24-h reperfusion) caused significantly larger MI in TG mice compared with WT mice. Western blot analysis of cardiac homogenates revealed that increased myocardial ZmRacD gene expression is associated with concomitant increased levels of NADPH oxidase subunit gp91phox, O2·−, and P21-activated kinase. Thus these findings provide direct evidence that increased levels of active myocardial Rac renders the heart susceptible to increased postischemic contractile dysfunction and MI following acute I/R. PMID:23161879

  4. Irreversible processes kinetic theory

    CERN Document Server

    Brush, Stephen G

    2013-01-01

    Kinetic Theory, Volume 2: Irreversible Processes deals with the kinetic theory of gases and the irreversible processes they undergo. It includes the two papers by James Clerk Maxwell and Ludwig Boltzmann in which the basic equations for transport processes in gases are formulated, together with the first derivation of Boltzmann's ""H-theorem"" and a discussion of this theorem, along with the problem of irreversibility.Comprised of 10 chapters, this volume begins with an introduction to the fundamental nature of heat and of gases, along with Boltzmann's work on the kinetic theory of gases and s

  5. Development of ST Elevation Myocardial Infarction and Atrial Fibrillation after an Electrical Injury

    Directory of Open Access Journals (Sweden)

    Erdal Gursul

    2015-01-01

    Full Text Available Electrical energy is a type of energy that is commonly used in daily life. Ventricular premature beats, ventricular tachycardia, ventricular fibrillation, atrial tachycardia, atrial fibrillation, bundle branch blocks, and AV block are arrhythmic complications that are encountered in case of electric shocks. Myocardial infarction is one of the rarely seen complications of electric shocks yet it has fatal outcomes. Coronary arteries were detected to be normal in most of the patients who had myocardial infarction following an electric shock. So, etiology of myocardial infarction is thought to be unrelated to coronary atherosclerosis in these cases. Coronary artery vasospasm is thought to be the primary etiological cause. In our case report, we presented a patient who developed ST elevation MI with atrial fibrillation after an electric shock.

  6. Evaluation of cardioprotective effect of aqueous extract of Allium cepa Linn. bulb on isoprenaline-induced myocardial injury in Wistar albino rats.

    Science.gov (United States)

    Kharadi, Geeta B; Patel, Kaksha J; Purohit, Bhargav M; Baxi, Seema N; Tripathi, C B

    2016-10-01

    To investigate the cardioprotective potential of the aqueous extract of Allium cepa Linn. bulb in isoprenaline-induced myocardial injury in Wistar albino rats. In vitro total phenolic, total flavonoid content and 2, 2'-diphenyl-1-picrylhydrazyl hydrate radical scavenging activity was measured. Isoprenaline-induced myocardial injury model was used to evaluate in vivo effect of aqueous extract of A. cepa in Wistar albino rats. Seventy two rats were randomly divided in 6 groups. Rats were treated with A. cepa 400 mg/kg and 800 mg/kg doses for 30 days and myocardial injury was produced by subcutaneous injection of isoprenaline (ISO) 85 mg/kg on day 28 and 29. Carvedilol 1 mg/kg for 30 days served as active control. Electrocardiogram parameters, cardiac injury markers, oxidative stress markers and histopathological changes were evaluated in each group and compared using appropriate statistical tests. In vitro evaluation of aqueous extract of A. cepa showed significant antioxidant property. ISO produced significant myocardial injury as compared to normal control group (P cepa in the dose of 400 mg/kg significantly recovered the altered parameters (Troponin-I, Creatine kinase-MB, glutamate-pyruvate transaminase, HR, R-R interval, and oxidative stress markers) compared to disease control group (P cepa in the dose 800 mg/kg recovered the altered parameters (HR, heart weight/body weight ratio, and superoxide dismutase level) compared to disease control group. Histopathological parameters did not recover in the doses of 400 and 800 mg/kg (P > 0.05). The aqueous extract of A. cepa 400 mg/kg was found to be cardioprotective against myocardial injury while A. cepa 800 mg/kg did not show significant cardioprotective activity. So, we presume that A. cepa might be effective within certain dose range only.

  7. MicroRNA-15a/b are up-regulated in response to myocardial ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Li-Feng Liu; Zhuo Liang; Zhen-Rong Lv; Xiu-Hua Liu; Jing Bai; Jie Chen; Chen Chen; Yu Wang

    2012-01-01

    Objective Several studies have indicated that miR-15a,miR-15b and miR-16 may be the important regulators of apoptosis.Since attenuate apoptosis could protect myocardium and reduce infarction size,the present study was aimed to find out whether these miRNAs participate in regulating myocardial ischemia reperfusion (I/R) injury.Methods Apoptosis in mice hearts subjected to I/R was detected by TUNEL assay in vivo,while flow cytometry analysis followed by Annexin V/PI double stain in vitro was used to detect apoptosis in cultured cardiomyocytes which were subjected to hypoxia/reoxygenation (H/R).Taqman real-time quantitative PCR was used to confirm whether miR-15a/15b/16 were involved in the regulation of cardiac I/R and H/R.Results Compared to those of the controls,I/R or H/R induced apoptosis of cardiomyocytes was significantly iucreased both in vivo (24.4% ± 9.4% vs.2.2% ± 1.9%,P < 0.01,n =5) and in vitro (14.12% ±0.92% vs.2.22% ± 0.08%).The expression of miR-15a and miR-15b,but not miR-16,was increased in the mice I/R model,and the results were consistent in the H/R model.Conclusions Our data indicate miR-15 and miR-15b are up-regulated in response to cardiac I/R injury,therefore,down-regulation of miR- 15a/b may be a promising strategy to reduce myocardial apoptosis induced by cardiac I/R injury.

  8. N-acetylcysteine and allopurinol synergistically enhance cardiac adiponectin content and reduce myocardial reperfusion injury in diabetic rats.

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    Tingting Wang

    Full Text Available BACKGROUND: Hyperglycemia-induced oxidative stress plays a central role in the development of diabetic myocardial complications. Adiponectin (APN, an adipokine with anti-diabetic and anti-ischemic effects, is decreased in diabetes. It is unknown whether or not antioxidant treatment with N-acetylcysteine (NAC and/or allopurinol (ALP can attenuate APN deficiency and myocardial ischemia reperfusion (MI/R injury in the early stage of diabetes. METHODOLOGY/PRINCIPAL FINDINGS: Control or streptozotocin (STZ-induced diabetic rats were either untreated (C, D or treated with NAC (1.5 g/kg/day or ALP (100 mg/kg/day or their combination for four weeks starting one week after STZ injection. Plasma and cardiac biochemical parameters were measured after the completion of treatment, and the rats were subjected to MI/R by occluding the left anterior descending artery for 30 min followed by 2 h reperfusion. Plasma and cardiac APN levels were decreased in diabetic rats accompanied by decreased cardiac APN receptor 2 (AdipoR2, reduced phosphorylation of Akt, signal transducer and activator of transcription 3 (STAT3 and endothelial nitric oxide synthase (eNOS but increased IL-6 and TNF-α (all P<0.05 vs. C. NAC but not ALP increased cardiac APN concentrations and AdipoR2 expression in diabetic rats. ALP enhanced the effects of NAC in restoring cardiac AdipoR2 and phosphorylation of Akt, STAT3 and eNOS in diabetic rats. Further, NAC and ALP, respectively, decreased postischemic myocardial infarct size and creatinine kinase-MB (CK-MB release in diabetic rats, while their combination conferred synergistic protective effects. In addition, exposure of cultured rat cardiomyocytes to high glucose resulted in significant reduction of cardiomyocyte APN concentration and AdipoR2 protein expression. APN supplementation restored high glucose induced AdipoR2 reduction in cardiomyocytes. CONCLUSIONS/SIGNIFICANCE: NAC and ALP synergistically restore myocardial APN and AdipoR2

  9. Cardioprotective effects of salidroside on myocardial ischemia-reperfusion injury in coronary artery occlusion-induced rats and Langendorff-perfused rat hearts.

    Science.gov (United States)

    Chang, Xiayun; Zhang, Kai; Zhou, Rui; Luo, Fen; Zhu, Lingpeng; Gao, Jin; He, He; Wei, Tingting; Yan, Tianhua; Ma, Chunhua

    2016-07-15

    The current study was designed to investigate the protective role of salisroside on rats through the study of energy metabolism homeostasis and inflammation both in ex vivo and in vivo. Energy metabolism homeostasis and inflammation injury were respectively assessed in global ischemia of isolated hearts and coronary artery ligated rats. Excessive release of cardiac enzymes and pro-inflammatory cytokines was inhibited by salidroside in coronary artery occlusion-induced rats. ST segment was also restored with the treatment of salidroside. Triphenyltetrazolium chloride staining (TTC) staining and pathological analysis showed that salidroside could significantly alleviate myocardial injury in vivo. Accumulated data in ex vivo indicated that salidroside improved heart function recovery, which was reflected by enhanced myocardial contractility and coronary flow in isolated hearts. The contents of ATP and glycogen both in ex vivo and in vivo were restored by salidroside compared with those in the model group. Besides, the expressions of p-AMPK, PPAR-α and PGC-1α in rats and isolated hearts subjected to salidroside were significantly elevated, while the levels of p-NF-κBp65, p-IκBα, p-IKKα and p-IKKβ were dramatically reduced by salidroside. The present study comprehensively elaborated the protective effects of salidroside on myocardial injury and demonstrated that AMPK/PGC-1α and AMPK/NF-κB signaling cascades were implicated in the myocardial ischemia-reperfusion injury (I/R) model. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Primary PCI and Treatment of Reperfusion Injury in Acute Myocardial Infarction

    NARCIS (Netherlands)

    M.T. Dirksen (Maurits)

    2008-01-01

    textabstractAcute myocardial infarction (AMI) is responsible for the majority of (sudden) deaths and significant morbidity, thereby causing a major burden on health care. The prognosis of patients after an AMI is mainly determined by the size of the infarct, which is dependent of the area at risk (d

  11. Suppression of Excessive Histone Deacetylases Activity in Diabetic Hearts Attenuates Myocardial Ischemia/Reperfusion Injury via Mitochondria Apoptosis Pathway

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    Yang Wu

    2017-01-01

    Full Text Available Background. Histone deacetylases (HDACs play a pivotal role in signaling modification and gene transcriptional regulation that are essential for cardiovascular pathophysiology. Diabetic hearts with higher HDACs activity were more vulnerable to myocardial ischemia/reperfusion (MI/R injury compared with nondiabetic hearts. We are curious about whether suppression of excessive HDACs activity in diabetic heart protects against MI/R injury. Methods. Diabetic rats were subjected to 45 min of ischemia, followed by 3 h of reperfusion. H9C2 cardiomyocytes were exposed to high glucose for 24 h, followed by 4 h of hypoxia and 2 h of reoxygenation (H/R. Results. Both MI/R injury and diabetes mellitus elevated myocardium HDACs activity. MI/R induced apoptotic cell death was significantly decreased in diabetic rats treated with HDACs inhibitor trichostatin A (TSA. TSA administration markedly moderated dissipation of mitochondrial membrane potential, protected the integrity of mitochondrial permeability transition pore (mPTP, and decreased cell apoptosis. Notably, cotreatment with Akt inhibitor partly or absolutely inhibited the protective effect of TSA in vivo and in vitro. Furthermore, TSA administration activated Akt/Foxo3a pathway, leading to Foxo3a cytoplasm translocation and attenuation proapoptosis protein Bim expression. Conclusions. Both diabetes mellitus and MI/R injury increased cardiac HDACs activity. Suppression of HDACs activity triggered protective effects against MI/R and H/R injury under hyperglycemia conditions through Akt-modulated mitochondrial apoptotic pathways via Foxo3a/Bim.

  12. Suppression of Excessive Histone Deacetylases Activity in Diabetic Hearts Attenuates Myocardial Ischemia/Reperfusion Injury via Mitochondria Apoptosis Pathway

    Science.gov (United States)

    Wu, Yang; Leng, Yan; Meng, Qingtao; Xue, Rui; Zhao, Bo; Zhan, Liying

    2017-01-01

    Background. Histone deacetylases (HDACs) play a pivotal role in signaling modification and gene transcriptional regulation that are essential for cardiovascular pathophysiology. Diabetic hearts with higher HDACs activity were more vulnerable to myocardial ischemia/reperfusion (MI/R) injury compared with nondiabetic hearts. We are curious about whether suppression of excessive HDACs activity in diabetic heart protects against MI/R injury. Methods. Diabetic rats were subjected to 45 min of ischemia, followed by 3 h of reperfusion. H9C2 cardiomyocytes were exposed to high glucose for 24 h, followed by 4 h of hypoxia and 2 h of reoxygenation (H/R). Results. Both MI/R injury and diabetes mellitus elevated myocardium HDACs activity. MI/R induced apoptotic cell death was significantly decreased in diabetic rats treated with HDACs inhibitor trichostatin A (TSA). TSA administration markedly moderated dissipation of mitochondrial membrane potential, protected the integrity of mitochondrial permeability transition pore (mPTP), and decreased cell apoptosis. Notably, cotreatment with Akt inhibitor partly or absolutely inhibited the protective effect of TSA in vivo and in vitro. Furthermore, TSA administration activated Akt/Foxo3a pathway, leading to Foxo3a cytoplasm translocation and attenuation proapoptosis protein Bim expression. Conclusions. Both diabetes mellitus and MI/R injury increased cardiac HDACs activity. Suppression of HDACs activity triggered protective effects against MI/R and H/R injury under hyperglycemia conditions through Akt-modulated mitochondrial apoptotic pathways via Foxo3a/Bim. PMID:28191472

  13. Application of combined determination of myocardial injury markers in early diagnosis of myocardial infarction%心肌损伤标志物联合检测在早期诊断心肌梗死中的应用

    Institute of Scientific and Technical Information of China (English)

    朱应才

    2014-01-01

    Objective To investigate the value of combined determination of myocardial injury markers in the early diagnosis of myocardial infarction. Methods A total of 100 patients with a suspected diagnosis of acute myocardial infarction who were admitted to our hospital from June 2011 to June 2014 were divided into experimental group (n=60, with acute myocardial infarction) and control group (n=40, without acute myocardial infarction). Combined determination of myocardial injury markers was performed. Results The experimental group had significantly higher levels of cardiac troponin I (cTnl), myoglobin (Myo), creatine kinase-MB, and creatine kinase than the control group (P﹤0.05). In the experimental group, Myo had the highest early sensitivity, while cTnI had the highest specificity. Conclusion Myocardial injury markers play an important role in the diagnosis of acute myocardial infarction and hold promise for clinical application.%目的:探讨心肌损伤标志物联合检测在心肌梗死中的早期诊断价值。方法选取2011年6月~2014年6月入住我院的疑似急性心肌梗死患者100例,按照世界卫生组织标准将其分成实验组60例(急性心肌梗死),对照组40例(非急性心肌梗死),联合检测两组心肌损伤标志物。结果实验组 cTnl、MYO、CK-MB、CK 水平均高于对照组(P﹤0.05),实验组早期敏感性以 MYO 最高,特异性以 cTnl 最高。结论心肌损伤标志物在急性心肌梗死诊断中发挥着十分重要的作用,值得在临床上广泛应用,

  14. Merit of Anisodamine Combined with Opioid δ-Receptor Activation in the Protection against Myocardial Injury during Cardiopulmonary Bypass

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    Xuan Hong

    2013-01-01

    Full Text Available Myocardial ischemia/reperfusion (MIR injury easily occurrs during cardiopulmonary bypass surgery in elderly patients. In an attempt to develop an effective strategy, we employed a pig model of MIR injury to investigate the maximum rate of change of left ventricular pressure, left ventricular enddiastolic pressure, and left intraventricular pressure. Coronary sinus cardiac troponin T (TnT and adenosine-triphosphate (ATP content in myocardium were measured. The ultrastructures for MIR injury were visualized by transmission electron microscopy (TEM. The role of δ-opioid receptor activation using D-Ala2, D-Leu5-enkephalin (DADLE in both early (D1 and late (D2 phases of cardioprotection was identified. Also, the merit of cardioprotection by DADLE in combination with anisodamine, the muscarinic receptor antagonist (D+M, was evaluated. Glibenclamide was employed at the dose sufficient to block ATP-sensitive potassium channels. Significant higher cardiac indicators, reduced TnT and increased ATP contents, were observed in D1, D2, and D+M groups compared with the control group. DADLE induced protection was better in later phase of ischemia that was attenuated by glibenclamide. DADLE after the ischemia showed no benefit, but combined treatment with anisodamine showed a marked postischemic cardioprotection. Thus, anisodamine is helpful in combination with DADLE for postischemic cardioprotection.

  15. Human mannose-binding lectin inhibitor prevents myocardial injury and arterial thrombogenesis in a novel animal model.

    Science.gov (United States)

    Pavlov, Vasile I; Tan, Ying S; McClure, Erin E; La Bonte, Laura R; Zou, Chenhui; Gorsuch, William B; Stahl, Gregory L

    2015-02-01

    Myocardial infarction and coagulation disorders are leading causes of disability and death in the world. An important role of the lectin complement pathway in myocardial infarction and coagulation has been demonstrated in mice genetically deficient in lectin complement pathway proteins. However, these studies are limited to comparisons between wild-type and deficient mice and lack the ability to examine reversal/inhibition of injury after disease establishment. We developed a novel mouse that expresses functional human mannose-binding lectin (MBL) 2 under the control of Mbl1 promoter. Serum MBL2 concentrations averaged approximately 3 μg/mL in MBL2(+/+)Mbl1(-/-)Mbl2(-/-) [MBL2 knock in (KI)] mice. Serum MBL2 level in MBL2 KI mice significantly increased after 7 (8 μg/mL) or 14 (9 μg/mL) days of hyperglycemia compared to normoglycemic mice (P < 0.001). Monoclonal antibody 3F8 inhibited C3 deposition on mannan-coated plates in MBL2 KI, but not wild-type, mice. Myocardial ischemia/reperfusion in MBL2 KI mice revealed that 3F8 preserved cardiac function and decreased infarct size and fibrin deposition in a time-dependent manner. Furthermore, 3F8 prevented ferric chloride-induced occlusive arterial thrombogenesis in vivo. MBL2 KI mice represent a novel animal model that can be used to study the lectin complement pathway in acute and chronic models of human disease. Furthermore, these novel mice demonstrate the therapeutic window for MBL2 inhibition for effective treatment of disease and its complications.

  16. Impact of multi-vessel therapy to the risk of periprocedural myocardial injury after elective coronary intervention: exploratory study.

    Science.gov (United States)

    Chen, Zhang-Wei; Yang, Hong-Bo; Chen, Ying-Hua; Ma, Jian-Ying; Qian, Ju-Ying; Ge, Jun-Bo

    2017-02-27

    Periprocedural myocardial injury (PMI) after elective percutaneous coronary intervention (PCI) significantly influences the prognosis of coronary artery disease (CAD). However, it was unclear whether the occurrence of PMI was associated with a series of controllable factors, such as PCI strategy or severity of CAD. A total of 544 consecutive stable CAD patients underwent elective PCI were enrolled. The main outcome is PMI, defined as troponin T after PCI was at least one value above the 99th percentile upper reference limit. Major adverse cardiac events (MACE), including all-cause death, repeat myocardial infarction and target vessel revascularization were record in the period of follow-up. Univariate and multivariate analysis was applied to assess predictors for the occurrence of PMI. The incidence of PMI was 38.8% in the study. Compared with non-PMI patients (n = 333), PMI patients (n = 211) had more diseased vessels, higher Gensini and Syntax score. Meanwhile, there were higher incidence of MACE in PMI groups (9.5% vs. 3.2%, P PMI patients underwent higher proportion of multi-vessel PCI simultaneously (32.2% vs. 10.5%, P PMI was still increased 84% by multi-vessel PCI independently (OR = 1.654, 95% CI = 1.004-2.720, P PMI occurred more commonly in stable CAD patients underwent multi-vessel PCI. Multi-vessel international therapy could increase the risk of PMI in elective PCI.

  17. Quercetin postconditioning attenuates myocardial ischemia/reperfusion injury in rats through the PI3K/Akt pathway

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    Y. Wang

    2013-09-01

    Full Text Available Quercetin (Que, a plant-derived flavonoid, has multiple benefical actions on the cardiovascular system. The current study investigated whether Que postconditioning has any protective effects on myocardial ischemia/reperfusion (I/R injury in vivo and its potential cardioprotective mechanisms. Male Sprague-Dawley rats were randomly allocated to 5 groups (20 animals/group: sham, I/R, Que postconditioning, Que+LY294002 [a phosphatidylinositol 3-kinase (PI3K/Akt signaling pathway inhibitor], and LY294002+I/R. I/R was produced by 30-min coronary occlusion followed by 2-h reperfusion. At the end of reperfusion, myocardial infarct size and biochemical changes were compared. Apoptosis was evaluated by both TUNEL staining and measurement of activated caspase-3 immunoreactivity. The phosphorylation of Akt and protein expression of Bcl-2 and Bax were determined by Western blotting. Que postconditioning significantly reduced infarct size and serum levels of creatine kinase and lactate dehydrogenase compared with the I/R group (all P<0.05. Apoptotic cardiomyocytes and caspase-3 immunoreactivity were also suppressed in the Que postconditioning group compared with the I/R group (both P<0.05. Akt phosphorylation and Bcl-2 expression increased after Que postconditioning, but Bax expression decreased. These effects were inhibited by LY294002. The data indicate that Que postconditioning can induce cardioprotection by activating the PI3K/Akt signaling pathway and modulating the expression of Bcl-2 and Bax proteins.

  18. Quercetin postconditioning attenuates myocardial ischemia/reperfusion injury in rats through the PI3K/Akt pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Zhang, Z.Z.; Wu, Y.; Ke, J.J.; He, X.H.; Wang, Y.L. [Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Wuhan (China)

    2013-09-24

    Quercetin (Que), a plant-derived flavonoid, has multiple benefical actions on the cardiovascular system. The current study investigated whether Que postconditioning has any protective effects on myocardial ischemia/reperfusion (I/R) injury in vivo and its potential cardioprotective mechanisms. Male Sprague-Dawley rats were randomly allocated to 5 groups (20 animals/group): sham, I/R, Que postconditioning, Que+LY294002 [a phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway inhibitor], and LY294002+I/R. I/R was produced by 30-min coronary occlusion followed by 2-h reperfusion. At the end of reperfusion, myocardial infarct size and biochemical changes were compared. Apoptosis was evaluated by both TUNEL staining and measurement of activated caspase-3 immunoreactivity. The phosphorylation of Akt and protein expression of Bcl-2 and Bax were determined by Western blotting. Que postconditioning significantly reduced infarct size and serum levels of creatine kinase and lactate dehydrogenase compared with the I/R group (all P<0.05). Apoptotic cardiomyocytes and caspase-3 immunoreactivity were also suppressed in the Que postconditioning group compared with the I/R group (both P<0.05). Akt phosphorylation and Bcl-2 expression increased after Que postconditioning, but Bax expression decreased. These effects were inhibited by LY294002. The data indicate that Que postconditioning can induce cardioprotection by activating the PI3K/Akt signaling pathway and modulating the expression of Bcl-2 and Bax proteins.

  19. Direct evidence of endothelial injury in acute myocardial infarction and unstable angina by demonstration of circulating endothelial cells.

    Science.gov (United States)

    Mutin, M; Canavy, I; Blann, A; Bory, M; Sampol, J; Dignat-George, F

    1999-05-01

    Circulating endothelial cells (CECs) have been detected in association with endothelial injury and therefore represent proof of serious damage to the vascular tree. Our aim was to investigate, using the technique of immunomagnetic separation, whether the pathological events in unstable angina (UA) or acute myocardial infarction (AMI) could cause desquamation of endothelial cells in circulating blood compared with effort angina (EA) and noncoronary chest pain. A high CEC count was found in AMI (median, 7.5 cells/mL; interquartile range, 4.1 to 43.5, P chest pain as compared with controls (0; 0 to 0 cells/mL) and stable angina (0; 0 to 0 cells/mL). CEC levels in serial samples peaked at 15.5 (2.7 to 39) cells/mL 18 to 24 hours after AMI (P angina, confirming that these diseases have different etiopathogenic mechanisms.

  20. [The role of free radicals in the myocardial reperfusion injuries and in the development of endogenous adaptation].

    Science.gov (United States)

    Rőth, Erzsébet

    2015-11-22

    The reperfusion of acute ischaemic myocardium is essential for myocardial salvage, so-called "gold standard" therapy, however it can result in serious damage to the myocardium. Functional alterations occur, including depressed contractile function and decreased coronary flow as well as altered vascular reactivity. Over several decades it has been demonstrated that oxygen radical formation is greatly increased in the post-ischaemic heart and serves as a critical central mechanism of ischaemic-reperfusion injury. However it has been demonstrated that free radicals play an important role in the endogenous adaptation phenomenon of the heart, too. Ischaemic preconditioning is a cellular adaptive response of the heart to stress, which provides the most potent endogenous protection against reperfusion arrhytmias, stunning and infarction. Post-conditioning defined as brief periods of ischaemia and reperfusion during the very early minutes of reperfusion stimulates endogenous adaptation. Post-conditioning may also attenuate the damage to endothelial cells and cardiomyocytes from oxidants, cytokines, proteases and inflammatory cells.

  1. Exenatide reduces reperfusion injury in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Lønborg, Jacob; Vejlstrup, Niels; Kelbæk, Henning

    2011-01-01

    (STEMI) treated with primary percutaneous coronary intervention (pPCI). Methods and results A total of 172 patients with STEMI and Thrombolysis in Myocardial Infarction flow 0/1 were randomly assigned to exenatide or placebo (saline) intravenously. Study treatment was commenced 15 min before intervention...... the infarct size and the AAR for both treatment groups and an analysis of covariance showed that datapoints in the exenatide group lay significantly lower than for the placebo group (P= 0.011). There was a trend towards smaller absolute infarct size in the exenatide group (13 ± 9 vs. 17 ± 14 g; P= 0.......11). No difference was observed in left ventricular function or 30-day clinical events. No adverse effects of exenatide were observed. Conclusion In patients with STEMI undergoing pPCI, administration of exenatide at the time of reperfusion increases myocardial salvage....

  2. Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells Relieve Acute Myocardial Ischemic Injury

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    Yuanyuan Zhao

    2015-01-01

    Full Text Available This study is aimed at investigating whether human umbilical cord mesenchymal stem cell- (hucMSC- derived exosomes (hucMSC-exosomes have a protective effect on acute myocardial infarction (AMI. Exosomes were characterized under transmission electron microscopy and the particles of exosomes were further examined through nanoparticle tracking analysis. Exosomes (400 μg protein were intravenously administrated immediately following ligation of the left anterior descending (LAD coronary artery in rats. Cardiac function was evaluated by echocardiography and apoptotic cells were counted using TUNEL staining. The cardiac fibrosis was assessed using Masson’s trichrome staining. The Ki67 positive cells in ischemic myocardium were determined using immunohistochemistry. The effect of hucMSC-exosomes on blood vessel formation was evaluated through tube formation and migration of human umbilical vein endothelial cells (EA.hy926 cells. The results indicated that ligation of the LAD coronary artery reduced cardiac function and induced cardiomyocyte apoptosis. Administration of hucMSC-exosomes significantly improved cardiac systolic function and reduced cardiac fibrosis. Moreover, hucMSC-exosomes protected myocardial cells from apoptosis and promoted the tube formation and migration of EA.hy926 cells. It is concluded that hucMSC-exosomes improved cardiac systolic function by protecting myocardial cells from apoptosis and promoting angiogenesis. These effects of hucMSC-exosomes might be associated with regulating the expression of Bcl-2 family.

  3. Assessment of myocardial injury markers and neurohumoral indicators in serum after STEMI patients received percutaneous coronary intervention combined with thrombus aspiration

    Institute of Scientific and Technical Information of China (English)

    Ling Gong

    2016-01-01

    Objective:To study the myocardial injury markers and neurohumoral indicators in serum after STEMI patients received percutaneous coronary intervention combined with thrombus aspiration.Methods:Patients with acute ST-segment elevation myocardial infarction who received percutaneous coronary intervention in our hospital from May 2010 to December 2015 were selected for study, 48 cases of patients who received PCI combined with thrombus aspiration and 50 cases of patients who received direct PCI were screened and included in experimental group and control group respectively. The degree of myocardial injury and neurohumoral indicators of two groups were compared.Results:Intraoperative TIMI grade of experimental group was significantly higher than that of control group, peak values of CK-MB, cTnT and cTnI 24 h after operation were significantly lower than those of control group, and ST-segment fallback ratio within 1h after operation was significantly higher than that of control group; 24h after operation, serum renin, angiotensin II, aldosterone, sodium and endothlin-1 content of experimental group were significantly lower than those of control group, potassium and nitric oxide content were significantly higher than those of control group, and the number of CD31+/CD42b- EMPs in peripheral blood was significantly lower than that of control group. Conclusion:Percutaneous coronary intervention combined with thrombus aspiration treatment of STEMI can improve coronary perfusion, reduce myocardial cell injury, inhibit RAS system activation and protect endothelial function.

  4. Late cardioprotection of exercise preconditioning against exhaustive exercise-induced myocardial injury by up-regulatation of connexin 43 expression in rat hearts

    Institute of Scientific and Technical Information of China (English)

    Kai Wang; Bai-Chao Xu; Hai-Yun Duan; Hua Zhang; Fu-Song Hu

    2015-01-01

    Objective:To investigate the expression of myocardium connexin 43 (Cx43) in late exercise preconditioning (LEP) cardioprotection.Methods: Eight-week-old adult male Sprague Dawley rats were randomly assigned into four groups (n=8). Myocardial injury was judged in accordance with serum levels of cTnⅠ and NT-proBNP as well as hematoxylin basicfuchsin picric acid staining of myocardium.Cx43mRNA was detected byin situhybridization and qualified by real-time fluorescence quantitative PCR. Cx43 protein was localized by immunohistochemistry and its expression level was determined by western blotting.Results:The LEP obviously attenuated the myocardial ischemia/hypoxia injury caused by exhaustive exercise. There was no significant difference of Cx43mRNA level between the four groups. Cx43 protein level was decreased significantly in group EE (P<0.05). However, LEP produced a significant increase in Cx43 protein level (P<0.05), and the decreased Cx43 protein level in exhaustive exercise was significantly up-regulated by LEP (P<0.05).Conclusions:LEP protects rat heart against exhaustive exercise-induced myocardial injury by up-regulating the expression of myocardial Cx43.

  5. Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction by Biomarkers

    Science.gov (United States)

    2016-01-25

    Acute Myocardial Infarction (AMI); Acute Coronary Syndrome (ACS); ST Elevation (STEMI) Myocardial Infarction; Ischemic Reperfusion Injury; Non-ST Elevation (NSTEMI) Myocardial Infarction; Angina, Unstable

  6. Luteolin Inhibits Ischemia/Reperfusion-Induced Myocardial Injury in Rats via Downregulation of microRNA-208b-3p.

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    Chen Bian

    Full Text Available Luteolin (LUT, a kind of flavonoid which is extracted from a variety of diets, has been reported to convey protective effects of various diseases. Recent researches have suggested that LUT can carry out cardioprotective effects during ischemia/reperfusion (I/R. However, there have no reports on whether LUT can exert protective effects against myocardial I/R injury through the actions of specific microRNAs (miRs. The purpose of this study was to determine which miRs and target genes LUT exerted such function through.Expression of various miRs in perfused rat hearts was detected using a gene chip. Target genes were predicted with TargetScan, MiRDB and MiRanda. Anoxia/reoxygenation was used to simulate I/R. Cells were transfected by miR-208b-3p mimic, inhibitor and small interfering RNA of Ets1 (avian erythroblastosis virus E26 (v ets oncogene homolog 1. MiR-208b-3p and Ets1 mRNA were quantified by real-time quantitative polymerase chain reaction. The percentage of apoptotic cells was detected by annexin V-fluorescein isothiocyanate/propidium iodide dyeing and flow cytometry. The protein expression levels of cleaved caspase-3, Bcl-2, Bax, and Ets1 were examined by western blot analysis. A luciferase reporter assay was used to verify the combination between miR-208b-3p and the 3'-untranslated region of Ets1.LUT pretreatment reduced miR-208b-3p expression in myocardial tissue, as compared to the I/R group. And LUT decreased miR-208b-3p expression and apoptosis caused by I/R. However, overexpression of miR-208b-3p further aggravated the changes caused by I/R and blocked all the effects of LUT. Knockdown of miR-208b-3p expression also attenuated apoptosis, while knockdown of Ets1 promoted apoptosis. Further, the luciferase reporter assay showed that miR-208b-3p could inhibit Ets1 expression.LUT pretreatment conveys anti-apoptotic effects after myocardial I/R injury by decreasing miR-208b-3p and increasing Ets1 expression levels.

  7. Serum Fatty Acids, Traditional Risk Factors, and Comorbidity as Related to Myocardial Injury in an Elderly Population with Acute Myocardial Infarction

    DEFF Research Database (Denmark)

    Laake, Kristian; Seljeflot, Ingebjørg; Schmidt, Erik B;

    2016-01-01

    ), and peak Troponin T (TnT) levels in elderly patients with an acute myocardial infarction (AMI). Materials and Methods. Patients (n = 299) consecutively included in the ongoing Omega-3 fatty acids in elderly patients with myocardial infarction (OMEMI) trial were investigated. Peak TnT was registered during...

  8. THE ROLE OF MYOCARDIAL ISCHEMIC POSTCONDITIONING AND TOLL-LIKE RECEPTORS IN MYOCARDIAL REPERFUSION INJURY%心肌缺血后适应和Toll样受体在心肌再灌注损伤中的作用

    Institute of Scientific and Technical Information of China (English)

    王妮妮; 王悦喜

    2014-01-01

    近年来随着急性心肌梗死发病率的不断增高,促进了溶栓、经皮穿刺冠状动脉介入治疗和冠状动脉旁路移植术( CABG)等再灌注疗法的广泛开展,由缺血/再灌注损伤( ischemia/reperfusion injury,IRI)引起的心脏损伤日益受到重视。因此,研究减轻心肌缺血/再灌注损伤安全、有效的方法对防治心脏疾病具有重大的价值和意义。近期国内外很多研究发现心肌缺血后适应(ischemic postconditioning,IPOC)及 Toll 样受体(Toll like receptor,TRL)在心肌缺血再灌注损伤中起重要作用,本文对此进行综述。%In recent years,the thrombolysis,percutaneous coronary intervention and coronary artery bypass grafting( CABG) and other reperfusion therapy are widely developing with incidence increasing of acute myocardial infarction. Heart damage induced by the ischemia/reperfusion injury ( ischemia/reperfusion injury,IRI) is increasingly concerned. Therefore,the study of safe and effective method in reducing myocardial ischemia/reperfusion injury has great value and significance in the prevention of heart disease. Recently many domestic and foreign researches found that ischemic postconditioning (IPOC)and toll-like receptors(Toll like receptor,TRL)play important role in myocardial ischemia-reperfusion injury.

  9. Small-molecule-biased formyl peptide receptor agonist compound 17b protects against myocardial ischaemia-reperfusion injury in mice.

    Science.gov (United States)

    Qin, Cheng Xue; May, Lauren T; Li, Renming; Cao, Nga; Rosli, Sarah; Deo, Minh; Alexander, Amy E; Horlock, Duncan; Bourke, Jane E; Yang, Yuan H; Stewart, Alastair G; Kaye, David M; Du, Xiao-Jun; Sexton, Patrick M; Christopoulos, Arthur; Gao, Xiao-Ming; Ritchie, Rebecca H

    2017-02-07

    Effective treatment for managing myocardial infarction (MI) remains an urgent, unmet clinical need. Formyl peptide receptors (FPR) regulate inflammation, a major contributing mechanism to cardiac injury following MI. Here we demonstrate that FPR1/FPR2-biased agonism may represent a novel therapeutic strategy for the treatment of MI. The small-molecule FPR1/FPR2 agonist, Compound 17b (Cmpd17b), exhibits a distinct signalling fingerprint to the conventional FPR1/FPR2 agonist, Compound-43 (Cmpd43). In Chinese hamster ovary (CHO) cells stably transfected with human FPR1 or FPR2, Compd17b is biased away from potentially detrimental FPR1/2-mediated calcium mobilization, but retains the pro-survival signalling, ERK1/2 and Akt phosphorylation, relative to Compd43. The pathological importance of the biased agonism of Cmpd17b is demonstrable as superior cardioprotection in both in vitro (cardiomyocytes and cardiofibroblasts) and MI injury in mice in vivo. These findings reveal new insights for development of small molecule FPR agonists with an improved cardioprotective profile for treating MI.

  10. Incidence and mortality of acute kidney injury in acute myocardial infarction patients: a comparison between AKIN and RIFLE criteria.

    Science.gov (United States)

    Shacham, Yacov; Leshem-Rubinow, Eran; Ziv-Baran, Tomer; Gal-Oz, Amir; Steinvil, Arie; Ben Assa, Eyal; Keren, Gad; Roth, Arie; Arbel, Yaron

    2014-12-01

    Acute kidney injury (AKI) is associated with adverse outcomes after acute ST elevation myocardial infarction (STEMI). The recently proposed AKI network (AKIN) suggested modifications to the consensus classification system for AKI known as the risk, injury, failure, loss, end-stage (RIFLE) criteria. The aim of the current study was to compare the incidence and mortality (early and late) of AKI diagnosed by RIFLE and AKIN criteria in the STEMI patients undergoing primary percutaneous intervention (PCI). We retrospectively studied 1,033 consecutive STEMI patients undergoing primary PCI. Recruited patients were admitted between January 2008 and November 2012 to the cardiac intensive care unit with the diagnosis of acute STEMI. We compared the utilization of RIFLE and AKIN criteria for the diagnosis, classification, and prediction of mortality. The AKIN criteria allowed the identification of more patients as having AKI (9.6 vs. 3.9 %, p RIFLE) (7.6 vs. 1.9 %, p RIFLE criteria. Mortality was higher in AKI population defined by either RIFLE (46.3 vs. 6.8 %, OR 11.9, 95 % CI 6.15-23.1; p RIFLE and AKIN was an independent predictor of both 30-day and up to 5-year all-cause mortality. However, there was no significant statistical difference in the risk provided by these two scoring systems. AKIN criteria are more sensitive in defining AKI compared with the RIFLE criteria in STEMI. However, no difference exists in the mortality risk provided by these two scoring systems.

  11. Myocardial function at the early phase of traumatic brain injury: a prospective controlled study

    OpenAIRE

    Cuisinier, Adrien; Maufrais, Claire; Payen, Jean-François; Nottin, Stephane; Walther, Guillaume; Bouzat, Pierre

    2016-01-01

    Background The concept of brain-heart interaction has been described in several brain injuries. Traumatic brain injury (TBI) may also lead to cardiac dysfunction but evidences are mainly based upon experimental and clinical retrospective studies. Methods We conducted a prospective case-control study in a level I trauma center. Twenty consecutive adult patients with severe TBI were matched according to age and gender with 20 control patients. The control group included adult patients undergoin...

  12. Reduced silent information regulator 1 signaling exacerbates myocardial ischemia-reperfusion injury in type 2 diabetic rats and the protective effect of melatonin.

    Science.gov (United States)

    Yu, Liming; Liang, Hongliang; Dong, Xiaochao; Zhao, Guolong; Jin, Zhenxiao; Zhai, Mengen; Yang, Yang; Chen, Wensheng; Liu, Jincheng; Yi, Wei; Yang, Jian; Yi, Dinghua; Duan, Weixun; Yu, Shiqiang

    2015-10-01

    Diabetes mellitus (DM) increases myocardial oxidative stress and endoplasmic reticulum (ER) stress. Melatonin confers cardioprotective effect by suppressing oxidative damage. However, the effect and mechanism of melatonin on myocardial ischemia-reperfusion (MI/R) injury in type 2 diabetic state are still unknown. In this study, we developed high-fat diet-fed streptozotocin (HFD-STZ) rat, a well-known type 2 diabetic model, to evaluate the effect of melatonin on MI/R injury with a focus on silent information regulator 1 (SIRT1) signaling, oxidative stress, and PERK/eIF2α/ATF4-mediated ER stress. HFD-STZ treated rats were exposed to melatonin treatment in the presence or the absence of sirtinol (a SIRT1 inhibitor) and subjected to MI/R surgery. Compared with nondiabetic animals, type 2 diabetic rats exhibited significantly decreased myocardial SIRT1 signaling, increased apoptosis, enhanced oxidative stress, and ER stress. Additionally, further reduced SIRT1 signaling, aggravated oxidative damage, and ER stress were found in diabetic animals subjected to MI/R surgery. Melatonin markedly reduced MI/R injury by improving cardiac functional recovery and decreasing myocardial apoptosis in type 2 diabetic animals. Melatonin treatment up-regulated SIRT1 expression, reduced oxidative damage, and suppressed PERK/eIF2α/ATF4 signaling. However, these effects were all attenuated by SIRT1 inhibition. Melatonin also protected high glucose/high fat cultured H9C2 cardiomyocytes against simulated ischemia-reperfusion injury-induced ER stress by activating SIRT1 signaling while SIRT1 siRNA blunted this action. Taken together, our study demonstrates that reduced cardiac SIRT1 signaling in type 2 diabetic state aggravates MI/R injury. Melatonin ameliorates reperfusion-induced oxidative stress and ER stress via activation of SIRT1 signaling, thus reducing MI/R damage and improving cardiac function.

  13. Immediate, irreversible, posttraumatic coma: a review indicating that bilateral brainstem injury rather than widespread hemispheric damage is essential for its production.

    Science.gov (United States)

    Rosenblum, William I

    2015-03-01

    Traumatic brain injury may result in immediate long-lasting coma. Much attention has been given to predicting this outcome from the initial examination because these predictions can guide future treatment and interactions with the patient's family. Reports of diffuse axonal injury in these cases have ascribed the coma to widespread damage in the deep white matter that disconnects the hemispheres from the ascending arousal system (AAS). However, brainstem lesions are also present in such cases, and the AAS may be interrupted at the brainstem level. This review examines autopsy and imaging literature that assesses the presence, extent, and predictive value of lesions in both sites. The evidence suggests that diffuse injury to the deep white matter is not the usual cause of immediate long-lasting posttraumatic coma. Instead, brainstem lesions in the rostral pons or midbrain are almost always the cause but only if the lesions are bilateral. Moreover, recovery is possible if critical brainstem inputs to the AAS are spared. The precise localization of the latter is subject to ongoing investigation with advanced imaging techniques using magnets of very high magnetic gradients. Limited availability of this equipment plus the need to verify the findings continue to require meticulous autopsy examination.

  14. LncRNA NONRATT021972 involved the pathophysiologic processes mediated by P2X7 receptors in stellate ganglia after myocardial ischemic injury.

    Science.gov (United States)

    Zou, Lifang; Tu, Guihua; Xie, Wei; Wen, Shiyao; Xie, Qiuyu; Liu, Shuangmei; Li, Guilin; Gao, Yun; Xu, Hong; Wang, Shouyu; Xue, Yun; Wu, Bing; Lv, Qiulan; Ying, Mofeng; Zhang, Xi; Liang, Shangdong

    2016-03-01

    Adenosine triphosphate (ATP) acts on P2X receptors to initiate signal transmission. P2X7 receptors play a role in the pathophysiological process of myocardial ischemic injury. Long noncoding RNAs (lncRNAs) participate in numerous biological functions independent of protein translation. LncRNAs are implicated in nervous system diseases. This study investigated the effects of NONRATT021972 small interference RNA (siRNA) on the pathophysiologic processes mediated by P2X7 receptors in stellate ganglia (SG) after myocardial ischemic injury. Our results demonstrated that the expression of NONRATT021972 in SG was significantly higher in the myocardial ischemic (MI) group than in the control group. Treatment of MI rats with NONRATT021972 siRNA, the P2X7 antagonist brilliant blue G (BBG), or P2X7 siRNA improved the histology of injured ischemic cardiac tissues and decreased the elevated concentrations of serum myocardial enzymes, creatine kinase (CK), CK isoform MB (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) compared to the MI rats. NONRATT021972 siRNA, BBG, or P2X7 siRNA treatment in MI rats decreased the expression levels of P2X7 immunoreactivity, P2X7 messenger RNA (mRNA), and P2X7 protein, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) in the SG compared to MI rats. NONRATT021972 siRNA treatment prevented the pathophysiologic processes mediated by P2X7 receptors in the SG after myocardial ischemic injury.

  15. Attenuation of Myocardial Injury by HMGB1 Blockade during Ischemia/Reperfusion Is Toll-Like Receptor 2-Dependent

    Directory of Open Access Journals (Sweden)

    Jan Mersmann

    2013-01-01

    Full Text Available Genetic or pharmacological ablation of toll-like receptor 2 (TLR2 protects against myocardial ischemia/reperfusion injury (MI/R. However, the endogenous ligand responsible for TLR2 activation has not yet been detected. The objective of this study was to identify HMGB1 as an activator of TLR2 signalling during MI/R. C57BL/6 wild-type (WT or TLR2−/−-mice were injected with vehicle, HMGB1, or HMGB1 BoxA one hour before myocardial ischemia (30 min and reperfusion (24 hrs. Infarct size, cardiac troponin T, leukocyte infiltration, HMGB1 release, TLR4-, TLR9-, and RAGE-expression were quantified. HMGB1 plasma levels were measured in patients undergoing coronary artery bypass graft (CABG surgery. HMGB1 antagonist BoxA reduced cardiomyocyte necrosis during MI/R in WT mice, accompanied by reduced leukocyte infiltration. Injection of HMGB1 did, however, not increase infarct size in WT animals. In TLR2−/−-hearts, neither BoxA nor HMGB1 affected infarct size. No differences in RAGE and TLR9 expression could be detected, while TLR2−/−-mice display increased TLR4 and HMGB1 expression. Plasma levels of HMGB1 were increased MI/R in TLR2−/−-mice after CABG surgery in patients carrying a TLR2 polymorphism (Arg753Gln. We here provide evidence that absence of TLR2 signalling abrogates infarct-sparing effects of HMGB1 blockade.

  16. MicroRNAs regulate mitochondrial apoptotic pathway in myocardial ischemia-reperfusion-injury.

    Science.gov (United States)

    Makhdoumi, Pouran; Roohbakhsh, Ali; Karimi, Gholamreza

    2016-12-01

    MicroRNAs (miRNAs) are small non-coding RNAs that act as post-transcriptional gene regulators. They are involved in the pathogenesis of different disorders including heart diseases. MiRNAs contribute to ischemia/reperfusion injury (I/RI) by altering numerous key signaling elements. Together with alterations in the various potential signaling pathways, modification in miRNA expression has been suggested as a part of the response network following ischemia/reperfusion (I/R). In addition, cardiac mitochondrial homeostasis is closely associated with cardiac function and impairment of mitochondrial activity occurred after ischemia/reperfusion injury. MiRNAs play a key role in the regulation of mitochondrial apoptotic pathway and signaling proteins. In this review, we summarize the knowledge currently available regarding the molecular mechanisms of miRNA-regulated mitochondrial functions during ischemia/reperfusion injury. This regulation occurs in different stages of mitochondrial apoptosis pathway.

  17. Cardioprotective Effects of Genistin in Rat Myocardial Ischemia-Reperfusion Injury Studies by Regulation of P2X7/NF-κB Pathway

    Directory of Open Access Journals (Sweden)

    Meng Gu

    2016-01-01

    Full Text Available The present study aimed to assess the effects and mechanisms of genistin in the rat model of myocardial ischemia reperfusion injury. The rat hearts were exposed to the left anterior descending coronary artery (LAD ligation for 30 min followed by 1 h of reperfusion. In the rat of myocardial ischemia/reperfusion (MI/R, it was found that genistin pretreatment reduced myocardial infarct size, improved the heart rate, and decreased creatine kinase (CK and lactate dehydrogenase (LDH levels in coronary flow. This pretreatment also increased catalase (CAT, superoxide dismutase (SOD activities but decreased glutathione (GSH, malondialdehyde (MDA levels. Furthermore, we determined that genistin can ameliorate the impaired mitochondrial morphology and oxidation system; interleukin-6 (IL-6, interleukin-8 (IL-8, interleukin-10 (IL-10, and tumor necrosis factor-α (TNF-α levels were also recovered. Besides, related-proteins of nuclear factor kappa-B (NF-κB signal pathway activated by P2X7 were investigated to determine the molecular mechanism of genistin and their expressions were measured by western blot. These results presented here demonstrated that genistin enhanced the protective effect on the rats with myocardial ischemia reperfusion injury. Therefore, the cardioprotective effects of genistin may rely on its antioxidant and anti-inflammatory activities via suppression of P2X7/NF-κB pathways.

  18. Administration of zinc complex of acetylsalicylic acid after the onset of myocardial injury protects the heart by upregulation of antioxidant enzymes.

    Science.gov (United States)

    Korkmaz-Icöz, Sevil; Atmanli, Ayhan; Radovits, Tamás; Li, Shiliang; Hegedüs, Peter; Ruppert, Mihály; Brlecic, Paige; Yoshikawa, Yutaka; Yasui, Hiroyuki; Karck, Matthias; Szabó, Gábor

    2016-03-01

    We recently demonstrated that the pre-treatment of rats with zinc and acetylsalicylic acid complex in the form of bis(aspirinato)zinc(II) [Zn(ASA)2] is superior to acetylsalicylic acid in protecting the heart from acute myocardial ischemia. Herein, we hypothesized that Zn(ASA)2 treatment after the onset of an acute myocardial injury could protect the heart. The rats were treated with a vehicle or Zn(ASA)2 after an isoproterenol injection. Isoproterenol-induced cardiac damage [inflammatory infiltration into myocardial tissue, DNA-strand breakage evidenced by TUNEL-assay, increased 11-dehydro thromboxane (TX)B2-levels, elevated ST-segment, widened QRS complex and prolonged QT-interval] was prevented by the Zn(ASA)2 treatment. In isoproterenol-treated rats, load-independent left ventricular contractility parameters were significantly improved after Zn(ASA)2. Furthermore, Zn(ASA)2 significantly increased the myocardial mRNA-expression of superoxide dismutase-1, glutathione peroxidase-4 and decreased the level of Na(+)/K(+)/ATPase. Postconditioning with Zn(ASA)2 protects the heart from acute myocardial ischemia. Its mechanisms of action might involve inhibition of pro-inflammatory prostanoids and upregulation of antioxidant enzymes.

  19. The Protective Effect of MicroRNA-320 on Left Ventricular Remodeling after Myocardial Ischemia-Reperfusion Injury in the Rat Model

    Directory of Open Access Journals (Sweden)

    Chun-Li Song

    2014-09-01

    Full Text Available The primary objective of this study investigated the role of microRNA-320 (miR-320 on left ventricular remodeling in the rat model of myocardial ischemia-reperfusion (I/R injury, and we intended to explore the myocardial mechanism of miR-320-mediated myocardium protection. We collected 120 male Wistar rats (240–280 g in this study and then randomly divided them into three groups: (1 sham surgery group (sham group: n = 40; (2 ischemia-reperfusion model group (I/R group: n = 40; and (3 I/R model with antagomir-320 group (I/R + antagomir-320 group: n = 40. Value changes of heart function in transesophageal echocardiography were recorded at various time points (day 1, day 3, day 7, day 15 and day 30 after surgery in each group. Myocardial sections were stained with hematoxylin and eosin (H&E and examined with optical microscope. The degree of myocardial fibrosis was assessed by Sirius Red staining. Terminal dUTP nick end-labeling (TUNEL and qRT-PCR methods were used to measure the apoptosis rate and to determine the miR-320 expression levels in myocardial tissues. Transesophageal echocardiography showed that the values of left ventricular ejection fraction (LVEF, left ventricular fractional shortening (LVFS, left ventricular systolic pressure (LVSP and ±dp/dtmax in the I/R group were obviously lower than those in the sham group, while the left ventricular end-diastolic pressure (LVEDP value was higher than that in the sham group. The values of LVEF, LVFS, LVSP and ±dp/dtmax showed a gradual decrease in the I/R group, while the LVEDP value showed an up tendency along with the extension of reperfusion time. The H&E staining revealed that rat myocardial tissue in the I/R group presented extensive myocardial damage; for the I/R + antagomir-320 group, however, the degree of damage in myocardial cells was obviously better than that of the I/R group. The Sirius Red staining results showed that the degree of myocardial fibrosis in the I/R group was more

  20. Using the laws of thermodynamics to understand how matrix metalloproteinases coordinate the myocardial response to injury.

    Science.gov (United States)

    Iyer, Rugmani Padmanabhan; Jung, Mira; Lindsey, Merry L

    Following myocardial infarction (MI), the left ventricle (LV) undergoes a series of molecular, cellular, and functional alterations that are both part of the wound healing response to form a scar in the infarct region and the consequence of that response. Using the laws of thermodynamics as an analogy, we present here three laws for categorizing the post-MI LV remodeling process. The first law is that the LV will attempt to maintain equilibrium and compensate as a way to maximize function, the second law is that remodeling is progressive and unidirectional, and the third law is that the final goal is (ideally, but not always achievable) a stable, equilibrated scar. This comparison helps to define the boundaries of the system, whether it be the infarct zone, the LV, the heart, or the entire body. This review provides an overview for those not directly in the field and establishes a framework to help prioritize future research directions.

  1. Extended Irreversible Thermodynamics

    CERN Document Server

    Jou, David

    2010-01-01

    This is the 4th edition of the highly acclaimed monograph on Extended Irreversible Thermodynamics, a theory that goes beyond the classical theory of irreversible processes. In contrast to the classical approach, the basic variables describing the system are complemented by non-equilibrium quantities. The claims made for extended thermodynamics are confirmed by the kinetic theory of gases and statistical mechanics. The book covers a wide spectrum of applications, and also contains a thorough discussion of the foundations and the scope of the current theories on non-equilibrium thermodynamics. For this new edition, the authors critically revised existing material while taking into account the most recent developments in fast moving fields such as heat transport in micro- and nanosystems or fast solidification fronts in materials sciences. Several fundamental chapters have been revisited emphasizing physics and applications over mathematical derivations. Also, fundamental questions on the definition of non-equil...

  2. Stochastic dynamics and irreversibility

    CERN Document Server

    Tomé, Tânia

    2015-01-01

    This textbook presents an exposition of stochastic dynamics and irreversibility. It comprises the principles of probability theory and the stochastic dynamics in continuous spaces, described by Langevin and Fokker-Planck equations, and in discrete spaces, described by Markov chains and master equations. Special concern is given to the study of irreversibility, both in systems that evolve to equilibrium and in nonequilibrium stationary states. Attention is also given to the study of models displaying phase transitions and critical phenomema both in thermodynamic equilibrium and out of equilibrium. These models include the linear Glauber model, the Glauber-Ising model, lattice models with absorbing states such as the contact process and those used in population dynamic and spreading of epidemic, probabilistic cellular automata, reaction-diffusion processes, random sequential adsorption and dynamic percolation. A stochastic approach to chemical reaction is also presented.The textbook is intended for students of ...

  3. Irreversible quantum baker map.

    Science.gov (United States)

    Łoziński, Artur; Pakoński, Prot; Zyczkowski, Karol

    2002-12-01

    We propose a generalization of the model of classical baker map on the torus, in which the images of two parts of the phase space do overlap. This transformation is irreversible and cannot be quantized by means of a unitary Floquet operator. A corresponding quantum system is constructed as a completely positive map acting in the space of density matrices. We investigate spectral properties of this superoperator and their link with the increase of the entropy of initially pure states.

  4. Irreversible Quantum Baker Map

    CERN Document Server

    Lozinski, A; Zyczkowski, K; Lozinski, Artur; Pakonski, Prot; Zyczkowski, Karol

    2002-01-01

    We propose a generalization of the model of classical baker map on the torus, in which the images of two parts of the phase space do overlap. This transformation is irreversible and cannot be quantized by means of a unitary Floquet operator. A corresponding quantum system is constructed as a completely positive map acting in the space of density matrices. We investigate spectral properties of this super-operator and their link with the increase of the entropy of initially pure states.

  5. Progress in the research on diagnosis of neonatal myocardial injury%新生儿心肌损伤诊断的研究进展

    Institute of Scientific and Technical Information of China (English)

    薛丹

    2012-01-01

    近年来,随着新生儿特别是早产儿和危重新生儿成活率的提高,新生儿心肌损伤的发病率及病死率均有增加.新生儿心肌损伤的早期临床表现无明显特异性,容易被忽略,是围生期死亡的重要原因之一.文章就新生儿心肌损伤早期临床诊断指标的研究进展作一综述.%In recent years, with increased survival rate of neonates, especially premature and critically ill neoTiates, the morbidity and mortality of myocardial injuries were high. Myocardial injury in newboms has no obvious or specific clinical features at early stage, and is often undetected. It became one ofthe leading causes o of death in perinatal period. This article reviewed the progress in research on early clinical diagnosis of neonatal myocardial injury.

  6. Regulation of Na(+)-K(+)-ATPase effected high glucose-induced myocardial cell injury through c-Src dependent NADPH oxidase/ROS pathway.

    Science.gov (United States)

    Yan, Xiaofei; Xun, Meng; Dou, Xiaojuan; Wu, Litao; Han, Yan; Zheng, Jin

    2017-08-15

    Depressed Na(+)/K(+)-ATPase activity has long been reported to be involved in diabetic-related cardiomyocyte death and cardiac dysfunction. However, the nature of directly regulating Na(+)-K(+)-ATPase in diabetic-related myocardial diseases remains unknown. Hyperglycemia is believed as one of major factors responsible for diabetic-related myocardial apoptosis and dysfunction. In this study, whether inhibiting Na(+)-K(+)-ATPase by ouabain or activating Na(+)-K(+)-ATPase by DRm217 has functions on high glucose (HG) -induced myocardial injury was investigated. Here we found that addition of DRm217 or ouabain to HG-treated cells had opposite effects. DRm217 decreased but ouabain increased HG-induced cell injury and apoptosis. This was mediated by changing Na(+)-K(+)-ATPase activity and Na(+)-K(+)-ATPase cell surface expression. The inhibition of Na(+)-K(+)-ATPase endocytosis alleviated HG-induced ROS accumulation. Na(+)-K(+)-ATPase·c-Src dependent NADPH oxidase/ROS pathway was also involved in the effects of ouabain and DRm217 on HG-induced cell injury. These novel results may help us to understand the important role of the Na(+)-K(+)-ATPase in diabetic cardiovascular diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Left ventricular remodeling after experimental myocardial cryoinjury in rats.

    Science.gov (United States)

    Ciulla, Michele M; Paliotti, Roberta; Ferrero, Stefano; Braidotti, Paola; Esposito, Arturo; Gianelli, Umberto; Busca, Giuseppe; Cioffi, Ugo; Bulfamante, Gaetano; Magrini, Fabio

    2004-01-01

    The standard coronary ligation, the most studied model of experimental myocardial infarction in rats, is limited by high mortality and produces unpredictable areas of necrosis. To standardize the location and size of the infarct and to elucidate the mechanisms of myocardial remodeling and its progression to heart failure, we studied the functional, structural, and ultrastructural changes of myocardial infarction produced by experimental myocardial cryoinjury. The cryoinjury was successful in 24 (80%) of 30 male adult CD rats. A subepicardial infarct was documented on echocardiograms, with an average size of about 21%. Macroscopic examination reflected closely the stamp of the instrument used, without transition zones to viable myocardium. Histological examination, during the acute setting, revealed an extensive area of coagulation necrosis and hemorrhage in the subepicardium. An inflammatory infiltrate was evident since the 7th hour, whereas the reparative phase started within the first week, with proliferation of fibroblasts, endothelial cells, and myocytes. From the 7th day, deposition of collagen fibers was reported with a reparative scar completed at the 30th day. Ultrastructural study revealed vascular capillary damage and irreversible alterations of the myocytes in the acute setting and confirmed the histological findings of the later phases. The damage was associated with a progressive left ventricular (LV) remodeling, including thinning of the infarcted area, hypertrophy of the noninfarcted myocardium, and significant LV dilation. This process started from the 60th day and progressed over the subsequent 120 days period; at 180 days, a significant increase in LV filling pressure, indicative of heart failure, was found. In conclusion, myocardial cryodamage, although different in respect to ischemic damage, causes a standardized injury reproducing the cellular patterns of coagulation necrosis, early microvascular reperfusion, hemorrhage, inflammation

  8. Oxymatrine protects against sepsis-induced myocardial injury via inhibition of the TNF-α/p38-MAPK/caspase-3 signaling pathway.

    Science.gov (United States)

    Zhang, Minghao; Wang, Xiuyu; Bai, Bin; Zhang, Rui; Li, Yunhong; Wang, Yin

    2016-07-01

    Oxymatrine (OMT), which is a quinolizidine alkaloid extracted from the traditional Chinese herb Sophora flavescens Aiton, is often used to treat various inflammatory diseases. The present study aimed to investigate the protective effects of OMT against septic shock‑induced myocardial injury in rats, and to determine the underlying mechanisms. In the present study, cecal ligation and puncture (CLP) was applied to generate a rat model of sepsis. The rats were randomly divided into six groups (n=8/group): Sham operation (CON) group, OMT control group, CLP model group, and CLP + OMT (high dose, 52 mg/kg; medium dose, 26 mg/kg; low dose, 13 mg/kg) groups. Cardiac function and histological alterations were analyzed by light microscopy and electron microscopy. Myocardial cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The mRNA and protein expression levels were examined by reverse transcription-polymerase chain reaction and western blotting, respectively. Furthermore, the levels of tumor necrosis factor (TNF)‑α in the myocardial tissue were determined by radioimmunoassay. The results demonstrated that OMT exhibited anti‑inflammatory properties, improved myocardial contractility and compliance, and significantly decreased pathological injury to rat myocardial ultrastructure. In addition, OMT significantly decreased heart rate and left ventricular end diastolic pressure, and increased mean arterial pressure, left intraventricular pressure change rate, and left ventricular end systolic pressure in rats following septic shock. Treatment with OMT attenuated the mRNA expression of lipopolysaccharide binding protein, cluster of differentiation 14, nuclear factor (NF)‑κB (p65), TNF‑α, p38‑mitogen‑activated protein kinase (MAPK) and caspase‑3, and decreased the protein expression of NF‑κB (p65), phosphorylated (p) NF‑κB inhibitor‑α, p‑p38‑MAPK caspase‑3 and TNF‑α in septic myocardial

  9. The effects of Melissa officinalis (lemon balm) pretreatment on the resistance of the heart to myocardial injury.

    Science.gov (United States)

    Joukar, Siyavash; Asadipour, Haleh; Sheibani, Mohammad; Najafipour, Hamid; Dabiri, Shahriar

    2016-01-01

    The antihyperlipidemic, antiarrhythmic, neuroprotective and hepatoprotective effects of Melissa officinalis L. (Lamiaceae) have been reported. However, no study has examined its effects on the resistance of the heart to stressful conditions. The objective of this study is to evaluate the effects of aqueous extract of M. officinalis aerial parts on Wistar rat heart with/without cardiac injury. Animals were grouped as control, isoproterenol (ISO), M. officinalis without (M50, M100, and M200) and with isoproterenol (M50 + ISO, M100 + ISO, and M200 + ISO). The aqueous extract of M. officinalis was orally administered at dosages of 50, 100, and 200 mg/kg/d, respectively, for 7 consecutive days. On the 6th and 7th day, ISO, M50 + ISO, M100 + ISO, and M200 + ISO groups received 85 mg/kg of isoproterenol for myocardial injury induction. On day 8, hemodynamic parameters were recorded and samplings were done. The extract (50, 100, and 200 mg/kg) significantly reduced the heart rate (264 ± 5, 259 ± 5 and 281 ± 3 versus 377 ± 13 in control group, p < 0.01). Blood pressure was significantly decreased in M50 + ISO (75 ± 5) versus M50 (110 ± 6) and M100 + ISO (72 ± 6) versus M100 (105 ± 5 mmHg, p < 0.01). The malondialdehyde levels of the injured hearts were lower in M50 + ISO and M100 + ISO groups than in the ISO group (p < 0.05). Serum cardiac troponin I was higher in the M200 + ISO group (5.1 ± 1.7) than in the ISO group (2.7 ± 0.7 ng/ml, p < 0.05). The lower dose of extract, by improving the balance of the redox system and by reducing the heart rate, may increase the heart resistance to injury. However, the higher doses of extract may intensify the injury of ischemic heart.

  10. Implications of ventricular arrhythmia "bursts" with normal epicardial flow, myocardial blush, and ST-segment recovery in anterior ST-elevation myocardial infarction reperfusion: a biosignature of direct myocellular injury "downstream of downstream".

    Science.gov (United States)

    Majidi, Mohamed; Kosinski, Andrzej S; Al-Khatib, Sana M; Smolders, Lilian; Cristea, Ecaterina; Lansky, Alexandra J; Stone, Gregg W; Mehran, Roxana; Gibbons, Raymond J; Crijns, Harry J; Wellens, Hein J; Gorgels, Anton P; Krucoff, Mitchell W

    2015-02-01

    Establishing epicardial flow with percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) is necessary but not sufficient to ensure nutritive myocardial reperfusion. We evaluated whether adding myocardial blush grade (MBG) and quantitative reperfusion ventricular arrhythmia "bursts" (VABs) surrogates provide a more informative biosignature of optimal reperfusion in patients with Thrombolysis in Myocardial Infarction (TIMI) 3 flow and ST-segment recovery (STR). Anterior STEMI patients with final TIMI 3 flow had protocol-blinded analyses of simultaneous MBG, continuous 12-lead electrocardiogram (ECG) STR, Holter VABs, and day 5-14 SPECT imaging infarct size (IS) assessments. Over 20 million cardiac cycles from >4500 h of continuous ECG monitoring in subjects with STR were obtained. IS and clinical outcomes were examined in patients stratified by MBG and VABs. VABs occurred in 51% (79/154) of subjects. Microcirculation (MBG 2/3) was restored in 75% (115/154) of subjects, of whom 53% (61/115) had VABs. No VABs were observed in subjects without microvascular flow (MBG of 0). Of 115 patients with TIMI 3 flow, STR, and MBG 2/3, those with VABs had significantly larger IS (median: 23.0% vs 6.0%, p=0.001). Multivariable analysis identified reperfusion VABs as a factor significantly associated with larger IS (p=0.015). Despite restoration of normal epicardial flow, open microcirculation, and STR, concomitant VABs are associated with larger myocardial IS, possibly reflecting myocellular injury in reperfusion settings. Combining angiographic and ECG parameters of epicardial, microvascular, and cellular response to STEMI intervention provides a more predictive "biosignature" of optimal reperfusion than do single surrogate markers. © The European Society of Cardiology 2014.

  11. Myocardial Dysfunction in Acute Traumatic Brain Injury Relieved by Surgical Decompression

    OpenAIRE

    Vijay Krishnamoorthy; Deepak Sharma; Sumidtra Prathep; Vavilala, Monica S.

    2013-01-01

    Traumatic brain injury (TBI) is a major public health issue and is a leading cause of death in North America. After a primary TBI, secondary brain insults can predispose patients to a worse outcome. One of the earliest secondary insults encountered during the perioperative period is hypotension, which has been directly linked to both mortality and poor disposition after TBI. Despite this, it has been shown that hypotension commonly occurs during surgery for TBI. We present a case of intraoper...

  12. Protective effects of Araloside C against myocardial ischaemia/reperfusion injury: potential involvement of heat shock protein 90.

    Science.gov (United States)

    Wang, Min; Tian, Yu; Du, Yu-Yang; Sun, Gui-Bo; Xu, Xu-Dong; Jiang, Hai; Xu, Hui-Bo; Meng, Xiang-Bao; Zhang, Jing-Yi; Ding, Shi-Lan; Zhang, Miao-di; Yang, Ming-Hua; Sun, Xiao-Bo

    2017-09-01

    The present study was designed to investigate whether Araloside C, one of the major triterpenoid compounds isolated from Aralia elata known to be cardioprotective, can improve heart function following ischaemia/reperfusion (I/R) injury and elucidate its underlying mechanisms. We observed that Araloside C concentration-dependently improved cardiac function and depressed oxidative stress induced by I/R. Similar protection was confirmed in isolated cardiomyocytes characterized by maintaining Ca(2+) transients and cell shortening against I/R. Moreover, the potential targets of Araloside C were predicted using the DDI-CPI server and Discovery Studio software. Molecular docking analysis revealed that Araloside C could be stably docked into the ATP/ADP-binding domain of the heat shock protein 90 (Hsp90) protein via the formation of hydrogen bonds. The binding affinity of Hsp90 to Araloside C was detected using nanopore optical interferometry and yielded KD values of 29 μM. Araloside C also up-regulated the expression levels of Hsp90 and improved cell viability in hypoxia/reoxygenation-treated H9c2 cardiomyocytes, whereas the addition of 17-AAG, a pharmacologic inhibitor of Hsp90, attenuated Araloside C-induced cardioprotective effect. These findings reveal that Araloside C can efficiently attenuate myocardial I/R injury by reducing I/R-induced oxidative stress and [Ca(2+) ]i overload, which was possibly related to its binding to the Hsp90 protein. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  13. Intracoronary Poloxamer 188 Prevents Reperfusion Injury in a Porcine Model of ST-Segment Elevation Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Jason A. Bartos, MD, PhD

    2016-06-01

    Full Text Available Poloxamer 188 (P188 is a nonionic triblock copolymer believed to prevent cellular injury after ischemia and reperfusion. This study compared intracoronary (IC infusion of P188 immediately after reperfusion with delayed infusion through a peripheral intravenous catheter in a porcine model of ST-segment elevation myocardial infarction (STEMI. STEMI was induced in 55 pigs using 45 min of endovascular coronary artery occlusion. Pigs were then randomized to 4 groups: control, immediate IC P188, delayed peripheral P188, and polyethylene glycol infusion. Heart tissue was collected after 4 h of reperfusion. Assessment of mitochondrial function or infarct size was performed. Mitochondrial yield improved significantly with IC P188 treatment compared with control animals (0.25% vs. 0.13%, suggesting improved mitochondrial morphology and survival. Mitochondrial respiration and calcium retention were also significantly improved with immediate IC P188 compared with control animals (complex I respiratory control index: 7.4 vs. 3.7; calcium retention: 1,152 nmol vs. 386 nmol. This benefit was only observed with activation of complex I of the mitochondrial respiratory chain, suggesting a specific effect from ischemia and reperfusion on this complex. Infarct size and serum troponin I were significantly reduced by immediate IC P188 infusion (infarct size: 13.9% vs. 41.1%; troponin I: 19.2 μg/l vs. 77.4 μg/l. Delayed P188 and polyethylene glycol infusion did not provide a significant benefit. These results demonstrate that intracoronary infusion of P188 immediately upon reperfusion significantly reduces cellular and mitochondrial injury after ischemia and reperfusion in this clinically relevant porcine model of STEMI. The timing and route of delivery were critical to achieve the benefit.

  14. Ischemia reperfusion injury, ischemic conditioning and diabetes mellitus.

    Science.gov (United States)

    Lejay, Anne; Fang, Fei; John, Rohan; Van, Julie A D; Barr, Meredith; Thaveau, Fabien; Chakfe, Nabil; Geny, Bernard; Scholey, James W

    2016-02-01

    Ischemia/reperfusion, which is characterized by deficient oxygen supply and subsequent restoration of blood flow, can cause irreversible damages to tissue. Mechanisms contributing to the pathogenesis of ischemia reperfusion injury are complex, multifactorial and highly integrated. Extensive research has focused on increasing organ tolerance to ischemia reperfusion injury, especially through the use of ischemic conditioning strategies. Of morbidities that potentially compromise the protective mechanisms of the heart, diabetes mellitus appears primarily important to study. Diabetes mellitus increases myocardial susceptibility to ischemia reperfusion injury and also modifies myocardial responses to ischemic conditioning strategies by disruption of intracellular signaling responsible for enhancement of resistance to cell death. The purpose of this review is twofold: first, to summarize mechanisms underlying ischemia reperfusion injury and the signal transduction pathways underlying ischemic conditioning cardioprotection; and second, to focus on diabetes mellitus and mechanisms that may be responsible for the lack of effect of ischemic conditioning strategies in diabetes.

  15. Time course characterization of serum cardiac troponins, heart fatty acid-binding protein, and morphologic findings with isoproterenol-induced myocardial injury in the rat.

    Science.gov (United States)

    Clements, Peter; Brady, Sally; York, Malcolm; Berridge, Brian; Mikaelian, Igor; Nicklaus, Rosemary; Gandhi, Mitul; Roman, Ian; Stamp, Clare; Davies, Dai; McGill, Paul; Williams, Thomas; Pettit, Syril; Walker, Dana; Turton, John

    2010-08-01

    We investigated the kinetics of circulating biomarker elevation, specifically correlated with morphology in acute myocardial injury. Male Hanover Wistar rats underwent biomarker and morphologic cardiac evaluation at 0.5 to seventy-two hours after a single subcutaneous isoproterenol administration (100 or 4000 microg/kg). Dose-dependent elevations of serum cardiac troponins I and T (cTnI, cTnT), and heart fatty acid-binding protein (H-FABP) occurred from 0.5 hour, peaked at two to three hours, and declined to baseline by twelve hours (H-FABP) or forty-eight to seventy-two hours (Serum cTns). They were more sensitive in detecting cardiomyocyte damage than other serum biomarkers. The Access 2 platform, an automated chemiluminescence analyzer (Beckman Coulter), showed the greatest cTnI fold-changes and low range sensitivity. Myocardial injury was detected morphologically from 0.5 hour, correlating well with loss of cTnI immunoreactivity and serum biomarker elevation at early time points. Ultrastructurally, there was no evidence of cardiomyocyte death at 0.5 hour. After three hours, a clear temporal disconnect occurred: lesion scores increased with declining cTnI, cTnT, and H-FABP values. Serum cTns are sensitive and specific markers for detecting acute/active cardiomyocyte injury in this rat model. Heart fatty acid-binding protein is a good early marker but is less sensitive and nonspecific. Release of these biomarkers begins early in myocardial injury, prior to necrosis. Assessment of cTn merits increased consideration for routine screening of acute/ongoing cardiomyocyte injury in rat toxicity studies.

  16. Urine and serum microRNA-1 as novel biomarkers for myocardial injury in open-heart surgeries with cardiopulmonary bypass.

    Science.gov (United States)

    Zhou, Xian; Mao, Anqiong; Wang, Xiaobin; Duan, Xiaoxia; Yao, Yi; Zhang, Chunxiang

    2013-01-01

    MicroRNA-1 (miR-1) is a cardio-specific/enriched microRNA. Our recent studies have revealed that serum and urine miR-1 could be a novel sensitive biomarker for acute myocardial infarction. Open-heart surgeries with cardiopulmonary bypass (CPB) are often accompanied with surgery injury and CPB-associated injury on the hearts. However, the association of miR-1 and these intra-operative and post-operative cardiac injures is unknown. The objective of this study was to test the hypothesis that urine and serum miR-1 might be a novel biomarker for myocardial injuries in open-heart surgeries with CPB. Serum and urine miR-1 levels in 20 patients with elective mitral valve surgery were measured at pre-surgery, pre-CPB, 60 min post-CBP, and 24h post-CBP. Serum cardiac troponin-I (cTnI) was used as a positive control biomarker for cardiac injury. Compared with these in pre-operative and pre-CPB groups, the levels of miR-1 in serum and urine from patients after open-heart surgeries and CPB were significant increased at all observed time points. A similar pattern of serum cTnI levels and their strong positive correlation with miR-1 levels were identified in these patients. The results suggest that serum and urine miR-1 may be a novel sensitive biomarker for myocardial injury in open-heart surgeries with CPB.

  17. Efficacy of Multidetector Computed Tomography to Predict Periprocedural Myocardial Injury After Percutaneous Coronary Intervention for Chronic Total Occlusion.

    Science.gov (United States)

    Usui, Eisuke; Lee, Tetsumin; Murai, Tadashi; Kanaji, Yoshihisa; Matsuda, Junji; Araki, Makoto; Yonetsu, Taishi; Yamakami, Yosuke; Kimura, Shigeki; Kakuta, Tsunekazu

    2017-02-07

    Specific signatures of culprit lesions detected on multidetector computed tomography (MDCT) were identified as predictors of periprocedural myocardial injury (PMI) after percutaneous coronary intervention (PCI) in patients with stable angina; PMI has been shown to be associated with a worse prognosis. We investigated the association between preprocedural culprit lesion characteristics, assessed by MDCT, and PMI after PCI for chronic total occlusion (CTO). From three medical centers, 81 patients who underwent pre-PCI MDCT and CTO PCI, and systematic cardiac troponin (cTn) sampling before and after PCI, were included. Patients were divided into two groups according to the presence or absence of post-PCI cTn elevation. Patient characteristics, MDCT findings, and procedural variables were compared between the two groups. Procedure success was observed in 65 patients (80.2%) and was not associated with PMI. The incidence of PMI was higher in patients treated with the retrograde versus the antegrade approach. On MDCT, lesion length and the presence of the napkin-ring sign were significantly associated with PMI. Multivariate analysis revealed that the lesion length (odds ratio [OR]: 1.04; 95% confidence interval [CI]: 1.01-1.08; P PMI. PMI is not uncommon in patients undergoing elective CTO PCI, regardless of procedure success or failure. Pre-PCI MDCT may help identify patients at high risk for PMI after CTO PCI.

  18. Incidence and Mortality of Acute Kidney Injury after Myocardial Infarction: A Comparison between KDIGO and RIFLE Criteria

    Science.gov (United States)

    Rodrigues, Fernando B.; Bruetto, Rosana G.; Torres, Ulysses S.; Otaviano, Ana P.

    2013-01-01

    Background Acute kidney injury (AKI) increases the risk of death after acute myocardial infarction (AMI). Recently, a new AKI definition was proposed by the Kidney Disease Improving Global Outcomes (KDIGO) organization. The aim of the current study was to compare the incidence and the early and late mortality of AKI diagnosed by RIFLE and KDIGO criteria in the first 7 days of hospitalization due to an AMI. Methods and Results In total, 1,050 AMI patients were prospectively studied. AKI defined by RIFLE and KDIGO occurred in 14.8% and 36.6% of patients, respectively. By applying multivariate Cox analysis, AKI was associated with an increased adjusted hazard ratio (AHR) for 30-day death of 3.51 (95% confidence interval [CI] 2.35–5.25, pRIFLE and 3.99 (CI 2.59–6.15, pRIFLE and 2.43 (CI 1.62–3.62, pRIFLE but as AKI by KDIGO criteria had also an increased AHR for death of 2.55 (1.52–4.28) at 30 days and 2.28 (CI 1.46–3.54) at 1 year (pRIFLE among AMI patients. Patients diagnosed as AKI by KDIGO but not RIFLE criteria had a significantly higher early and late mortality. In this study KDIGO criteria were more suitable for AKI diagnosis in AMI patients than RIFLE criteria. PMID:23894572

  19. Effect of Ligustrazine and Shenmai Injection on ATPase and free radical metabolism in the aged rats with myocardial injury after brain ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To study the protecitve mechanism of Ligustrazine (LT), Shenmai Parenteral Injection (SPI), combination of Ligustrazine and Shenmai Parenteral Injection (LSP) to myocardial injury after brain ischemia-reperfusion in aged rats from the change in ATPase and free radical in order to provide theoretical basic for prevention and cure of cerebral infarction. METHODS: Aged rats (more than 20 months) were divided into model group, control group, Nimotop group, LT group, SPI group and LSP group. We measured the following items in aged rats with 60 min of reperfusion after 30 min of brain ischemia: the content of MDA, the activities of superoxide dismutase (SOD), lactic dehydrrogenase (LDH), creatine phosphokinase (CPK), ATPase. RESUTLS: The CPK and LDH activities in the model rats increased obviously. The serum CPK activity in the LSP group, the LT group, nimotop group was lower than those in the model group obviously. The serum LDH activities in LT group and SPI group were obviously lower compared with those in the model group. The activity of Na+-K+-ATPase and Ca2+-ATPase in model group was decreased. Contrast to the model group, the activity of Na+-K+-ATPase in LSP group, Nimotop group, LT group and the activities of Ca2+-ATPase in the LSP group were higher. The serum MDA/SOD ratio was larger than that in the control group. The decrease in myocardial SOD activity and the increase in the MDA level, MDA/SOD ratio in the model group showed significant difference compared with that in the control. The MDA level in the LSP group was lower than that in the model group. The increase in myocardial SOD activity and decrease in MDA, MDA/SOD ratio were obvious in the LSP group compared with the model group. CONCLUSION: The myocardial injury after brain ischemia-reperfusion in aged rats was related to the decrease in the activity of Na+-K+-ATPase and injury of free radical. LT, SPI, LSP and Nimotop could prevent this inury. Nimotop and LT could enhanced the

  20. JNK/PI3K/Akt signaling pathway is involved in myocardial ischemia/reperfusion injury in diabetic rats: effects of salvianolic acid A intervention.

    Science.gov (United States)

    Chen, Qiuping; Xu, Tongda; Li, Dongye; Pan, Defeng; Wu, Pei; Luo, Yuanyuan; Ma, Yanfeng; Liu, Yang

    2016-01-01

    Recent studies have demonstrated that diabetes impairs the phosphatidylinositol 3-kinase/Akt (PI3K/Akt) pathway, while insulin resistance syndrome has been associated with alterations of this pathway in diabetic rats after ischemia/reperfusion (I/R), and activation of C-jun N-terminal kinase (JNK) is involved. The present study was designed to investigate whether inhibiting JNK activity would partially restore the PI3K/Akt signaling pathway and protect against myocardial I/R injury in diabetic rats, and to explore the effect of intervention with salvianolic acid A (Sal A). The inhibitor of JNK (SP600125) and Sal A were used in type 2 diabetic (T2D) rats, outcome measures included heart hemodynamic data, myocardial infarct size, the release of lactate dehydrogenase (LDH), SERCA2a activity, cardiomyocyte apotosis, expression levels of Bcl-2, Bax and cleaved caspase-3, and the phosphorylation status of Akt and JNK. The p-Akt levels were increased after myocardial I/R in non-diabetic rats, while there was no change in diabetic rats. Pretreatment with the SP600125 and Sal A decreased the p-JNK levels and increased the p-Akt levels in diabetic rats with I/R, and heart hemodynamic data improved, infarct size and LDH release decreased, SERCA2a activity increased, Bax and cleaved caspase-3 expression levels decreased, and the expression of Bcl-2 and the Bcl-2/Bax ratio increased. Our results suggest that the JNK/PI3K/Akt signaling pathway is involved in myocardial I/R injury in diabetic rats and Sal A exerts an anti-apoptotic effect and improves cardiac function following I/R injury through the JNK/PI3K/Akt signaling pathway in this model.

  1. Low-Level Tragus Stimulation for the Treatment of Ischemia and Reperfusion Injury in Patients With ST-Segment Elevation Myocardial Infarction: A Proof-of-Concept Study.

    Science.gov (United States)

    Yu, Lilei; Huang, Bing; Po, Sunny S; Tan, Tuantuan; Wang, Menglong; Zhou, Liping; Meng, Guannan; Yuan, Shenxu; Zhou, Xiaoya; Li, Xuefei; Wang, Zhuo; Wang, Songyun; Jiang, Hong

    2017-08-14

    The aim of this study was to investigate whether low-level tragus stimulation (LL-TS) treatment could reduce myocardial ischemia-reperfusion injury in patients with ST-segment elevation myocardial infarction (STEMI). The authors' previous studies suggested that LL-TS could reduce the size of myocardial injury induced by ischemia. Patients who presented with STEMI within 12 h of symptom onset, treated with primary percutaneous coronary intervention, were randomized to the LL-TS group (n = 47) or the control group (with sham stimulation [n = 48]). LL-TS, 50% lower than the electric current that slowed the sinus rate, was delivered to the right tragus once the patients arrived in the catheterization room and lasted for 2 h after balloon dilatation (reperfusion). All patients were followed for 7 days. The occurrence of reperfusion-related arrhythmia, blood levels of creatine kinase-MB, myoglobin, N-terminal pro-B-type natriuretic peptide and inflammatory markers, and echocardiographic characteristics were evaluated. The incidence of reperfusion-related ventricular arrhythmia during the first 24 h was significantly attenuated by LL-TS. In addition, the area under the curve for creatine kinase-MB and myoglobin over 72 h was smaller in the LL-TS group than the control group. Furthermore, blood levels of inflammatory markers were decreased by LL-TS. Cardiac function, as demonstrated by the level of N-terminal pro-B-type natriuretic peptide, the left ventricular ejection fraction, and the wall motion index, was markedly improved by LL-TS. LL-TS reduces myocardial ischemia-reperfusion injury in patients with STEMI. This proof-of-concept study raises the possibility that this noninvasive strategy may be used to treat patients with STEMI undergoing primary percutaneous coronary intervention. Copyright © 2017. Published by Elsevier Inc.

  2. The effect of oxidative stress in myocardial cell injury in mice exposed to chronic intermittent hypoxia

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-nan; ZHANG Jie-xin; LIU gan; QIU Yan; YANG Di; YIN Guo-yong; ZHANG Xi-long

    2010-01-01

    Background Obstructive sleep apnea syndrome (OSAS) is an important risk factor for cardiovascular diseases. Chronic intermittent hypoxia (CIH) is considered to be one of the most important causes of cardiovascular diseases in OSA patients. This repeated hypoxia and reoxygenation cycle is similar to hypoxia-reperfusion injury, which initiates oxidative stress. In this study, we observed cardiocytes injury induced by CIH and the effect of N-acetylcysteine (NAC). Methods Thirty ICR mice were randomly assigned to 3 groups: control, CIH and NAC (CIH+NAC) groups. Malondialdehyde (MDA) and superoxide dismutase (SOD) of cardiocyte homogenates were measured. Serum lipids were measured by an instrument method. Serum cardiac troponin I (cTnl) was detected by enzyme-linked immunosorbent assays (ELISA). Myocardium pathological sections were observed.Results (1) The SOD activity and MDA concentration of cardiocyte homogenates in the CIH group were significantly higher than in other groups (P <0.005). The MDA concentration of the NAC group was lower than that of the control group (P <0.01). (2) The serum cTnl concentration of the CIH and NAC groups was significantly higher than that of the control group (P<0.01). (3) Serum triglyceride levels in the NAC group were lower than in the other groups (P<0.01), while there were no significant differences in low density lipoprotein and high density lipoprotein among the three groups. (4) The degeneration of myocardium, transverse striation blurred, and fabric effusion were observed in tissue sections in the CIH and NAC groups. However, normal tissue was found in the control group.Conclusion The oxidative stress induced by CIH can injure cardiocytes and the injury effect can be partially inhibited by NAC.

  3. Irreversibility time scale.

    Science.gov (United States)

    Gallavotti, G

    2006-06-01

    Entropy creation rate is introduced for a system interacting with thermostats (i.e., for a system subject to internal conservative forces interacting with "external" thermostats via conservative forces) and a fluctuation theorem for it is proved. As an application, a time scale is introduced, to be interpreted as the time over which irreversibility becomes manifest in a process leading from an initial to a final stationary state of a mechanical system in a general nonequilibrium context. The time scale is evaluated in a few examples, including the classical Joule-Thompson process (gas expansion in a vacuum).

  4. Melatonin ameliorates myocardial ischemia/reperfusion injury in type 1 diabetic rats by preserving mitochondrial function: role of AMPK-PGC-1α-SIRT3 signaling

    Science.gov (United States)

    Yu, Liming; Gong, Bing; Duan, Weixun; Fan, Chongxi; Zhang, Jian; Li, Zhi; Xue, Xiaodong; Xu, Yinli; Meng, Dandan; Li, Buying; Zhang, Meng; Bin Zhang; Jin, Zhenxiao; Yu, Shiqiang; Yang, Yang; Wang, Huishan

    2017-01-01

    Enhancing mitochondrial biogenesis and reducing mitochondrial oxidative stress have emerged as crucial therapeutic strategies to ameliorate diabetic myocardial ischemia/reperfusion (MI/R) injury. Melatonin has been reported to be a safe and potent cardioprotective agent. However, its role on mitochondrial biogenesis or reactive oxygen species (ROS) production in type 1 diabetic myocardium and the underlying mechanisms remain unknown. We hypothesize that melatonin ameliorates MI/R injury in type 1 diabetic rats by preserving mitochondrial function via AMPK-PGC-1α-SIRT3 signaling pathway. Both our in vivo and in vitro data showed that melatonin reduced MI/R injury by improving cardiac function, enhancing mitochondrial SOD activity, ATP production and oxidative phosphorylation complex (II, III and IV), reducing myocardial apoptosis and mitochondrial MDA, H2O2 generation. Importantly, melatonin also activated AMPK-PGC-1α-SIRT3 signaling and increased SOD2, NRF1 and TFAM expressions. However, these effects were abolished by Compound C (a specific AMPK signaling blocker) administration. Additionally, our cellular experiment showed that SIRT3 siRNA inhibited the cytoprotective effect of melatonin without affecting p-AMPK/AMPK ratio and PGC-1α expression. Taken together, we concluded that melatonin preserves mitochondrial function by reducing mitochondrial oxidative stress and enhancing its biogenesis, thus ameliorating MI/R injury in type 1 diabetic state. AMPK-PGC1α-SIRT3 axis plays an essential role in this process. PMID:28120943

  5. Cardioprotection by combination of three compounds from ShengMai preparations in mice with myocardial ischemia/reperfusion injury through AMPK activation-mediated mitochondrial fission

    Science.gov (United States)

    Li, Fang; Fan, Xiaoxue; Zhang, Yu; Pang, Lizhi; Ma, Xiaonan; Song, Meijia; Kou, Junping; Yu, Boyang

    2016-01-01

    GRS is a drug combination of three active components including ginsenoside Rb1, ruscogenin and schisandrin. It derived from the well-known TCM formula ShengMai preparations, a widely used traditional Chinese medicine for the treatment of cardiovascular diseases in clinic. The present study explores the cardioprotective effects of GRS on myocardial ischemia/reperfusion (MI/R) injury compared with ShengMai preparations and investigates the underlying mechanisms. GRS treatment significantly attenuated MI/R injury and exhibited similar efficacy as Shengmai preparations, as evidenced by decreased myocardium infarct size, ameliorated histological features, the decrease of LDH production and improved cardiac function, and also produced a significant decrease of apoptotic index. Mechanistically, GRS alleviated myocardial apoptosis by inhibiting the mitochondrial mediated apoptosis pathway as reflected by inhibition of caspase-3 activity, normalization of Bcl-2/Bax levels and improved mitochondrial function. Moreover, GRS prevented cardiomyocytes mitochondrial fission and upregulated AMPKα phosphorylation. Interestingly, AMPK activation prevented hypoxia and reoxygenation induced mitochondrial fission in cardiomyocytes and GRS actions were significantly attenuated by knockdown of AMPKα. Collectively, these data show that GRS is effective in mitigating MI/R injury by suppressing mitochondrial mediated apoptosis and modulating AMPK activation-mediated mitochondrial fission, thereby providing a rationale for future clinical applications and potential therapeutic strategy for MI/R injury. PMID:27869201

  6. Redox activation of Ref-1 potentiates cell survival following myocardial ischemia reperfusion injury.

    Science.gov (United States)

    Gurusamy, Narasimman; Malik, Gautam; Gorbunov, Nikolai V; Das, Dipak K

    2007-08-01

    A recent study showed that cardiac adaptation could potentiate translocation of thioredoxin-1 (Trx-1) into the nucleus, which then interacted with Ref-1, resulting in a survival signal. Here, we present evidence that such adaptation also causes nuclear translocation of Ref-1, which is almost completely inhibited when the hearts were pretreated with antisense Ref-1 that also abolished the cardioprotective adaptive response. Significant amounts of NFkappaB and Nrf2 were found to be associated with Ref-1 when the nuclear extract obtained from the left ventricle was immunoprecipitated with Ref-1. Such Ref-1-NFkappaB and Ref-1-Nrf2 interactions were significantly inhibited with antisense Ref-1. However, immunoprecipitation of nuclear extract with NFkappaB showed that the association of Trx-1 with NFkappaB is increased in the adapted heart, which was again significantly blocked by antisense Ref-1. Nrf2 was also associated with NFkappaB; however, such association appeared to be independent of Ref-1. In contrast, myocardial adaptation to ischemia inhibited the ischemia reperfusion-induced loss of Nrf2 from the nucleus, which was inhibited by antisense Ref-1. The nuclear translocation and activation of Ref-1 appeared to generate a survival signal as evidenced by the increased phosphorylation of Akt that was inhibited with antisense Ref-1. Finally, confocal microscopy confirmed the results of immunoblotting, clearly showing the nuclear translocation of Ref-1 and nuclear 3D colocalization of Ref-1 with NFkappaB in the adapted heart and its inhibition with antisense Ref-1. Our results show that PC potentiates a survival signal through the phosphorylation of Akt by causing nuclear translocation and activation of Ref-1, where significant interaction among NFkappaB and Ref-1, Trx-1, and Nrf2 appears to regulate Ref-1-induced survival signal.

  7. Effect of one-cycle remote ischemic preconditioning to reduce myocardial injury during percutaneous coronary intervention.

    Science.gov (United States)

    Zografos, Theodoros A; Katritsis, George D; Tsiafoutis, Ioannis; Bourboulis, Nikolaos; Katsivas, Apostolos; Katritsis, Demosthenes G

    2014-06-15

    Up to 1/3 of percutaneous coronary interventions (PCIs) are complicated by troponin release. Remote ischemic preconditioning (IPC) confers effective cardioprotection; however, a 30-minute remote IPC protocol may be difficult to implement during ad hoc PCI. This study was performed to assess the ability of a brief remote IPC protocol to attenuate cardiac troponin I (cTnI) release after ad hoc PCI. Ninety-four patients undergoing ad hoc PCI for stable coronary artery disease, with undetectable preprocedural cTnI, were recruited and randomized to receive remote IPC (induced by one 5-minute inflation of a blood pressure cuff to 200 mm Hg around the upper arm) or control after the decision for PCI was made. The primary outcome was the difference between cTnI levels 24 hours after PCI and cTnI levels before coronary angiography (ΔcTnI). ΔcTnI in the remote IPC group was significantly lower compared with the control group (0.04 ng/ml [interquartile range 0.01 to 0.14] vs 0.19 ng/ml [interquartile range 0.18 to 0.59], p <0.001). The incidence of PCI-related myocardial infarction (MI) was greater in the control group (42.6% vs 19.1%, p = 0.014). In multivariate analysis, remote IPC was independently associated with ΔcTnI and PCI-related MI. In conclusion, our results suggest that even 1 cycle of remote IPC immediately before ad hoc PCI attenuates periprocedural cTnI release and reduces the incidence of type 4a MI.

  8. Inhibition of myocardial ischemia/reperfusion injury by exosomes secreted from mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Heng; XIANG Meng; MENG Dan; SUN Ning; CHEN Si-feng

    2016-01-01

    Exosomes secreted by mesenchymal stem cells have shown great therapeutic potential in regenerative medicine .In this study, we performed meta-analysis to assess the clinical effectiveness of using exosomes in ischemia /reperfusion injury based on the reports pub-lished between January 2000 and September 2015 and indexed in the PubMed and Web of Science databases .The effect of exosomes on heart function was evaluated according to the following parameters:the area at risk as a percentage of the left ventricle , infarct size as a percentage of the area at risk , infarct size as a percentage of the left ventricle , left ventricular ejection fraction , left ventricular frac-tion shortening , end-diastolic volume , and end-systolic volume .Our analysis indicated that the currently available evidence confirmed the therapeutic potential of mesenchymal stem cell-secreted exosomes in the improvement of heart function .However , further mechanis-tic studies, therapeutic safety and clinical trials are required for optimization and validation of this approach to cardiac regeneration after ischemia/reperfusion injury .

  9. Determinants and Prognostic Significance of Periprocedural Myocardial Injury in Patients With Successful Percutaneous Chronic Total Occlusion Interventions.

    Science.gov (United States)

    Lee, Seung-Whan; Lee, Pil H; Kang, Se H; Choi, Hanul; Chang, Mineok; Roh, Jae-Hyung; Yoon, Sung-Han; Ahn, Jung-Min; Park, Duk-Woo; Kang, Soo-Jin; Kim, Young-Hak; Lee, Cheol Whan; Park, Seong-Wook; Park, Seung-Jung

    2016-11-14

    This study sought to evaluate the determinants and prognostic implications of periprocedural myocardial injury (PMI) in successful percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs). There are limited studies addressing the risk factors and clinical implication of PMI in patients undergoing CTO-PCI. We examined 1,058 consecutive CTO patients who underwent successful drug-eluting stent implantation and serial measurements of creatine kinase-myocardial band (CK-MB) values between March 2003 and August 2014. PMI was defined as elevations of CK-MB >3 times the upper reference limit (URL). PMI occurred in 121 patients (11.4%). Multivariable analysis revealed that the presence of renal failure (odds ratio [OR]: 4.25; 95% confidence interval [CI]: 1.59 to 11.35; p = 0.004), attempted retrograde approach (OR: 2.27; 95% CI: 1.34 to 3.84; p = 0.002), concomitant non-target lesion intervention (OR: 1.74; 95% CI: 1.17 to 2.59; p = 0.006), and stent number (OR: 1.38; 95% CI: 1.08 to 1.77; p = 0.011) were predictors associated with PMI. During a median follow-up of 4.4 years, PMI was associated with an increased risk of mortality (adjusted hazard ratio: 1.86; 95% CI: 1.09 to 3.17; p = 0.02). These findings were also consistent when higher CK-MB cutoff was used to define PMI. Although there was a trend toward higher all-cause mortality with increasing peak CK-MB levels, in multivariable analyses, this association was statistically significant only for peak CK-MB levels of >10 times the URL. PMI was associated with an increased risk of long-term mortality after successful CTO-PCI. Patients with renal insufficiency, those who require more stents, multiple lesion treatment, and retrograde approach have a higher likelihood of having PMI. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Regulation of signal transducer and activator of transcription 3 and apoptotic pathways by betaine attenuates isoproterenol-induced acute myocardial injury in rats.

    Science.gov (United States)

    Zheng, P; Liu, J; Mai, S; Yuan, Y; Wang, Y; Dai, G

    2015-05-01

    The present study was designed to investigate the cardioprotective effects of betaine on acute myocardial ischemia induced experimentally in rats focusing on regulation of signal transducer and activator of transcription 3 (STAT3) and apoptotic pathways as the potential mechanism underlying the drug effect. Male Sprague Dawley rats were treated with betaine (100, 200, and 400 mg/kg) orally for 40 days. Acute myocardial ischemic injury was induced in rats by subcutaneous injection of isoproterenol (85 mg/kg), for two consecutive days. Serum cardiac marker enzyme, histopathological variables and expression of protein levels were analyzed. Oral administration of betaine (200 and 400 mg/kg) significantly reduced the level of cardiac marker enzyme in the serum and prevented left ventricular remodeling. Western blot analysis showed that isoproterenol-induced phosphorylation of STAT3 was maintained or further enhanced by betaine treatment in myocardium. Furthermore, betaine (200 and 400 mg/kg) treatment increased the ventricular expression of Bcl-2 and reduced the level of Bax, therefore causing a significant increase in the ratio of Bcl-2/Bax. The protective role of betaine on myocardial damage was further confirmed by histopathological examination. In summary, our results showed that betaine pretreatment attenuated isoproterenol-induced acute myocardial ischemia via the regulation of STAT3 and apoptotic pathways.

  11. Endoplasmic Reticulum Is Involved in Myocardial Injury in a Miniature Swine Model of Coronary Artery Stenosis Exposed to Acceleration-Associated Stress

    Science.gov (United States)

    Zhang, Haitao; Chai, Meng; Liu, Chaozhong; Sun, Jinjin; Huang, Congchun; Yu, Xinya; Tian, Yi; Luo, Huilan

    2015-01-01

    This study aimed to investigate the effects of myocardial injury in a minimally-invasive miniature swine model with different levels of coronary artery stenosis (CAS) and exposed to maximal tolerated +Gz. Proximal left anterior descending branch was ligated in 20 swine. Five swine underwent a sham operation. A trapezoid acceleration curve was used for +Gz stress. Pathological changes of myocardial tissue were detected by H&E staining. Apoptotic cardiomyocytes were detected by TUNEL. GRP78 and CHOP were investigated by immunohistochemistry and western blot. CAS models were successful in 18 animals.Compared with the sham-operated group (+8.00±0.71 Gz), the maximal tolerated +Gz values of the moderate stenosis (+6.00±0.89 Gz, Pstenosis groups (+5.20±0.84 Gz, Pstenosis group (60.50±9.35%, Pstenosis groups (0.35±0.04), while expression was high in the moderate (0.72±0.04, Pstenosis groups (0.65±0.07, Pstenosis groups. These results indicated that Under maximum exposure to +Gz stress, different levels of CAS led to different levels of myocardial injury. Endoplasmic reticulum response is involved in the apoptosis of cardiomyocytes after +Gz stress. PMID:26167928

  12. Inhibition of KV7 channels protects against myocardial ischemia and reperfusion injury

    DEFF Research Database (Denmark)

    Hedegaard, Elise Røge; Johnsen, Jacob; Povlsen, Jonas Agerlund;

    2015-01-01

    Aims: KV7 channel are activated by ischemia and mediate hypoxic vasodilatation. We investigated the effect of KV7 channel modulation on cardiac ischemia and reperfusion (IR) injury and the interaction with cardioprotection by ischemic preconditioning (IPC). Methods and Results: We investigated......-flow, global ischemia and reperfusion with and without IPC. Infarct size (IS) was quantified by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Hemodynamics were measured using a catheter inserted in the left ventricle. Functional studies on isolated coronary arteries were performed in a wire myograph. KV7.......1, KV7.4 and KV7.5 were expressed in rat coronary arteries and all KV7 subtypes (KV7.1-5) in the left and right ventricles of the heart. KV7 channel blockade by XE991 and linopirdine reduced infarct size additive to infarct reduction by IPC. Flupirtine abolished infarct size reduction by IPC...

  13. Protection against myocardial ischemia-reperfusion injury at onset of type 2 diabetes in Zucker diabetic fatty rats is associated with altered glucose oxidation.

    Directory of Open Access Journals (Sweden)

    Jonas Agerlund Povlsen

    Full Text Available BACKGROUND: Inhibition of glucose oxidation during initial reperfusion confers protection against ischemia-reperfusion (IR injury in the heart. Mitochondrial metabolism is altered with progression of type 2 diabetes (T2DM. We hypothesized that the metabolic alterations present at onset of T2DM induce cardioprotection by metabolic shutdown during IR, and that chronic alterations seen in late T2DM cause increased IR injury. METHODS: Isolated perfused hearts from 6 (prediabetic, 12 (onset of T2DM and 24 (late T2DM weeks old male Zucker diabetic fatty rats (ZDF and their age-matched heterozygote controls were subjected to 40 min ischemia/120 min reperfusion. IR injury was assessed by TTC-staining. Myocardial glucose metabolism was evaluated by glucose tracer kinetics (glucose uptake-, glycolysis- and glucose oxidation rates, myocardial microdialysis (metabolomics and tissue glycogen measurements. RESULTS: T2DM altered the development in sensitivity towards IR injury compared to controls. At late diabetes ZDF hearts suffered increased damage, while injury was decreased at onset of T2DM. Coincident with cardioprotection, oxidation of exogenous glucose was decreased during the initial and normalized after 5 minutes of reperfusion. Metabolomic analysis of citric acid cycle intermediates demonstrated that cardioprotection was associated with a reversible shutdown of mitochondrial glucose metabolism during ischemia and early reperfusion at onset of but not at late type 2 diabetes. CONCLUSIONS: The metabolic alterations of type 2 diabetes are associated with protection against IR injury at onset but detrimental effects in late diabetes mellitus consistent with progressive dysfunction of glucose oxidation. These findings may explain the variable efficacy of cardioprotective interventions in individuals with type 2 diabetes.

  14. Association of Postoperative High-Sensitivity Troponin Levels With Myocardial Injury and 30-Day Mortality Among Patients Undergoing Noncardiac Surgery.

    Science.gov (United States)

    Devereaux, P J; Biccard, Bruce M; Sigamani, Alben; Xavier, Denis; Chan, Matthew T V; Srinathan, Sadeesh K; Walsh, Michael; Abraham, Valsa; Pearse, Rupert; Wang, C Y; Sessler, Daniel I; Kurz, Andrea; Szczeklik, Wojciech; Berwanger, Otavio; Villar, Juan Carlos; Malaga, German; Garg, Amit X; Chow, Clara K; Ackland, Gareth; Patel, Ameen; Borges, Flavia Kessler; Belley-Cote, Emilie P; Duceppe, Emmanuelle; Spence, Jessica; Tandon, Vikas; Williams, Colin; Sapsford, Robert J; Polanczyk, Carisi A; Tiboni, Maria; Alonso-Coello, Pablo; Faruqui, Atiya; Heels-Ansdell, Diane; Lamy, Andre; Whitlock, Richard; LeManach, Yannick; Roshanov, Pavel S; McGillion, Michael; Kavsak, Peter; McQueen, Matthew J; Thabane, Lehana; Rodseth, Reitze N; Buse, Giovanna A Lurati; Bhandari, Mohit; Garutti, Ignacia; Jacka, Michael J; Schünemann, Holger J; Cortes, Olga Lucía; Coriat, Pierre; Dvirnik, Nazari; Botto, Fernando; Pettit, Shirley; Jaffe, Allan S; Guyatt, Gordon H

    2017-04-25

    Little is known about the relationship between perioperative high-sensitivity troponin T (hsTnT) measurements and 30-day mortality and myocardial injury after noncardiac surgery (MINS). To determine the association between perioperative hsTnT measurements and 30-day mortality and potential diagnostic criteria for MINS (ie, myocardial injury due to ischemia associated with 30-day mortality). Prospective cohort study of patients aged 45 years or older who underwent inpatient noncardiac surgery and had a postoperative hsTnT measurement. Starting in October 2008, participants were recruited at 23 centers in 13 countries; follow-up finished in December 2013. Patients had hsTnT measurements 6 to 12 hours after surgery and daily for 3 days; 40.4% had a preoperative hsTnT measurement. A modified Mazumdar approach (an iterative process) was used to determine if there were hsTnT thresholds associated with risk of death and had an adjusted hazard ratio (HR) of 3.0 or higher and a risk of 30-day mortality of 3% or higher. To determine potential diagnostic criteria for MINS, regression analyses ascertained if postoperative hsTnT elevations required an ischemic feature (eg, ischemic symptom or electrocardiography finding) to be associated with 30-day mortality. Among 21 842 participants, the mean age was 63.1 (SD, 10.7) years and 49.1% were female. Death within 30 days after surgery occurred in 266 patients (1.2%; 95% CI, 1.1%-1.4%). Multivariable analysis demonstrated that compared with the reference group (peak hsTnT postoperative hsTnT levels of 20 to less than 65 ng/L, 65 to less than 1000 ng/L, and 1000 ng/L or higher had 30-day mortality rates of 3.0% (123/4049; 95% CI, 2.6%-3.6%), 9.1% (102/1118; 95% CI, 7.6%-11.0%), and 29.6% (16/54; 95% CI, 19.1%-42.8%), with corresponding adjusted HRs of 23.63 (95% CI, 10.32-54.09), 70.34 (95% CI, 30.60-161.71), and 227.01 (95% CI, 87.35-589.92), respectively. An absolute hsTnT change of 5 ng/L or higher was associated with an

  15. Irreversible Simulated Tempering

    Science.gov (United States)

    Sakai, Yuji; Hukushima, Koji

    2016-10-01

    An extended ensemble Monte Carlo algorithm is proposed by introducing a violation of the detailed balance condition to the update scheme of the inverse temperature in simulated tempering. Our method, irreversible simulated tempering, is constructed on the basis of the framework of the skew detailed balance condition. By applying this method to the ferromagnetic Ising model in two dimensions on a square lattice as a benchmark, the dynamical behavior of the inverse temperature and an autocorrelation function of the magnetization are studied numerically. It is found that the relaxation dynamics of the inverse temperature qualitatively change from diffusive to ballistic on violating the detailed balance condition. Consequently, the autocorrelation time of the magnetization is several times smaller than that for the conventional algorithm satisfying the detailed balance condition.

  16. Nonequilibrium and irreversibility

    CERN Document Server

    Gallavotti, Giovanni

    2014-01-01

    This book concentrates on the properties of the stationary states in chaotic systems of particles or fluids, leaving aside the theory of the way they can be reached. The stationary states of particles or of fluids (understood as probability distributions on microscopic configurations or on the fields describing continua) have received important new ideas and data from numerical simulations and reviews are needed. The starting point is to find out which time invariant distributions come into play in physics. A special feature of this book is the historical approach. To identify the problems the author analyzes the papers of the founding fathers Boltzmann, Clausius and Maxwell including translations of the relevant (parts of ) historical documents. He also establishes a close link between treatment of irreversible phenomena in statistical mechanics and the theory of chaotic systems at and beyond the onset of turbulence as developed by Sinai, Ruelle, Bowen (SRB) and others: the author gives arguments intending t...

  17. The role of muscarinic receptors in the beneficial effects of adenosine against myocardial reperfusion injury in rats.

    Directory of Open Access Journals (Sweden)

    Lei Sun

    Full Text Available Adenosine, a catabolite of ATP, displays a wide variety of effects in the heart including regulation of cardiac response to myocardial ischemia and reperfusion injury. Nonetheless, the precise mechanism of adenosine-induced cardioprotection is still elusive. Isolated Sprague-Dawley rat hearts underwent 30 min global ischemia and 120 min reperfusion using a Langendorff apparatus. Both adenosine and acetylcholine treatment recovered the post-reperfusion cardiac function associated with adenosine and muscarinic receptors activation. Simultaneous administration of adenosine and acetylcholine failed to exert any additive protective effect, suggesting a shared mechanism between the two. Our data further revealed a cross-talk between the adenosine and acetylcholine receptor signaling in reperfused rat hearts. Interestingly, the selective M(2 muscarinic acetylcholine receptor antagonist methoctramine significantly attenuated the cardioprotective effect of adenosine. In addition, treatment with adenosine upregulated the expression and the maximal binding capacity of muscarinic acetylcholine receptor, which were inhibited by the selective A(1 adenosine receptor antagonist 8-Cyclopentyl-1,3-dipropylxanthine (DPCPX and the nitric oxide synthase inhibitor N(ω-nitro-L-arginine methyl ester (L-NAME. These data suggested a possible functional coupling between the adenosine and muscarinic receptors behind the observed cardioprotection. Furthermore, nitric oxide was found involved in triggering the response to each of the two receptor agonist. In summary, there may be a cross-talk between the adenosine and muscarinic receptors in ischemic/reperfused myocardium with nitric oxide synthase might serve as the distal converging point. In addition, adenosine contributes to the invigorating effect of adenosine on muscarinic receptor thereby prompting to regulation of cardiac function. These findings argue for a potentially novel mechanism behind the adenosine

  18. Association of chronic kidney disease with periprocedural myocardial injury after elective stent implantation: A single center prospective cohort study.

    Science.gov (United States)

    Jerkic, Helena; Letilovic, Tomislav; Stipinovic, Mario; Pocanic, Darko; Catic, Jasmina; Knotek, Mladen

    2016-11-01

    Coronary artery disease (CAD) is the leading cause of mortality in patients with chronic kidney disease (CKD). Patients with CKD who undergo percutaneous coronary intervention (PCI) may have more ischemic events than patients without CKD. The aim of our study was to determine the incidence of periprocedural myocardial injury (PMI) after elective stent implantation in patients with CKD using the Third Joint ESC/ACCF/AHA/WHF PMI definition.In a single center prospective cohort study, we enrolled 344 consecutive patients who underwent elective PCI in a period of 39 months. Serum troponin I (cTnI) concentrations were measured at baseline and at 8 and 16 hours after PCI. Periprocedural increase of cTnI, according to the most recent PMI definition, was used to define both the presence and intensity of PMI. Patients were further stratified according to the estimated glomerular filtration rate (eGFR) using 4 variable Modification of Diet in Renal Disease (MDRD) equation: control group with eGFR >90 mL/min/1.73 m and the CKD group with eGFR PMI in the control (>90 mL/min/1.73 m) and the CKD group (PMI compared to the control group. Further analyses of our data showed angina pectoris CCS IV, bare metal stent (BMS) implantation, and treatment with angiotensin-converting enzyme inhibitors (ACEI) as independent predictors of PMI. Furthermore, the presence of hypertension was inversely related to the occurrence of PMI.Applying the new guidelines for PMI and using the eGFR equation most suitable for our patients, we found no association between PMI and CKD. Further analyses showed other factors that could potentially influence the occurrence of PMI.

  19. Incidence and mortality of acute kidney injury after myocardial infarction: a comparison between KDIGO and RIFLE criteria.

    Directory of Open Access Journals (Sweden)

    Fernando B Rodrigues

    Full Text Available BACKGROUND: Acute kidney injury (AKI increases the risk of death after acute myocardial infarction (AMI. Recently, a new AKI definition was proposed by the Kidney Disease Improving Global Outcomes (KDIGO organization. The aim of the current study was to compare the incidence and the early and late mortality of AKI diagnosed by RIFLE and KDIGO criteria in the first 7 days of hospitalization due to an AMI. METHODS AND RESULTS: In total, 1,050 AMI patients were prospectively studied. AKI defined by RIFLE and KDIGO occurred in 14.8% and 36.6% of patients, respectively. By applying multivariate Cox analysis, AKI was associated with an increased adjusted hazard ratio (AHR for 30-day death of 3.51 (95% confidence interval [CI] 2.35-5.25, p<0.001 by RIFLE and 3.99 (CI 2.59-6.15, p<0.001 by KDIGO and with an AHR for 1-year mortality of 1.84 (CI 1.12-3.01, p=0.016 by RIFLE and 2.43 (CI 1.62-3.62, p<0.001 by KDIGO. The subgroup of patients diagnosed as non-AKI by RIFLE but as AKI by KDIGO criteria had also an increased AHR for death of 2.55 (1.52-4.28 at 30 days and 2.28 (CI 1.46-3.54 at 1 year (p<0.001. CONCLUSIONS: KDIGO criteria detected substantially more AKI patients than RIFLE among AMI patients. Patients diagnosed as AKI by KDIGO but not RIFLE criteria had a significantly higher early and late mortality. In this study KDIGO criteria were more suitable for AKI diagnosis in AMI patients than RIFLE criteria.

  20. Effect of felodipine on myocardial and renal injury induced by aldosterone-high salt hypertension in uninephrectomized rats

    Directory of Open Access Journals (Sweden)

    B.B. Matsubara

    2010-05-01

    Full Text Available It has been recently shown that calcium channel blockers might have a protective effect on cardiac fibrogenesis induced by aldosterone. The objective of this study was to evaluate the protective effect of felodipine, a dihydropyridine calcium channel blocker, against heart and kidney damage caused by aldosterone-high sodium intake in uninephrectomized rats. Wistar rats were divided into three groups: CNEP (uninephrectomized + 1% NaCl in the drinking water, N = 9; ALDO (same as CNEP group plus continuous infusion of 0.75 µg/h aldosterone, N = 12; ALDOF (same as ALDO group plus 30 mg·kg-1·day-1 felodipine in the drinking water, N = 10. All results were compared with those of age-matched, untreated rats (CTL group, N = 10. After 6 weeks, tail cuff blood pressure was recorded and the rats were killed for histological analysis. Blood pressure (mmHg was significantly elevated (P < 0.05 in ALDO (180 ± 20 and ALDOF (168 ± 13 compared to CTL (123 ± 12 and CNEP (134 ± 13. Heart damage (lesion scores - median and interquartile range was 7.0 (5.5-8.0 in ALDO and was fully prevented in ALDOF (1.5; 1.0-2.0. Also, left ventricular collagen volume fraction (% in ALDOF (2.9 ± 0.5 was similar to CTL (2.9 ± 0.5 and CNEP (3.4 ± 0.4 and decreased compared to ALDO (5.1 ± 1.6. Felodipine partially prevented kidney injury since the damage score for ALDOF (2.0; 2.0-3.0 was significantly decreased compared to ALDO (7.5; 4.0-10.5, although higher than CTL (null score. Felodipine has a protective effect on the myocardium and kidney as evidenced by decreased perivascular inflammation, myocardial necrosis and fibrosis.

  1. Serum Fatty Acids, Traditional Risk Factors, and Comorbidity as Related to Myocardial Injury in an Elderly Population with Acute Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Kristian Laake

    2016-01-01

    Full Text Available Background. Epidemiological and randomized clinical trials indicate that marine polyunsaturated n-3 fatty acids (n-3 PUFAs may have cardioprotective effects. Aim. Evaluate the associations between serum fatty acid profile, traditional risk factors, the presence of cardiovascular diseases (CVD, and peak Troponin T (TnT levels in elderly patients with an acute myocardial infarction (AMI. Materials and Methods. Patients (n=299 consecutively included in the ongoing Omega-3 fatty acids in elderly patients with myocardial infarction (OMEMI trial were investigated. Peak TnT was registered during the hospital stay. Serum fatty acid analysis was performed 2–8 weeks later. Results. No significant correlations between peak TnT levels and any of the n-3 PUFAs were observed. However, patients with a history of atrial fibrillation had significantly lower docosahexaenoic acid levels than patients without. Significantly lower peak TnT levels were observed in patients with a history of hyperlipidemia, angina, MI, atrial fibrillation, intermittent claudication, and previous revascularization (all p<0.02. Conclusions. In an elderly population with AMI, no association between individual serum fatty acids and estimated myocardial infarct size could be demonstrated. However, a history of hyperlipidemia and the presence of CVD were associated with lower peak TnT levels, possibly because of treatment with cardioprotective medications.

  2. Distinct properties and metabolic mechanisms of postresuscitation myocardial injuries in ventricular fibrillation cardiac arrest versus asphyxiation cardiac arrest in a porcine model

    Institute of Scientific and Technical Information of China (English)

    Wu Caijun; Li Chunsheng; Zhang Yi; Yang Jun

    2014-01-01

    Background The two most prevalent causes of sudden cardiac death are ventricular fibrillation cardiac arrest (VFCA) and asphyxiation cardiac arrest (ACA).Profound postresuscitation myocardial dysfunction has been demonstrated in both VFCA and ACA animal models.Our study aimed to characterize the two porcine models of cardiac arrest and postresuscitation myocardial metabolism dysfunction.Methods Thirty-two pigs were randomized into two groups.The VFCA group (n=16) were subject to programmed electrical stimulation and the ACA group (n=16) underwent endotracheal tube clamping to induce cardiac arrest (CA).Once induced,CA remained untreated for a period of 8 minutes.Two minutes following initiation of cardiopulmonary resuscitation (CPR),defibrillation was attempted until return of spontaneous circulation (ROSC) was achieved or animals died.To assess myocardial metabolism,18F-FluoroDeoxyGlucose Positron Emission Tomography was performed at baseline and 4 hours after ROSC.Results ROSC was 100% successful in VFCA and 50% successful in ACA.VFCA had better mean arterial pressure and cardiac output after ROSC than ACA.Arterial blood gas analysis indicated more detrimental metabolic disturbances in ACA compared with VFCA after ROSC (ROSC 0.5 hours,pH:7.01±0.06 vs.7.21±0.03,P<0.01; HCO3-:(15.83±2.31 vs.20.11±1.83) mmol/L,P<0.01; lactate:(16.22±1.76 vs.5.84±1.44) mmol/L,P<0.01).Myocardial metabolism imaging using Positron Emission Tomography demonstrated that myocardial injuries after ACA were more severe and widespread than after VFCA at 4 hours after ROSC (the maximum standardized uptake value of the whole left ventricular:1.00±0.17 vs.1.93±0.27,P<0.01).Lower contents of myocardial energy metabolism enzymes (Na+-K+-ATPase enzyme activity,Ca2+-ATPase enzyme activity,superoxide dismutase and phosphodiesterase) were found in ACA relative to VFCA.Conclusions Compared with VFCA,ACA causes more severe myocardium injury and metabolism hindrance,therefore they

  3. Effectiveness of Panax ginseng on Acute Myocardial Ischemia Reperfusion Injury Was Abolished by Flutamide via Endogenous Testosterone-Mediated Akt Pathway.

    Science.gov (United States)

    Pei, Luo; Shaozhen, Hou; Gengting, Dong; Tingbo, Chen; Liang, Liu; Hua, Zhou

    2013-01-01

    Mechanisms for Panax ginseng's cardioprotective effect against ischemia reperfusion injury involve the estrogen-mediated pathway, but little is known about the role of androgen. A standardized Panax ginseng extract (RSE) was orally given with or without flutamide in a left anterior descending coronary artery ligation rat model. Infarct size, CK and LDH activities were measured. Time-related changes of NO, PI3K/Akt/eNOS signaling, and testosterone concentration were also investigated. RSE (80 mg/kg) significantly inhibited myocardial infarction and CK and LDH activities, while coadministration of flutamide abolished this effect of RSE. NO was increased by RSE and reached a peak after 15 min of ischemia; however, flutamide cotreatment suppressed this elevation. Western blot analysis showed that RSE significantly reversed the decreases of expression and activation of PI3K, Akt, and eNOS evoked by ischemia, whereas flutamide attenuated the effects of these protective mechanisms induced by RSE. RSE completely reversed the dropping of endogenous testosterone level induced by I/R injury. Flutamide plus RSE treatment not only abolished RSE's effect but also produced a dramatic change on endogenous testosterone level after pretreatment and ischemia. Our results for the first time indicate that blocking androgen receptor abolishes the ability of Panax ginseng to protect the heart from myocardial I/R injury.

  4. 心肌损伤标记物在老年急性心肌梗死中的临床应用%The Clinical Application of Myocardial Injury Markers in Acute Myocardial Infarction

    Institute of Scientific and Technical Information of China (English)

    吴宁

    2015-01-01

    目的:探讨心肌损伤标记物在老年急性心肌梗死的临床应用。方法选取2014年1月~2015年1月在我院就诊的43例老年急性心肌梗死患者为心肌梗死组,选取同期在我院就诊有胸闷气短等症状的老年患者为非典型组,选取同期在我院体检的40例健康受试者,为对照组,比较三组患者血清中的Myo、CK-MB、cTnI的含量及急性心急梗死患者8h内急性心肌损伤标记物早期敏感性。结果8h后,对三组患者血清中的Myo、CK-Mb、cTn1的含量比较结果显示,心肌梗死组和非典型组血清中的Myo、CK-Mb、cTn1的含量与对照组相比,高于对照组血清中Myo、CK-Mb、cTn1的含量,差异具有统计学意义(P<0.05),对心肌梗死组和非典型组两组患者血清中Myo、CK-Mb、cTn1的含量比较结果显示,非典型组血清中Myo、CK-Mb、cTn1的含量高于心肌梗死组,差异具有统计学意义(P<0.05)。cTn1、CK-MB、Mb三者对于急性心肌梗死早期诊断的敏感性分别为97.9%、95.8%、100%。说明血清中的Myo、CK-Mb、cTn1作为老年急性心肌梗死诊断的标志物具有较高的早期敏感性。结论血清中的Myo、CK-Mb、cTn1的含量可以作为心肌损伤标记物,具有较高的特异性和灵敏性,为临床老年患者急性心肌梗死的诊断提供了依据。%Objective To evaluate the clinical application of markers of myocardial damage in acute myocardial infarction. Methods 43 cases of patients with acute myocardial infarction myocardial infarction were chosen in January 2014~January 2015 in our hospital, choose the same period in our hospital have shortness of breath and other symptoms in elderly patients with atypical group, choose the same period in our hospital examination 40 healthy subjects as the control group, three groups of serum Myo, CK-MB, cTnI within the content and acute impatient eight hours of acute myocardial infarction injury markers early

  5. From instability to irreversibility.

    Science.gov (United States)

    Elskens, Y; Prigogine, I

    1986-08-01

    A canonical procedure transforming the unitary evolution group U(t) in a contracting semigroup W(t) for phase-space ensembles has been developed for Kolmogorov dynamical systems in a series of recent papers. This paper investigates the physical meaning of this transformation. We stress that, for sufficiently unstable dynamical systems in which phase-space points are identified with an arbitrary but finite precision, one must take into account the undiscernibility of trajectories having the same asymptotic behavior in the future. The fundamental objects of our description are thus bundles of converging trajectories. We show that such an ensemble, corresponding to initial conditions whose support has finite measure, is then represented by a distribution function (called a Boltzmann ensemble) that evolves to equilibrium under the action of a markovian semigroup. The usual Gibbs-Koopman ensembles satisfying the Liouville equation are recovered as a singular limit. This work validates Boltzmann's intuition for a class of unstable dynamical systems and appears as a step toward the derivation of equations exhibiting irreversibility at a microscopic level.

  6. Huangzhi Oral Liquid Prevents Arrhythmias by Upregulating Caspase-3 and Apoptosis Network Proteins in Myocardial Ischemia-Reperfusion Injury in Rats

    Directory of Open Access Journals (Sweden)

    Xu Ran

    2015-01-01

    Full Text Available To study the effect of Huangzhi oral liquid (HZOL on I/R after 2 h and 4 h and determine its regulatory function on caspase-3 and protein networks. 70 SD male rats were randomly divided into seven groups and established myocardial I/R injury model by ligating the left anterior descending coronary artery. Myocardial infarction model was defined by TTC staining and color of the heart. The levels of CK-MB, CTnI, C-RPL, SOD, and MDA were tested at 2 h and 4 h after reperfusion. HE staining and ultramicrostructural were used to observe the pathological changes. The apoptotic index (AI of cardiomyocyte was marked by TUNEL. The expression levels of caspase-3, p53, fas, Bcl-2, and Bax were tested by immunohistochemistry and western blot. HZOL corrected arrhythmia, improved the pathologic abnormalities, decreased CK-MB, CTnI, C-RPL, MDA, AI, caspase-3, p53, fas, and Bax, and increased SOD ans Bcl-2 with different times of myocardial reperfusion; this result was similar to the ISMOC (P>0.05. HZOL could inhibit arrhythmia at 2 and 4 h after I/R and ameliorate cardiac function, which was more significant at 4 h after reperfusion. This result may be related to decreased expression of caspase-3, p53, and fas and increased Bcl-2/Bax ratio.

  7. Protective Effects of Kaempferol against Myocardial Ischemia/Reperfusion Injury in Isolated Rat Heart via Antioxidant Activity and Inhibition of Glycogen Synthase Kinase-3β

    Directory of Open Access Journals (Sweden)

    Mingjie Zhou

    2015-01-01

    Full Text Available Objective. This study aimed to evaluate the protective effect of kaempferol against myocardial ischemia/reperfusion (I/R injury in rats. Method. Left ventricular developed pressure (LVDP and its maximum up/down rate (±dp/dtmax were recorded as myocardial function. Infarct size was detected with 2,3,5-triphenyltetrazolium chloride staining. Cardiomyocyte apoptosis was determined using terminal deoxynucleotidyl nick-end labeling (TUNEL. The levels of creatine kinase (CK, lactate dehydrogenase (LDH, malondialdehyde (MDA, superoxide dismutase (SOD, glutathione/glutathione disulfide (GSH/GSSG ratio, and tumor necrosis factor-alpha (TNF-α were determined using enzyme linked immunosorbent assay (ELISA. Moreover, total glycogen synthase kinase-3β (GSK-3β, phospho-GSK-3β (P-GSK-3β, precaspase-3, cleaved caspase-3, and cytoplasm cytochrome C were assayed using Western blot analysis. Results. Pretreatment with kaempferol significantly improved the recovery of LVDP and ±dp/dtmax, as well as increased the levels of SOD and P-GSK-3β and GSH/GSSG ratio. However, the pretreatment reduced myocardial infarct size and TUNEL-positive cell rate, as well as decreased the levels of cleaved caspase-3, cytoplasm cytochrome C, CK, LDH, MDA, and TNF-α. Conclusion. These results suggested that kaempferol provides cardioprotection via antioxidant activity and inhibition of GSK-3β activity in rats with I/R.

  8. Potential Effect of L-Carnitine on the Prevention of Myocardial Injury after Coronary Artery Bypass Graft Surgery

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    Farzaneh Dastan

    2015-10-01

    Full Text Available Background: L-carnitine has been demonstrated to confer cardiac protection against ischemia reperfusion injury in animals. This study evaluates the effects of L-carnitine administration on cardiac biomarkers after coronary artery bypass graft (CABG surgery.Methods: One hundred thirty-four patients undergoing elective CABG surgery, without a history of myocardial ischemia or previous L-carnitine treatment, were enrolled and randomly assigned to an L-carnitine group ([n = 67], 3000 mg/d, started 2 days preoperatively and continued for 2 days after surgery or a control group (n = 67. CK-MB (creatine kinase, muscle- brain subunits and troponin T (TnT levels were assessed in all the patients before surgery as baseline levels and at 8 and 24 hours postoperatively.Results: Our study included 134 patients (99 [73.8%] males at a mean ± SD age of 59.94 ± 8.61 years who were candidates for CABG and randomized them into control or L-carnitine groups. The baseline demographic characteristics, including age (60.01 ± 9.23 in the L-carnitine group vs. 59.88 ± 7.98 in the control group and sex (54 [80.6%] in the L-carnitine group vs. 45 [67.2%] in the control group did not show any significant differences (p value=0.93 and 0.08, respectively. Patients in the L-carnitine group had lower levels of CK-MB (mean ± SD, 25.06 ± 20.29 in the L-carnitine group vs. 24.26 ± 14.61 in the control group, but the difference was not significant (p value = 0.28. TnT levels also showed no significant differences between the two groups (399.50 ± 378.91 in the L-carnitine group vs. 391.48 ± 222.02 in the control group; p value = 0.34. Conclusion: In this population of intermediate- to high-risk patients undergoing CABG surgery, L-carnitine did not reduce CK-MB and TnT levels.

  9. Protective effect of mangiferin on myocardial ischemia-reperfusion injury in streptozotocin-induced diabetic rats: role of AGE-RAGE/MAPK pathways.

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    Suchal, Kapil; Malik, Salma; Khan, Sana Irfan; Malhotra, Rajiv Kumar; Goyal, Sameer N; Bhatia, Jagriti; Kumari, Santosh; Ojha, Shreesh; Arya, Dharamvir Singh

    2017-02-09

    Hyperglycemia induced advanced glycation end products-receptor for advanced glycation end products (AGE-RAGE) activation is thought to involve in the development of cardiovascular disease in diabetics. Activation of AGE-RAGE axis results in the oxidative stress and inflammation. Mangiferin is found in the bark of mango tree and is known to treat diseases owing to its various biological activities. Thus, this study was designed to evaluate the effect of mangiferin in ischemia-reperfusion (IR) induced myocardial injury in diabetic rats. A single injection of STZ (70 mg/kg; i.p.) was injected to male albino Wistar rats to induce diabetes. After confirmation of diabetes, rats were administered vehicle (2 ml/kg; i.p.) and mangiferin (40 mg/kg; i.p.) for 28 days. On 28(th) day, left anterior descending coronary artery was ligated for 45 min and then reperfused for 60 min. Mangiferin treatment significantly improved cardiac function, restored antioxidant status, reduced inflammation, apoptosis and maintained myocardial architecture. Furthermore, mangiferin significantly inhibited the activation of AGE-RAGE axis, c-Jun N-terminal kinase (JNK) and p38 and increased the expression of extracellular regulated kinase 1/2 (ERK1/2) in the myocardium. Thus, mangiferin attenuated IR injury in diabetic rats by modulation of AGE-RAGE/MAPK pathways which further prevented oxidative stress, inflammation and apoptosis in the myocardium.

  10. The Effect of Remote Ischemic Conditioning and Glyceryl Trinitrate on Perioperative Myocardial Injury in Cardiac Bypass Surgery Patients: Rationale and Design of the ERIC-GTN Study.

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    Hamarneh, Ashraf; Sivaraman, Vivek; Bulluck, Heerajnarain; Shanahan, Hilary; Kyle, Bonnie; Ramlall, Manish; Chung, Robin; Jarvis, Claire; Xenou, Maria; Ariti, Cono; Cordery, Roger; Yellon, Derek M; Hausenloy, Derek J

    2015-11-01

    Remote ischemic conditioning (RIC) using transient limb ischemia/reperfusion has been reported to reduce perioperative myocardial injury in patients undergoing coronary artery bypass grafting and/or valve surgery. The role of intravenous glyceryl trinitrate (GTN) therapy administered during cardiac surgery as a cardioprotective agent and whether it interferes with RIC cardioprotection is not clear and is investigated in the ERIC-GTN trial ( http://www.clinicaltrials.gov: NCT01864252). The ERIC-GTN trial is a single-site, double-blind, randomized, placebo-controlled study. Consenting adult patients (age > 18 years) undergoing elective coronary artery bypass grafting ± valve surgery with blood cardioplegia will be eligible for inclusion. Two hundred sixty patients will be randomized to 1 of 4 treatment groups following anesthetic induction: (1) RIC alone, a RIC protocol comprising three 5-minute cycles of simultaneous upper-arm and thigh cuff inflation/deflation followed by an intravenous (IV) placebo infusion; (2) GTN alone, a simulated sham RIC protocol followed by an IV GTN infusion; (3) RIC + GTN, a RIC protocol followed by an IV GTN infusion; and (4) neither RIC nor GTN, a sham RIC protocol followed by IV placebo infusion. The primary endpoint will be perioperative myocardial injury as quantified by the 72-hour area-under-the-curve serum high-sensitivity troponin T. The ERIC-GTN trial will determine whether intraoperative GTN therapy is cardioprotective during cardiac surgery and whether it affects RIC cardioprotection.

  11. Effect of Intracoronary Infusion of Bone Marrow Mononuclear Cells or Peripheral Endothelial Progenitor Cells on Myocardial Ischemia-reperfusion Injury in Mini-swine

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    Chong-jian Li; Ji-lin Chen; Jian-jun Li; Run-lin Gao; Yue-jin Yang; Feng-huan Hu; Wei-xian Yang; Shi-jie You; Lai-feng Song; Ying-mao Ruan; Shu-bin Qiao

    2010-01-01

    Objective To simulate and assess the clinical effect of intracoronary infusion of bone marrow mono-nuclear cells or peripheral endothelial progenitor cells on myocardial reperfusion injury in mini-swine model.Methods Twenty-three mini-swine with myocardial reperfusion injury were used as designed in the study protocol. About (3.54+0.90)x108 bone marrow mononudear cells (MNC group, n=9) or (1.16± 1.07)×10 endothelial progenitor cells (EPC group, n=7) was infused into the affected coronary segment of the swine. The other mini-swine were infused with phosphate buffered saline as control (n=7). Echocardio-graphy and hemodynamic studies were performed before and 4 weeks after cell infusion. Myocardium infarc-tion size was calculated. Stem cell differentiation was analyzed under a transmission electromicroscope.Results Left ventricular ejection fraction dropped by 0% in EPC group, 2% in MNC group, and 10% in the control group 4 weeks after cell infusion, respectively (P0.05). EPC decreased total infarction size more than MNC did (1.60±0.26 cm vs. 3.71±1.38 cm, P<0.05). Undermature endothelial cells and myocytes were found under transmission electromicroscope.Conclusions Transplantation of either MNC or EPC may be beneficial to cardiac systolic function, but might not has obvious effect on diastolic function, Intracoronary infusion of EPC might be better than MNC in controlling infarction size. Both MNC and EPC may stimulate angiogenesis, inhibit fibrogenesis, and differentiate into myocardial cells.

  12. 心肌损伤标志物在儿童心肌损伤性疾病诊断中的临床价值评估%Evaluation of myocardial injury markers in the diagnosis of pediatric myocardial injury diseases

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    马丽娟

    2015-01-01

    Pediatric cardiac injury is common in primary heart disease and secondary systemic diseases.The pathophysiological processes include ischemic injury or direct injury, as well as focal or diffuse myocardial inflammatory lesions.Myocardial injury markers, including myoglobin, creatine kinase isoenzyme muscle B and troponin, are first used for the diagnosis of acute coronary syndrome(ACS) in adult, and have greatly improved the efficiency of diagnosis with their sensitivity and specificity.However, due to the very different pathogenesis of myocardial injury in pediatric and adult ACS, as well as the particularity that children are in continuous growth and development, it is necessary to evaluate the value of the myocardial injury markers and their biological reference intervals in pediatrics.%儿童心肌损伤常见于原发性心脏病和继发于全身性的疾病,病生理过程包括缺血性损伤或直接损伤,为心肌局灶性或弥漫性炎性病变。临床上应用心肌损伤标志物始于成人急性冠状动脉综合征( ACS),主要有肌红蛋白、肌酸磷酸激酶同工酶、肌钙蛋白等,其敏感度、特异度的逐步提高使ACS的诊断进入小时时代。但由于儿童心肌损伤和成人ACS的发病机制多不同,且儿童生长发育不断持续的特殊性,有必要对儿科进行该类检测应用价值的评估,生物参考区间的管理,综合判断心肌损伤标志物在儿科的应用价值。(中华检验医学杂志,2015,38:370-372)

  13. Myocardial Ablation of G Protein-Coupled Receptor Kinase 2 (GRK2 Decreases Ischemia/Reperfusion Injury through an Anti-Intrinsic Apoptotic Pathway.

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    Qian Fan

    Full Text Available Studies from our lab have shown that decreasing myocardial G protein-coupled receptor kinase 2 (GRK2 activity and expression can prevent heart failure progression after myocardial infarction. Since GRK2 appears to also act as a pro-death kinase in myocytes, we investigated the effect of cardiomyocyte-specific GRK2 ablation on the acute response to cardiac ischemia/reperfusion (I/R injury. To do this we utilized two independent lines of GRK2 knockout (KO mice where the GRK2 gene was deleted in only cardiomyocytes either constitutively at birth or in an inducible manner that occurred in adult mice prior to I/R. These GRK2 KO mice and appropriate control mice were subjected to a sham procedure or 30 min of myocardial ischemia via coronary artery ligation followed by 24 hrs reperfusion. Echocardiography and hemodynamic measurements showed significantly improved post-I/R cardiac function in both GRK2 KO lines, which correlated with smaller infarct sizes in GRK2 KO mice compared to controls. Moreover, there was significantly less TUNEL positive myocytes, less caspase-3, and -9 but not caspase-8 activities in GRK2 KO mice compared to control mice after I/R injury. Of note, we found that lowering cardiac GRK2 expression was associated with significantly lower cytosolic cytochrome C levels in both lines of GRK2 KO mice after I/R compared to corresponding control animals. Mechanistically, the anti-apoptotic effects of lowering GRK2 expression were accompanied by increased levels of Bcl-2, Bcl-xl, and increased activation of Akt after I/R injury. These findings were reproduced in vitro in cultured cardiomyocytes and GRK2 mRNA silencing. Therefore, lowering GRK2 expression in cardiomyocytes limits I/R-induced injury and improves post-ischemia recovery by decreasing myocyte apoptosis at least partially via Akt/Bcl-2 mediated mitochondrial protection and implicates mitochondrial-dependent actions, solidifying GRK2 as a pro-death kinase in the heart.

  14. Hypotheses, rationale, design, and methods for prognostic evaluation of cardiac biomarker elevation after percutaneous and surgical revascularization in the absence of manifest myocardial infarction. A comparative analysis of biomarkers and cardiac magnetic resonance. The MASS-V Trial

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    Hueb Whady

    2012-08-01

    Full Text Available Abstract Background Although the release of cardiac biomarkers after percutaneous (PCI or surgical revascularization (CABG is common, its prognostic significance is not known. Questions remain about the mechanisms and degree of correlation between the release, the volume of myocardial tissue loss, and the long-term significance. Delayed-enhancement of cardiac magnetic resonance (CMR consistently quantifies areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac biomarkers, we will evaluate the extent of irreversible injury in patients undergoing PCI and CABG and relate it to postprocedural modifications in cardiac biomarkers and long-term prognosis. Methods/Design The study will include 150 patients with multivessel coronary artery disease (CAD with left ventricle ejection fraction (LVEF and a formal indication for CABG; 50 patients will undergo CABG with cardiopulmonary bypass (CPB; 50 patients with the same arterial and ventricular condition indicated for myocardial revascularization will undergo CABG without CPB; and another 50 patients with CAD and preserved ventricular function will undergo PCI using stents. All patients will undergo CMR before and after surgery or PCI. We will also evaluate the release of cardiac markers of necrosis immediately before and after each procedure. Primary outcome considered is overall death in a 5-year follow-up. Secondary outcomes are levels of CK-MB isoenzyme and I-Troponin in association with presence of myocardial fibrosis and systolic left ventricle dysfunction assessed by CMR. Discussion The MASS-V Trial aims to establish reliable values for parameters of enzyme markers of myocardial necrosis in the absence of manifest myocardial infarction after mechanical interventions. The establishments of these indices have diagnostic value and clinical prognosis and therefore require relevant and different therapeutic measures. In daily practice

  15. TAK-242 Protects Against Apoptosis in Coronary Microembolization-Induced Myocardial Injury in Rats by Suppressing TLR4/NF-κB Signaling Pathway

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    Xian-tao Wang

    2017-03-01

    Full Text Available Background/Aims: Myocardial apoptosis is heavily implicated in the myocardial injury caused by coronary microembolization (CME, and toll-like receptor 4 (TLR4 is considered to be involved in this apoptotic cascade. Therefore, the present study was designed to investigate the role of TLR4/NF-κB signaling pathway regulated by TAK-242, a selective TLR4 signal transduction inhibitor, in the myocardial apoptosis after CME in rats. Methods: Forty-five rats were randomized (random number into three groups: sham, CME and CME + TAK-242 (n = 15 per group.CME was induced by injecting polyethylene microspheres (42µm into the left ventricular except the sham group. CME + TAK-242 group was treated with TAK-242 (2mg/kg via the tail vein 30 minutes before CME modeling. Cardiac function was evaluated 6 hours after operation. Tissue biopsy was stained with HBFP to measure the size of micro-infarction area. TUNEL staining was used to detect myocardial apoptosis. Western blot and qPCR were used to evaluate the expression of TLR4, MyD88, NF-κB p65, p-IκBα and Cleaved caspase-3. Results: Cardiac function in the CME group and CME + TAK-242 group were significantly decreased compared with the sham group (P < 0.05 and the micro-infarction area, the apoptotic index, the expression of TLR4, NF-κB p65, p-IκBα and Cleaved caspase-3 were increased significantly (P < 0.05. Cardiac function in the CME + TAK-242 group was significantly improved compared with the CME group (P < 0.05 and the micro-infarction area, the apoptotic index, the expression of TLR4, MyD88, NF-κB p65, p-IκBα and Cleaved caspase-3 were decreased significantly (P < 0.05. Conclusions: TAK-242 can effectively improve CME-induced cardiac dysfunction by regulating TLR4/NF-κB signaling pathway and then reducing the myocardial apoptosis.

  16. Knockout of the tumor necrosis factor α receptor 1 gene can up-regulate erythropoietin receptor during myocardial ischemia-reperfusion injury in mice

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    LI Chang-ling; JIANG Jun; FAN You-qi; FU Guo-sheng; WANG Jia-nan; FAN Wei-ming

    2009-01-01

    Background Tumor necrosis factor α receptor 1 (TNFαR1) plays an important role in the signal pathway of apoptosis.The objective of this study was to investigate the effects of TNFaR1 knockout on the up-regulation of erythropoietin receptor (Epo-R) and the coordinated anti-apoptosis functions during myocardial ischemia-reperfusion injury in mice.Methods The ischemia-reperfusion injury model for cardiomyocytes was performed by ligating the left circumflex branch artery of TNFαR1 knockout (P55-/-) C17 B6 mice, as well as wild-type (P55+/+) C17 B6 mice. Triphenyltetrazolium chloride (TTC) staining was performed to observe the damaged area of the heart. TUNEL staining and DNA fragmentation were used to identify apoptosis. Mitochondrial Bcl-2 and Bax as well as expression of Epo-R and its downstream genes (Jak-2, slat-5, Akt, IkB-α, HIF-1α) were measured by Western blotting. The gene knockout mice were assigned into those undergoing the apoptosis surgical model group (KO group), and those subjected to sham operation (Kos group). Similarly, wild-type mice were either exposed to the surgical model (WT group) or subject to a sham operation (WTs group).Results The myocardial damage ratio of the wild-type group after the operation was significantly higher than that of the knockout group, (50.5±6.4)% vs (36.9±6.9)%, P<0.01. Similarly, TUNEL positive ratio of the wild-type group was significantly higher than that of the knockout group, (63.1±5.6)% vs (42.1±4.7)%, P<0.01. The gray value ratios of Epo-R,Jak-2, stat-5, Akt, IkB-α, HIF-1 and mitochondrial Bcl-2 in the KO group were significantly higher than those of the WT group, P<0.05; however, mitochondrial Bax was significantly lower than that of the WT group significantly (P<0.05).Conclusions Using the ischemia-reperfusion injury model in mice, cardiomyocytes of TNFαR1 knockouts exhibited anti-apoptotic characteristics. This information could be used to coordinate the prevention of myocardial apoptosis by up

  17. Sildenafil Protects against Myocardial Ischemia-Reperfusion Injury Following Cardiac Arrest in a Porcine Model: Possible Role of the Renin-Angiotensin System.

    Science.gov (United States)

    Wang, Guoxing; Zhang, Qian; Yuan, Wei; Wu, Junyuan; Li, Chunsheng

    2015-11-12

    Sildenafil, a phosphodiesterase-5 inhibitor sold as Viagra, is a cardioprotector against myocardial ischemia/reperfusion (I/R) injury. Our study explored whether sildenafil protects against I/R-induced damage in a porcine cardiac arrest and resuscitation (CAR) model via modulating the renin-angiotensin system. Male pigs were randomly divided to three groups: Sham group, Saline group, and sildenafil (0.5 mg/kg) group. Thirty min after drug infusion, ventricular fibrillation (8 min) and cardiopulmonary resuscitation (up to 30 min) was conducted in these animals. We found that sildenafil ameliorated the reduced cardiac function and improved the 24-h survival rate in this model. Sildenafil partly attenuated the increases of plasma angiotensin II (Ang II) and Ang (1-7) levels after CAR. Sildenafil also decreased apoptosis and Ang II expression in myocardium. The increases of expression of angiotensin-converting-enzyme (ACE), ACE2, Ang II type 1 receptor (AT1R), and the Ang (1-7) receptor Mas in myocardial tissue were enhanced after CAR. Sildenafil suppressed AT1R up-regulation, but had no effect on ACE, ACE2, and Mas expression. Sildenafil further boosted the upregulation of endothelial nitric oxide synthase (eNOS), cyclic guanosine monophosphate (cGMP) and inducible nitric oxide synthase(iNOS). Collectively, our results suggest that cardioprotection of sildenafil in CAR model is accompanied by an inhibition of Ang II-AT1R axis activation.

  18. Antioxidative and cardioprotective effects of total flavonoids extracted from Dracocephalum moldavica L. against acute ischemia/reperfusion-induced myocardial injury in isolated rat heart.

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    Jiang, Jiangtao; Yuan, Xuan; Wang, Ting; Chen, Hongmei; Zhao, Hong; Yan, Xinyan; Wang, Zhiping; Sun, Xiling; Zheng, Qiusheng

    2014-03-01

    This study evaluates antioxidative and cardioprotective effects of total flavonoids extracted from Dracocephalum moldavica L. (DML). The total flavonoids showed remarkable scavenging effects against 1,1-diphenyl-2-picrylhydrazyl, hydroxyl and superoxide anion radicals in vitro. Compared with the ischemia/reperfusion (I/R) group as demonstrated by the use of improved Langendorff retrograde perfusion technology, the total flavonoids (5 μg/mL) pretreatment improved the heart rate and coronary flow, rised left ventricular developed pressure and decreased creatine kinase, lactate dehydrogenase levels in coronary flow. The infarct size/ischemic area at risk of DML-treated hearts was smaller than that of I/R group; the superoxide dismutase activity and glutathione/glutathione disulfide ratio increased and malondialdehyde content reduced obviously (P total flavonoids treatment groups. In conclusion, the total flavonoids possess obvious protective effects on myocardial I/R injury, which may be related to the improvement of myocardial oxidative stress states.

  19. Sildenafil Protects against Myocardial Ischemia-Reperfusion Injury Following Cardiac Arrest in a Porcine Model: Possible Role of the Renin-Angiotensin System

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    Guoxing Wang

    2015-11-01

    Full Text Available Sildenafil, a phosphodiesterase-5 inhibitor sold as Viagra, is a cardioprotector against myocardial ischemia/reperfusion (I/R injury. Our study explored whether sildenafil protects against I/R-induced damage in a porcine cardiac arrest and resuscitation (CAR model via modulating the renin-angiotensin system. Male pigs were randomly divided to three groups: Sham group, Saline group, and sildenafil (0.5 mg/kg group. Thirty min after drug infusion, ventricular fibrillation (8 min and cardiopulmonary resuscitation (up to 30 min was conducted in these animals. We found that sildenafil ameliorated the reduced cardiac function and improved the 24-h survival rate in this model. Sildenafil partly attenuated the increases of plasma angiotensin II (Ang II and Ang (1–7 levels after CAR. Sildenafil also decreased apoptosis and Ang II expression in myocardium. The increases of expression of angiotensin-converting-enzyme (ACE, ACE2, Ang II type 1 receptor (AT1R, and the Ang (1–7 receptor Mas in myocardial tissue were enhanced after CAR. Sildenafil suppressed AT1R up-regulation, but had no effect on ACE, ACE2, and Mas expression. Sildenafilfurther boosted the upregulation of endothelial nitric oxide synthase (eNOS, cyclic guanosine monophosphate (cGMP and inducible nitric oxide synthase(iNOS. Collectively, our results suggest that cardioprotection of sildenafil in CAR model is accompanied by an inhibition of Ang II-AT1R axis activation.

  20. Post myocardial infarction of the left ventricle: the course ahead seen by cardiac MRI

    Science.gov (United States)

    Masci, Pier Giorgio

    2012-01-01

    In the last decades, cardiac magnetic resonance imaging (MRI) has gained acceptance in cardiology community as an accurate and reproducible diagnostic imaging modality in patients with ischemic heart disease (IHD). In particular, in patients with acute myocardial infarction (MI) cardiac MRI study allows a comprehensive assessment of the pattern of ischemic injury in term of reversible and irreversible damage, myocardial hemorrhage and microvascular obstruction (MVO). Myocardial salvage index, derived by quantification of myocardium (area) at risk and infarction, has become a promising surrogate end-point increasingly used in clinical trials testing novel or adjunctive reperfusion strategies. Early post-infarction, the accurate and reproducible quantification of myocardial necrosis, along with the characterization of ischemic myocardial damage in its diverse components, provides important information to predict post-infarction left ventricular (LV) remodeling, being useful for patients stratification and management. Considering its non-invasive nature, cardiac MRI suits well for investigating the time course of infarct healing and the changes occurring in peri-infarcted (adjacent) and remote myocardium, which ultimately promote the geometrical, morphological and functional abnormalities of the entire left ventricle (global LV remodeling). The current review will focus on the cardiac MRI utility for a comprehensive evaluation of patients with acute and chronic IHD with particular regard to post-infarction remodeling. PMID:24282705

  1. Human Placenta-Derived Multipotent Cells (hPDMCs) Modulate Cardiac Injury: From Bench to Small and Large Animal Myocardial Ischemia Studies.

    Science.gov (United States)

    Liu, Yuan-Hung; Peng, Kai-Yen; Chiu, Yu-Wei; Ho, Yi-Lwun; Wang, Yao-Horng; Shun, Chia-Tung; Huang, Shih-Yun; Lin, Yi-Shuan; de Vries, Antoine A F; Pijnappels, Daniël A; Lee, Nan-Ting; Yen, B Linju; Yen, Men-Luh

    2015-01-01

    Cardiovascular disease is the leading cause of death globally, and stem cell therapy remains one of the most promising strategies for regeneration or repair of the damaged heart. We report that human placenta-derived multipotent cells (hPDMCs) can modulate cardiac injury in small and large animal models of myocardial ischemia (MI) and elucidate the mechanisms involved. We found that hPDMCs can undergo in vitro cardiomyogenic differentiation when cocultured with mouse neonatal cardiomyocytes. Moreover, hPDMCs exert strong proangiogenic responses in vitro toward human endothelial cells mediated by secretion of hepatocyte growth factor, growth-regulated oncogene-α, and interleukin-8. To test the in vivo relevance of these results, small and large animal models of acute MI were induced in mice and minipigs, respectively, by permanent left anterior descending (LAD) artery ligation, followed by hPDMC or culture medium-only implantation with follow-up for up to 8 weeks. Transplantation of hPDMCs into mouse heart post-acute MI induction improved left ventricular function, with significantly enhanced vascularity in the cell-treated group. Furthermore, in minipigs post-acute MI induction, hPDMC transplantation significantly improved myocardial contractility compared to the control group (p = 0.016) at 8 weeks postinjury. In addition, tissue analysis confirmed that hPDMC transplantation induced increased vascularity, cardiomyogenic differentiation, and antiapoptotic effects. Our findings offer evidence that hPDMCs can modulate cardiac injury in both small and large animal models, possibly through proangiogenesis, cardiomyogenesis, and suppression of cardiomyocyte apoptosis. Our study offers mechanistic insights and preclinical evidence on using hPDMCs as a therapeutic strategy to treat severe cardiovascular diseases.

  2. The effect of cyclosporin-A on peri-operative myocardial injury in adult patients undergoing coronary artery bypass graft surgery: a randomised controlled clinical trial

    Science.gov (United States)

    Hausenloy, DJ; Kunst, G; Boston-Griffiths, E; Kolvekar, S; Chaubey, S; John, L; Desai, J; Yellon, DM

    2014-01-01

    Objective Cyclosporin-A (CsA) has been reported to reduce myocardial infarct size in both the experimental and clinical settings. This protective effect is dependent on its ability to prevent the opening of the mitochondrial permeability transition pore, a critical determinant of cell death in the setting of acute ischaemia-reperfusion injury. Whether CsA can reduce the extent of peri-operative myocardial injury (PMI) in patients undergoing coronary artery bypass graft (CABG) surgery is unknown, and is investigated in this randomised controlled clinical trial. Methods 78 adult patients undergoing elective CABG surgery were randomised to receive either an intravenous bolus of CsA (2.5 mg/kg) or placebo administered after induction of anaesthesia and prior to sternotomy. PMI was assessed by measuring serum cardiac enzymes, troponin T (cTnT) and CK-MB at 0, 6, 12, 24, 48 and 72 h after surgery. Results There was no significant difference in mean peak cTnT levels between control (n=43) and CsA treatment (n=40) patients (0.56±0.06 ng/mL with control vs 0.35±0.05 ng/mL with CsA; p=0.07). However, in higher-risk patients with longer cardiopulmonary bypass times, there was a significant reduction in PMI with CsA therapy (p=0.049), with a reduced postoperative cTnT rise by 0.03 ng/mL for every 10 min, when compared with control. Conclusions In patients with longer cardiopulmonary bypass times, a single intravenous bolus of CsA administered prior to CABG surgery reduced the extent of PMI. PMID:24488610

  3. The Protective Effect of Apigenin on Myocardial Injury in Diabetic Rats mediating Activation of the PPAR-γ Pathway

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    Umesh B. Mahajan

    2017-04-01

    Full Text Available We substantiated the role of peroxisome proliferator-activated receptor-γ (PPAR-γ activation in the protective effect of apigenin against the myocardial infarction (MI in diabetic rats. Diabetes was induced by intraperitoneal administration of a single dose of streptozotocin (55 mg/kg. The study groups included diabetic rats receiving vehicle, apigenin (75 mg/kg/day, orally, GW9662 (1 mg/kg/day, intraperitoneally, and a combination of apigenin and GW9662 for 14 days. The MI was induced in all the study groups except the diabetic control group by subcutaneous injection of 100 mg/kg/day of isoproterenol on the two terminal days. The diabetes and isoproterenol-induced MI was evident as a reduction in the maximal positive and negative rate of developed left ventricular pressure and an increase in the left ventricular end-diastolic pressure. The activities of creatine kinase on myocardial bundle (CK-MB and lactate dehydrogenase (LDH were also reduced. Apigenin treatment prevented the hemodynamic perturbations, restored the left ventricular function and reinstated a balanced redox status. It protected rats against an MI by attenuating myonecrosis, edema, cell death, and oxidative stress. GW9662, a PPAR-γ antagonist reversed the myocardial protection conferred by apigenin. Further, an increase in the PPAR-γ expression in the myocardium of the rats receiving apigenin reinforces the role of PPAR-γ pathway activation in the cardioprotective effects of apigenin.

  4. Research on Traditional Chinese Medicine in Treaof the present myocardial ischemia-reperfusion injury%中医药对心肌缺血再灌注损伤的研究现状

    Institute of Scientific and Technical Information of China (English)

    赵珏; 吴少俊; 王卫星

    2014-01-01

    Acute coronary syndrome was coronary heart disease in acute onset , clinical types of acute myocardial ischemic injury .In recent years, with thrombolytic therapy and percutaneous coronary intervention technology the establishment and promotion of artery bypass surgery and other methods significantly reduced the myocardial cell death due to ischemia and the ischemia myocardium after restoring blood flow myocardial ischemia-reperfusion injury in a cause for concern .This article analyzed injury mechanism and clinical research mainly from medical intervention to myocardial ischemia reperfusion .%急性冠脉综合征是冠心病中急性发病的临床类型,造成心肌急性缺血性损伤。近年来,随着溶栓疗法、经皮冠状动脉介入技术( Percutaneous coronary intervention ,PCI)、动脉搭桥术等方法的建立和推广,明显的减少了心肌由于缺血导致的细胞坏死,但缺血心肌恢复血流后,出现的心肌缺血再灌注损伤已成关注重点。本文主要从中医药对心肌缺血再灌注损伤干预机制及相关的临床研究进行阐述。

  5. Combined postconditioning with ischemia and α7nAChR agonist produces an enhanced protection against rat myocardial ischemia reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    XIONG Jun; YUAN Yu-jing; XUE Fu-shan; WANG Qiang; LI Shan; LIAO Xu; LIU Jian-hua; CHEN Yi; LI Rui-ping

    2012-01-01

    Background Inflammation is one of important mechanisms for myocardial ischemia reperfusion injury (IRI).Ischemia postconditioning (IPOC) can protect the heart against IRI by inhibiting inflammation,but its cardioprotection is weaker than that of ischemia preconditioning.Recently,the α7 subunit-containing nicotinic acetylcholine receptor (α7nAChR) agonist has shown anti-infiammatory effects in many diseases related to inflammation.This randomized controlled experiment was designed to evaluate whether combined postconditioning with IPOC and the α7nAChR agonist could produce an enhanced cardioprotection in a rat in vivo model of acute myocardial IRI.Methods Fifty Sprague-Dawley rats were randomly divided into five equal groups:sham group,control group,IPOC group,α7nAChR agonist postconditioning group (APOC group) and combined postconditioning with IPOC and α7nAChR agonist group (combined group).Hemodynamic parameters were recorded during the periods of ischemia and reperfusion.Serum concentrations of troponin I (Tnl),tumor necrosis factor α (TNF-α) and high-mobility group box 1 (HMGB-1) at 180 minutes after reperfusion were assayed in all groups.At the end of the experiment,the infarct size was assessed from excised hearts by Evans blue and triphenyl tetrazolium chloride staining.Results As compared to the sham group,the infarct size in the other four groups was significantly increased,serum levels of Tnl,TNF-α and HMGB1 in the control group and TNF-α,HMGB1 in the IPOC group were significantly increased.The infarct size and serum concentrations of TNF-α,HMGB1 and Tnl in the IPOC,APOC and combined groups were significantly lower than those in the control group.As compared to the IPOC group,the infarct size in the combined group was significantly decreased,serum concentrations of Tnl,TNF-α and HMGB1 in the APOC and combined groups were significantly reduced.Although the infarct size was significantly smaller in the combined group than in the APOC group

  6. Loss of ATP-Sensitive Potassium Channel Surface Expression in Heart Failure Underlies Dysregulation of Action Potential Duration and Myocardial Vulnerability to Injury.

    Directory of Open Access Journals (Sweden)

    Zhan Gao

    Full Text Available The search for new approaches to treatment and prevention of heart failure is a major challenge in medicine. The adenosine triphosphate-sensitive potassium (KATP channel has been long associated with the ability to preserve myocardial function and viability under stress. High surface expression of membrane KATP channels ensures a rapid energy-sparing reduction in action potential duration (APD in response to metabolic challenges, while cellular signaling that reduces surface KATP channel expression blunts APD shortening, thus sacrificing energetic efficiency in exchange for greater cellular calcium entry and increased contractile force. In healthy hearts, calcium/calmodulin-dependent protein kinase II (CaMKII phosphorylates the Kir6.2 KATP channel subunit initiating a cascade responsible for KATP channel endocytosis. Here, activation of CaMKII in a transaortic banding (TAB model of heart failure is coupled with a 35-40% reduction in surface expression of KATP channels compared to hearts from sham-operated mice. Linkage between KATP channel expression and CaMKII is verified in isolated cardiomyocytes in which activation of CaMKII results in downregulation of KATP channel current. Accordingly, shortening of monophasic APD is slowed in response to hypoxia or heart rate acceleration in failing compared to non-failing hearts, a phenomenon previously shown to result in significant increases in oxygen consumption. Even in the absence of coronary artery disease, failing myocardium can be further injured by ischemia due to a mismatch between metabolic supply and demand. Ischemia-reperfusion injury, following ischemic preconditioning, is diminished in hearts with CaMKII inhibition compared to wild-type hearts and this advantage is largely eliminated when myocardial KATP channel expression is absent, supporting that the myocardial protective benefit of CaMKII inhibition in heart failure may be substantially mediated by KATP channels. Recognition of Ca

  7. Tumor ablation with irreversible electroporation.

    Directory of Open Access Journals (Sweden)

    Bassim Al-Sakere

    Full Text Available We report the first successful use of irreversible electroporation for the minimally invasive treatment of aggressive cutaneous tumors implanted in mice. Irreversible electroporation is a newly developed non-thermal tissue ablation technique in which certain short duration electrical fields are used to permanently permeabilize the cell membrane, presumably through the formation of nanoscale defects in the cell membrane. Mathematical models of the electrical and thermal fields that develop during the application of the pulses were used to design an efficient treatment protocol with minimal heating of the tissue. Tumor regression was confirmed by histological studies which also revealed that it occurred as a direct result of irreversible cell membrane permeabilization. Parametric studies show that the successful outcome of the procedure is related to the applied electric field strength, the total pulse duration as well as the temporal mode of delivery of the pulses. Our best results were obtained using plate electrodes to deliver across the tumor 80 pulses of 100 micros at 0.3 Hz with an electrical field magnitude of 2500 V/cm. These conditions induced complete regression in 12 out of 13 treated tumors, (92%, in the absence of tissue heating. Irreversible electroporation is thus a new effective modality for non-thermal tumor ablation.

  8. Activation of Na(+)-K(+)-ATPase with DRm217 attenuates oxidative stress-induced myocardial cell injury via closing Na(+)-K(+)-ATPase/Src/Ros amplifier.

    Science.gov (United States)

    Yan, Xiaofei; Xun, Meng; Dou, Xiaojuan; Wu, Litao; Zhang, Fujun; Zheng, Jin

    2017-04-01

    Reduced Na(+)-K(+)-ATPase activity has close relationship with cardiomyocyte death. Reactive oxygen species (ROS) also plays an important role in cardiac cell damage. It has been proved that Na(+)-K(+)-ATPase and ROS form a feed-forward amplifier. The aim of this study was to explore whether DRm217, a proved Na(+)/K(+)-ATPase's DR-region specific monoclonal antibody and direct activator, could disrupt Na(+)-K(+)-ATPase/ROS amplifier and protect cardiac cells from ROS-induced injury. We found that DRm217 protected myocardial cells against hydrogen peroxide (H2O2)-induced cardiac cell injury and mitochondrial dysfunction. DRm217 also alleviated the effect of H2O2 on inhibition of Na(+)-K(+)-ATPase activity, Na(+)-K(+)-ATPase cell surface expression, and Src phosphorylation. H2O2-treatment increased intracellular ROS, mitochondrial ROS and induced intracellular Ca(2+), mitochondrial Ca(2+) overload. DRm217 closed Na(+)-K(+)-ATPase/ROS amplifier, alleviated Ca(2+) accumulation and finally inhibited ROS and mitochondrial ROS generation. These novel results may help us to understand the important role of the Na(+)-K(+)-ATPase in oxidative stress and oxidative stress-related disease.

  9. Use of thallium 201 myocardial imaging to exclude myocardial infarction after dissection in congenital coarctation of the aorta

    Energy Technology Data Exchange (ETDEWEB)

    Halon, D.A.; Weiss, A.T.; Tzivoni, D.; Atlan, H.; Gotsman, M.S.

    1981-10-01

    The use of a mobile gamma camera with thallium 201 myocardial imaging is described to exclude myocardial infarction in a patient admitted to the coronary care unit in shock and with clinical, enzyme, and ECG changes consistent with infarction. The patient suffered from acute aortic dissection associated with congenital coarctation of the aorta. The myocardial scan excluded transmural myocardial injury.

  10. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    NARCIS (Netherlands)

    Smeding, Lonneke; Plotz, Frans B.; Lamberts, Regis R.; van der Laarse, Willem J.; Kneyber, Martin C. J.; Groeneveld, A. B. Johan

    2012-01-01

    Background: Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investiga

  11. Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis

    NARCIS (Netherlands)

    Smeding, Lonneke; Plotz, Frans B.; Lamberts, Regis R.; van der Laarse, Willem J.; Kneyber, Martin C. J.; Groeneveld, A. B. Johan

    2012-01-01

    Background: Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investiga

  12. Function of Heat Shock Protein 70 in Myocardial Ischemia-Reperfusion Injury%热休克蛋白70在心肌缺血/再灌注损伤中的作用

    Institute of Scientific and Technical Information of China (English)

    高奎乐

    2012-01-01

    Ischemia-reperfusion injury is an important cause of myocardial injury during cardiac surgery under cardiopulmonary bypass. Heat shock protein 70 is an important endogenous protective factor,which enhances cell damage tolerance of ischemia-reperfusion injury,maintaining the normal function of the cell metabolism,and improving cell survival. It also plays an important role in the anti-arrhythmia and myocardial anti-oxidative process. Heat shock protein 70 has an endogenous protective effect on myocardial in ischemia-reperfusion injury.%缺血/再灌注损伤是体外循环下心脏手术中心肌损伤的重要原因.热休克蛋白70是一种重要的内源性保护因子,它在缺血/再灌注损伤过程中增强细胞对损害的耐受程度,维持细胞的正常功能代谢,提高细胞生存率,在抗心律失常及心肌抗氧化过程中也起到重要作用.热休克蛋白70对缺血/再灌注损伤心肌具有内源性保护作用.

  13. Clinical Analysis of 113 Caes of Upper Gastrointestinal Bleeding with Ischemic Myocardial Injury%上消化道出血伴发缺血性心肌损伤113例临床分析

    Institute of Scientific and Technical Information of China (English)

    文玉; 李晓燕; 罗娟; 戴薇; 张磊

    2011-01-01

    Objective To investigate the pathogenesis, clinical manifestations, relevant examinations,treatments and prognosis of ischemic myocardial injury (IMI) with upper gastrointestinal bleeding (UGIB).Method We restropectively analyzed the clinical data of 113 cases of ischemic myocardial injury (IMI) with upper gastrointestinal bleeding (UGIB).Results 66 inpatients had no typical performance of myocardial injury (58.40%) , 97 inpatients was getting better and discharged from hospital (85.84%) , 16 inpatients died (14.16%).Conclusions The clinical manifestations of patients who have ischemic myocardial injury (IMI) with upper gastrointestinal bleeding (UGIB) are atypical.Under these conditions, IMI is easily overlooked.Therefore, to find revelant manifestations of atypical IMI in time has significance in treating IMI with upper gastrointestinal bleeding (UGIB).%目的 探讨上消化道出血(upper gastrointestinal bleeding,UGIB)伴发缺血性心肌损伤(ischemicmyocardial injury,IMI)的发病机制、临床表现、相关检查、治疗及预后.方法 回顾性分析上消化道出血伴发缺血性心肌损伤113例.结果 113例中66例(58.40%)无典型心肌损伤临床表现,病情好转出院97例(85.84%),死亡16例(14.16%).结论 当上消化道出血与缺血性心肌损伤并存时,心肌损伤的表现往往不典型而易被忽视,因此及时发现不典型心肌损伤的相关表现,对于正确处理上消化道出血与心肌损伤具有重要的意义.

  14. Effect of intravenous FX06 as an adjunct to primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction results of the F.I.R.E. (Efficacy of FX06 in the Prevention of Myocardial Reperfusion Injury) trial

    DEFF Research Database (Denmark)

    Atar, Dan; Petzelbauer, Peter; Schwitter, Jürg

    2009-01-01

    by mitigating reperfusion injury. METHODS: In all, 234 patients presenting with acute ST-segment elevation myocardial infarction were randomized in 26 centers. FX06 or matching placebo was given as intravenous bolus at reperfusion. Infarct size was assessed 5 days after myocardial infarction by late gadolinium...... enhanced cardiac magnetic resonance imaging. Secondary outcomes included size of necrotic core zone and microvascular obstruction at 5 days, infarct size at 4 months, left ventricular function, troponin I levels, and safety. RESULTS: There were no baseline differences between groups. On day 5......: In this proof-of-concept trial, FX06 reduced the necrotic core zone as one measure of infarct size on magnetic resonance imaging, while total late enhancement was not significantly different between groups. The drug appears safe and well tolerated. (Efficacy of FX06 in the Prevention of Myocardial Reperfusion...

  15. 厄多司坦预处理对大鼠心肌缺血再灌注损伤及心肌细胞凋亡的影响%Effects of erdosteine preconditioning on myocardial ischemia-reperfusion injury and myocardial apoptosis in rats

    Institute of Scientific and Technical Information of China (English)

    王洪波; 汪斌; 向小勇

    2011-01-01

    Objective To investigate the effects of erdosteine preconditioning on myocardial ischemiareperfusion injury and myocardial apoptosis in rats. Methods Thirty male SD rats were randomly and evenly divided into three groups, i. e. , sham operation group, ischemia-reperfusion group, and erdosteine preconditioning group. The left anterior descending coronary artery was ligated for 30 min, followed by 120 min of reperfusion to establish the mt model of myocardial ischemia-reperfusion injury. The contents of serum and myocardial malondialdehyde (MDA), the activities of serum and myocardial superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), as well as the activities of serum creatine kinase (CK) and lactate dehydrogenase (LDH) were detected at the end of reperfusion. TUNEL was used to detect the myocardial apoptosis index. Results Erdosteine preconditioning significantly reduced the contents of serum and myocardial MDA ( P < 0.05 ), lowered the activities of serum CK and LDH ( P < 0.05, P < 0.01 ), enhanced the activities of serum and myocardial SOD, GSH-Px and CAT (P <0.05, P <0.01 ), and decreased the myocardial apoptosis index (P < 0.05 ). Conclusion Erdosteine has preventive effects on myocardial ischemiareperfusion injury in rats and can alleviate myocardial apoptosis induced by oxygen free radicals.%目的 探讨厄多司坦预处理对大鼠心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury,MIRI)的保护作用及对心肌细胞凋亡的影响.方法 雄性SD大鼠30只,完全随机设计法分成伪手术组、缺血再灌注组及厄多司坦预处理组,每组10只.采用结扎左冠状动脉前降支30 min、再灌注120 min的方法建立大鼠心肌缺血再灌注损伤模型.再灌注末,测定血清丙二醛(MDA)含量,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化酶(GSH-Px)、肌酸激酶(CK)、乳酸脱氢酶(LDH)的活性;心肌MDA含量,SOD、CAT、GSH-Px的活性;TUNEL

  16. Myocardial infarction worsens glomerular injury and microalbuminuria in rats with pre-existing renal impairment accompanied by the activation of ER stress and inflammation.

    Science.gov (United States)

    Dong, Zhifeng; Wu, Penglong; Li, Yongguang; Shen, Yuan; Xin, Ping; Li, Shuai; Wang, Zhihua; Dai, Xiaoyan; Zhu, Wei; Wei, Meng

    2014-12-01

    Deterioration of renal function occurs after chronic heart failure in approximately one-third of patients, particularly in those with pre-existing renal impairment such as diabetic nephropathy. Impaired renal function in these patients is always associated with a worse prognosis. However, the mechanisms underlying such deterioration of renal function are still largely unknown. In three separate protocols, we compared 1) sham operation (Ctr, n = 10) with surgically induced myocardial infarction (MI, n = 10); 2) unilateral nephrectomy (UNX, n = 10) with UNX + MI (n = 10); and 3) STZ-induced type 1 diabetes (DB, n = 10) with DB + MI (n = 10). The differences between combined injury models (UNX + MI, DB + MI) and simple MI were also examined. Renal remodeling, function, ER stress (CHOP and GRP78) and inflammation (infiltration of inflammatory cells, NF-κB p65) were evaluated 12 weeks after MI. In common SD rats, MI activated less glomerular ER stress and inflammation, resulting in a minor change of glomerular remodeling and microalbuminuria. However, MI significantly increased the glomerular expression of GRP78 and CHOP in UNX and DB rats. In addition, it also promoted the infiltration of CD4+ T cells, particularly inflammatory cytokine (IFN-γ, IL-17, IL-4)-producing CD4+ T cells, and the expression of NF-κB p65 in the glomeruli. By contrast, significant glomerular fibrosis, glomerulosclerosis, podocyte injury and microalbuminuria were found in rats with UNX + MI and DB + MI. MI significantly increased chronic glomerular injury and microalbuminuria at 12 weeks in rats with pre-existing renal impairment, i.e., UNX and DB, but not common SD rats. These changes were accompanied by increased glomerular ER stress and immune-associated inflammation.

  17. Effect of short-term high-dose atorvastatin on systemic inflammatory response and myocardial ischemic injury in patients with unstable angina pectoris undergoing percutaneous coronary intervention

    Institute of Scientific and Technical Information of China (English)

    Sun Fei; Yin Zhao; Shi Quanxing; Zhao Bei; Wang Shouli

    2014-01-01

    Background Percutaneous coronary intervention (PCI) could develop periprocedural myocardial infarction and inflammatory response and statins can modify inflammatory responses property.The aim of this study was to evaluate whether short-term high-dose atorvastatin therapy can reduce inflammatory response and myocardial ischemic injury elicited by PCI.Methods From March 2012 to May 2014,one hundred and sixty-five statin-naive patients with unstable angina referred for PCI at Department of Cardiology of the 306th Hospital,were enrolled and randomized to 7-day pretreatment with atorvastatin 80 mg/d as high dose group (HD group,n=56) or 20 mg/d as normal dose group (ND group,n=57) or an additional single high loading dose (80 mg) followed 6-day atorvastatin 20 mg/d as loading dose group (LD group,n=52).Plasma C-reactive protein (CRP) and interleukin-6 (IL-6) levels were determined before intervention and at 5 minutes,24 hours,48 hours,72 hours,and 7 days after intervention.Creatine kinase-myocardial isoenzyme (CK-MB) and cardiac troponin I (cTnl) were measured at baseline and then 24 hours following PCI.Results Plasma CRP and IL-6 levels increased from baseline after PCI in all groups.CRP reached a maximum at 48 hours and IL-6 level reached a maximum at 24 hours after PCI.Plasma CRP levels at 24 hours after PCI were significantly lower in the HD group ((9.14±3.02) mg/L) than in the LD group ((11.06±3.06) mg/L) and ND group ((12.36±3.08) mg/L,P <0.01); this effect persisted for 72 hours.IL-6 levels at 24 hours and 48 hours showed a statistically significant decrease in the HD group ((16.19±5.39) ng/L and (14.26±4.12) ng/L,respectively)) than in the LD group ((19.26±6.34) ng/L and (16.03±4.08) ng/L,respectively,both P <0.05) and ND group ((22.24±6.98) ng/L and (17.24±4.84) ng/L,respectively).IL-6 levels at 72 hours and 7 days showed no statistically significant difference among the study groups.Although PCI caused a significant increase in CK-MB and cTnl at

  18. Research Progression of Action Targets in Myocardial Ischemia/reperfusion Injury Antagonists%抗心肌缺血/再灌注药物作用靶点的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘明洁

    2014-01-01

    This review focuses on cardioprotection effects and underlying mechanisms of myocardial ischemia/reperfusion injury antagonists on myocardial norepinephrine, dopamine, opioid and adenosine receptors. The drugs used against re-perfusion injury are able to attenuate calcium overload, scavenge oxygen free radicals, decrease inflammatory cytokines, lessen cardiomyocytes apotosis and myocardial necrosis, and minimize ischemia or infarct size after myocardial ischemia/reperfusion. To better searching and developing novel agents of myocardial protection, and diminishing incidence and long-term mortality of reperfusion injury of patient heart resulted from revascularization treatments of thrombolysis, percutaneous transluminal coronary angioplasty and coronary artery bypass grafting, and makes a contribution.%本文回顾了抗心肌缺血/再灌注损伤药物作用于心肌肾上腺素、多巴胺、阿片、腺苷等靶点所产生的心肌保护作用及潜在机理。抗心肌缺血/再灌注损伤药物能减轻钙超载、清除氧自由基、减少致炎因子、减弱心肌细胞凋亡和心肌缺血或梗死面积。为更好寻找和开发新型心肌保护药物,减少病患心肌缺血后行溶栓、经皮冠状动脉腔内血管成形术(PTCA)、冠状动脉旁路移植术(CABG)等血管重建疗法所引起的再灌注损伤的发生率及远期病死率做出贡献。

  19. Thermodynamics of irreversible physicochemical processes

    Science.gov (United States)

    Bulatov, N. K.; Lundin, A. B.

    The main principles of the phenomenological thermodynamics of irreversible processes are expounded in close relation to concepts of classical phenomenological thermodynamics, and the most important thermodynamic equations of state are presented. These principles are then used in describing various physicochemical processes, including chemical transformations, structural relaxation, heat conduction, electrical conductivity, diffusion, and sedimentation in homogeneous, continuous, and discontinuous systems. Other processes discussed include filtration, electrical osmosis, heat transfer, and the mechanocaloric effect.

  20. Irreversible stochastic processes on lattices

    Energy Technology Data Exchange (ETDEWEB)

    Nord, R.S.

    1986-01-01

    Models for irreversible random or cooperative filling of lattices are required to describe many processes in chemistry and physics. Since the filling is assumed to be irreversible, even the stationary, saturation state is not in equilibrium. The kinetics and statistics of these processes are described by recasting the master equations in infinite hierarchical form. Solutions can be obtained by implementing various techniques: refinements in these solution techniques are presented. Programs considered include random dimer, trimer, and tetramer filling of 2D lattices, random dimer filling of a cubic lattice, competitive filling of two or more species, and the effect of a random distribution of inactive sites on the filling. Also considered is monomer filling of a linear lattice with nearest neighbor cooperative effects and solve for the exact cluster-size distribution for cluster sizes up to the asymptotic regime. Additionally, a technique is developed to directly determine the asymptotic properties of the cluster size distribution. Finally cluster growth is considered via irreversible aggregation involving random walkers. In particular, explicit results are provided for the large-lattice-size asymptotic behavior of trapping probabilities and average walk lengths for a single walker on a lattice with multiple traps. Procedures for exact calculation of these quantities on finite lattices are also developed.

  1. A Translational Study of a New Therapeutic Approach for Acute Myocardial Infarction: Nanoparticle-Mediated Delivery of Pitavastatin into Reperfused Myocardium Reduces Ischemia-Reperfusion Injury in a Preclinical Porcine Model

    Science.gov (United States)

    Ichimura, Kenzo; Matoba, Tetsuya; Nakano, Kaku; Tokutome, Masaki; Honda, Katsuya; Koga, Jun-ichiro; Egashira, Kensuke

    2016-01-01

    Background There is an unmet need to develop an innovative cardioprotective modality for acute myocardial infarction, for which interventional reperfusion therapy is hampered by ischemia-reperfusion (IR) injury. We recently reported that bioabsorbable poly(lactic acid/glycolic acid) (PLGA) nanoparticle-mediated treatment with pitavastatin (pitavastatin-NP) exerts a cardioprotective effect in a rat IR injury model by activating the PI3K-Akt pathway and inhibiting inflammation. To obtain preclinical proof-of-concept evidence, in this study, we examined the effect of pitavastatin-NP on myocardial IR injury in conscious and anesthetized pig models. Methods and Results Eighty-four Bama mini-pigs were surgically implanted with a pneumatic cuff occluder at the left circumflex coronary artery (LCx) and telemetry transmitters to continuously monitor electrocardiogram as well as to monitor arterial blood pressure and heart rate. The LCx was occluded for 60 minutes, followed by 24 hours of reperfusion under conscious conditions. Intravenous administration of pitavastatin-NP containing ≥ 8 mg/body of pitavastatin 5 minutes before reperfusion significantly reduced infarct size; by contrast, pitavastatin alone (8 mg/body) showed no therapeutic effects. Pitavastatin-NP produced anti-apoptotic effects on cultured cardiomyocytes in vitro. Cardiac magnetic resonance imaging performed 4 weeks after IR injury revealed that pitavastatin-NP reduced the extent of left ventricle remodeling. Importantly, pitavastatin-NP exerted no significant effects on blood pressure, heart rate, or serum biochemistry. Exploratory examinations in anesthetized pigs showed pharmacokinetic analysis and the effects of pitavastatin-NP on no-reflow phenomenon. Conclusions NP-mediated delivery of pitavastatin to IR-injured myocardium exerts cardioprotective effects on IR injury without apparent adverse side effects in a preclinical conscious pig model. Thus, pitavastatin-NP represents a novel therapeutic

  2. Molecular and biochemical evidence on the protective effects of quercetin in isoproterenol-induced acute myocardial injury in rats.

    Science.gov (United States)

    Kumar, Mukesh; Kasala, Eshvendar Reddy; Bodduluru, Lakshmi Narendra; Kumar, Vikas; Lahkar, Mangala

    2017-01-01

    Cardioprotection represents one of the most important and realistic aspects of preventive therapy today. Quercetin, a naturally occurring dietary flavone, has been studied extensively for its antioxidant properties. The objective of present study is to find out the cardioprotective activity and to explore the underlying mechanisms of quercetin pretreatment (50 mg/kg body weight, orally) for 14 days against isoproterenol (ISO; 100 mg/kg body weight, subcutaneously) induced myocardial infarction in Wistar rats. Cardiac diagnostic markers, oxidative stress, inflammatory cytokines, histopathology along with gene expression analysis of calpain 1 and 2 were carried out in experimental rats. Quercetin pretreatment showed protective effects on heart by significantly attenuating the ISO-induced oxidative stress, inflammation, protecting heart architecture, and by downregulation of the expression of calpain. Overall, these findings revealed the cardio-protective potential of quercetin and its mechanism of action against ISO-induced MI in rats.

  3. Comparison of the impact of prolonged low-pressure and standard-pressure pneumoperitoneum on myocardial injury after robot-assisted surgery in the Trendelenburg position: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Zhang, Xixue; Wei, Jionglin; Song, Xiaoxing; Zhang, Yuhao; Qian, Weiqing; Sheng, Lu; Shen, Zhoujun; Yang, Lvjun; Dong, Rong; Gu, Weidong

    2016-10-10

    Robot-assisted laparoscopic radical prostatectomy and robot-assisted radical cystectomy have gradually become the preferred choices for urologists as they allow surgeons to perform complex procedures more precisely and effectively. The pneumoperitoneum, which is normally applied in these surgeries to provide visual clarity and space to perform the procedure, may cause hemodynamic disturbance, potentially myocardial injury. Thus surgeons have recently considered opting for the low-pressure pneumoperitoneum to lower this negative impact. Herein we describe a protocol for a clinical trial to compare the impact of prolonged low-pressure and standard-pressure pneumoperitoneum on myocardial injury after robot-assisted surgery. This study is designed to be a bicenter clinical trial. In total 280 patients scheduled to undergo robot-assisted laparoscopic radical prostatectomy or robot-assisted radical cystectomy will be enrolled and randomized into two groups, with standard- (12-16 mmHg) and low-pressure (7-10 mmHg) pneumoperitoneum, respectively. Troponin T will be measured as the primary endpoint to assess the extent of myocardial injury. Nt-proBNP and hemodynamic indexes will also be recorded for further analysis. The significance of this study is emphasized by the fact that there are few studies that have focused on the impact of prolonged pneumoperitoneum on myocardial injury, which is relevant to postoperative mortality. We hope that the conclusions drawn from this study could provide reference and basis to the future of the pneumoperitoneum in clinical practice. Registered at https://www.clinicaltrials.gov with the Identifier NCT02600481 on November 5, 2015.

  4. 生酮饮食对兔心肌缺血再灌注损伤的保护%Protective Function of KD on Myocardial Ischemia-reperfusion Injury in Rabbit

    Institute of Scientific and Technical Information of China (English)

    刘志强; 崔利德

    2011-01-01

    目的 探讨生酮饮食(KD)对兔心肌缺血再灌注损伤影响.方法 分别给予雄性兔正常饮食(normal diet,ND)和KD6周后,结扎免冠状动脉左前降支30 min后,恢复再灌注180 min,通过观察心电图、心肌酶学和心肌梗死范围指标,评价KD对兔心肌缺血再灌注损伤的保护作用.结果 A组(ND+假手术组)乳酸脱氢酸、肌酸激酶活力未升高,心电图无变化,心肌无梗死.B组(ND+缺血再灌注组)变化明显.C组(KD+缺血再灌注组)较B组轻.结论 用KD干预后,兔心肌缺血再灌注损伤减轻.%[Objective]To discuss the effect of Ketogenic diet ( KD ) on myocardial ischemia-reperfusion injury in rabbit.[Methods]After pretreatment normal diet (ND) and KD respectively in male rabbits for 6 weeks, all the rabbits were ligated with the left anterior descending coronary arteries for 30 min and then recovered reperfusion for 180 min.The protection of KD on myocardial ischemia-reperfusion injury was evaluated by monitoring of ECG and serum creatine kinases, and myocardial infarct size measurements.[Results]In Group A (ND + sham operation) LDH, CK is not elevated, without change in ECG and myocardial infarction.In Group B ( ND + ischemia-reperfusion), the changes were significant.The injury of Group C ( KD + ischemia-reperfusion) was lighter than that of Group B.[Conclusion]KD intervention relives the ischemia-reperfusion injury.

  5. Attenuation of mitochondrial, but not cytosolic, Ca2+ overload reduces myocardial injury induced by ischemia and reperfusion

    Institute of Scientific and Technical Information of China (English)

    Chun-mei CAO; Wing-yee YAN; Jing LIU; Kenneth WL KAM; Shi-zhong ZHAN; James SK SHAM; Tak-ming WONG

    2006-01-01

    Aim: Attenuation of mitochondrial Ca2+ ([Ca2+]m, but not cytosolic Ca2+ ([Ca2+]c), overload improves contractile recovery. We hypothesized that attenuation of [Ca2+]m, but not [Ca2+]c, overload confers cardioprotection against ischemia/ reperfusion-induced injury. Methods: Infarct size from isolated perfused rat heart, cell viability, and electrically-induced Ca2+ transient in isolated rat ventricular myocytes were measured. We determined the effects of BAPTA-AM, a Ca2+ chelator, at concentrations that abolish the overload of both [Ca2+]c and [Ca2+]m, and ruthenium red, an inhibitor of mitochondrial uniporter of Ca2+ transport, at concentrations that abolish the overload of [Ca2+]m, but not [Ca2+]c, on cardiac injury induced by ischemia/reperfusion. Results: Attenuation of both [Ca2+]m and [Ca2+]c by BAPTA-AM, and attenuation of [Ca2+]m, but not [Ca2+]c, overload by ruthenium red, reduced the cardiac injury observations, indicating the importance of [Ca2+]m in cardioprotection and contractile recovery in response to ischemia/reperfusion. Conclusion: The study has provided unequivocal evidence using a cause-effect approach that attenuation of [Ca2+]m, but not [Ca2+]c, overload is responsible for cardioprotection against ischemia/reperfusion-induced injury. We also confirmed the previous observation that attenuation of [Ca2+]m, but not [Ca2+]c, by ruthenium red improves contractile recovery following ischemia/ reperfusion.

  6. Rat experimental model of myocardial ischemia/reperfusion injury: an ethical approach to set up the analgesic management of acute post-surgical pain.

    Directory of Open Access Journals (Sweden)

    Maria Chiara Ciuffreda

    Full Text Available RATIONALE: During the past 30 years, myocardial ischemia/reperfusion injury in rodents became one of the most commonly used model in cardiovascular research. Appropriate pain-prevention appears critical since it may influence the outcome and the results obtained with this model. However, there are no proper guidelines for pain management in rats undergoing thoracic surgery. Accordingly, we evaluated three analgesic regimens in cardiac ischemia/reperfusion injury. This study was strongly focused on 3R's ethic principles, in particular the principle of Reduction. METHODS: Rats undergoing surgery were treated with pre-surgical tramadol (45 mg/kg intra-peritoneal, or carprofen (5 mg/kg sub-cutaneous, or with pre-surgical administration of carprofen followed by 2 post-surgery tramadol injections (multi-modal group. We assessed behavioral signs of pain and made a subjective evaluation of stress and suffering one and two hours after surgery. RESULTS: Multi-modal treatment significantly reduced the number of signs of pain compared to carprofen alone at both the first hour (61±42 vs 123±47; p<0.05 and the second hour (43±21 vs 74±24; p<0.05 post-surgery. Tramadol alone appeared as effective as multi-modal treatment during the first hour, but signs of pain significantly increased one hour later (from 66±72 to 151±86, p<0.05. Carprofen alone was more effective at the second hour post-surgery when signs of pain reduced to 74±24 from 113±40 in the first hour (p<0.05. Stress behaviors during the second hour were observed in only 20% of rats in the multimodal group compared to 75% and 86% in the carprofen and tramadol groups, respectively (p<0.05. CONCLUSIONS: Multi-modal treatment with carprofen and tramadol was more effective in preventing pain during the second hour after surgery compared with both tramadol or carprofen. Our results suggest that the combination of carprofen and tramadol represent the best therapy to prevent animal pain after

  7. Rat experimental model of myocardial ischemia/reperfusion injury: an ethical approach to set up the analgesic management of acute post-surgical pain.

    Science.gov (United States)

    Ciuffreda, Maria Chiara; Tolva, Valerio; Casana, Renato; Gnecchi, Massimiliano; Vanoli, Emilio; Spazzolini, Carla; Roughan, John; Calvillo, Laura

    2014-01-01

    During the past 30 years, myocardial ischemia/reperfusion injury in rodents became one of the most commonly used model in cardiovascular research. Appropriate pain-prevention appears critical since it may influence the outcome and the results obtained with this model. However, there are no proper guidelines for pain management in rats undergoing thoracic surgery. Accordingly, we evaluated three analgesic regimens in cardiac ischemia/reperfusion injury. This study was strongly focused on 3R's ethic principles, in particular the principle of Reduction. Rats undergoing surgery were treated with pre-surgical tramadol (45 mg/kg intra-peritoneal), or carprofen (5 mg/kg sub-cutaneous), or with pre-surgical administration of carprofen followed by 2 post-surgery tramadol injections (multi-modal group). We assessed behavioral signs of pain and made a subjective evaluation of stress and suffering one and two hours after surgery. Multi-modal treatment significantly reduced the number of signs of pain compared to carprofen alone at both the first hour (61±42 vs 123±47; p<0.05) and the second hour (43±21 vs 74±24; p<0.05) post-surgery. Tramadol alone appeared as effective as multi-modal treatment during the first hour, but signs of pain significantly increased one hour later (from 66±72 to 151±86, p<0.05). Carprofen alone was more effective at the second hour post-surgery when signs of pain reduced to 74±24 from 113±40 in the first hour (p<0.05). Stress behaviors during the second hour were observed in only 20% of rats in the multimodal group compared to 75% and 86% in the carprofen and tramadol groups, respectively (p<0.05). Multi-modal treatment with carprofen and tramadol was more effective in preventing pain during the second hour after surgery compared with both tramadol or carprofen. Our results suggest that the combination of carprofen and tramadol represent the best therapy to prevent animal pain after myocardial ischemia/reperfusion. We obtained our results

  8. ATP敏感性钾通道在心肌缺血/再灌注损伤中的作用%Roles of ATPV sensitive Potassium Channels against Myocardial Ischemia/Reperfusion Injury

    Institute of Scientific and Technical Information of China (English)

    李清

    2012-01-01

    心肌缺血/再灌注损伤是缺血性心脏病以及心脏手术后心功能不全的主要病理基础.寻找有效的心肌保护措施减轻心肌缺血/再灌注损伤具有重要意义.各种心肌保护措施,如心脏停搏液、缺血预处理和缺血后处理等成为人们研究的热点.ATP敏感性钾通道在缺血/再灌注心肌损伤的心肌保护策略中发挥了重要作用,是心肌保护的重要作用机制.%Ischemia/reperfusion injury is a major pathophysiologic mechanism leading to myocardial dysfunction after myocardial infarction or cardiac surgery. It is necessary to find effective methods to limit ischemia/reperfusion injury. Many effective methods,such as cardioplegia, ischemia preconditioning and ischemia postconditioning garners are drawing more and more attention. ATP-sensitive potassium channels play important roles in myocardial protection against ischemia/reperfusion injury,which are the important mechanisms for cardio-protection..

  9. 心肌损伤标志物在心肌损伤及梗死中的应用发展%Research progress of myocardial injury markers in myocardial injury and infarction

    Institute of Scientific and Technical Information of China (English)

    李文文

    2013-01-01

    急性心肌梗死(acute myocardial infartion, AMI)的发病率及致死致残率都较高,已成为严重危害人类健康的疾病之一.早期诊断对于提高患者的存活率具有重要价值,测定血中特异标志物是反映心肌损伤的重要手段之一,但AMI发病突然,进程凶险且转归难以预测,若能提前预知事件的发生,实施早期干预,可避免严重后果的发生,目前已有很多风险预测标志物在临床中得到应用.现就心肌损伤及风险指标的发展进程作一综述.

  10. Effects of reperfusion arrhythmias and myocardial connexin 43 by Compound Astragalus Mixture Nourishing Heart in a rat model of acute myocardial ischemic reperfusion injury%复方黄芪养心合剂对大鼠缺血再灌注心肌缝隙连接蛋白43的影响

    Institute of Scientific and Technical Information of China (English)

    陈启兰; 龚一萍; 祝光礼; 齐国安; 赫小龙; 任兴昌; 王骋

    2013-01-01

    目的:观察复方黄芪养心合剂对SD大鼠缺血再灌注心肌细胞缝隙连接蛋白43(Cx43)分布的改变和表达的影响.方法:应用复方黄芪养心合剂按每天14g/kg剂量、琥珀酸美托洛尔缓释片按每天(MSSRT) 9.5mg/kg剂量灌胃2周后,对SD大鼠行冠状动脉左前降支结扎30min后再灌注60min造成心肌缺血再灌注(I/R)损伤模型,记录Ⅱ导联心电图,采用免疫组织化学法(IHC)观察心肌细胞Cx43分布的改变;运用Image Pro Plus 6.0图像分析软件对Cx43的表达进行半定量分析.结果:Cx43平均光密度(AOD)I/R组心肌内膜下缺血区Cx43的AOD显著低于假手术组(P<0.01),且MSSRT组、复方组较1/R组升高(P<0.05).结论:对冠状动脉左前降支结扎术后再灌注SD大鼠,复方黄芪养心合剂对心肌细胞Cx43分布的改变有改善作用,有促进心肌内膜下缺血区域Cx43表达的作用,其作用与MSSRT相近.%Objective: To evaluate the effects of Compound Astragalus Mixture Nourishing Heart (CAMNH) antiarrhythmia and myocardial connexin 43 (Cx43) in a rat model of acute myocardial ischemic reperfusion injury. Methods: Myocardial infarction (MI) was induced by ligating left anterior descending coronary artery (LAD) for 30 minutes, followed by reperfusion of 60 minutes in rats. Rats were treated with CAMNH (14g·kg-1·d-1) or metoprolol succinate sustained-release tablets (MSSRT, 9.5mg·kg-1d-1) for 14 days before MI. The distribution of myocardial Cx43 was observed by Immunohistochemistry (IHC), and the expression of myocardial Cx43, which were represented by average optical density (AOD), was measured by Image Pro Plus 6.0. Results: The expression of myocardial Cx43 in infarction region was significantly reduced, disordered and even all disappearing, the expression of myocardial Cx43 from infarction region into ischemic region and normal region had a gradual recovery of transitional variability. Ischemia/reperfusion(I/R) group vs sham-operated (SO

  11. 脑心综合征患者的心电图及心肌损伤标志物的变化%Change of electrocardiogram and markers of myocardial injury in patients with cerebro-cardiac syndrome.

    Institute of Scientific and Technical Information of China (English)

    李宏治; 张宝成; 钟志越

    2011-01-01

    目的 探讨脑卒中患者发生脑心综合征时,心电图(ECG)与心肌酶谱、肌钙蛋白-T(CTnT)等心肌损伤标志物的变化及意义.方法 检测发生脑心综合征的135例脑卒中患者的ECG、心肌酶谱与CTnT,并对不同损伤部位、不同病种的临床资料进行分析.结果 脑卒中后ECG改变在病后1周内发生率84.4%,其与脑损害部位有关,靠近基底节及丘脑的部位病变时其心电图异常率高;丘脑损伤以早搏多见,延髓损伤以心动过缓多见,而基底节区则以快速型心律失常多见;心肌酶谱异常者CK-MB升高为55.5%,肌钙蛋白T24h内升高者46.7%.结论 脑心综合征表现为早期心电图异常与心肌损伤标志物的升高.%Objective To investigate the change and significance of electrocardiogram( ECG) and markers of myocardi-al injury such as myocardial enzymes and troponin-T (CTnT) in affected patients with cerebrocardiac syndrome ( CCS) caused by cerebral stroke. Methods In one hundred and thirty-five patients with CCS, the ECG, myocardial enzymes and CTnT, and clinical data of different injury parts and different kinds of diseases were analyzed. Results The incidence of ECG changes within 1 week after stroke was 84.4%. The parts of the brain damage were related to the site near the basal ganglia and thalamus lesions of its high rate of abnormal electrocardiogram; Hypothalamic injury was common to premature beats, damage to heart over the medullary bradycardia was more commonly, while the basal ganglia of tachya-rrhythmia; abnormal myocardial enzyme CK-MB increase was in 55. 5% , troponin T 24 hours, increased in 46. 7%. Conclusion Early abnormal electrocardiogram changes and makers of myocardial injury occurs in cerebro-cardiac syndrome.

  12. The role of gasotransmitters NO, H2S and CO in myocardial ischaemia/reperfusion injury and cardioprotection by preconditioning, postconditioning and remote conditioning.

    Science.gov (United States)

    Andreadou, Ioanna; Iliodromitis, Efstathios K; Rassaf, Tienush; Schulz, Rainer; Papapetropoulos, Andreas; Ferdinandy, Péter

    2015-03-01

    Ischaemic heart disease is one of the leading causes of morbidity and mortality worldwide. The development of cardioprotective therapeutic agents remains a partly unmet need and a challenge for both medicine and industry, with significant financial and social implications. Protection of the myocardium can be achieved by mechanical vascular occlusions such as preconditioning (PC), when brief episodes of ischaemia/reperfusion (I/R) are experienced prior to ischaemia; postconditioning (PostC), when the brief episodes are experienced at the immediate onset of reperfusion; and remote conditioning (RC), when the brief episodes are experienced in another vascular territory. The elucidation of the signalling pathways, which underlie the protective effects of PC, PostC and RC, would be expected to reveal novel molecular targets for cardioprotection that could be modulated by pharmacological agents to prevent reperfusion injury. Gasotransmitters including NO, hydrogen sulphide (H2S) and carbon monoxide (CO) are a growing family of regulatory molecules that affect physiological and pathological functions. NO, H2S and CO share several common properties; they are beneficial at low concentrations but hazardous in higher amounts; they relax smooth muscle cells, inhibit apoptosis and exert anti-inflammatory effects. In the cardiovascular system, NO, H2S and CO induce vasorelaxation and promote cardioprotection. In this review article, we summarize current knowledge on the role of the gasotransmitters NO, H2S and CO in myocardial I/R injury and cardioprotection provided by conditioning strategies and highlight future perspectives in cardioprotection by NO, H2S, CO, as well as their donor molecules.

  13. Anti-arrhythmic effect of diosgenin in reperfusion-induced myocardial injury in a rat model: activation of nitric oxide system and mitochondrial KATP channel.

    Science.gov (United States)

    Badalzadeh, Reza; Yousefi, Bahman; Majidinia, Maryam; Ebrahimi, Hadi

    2014-11-01

    This study was designed to investigate the anti-arrhythmic effect of diosgenin preconditioning in myocardial reperfusion injury in rat, focusing on the involvement of the nitric oxide (NO) system and mitochondrial ATP-dependent potassium (mitoKATP) channels in this scenario. After isolation of the hearts of male Wister rats, the study was conducted in an isolated buffer-perfused heart model. Global ischemia (for 30 min) was induced by interruption of the aortic supply, which was followed by 90-min reperfusion. Throughout the experiment, the electrocardiograms of hearts were monitored using three golden surface electrodes connected to a data acquisition system. Arrhythmias were assessed based on the Lambeth convention and were categorized as number, duration and incidence of ventricular tachycardia (VT), ventricular fibrillation (VF), and premature ventricular complexes (PVC), and arrhythmic score. Additionally, lactate dehydrogenase (LDH) levels in coronary effluent were estimated colorimetrically. Diosgenin pre-administration for 20 min before ischemia reduced the LDH release into the coronary effluent, as compared with control hearts (P PVC, VT and VF, a reduced duration and incidence of VT and VF, and less severe arrhythmia at reperfusion phase, in comparison with controls. Blocking the mitoKATP channels using 5-hydroxydecanoate as well as inhibiting the NO system through prior administration of L-NAME significantly reduced the positive effects of diosgenin. Our finding showed that pre-administration of diosgenin could provide cardioprotection through anti-arrhythmic effects against ischemia-reperfusion (I/R) injury in isolated rat hearts. In addition, mitoKATP channels and NO system may be the key players in diosgenin-induced cardioprotective mechanisms.

  14. Olmesartan restores the protective effect of remote ischemic perconditioning against myocardial ischemia/reperfusion injury in spontaneously hypertensive rats.

    Science.gov (United States)

    Lu, Xin; Bi, Yan-Wen; Chen, Ke-Biao

    2015-07-01

    Remote ischemic perconditioning is the newest technique used to lessen ischemia/reperfusion injury. However, its effect in hypertensive animals has not been investigated. This study aimed to examine the effect of remote ischemic perconditioning in spontaneously hypertensive rats and determine whether chronic treatment with Olmesartan could influence the effect of remote ischemic perconditioning. Sixty rats were randomly divided into six groups: vehicle-sham, vehicle-ischemia/reperfusion injury, vehicle-remote ischemic perconditioning, olmesartan-sham, olmesartan-ischemia/reperfusion and olmesartan-remote ischemic perconditioning. The left ventricular mass index, creatine kinase concentration, infarct size, arrhythmia scores, HIF-1α mRNA expression, miR-21 expression and miR-210 expression were measured. Olmesartan significantly reduced the left ventricular mass index, decreased the creatine kinase concentration, limited the infarct size and reduced the arrhythmia score. The infarct size, creatine kinase concentration and arrhythmia score during reperfusion were similar for the vehicle-ischemia/reperfusion group and vehicle-remote ischemic perconditioning group. However, these values were significantly decreased in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. HIF-1α, miR-21 and miR-210 expression were markedly down-regulated in the Olmesartan-sham group compared to the vehicle-sham group and significantly up-regulated in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. The results indicate that (1) the protective effect of remote ischemic perconditioning is lost in vehicle-treated rats and that chronic treatment with Olmesartan restores the protective effect of remote ischemic perconditioning; (2) chronic treatment with Olmesartan down-regulates HIF-1α, miR-21 and miR-210 expression and reduces hypertrophy, thereby limiting

  15. Olmesartan restores the protective effect of remote ischemic perconditioning against myocardial ischemia/reperfusion injury in spontaneously hypertensive rats

    Directory of Open Access Journals (Sweden)

    Xin Lu

    2015-07-01

    Full Text Available OBJECTIVES: Remote ischemic perconditioning is the newest technique used to lessen ischemia/reperfusion injury. However, its effect in hypertensive animals has not been investigated. This study aimed to examine the effect of remote ischemic perconditioning in spontaneously hypertensive rats and determine whether chronic treatment with Olmesartan could influence the effect of remote ischemic perconditioning. METHODS: Sixty rats were randomly divided into six groups: vehicle-sham, vehicle-ischemia/reperfusion injury, vehicle-remote ischemic perconditioning, olmesartan-sham, olmesartan-ischemia/reperfusion and olmesartan-remote ischemic perconditioning. The left ventricular mass index, creatine kinase concentration, infarct size, arrhythmia scores, HIF-1α mRNA expression, miR-21 expression and miR-210 expression were measured. RESULTS: Olmesartan significantly reduced the left ventricular mass index, decreased the creatine kinase concentration, limited the infarct size and reduced the arrhythmia score. The infarct size, creatine kinase concentration and arrhythmia score during reperfusion were similar for the vehicle-ischemia/reperfusion group and vehicle-remote ischemic perconditioning group. However, these values were significantly decreased in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. HIF-1α, miR-21 and miR-210 expression were markedly down-regulated in the Olmesartan-sham group compared to the vehicle-sham group and significantly up-regulated in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. CONCLUSION: The results indicate that (1 the protective effect of remote ischemic perconditioning is lost in vehicle-treated rats and that chronic treatment with Olmesartan restores the protective effect of remote ischemic perconditioning; (2 chronic treatment with Olmesartan down-regulates HIF-1α, miR-21 and mi

  16. Gypenoside Protects against Myocardial Ischemia-Reperfusion Injury by Inhibiting Cardiomyocytes Apoptosis via Inhibition of CHOP Pathway and Activation of PI3K/Akt Pathway In Vivo and In Vitro

    Directory of Open Access Journals (Sweden)

    Haijie Yu

    2016-06-01

    Full Text Available Background/Aims: Ischemia-reperfusion (I/R injury is believed to be the major cause for detriments in coronary heart diseases, but few effective therapies for prevention or treatment of I/R injury are available. Gypenoside (GP is the predominant effective component of Gynostemma pentaphyllum and possesses capacities against inflammation and oxidation. In the present study, the role of GP in ameliorating myocardial I/R injury was investigated. Methods: effect GP on the cardiac structure of I/R injured rats was assessed by H&E and TTC staining. Then the influence of GP on the cardiac function of rat model was determined by measuring hemodynamics parameters, levels of lactate dehydrogenase (LDH and creatine kinase (CK. Thereafter, effect of GP on apoptotic process was evaluated with both rat and cell models. The production of molecules related to ER stress and apoptosis was quantified for revelation of pathways involved in the myocardial protective effect of GP. Results: Impairments in cardiac structure due to I/R injury was ameliorated by GP treatment. And it was evidently demonstrated that administration of GP not only effectively decreased the apoptotic rates in both rat and cell models but also markedly improved the cardiac function of I/R injured rats. In addition, results of western blotting revealed that the GP inhibited ER-stress and apoptosis through the blockade of CHOP pathway and activation of PI3K/Akt pathway. Conclusion: the current study showed the potential of GP to alleviate myocardial I/R injury and preliminarily uncovered the underling mechanism driving this treatment.

  17. Dissection of Mechanisms of a Chinese Medicinal Formula: Danhong Injection Therapy for Myocardial Ischemia/Reperfusion Injury In Vivo and In Vitro

    Directory of Open Access Journals (Sweden)

    Yue Guan

    2013-01-01

    Full Text Available Traditional Chinese medicine uses a systemic treatment approach, targeting multiple etiological factors simultaneously. Danhong injection (DHI, a very popular Chinese medicine injection, is reported to be effective for many cardiovascular conditions. The primary active ingredients of DHI, and their systemic and interrelated mechanism have not been evaluated in an established myocardial ischemia/reperfusion (MI/R model. We identified the main active constituents in DHI, including hydroxysafflor yellow A (A, salvianolic acid B (B, and danshensu (C, by HPLC fingerprint analysis and assessed their effect on MI/R rats and cardiomyocytes. These 3 compounds and DHI all decreased the levels of IL-1, TNF-α, and MDA, increased those of IL-10 and SOD activity in vivo and in vitro, and had antiapoptotic effects, as shown by flow cytometric analysis and TUNEL assay. Moreover, these compounds increased phosphorylation of Akt and ERK1/2 in cardiomyocytes. Interestingly, we found compound A exerted a more prominent anti-inflammatory effect than B and C, by decreasing NF-κB levels; compound B had more powerful antioxidative capacity than A and C, by increasing Nrf2 expression; compound C had stronger antiapoptotic ability than A and B, by lowering caspase-3 activity. Our results elucidate the mechanisms by which DHI protects against MI/R induced injury.

  18. Distinct effects of acute pretreatment with lipophilic and hydrophilic statins on myocardial stunning, arrhythmias and lethal injury in the rat heart subjected to ischemia/reperfusion.

    Science.gov (United States)

    Čarnická, S; Adameová, A; Nemčeková, M; Matejíková, J; Pancza, D; Ravingerová, T

    2011-01-01

    Although both lipophilic and more hydrophilic statins share the same pathway of the inhibition of HMG-CoA reductase, their pleiotropic cardioprotective effects associated with the ability to cross cellular membranes, including membranes of heart cells, may differ. To test this hypothesis, isolated rat hearts were Langendorff-perfused either with simvastatin (S, 10 micromol/l) or pravastatin (P, 30 micromol/l), 15 min prior to ischemia. Control untreated hearts (C) were perfused with perfusion medium only. Postischemic contractile dysfunction, reperfusion-induced ventricular arrhythmias and infarct size were investigated after exposure of the hearts to 30-min global ischemia and 2-h reperfusion. Both lipophilic S and hydrophilic P reduced the severity of ventricular arrhythmias (arrhythmia score) from 4.3 +/- 0.2 in C to 3.0 +/- 0 and 2.7 +/- 0.2 in S and P, respectively, (both P statins indicating a different ability to cross cardiac membranes may underlie their distinct cardioprotective effects on myocardial stunning and lethal injury induced by ischemia/reperfusion.

  19. Quantum mechanical irreversibility and measurement

    CERN Document Server

    Grigolini, P

    1993-01-01

    This book is intended as a tutorial approach to some of the techniques used to deal with quantum dissipation and irreversibility, with special focus on their applications to the theory of measurements. The main purpose is to provide readers without a deep expertise in quantum statistical mechanics with the basic tools to develop a critical judgement on whether the major achievements in this field have to be considered a satisfactory solution of quantum paradox, or rather this ambitious achievement has to be postponed to when a new physics, more general than quantum and classical physics, will

  20. Crocus sativus L. (saffron) attenuates isoproterenol-induced myocardial injury via preserving cardiac functions and strengthening antioxidant defense system.

    Science.gov (United States)

    Sachdeva, Jaspreet; Tanwar, Vineeta; Golechha, Mahaveer; Siddiqui, Khalid M; Nag, Tapas C; Ray, Ruma; Kumari, Santosh; Arya, Dharamvir S

    2012-09-01

    Saffron (dried stigmas of Crocus sativus L.), a naturally derived plant product, has long been used as a traditional ancient medicine against various human diseases. The aim of the series of experiments was to systematically determine whether saffron exerts cardioprotection in isoproterenol-induced myocardial damage. Male Wistar rats (150-175 g) were divided into five groups: control, isoproterenol (ISO) and three saffron (200, 400 and 800 mg/kg) treatment groups. Aqueous extract of saffron or vehicle was administered orally to rats for four weeks. On days 28 and 29, the animals in ISO and saffron treatment groups were administered ISO (85 mg/kg, s.c.) at an interval of 24 h. On day 30, after recording hemodynamics and left ventricular functions, animals were sacrificed for biochemical, histopathological and electromicroscopical examinations. Isoproterenol challenged animals showed depressed hemodynamics and left ventricular functions as evident by decreased left ventricular rate of peak positive and negative pressure change and elevated left ventricular end-diastolic pressure. Structural and ultrastructural studies further confirmed the damage which was reconfirmed by increased thiobarbituric acid reactive substances (psaffron at all the doses exerted significant cardioprotective effect by preserving hemodynamics and left ventricular functions, maintaining structural integrity and augmenting antioxidant status. Among the different doses used, saffron at 400mg/kg dose exhibited maximum protective effects which could be due to maintenance of the redox status of the cell reinforcing its role as an antioxidant.

  1. Antioxidant effects of ethyl acetate extract of Desmodium gangeticum root on myocardial ischemia reperfusion injury in rat hearts

    Directory of Open Access Journals (Sweden)

    Raman Archana

    2010-01-01

    Full Text Available Abstract Background This study aims to evaluate the antioxidant potential of the ethyl acetate extract of Desmodium gangeticum root for cardioprotection from ischemia reperfusion-induced oxidative stress. Methods The in vitro antioxidant potential of the extract was in terms of hydroxyl radical scavenging activity, lipid peroxide scavenging activity, nitric oxide scavenging activity and diphenylpicrylhydrazyl radical scavenging activity. The in vivo antioxidant potential of the extract was assessed in an isolated rat heart model. Results Free radicals were scavenged by the extract in a concentration-dependent manner within the range of the given concentrations in all models. Administration of the ethyl acetate extract of Desmodium gangeticum root (100 mg per kg body weight before global ischemia caused a significant improvement of cardiac function and a decrease in the release of lactate dehydrogenase in coronary effluent, as well as the level of malondialdehyde in myocardial tissues. Conclusion The ethyl acetate extract of Desmodium gangeticum root protects the myocardium against ischemia-reperfusion-induced damage in rats. The effects of the extract may be related to the inhibition of lipid peroxidation.

  2. Intra-coronary administration of soluble receptor for advanced glycation end-products attenuates cardiac remodeling with decreased myocardial transforming growth factor-β1 expression and fibrosis in minipigs with ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    LU Lin; SHEN Wei-feng; ZHANG Qi; XU Yan; ZHU Zheng-bin; GENG Liang; WANG Ling-jie; JIN Cao; CHEN Qiu-jing; Ann Marie Schmidt

    2010-01-01

    Background The cardioprotective effects of soluble receptor for advanced glycation end-products (sRAGE) have not been evaluated in large animals and the underlying mechanisms are not fully understood. This study aimed to evaluate the effects of intra-coronary administration of sRAGE on left ventricular function and myocardial remodeling in a porcine model of ischemia-reperfusion (I/R) injury. Methods Ten male minipigs with I/R injury were randomly allocated to receive intra-coronary administration of sRAGE (sRAGE group, n=5) or saline (control group, n=5). Echocardiography was performed before and 2 months after infarction. Myocardial expression of transforming growth factor (TGF)-β1was determined by immunohistochemistry and fibrosis was evaluated by Sirius red staining. Results As compared with the baseline values in the control animals, left ventricular end-diastolic volume (from (19.5 5.1) to (32.3 5.6) ml, P <0.05) and end-systolic volume (from (8.3 3.2) to (15.2 4.1) ml, P <0.05) were significantly increased, whereas ejection fraction was decreased (from (61.6 13.3)% to (50.2 11.9)%, P<0.05). No obvious change in these parameters was observed in the sRAGE group. Myocardial expression of TGF-β1 was significantly elevated in the infarct and non-infarct regions in the control group, as compared with sRAGE group (both P<0.01). Fibrotic lesions were consistently more prominent in the infarct region of the myocardium in the control animals (P<0.05). Conclusion Intra-coronary sRAGE administration attenuates RAGE-mediated myocardial fibrosis and I/R injury through a TGF-β1-dependent mechanism, suggesting a clinical potential in treating RAGE/ligand-associated cardiovascular diseases.

  3. Quantum irreversibility in arbitrary dimension

    Energy Technology Data Exchange (ETDEWEB)

    Anselmi, Damiano

    2000-02-14

    Some recent ideas are generalized from four dimensions to the general dimension n. In quantum field theory, two terms of the trace anomaly in external gravity, the Euler density G{sub n} and {open_square}{sup n/2-1}R, are relevant to the problem of quantum irreversibility. By adding the divergence of a gauge-invariant current, G{sub n} can be extended to a new notion of Euler density G-tilde{sub n}, linear in the conformal factor. We call it pondered Euler density. This notion relates the trace-anomaly coefficients a and a{sup '} of G{sub n} and {open_square}{sup n/2-1}R in a universal way (a=a{sup '}) and gives a formula expressing the total RG flow of a as the invariant area of the graph of the beta function between the fixed points. I illustrate these facts in detail for n=6 and check the prediction to the fourth-loop order in the phi (cursive,open) Greek{sup 3}-theory. The formula of quantum irreversibility for general n even can be extended to n odd by dimensional continuation. Although the trace anomaly in external gravity is zero in odd dimensions, I show that the odd-dimensional formula has a predictive content.

  4. Quantum irreversibility in arbitrary dimension

    CERN Document Server

    Anselmi, D

    2000-01-01

    Some recent ideas are generalized from four dimensions to the general dimension n. Two terms of the trace anomaly in external gravity, the Euler density G_n and Box^{n/2-1}R, are relevant to the problem of quantum irreversibility. By adding the divergence of a gauge-invariant current, G_n can be extended to a new notion of Euler density, linear in the conformal factor. We call it pondered Euler density. This notion relates the trace-anomaly coefficients a and a' of G_n and Box^{n/2-1}R in a universal way (a=a') and gives a formula expressing the total RG flow of a as the invariant area of the graph of the beta function between the fixed points. I illustrate these facts in detail for n=6 and check the prediction to the fourth-loop order in the phi^3-theory. The formula of quantum irreversibility for general n even can be extended to n odd by dimensional continuation. Although the trace anomaly in external gravity is zero in odd dimensions, I show that the odd-dimensional formula has a predictive content.

  5. Sildenafil-mediated neovascularization and protection against myocardial ischaemia reperfusion injury in rats: role of VEGF/angiopoietin-1

    Science.gov (United States)

    Koneru, Srikanth; Varma Penumathsa, Suresh; Thirunavukkarasu, Mahesh; Vidavalur, Ramesh; Zhan, Lijun; Singal, Pawan K; Engelman, Richard M; Das, Dipak K; Maulik, Nilanjana

    2008-01-01

    Sildenafil citrate (SC), a drug for erectile dysfunction, is now emerging as a cardiopulmonary drug. Our study aimed to determine a novel role of sildenafil on cardioprotection through stimulating angiogenesis during ischaemia (I) reperfusion (R) at both capillary and arteriolar levels and to examine the role of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) in this mechanistic effect. Rats were divided into: control sham (CS), sildenafil sham (SS), control + IR (CIR) and sildenafil + IR (SIR). Rats were given 0.7 mg/kg, (i.v) of SC or saline 30 min. before occlusion of left anterior descending artery followed by reperfusion (R). Sildenafil treatment increased capillary and arteriolar density followed by increased blood flow (2-fold) compared to control. Treatment with sildenafil demonstrated increased VEGF and Ang-1 mRNA after early reperfusion. PCR data were validated by Western blot analysis. Significant reduction in infarct size, cardiomyocyte and endothelial apoptosis were observed in SC-treated rats. Increased phosphorylation of Akt, eNOS and expression of anti-apoptotic protein Bcl-2, and thioredoxin, hemeoxygenase-1 were observed in SC-treated rats. Echocardiography demonstrated increased fractional shortening and ejection fraction following 45 days of reperfusion in the treatment group. Stress testing with dobutamine infusion and echocardiogram revealed increased contractile reserve in the treatment group. Our study demonstrated for the first time a strong additional therapeutic potential of sildenafil by up-regulating VEGF and Ang-1 system, probably by stimulating a cascade of events leading to neovascularization and conferring myocardial protection in in vivo I/R rat model. PMID:18373738

  6. Irreversible Electroporation of a Hepatocellular Carcinoma Lesion Adjacent to a Transjugular Intrahepatic Portosystemic Shunt Stent Graft

    Energy Technology Data Exchange (ETDEWEB)

    Niessen, Christoph; Jung, Ernst Michael; Wohlgemuth, Walter A. [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany); Trabold, Benedikt [Department of Anaesthesia, University Medical Center Regensburg, Regensburg D-93053 (Germany); Haimerl, Michael; Schreyer, Andreas; Stroszczynski, Christian; Wiggermann, Philipp [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany)

    2013-07-01

    We report in a 65-year-old man hepatocellular carcinoma adjacent to a transjugular intrahepatic portosystemic shunt stent-graft which was successfully treated with irreversible electroporation (IRE). IRE is a new non-thermal tissue ablation technique which uses electrical pulses to induce cell necrosis by irreversible membrane poration. IRE proved to be more advantageous in the ablation of perivascular tumor with little injury to the surrounding structures.

  7. Lyapunov decay in quantum irreversibility.

    Science.gov (United States)

    García-Mata, Ignacio; Roncaglia, Augusto J; Wisniacki, Diego A

    2016-06-13

    The Loschmidt echo--also known as fidelity--is a very useful tool to study irreversibility in quantum mechanics due to perturbations or imperfections. Many different regimes, as a function of time and strength of the perturbation, have been identified. For chaotic systems, there is a range of perturbation strengths where the decay of the Loschmidt echo is perturbation independent, and given by the classical Lyapunov exponent. But observation of the Lyapunov decay depends strongly on the type of initial state upon which an average is carried out. This dependence can be removed by averaging the fidelity over the Haar measure, and the Lyapunov regime is recovered, as has been shown for quantum maps. In this work, we introduce an analogous quantity for systems with infinite dimensional Hilbert space, in particular the quantum stadium billiard, and we show clearly the universality of the Lyapunov regime.

  8. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  9. Acute myocardial involvement after heroin inhalation

    Directory of Open Access Journals (Sweden)

    Ritu Karoli

    2012-01-01

    Full Text Available Amongst the illicit drugs cocaine, amphetamines and cannabis have been studied and documented well to cause myocardial infarction by different mechanisms but there is very sparse data available on myocardial involvement after heroin abuse. We report a young man who developed acute myocardial injury after heroin inhalation and alcohol binge drinking. Heroin induced cardio toxic effect and vasospasm compounded by alcohol were suspected to be the cause of this.

  10. Core-shell hybrid liposomal vesicles loaded with panax notoginsenoside: preparation, characterization and protective effects on global cerebral ischemia/reperfusion injury and acute myocardial ischemia in rats

    Directory of Open Access Journals (Sweden)

    Zhang J

    2012-08-01

    Full Text Available Jing Zhang,1,* Xizhen Han,1,* Xiang Li,2 Yun Luo,1 Haiping Zhao,1 Ming Yang,1 Bin Ni,1 Zhenggen Liao11Key Laboratory of Modern Preparation of TCM, Ministry of Education, 2National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Traditional Chinese Medicine, Nanchang, People's Republic of China*These authors contributed equally to this workPurpose: Novel panax notoginsenoside-loaded core-shell hybrid liposomal vesicles (PNS-HLV were developed to resolve the restricted bioavailability of PNS and to enhance its protective effects in vivo on oral administration.Methods: Physicochemical characterizations of PNS-HLV included assessment of morphology, particle size and zeta potential, encapsulation efficiency (EE%, stability and in vitro release study. In addition, to evaluate its oral treatment potential, we compared the effect of PNS-HLV on global cerebral ischemia/reperfusion and acute myocardial ischemia injury with those of PNS solution, conventional PNS-loaded nanoparticles, and liposomes.Results: In comparison with PNS solution, conventional PNS-loaded nanoparticles and liposomes, PNS-HLV was stable for at least 12 months at 4°C. Satisfactory improvements in the EE% of notoginsenoside R1, ginsenoside Rb1, and ginsenoside Rg1 were shown with the differences in EE% shortened and the greater controlled drug release profiles were exhibited from PNS-HLV. The improvements in the physicochemical properties of HLV contributed to the results that PNS-HLV was able to significantly inhibit the edema of brain and reduce the infarct volume, while it could markedly inhibit H2O2, modified Dixon agar, and serum lactate dehydrogenase, and increase superoxide dismutase (P < 0.05.Conclusion: The results of the present study imply that HLV has promising prospects for improving free drug bioactivity on oral administration.Keywords: liposomes, nanoparticles, panax notoginsenoside, physicochemical properties

  11. Effects of 60 minutes of hyperoxia followed by normoxia before coronary artery bypass grafting on the inflammatory response profile and myocardial injury

    Directory of Open Access Journals (Sweden)

    Karu Inga

    2012-09-01

    Full Text Available Abstract Background Ischemic preconditioning induces tolerance against ischemia-reperfusion injury prior a sustained ischemic insult. In experimental studies, exposure to hyperoxia for a limited time before ischemia induces a low-grade systemic oxidative stress and evokes an (ischemic preconditioning-like effect of the myocardium. We hypothesised that pre-treatment by hyperoxia favours enchanced myocardial protection described by decreased release of cTn T in the 1st postoperative morning and reduces the release of inflammatory cytokines. Methods Forty patients with stable coronary artery disease underwent coronary artery bypass grafting with cardiopulmonary bypass. They were ventilated with 40 or >96% oxygen for 60 minutes followed by by 33 (18–59 min normoxia before cardioplegia. Results In the 1st postoperative morning concentrations of cTnT did not differ between groups ((0.44 (0.26-0.55 ng/mL in control and 0.45 (0.37-0.71 ng/mL in hyperoxia group. Sixty minutes after declamping the aorta, ratios of IL-10/IL-6 (0.73 in controls and 1.47 in hyperoxia, p = 0.03 and IL-10/TNF-α (2.91 and 8.81, resp., p = 0.015 were significantly drifted towards anti-inflammatory, whereas interleukins 6, 8and TNF-α and interferon-γ showed marked postoperative rise, but no intergroup differences were found. Conclusions Pre-treatment by 60 minutes of hyperoxia did not reduce postoperative leak of cTn T in patients undergoing coronary artery bypass surgery. In the hyperoxia group higher release of anti-inflammatory IL-10 caused drifting of IL-10/IL-6 and IL-10/TNF-α towards anti-inflammatory.

  12. 参麦注射液对异丙肾上腺素诱导大鼠心肌缺血的保护作用%Protective effect of Shenmai injection against myocardial ischemia injury induced by isoproterenol in rats

    Institute of Scientific and Technical Information of China (English)

    于佳慧; 刘谈; 郭茂娟; 朱利洁; 陈景瑞; 樊官伟

    2014-01-01

    [目的]研究参麦注射液对异丙肾上腺素诱导大鼠心肌缺血的保护作用。[方法]皮下多点注射异丙肾上腺素(ISO)85 mg/kg,每日1次,连续2 d,制备大鼠心肌缺血模型。记录大鼠心电图(ECG)的变化,观察血流动力学、超声心动图及心肌组织病理学的改变,并测定血清肌酸激酶(CK)、乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)及丙二醛(MDA)的活性以及心脏指数的改变。[结果]参麦注射液能够降低由 ISO 所致的心肌缺血大鼠 ST 段的抬高,明显改善左室功能,降低心肌组织病变程度,并且显著降低 CK、LDH、MDA 水平及心脏指数,增加 SOD 水平,与模型组比较有统计学意义(P<0.05或 P<0.01)。[结论]参麦注射液对 ISO 诱导的大鼠心肌缺血有一定的保护作用。%[Objective] To study the protective effect of Shenmai injection (SMI) against myocardial ischemia injury induced by isoproterenol in rats. [Methods] A rat model of myocardial ischemia was established by subcutaneous injections of isoproterenol (85 mg/kg for two consecutive days). The rat electrocardiogram (ECG) was recorded, the changes of hemodynamics, echocardiography and myocardial histopathology were also observed. Activities of creatine phosphokinase (CK), lactate dehydrogenase (LDH), the superoxide diSMIutase (SOD) and the levels of malondialdehyde (MDA) in rat serum were determined, heart index were measured simultaneously. [Results] In comparison with model group, SMI could inhibit the elevation in ST-segment. The hemodynamic parameters, left ventricular function and myocardial ischemic injury were visibly improved. The levels of CK, LDH and MDA activities and the heart index were significantly decreased. The level of SOD activity was obviously increased (P<0.05 or P<0.01). [Conclusion] SMI has some protective effects against myocardial ischemia injury induced by isoproterenol in rats.

  13. Cardioprotection of Shenfu Injection (参附注射液) against Myocardial Ischemia/Reperfusion Injury in Open Heart Surgery

    Institute of Scientific and Technical Information of China (English)

    ZHENG Chuan-dong; MIN Su

    2008-01-01

    Objective: To investigate the protective effect of Shenfu Injection (参附注射液, SFI) against myocardium ischemia/reperfusion injury (IRI) in rnitral valve replacement (MVR) with cardiopulmonary bypass (CPB). Methods: Forty patients undergoing selective MVR were randomly assigned to the control group and trial Groups ⅠⅡ,Ⅲ, and Ⅳ according to the different administrations of SFI, 8 patients in each group. The changes of systolic blood pressure (SBP), mean blood pressure (MBP), diastolic blood pressure (DBP) in each group were monitored, respectively. The recovering percentage of spontaneous heart beat, the heart rate (HR) and cardiac rhythm as well as the abnormal duration of ECG-ST segment were recorded after the restoration of heart beat. The serum concentration of cardiac troponin Ⅰ (cTnl), malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were determined as well. Results: (1) The SBP, MBP and DBP values, the recovering rate of spontaneous heart beat, HR, ECG-ST, atrioventricular block and ventricular arrhythmia were significantly improved in group Ⅳ compared with any other groups. (2) Compared with the control group, the postoperative serum contents of cTnl and MDA were significantly decreased, but the activity of SOD was significantly increased in group Ⅳ. Conclusions: SFI had a certain protective effect against myocardium IRI. Moreover, better efficacy was seen with the administration of 1.5 mL/kg SFI into CPB priming fluid and pumping 1.5 mL/kg SFI via CPB as soon as the clamped aorta was unclamped.

  14. Mechanisms and therapeutic modulation of myocardial infarct healing

    NARCIS (Netherlands)

    Timmers, L.

    2008-01-01

    This thesis aimed to increase the basic mechanistic understanding of myocardial infarct healing and to develop novel approaches to prevent heart failure following myocardial infarction (MI). Different approaches have been tested to reduce myocardial injury in the acute phase of MI, leading to reduce

  15. Hydrogen gas protects against serum and glucose deprivation‑induced myocardial injury in H9c2 cells through activation of the NF‑E2‑related factor 2/heme oxygenase 1 signaling pathway.

    Science.gov (United States)

    Xie, Qiang; Li, Xue-Xiang; Zhang, Peng; Li, Jin-Cao; Cheng, Ying; Feng, Yan-Ling; Huang, Bing-Sheng; Zhuo, Yu-Feng; Xu, Guo-Hua

    2014-08-01

    Ischemia or hypoxia‑induced myocardial injury is closely associated with oxidative stress. Scavenging free radicals and/or enhancing endogenous antioxidative defense systems may be beneficial for the impediment of myocardial ischemic injury. Hydrogen (H2) gas, as a water‑ and lipid‑soluble small molecule, is not only able to selectively eliminate hydroxyl (·OH) free radicals, but also to enhance endogenous antioxidative defense systems in rat lungs and arabidopsis plants. However, thus far, it has remained elusive whether H2 gas protects cardiomyocytes through enhancement of endogenous antioxidative defense systems. In the present study, the cardioprotective effect of H2 gas against ischemic or hypoxic injury was investigated, along with the underlying molecular mechanisms. H9c2 cardiomyoblasts (H9c2 cells) were treated in vitro with a chemical hypoxia inducer, cobalt chloride (CoCl2), to imitate hypoxia, or by serum and glucose deprivation (SGD) to imitate ischemia. Cell viability and intracellular ·OH free radicals were assessed. The role of an endogenous antioxidative defense system, the NF‑E2‑related factor 2 (Nrf2)/heme oxygenase 1 (HO‑1) signaling pathway, was evaluated. The findings revealed that treatment with CoCl2 or SGD markedly reduced cell viability in H9c2 cells. H2 gas‑rich medium protected against cell injury induced by SGD, but not that induced by CoCl2. When the cells were exposed to SGD, levels of intracellular ·OH free radicals were markedly increased; this was mitigated by H2 gas‑rich medium. Exposure of the cells to SGD also resulted in significant increases in HO‑1 expression and nuclear Nrf2 levels, and the HO‑1 inhibitor ZnPP IX and the Nrf2 inhibitor brusatol aggravated SGD‑induced cellular injury. H2 gas‑rich medium enhanced SGD‑induced upregulation of HO‑1 and Nrf2, and the HO‑1 or Nrf2 inhibition partially suppressed H2 gas‑induced cardioprotection. Furthermore, following genetic silencing of Nrf

  16. Cell therapy in myocardial infarction: emphasis on the role of MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Yuxiang; Bogaert, Jan [University Hospital K.U.L., Department of Radiology, Leuven (Belgium)

    2008-03-15

    Despite tremendous progress in myocardial infarct (MI) treatment, mortality rates remain substantial. Permanent loss of cardiomyocytes after ischemic injury, results in irreversible loss of myocardial contractility, reduction in ventricular performance, and may initiate the development of dilated heart failure. The discovery that pluripotent progenitor cells bear the capacity to differentiate to mature cardiac cells raised the hope of cell-based regenerative medicine. Engraftment of stem cells in the damaged myocardium, repair and functional improvement appeared suddenly a nearby reality. Promising results in animal models, and preliminary studies reporting the feasibility and safety of adult stem cell therapy in MI patients led to the first double-blinded randomized, placebo-controlled trials. The initial great enthusiasm for this paradigm shift in MI treatment has been tempered by the mainly negative or modestly positive study findings. Before new, larger clinical trials can be initiated, a number of critical questions and issues need to be considered starting with a scrutinized analysis of currently available data to extending our knowledge of the mechanism of scarless myocardial regeneration. Cardiac cell therapy necessitates a multidisciplinary approach, whereby imaging, in particular MRI, and the input of the imaging specialist is crucial to the success of cardiac cell regenerative medicine. MRI is an appealing technique for cell trafficking depicting engraftment, differentiation and survival. Endomyocardial cell administration can be achieved safely with MR fluoroscopy and MRI is without any doubt the most accurate and reproducible technique to measure study end-points. (orig.)

  17. Plant Natural Products Calycosin and Gallic Acid Synergistically Attenuate Neutrophil Infiltration and Subsequent Injury in Isoproterenol-Induced Myocardial Infarction: A Possible Role for Leukotriene B4 12-Hydroxydehydrogenase?

    Science.gov (United States)

    Cheng, Yuanyuan; Zhao, Jia; Tse, Hung Fat; Le, X Chris; Rong, Jianhui

    2015-01-01

    Leukotriene B4 12-hydroxydehydrogenase (LTB4DH) catalyzes the oxidation of proinflammatory LTB4 into less bioactive 12-oxo-LTB4. We recently discovered that LTB4DH was induced by two different natural products in combination. We previously isolated gallic acid from Radix Paeoniae through a bioactivity-guided fractionation procedure. The purpose of this study is to test the hypothesis that LTB4DH inducers may suppress neutrophil-mediated inflammation in myocardial infarction. We first isolated the active compound(s) from another plant, Radix Astragali, by the similar strategy. By evaluating LTB4DH induction, we identified calycosin and formononetin from Radix Astragali by HPLC-ESI-MS technique. We confirmed that gallic acid and commercial calycosin or formononetin could synergistically induce LTB4DH expression in HepG2 cells and human neutrophils. Moreover, calycosin and gallic acid attenuated the effects of LTB4 on the survival and chemotaxis of neutrophil cell culture. We further demonstrated that calycosin and gallic acid synergistically suppressed neutrophil infiltration and protected cardiac integrity in the isoproterenol-induced mice model of myocardial infarction. Calycosin and gallic acid dramatically suppressed isoproterenol-induced increase in myeloperoxidase (MPO) activity and malondialdehyde (MDA) level. Collectively, our results suggest that LTB4DH inducers (i.e., calycosin and gallic acid) may be a novel combined therapy for the treatment of neutrophil-mediated myocardial injury.

  18. Plant Natural Products Calycosin and Gallic Acid Synergistically Attenuate Neutrophil Infiltration and Subsequent Injury in Isoproterenol-Induced Myocardial Infarction: A Possible Role for Leukotriene B4 12-Hydroxydehydrogenase?

    Directory of Open Access Journals (Sweden)

    Yuanyuan Cheng

    2015-01-01

    Full Text Available Leukotriene B4 12-hydroxydehydrogenase (LTB4DH catalyzes the oxidation of proinflammatory LTB4 into less bioactive 12-oxo-LTB4. We recently discovered that LTB4DH was induced by two different natural products in combination. We previously isolated gallic acid from Radix Paeoniae through a bioactivity-guided fractionation procedure. The purpose of this study is to test the hypothesis that LTB4DH inducers may suppress neutrophil-mediated inflammation in myocardial infarction. We first isolated the active compound(s from another plant, Radix Astragali, by the similar strategy. By evaluating LTB4DH induction, we identified calycosin and formononetin from Radix Astragali by HPLC-ESI-MS technique. We confirmed that gallic acid and commercial calycosin or formononetin could synergistically induce LTB4DH expression in HepG2 cells and human neutrophils. Moreover, calycosin and gallic acid attenuated the effects of LTB4 on the survival and chemotaxis of neutrophil cell culture. We further demonstrated that calycosin and gallic acid synergistically suppressed neutrophil infiltration and protected cardiac integrity in the isoproterenol-induced mice model of myocardial infarction. Calycosin and gallic acid dramatically suppressed isoproterenol-induced increase in myeloperoxidase (MPO activity and malondialdehyde (MDA level. Collectively, our results suggest that LTB4DH inducers (i.e., calycosin and gallic acid may be a novel combined therapy for the treatment of neutrophil-mediated myocardial injury.

  19. Protective effects of curcumin on myocardial ischemia reperfusion injury in rats%姜黄素对大鼠心肌缺血再灌注损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    伍陈海

    2011-01-01

    Objective To investigate the protective effect of cureumin on oxidative stress injury induced by myocardial ischemia reperfusion in rats. Methods Sixty healthy SD rats were randomized into six groups: sham group, MIR group,PEG group, MIR+ high dose curcumin treatment group, MIR+ middle dose curc umin treatment group, MIR+ low dose curc umin treatment group. Myocardial IR was carried out by ligation of left anterior descending coronary artery for 30 min followed by reperfusion for 60 min. Different dosages of curcumin were administered 30 min before the ligation. Blood was collected at the end of reperfusion for detecting changes of aspartate aminotransferase(AST), lactate dehydrogenase(LDH), lactate dehydrogenasel (LDH1), superoxide dismutase (SOD),and malondialdehyde (MDA). The myocardial infarct size was also estimated. Results Curcumin pretreating dose-dependently decreased the contents of AST, LDH, LDH1 and MDA, and the myocardial infarct size, and increased the activity of SOD. Conclusion Curcumin exerts protective effects on myocardial ischemia reperfusion injury.%目的 探讨姜黄素对大鼠心肌缺血再灌注引起的氧化应激损伤的保护作用.方法 将SD大鼠随机分为6组,每组10只.(1)假手术组;(2)缺血再灌注损伤(MIR)组;(3)溶剂组;(4)姜黄素低、中、高剂量组.建立心肌缺血再灌注模型.用不同剂量姜黄素在结扎前30 min分别做预处理.再灌注结束后采血,测定丙二醛(MDA)、超氧化物歧化酶(SOD)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)、乳酸脱氢酶同工酶(LDH1),并测量心肌梗死面积.结果 姜黄素预处理能明显降低血浆中AST、LDH、LDH1和MDA的含量,提高SOD活性,减少心肌梗死面积.结论 姜黄素对大鼠心肌缺血再灌注引起的氧化应激损伤有保护作用.

  20. Prognostic Impact of Combined Contrast-Induced Acute Kidney Injury and Hypoxic Liver Injury in Patients with ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: Results from INTERSTELLAR Registry.

    Directory of Open Access Journals (Sweden)

    Sang-Don Park

    Full Text Available Besides contrast-induced acute kidney injury(CI-AKI, adscititious vital organ damage such as hypoxic liver injury(HLI may affect the survival in patients with ST-elevation myocardial infarction (STEMI. We sought to evaluate the prognostic impact of CI-AKI and HLI in STEMI patients who underwent primary percutaneous coronary intervention (PCI.A total of 668 consecutive patients (77.2% male, mean age 61.3±13.3 years from the INTERSTELLAR STEMI registry who underwent primary PCI were analyzed. CI-AKI was defined as an increase of ≥0.5 mg/dL in serum creatinine level or 25% relative increase, within 48h after the index procedure. HLI was defined as ≥2-fold increase in serum aspartate transaminase above the upper normal limit on admission. Patients were divided into four groups according to their CI-AKI and HLI states. Major adverse cardiovascular and cerebrovascular events (MACCE defined as a composite of all-cause mortality, non-fatal MI, non-fatal stroke, ischemia-driven target lesion revascularization and target vessel revascularization were recorded.Over a mean follow-up period of 2.2±1.6 years, 94 MACCEs occurred with an event rate of 14.1%. The rates of MACCE and all-cause mortality were 9.7% and 5.2%, respectively, in the no organ damage group; 21.3% and 21.3% in CI-AKI group; 18.5% and 14.6% in HLI group; and 57.7% and 50.0% in combined CI-AKI and HLI group. Survival probability plots of composite MACCE and all-cause mortality revealed that the combined CI-AKI and HLI group was associated with the worst prognosis (p<0.0001 for both.Combined CI-AKI after index procedure and HLI on admission is associated with poor clinical outcomes in patients with STEMI who underwent primary PCI. (INTERSTELLAR ClinicalTrials.gov number, NCT02800421..

  1. Q-Tcd对乳腺癌表阿霉素化疗致心肌损伤的早期预测价值%EARLY PREDICTION VALUE OF Q-T INTERVAL DISPERSION FOR MYOCARDIAL INJURY INDUCED BY EPIRUBICIN IN BREAST CANCER PATIENTS

    Institute of Scientific and Technical Information of China (English)

    张英; 李青山; 刘兰芳; 吕喜英; 白璐

    2015-01-01

    Objective:To investigate the predictive value of Q-T interval dispersion (Q-Tcd) for early myocardial injury induced by epirubicin. Methods:44 breast cancer patients were all treated with epirubicin for 1-5 cycles with the dose was 75mg/m2. The patients were divided into myocardial injury group and non-myocardial injury group according to the troponinⅠlevel;The Q-T interval dispersion and echocardiographic results of patients in 2 groups were compared. Results:44 breast cancer patients, myocardial injury group had 16 patients, non-myocardial injury group had 28 patients. The Q-T interval dispersion of patients in myocardial injury group was obviously higher than that of patients in non-myocardial injury group (P0.05). Conclusions:Compared with left ventricular end diastolic diameter and left ventricular ejection fraction, Q-T interval dispersion is more sensitive for forecasting early myocardial injury induced by epirubicin.%目的::探讨Q-T 间期离散度(Q-Tcd)预测表阿霉素导致早期心肌损伤的应用价值。方法:44例乳腺癌患者均采用含表阿霉素的方案化疗,使用剂量为75mg/m2,治疗1-5个周期。根据肌钙蛋白Ⅰ水平将患者分为心肌损伤组和未发生心肌损伤组,比较患者的Q-T间期离散度和心脏超声结果。结果:44例患者中心肌损伤组16例、未发生心肌损伤组28例。心肌损伤组患者Q-T间期离散度明显高于未发生心肌损伤组(P0.05)。结论:表阿霉素对心肌损伤的评价指标中,Q-T间期离散度较左室舒张末期前后径和射血分数更为敏感,对表阿霉素致心肌病具有预测价值。

  2. Assessment of the autonomic nervous injury by adriamycin using the analysis of heart rate variability

    Energy Technology Data Exchange (ETDEWEB)

    Matsukawa, Seishirou [Toho Univ., Tokyo (Japan). Omori Hospital

    1998-06-01

    Analysis of the heart rate variability were carried out for the cases with malignant tumors of the erythropoietic organ who received adriamycin (ADR), and the effects of ADR on the autonomic nervous of these patients were studied. Seven of 35 cases were examined for the consecutive heart rate variability and {sup 123}I-metaiodobenzylguanidine (MIBG) myocardial SPECT, after the administration of ADR. TP value, LF value, LF/HF and SDANN value were 1,448 msec{sup 2}, 354 msec{sup 2}, 2.0 and 97 msec, respectively, indicating that these values were significantly lower than the healthy controls (the C group) (P<0.01). Consecutive observation for 7 cases of ADR group revealed that TP value decreased from 1,489 msec{sup 2} to 1,058 msec{sup 2}, and HF value decreased from 191 msec{sup 2} to 123 msec{sup 2}, significantly (P<0.05). On the other hand, the washout rate of left ventricle which was estimated from MIBG myocardial SPECT increased from 22{+-}14% to 32{+-}14%, significantly (P<0.05). Though cumulative mean dosage of ADR was 286{+-}148 mg/m{sup 2}, sympathetic nervous injury and parasympathetic nervous was caused by such dose ADR, when examinated by the analysis of the heart rate variability and MIBG myocardial SPECT. It is possible to estimate the myocardial injury of heart autonomic nervous that precedes the injury of heart muscle by ADR, by analyzing the heart rate variability, when the cases with malignant tumors are subject to the chemotherapy. Thus it was suggested that the death by arrhythmia and the irreversible myocardial injury might be predictable. (author)

  3. 芝麻素对大鼠心肌缺血再灌损伤的保护作用%Protective effect of sesamin on myocardial ischemia reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    涂鹏程; 郑书国; 杨解人; 任尤楠; 陶善珺; 赵梦秋; 曹雨朦; 许梦情; 李方圆

    2015-01-01

    目的:探讨芝麻素对缺血再灌所致大鼠心肌损伤的保护作用及其可能机制。方法:SD大鼠50只随机分为正常对照组、模型组、假手术组、芝麻素低剂量组[80 mg/(kg・ d)]及芝麻素高剂量组[160 mg/(kg・ d)],每组10只。芝麻素组灌胃给予芝麻素7 d,每日1次,结扎冠状动脉左前降支建立心肌缺血再灌模型;假手术组大鼠只穿线,不接扎。 HE染色观察心肌病理学变化,比色法测定血清肌酸激酶( CK)、乳酸脱氢酶( LDH)、丙二醛( MDA)、超氧化物歧化酶( SOD)水平及心肌组织MDA、SOD水平。结果:芝麻素明显改善缺血再灌所致大鼠心肌损伤,减轻细胞水肿、变性、坏死及心肌间质炎症细胞浸润,降低血清CK、LDH水平(P<0.05或P<0.01)。芝麻素显著提高大鼠血清和心肌组织SOD活力,降低MDA水平(P<0.05或P<0.01),改善缺血再灌诱导的氧化应激。结论:芝麻素可明显改善缺血再灌所致大鼠心肌损伤,其机制与提高机体抗氧化能力、减轻缺血再灌所致氧化应激损伤有关。%Objective:To investigate the protective effect of sesamin and its potential mechanisms against myocardial ischemia reperfusion injury in rats . Methods:Fifty SD rats were randomly divided into 5 groups:namely control group,model group,sham group,low dose of sesamin group [80 mg/(kg・ d)] and high dose of sesamin group [80 mg/(kg・ d)].Rats in sesamin groups were intragastrically administered with sesamin for 7 d(qd).Then all rats ex-cept those in control and sham groups were subjected to myocardial ischemia for 40 min by coronary artery ligation and subsequent reperfusion for 120 min. Rats in the sham group underwent the same operation without occlusion .Pathological changes of myocardial tissue were examined by hemotoxylin and eosin (HE) staining.Colorimetric assay was performed to determine the serum levels of creatine

  4. Application of Irreversible Thermodynamics to Distillation

    Directory of Open Access Journals (Sweden)

    Signe Kjelstrup

    2004-09-01

    Full Text Available We compare three different ways of modelling tray distillation to each other, and to experimental data: the most common way that assumes equilibrium between the liquid and vapour phases at the outlets of each tray, and two more precise methods that use irreversible thermodynamics. Irreversible thermodynamics determines the driving forces and fluxes of a system in agreement with the second law. It is shown that the methods using irreversible thermodynamics (Maxwell-Stefan equations are superior to the method that assumes that equilibrium is reached on each tray. The Soret effect must be included to have a good description of the heat flux.

  5. Silent myocardial ischemia.

    Science.gov (United States)

    Gutterman, David D

    2009-05-01

    Although much progress has been made in reducing mortality from ischemic cardiovascular disease, this condition remains the leading cause of death throughout the world. This might in part be due to the fact that over half of patients have a catastrophic event (heart attack or sudden death) as their initial manifestation of coronary disease. Contributing to this statistic is the observation that the majority of myocardial ischemic episodes are silent, indicating an inability or failure to sense ischemic damage or stress on the heart. This review examines the clinical characteristics of silent myocardial ischemia, and explores mechanisms involved in the generation of angina pectoris. Possible mechanisms for the more common manifestation of injurious reductions in coronary flow; namely, silent ischemia, are also explored. A new theory for the mechanism of silent ischemia is proposed. Finally, the prognostic importance of silent ischemia and potential future directions for research are discussed.

  6. α-Lipoic acid reduces infarct size and preserves cardiac function in rat myocardial ischemia/reperfusion injury through activation of PI3K/Akt/Nrf2 pathway.

    Directory of Open Access Journals (Sweden)

    Chao Deng

    Full Text Available BACKGROUND: The present study investigates the effects and mechanisms of α-Lipoic acid (LA on myocardial infarct size, cardiac function and cardiomyocyte apoptosis in rat hearts subjected to in vivo myocardial ischemia/reperfusion (MI/R injury. METHODOLOGY/PRINCIPAL FINDINGS: Male adult rats underwent 30 minutes of ischemia followed by 3, 24, or 72 h of reperfusion. Animals were pretreated with LA or vehicle before coronary artery ligation. The level of MI/R- induced LDH and CK release, infarct size, cardiomyocyte apoptosis and cardiac functional impairment were examined and compared. Western blot analysis was performed to elucidate the mechanism of LA pretreatment. The level of inflammatory cytokine TNF-α released to serum and accumulated in injured myocardium as well as neutrophil accumulation in injured myocardium were also examined after MI/R injury. Our results reveal that LA administration significantly reduced LDH and CK release, attenuated myocardial infarct size, decreased cardiomyocytes apoptosis, and partially preserved heart function. Western blot analysis showed that LA pretreatment up-regulated Akt phosphorylation and Nrf2 nuclear translocation while producing no impact on p38MAPK activation or nitric oxide (NO production. LA pretreatment also increased expression of HO-1, a major target of Nrf2. LA treatment inhibited neutrophil accumulation and release of TNF-α. Moreover, PI3K inhibition abolished the beneficial effects of LA. CONCLUSIONS/SIGNIFICANCE: This study indicates that LA attenuates cardiac dysfunction by reducing cardiomyoctyes necrosis, apoptosis and inflammation after MI/R. LA exerts its action by activating the PI3K/Akt pathway as well as subsequent Nrf2 nuclear translocation and induction of cytoprotective genes such as HO-1.

  7. Novel adjunctive treatments of myocardial infarction

    DEFF Research Database (Denmark)

    Schmidt, Michael Rahbek; Pryds, Kasper; Bøtker, Hans Erik

    2014-01-01

    Myocardial infarction is a major cause of death and disability worldwide and myocardial infarct size is a major determinant of prognosis. Early and successful restoration of myocardial reperfusion following an ischemic event is the most effective strategy to reduce final infarct size and improve...... by endovascular infusion of cold saline all reduce infarct size and may confer clinical benefit for patients admitted with acute myocardial infarcts. Equally promising, three follow-up studies of the effect of remote ischemic conditioning (RIC) show clinical prognostic benefit in patients undergoing coronary...... clinical outcome, but reperfusion may induce further myocardial damage itself. Development of adjunctive therapies to limit myocardial reperfusion injury beyond opening of the coronary artery gains increasing attention. A vast number of experimental studies have shown cardioprotective effects of ischemic...

  8. Expression of microRNA-126 in myocardial tissue of rats in the early stage of severe burn injury and its relation with myocardial damage%严重烧伤早期大鼠心肌组织微小RNA-126的表达变化及其与心肌损害的关系

    Institute of Scientific and Technical Information of China (English)

    谢琼慧; 叶子青; 陈斓; 赵超莉; 阮琼芳; 谢卫国

    2015-01-01

    水平呈明显负相关(r=-0.797,P<0.001).(2)与正常对照组比较,刺激组、转染+刺激组心肌细胞微小RNA-126表达分别明显下降、升高(t值分别为4.57、5.73,P<0.05或P<0.01),心肌细胞活力均明显下降(t值分别为14.88、6.48,P值均小于0.01),心肌细胞凋亡率均显著升高(t值分别为13.82、6.96,P值均小于0.01);与阴性转染+刺激组比较,转染+刺激组心肌细胞微小RNA-126表达明显升高(t=6.77,P<0.01),心肌细胞活力明显升高(t=8.23,P<0.001),心肌细胞凋亡率明显降低(t=6.14,P<0.001).结论 大鼠严重烧伤早期心肌组织微小RNA-126表达下降,其可能参与烧伤早期心肌损害的调控并发挥保护作用.%Objective To observe the changes in the expressions of microRNA-126 in myocardial tissue and cardiac troponin Ⅰ (cTnⅠ) in serum of rats in the early stage of severe burn injury with analysis of their relationship, and to validate the relationship between microRNA-126 and myocardial damage in cellular level.Methods (1) Forty-eight SD rats were divided into sham injury group (n =8, without fluid therapy after sham injury) and burn injury group (n =40, inflicted with 30% TBSA full-thickness scald on the back, hereinafter referred to as burn, and received intraperitoneally injection of lactic acid Ringer's solution) according to the random number table.Blood was collected from abdominal aorta of rats in sham injury group at post injury hour (PIH) 1, and then these 8 rats were sacrificed for obtaining left ventricular tissue.Blood was respectively collected from abdominal aorta of 8 rats in burn injury group at PIH 3, 6, 12, 24, and 48, and then they were sacrificed and the left ventricular tissue was obtained at each time point.The expression of microRNA-126 in myocardial tissue was assessed by real-time fluorescent quantitative RT-PCR.Serum level of cTnⅠ was assessed by ELISA.(2) Rat myocardial cell line H9C2 was divided into normal control group (NC, routinely cultured) , stimulation

  9. Does an irreversible chemical cycle support equilibrium?

    CERN Document Server

    Banerjee, Kinshuk

    2013-01-01

    The impossibility of attaining equilibrium for cyclic chemical reaction networks with irreversible steps is apparently due to a divergent entropy production rate. A deeper reason seems to be the violation of the detailed balance condition. In this work, we discuss how the standard theoretical framework can be adapted to include irreversible cycles, avoiding the divergence. With properly redefined force terms, such systems are also seen to reach and sustain equilibria that are characterized by the vanishing of the entropy production rate, though detailed balance is not maintained. Equivalence of the present formulation with Onsager's original prescription is established for both reversible and irreversible cycles, with a few adjustments in the latter case. Further justification of the attainment of true equilibrium is provided with the help of the minimum entropy production principle. All the results are generalized for an irreversible cycle comprising of N number of species.

  10. Irreversible thermodynamics of Poisson processes with reaction.

    Science.gov (United States)

    Méndez, V; Fort, J

    1999-11-01

    A kinetic model is derived to study the successive movements of particles, described by a Poisson process, as well as their generation. The irreversible thermodynamics of this system is also studied from the kinetic model. This makes it possible to evaluate the differences between thermodynamical quantities computed exactly and up to second-order. Such differences determine the range of validity of the second-order approximation to extended irreversible thermodynamics.

  11. Irreversible thermodynamics of Poisson processes with reaction

    Science.gov (United States)

    Méndez, Vicenç; Fort, Joaquim

    1999-11-01

    A kinetic model is derived to study the successive movements of particles, described by a Poisson process, as well as their generation. The irreversible thermodynamics of this system is also studied from the kinetic model. This makes it possible to evaluate the differences between thermodynamical quantities computed exactly and up to second-order. Such differences determine the range of validity of the second-order approximation to extended irreversible thermodynamics.

  12. Protective effect of moringa seed on myocardial ischemia reperfusion injury in rats%辣木籽对大鼠心肌缺血再灌注损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    曲震理

    2016-01-01

    Objective To explore the protective effect of moringa on myocardial ischemia reperfusion injury in rats.Methods 75 SD rats were selected and divided into a sham operation group,a model group,a high dose group,a middle dose group,and a low dose group.The sham operation group and the model group were given the same volume of physiological saline by gavage and the high dose group,the medium middle dose group,and the low dose group moringa seed suspension liquid 0.5 g/kg,1.0 mg/kg,and 2.0 g/kg by gavage,respectively.Myocardial ischemia reperfusion injury model was made;the ischemia time was 30 minutes;and the reperfusion time was 120 minutes.Myocardial infarction area was measured.The levels of serum lactate dehydrogenase,isoenzyme of creatine kinase,malondialdehyde,and superoxide dismutase were detected.Results The myocardial infarction area was larger in the model group than in the sham operation group (P<0.05).The area of myocardial infarction was lower in the high dose group,the middle dose group,and the low dose group than in the model group (P<0.05).The activities of lactic acid dehydrogenase,creatine kinase,and superoxide dismutase enzyme and the malondialdehyde content in the high dose group,the middle dose group,and the low dose group were statistically different from those in the model group (P<0.05).Conclusion Moringa seed has protective effect on myocardial ischemia reperfusion injury in rats,which may relate to its antioxidant effect.%目的 探讨辣木籽对大鼠心肌缺血再灌注损伤的保护作用.方法 选择SD大鼠75只,分为假手术组、模型组、高剂量组、中剂量组、低剂量组,假手术组和模型组分别给予同体积生理盐水灌胃,高中低剂量组分别给予辣木籽混悬液0.5 g/kg、1.0 mg/kg、2.0 g/kg灌胃.制作心肌缺血再灌注损伤模型,缺血30分钟,再灌注120分钟.观察心肌梗死范围,测定血清乳酸脱氢酶、磷酸肌酸激酶、丙二醛、超氧化物歧化酶水平.结果

  13. A New Therapeutic Modality for Acute Myocardial Infarction: Nanoparticle-Mediated Delivery of Pitavastatin Induces Cardioprotection from Ischemia-Reperfusion Injury via Activation of PI3K/Akt Pathway and Anti-Inflammation in a Rat Model.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Nagaoka

    Full Text Available There is an unmet need to develop an innovative cardioprotective modality for acute myocardial infarction (AMI, for which the effectiveness of interventional reperfusion therapy is hampered by myocardial ischemia-reperfusion (IR injury. Pretreatment with statins before ischemia is shown to reduce MI size in animals. However, no benefit was found in animals and patients with AMI when administered at the time of reperfusion, suggesting insufficient drug targeting into the IR myocardium. Here we tested the hypothesis that nanoparticle-mediated targeting of pitavastatin protects the heart from IR injury.In a rat IR model, poly(lactic acid/glycolic acid (PLGA nanoparticle incorporating FITC accumulated in the IR myocardium through enhanced vascular permeability, and in CD11b-positive leukocytes in the IR myocardium and peripheral blood after intravenous treatment. Intravenous treatment with PLGA nanoparticle containing pitavastatin (Pitavastatin-NP, 1 mg/kg at reperfusion reduced MI size after 24 hours and ameliorated left ventricular dysfunction 4-week after reperfusion; by contrast, pitavastatin alone (as high as 10 mg/kg showed no therapeutic effects. The therapeutic effects of Pitavastatin-NP were blunted by a PI3K inhibitor wortmannin, but not by a mitochondrial permeability transition pore inhibitor cyclosporine A. Pitavastatin-NP induced phosphorylation of Akt and GSK3β, and inhibited inflammation and cardiomyocyte apoptosis in the IR myocardium.Nanoparticle-mediated targeting of pitavastatin induced cardioprotection from IR injury by activation of PI3K/Akt pathway and inhibition of inflammation and cardiomyocyte death in this model. This strategy can be developed as an innovative cardioprotective modality that may advance currently unsatisfactory reperfusion therapy for AMI.

  14. Acetaldehyde dehydrogenase 2 activation inhibits myocardial ischemia-reperfusion injury in senescent rats%激活乙醛脱氢酶2抑制老年大鼠心肌缺血再灌注损伤

    Institute of Scientific and Technical Information of China (English)

    邢媛; 殷玥; 石曌玲; 李晨; 王博文; 王衍帅; 高峰; 马恒

    2013-01-01

    Objective Aging heart shows significantly reduced tolerance to myocardial ischemia/reperfusion (I/R) injury, so senescent heart is prone to be damaged by the injury. This study was designed to investigate the protective effect of acetaldehyde dehydrogenase 2 (ALDH2) agonist Alda-1 in aging rats after myocardial I/R injury. Methods A total of 40 aging male Sprague Dawley (SD) rats (at an age of 20 to 22 months) were randomized into I/R group (I/R) and Alda-1 group (I/R + Alda). Another 40 adult rats at an age of 3 to 4 months served as adult control. Rat acute myocardial I/R model was established by ligation of left anterior descending artery for 30min followed by reperfusion for 4h. Alda-l(16mg/kg) and normal saline at the same volume were intravenously infused at a flow rate of 2ml/(kg · h) into the left ventricle of corresponding rats in 5min before reperfusion. The left ventricular pressure was monitored at the same time. At the end of 4 hours reperfusion, ALDH2 activity, reactive oxygen species (ROS) production, and protein carbonylation in the myocardial tissue were measured. Serum level of lactate dehydrogenase (LDH) was tested. Results A significant decrease in ALDH2 activity was observed in the aging hearts, but this effect was blocked by Alda-1. Compared with the adult hearts, myocardial I/R injury was significantly aggravated in aging hearts, which were evidenced by reduced ± LVdP/dtmax and increased serum level of LDH (P < 0.05). ALDH2 activator infusion during reperfusion effectively suppressed the above mentioned ischemic injury in the aging hearts (P < 0.05). Furthermore, protein carbonylation and ROS production in the myocardium were increased in the aging hearts compared with the adult hearts (P < 0.05), which was attenuated by Alda-1 treatment. Conclusion Activating myocardial ALDH2 significantly improves the resistance ability to myocardial I/R injury in aging heart. ALDH2-induced cardiac protection may be through suppressing myocardial I

  15. Analysis of the results of 838 cases of myocardial injury markers in neonates%新生儿心肌损伤标志物检测838例结果分析

    Institute of Scientific and Technical Information of China (English)

    罗德幸; 石坤; 方钰; 悦光; 杜逸亭; 刘成桂; 曹登成

    2015-01-01

    Objective To investigate the diagnostic value and significance of myocardial injury markers in neonates.Methods A retrospective analysis of 838 cases of myocardial injury markers in neonates,the total positive rate of hs -cTnI and the positive rates of hs -cTnI(hypersensitivity cardiac troponin I)in different kinds of neonatal disease were calculated,the levels of abnormalities consistent rate in hs -cTnI and CK -MBmass(creatine kinase MB mass)were compared with hs -cTnI and MYO(Myoglobin).Results The total positive rate of hs -cTnI was 40.33% in the 838 neonates.The highest incidence of myocardial injury was neonatal sepsis (57.14%),followed by neonatal pulmonary hemorrhage (55.56%)and neonatal convulsions (54.55%).The abnormalities consistent rate of hs -cTnI and CK -MBmass was better than hs -cTnI and MYO (85.50% vs 28.11%,χ2 =226.9,P <0.05). Conclusion Neonatal hospitalized children often complicated by myocardial injury;As a biochemical myocardial injury marker,the hs -cTnI detection is important for early detection of myocardial injury,it should be recommend as routine test items;CK -MBmass has better correlation with hs -cTnI than MYO,which can provide guide for doctors to interpret the data of myocardial injury markers.%目的:对新生儿心肌损伤标志物结果进行分析研究,以探讨其在新生儿疾病中的诊断价值及意义。方法回顾性分析838例新生儿住院患儿心肌损伤标志物的检验结果,统计超敏肌钙蛋白 I(hs-cTnI)总阳性率及不同新生儿病种间 hs-cTnI 阳性率,计算 hs-cTnI 与肌酸激酶心型同工酶质量(CK-MBmass)及肌红蛋白(MYO)的异常符合率。结果838例患儿中,hs-cTnI 总阳性率为40.33%;在新生儿疾病中,新生儿败血症心肌损伤发生率最高(57.14%),其次为新生儿肺出血(55.56%)以及新生儿惊厥(54.55%);hs-cTnI 与CK-MBmass 异常符合率优于 hs-cTnI 与 MYO 异常符合率(85.50%比28

  16. Effects of propofol pretrement on myocardial ischemia-reperfusion injury in diabetic rats%异丙酚预先给药对糖尿病大鼠心肌缺血再灌注损伤的影响

    Institute of Scientific and Technical Information of China (English)

    王红杰; 张建新; 李兰芳; 武宏敏

    2008-01-01

    目的 探讨异丙酚预先给药对糖尿病大鼠心肌缺血再灌注损伤的影响.方法 健康雄性SD大鼠84只,体重230~280 g,随机分为7组(n=12),假手术组(Ⅰ组);Ⅱ组采用结扎左冠状动脉前降支30 min,再灌注120 min制备心肌缺血再灌注模型;糖尿病大鼠假手术组(Ⅲ组)采用腹腔注射链脲左菌素(STZ)55 mg/kg制备糖尿病模型;糖尿病大鼠心肌缺血再灌注组(Ⅳ组)腹腔注射STZ 3周后制备心肌缺血再灌注模型;Ⅴ组、Ⅵ组和Ⅶ组糖尿病大鼠分别于缺血前10 min至再灌注120 min时静脉输注异丙酚3、6、12 mg·kg-1·h-1.记录再灌注120 min时心率(HR)、左心室收缩峰压、左心室舒张末压(LVDEP)及左心室内压上升,下降最大速率(±dp/dtmax),计算左心室发展压(LVDP);测定血清肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)活性、心肌组织超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、心肌线粒体肿胀度、总ATP酶和谷胱苷肽过氧化物酶(GSH-Px)活性;透射电镜观察心肌组织超微结构.结果 与Ⅲ组比较,Ⅳ组HR、LVDP和±dp/dtmax、心肌组织SOD活性、线粒体总ATP酶及GSH-Px活性降低,LVEDP、血清LDH、CK-MB活性、心肌组织MDA含量及线粒体肿胀度升高(P<0.05或0.01);与Ⅳ组比较,Ⅵ组和Ⅶ组HR、LVDP和±dp/dtmax、心肌组织SOD活性、线粒体总ATP酶及GSH-Px活性升高,LVEDP、血清LDH、CK-MB活性、心肌组织MDA含量和线粒体肿胀度降低,Ⅴ组+dp/dtmax及线粒体总ATP酶活性升高,血清CK-MB活性降低(P<0.05).Ⅵ组和Ⅷ组心肌组织超微结构损伤减轻.结论 异丙酚6、12 mg·kg-1·h-1预先给药可减轻糖尿病大鼠心肌缺血再灌注损伤,可能与其抑制心肌组织脂质过氧化反应,改善心肌细胞线粒体膜通透性有关.%Objective To investigate the effects of propofol pretreatment on myocardial ischemia-reperfusion (I/R) injury in diabetic rats. Methods Eighty-four male SD rats weighing 230-280 g were

  17. Inhibition of Fas-associated death domain-containing protein (FADD protects against myocardial ischemia/reperfusion injury in a heart failure mouse model.

    Directory of Open Access Journals (Sweden)

    Qian Fan

    Full Text Available AIM: As technological interventions treating acute myocardial infarction (MI improve, post-ischemic heart failure increasingly threatens patient health. The aim of the current study was to test whether FADD could be a potential target of gene therapy in the treatment of heart failure. METHODS: Cardiomyocyte-specific FADD knockout mice along with non-transgenic littermates (NLC were subjected to 30 minutes myocardial ischemia followed by 7 days of reperfusion or 6 weeks of permanent myocardial ischemia via the ligation of left main descending coronary artery. Cardiac function were evaluated by echocardiography and left ventricular (LV catheterization and cardiomyocyte death was measured by Evans blue-TTC staining, TUNEL staining, and caspase-3, -8, and -9 activities. In vitro, H9C2 cells transfected with ether scramble siRNA or FADD siRNA were stressed with chelerythrin for 30 min and cleaved caspase-3 was assessed. RESULTS: FADD expression was significantly decreased in FADD knockout mice compared to NLC. Ischemia/reperfusion (I/R upregulated FADD expression in NLC mice, but not in FADD knockout mice at the early time. FADD deletion significantly attenuated I/R-induced cardiac dysfunction, decreased myocardial necrosis, and inhibited cardiomyocyte apoptosis. Furthermore, in 6 weeks long term permanent ischemia model, FADD deletion significantly reduced the infarct size (from 41.20 ± 3.90% in NLC to 26.83 ± 4.17% in FADD deletion, attenuated myocardial remodeling, improved cardiac function and improved survival. In vitro, FADD knockdown significantly reduced chelerythrin-induced the level of cleaved caspase-3. CONCLUSION: Taken together, our results suggest FADD plays a critical role in post-ischemic heart failure. Inhibition of FADD retards heart failure progression. Our data supports the further investigation of FADD as a potential target for genetic manipulation in the treatment of heart failure.

  18. The role of inflammatory response in myocardial ischemia reperfusion injury%炎症反应在心肌缺血/再灌注损伤中作用的研究进展

    Institute of Scientific and Technical Information of China (English)

    熊军; 薛富善; 廖旭

    2011-01-01

    Background Myocardial/ischemia reperfusion injury (I/RI) is defined as myocardial injury caused by the restoration of coronary blood flow after an ischemic episode, which leads to severe myocyte metabolic derangements and ultrastructural impairment. The I/RI also triggers the activation of an inflammatory cascade evidenced by neutrophils accumulating and inflammatory mediators releasing. Thus the inflammatory response has been recognized as one of the most important mechanisms of I/ RI. It has been identified that reperfusion -induced inflammation and excessive production of cytokines can promote myocardial damage during ischemia and reperfusion. Thus modulating the inflammatory response at the onset of reperfusion may represent a potent therapeutic strategy to attenuate the myocardial I/RI. Objective Objects of this review are to evaluate the possible roles of the inflammatory response in mechanisms of myocardial I/RI. Content The effects of inflammatory mediators including inflammatory cells and cytokines in I/RI process are in detailed introduced. Trend The inflammatory response is exactly an important mechanism in IRI, but its effects in the I/RI process are not simple. Except damages caused by the inflammatory response, it can produce benefits. For improving cardioprotection, all treatments by regulating I/RI -induced inflammation should keep the balance of its two sides.%背景 心肌缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)是指在缺血心肌恢复血流灌注后,细胞代谢功能障碍和结构破坏反而加重的现象,并且伴随有以炎症细胞浸润和细胞因子产生为特征的炎症反应.目前认为,炎症反应是I/RI的重要病理机制之一,再灌注诱发的炎症反应及其介质可加重心肌I/RI,而调控炎症反应则可减轻心肌I/RI.目的 评价炎症反应在心肌I/RI发生机制中的作用.内容 详细描述了具体炎症细胞和炎性细胞因子在I/RI过程中的作用.趋向 炎症反应参与

  19. Protective Effects of Total Polyphenols Extracted from Toona sinensis on Myocardial Ischemia/reperfusion-induced Injury in Rats%香椿子总多酚对心肌缺血再灌注大鼠的保护作用

    Institute of Scientific and Technical Information of China (English)

    李红月; 陈超

    2011-01-01

    Objective: To investigate the protective effects of total polyphenols extracted from Toona sinensis on myocardial ischemia/reperfusion-induced injury in rats. Method: Fifty SD rats were randomly divided into 5 groups: a sham operation group (Sham), a model group treated by ligation of the left coronary artery plus administration of 0.5% sodium carboxymethyl cellulose (Model), a group with model animals treated by intragastrical administration of a low dose of total polyphenols extracted from T. sinensis (50 mg· kg-1, XD), a group treated by a moderate dose (100 mg·kg-1, XZ), and a group treated by high dose (200 kg-1 ·XG).Myocardial ischemia/reperfusion-induced injury was made by legating the left coronary artery (LCA) for 30 min followed by a 120 min reperfusion in anesthetized rats. After reperfusion, the levels of phosphocreatine kinase ( CK), troponin I ( cTnI), superoxide dismutase (SOD) and malondialdehyde ( MDA ) in serum were detected.Finally, the hearts of rats were cut into 5 pieces and stained by 1% TTC for 15 min; the degree of myocardial infarction was calculated. Result: Compared with the rats in model group, after administrated with polyphenols extracted from T. sinensis, the levels of CK, cTnT-I and MDA in serum were decreased, the activity of SOD was increased, and the severity of myocardial infarction was alleviated. Conclusion: Total polyphenols extracted from T. sinensis played a protective role in myocardial ischemia/reperfusion-induced injury.%目的:观察香椿子总多酚对心肌缺血再灌注大鼠的保护作用.方法:50只SD大鼠随机分成假手术组:冠脉下穿线不结扎+0.5%羧甲基纤维素钠、模型组:冠脉下穿线结扎+0.5%羧甲基纤维素钠、香椿子总多酚低剂量(XD,50 mg·kg-1)+冠脉下穿线结扎、中剂量(XZ,100 mg·kg-1)+冠脉下穿线结扎、高剂量(XG,200 mg·kg-1)+冠脉下穿线结扎组,各组均ig给药.采用左冠状动脉前降支结扎30 min再灌120 min的方法复制大鼠

  20. Myocardial disease

    Institute of Scientific and Technical Information of China (English)

    1992-01-01

    920666 Immunocytochemical study ofCuZn superoxide dismutase in the myocardi-um of normal subjects and patients ofrheumatic heart disease.ZHENG Yi(郑毅),et al. Dept Intern Med, Navy General Hosp,PLA, Beijing. 100037. Natl Med J China 1992;72(4): 225-227. By using the methods of immunocytochemistry

  1. Diagnosing Myocardial Contusion after Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Zahra Alborzi

    2016-10-01

    Full Text Available A myocardial contusion refers to a bruise of the cardiac muscle, the severity of which can vary depending on the severity of the injury and when the injury occurs. It is a major cause of rapid death which happens after blunt chest trauma and should be suspected at triage in the emergency department. We demonstrated that suspected myocardial contusion patients who have normal electrocardiograms (ECGs and biomarker tests can be safely discharged. However, if the test results are abnormal, the next steps should be echocardiography and more advanced measures. Diagnosing myocardial contusion is very difficult because of its nonspecific symptoms. If a myocardial contusion happens, cardiogenic shock or arrhythmia must be anticipated, and the patient must be carefully monitored.

  2. Efficiency of Rectification: Reversible vs. Irreversible Regimes

    Science.gov (United States)

    Sokolov, I. M.

    2002-11-01

    Both man-made locomotive devices and molecular motors use gears to transform a reciprocating motion into a directed one. One of the most common gears is a rectifier, a mechanically irreversible appliance. The maximal energetic efficiency of an isothermic gear is bounded by unity, as a consequence of the Second Law. However, approaching this ideal efficiency does not imply approaching reversibility. We discuss what properties of a rectifier mostly influence the transduction efficiency and show that an appliance which locks under backward force is just the one which can approach the ideal efficiency either in the reversible or in the irreversible regime.

  3. Glycogen Phosphorylase Isoenzyme BB:A New Biomarker of Myocardial Injury%糖原磷酸化酶同工酶脑型:心肌损伤的新标志物

    Institute of Scientific and Technical Information of China (English)

    王宇竞

    2011-01-01

    Glycogen phosphorylase isoenzyme BB ( GPBB) is a key enzyme of glycogenolysis, as an enzyme for early laboratory detection of ischaemia.At present, GPBB is the most promising because it increases as early as one to four hours from the onset of chest pain.Its early release appears to be essentially dependent on ischemic myoeardial injury.Compared with the established cardiac markers, GPBB is a sensitive marker for the early diagnosis of acute coronary syndromes.Both multiple biomarkers and enzyme linked immunosorbent assay are used for the determination GPBB.GPBB is not only a marker of monitoring acute coronary syndromes,but also may be a marker of myocardial necrosis and ischemia caused by other myocardial injury factors.%糖原磷酸化酶同工酶脑型(GPBB)是糖原分解的关键酶,最早在实验室因缺血而被检测到.目前,GPBB成为最具潜质的心肌损伤生物标记,其在胸痛开始的1~4 h内浓度开始增加,并且释放本质上依赖于心肌缺血损伤.对比其他已知心肌标志物,GPBB对于诊断冠状动脉综合征中不同形式的心肌缺血损伤具有高度敏感性和特异性.近期随着酶联免疫吸附法、多种生物标记技术测定GPBB含量的应用,GPBB还可能应用于其他原因所致的心肌损害.

  4. Preliminary evaluation of treatment efficacy of umbilical cord blood-derived mesenchymal stem cell-differentiated cardiac pro-genitor cells in a myocardial injury mouse model

    Directory of Open Access Journals (Sweden)

    Truc Le-Buu Pham

    2015-12-01

    Full Text Available Recently, stem cell therapy has been investigated as a strategy to prevent or reverse damage to heart tissue. Although the results of cell transplantation in animal models and patients with myocardial ischemia are promising, the selection of the appropriate cell type remains an issue that requires consideration. In this study, we aimed to evaluate the effect of cardiac progenitor cell transplantation in a mouse model of myocardial ischemia. The cardiac progenitor cells used for transplantation were differentiated from umbilical cord blood mesenchymal stem cells. Animal models injected with phosphate-buffered saline (PBS and healthy mice were used as controls. Cell grafting was assessed by changes in blood pressure and histological evaluation. After 14 days of transplantation, the results demonstrated that the blood pressure of transplanted mice was stable, similar to healthy mice, whereas it fluctuated in PBS-injected mice. Histological analysis showed that heart tissue had regenerated in transplanted mice, but remained damaged in PBS-injected mice. Furthermore, trichrome staining revealed that the transplanted mice did not generate significant amount of scar tissue compared with PBS-injected control mice. In addition, the cardiac progenitor cells managed to survive and integrate with local cells in cell-injected heart tissue 14 days after transplantation. Most importantly, the transplanted cells did not exhibit tumorigenesis. In conclusion, cardiac progenitor cell transplantation produced a positive effect in a mouse model of myocardial ischemia. [Biomed Res Ther 2015; 2(12.000: 435-445

  5. Risk Aversion, Price Uncertainty and Irreversible Investments

    NARCIS (Netherlands)

    van den Goorbergh, R.W.J.; Huisman, K.J.M.; Kort, P.M.

    2003-01-01

    This paper generalizes the theory of irreversible investment under uncertainty by allowing for risk averse investors in the absence of com-plete markets.Until now this theory has only been developed in the cases of risk neutrality, or risk aversion in combination with complete markets.Within a gener

  6. Effects of Jiawei Danshen Decoction on Myocardial Ischemia Reperfusion Injury in Rabbits with Blood Stasis Syndrome%加味丹参饮对血瘀证兔心肌缺血再灌注损伤的影响

    Institute of Scientific and Technical Information of China (English)

    李鑫辉; 黄政德; 葛金文

    2011-01-01

    目的 探讨加味丹参饮对血瘀证兔心肌缺血再灌注损伤(IRI)的影响及其机制.方法 家兔60只,随机分为空白组、血瘀证组、IRI组、预处理组、丹参组、加味丹参饮组,每组10只.建立血瘀证兔IRI模型,采用加味丹参饮对该模型进行干预,采用全自动生化分析仪检测乳酸脱氢酶(LDH)和肌酸激酶同功酶(CK-MB)的水平变化,末端探针标记法观察心肌细胞凋亡,透射电镜观察心肌细胞超微结构.结果 IRI组LDH和CK-MB水平明显升高,心肌细胞凋亡显著增加,与空白组比较差异具有统计学意义(P<0.01);加味丹参饮组可以降低LDH和CK-MB水平,抑制心肌细胞凋亡,与IRI组比较差异具有统计学意义(P<0.05或P<0.01).电镜观察显示,加味丹参饮可以有效改善心肌IRI时心肌细胞的超微结构.结论 加味丹参饮能有效减少心肌IRI时心肌酶外漏,抑制心肌细胞凋亡,有效保护心肌细胞超微结构,这是其保护心肌IRI作用机制之一.%Objective To observe the effect of Jiawei Danshen Decoction on myocardial ischemia reperfusion injury (IRI) in blood stasis syndrome (BBS) rabbits, and investigate its mechanism.Method Sixty rabbits were randomly divided into 6 groups with 10 rabbits each: control group, BSS group, IRI group, precondition group, Danshen group and Jiawei Danshen Decoction group.BBS model of IRI was established and interfered by Jiawei Danshen Decoction.Myocardial enzyme (LDH and CK-MB) were detected by automatic biochemistry analysor.The level of cardiomyocyte apoptosis was evaluated by method of terminal deoxynucleotidy transferase mediated nick end labeling (TUNEL), and ultrastructure of myocardial cell was observed by electron microscope.Result Compared with the IRI group, both the contents of LDH and CK-MB were significantly decreased, and cardiomyocyte apoptosis was depressed significanfiy in Jiawei Danshen Decoction group (P <0.01 or P <0.05).Jiawei Danshen Decoction improved

  7. Myocardial infarction association with the Riley-Day syndrome.

    Science.gov (United States)

    Reshef, R; Aderka, D; Suprun, H; Manelis, G; Manelis, J

    1977-10-01

    The "sudden death" of a 23-year-old Ashkenazy Jew, suffering from "familial dysautonomia" was probably caused by an arrhythmia accompanying a myocardial infarction. Such a report is unique. Diffuse coronary atherosclerosis and direct myocardial "catecholamine cardiomyopathy" seem responsible for the myocardial damage. However, diversion of the endocardial blood flow toward dpicardium and a "coronary steal" phenomenon, both the result of a sudden catecholamine discharge, could aggravate the ischemic injury.

  8. Dexamethasone : Benefit and prejudice for patients undergoing on-pump coronary artery bypass grafting - A study on myocardial, pulmonary, renal, intestinal, and hepatic injury

    NARCIS (Netherlands)

    Morariu, AM; Loef, BG; Aarts, LPHJ; Rietman, GW; Rakhorst, G; van Oeveren, W; Epema, AH

    2005-01-01

    Study objectives: Cardiac surgery with cardiopulmonary bypass (CPB) results in perioperative organ damage caused by the systemic inflammatory response syndrome (SIRS) and ischemia/ reperfusion injury. Administration of corticosteroids before CPB has been demonstrated to inhibit the activation of the

  9. Dexamethasone : Benefit and prejudice for patients undergoing on-pump coronary artery bypass grafting - A study on myocardial, pulmonary, renal, intestinal, and hepatic injury

    NARCIS (Netherlands)

    Morariu, AM; Loef, BG; Aarts, LPHJ; Rietman, GW; Rakhorst, G; van Oeveren, W; Epema, AH

    2005-01-01

    Study objectives: Cardiac surgery with cardiopulmonary bypass (CPB) results in perioperative organ damage caused by the systemic inflammatory response syndrome (SIRS) and ischemia/ reperfusion injury. Administration of corticosteroids before CPB has been demonstrated to inhibit the activation of the

  10. Involvement of adenosine and standardization of aqueous extract of garlic (Allium sativum Linn.) on cardioprotective and cardiodepressant properties in ischemic preconditioning and myocardial ischemia-reperfusion induced cardiac injury

    Science.gov (United States)

    Sharma, Ashish Kumar; Munajjam, Arshee; Vaishnav, Bhawna; Sharma, Richa; Sharma, Ashok; Kishore, Kunal; Sharma, Akash; Sharma, Divya; Kumari, Rita; Tiwari, Ashish; Singh, Santosh Kumar; Gaur, Samir; Jatav, Vijay Singh; Srinivasan, Barthu Parthi; Agarwal, Shyam Sunder

    2012-01-01

    The present study investigated the effect of garlic (Allium sativum Linn.) aqueous extracts on ischemic preconditioning and ischemia-reperfusion induced cardiac injury, as well as adenosine involvement in ischemic preconditioning and garlic extract induced cardioprotection. A model of ischemia-reperfusion injury was established using Langendorff apparatus. Aqueous extract of garlic dose was standardized (0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.07%, 0.05%, 0.03%, 0.01%), and the 0.05% dose was found to be the most effective. Higher doses (more than 0.05%) were highly toxic, causing arrhythmia and cardiodepression, whereas the lower doses were ineffective. Garlic exaggerated the cardioprotective effect of ischemic preconditioning. The cardioprotective effect of ischemic preconditioning and garlic cardioprotection was significantly attenuated by theophylline (1,000 µmol/L) and 8-SPT (10 mg/kg, i.p.) and expressed by increased myocardial infarct size, increased LDH level, and reduced nitrite and adenosine levels. These findings suggest that adenosine is involved in the pharmacological and molecular mechanism of garlic induced cardioprotection and mediated by the modulation of nitric oxide. PMID:23554727

  11. Protection against myocardial ischaemia/reperfusion injury by PPAR-alpha activation is related to production of nitric oxide and endothelin-1

    DEFF Research Database (Denmark)

    Bulhak, A A; Sjöquist, P-O; Xu, C-B;

    2006-01-01

    BACKGROUND: Ligands of peroxisome proliferator-activated receptor alpha (PPAR-alpha) have been shown to reduce ischaemia/reperfusion injury. The mechanisms behind this effect are not well known. We hypothesized that activation of PPAR-alpha exerts cardioprotection via a mechanism related to nitri....... CONCLUSION: The results suggest that the PPAR-alpha activation protects the rat myocardium against ischaemia/ reperfusion injury via a mechanism related to production of NO, and possibly ET-1....

  12. 蝙蝠葛酚性碱抗兔心脑缺血再灌注损伤作用%Effect of phenolic alkaloids from Menispermum dauricum on myocardial-cerebral ischemia-reperfusion injury in rabbits

    Institute of Scientific and Technical Information of China (English)

    王芳; 曲玲; 吕青; 郭莲军

    2001-01-01

    目的:探讨蝙蝠葛酚性碱抗家兔心脑缺血再灌注损伤的作用及其机制.方法:结扎家兔左冠状动脉前降支及双侧颈总动脉,30 min后复灌,制成心脑缺血再灌模型.分别于缺血前10 min,缺血1、10、30 min,再灌1、10、30、60、120、180、240 min时经股动脉取血2 mL,再灌240 min后立即取出左心室、海马、皮层、小脑.测定血清及各组织中丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性.结果:与对照组相比,缺血再灌组(I-R)复灌10 min后血清MDA含量显著升高,而SOD活性显著降低(P<0.05).与I-R组相比,应用PAMd后,血清MDA含量降低,而SOD活性升高(P<0.05).各组织中MDA含量与SOD活性变化与血清中相似.结论:蝙蝠葛酚性碱通过减轻脂质过氧化所造成的损伤及提高SOD活性,对心脑缺血再灌注损伤具有一定的保护作用.%AIM: To explore the mechanism underlying the effect of phenolic alkaloids from Menispermum dauricum ( PAMd ) on simultaneous myocardial-cerebral ischemiareperfusion injury in rabbits. METHODS: Both left anterior descending coronary artery and bilateral carotid arteries were occluded to induce myocardial-cerebral ischemia-reperfusion injury in rabbits. At 30 min after ischemia, the occlusion was removed and shed blood was rapidly reinfused. Two mL of blood was taken from femoral artery at 10 min before ischemia, 1, 10, and 30 min after ischemia, and 1, 10, 30, 60, 120, 180, and 240 min after reperfusion. Each rabbit was sacrificed at the end of reperfusion, and left ventricle, hippocampus, cortex, and cerebellum were taken out. Malondialdehyde (MDA) content and superoxide dismutase (SOD)activity were determined. RESULTS: At 10 min after reperfusion, MDA content in serum was significantly higher and SOD activity was lower in ischemiareperfusion (Ⅰ-R) group than those of control group (P < 0.05). After administration of PAMd, MDA content was lower and SOD activity was higher in serum than those of

  13. Irreversible Processes in Inflationary Cosmological Models

    CERN Document Server

    Kremer, G M

    2002-01-01

    By using the thermodynamic theory of irreversible processes and Einstein general relativity, a cosmological model is proposed where the early universe is considered as a mixture of a scalar field with a matter field. The scalar field refers to the inflaton while the matter field to the classical particles. The irreversibility is related to a particle production process at the expense of the gravitational energy and of the inflaton energy. The particle production process is represented by a non-equilibrium pressure in the energy-momentum tensor. The non-equilibrium pressure is proportional to the Hubble parameter and its proportionality factor is identified with the coefficient of bulk viscosity. The dynamic equations of the inflaton and the Einstein field equations determine the time evolution of the cosmic scale factor, the Hubble parameter, the acceleration and of the energy densities of the inflaton and matter. Among other results it is shown that in some regimes the acceleration is positive which simulate...

  14. Mathematical models and equilibrium in irreversible microeconomics

    Directory of Open Access Journals (Sweden)

    Anatoly M. Tsirlin

    2010-07-01

    Full Text Available A set of equilibrium states in a system consisting of economic agents, economic reservoirs, and firms is considered. Methods of irreversible microeconomics are used. We show that direct sale/purchase leads to an equilibrium state which depends upon the coefficients of supply/demand functions. To reach the unique equilibrium state it is necessary to add either monetary exchange or an intermediate firm.

  15. Multiscale multifractal time irreversibility analysis of stock markets

    Science.gov (United States)

    Jiang, Chenguang; Shang, Pengjian; Shi, Wenbin

    2016-11-01

    Time irreversibility is one of the most important properties of nonstationary time series. Complex time series often demonstrate even multiscale time irreversibility, such that not only the original but also coarse-grained time series are asymmetric over a wide range of scales. We study the multiscale time irreversibility of time series. In this paper, we develop a method called multiscale multifractal time irreversibility analysis (MMRA), which allows us to extend the description of time irreversibility to include the dependence on the segment size and statistical moments. We test the effectiveness of MMRA in detecting multifractality and time irreversibility of time series generated from delayed Henon map and binomial multifractal model. Then we employ our method to the time irreversibility analysis of stock markets in different regions. We find that the emerging market has higher multifractality degree and time irreversibility compared with developed markets. In this sense, the MMRA method may provide new angles in assessing the evolution stage of stock markets.

  16. Iloprost reduces myocardial edema in a rat model of myocardial ischemia reperfusion.

    Science.gov (United States)

    Caliskan, A; Yavuz, C; Karahan, O; Yazici, S; Guclu, O; Demirtas, S; Mavitas, B

    2014-05-01

    Myocardial ischemia severely reduces myocyte longevity and function. Extensive interstitial edema and cell damage occur as a result of myocardial reperfusion injury. Current therapies are directed at prevention of ischemia-induced damage to cardiac tissue. Iloprost is a novel pharmaceutical agent for the treatment of ischemia. Twenty rats were segregated into four experimental groups. The procedure control group consisted of four rats undergoing a sham operation. The remaining 16 rats were divided into two equal groups. The first group (control group) received a continuous intravenous infusion of physiological serum immediately prior to the procedure. Iloprost was administered by a continuous intravenous infusion into the right jugular vein at an infusion rate of 100 ng/kg/min for 30 minutes prior to reperfusion in the experimental group (study group). Following the infusion treatments, ligation of the left coronary artery was conducted for 30 minutes to induce myocardial ischemia. The rats were euthanized 24 hours after reperfusion and cardiac tissue was harvested from all specimens for analysis. Histological examination revealed three myocardial tissue specimens with grade II damage and five myocardial tissue specimens with grade III reperfusion injury in the control group. However, the study group consisted of two grade III myocardial tissue specimens, five grade II myocardial tissue specimens and one grade I myocardial tissue specimen. Moreover, a statistically significant reduction in myocardial edema was observed in the study group (p=0.022). Our results support the hypothesis that iloprost enhances protection against cardiac ischemia reperfusion injury. This protective effect may be associated with vasodilation, antioxidant or anti-edema mechanisms.

  17. 硫化氢对大鼠骨骼肌缺血再灌注所致心肌损伤的保护作用%Exogenous hydrogen sulfide prevents myocardial injury following skeletal muscle ischemia reperfusion

    Institute of Scientific and Technical Information of China (English)

    陈雯; 张颖; 齐迎春; 任青爱; 杨靖; 邓昭阳; 谢晓华

    2011-01-01

    目的 研究外源性硫化氢(H2S)对大鼠骨骼肌缺血再灌注后心肌损伤的保护作用.方法 选雄性Wistar大鼠31只,随机分为4组:(1)正常对照组(8只);(2)缺血再灌注组(8只),应用止血带结扎构建大鼠双下肢缺血再灌注模型,缺血4 h再灌注4 h;(3)硫氢化钠(NaHS)组(8只),缺血前及再灌注前腹腔注射NaHS 0.78 mg/kg;(4)炔丙基甘氨酸(PPG)组(7只),缺血前及再灌注前腹腔注射PPG 50 mg/kg.观察各组心肌病理、血浆H2S、肌酸激酶同工酶(CK-MB)、肌钙蛋白T(TnT)及心肌胱硫醚-γ-裂解酶(CSE)活性的变化.结果 与正常对照组比较,缺血再灌注组血浆H2S及心肌CSE活性明显下降,血浆CK-MB、TnT明显升高(P<0.05).与缺血再灌注组比较,NaHS组血浆H2S浓度升高59%(P<0.05),心肌CSE活性升高93%(P<0.05),血浆CK-MB降低29%(P<0.05),血浆TnT降低67%(P<0.05);PPG组血浆H2S浓度下降20%,但无统计学差异,心肌CSE活性降低38%(P<0.05),血浆心肌酶学改变无统计学差异.心肌病理提示,缺血再灌注组心肌明显肿胀、血管充血,心肌细胞间可见明显分叶核粒细胞浸润,红细胞漏出增多,NaHS组干预后心肌损伤明显减轻.结论 外源性H2S补充可以减轻骨骼肌缺血再灌注所致的心肌损伤.%Objective To explore the role of exogenous hydrogen sulfide (H2S)in the treatment of the myocardial injury following skeletal muscle ischemia reperfusion (IR).Methods We have established the model of bilateral hindlimb IR in rats by using a tourniquet.Thirty-one Wistar rats were divided into 4 groups randomly: ①Group normal (C), ②Group IR :4 hours reperfusion following 4 hours ischemia, ③Group NaHS:IR+NaHS 0.78mg/kg ip, ④ Group PPG:IR+DL-propargylglycine (PPG)50 mg/kg ip.The pathologic changes in the myocardium were observed.The plasma levels of H2S,CK-MB ,TNT and the CSE activity in myocardium in each group were measured.Results Histopathologic results indicated significant myocardial

  18. 脓毒症早期炎症因子变化与心肌损伤的相关性研究%Correlation between inflammatory cytokines and myocardial injury in early stages of sepsis

    Institute of Scientific and Technical Information of China (English)

    李登辉; 胡德林; 李亚南; 台运成; 方林森; 余又新; 王春华

    2014-01-01

    Objective To study the correlation between inflammatory cytokines of serum and myocardial injury in the early stages of septic rats.Methods Seventy-two female clean SD rats were divided into sham operation group(n =36)and sepsis group(n =36)random-ly,and the two groups were performed exploratory surgery and cecum ligation and puncture(CLP)separately.Each group was taken to measure the serum levels of TNF-αand cTnI through abdominal aortic blood at 3,9,24,36,48 and 72 h.Results The level of serum TNF-αand IL-1 peaked at 3 h,then gradually decreased,which were still significantly higher than those of sham operation group(P <0.05);the level of ser-um of cTnI peaked at 3 h,then gradually decreased,which were still significantly higher than those of sham operation group(P <0.05);the levels of serum IL-1 and TNF-α had a significant positive correlation with the serum levels of cTnI in the early stage of sepsis.Conclusion The elevated serum levels of inflammatory cytokines have a positive correlation with myocardial injury in the early stages of sep-sis.This can be used as an important indicator of early sepsis detection and diagnosis of myocardial injury.%目的:研究脓毒症大鼠早期血清中炎性因子与心肌损伤之间的相关性。方法72只雌性清洁级 SD 大鼠随机分为假手术组(n =36)和脓毒症组(n =36),分别行盲肠探查术、盲肠结扎穿孔术,均于术后3、9、24、36、48和72 h 采腹主动脉血检测肌钙蛋白 I(cTnI)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)水平。结果TNF-α、IL-1于3 h 达峰值,后逐渐降低,均高于假手术组(P <0.05);cTnI 于3 h 达峰值,后逐渐降低,均高于假手术组(P <0.05);血清 TNF-α、IL-1均与 cTnI 呈显著正相关。结论脓毒症早期炎症因子的升高与心肌损伤具有正相关性,可作为检测和诊断早期脓毒症心肌损伤的重要指标。

  19. B lymphocytes trigger monocyte mobilization and impair heart function after acute myocardial infarction

    Science.gov (United States)

    Zouggari, Yasmine; Ait-Oufella, Hafid; Bonnin, Philippe; Simon, Tabassome; Sage, Andrew P; Guérin, Coralie; Vilar, José; Caligiuri, Giuseppina; Tsiantoulas, Dimitrios; Laurans, Ludivine; Dumeau, Edouard; Kotti, Salma; Bruneval, Patrick; Charo, Israel F; Binder, Christoph J; Danchin, Nicolas; Tedgui, Alain; Tedder, Thomas F; Silvestre, Jean-Sébastien; Mallat, Ziad

    2014-01-01

    Acute myocardial infarction is a severe ischemic disease responsible for heart failure and sudden death. Here, we show that after acute myocardial infarction in mice, mature B lymphocytes selectively produce Ccl7 and induce Ly6Chi monocyte mobilization and recruitment to the heart, leading to enhanced tissue injury and deterioration of myocardial function. Genetic (Baff receptor deficiency) or antibody-mediated (CD20- or Baff-specific antibody) depletion of mature B lymphocytes impeded Ccl7 production and monocyte mobilization, limited myocardial injury and improved heart function. These effects were recapitulated in mice with B cell–selective Ccl7 deficiency. We also show that high circulating concentrations of CCL7 and BAFF in patients with acute myocardial infarction predict increased risk of death or recurrent myocardial infarction. This work identifies a crucial interaction between mature B lymphocytes and monocytes after acute myocardial ischemia and identifies new therapeutic targets for acute myocardial infarction. PMID:24037091

  20. Optimized Heart Sampling and Systematic Evaluation of Cardiac Therapies in Mouse Models of Ischemic Injury: Assessment of Cardiac Remodeling and Semi-Automated Quantification of Myocardial Infarct Size.

    Science.gov (United States)

    Valente, Mariana; Araújo, Ana; Esteves, Tiago; Laundos, Tiago L; Freire, Ana G; Quelhas, Pedro; Pinto-do-Ó, Perpétua; Nascimento, Diana S

    2015-12-02

    Cardiac therapies are commonly tested preclinically in small-animal models of myocardial infarction. Following functional evaluation, post-mortem histological analysis is essential to assess morphological and molecular alterations underlying the effectiveness of treatment. However, non-methodical and inadequate sampling of the left ventricle often leads to misinterpretations and variability, making direct study comparisons unreliable. Protocols are provided for representative sampling of the ischemic mouse heart followed by morphometric analysis of the left ventricle. Extending the use of this sampling to other types of in situ analysis is also illustrated through the assessment of neovascularization and cellular engraftment in a cell-based therapy setting. This is of interest to the general cardiovascular research community as it details methods for standardization and simplification of histo-morphometric evaluation of emergent heart therapies. © 2015 by John Wiley & Sons, Inc. Copyright © 2015 John Wiley & Sons, Inc.

  1. Protective effect of sesamin against myocardial injury induced by cadmium chloride in rats%芝麻素对氯化镉心肌损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    田俊芝; 张荣; 张宏学; 刘诣; 牛玉杰; 赵丽娟; 王璐琪; 郭会彩

    2014-01-01

    Objective To investigate the protective effect of sesamin against cadmium chloride (CdC12)-induced cardiotoxicity in rats.Methods Fifty male Wistar rats were randomly assigned to five groups:control group,CdC12 group,and low-,middle-,and high-dose sesamin groups.The control group was given normal saline.The CdC12 group and sesamin groups were intraperitoneally injected with CdCl2 (5 mg/kg·2 d),and the low-,middle-,and high-dose sesamin groups were given 20,40,and 80 mg/kg sesamin,respectively.All treatments lasted for four weeks.ECG was measured by a physiological recorder,and serum myocardial enzyme levels were determined by biochemical assay.The heart was weighed,and heart tissues were used in histopathological examination and determination of malondialdehyde (MDA) level.Results Compared with the control group,the CdC12 group showed significantly higher levels of serum CK and CK-MB,an increased heart coefficient,significant ST-segment elevation,and higher level of MDA in myocardial tissue (P <0.05).Histopathological analysis showed edema of myocardial tissues and cells,myocardial fibers disorder,karyopyknosis,and uneven or deep staining of nuclear chromatin.Different doses of sesamin relieved the myocardial pathological changes induced by CdCl2,and high-dose sesamin was the most effective.The middleand high-dose sesamin groups showed significantly reduced serum CK and CK-MB levels compared with the CdC12 group (P<0.05).The heart coefficient of the high-dose sesamin group (0.19±0.01%) was significantly lower than that of the CdCl2 group (0.21 ±0.01%) (P<0.05).Myocardial M DA levels of the three sesamin groups (42.32±4.65,36.71 ±5.34,and 33.12±4.62 nmol/mg pro,respectively) were all significantly lower than that of the CdC12 group (55.87±3.65 nmol/mg pro) (P<0.05).Conclusion Sesamin can relieve myocardial injury induced by CdCl2,and one possible mechanism is the enhancement of antioxidant capacity of myocardial tissue.%目的 观察芝麻素对

  2. Sca-1+ cardiosphere-derived cells are enriched for Isl1-expressing cardiac precursors and improve cardiac function after myocardial injury.

    Directory of Open Access Journals (Sweden)

    Jianqin Ye

    Full Text Available BACKGROUND: Endogenous cardiac progenitor cells are a promising option for cell-therapy for myocardial infarction (MI. However, obtaining adequate numbers of cardiac progenitors after MI remains a challenge. Cardiospheres (CSs have been proposed to have cardiac regenerative properties; however, their cellular composition and how they may be influenced by the tissue milieu remains unclear. METHODOLOGY/PRINCIPAL FINDING: Using "middle aged" mice as CSs donors, we found that acute MI induced a dramatic increase in the number of CSs in a mouse model of MI, and this increase was attenuated back to baseline over time. We also observed that CSs from post-MI hearts engrafted in ischemic myocardium induced angiogenesis and restored cardiac function. To determine the role of Sca-1(+CD45(- cells within CSs, we cloned these from single cell isolates. Expression of Islet-1 (Isl1 in Sca-1(+CD45(- cells from CSs was 3-fold higher than in whole CSs. Cloned Sca-1(+CD45(- cells had the ability to differentiate into cardiomyocytes, endothelial cells and smooth muscle cells in vitro. We also observed that cloned cells engrafted in ischemic myocardium induced angiogenesis, differentiated into endothelial and smooth muscle cells and improved cardiac function in post-MI hearts. CONCLUSIONS/SIGNIFICANCE: These studies demonstrate that cloned Sca-1(+CD45(- cells derived from CSs from infarcted "middle aged" hearts are enriched for second heart field (i.e., Isl-1(+ precursors that give rise to both myocardial and vascular tissues, and may be an appropriate source of progenitor cells for autologous cell-therapy post-MI.

  3. Effect of Tanshinone Ⅱ A pretreatment on myocardial ischemia/reperfusion injury in rats%丹参酮ⅡA预处理对大鼠心肌缺血再灌注损伤的作用研究

    Institute of Scientific and Technical Information of China (English)

    吴晓倩; 何丽姗

    2012-01-01

    目的 探讨丹参酮ⅡA对大鼠心肌缺血再灌注损伤的作用.方法 雄性SD大鼠随机分为假手术组、模型组、丹参酮ⅡA预处理组,后两组进行冠状动脉左前降支结扎30 min后再灌注120 min.期间全程监测心率和血流动力学指标.实验结束后取心脏做TTC染色及HE染色,观察心肌梗死面积和组织学改变.结果 模型组大鼠心脏功能明显下降并发生心肌梗死提示造模成功.与模型组比较,丹参酮ⅡA组在缺血30 min,再灌注30、60、120 min各时间点,左心室收缩末压、左室内压最大上升及下降速率明显增高、心率基本恢复正常.组织学染色显示,与模型组比较,丹参酮ⅡA组心肌梗死区面积降低、心肌细胞变性坏死程度明显减轻.结论 丹参酮ⅡA预处理对大鼠心肌缺血再灌注损伤具有保护作用.%Objective To investigate the effect of Tanshinone II A on myocardial ischemia/reperfusion injury in rats. Methods Male SD rats were randomized to Sham operated group, ischemia/reperfusion (I/R) group and Tanshinone fl A group. Rats in I/R group and Tanshinone II A group were subjected to legation of left anterior descending coronary artery for 30 minutes and 120 min of reperfusion. The hemodynamics were monitored during the whole process. TTC and HE staining were performed to examine the infarct size and the histology of hearts. Result Compared with I/R group, the cardiac hemodynamics were significantly improved after Tanshinone II A pretreatment, and Tanshinone H A reduced the infarct size significantly compared with I/R group. Conclusion Tanshinone II A pretreatment exerted protection against myocardial ischemia/reperfusion injury.

  4. Exosomes and cardiac repair after myocardial infarction.

    Science.gov (United States)

    Sahoo, Susmita; Losordo, Douglas W

    2014-01-17

    Myocardial infarction is a leading cause of death among all cardiovascular diseases. The analysis of molecular mechanisms by which the ischemic myocardium initiates repair and remodeling indicates that secreted soluble factors are key players in communication to local and distant tissues, such as bone marrow. Recently, actively secreted membrane vesicles, including exosomes, are being recognized as new candidates with important roles in intercellular and tissue-level communication. In this review, we critically examine the emerging role of exosomes in local and distant microcommunication mechanisms after myocardial infarction. A comprehensive understanding of the role of exosomes in cardiac repair after myocardial infarction could bridge a major gap in knowledge of the repair mechanism after myocardial injury.

  5. An action principle of classical irreversible thermodynamics - Irreversible thermodynamic cycles and embodied bits of information

    CERN Document Server

    Hanel, Rudolf A

    2016-01-01

    Despite its simplicity, it seems to my best of knowledge that the possibly simplest approach towards deriving equations governing irreversible thermodynamics from gas-kinetic considerations within the framework of classical mechanics has never been pursued. In this paper we address this omission and derive the equations describing the irreversible thermodynamics of a gas in a piston and associated thermodynamic cycles performed in finite time. What we find is a thermodynamic action principle: The irreversible work we require for performing a thermodynamic cycle in finite time times the time we require to run through the cycle, a isothermal compression/decompression cycle for instance, will always be larger or equal to a lower bound given by a system specific constant with the dimension of an action. This process specific action constants can take values of the order of Plank's constant for microscopic processes, such as displacing a Hydrogen atom by one atom diameter. For macroscopic processes (e.g. a bicycle...

  6. Chaos and irreversibility in simple model systems.

    Science.gov (United States)

    Hoover, Wm. G.; Posch, Harald A.

    1998-06-01

    The multifractal link between chaotic time-reversible mechanics and thermodynamic irreversibility is illustrated for three simple chaotic model systems: the Baker Map, the Galton Board, and many-body color conductivity. By scaling time, or the momenta, or the driving forces, it can be shown that the dissipative nature of the three thermostated model systems has analogs in conservative Hamiltonian and Lagrangian mechanics. Links between the microscopic nonequilibrium Lyapunov spectra and macroscopic thermodynamic dissipation are also pointed out. (c) 1998 American Institute of Physics.

  7. Irreversibility for all bound entangled states

    CERN Document Server

    Yang, D; Horodecki, R; Synak-Radtke, B; Yang, Dong; Horodecki, Michal; Horodecki, Ryszard; Synak-Radtke, Barbara

    2005-01-01

    We derive a new inequality for entanglement for a mixed four-partite state. Employing this inequality, we present a one-shot lower bound for entanglement cost and prove that entanglement cost is strictly larger than zero for any entangled state. We demonstrate that irreversibility occurs in the process of formation for all non-distillable entangled states. In this way we solve a long standing problem, of how "real" is entanglement of bound entangled states. Using the new inequality we also prove impossibility of local-cloning and local-deleting of a known entangled state.

  8. Role of anesthetics in protecting the heart against myocardial ischemia-reperfusion injury%麻醉药物对心肌缺血再灌注损伤的保护研究进展

    Institute of Scientific and Technical Information of China (English)

    刘保江; 郭志佳

    2008-01-01

    心肌缺血再灌注损伤(MIRI)是临床上一类非常常见而严重的并发症,被麻醉学界广泛关注.实际上,自从1985年Freedman首次报道安氟醚能改善缺血后心功能以来,如何找到防治MIRI经济有效的方法,已经成为这个领域多年来研究的方向.大量实验证明,多种麻醉药物对MIRI具有不同方面的保护作用.此文综述了国内外关于麻醉药物以及具有中国特色和优势的中药复方制剂对MIRI保护研究的进展,其中重点综述几种代表性药物,如瑞芬太尼、丙泊酚、咪达唑仑、参附注射液等,并总结了近年来这一方向的研究成果.%Cardiac injury following ischemia-reperfusion cgn lead to miocardial cell death and result in cardiac dysfunction.A wide railge of cardiae factors have been studied now.This review aims to provide an overview of current data on the role of anesthetics,such as isoflurane,sufentanil,propofol,midazolam,especially Shenfu injection,on proteting against myocardial ischemia reperfusion injury.

  9. 芬太尼预处理对兔心肌缺血再灌注后心肌梗死范围及心功能的影响%Effects of pretreatment with fentanyl on myocardial infarction size and cardiac function in rabbits with acute myocardial ischemia reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    郑向明; 孟凡民; 王春亭

    2012-01-01

    Objective To study the myocardial protective effect of pretreatment with fentanyl on rabbits with acute myocardial ischemia reperfusion injury.Methods Twenty-four male New Zealand White rabbits were randomly divided into 3 groups:group C ( acute myocardial ischemia reperfusion injury group),group F ( fentanyl group) and group N-F ( naloxone-fentanyl group),with 8 cases in each group.All rabbits experienced 30 min of regional ischemia through the occlusion of the left anterior descending coronary artery( LAD),followed by 120 min of reperfusion.The rabbits in C group were only subjected to the above ischemia/reperfusion (I/R) sequence.The rabbits in Group F were intravenously injected with fentany1 0.15 mg/kg at 15 minutes before the coronary occlusion.The rabbits in Group N-F were intravenously injected with naloxone 3 mg/kg,followed by 70 μg/(kg · min) infusion before reperfusion and were intravenously injected with fentanyl 0.15 mg/kg at 15 min before myocardial ischemia.Heart rate(HR),left ventricular systolic pressure( LVSP),left ventricular end diastolic pressure( LVEDP),maximum positive and minimum negative left ventricular pressure derivatives ( + dp/dt and-dp/dt) were continuously monitored and recorded at baseline ( T0 ),30 min after ischemia( T1 ),and 10 min ( T2 ),30 min(T3 ),120 min(T4) after reperfusion during I/R process.After 120 min reperfusion,hearts were removed for the measurement of myocardial ischemia and infarction size.Results Compared with the baseline(T0),LVSP,± dp/dt decreased whereas LVEDP increased significantly during T1-T4 (P <0.05 ).There were no significant differences in homodynamic parameters between group C and group N F ( P > 0.05 ).In F group,the LVSP and + dp/dt were significantly higher than those of group C and group N-F after 30 min in reperfusion ( P < 0.05 ) and the infarction size and weight were smaller (P <0.01 ).Conclusions Pretreatment with fentanyl has protective effect against ischemia/reperfusion injury

  10. 高迁移率族蛋白B1对心肌缺血再灌注损伤保护作用的初步临床研究%Cardioprotective effect of high mobility group protein B1 against myocardial ischemia-reperfusion injury in acute myocardial infarction patients

    Institute of Scientific and Technical Information of China (English)

    刘宇; 曹清心; 张燕; 赵仙先

    2012-01-01

    目的 随着急性心肌梗死(acute myocardial infarction,AMI)发病率的不断增加,以及再灌注治疗的广泛开展,缺血再灌注损伤(ischemical reperfusion injury,IRI)已经引起了广泛关注,但尚未找到一种能有效减轻IRI的治疗方法.近年来,国内外基于动物模型的研究发现:高迁移率族蛋白B1(high mobility group box 1 protein,HMGB1)可能在IRI过程中发挥着中枢作用,并且目前有关AMI患者经经皮冠状动脉内介入术(percutaneous coronary intervention,PCI)血浆中HMGB1浓度变化及其机制的研究还鲜见报道.文中初步探讨HMGB1是否参与AMI患者PCI中心肌IRI过程,及其在此过程中产生的心肌保护作用和可能机制.方法 采用酶联免疫吸附法,分别测定17例经冠状动脉造影术(coronary arteriography,CAG)检查正常的健康志愿者(对照组),41例AMI经急诊PCI治疗患者(AMI手术组)术前即刻、术后24h和48h血浆中HMGB1和血管内皮生长因子(vascular endothelial growth factor,VEGF)变化水平,并记录AMI手术组梗死相关血管(infarction related artery,IRA)开通即刻出现的再灌注心律失常(reperfusion arrhythmia,RA)类型、术后24h脑钠肽(brain natriuretic peptide,BNP)水平、住院期间不良临床事件(心力衰竭、心源性猝死)及其他基本临床数据.结果 AMI手术组患者在IRA开通即刻均观察到RA;术后24h HMGB1水平明显高于术前即刻及术后48h(P<0.05),并且各时间点HMGB1水平与VEGF水平呈正相关(P<0.05);AMI手术组院内出现不良临床事件与无不良事件的患者相比较,各时间点HMGB1水平明显降低(P<0.05).结论 HMGB1参与了AMI患者行PCI手术中IRI的过程;HMGB1水平对于AMI患者的远期预后有一定预测作用;HMGB1可能通过促进VEGF的分泌而参与梗死后心肌的修复过程,并可能通过此作用对改善心功能、保护心肌细胞产生一定作用.%Objective With the increasing incidence of acute myocardial infarction

  11. The protective effect of trimetazidine on the myocardial ischemia-reperfusion injury in rats%曲美他嗪对大鼠心肌缺血-再灌注损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    颜永进; 张跃明; 陆洋; 王世亚

    2011-01-01

    目的 探讨曲美他嗪(TMZ)对缺血一再灌注(I-R)后大鼠心肌细胞凋亡的保护作用.方法 SD 大鼠随机分为假手术组(A组)、I-R组(B组)、低浓度TMZ(1 ml/100 g)组(C组)和高浓度TMZ(3 ml/100 g)组(D组),每组6只.制备大鼠心肌I-R模型,采用流式细胞仪(FCM)、原位末端标记(TUNEL)技术、免疫组化检测心肌组织细胞凋亡情况,并观察细胞形态变化.结果 B组细胞凋亡指数、TUNEL 阳性细胞数、Bel-2、Bax较A组增高[(0.2416±0.0263)vs.(0.0469±0.0136),(3.213±0.14)vs.(0.44±0.133),(2.057±0.187)vs.(0.47±0.082),(4.257±0.135)VS.(0.52±0.058)(P<0.05)],而C、D组细胞凋亡指数、TUNEL阳性细胞数、Bax明显下降(P<0.05),D组减低更明显.结论 TMZ可抑制心肌I-R损伤中细胞凋亡.%Objective To investigate the protective effect of trimethazine (TMZ) on rat myocardial cell apoptosis after ischemia-reperfusion (IR). Methods Twenty-four SD rats were randomly and equally divided into 4 groups of A(sham operated),B(I-R model),C(treated with TMZ 1 ml/100 g) and D(treated with TMZ 3 ml/100 g). The myocardial I-R model in rats was established.The myocardial cell apoptosis was respectively detected by flow cytometry (FCM), TUNEL technology and immunohistochemistry, and the changes of cell morphology were observed by microscope. Results The apoptotic index, the positive cell number and the levels of Bcl-2 and Bax were higher in group B than those in group A[(0. 2416±0. 0263) vs. (0. 0469±0. 0136), (3. 213± 0. 140) vs. (0. 440±0. 133), (2. 057±0. 187) vs. (0. 470±0. 082), (4. 257±0. 135) vs. (0. 520± 0. 058)](P<0. 05) ,which were much lower in groups of C and D(P<0. 05). Conclusion TMZ can inhibit cell apoptosis during myocardial I-R, which in turn attenuates I-R injury.

  12. 匹伐他汀对大鼠心肌缺血再灌注损伤的保护作用%The Positive Role of Pitavastatin in Prevention of Ischemia-reperfusion Myocardial Injury

    Institute of Scientific and Technical Information of China (English)

    尤杨; 冯倩; 夏岳; 戚国庆; 杨志瑜

    2015-01-01

    group.The levels of CK-MB were discerned after operation.Triphenyl tetrazolium chloride and Evans blue double staining meth-od was used to determinat the myocardial infarct size and ischemic area in each experimental group.Result:The levels of CK-MB in control group and experimental group elevated significantly compared with Sham group(P0.05).But when it comes to infarct size, it was more smaller in Statin group(P<0.05).Conclusion:Pitavastatin could reduce the cardiac infarct area and alleviate myocardial ischemia-reperfusion injury.

  13. Towards myocardial contraction force image reconstruction for heart disease assessment and intervention planning

    Science.gov (United States)

    Haddad, Seyyed M. H.; Drangova, Maria; White, James A.; Samani, Abbas

    2015-03-01

    It is clinically vital to devise a technique to evaluate regional functionality of the myocardium in order to determine the extent and intensity of local damage to the cardiac tissue caused by ischemic injuries. Such a technique can potentially enable cardiologists to discriminate between reversible and irreversible ischemic injuries and to devise appropriate revascularization therapy in case of reversible lesions. The technique is founded on the premise that sufficient contraction force generated by the cardiac tissue can be regarded as a direct and reliable criterion for regional analysis of tissue healthy functionality. To this end, a number of imaging techniques have been developed and, to our knowledge, none of them assess regional cardiac functionality based on a straightforward mechanical measure such as local cardiac contraction forces. . As such, a novel imaging technique is being developed on the basis of quantification and visualisation of local myocardial contraction forces. In this technique, cardiac contraction force distribution is attained through solving an inverse problem within an optimization framework which uses iterative forward mechanical modelling of the myocardium. Hence, a forward mechanical model of the myocardium which is computationally efficient, robust, and adaptable to diverse pathophysiological conditions is necessary for this development. As such, this paper is geared towards developing a novel mechanical model of the healthy and pathological myocardium which considers all aspects of the myocardial mechanics including hyperelasticity, anisotropy, and active contraction force. In this investigation, two major parts, including background tissue and reinforcement bars (fibers) have been considered for modelling the myocardium. The model was implemented using finite element (FE) approach and demonstrated very good performance in simulating normal and infarcted left ventricle (LV) contractile function.

  14. 山莨菪碱对心脏瓣膜置换术中心肌再灌注损伤的作用%Effect of Anisodamine on Myocardial Reperfusion Injury

    Institute of Scientific and Technical Information of China (English)

    刘贵明; 丁学琴; 许国忠; 王俊科; 盛卓人

    2001-01-01

    Objective: Our purpose was to study the effect of anisodamine on the injury of myocardium after myocardial ischemia reperfusion. Methods: Eighteen patients (ASA grade Ⅱto Ⅲ) scheduled for valve replacement, were randomly divided into 2 groups during extracorporeal circulation. Anisodamine (0.25 mg/kg) was given intravenously in the anisodamine group before reperfusion. Equivalent volumes of normal saline were administered in the control group. The central venous blood samples were collected at different time after ischemia and reperfusion. We then measured the concentrations of lactic dehydrogenase (LDH), creatine kinase (CK), and malondiadehyde (MDA) with biochemical methods. Results: The levels of serum LDH, CK, and plasma MDA increased significantly in the control group during ischemia and reperfusion. In the anisodamine group, the levels of serum LDH and CK increased. But the values were lower at corresponding time than those in the control group (P0.05);体外循环后心功能恢复情况观察组好于对照组。结论:再灌注前给予山莨菪碱可在一定程度上减轻心肌再灌注损伤,临床上有一定的应用价值。

  15. 心脏肥大细胞在心肌缺血/再灌注损伤中的研究进展%Cardiac mast cells in myocardial ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    张江玲; 陈杰; 王祥瑞

    2010-01-01

    Mast cells are multifunctional effector cells and originate from stem cells in the bone marrow. After being activated, it degranulates and releases several kind of inflammation mediators, (eg. cytokines and proteases) participating in inflammatory reaction and IgE-dependent histamine-mediated hypersusceptibility reaction. This article discusses the relationship between cardiac mast cells and the pathological progress such as inflammatory reaction、cell apoptosis and infarct recovery in myocardial ischemia-reperfusion injury.%肥大细胞是一种多效应细胞,起源于骨髓多分化细胞,激活后脱颗粒释放多种炎症介质、细胞因子及蛋白酶,参与炎症反应及IgE依赖的组胺介导的高敏反应.现讨论心脏肥大细胞与心肌缺血/再灌注(ischemia/reperfusion,I/R)损伤中炎症反应、细胞凋亡及梗死修复等病理过程的相关关系.

  16. Irreversibility-inversions in 2D turbulence

    Science.gov (United States)

    Bragg, Andrew; de Lillo, Filippo; Boffetta, Guido

    2016-11-01

    We consider a recent theoretical prediction that for inertial particles in 2D turbulence, the nature of the irreversibility of their pair dispersion inverts when the particle inertia exceeds a certain value. In particular, when the particle Stokes number, St , is below a certain value, the forward-in-time (FIT) dispersion should be faster than the backward-in-time (BIT) dispersion, but for St above this value, this should invert so that BIT becomes faster than FIT dispersion. This non-trivial behavior arises because of the competition between two physically distinct irreversibility mechanisms that operate in different regimes of St . In 3D turbulence, both mechanisms act to produce faster BIT than FIT dispersion, but in 2D, the two mechanisms have opposite effects because of the inverse energy cascade in the turbulent velocity field. We supplement the qualitative argument given by Bragg et al. by deriving quantitative predictions of this effect in the short-time dispersion limit. These predictions are then confirmed by results of inertial particle dispersion in a direct numerical simulation of 2D turbulence.

  17. Probabilistic Gompertz model of irreversible growth.

    Science.gov (United States)

    Bardos, D C

    2005-05-01

    Characterizing organism growth within populations requires the application of well-studied individual size-at-age models, such as the deterministic Gompertz model, to populations of individuals whose characteristics, corresponding to model parameters, may be highly variable. A natural approach is to assign probability distributions to one or more model parameters. In some contexts, size-at-age data may be absent due to difficulties in ageing individuals, but size-increment data may instead be available (e.g., from tag-recapture experiments). A preliminary transformation to a size-increment model is then required. Gompertz models developed along the above lines have recently been applied to strongly heterogeneous abalone tag-recapture data. Although useful in modelling the early growth stages, these models yield size-increment distributions that allow negative growth, which is inappropriate in the case of mollusc shells and other accumulated biological structures (e.g., vertebrae) where growth is irreversible. Here we develop probabilistic Gompertz models where this difficulty is resolved by conditioning parameter distributions on size, allowing application to irreversible growth data. In the case of abalone growth, introduction of a growth-limiting biological length scale is then shown to yield realistic length-increment distributions.

  18. The effect of metformin on the myocardial tolerance to ischemia-reperfusion injury in the rat model of diabetes mellitus type II.

    Science.gov (United States)

    Kravchuk, Ekaterina; Grineva, Elena; Bairamov, Alekber; Galagudza, Michael; Vlasov, Timur

    2011-01-01

    In recent years, evidence has been accumulated that metformin, an antidiabetic drug in the biguanide class, in addition to its well-recognized glucose-lowering effect, can also reduce cardiovascular mortality in the patients with type 2 diabetes mellitus (T2DM). Besides, there are a few experimental studies on the possibility of the direct anti-ischemic effect of the drug in both type 1 diabetes mellitus and T2DM. In our study, myocardial tolerance to ischemia in rats with neonatal streptozotocin T2DM was investigated using the model of global ischemia-reperfusion of the isolated perfused heart. Metformin was administered i.p. at a dose of 200 mg/kg/day for 3 days prior to isolated heart perfusion. The results showed that both the infarct size and postischemic recovery of left ventricular function were not different between controls and metformin-treated animals. At the same time, the infarct size in the T2DM animals was significantly lower than that in the controls (24.4 ± 7.6% versus 45.0 ± 10.4%, resp., P < .01), indicative of the metabolic preconditioning in T2DM. It follows that the protocol of metformin administration used in this study had not elicited cardioprotective effect in animals with T2DM so that the different mechanism(s) may underlie the beneficial effect of metformin on cardiovascular complications in patients with T2DM which, however, would need further investigation.

  19. The Effect of Metformin on the Myocardial Tolerance to Ischemia-Reperfusion Injury in the Rat Model of Diabetes Mellitus Type II

    Directory of Open Access Journals (Sweden)

    Ekaterina Kravchuk

    2011-01-01

    Full Text Available In recent years, evidence has been accumulated that metformin, an antidiabetic drug in the biguanide class, in addition to its well-recognized glucose-lowering effect, can also reduce cardiovascular mortality in the patients with type 2 diabetes mellitus (T2DM. Besides, there are a few experimental studies on the possibility of the direct anti-ischemic effect of the drug in both type 1 diabetes mellitus and T2DM. In our study, myocardial tolerance to ischemia in rats with neonatal streptozotocin T2DM was investigated using the model of global ischemia-reperfusion of the isolated perfused heart. Metformin was administered i.p. at a dose of 200 mg/kg/day for 3 days prior to isolated heart perfusion. The results showed that both the infarct size and postischemic recovery of left ventricular function were not different between controls and metformin-treated animals. At the same time, the infarct size in the T2DM animals was significantly lower than that in the controls (24.4 ± 7.6% versus 45.0 ± 10.4%, resp., P<.01, indicative of the metabolic preconditioning in T2DM. It follows that the protocol of metformin administration used in this study had not elicited cardioprotective effect in animals with T2DM so that the different mechanism(s may underlie the beneficial effect of metformin on cardiovascular complications in patients with T2DM which, however, would need further investigation.

  20. The Value of Fighting Irreversible Demise by Softening the Irreversible Cost

    NARCIS (Netherlands)

    Magis, P.; Sbuelz, A.

    2005-01-01

    We study a novel issue in the real-options-based technology innovation literature by means of double barrier contingent claims analysis.We show how much a ¯rm with the monopoly over a project is willing to spend in investment technology innovation that softens the irreversible cost of accessing the

  1. Myocardial protection from ischemia-reperfusion injury by Salvianolic acid A in rats%丹酚酸A对缺血/再灌注心肌的保护作用研究

    Institute of Scientific and Technical Information of China (English)

    杨秀颖; 强桂芬; 张莉; 杜冠华

    2011-01-01

    Aim To investigate the protective effect of Salvianolic acid A (SalA) on myocardial ischemiareperfusion injury and the related mechanisms. Methods Male Sprague Dawley rats were subjected to 10 min of ischemia induced by ligation of the left coronary artery and followed by 2h of reperfusion. 10 min before ischemia, SalA groups were given SalA( 1.5 mg ·kg-1, 0.5 mg · kg-1 respectively ) by intravenous injection, control group received Lidocaine (5 mg·kg-1 ). The effect of SalA on ischemia-reperfusion induced arrhythmia in vivo was observed. We further investigated the effect of SalA on cultured primary neonatal rats cardiac myocytes exposed to hypoxia-reoxygenation. Results Sal A( 1.5 mg · kg -1 ) decreased the ischemic-reperfusion induced arrhythmia and reduced the blood CK and CK-MB levels. SalA had a protective effect on the hypoxia-reoxygenation injury in cardiac myocytes. SalA increased the intracelluar ATP production, and decreased the KCl-induced intracelluar Ca2+ elevation and mitochondrial membrane potential. Conclusion SalA has a protective effect on the myocardial injury induced by ischemia-reperfusion,which might be attributed to the antioxidant activity,the inhibition of calcium paradox, protection of mitochondrial function, and enhancement of the cardiac myocytes' ATP content.%目的 研究丹酚酸A对缺血/再灌注性心肌的保护作用及机制探讨.方法 采用Sprague Dawley大鼠冠状动脉左前降支结扎10 min,再灌注2 h,评价丹酚酸A (1.5、0.5 mg·kg-1)静脉给药对在体状态下大鼠心律失常的影响.以利多卡因(5 mg·kg-1)为阳性对照,各给药组均为结扎前10 min给药.同时评价丹酚酸A对培养的心肌细胞缺氧-复氧损伤的影响.结果 丹酚酸A 1.5 mg·kg-1剂量组静脉给药可降低由于心肌缺血/再灌注引起的心律失常发生率,减少肌酸激酶和肌酸激酶同工酶MB从胞体中的漏出.另外,丹酚酸A可防止心肌细胞缺氧-复氧损伤,

  2. Effect of dispelling toxins and dredging collaterals meridians and collaterals on myocardial enzyme in rabbit with myocardial ischemia/reperfusion injury%解毒通络方对兔心肌缺血再灌注损伤心肌酶的影响

    Institute of Scientific and Technical Information of China (English)

    杨健

    2012-01-01

    Objective To investigate the effects of dispelling toxins and dredging collaterals meridians and collaterals on myocardial enzyme in rabbit with myocardial ischemia/reperfusion injury. Methods 32 Japanese white rabbits were randomly divided into four groups,sham operation group,myocardial ischemia group,dispelling toxins and dredging collaterals therapy low dosage group ( group C) , dispelling toxins and dredging collaterals therapy high dosage group (group D). There were 8 rabbits in each group. Low dose group and the high dose group were 3. 16,6. 32 g/( kg · d) of crude drug. Liquid volume of 15 mL was administered orally. The equal volume of 0.9% sodium chloride injection was administered orally in the blank control group and model group for 5 days of continuous administration. The threading,ligation of left anterior descending branch was carried out in dredging collaterals group B, C and D. Open ligation achieved reperfusion after 30 min, the blank control group only wear line was not ligated. The levels of AST.LDH, CK and CK - MB were measured in each group. Results The levels of AST、LDH、CK、CK — MB in group B,C and D were significantly increased in comparison with those in group A (P 0. 05 ). Conclusion Dispelling toxins and dredging collaterals therapy may .reduce injury in myocardial cell,it has protective effect on myocardial ischemia/reperfusion.%目的 研究解毒通络方对实验性兔心肌缺血再灌注损伤( MIRI)血清心肌酶的影响.方法 将32只日本大耳白兔随机分为4组,即空白对照组、模型组、解毒通络方低剂量组及解毒通络方高剂量组,每组各8只.解毒通络方低、高剂量组分别予3.16、6.32 g/(kg·d)生药,溶液量15 mL灌胃给药;空白对照组和模型组分别予等容积0.9%氯化钠注射液灌胃给药.均连续5d.然后模型组、解毒通络方低剂量组及解毒通络方高剂量组行左冠状动脉前降支穿线,结扎,30 min后打开结扎实现再灌注,空白

  3. Cardioprotective Effects of Total Flavonoids Extracted from Xinjiang Sprig Rosa rugosa against Acute Ischemia/Reperfusion-Induced Myocardial Injury in Isolated Rat Heart.

    Science.gov (United States)

    Hou, Xuejiao; Han, Jichun; Yuan, Changsheng; Ren, Huanhuan; Zhang, Ya; Zhang, Tao; Xu, Lixia; Zheng, Qiusheng; Chen, Wen

    2016-01-01

    This study evaluated the antioxidative and cardioprotective effects of total flavonoids extracted from Xinjiang sprig Rosa rugosa on ischemia/reperfusion (I/R) injury using an isolated Langendorff rat heart model. The possible mechanism of Xinjiang sprig rose total flavonoid (XSRTF) against I/R injury was also studied. XSRTF (5, 10, and 20 µg/mL) dissolved in Krebs-Henseleit buffer was administered to isolated rat heart. The XSRTF showed remarkable scavenging effects against 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, and superoxide anion radicals in vitro. XSRTF pretreatment improved the heart rate, increased LVDP, and decreased CK and LDH levels in coronary flow. This pretreatment also increased SOD activity and GSH/GSSG ratio but decreased MDA, TNF-α, and CRP levels and IL-8 and IL-6 activities. The infarct size and cell apoptosis in the hearts from the XSRTF-treated group were lower than those in the hearts from the I/R group. Therefore, the cardioprotective effects of XSRTF may be attributed to its antioxidant, antiapoptotic, and anti-inflammatory activities.

  4. 牡荆素对大鼠在体心肌缺血再灌注损伤的保护作用和部分机制%Protective effects of vitexin on vivo myocardial ischemia reperfusion injury in rats and part of the mechanism

    Institute of Scientific and Technical Information of China (English)

    王斌; 王方

    2015-01-01

    Objective To investigate the protective effect of vitexin on vivo myocardial ischemia reperfusion injury in rats, and the part of its mechanism of action.Methods The vivo myocardial ischemia-reperfusion injury in rats were es-tablished, which were divided into model group, sham operation group, puerarin group and vitexin group, myocardial infarct size and serum markers of rat model were measured, and the results were analyzed and compared.Results Myocardial in-farct size was reduced to varying degrees in drug groups, in which the largest decline of IS/AAR was the vitexin 1.5 mg/kg group, the inhibition rate was 28.71%.Conclusions Vitexin can effectively reduce the myocardial infarct size of vivo myo-cardial ischemia-reperfusion injury in rats, and exerts its protective effect by enhancing the body’s antioxidant effect.%目的:探讨牡荆素对大鼠在体心肌缺血再灌注损伤的保护作用,并对其部分作用机制。方法建立大鼠在体心肌缺血再灌注损伤动物模型,将其分为模型组、假手术组、葛根素组和牡荆素组,对各组大鼠模型的心肌梗死面积和相关血清标志物进行测定,并对结果进行分析对比。结果药物组大鼠心肌梗死面积均存在不同程度的降低,其中以牡荆素1.5 mg/kg组大鼠IS/AAR下降幅度最大,抑制率为28.71%。结论牡荆素能够有效降低大鼠在体心肌缺血再灌注损伤模型的心肌梗死面积,通过增强机体的抗氧化作用发挥其保护作用。

  5. Influence of Tiaozhi Tongluo Capsules on Inflammatory Response after Myocardial Ischemia Reperfusion Injury%调脂通络胶囊对心肌IRI大鼠炎症反应的影响

    Institute of Scientific and Technical Information of China (English)

    王永霞; 王彩歌; 任琳琳; 吴先杰; 王幼平; 朱明军

    2013-01-01

    Objective: By measuring the level of myeloperoxidase ( MPO) , infarction weight ratio, myocardial cell morphology, to observe the myocardial protective effects and possible mechanism of Tiaozhi Tongluo capsules for myocardial ischemia-reperfusion injury (MIRI). Method: Ninety-six male Wistar rats were fed with high fat diet for 4 weeks except the non-fat model group. The rats were randomized into six groups and drug intervention or saline for 4 weeks; (1 ) fat model group; (2) non-fat model group; (3) statin group; (4) Tiaozhi Tongluo capsules 8.64 g ·kg-1·d-1; (5) Tiaozhi Tongluo capsules 4. 32 g ·kg-1·d-1; (6) Tiaozhi Tongluo capsules 2. 16 g ·kg-1·d-1 . The same volume of saline was infused in fat model and non-fat model group. After 2 hours of the last intragastric infusion, the chest was opened and the left anterior desending coronary arteries (LAD) was ligated for 30 min and undamped for 24 hours for all the rats. After 24 h of reperfusion, the level of blood lipids, cardiac enzymes in serum or the content of MPO in ischemic myocardium tissue ( half of the animals of each group) were measured. Myocardial tissue near the apical about 0. 5 cm2 was taken for HE staining, morphological changes were observed. The myocardial tissue of the rest animals in each group was stained by Evans blue and TTC. Then these slices were immersed in 4% paraformaldehyde formalin, ischemic zone size (IZS) , infarct size (IS) , the ischemic weight ratio and the infarction weight ratio were determined. Result: The level of cardial enzymes, MPO and infarction weight ratio were significantly higher in fat model group compared to the non-fat model group (P < 0. 01 ) . The drug treatment groups could significantly reduce the level of cardial enzymes, MPO and infarction weight ratio compared to fat model group (P < 0. 01). Conclusion: Tiaozhi Tongluo capsules and atorvastatin could protect myocardial cells by reducing the infiltration of inflammatory cells, which might be related to

  6. 山奈酚预处理对大鼠心脏缺血再灌注损伤的影响%Effects of Kaempferol Against Myocardial Ischemia-Reperfusion Injury in Rat Heart

    Institute of Scientific and Technical Information of China (English)

    周明杰; 刘立群

    2015-01-01

    目的:观察山奈酚预处理对大鼠心肌缺血再灌注损伤的影响。方法应用Langendorff灌流装置构建大鼠心脏缺血再灌注模型,120只雄性Sprague-Dawley(SD)大鼠随机分为3组,对照组(n=40),单纯缺血再灌注组( n=40)和山奈酚处理组( n=40)。心功能指标从Langendorff灌流装置上获取;采用ELISA法检测CK-MB( Creatine Kinase Isoenzyme)及SOD( superoxide dismutase)含量;采用TUNEL法检测心肌细胞凋亡。结果山奈酚预处理能显著提高大鼠心脏缺血再灌注后心功能的恢复及心肌组织内SOD的含量,同时显著降低灌流液中CK-MB的含量,减少再灌注后心肌细胞凋亡。结论山奈酚预处理对缺血再灌注后大鼠心脏具有明显的保护作用。%Objective To evaluate the effect of kaempferol against myocardial ischemia-reperfusion injury in rats.Methods Application of Langendorff simulated the model of ischemia-reperfusion.One hundred and twenty male SD rats were randomly divided into 3 groups,group A was the control group(n=40);group B was the ischemia-reperfu-sion group(n=40);group C was the kaempferol-treated group(n=40).Myocardial function were recorded at the screen of Langendorff.The levels of CK-MB and SOD were determined by enzyme linked immunosorbent assay( ELISA) ,Cardio-myocyte apoptosis was determined using terminal deoxynucleotidyl nick-end labeling(TUNEL).Results Pretreatment with kaempferol significantly improved the recovery of heart function as well as increased the levels of SOD.However, pretreatment with kaempferol reduced TUNEL-positive cell rate as well as decreased the levels of CK-MB.Conclusion Pretreatment with kaempferol provides cardioprotection in rats with I/R.

  7. 术后镇痛对冠心病患者围术期心肌损伤的影响%Effects of Postoperative Different Analgesia Styles on Perioperative Myocardial Injury in Coronary Heart Disease Patients Undergoing Thoracic Surgery

    Institute of Scientific and Technical Information of China (English)

    严丽萍; 吴明慧; 陈丽; 王莹

    2011-01-01

    Objective To compare the effects of postoperative different analgesia on the myocardial injury in coronary heart disease patients undergoing thoracic surgery, and to offer a theoretical foundation for better analgesia. Methods Fouty patients, ASA Ⅱ - Ⅲ ,undergoing thoracic surgery under general anesthesia combined with epidural block were randomly allocated to patientcontrolled intravenous analgesia(PCIA) group( n = 20) and patient-controlled epidural analgesia( PCEA ) group( n = 20 ). Blood samples were prepared for the measurement of cTnI. The ST segment changes were recorded. The analgesia effect was assessed using visual analog scores(VAS). Results The values of cTnI in PECA group were significant lower than those in group PICA ( P <0.05 ). The total leads of depression of ST segment (NST) and sum of depression of ST segment( Σ ST) in PECA group were fewer than those in group PICA at different time points (P < O. 05). Conclusion Compared with group PICA, PECA gets a better analgesia and may significantly protect the myocardial.%目的 比较不同镇痛方法对胸科冠心病患者围术期心肌损伤的影响,为胸科冠心病患者选择适宜的术后镇痛方式.方法 择期行胸科手术的冠心病患者40例,ASAⅡ~Ⅲ级,随机分为静脉自控镇痛组(HCA组),硬膜外自控镇痛组(PECA组),每组20例.两组患者均在全麻复合硬膜外阻滞下手术,术毕分别接PICA和PECA.观察两组患者在围术期血清肌钙蛋白Ⅰ(cTnI)浓度及心电图ST段变化,用视觉模拟评估法评估镇痛效果(VSA评分).结果 两组患者术毕血浆cTnI浓度PECA组比PICA组的浓度明显降低(P<0.05).术后各时点心电图ST段改变导联数(NST)和ST段压低幅度的总和(∑ST)PECA组明显比PICA组减少(P<0.05).结论 胸科冠心病患者术后使用PECA镇痛对防治心肌受损有一定的保护作用.

  8. Exergetic sustainability evaluation of irreversible Carnot refrigerator

    Science.gov (United States)

    Açıkkalp, Emin

    2015-10-01

    Purpose of this paper is to assess irreversible refrigeration cycle by using exergetic sustainability index. In literature, there is no application of exergetic sustainability index for the refrigerators and, indeed, this index has not been derived for refrigerators. In this study, exergetic sustainability indicator is presented for the refrigeration cycle and its relationships with other thermodynamics parameters including COP, exergy efficiency, cooling load, exergy destruction, ecological function and work input are investigated. Calculations are conducted for endoreversible and reversible cycles and then results obtained from the ecological function are compared. It is found that exergy efficiency, exergetic sustainable index reduce 47.595% and 59.689% and rising at the COP is 99.888% is obtained for endoreversible cycle. Similarly, exergy efficiency and exergetic sustainability index reduce 90.163% and 93.711% and rising of the COP is equal to 99.362%.

  9. Irreversibility, Information and Randomness in Quantum Measurements

    CERN Document Server

    Mayburov, S N

    2012-01-01

    Irreversibility in quantum measurements is considered from the point of quantum information theory. For that purpose the information transfer between the measured object S and measuring system O is analyzed. It's found that due to the principal constraints of quantum-mechanical origin, the information about the purity of S state isn't transferred to O during the measurement of arbitraryS observable V. Consequently O can't discriminate the pure and mixed S ensembles with the same . As the result, the random outcomes should be detected by O in V measurement for S pure ensemble of V eigenstate superposition. It's shown that the outcome probabilties obey to Born rule. The influence of O decoherence by its environment is studied, however the account of its effects doesn't change these results principally.

  10. Power Fluctuations and Irreversibility in Turbulence

    CERN Document Server

    Xu, Haitao; Falkovich, Gregory; Bodenschatz, Eberhard; Shats, Michael; Xia, Hua; Francois, Nicolas; Boffetta, Guido

    2013-01-01

    The breaking of detailed balance, the symmetry between forward and backward probability transition between two states, is crucial to understand irreversible systems. In hydrodynamic turbulence, a far-from equilibrium system, we observe a strong manifestation of the breaking of detailed balance by following the evolution of the kinetic energy of individual fluid elements. We found in all the flows that we have investigated that fluid elements decelerate faster than they accelerate, giving rise to negative third moment of energy increments, independently of space dimensionality. The exchange of energy between fluid elements however is fundamentally different in two and three dimensions. Pressure forces redistribute energy from fast to slow elements in two dimensions; but from slow to fast ones in three dimensions, possibly implying a runaway of energy.

  11. Work Criteria Function of Irreversible Heat Engines

    Directory of Open Access Journals (Sweden)

    Mahmoud Huleihil

    2014-01-01

    Full Text Available The irreversible heat engine is reconsidered with a general heat transfer law. Three criteria known in the literature—power, power density, and efficient power—are redefined in terms of the work criteria function (WCF, a concept introduced in this study. The formulation enabled the suggestion and analysis of a unique criterion—the efficient power density (which accounts for the efficiency and power density. Practically speaking, the efficient power and the efficient power density could be defined on any order based on the WCF. The applicability of the WCF is illustrated for the Newtonian heat transfer law (n=1 and for the radiative law (n=4. The importance of WCF is twofold: it gives an explicit design and educational tool to analyze and to display graphically the different criteria side by side and thus helps in design process. Finally, the criteria were compared and some conclusions were drawn.

  12. Diffusion of irreversible energy technologies under uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Cacallo, J.D.; Sutherland, R.J.

    1993-09-01

    This paper presents a model of technology diffusion is consistent with characteristics of participants in most energy markets. Whereas the models used most widely for empirical research are based on the assumption that the extended delays in adoption of cost-saving innovations are the result of either lack of knowledge about the new processes or heterogeneity across potential adopters, the model presented in this paper is based on the strategic behavior by firms. The strategic interdependence of the firms` decisions is rooted in spillover effects associated with an inability to exclude others from the learning-by-doing acquired when a firm implements a new technology. The model makes extensive use of recent developments in investment theory as it relates irreversible investments under uncertainty.

  13. Metrics and Energy Landscapes in Irreversible Thermodynamics

    Directory of Open Access Journals (Sweden)

    Bjarne Andresen

    2015-09-01

    Full Text Available We describe how several metrics are possible in thermodynamic state space but that only one, Weinhold’s, has achieved widespread use. Lengths calculated based on this metric have been used to bound dissipation in finite-time (irreversible processes be they continuous or discrete, and described in the energy picture or the entropy picture. Examples are provided from thermodynamics of heat conversion processes as well as chemical reactions. Even losses in economics can be bounded using a thermodynamic type metric. An essential foundation for the metric is a complete equation of state including all extensive variables of the system; examples are given. Finally, the second law of thermodynamics imposes convexity on any equation of state, be it analytical or empirical.

  14. Chemical kinetics, stochastic processes, and irreversible thermodynamics

    CERN Document Server

    Santillán, Moisés

    2014-01-01

    This book brings theories in nonlinear dynamics, stochastic processes, irreversible thermodynamics, physical chemistry, and biochemistry together in an introductory but formal and comprehensive manner.  Coupled with examples, the theories are developed stepwise, starting with the simplest concepts and building upon them into a more general framework.  Furthermore, each new mathematical derivation is immediately applied to one or more biological systems.  The last chapters focus on applying mathematical and physical techniques to study systems such as: gene regulatory networks and ion channels. The target audience of this book are mainly final year undergraduate and graduate students with a solid mathematical background (physicists, mathematicians, and engineers), as well as with basic notions of biochemistry and cellular biology.  This book can also be useful to students with a biological background who are interested in mathematical modeling, and have a working knowledge of calculus, differential equatio...

  15. Irreversible electroporation: state of the art.

    Science.gov (United States)

    Wagstaff, Peter Gk; Buijs, Mara; van den Bos, Willemien; de Bruin, Daniel M; Zondervan, Patricia J; de la Rosette, Jean Jmch; Laguna Pes, M Pilar

    2016-01-01

    The field of focal ablative therapy for the treatment of cancer is characterized by abundance of thermal ablative techniques that provide a minimally invasive treatment option in selected tumors. However, the unselective destruction inflicted by thermal ablation modalities can result in damage to vital structures in the vicinity of the tumor. Furthermore, the efficacy of thermal ablation intensity can be impaired due to ther