P4618Lack of CD31 results in microvascular plugging and increased infarction size in an experimental model of myocardial ischemia-reperfusion injury

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
V Syvannarath ◽  
S Di Carlo ◽  
G Even ◽  
B Gachet ◽  
A Nicoletti ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Tyrosine Phosphatase ◽  
Constitutive Expression ◽  
Blue Dye ◽  
Macrophage Phenotype ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride ◽  
The Impact

Abstract Background The success of coronary recanalization therapy for the treatment of myocardial infarction can be hampered by microvascular plugging which prevents effective reperfusion of the ischemic tissue. Due to its constitutive expression in platelets, leukocytes, and endothelial cells and its peculiar tyrosine phosphatase cell detaching signaling properties, the trans-homophilic CD31 receptor may be important to modulate platelet and leukocyte aggregation in the microvasculature. Objective To investigate the impact of CD31 genetic deficiency on the infarct size, peri-infarction microvascular plugging and macrophage phenotype in a mouse model of heart ischemia/reperfusion. Methods Cardiac ischemia was induced in WT and CD31 KO mice (n=30, 15 females and 15 males in each group) by surgical ligation of the left anterior descending coronary artery (LAD) for 45 minutes followed by reperfusion for 72 hours. The area at risk (AAR) and necrotic zone (NZ) were assessed using ImageJ software on three consecutive 1 mm thick slices of the left ventricle (LV) by a combination of a blue dye and 2,3,5-triphenyltetrazolium chloride staining. Parallel sets of experiments served to evaluate by both fluorescence microscopy and cytometry the presence of microvascular plugs and leukocyte phenotype in the infarction area as compared to the peri-necrotic myocardium. Results The AAR was similar in WT and CD31 KO mice (41,7±3,5 vs 37±2,9% of LV, NS) whereas the size of myocardial infarction was significantly greater in CD31 KO as compared to WT mice (23,4±2 vs 17,8±1,7% of LV, p<0,05). Immunofluorescent microscopy showed a dramatic increase in microvascular platelets-rich plugs around the infarction in CD31 KO mice (Figure), confirmed by cytometry analysis (9749±573 vs 5976±376 platelet-leukocyte aggregates/mg of tissue, p<0.001). Furthermore, we found that the ratio between M1 and M2 type macrophages in the peri-infarction myocardium was significantly increased in CD31 KO mice (0,7±0.07) as compared to WT mice (0,4±0.06, p<0,01). Conclusions Our data suggest that CD31 is important for reducing the size of necrosis following coronary recanalization procedures by preventing the no-reflow phenomenon due to microvascular plugging and by promoting a reparative phenotype of peri-infarction macrophages. Acknowledgement/Funding Institut Servier - ANRT (CIFRE doctoral grant)

scholarly journals Cardioprotective Effect of Novel Matrix Metalloproteinase Inhibitors

2020 ◽  
Vol 21 (19) ◽  
pp. 6990
Author(s):  
Kamilla Gömöri ◽  
Tamara Szabados ◽  
Éva Kenyeres ◽  
Judit Pipis ◽  
Imre Földesi ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Infarct Size ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Positive Control ◽  
Matrix Metalloproteinase 2 ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride

Background: We recently developed novel matrix metalloproteinase-2 (MMP-2) inhibitor small molecules for cardioprotection against ischemia/reperfusion injury and validated their efficacy in ischemia/reperfusion injury in cardiac myocytes. The aim of the present study was to test our lead compounds for cardioprotection in vivo in a rat model of acute myocardial infarction (AMI) in the presence or absence of hypercholesterolemia, one of the major comorbidities affecting cardioprotection. Methods: Normocholesterolemic adult male Wistar rats were subjected to 30 min of coronary occlusion followed by 120 min of reperfusion to induce AMI. MMP inhibitors (MMPI)-1154 and -1260 at 0.3, 1, and 3 µmol/kg, MMPI-1248 at 1, 3, and 10 µmol/kg were administered at the 25th min of ischemia intravenously. In separate groups, hypercholesterolemia was induced by a 12-week diet (2% cholesterol, 0.25% cholic acid), then the rats were subjected to the same AMI protocol and single doses of the MMPIs that showed the most efficacy in normocholesterolemic animals were tested in the hypercholesterolemic animals. Infarct size/area at risk was assessed at the end of reperfusion in all groups by standard Evans blue and 2,3,5-triphenyltetrazolium chloride (TTC) staining, and myocardial microvascular obstruction (MVO) was determined by thioflavine-S staining. Results: MMPI-1154 at 1 µmol/kg, MMPI-1260 at 3 µmol/kg and ischemic preconditioning (IPC) as the positive control reduced infarct size significantly; however, this effect was not seen in hypercholesterolemic animals. MVO in hypercholesterolemic animals decreased by IPC only. Conclusions: This is the first demonstration that MMPI-1154 and MMPI-1260 showed a dose-dependent infarct size reduction in an in vivo rat AMI model; however, single doses that showed the most efficacy in normocholesterolemic animals were abolished by hypercholesterolemia. The further development of these promising cardioprotective MMPIs should be continued with different dose ranges in the study of hypercholesterolemia and other comorbidities.

scholarly journals Acute myocardial infarction in mice: assessment of transmurality by strain rate imaging

2007 ◽  
Vol 293 (1) ◽  
pp. H496-H502 ◽  
Author(s):  
Hélène Thibault ◽  
Ludovic Gomez ◽  
Erwan Donal ◽  
Gerard Pontier ◽  
Marielle Scherrer-Crosbie ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Strain Rate ◽  
Murine Model ◽  
Left Ventricular ◽  
Lv Function ◽  
Blue Dye ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride ◽  
In Vivo Evaluation ◽  
Strain Rate Imaging

In vivo evaluation of the transmural extension of myocardial infarction (TEI) is crucial to prediction of viability and prognosis. With the rise of transgenic technology, murine myocardial infarction (MI) models are increasingly used. Our study aimed to evaluate systolic strain rate (SR), a new parameter of regional function, to quantify TEI in a murine model of acute MI induced by various durations of ischemia followed by 24 h of reperfusion. Global and regional left ventricular (LV) function were assessed by echocardiography (13 MHz, Vivid 7, GE) in 4 groups of wild-type mice (C57BL/6, 2 mo old): a sham-treated group ( n = 10) and three MI groups [30 ( n = 11), 60 ( n = 10), and 90 ( n = 9) min of left coronary artery occlusion]. Conventional LV dimensions, anterior wall (AW) thickening, and peak systolic SR were measured before and 24 h after reperfusion. Area at risk (AR) was measured by blue dye and infarct size (area of necrosis, AN) and TEI by triphenyltetrazolium chloride staining. AN increased with ischemia duration (25 ± 2%, 56 ± 5%, 71 ± 6% of AR for 30, 60, and 90 min, respectively; P < 0.05). LV end-diastolic volume significantly increased with ischemia duration (30 ± 5, 34 ± 5, 43 ± 5 μl; P < 0.05), whereas LV ejection fraction decreased (63 ± 5%, 58 ± 6%, 46 ± 5%; P < 0.05). AW thickening decrease was not influenced by ischemia duration. Conversely, systolic SR decreased with ischemia duration (13 ± 5, 4 ± 3, −2 ± 6 s−1; P < 0.05) and was significantly correlated with TEI ( r = 0.89, P < 0.01). Receiver operating characteristic (ROC) curves identified systolic SR as the most accurate parameter to predict TEI. In conclusion, in a murine model of MI, SR imaging is superior to conventional echocardiography to predict TEI early after MI.

Effect of crowding stress on tolerance to ischemia–reperfusion injury in young male and female hypertensive rats: molecular mechanisms

2015 ◽  
Vol 93 (9) ◽  
pp. 793-802 ◽  
Author(s):  
Veronika Ledvényiová-Farkašová ◽  
Iveta Bernátová ◽  
Peter Balis ◽  
Angelika Puzserova ◽  
Monika Barteková ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Social Stress ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Male And Female ◽  
Wky Rats ◽  
Crowding Stress ◽  
Wistar Kyoto ◽  
The Impact

Sex and social stress may represent risk factors in the etiology of hypertension and heart response to ischemia–reperfusion (I/R) injury. Phosphatidylinositol 3-kinase/protein kinase B (Akt) plays an important role in the processes associated with hypertension and myocardial tolerance to I/R, and may be involved in myocardial stress reaction. The impact of chronic stress on the response to I/R was investigated in the hearts of 7-week-old spontaneously hypertensive (SHR) and Wistar–Kyoto (WKY) rats of both sexes. Stress was induced by reducing living space to 70 cm2/100 g body mass of rat for 2 weeks, while the controls were kept at 200 cm2/100 g. Langendorff-perfused hearts, subjected to I/R, exhibited higher vulnerability to ventricular tachycardia in crowd-stressed SHR vs. the control rats, and this was more pronounced in the males. Myocardial infarction was not affected by crowding stress in any of the groups. Male and female SHR showed increased activation of cardiac Akt, whereas nitric oxide synthase activity (NOS) with pro-apoptotic signaling decreased in the males but was not altered in the females (vs. WKY rats). NOS was enhanced in the female SHR and WKY groups by comparison with the respective males. Stress only reduced NOS activity in the SHR groups, and without changes in apoptotic markers. In conclusion, we showed that stress in young SHR mainly affects the nonlethal markers for I/R, and has no impact on myocardial infarction and apoptosis, despite reduced NOS activity.

Positive end-expiratory pressure potentiates the severity of canine right ventricular ischemia-reperfusion injury

1992 ◽  
Vol 262 (1) ◽  
pp. H168-H176 ◽  
Author(s):  
W. E. Johnston ◽  
J. Vinten-Johansen ◽  
H. E. Shugart ◽  
W. P. Santamore
Keyword(s):  
At Risk ◽  
Blood Flow ◽  
Right Ventricular ◽  
Ischemia Reperfusion Injury ◽  
Gentian Violet ◽  
Ischemia Reperfusion ◽  
Rate Pressure Product ◽  
Positive End Expiratory Pressure ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride

Positive end-expiratory pressure (PEEP) increases right ventricular (RV) afterload and oxygen demands. However, whether increased RV oxygen demands with high levels of PEEP can potentiate the severity of RV ischemic damage is unknown. In 20 anesthetized, closed-chest dogs randomly assigned to 0 cmH2O PEEP (ZEEP; n = 10) or 15 cmH2O PEEP (PEEP; n = 10), RV blood flow (radioactive microspheres) and segmental shortening (ultrasonic crystals) were determined during 90 min ischemia and 120 min reperfusion while mean aortic pressure was maintained above 90 mmHg. The in vivo RV area at risk (gentian violet) and area of necrosis (triphenyltetrazolium chloride) were assessed. After application of 15 cmH2O PEEP, pulmonary vascular resistance increased by 75% (P less than 0.05). During ischemia, the RV rate-pressure product remained greater with PEEP (2,403 +/- 174 mmHg.beat.min-1) than with ZEEP (1,909 +/- 94 mmHg.beat.min-1; P less than 0.05), indicating higher oxygen demands with PEEP. The area at risk from ischemia relative to RV free wall tended to be greater with PEEP (68.5 +/- 2.4%) than with ZEEP (60.0 +/- 3.9%; P = 0.08), and collateral blood flow in this risk zone was significantly lower during ischemia with PEEP (9.0 +/- 1.7 ml.min-1 x 100 g-1) than with ZEEP (18.3 +/- 3.6 ml.min-1 x 100 g-1; P less than 0.05). Accordingly, PEEP extended RV necrosis in the area at risk from 21.8 +/- 5.3% (ZEEP) to 58.1 +/- 8.4% (PEEP; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Inhibiting YAP in Endothelial Cells From Entering the Nucleus Attenuates Blood-Brain Barrier Damage During Ischemia-Reperfusion Injury

2021 ◽  
Vol 12 ◽  
Author(s):  
Shuaishuai Gong ◽  
Huifen Ma ◽  
Fan Zheng ◽  
Juan Huang ◽  
Yuanyuan Zhang ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Ischemic Stroke ◽  
Blood Brain Barrier ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Brain Barrier ◽  
Critical Event ◽  
Blue Dye ◽  
Triphenyltetrazolium Chloride ◽  
Blood Brain

Blood-brain barrier (BBB) damage is a critical event in ischemic stroke, contributing to aggravated brain damage. Endothelial cell form a major component of the BBB, but its regulation in stroke has yet to be clarified. We investigated the function of Yes-associated protein 1 (YAP) in the endothelium on BBB breakdown during cerebral ischemia/reperfusion (I/R) injury. The effects of YAP on BBB dysfunction were explored in middle cerebral artery occlusion/reperfusion (MCAO/R)-injury model mice and using brain microvascular endothelial cells (BMEC) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) injury. The degree of brain injury was estimated using staining (2,3,5-Triphenyltetrazolium chloride, hematoxylin and eosin) and the detection of cerebral blood flow. BBB breakdown was investigated by examining the leakage of Evans Blue dye and evaluating the expression of tight junction (TJ)-associated proteins and matrix metallopeptidase (MMP) 2 and 9. YAP expression was up-regulated in the nucleus of BMEC after cerebral I/R injury. Verteporfin (YAP inhibitor) down-regulated YAP expression in the nucleus and improved BBB hyperpermeability and TJ integrity disruption stimulated by cerebral I/R. YAP-targeted small interfering RNA (siRNA) exerted the same effects in BMEC cells exposed to OGD/R injury. Our findings provide new insights into the contributions made by YAP to the maintenance of BBB integrity and highlight the potential for YAP to serve as a therapeutic target to modulate BBB integrity following ischemic stroke and related cerebrovascular diseases.

scholarly journals Role of ischemic preconditioning in cardioprotective mechanisms of mCRP deposited myocardium in a rat model

2020 ◽  
Author(s):  
Eun Na Kim ◽  
Jae-Sung Choi ◽  
Chong Jai Kim ◽  
So Ra Kim ◽  
Ki-Bong Kim ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Mrna Expression ◽  
Ischemic Preconditioning ◽  
Rat Model ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Myocardial Damage ◽  
Study Groups ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride

AbstractThe deposition of monomeric C-reactive protein (mCRP) in the myocardium aggravates ischemia-reperfusion injury (IRI) and myocardial infarction. Ischemic preconditioning (IPC) is known to protect the myocardium against IRI. We evaluated the effects of IPC on mCRP-deposited myocardium due to IRI in a rat model. Myocardial IRI was produced by ligation of the coronary artery. Direct IPC was applied before IRI using multiple short direct occlusions of the coronary artery. CRP was infused intravenously after IRI. The study groups included the following: sham (n=3), IRI only (n=5), IRI+CRP (n=9), and IPC+IRI+CRP (n=6) groups. The infarct area and area at risk were assessed using Evans blue and 2,3,5-triphenyltetrazolium chloride (2,3,5-TTC) staining. Additionally, mCRP immunostaining and interleukin (IL)-6 mRNA reverse transcriptase-polymerase chain reaction (RT-PCR) were performed. In the IRI+CRP group, the infarcted area, mCRP deposition, and IL-6 mRNA expression were higher than those in the IRI only group. However, in the IPC+IRI+CRP group, the infarction (20% vs. 34% p=0.085) and mCRP myocardial deposition (21% vs. 44%, p=0.026) were lower and IL-6 mRNA expression was higher than those in the IRI+CRP group (fold change, 407 vs. 326, p=0.808), although this was not statistically significant. IPC has cardioprotective effects against myocardial damage caused by mCRP deposition. This protective effect is related to the increase in IL-6 mRNA expression.

Increased mitochondrial calcium coexists with decreased reperfusion injury in postconditioned (but not preconditioned) hearts

2008 ◽  
Vol 294 (1) ◽  
pp. H386-H391 ◽  
Author(s):  
Laurent Argaud ◽  
Odile Gateau-Roesch ◽  
Lionel Augeul ◽  
Elisabeth Couture-Lepetit ◽  
Joseph Loufouat ◽  
...  
Keyword(s):  
Infarct Size ◽  
Reperfusion Injury ◽  
Mitochondrial Permeability Transition ◽  
Ischemia Reperfusion ◽  
Control Group ◽  
Blue Dye ◽  
Mitochondrial Calcium ◽  
Area At Risk ◽  
Triphenyltetrazolium Chloride ◽  
Pore Opening

Ca2+ is the main trigger for mitochondrial permeability transition pore opening, which plays a key role in cardiomyocyte death after ischemia-reperfusion. We investigated whether a reduced accumulation of mitochondrial Ca2+ might explain the attenuation of lethal reperfusion injury by postconditioning. Anesthetized New Zealand White rabbits underwent 30 min of ischemia, followed by either 240 (infarct size protocol) or 60 (mitochondria protocol) min of reperfusion. They received either no intervention (control), preconditioning by 5-min ischemia and 5-min reperfusion, postconditioning by four cycles of 1-min reperfusion and 1-min ischemia at the onset of reflow, or pharmacological inhibition of the transition pore opening by N-methyl-4-isoleucine-cyclosporin (NIM811; 5 mg/kg iv) given at reperfusion. Area at risk and infarct size were assessed by blue dye injection and triphenyltetrazolium chloride staining. Mitochondria were isolated from the risk region for measurement of 1) Ca2+ retention capacity (CRC), and 2) mitochondrial content of total (atomic absorption spectrometry) and ionized (potentiometric technique) calcium concentration. CRC averaged 0.73 ± 0.16 in control vs. 4.23 ± 0.17 μg Ca2+/mg proteins in shams ( P < 0.05). Postconditioning, preconditioning, or NIM811 significantly increased CRC ( P < 0.05 vs. control). In the control group, total and free mitochondrial calcium significantly increased to 2.39 ± 0.43 and 0.61 ± 0.10, respectively, vs. 1.42 ± 0.09 and 0.16 ± 0.01 μg Ca2+/mg in sham ( P < 0.05). Surprisingly, whereas total and ionized mitochondrial Ca2+ decreased in preconditioning, it significantly increased in postconditioning and NIM811 groups. These data suggest that retention of calcium within mitochondria may explain the decreased reperfusion injury in postconditioned (but not preconditioned) hearts.

scholarly journals Circular RNA TTC3 regulates cerebral ischemia-reperfusion injury and neural stem cells by miR-372-3p/TLR4 axis in cerebral infarction

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bo Yang ◽  
Li’e Zang ◽  
Jingwen Cui ◽  
Linlin Wei
Keyword(s):  
Stem Cells ◽  
Cerebral Ischemia ◽  
Cerebral Infarction ◽  
Neural Stem Cells ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Cerebral Ischemia Reperfusion ◽  
The Impact

Abstract Background Stroke serves as a prevalent cerebrovascular disorder with severe cerebral ischemia/reperfusion (CIR) injury, in which neural stem cells (NSCs) play critical roles in the recovery of cerebral function. Circular RNAs (circRNAs) have been widely found to participate in stroke and NSC modulation. However, the role of circRNA TTC3 (circTTC3) in the regulation of CIR injury and NSCs remains elusive. Here, we aimed to explore the impact of circTTC3 on CIR injury and NSCs. Methods The middle cerebral artery occlusion/repression (MCAO/R) model was established in C57BL/6J mice. The primary astrocytes were isolated from the cerebellum from C57BL/6J mice. The primary NSCs were obtained from rat embryos. The effect of circTTC3 on CIR injury and NSCs was analyzed by TTC staining, qPCR, Western blot, LDH colorimetric kits, MTT assays, Annexin V-FITC Apoptosis Detection Kit, luciferase reporter gene assays, and others in the system. Results Significantly, the expression of circTTC3 was elevated in the MCAO/R mice and oxygen and glucose deprivation (OGD)-treated astrocytes. The depletion of circTTC3 attenuated cerebral infarction, neurological score, and brain water content. The OGD treatment induced apoptosis and the levels of lactate dehydrogenase (LDH) in the astrocytes, in which circTTC3 depletion reduced this phenotype in the system. Moreover, the depletion of circTTC3 promoted the proliferation and upregulated the nestin and β-tubulin III expression in NSCs. Mechanically, circTTC3 was able to sponge miR-372-3p, and miR-372-3p can target Toll-like receptor 4 (TLR4) in NSCs. The miR-372-3p inhibitor or TLR4 overexpression could reverse circTTC3 depletion-mediated astrocyte OGD injury and NSC regulation. Conclusion Thus, we conclude that circTTC3 regulates CIR injury and NSCs by the miR-372-3p/TLR4 axis in cerebral infarction. Our finding presents new insight into the mechanism by which circTTC3 modulates CIR injury and NSC dysfunction. CircTTC3, miR-372-3p, and TLR4 may serve as potential targets for the treatment of CIR injury during stroke.

scholarly journals Reducing Cardiac Injury during ST-Elevation Myocardial Infarction: A Reasoned Approach to a Multitarget Therapeutic Strategy

2021 ◽  
Vol 10 (13) ◽  
pp. 2968
Author(s):  
Alessandro Bellis ◽  
Giuseppe Di Gioia ◽  
Ciro Mauro ◽  
Costantino Mancusi ◽  
Emanuele Barbato ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Reperfusion Injury ◽  
Therapeutic Strategy ◽  
Ventricular Remodeling ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Left Ventricular ◽  
St Elevation Myocardial Infarction ◽  
Ischemic Time ◽  
St Elevation

The significant reduction in ‘ischemic time’ through capillary diffusion of primary percutaneous intervention (pPCI) has rendered myocardial-ischemia reperfusion injury (MIRI) prevention a major issue in order to improve the prognosis of ST elevation myocardial infarction (STEMI) patients. In fact, while the ischemic damage increases with the severity and the duration of blood flow reduction, reperfusion injury reaches its maximum with a moderate amount of ischemic injury. MIRI leads to the development of post-STEMI left ventricular remodeling (post-STEMI LVR), thereby increasing the risk of arrhythmias and heart failure. Single pharmacological and mechanical interventions have shown some benefits, but have not satisfactorily reduced mortality. Therefore, a multitarget therapeutic strategy is needed, but no univocal indications have come from the clinical trials performed so far. On the basis of the results of the consistent clinical studies analyzed in this review, we try to design a randomized clinical trial aimed at evaluating the effects of a reasoned multitarget therapeutic strategy on the prevention of post-STEMI LVR. In fact, we believe that the correct timing of pharmacological and mechanical intervention application, according to their specific ability to interfere with survival pathways, may significantly reduce the incidence of post-STEMI LVR and thus improve patient prognosis.

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