scholarly journals Novel Pharmaceutical Strategy for Selective Abrogation of TSP1-Induced Vascular Dysfunction by Decoy Recombinant CD47 Soluble Receptor in Prophylaxis and Treatment Models

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 642
Author(s):  
Molly Yao ◽  
Jalicia Sturdivant ◽  
Aren Ebrahimi ◽  
Samayita Ganguly ◽  
Tamer Elbayoumi
Keyword(s):  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Vascular Dysfunction ◽  
Ischemia Reperfusion ◽  
Dose Range ◽  
Control Level ◽  
Cardiovascular Complications ◽  
Receptor Protein ◽  
Dose Titration ◽  
Set Up

Elevated thrombospondin 1 (TSP1) is a prevalent factor, via cognate receptor CD47, in the pathogenesis of cardiovascular conditions, including ischemia-reperfusion injury (IRI) and pulmonary arterial hypertension (PAH). Moreover, TSP1/CD47 interaction has been found to be associated with platelet hyperaggregability and impaired nitric oxide response, exacerbating progression in IRI and PAH. Pathological TSP1 in circulation arises as a target of our novel therapeutic approach. Our “proof-of-concept” pharmacological strategy relies on recombinant human CD47 peptide (rh-CD47p) as a decoy receptor protein (DRP) to specifically bind TSP1 and neutralize TSP1-impaired vasorelaxation, strongly implicated in IRI and PAH. The binding of rh-CD47p and TSP1 was first verified as the primary mechanism via Western blotting and further quantified with modified ELISA, which also revealed a linear molar dose-dependent interaction. Ex vivo, pretreatment protocol with rh-CD47p (rh-CD47p added prior to TSP1 incubation) demonstrated a prophylactic effect against TSP1-impairment of endothelium-dependent vasodilation. Post-treatment set-up (TSP1 incubation prior to rh-CD47p addition), mimicking pre-existing excessive TSP1 in PAH, reversed TSP1-inhibited vasodilation back to control level. Dose titration identified an effective molar dose range (approx. ≥1:3 of tTSP1:rh-CD47p) for prevention of/recovery from TSP1-induced vascular dysfunction. Our results indicate the great potential for proposed novel decoy rh-CD47p-therapy to abrogate TSP1-associated cardiovascular complications, such as PAH.

scholarly journals Graft Preservation Solution DuraGraft® Alleviates Vascular Dysfunction Following In Vitro Ischemia/Reperfusion Injury in Rats

2021 ◽  
Vol 14 (10) ◽  
pp. 1028
Author(s):  
Sevil Korkmaz-Icöz ◽  
Belinda Ballikaya ◽  
Jasmin Soethoff ◽  
Patricia Kraft ◽  
Alex Ali Sayour ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Vascular Function ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Vascular Dysfunction ◽  
Ischemia Reperfusion ◽  
Artery Bypass ◽  
Organ Bath ◽  
High Potassium ◽  
Arterial Grafts

Vascular ischemia/reperfusion injury (IRI) in patients undergoing coronary artery bypass grafting can result in graft failure and the need for repeat revascularization procedures. DuraGraft® has been shown to protect structure and function in saphenous vein grafts against IRI. We compared the effect of DuraGraft® to saline solution on arterial grafts submitted to IRI. Rat thoracic aortic rings were harvested and immediately mounted in organ bath chambers (control, n = 7 rats) or underwent cold ischemic preservation either in saline (IR, n = 9 rats) or DuraGraft® (IR+Dura, n = 9 rats). Vascular function was measured ex vivo and immunohistochemistry was performed. Impaired maximum vasorelaxation (Rmax) to ACh in the IR-group compared to controls was ameliorated by DuraGraft®, indicating an improvement in endothelial function (Rmax to ACh (%): IR + Dura 73 ± 2 vs. IR 48 ± 3, p < 0.05). Additionally, decreased aortic ring sensitivity to ACh (pD2-value: -log 50% maximum response) seen after IR in the saline group was increased by DuraGraft® (pD2 to ACh: IR+Dura 7.1 ± 0.1 vs. IR 6.3 ± 0.2, p < 0.05). Impaired maximum contractile response to phenylephrine and high potassium chloride concentrations in the IR group compared to controls was significantly improved by DuraGraft®. DuraGraft® alleviates vascular dysfunction following IRI by reducing nitro-oxidative stress and the expression of ICAM-1, without leukocytes engagement.

scholarly journals Cardioprotective Effects of PPARβ/δ Activation against Ischemia/Reperfusion Injury in Rat Heart Are Associated with ALDH2 Upregulation, Amelioration of Oxidative Stress and Preservation of Mitochondrial Energy Production

2021 ◽  
Vol 22 (12) ◽  
pp. 6399
Author(s):  
Ioanna Papatheodorou ◽  
Eleftheria Galatou ◽  
Georgios-Dimitrios Panagiotidis ◽  
Táňa Ravingerová ◽  
Antigone Lazou
Keyword(s):  
Oxidative Stress ◽  
Mrna Expression ◽  
Energy Production ◽  
Citrate Synthase ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Uncoupling Protein ◽  
Ischemia Reperfusion ◽  
Left Ventricular ◽  
Isocitrate Dehydrogenase 2

Accumulating evidence support the cardioprotective properties of the nuclear receptor peroxisome proliferator activated receptor β/δ (PPARβ/δ); however, the underlying mechanisms are not yet fully elucidated. The aim of the study was to further investigate the mechanisms underlying PPARβ/δ-mediated cardioprotection in the setting of myocardial ischemia/reperfusion (I/R). For this purpose, rats were treated with PPARβ/δ agonist GW0742 and/or antagonist GSK0660 in vivo and hearts were subjected to ex vivo global ischemia followed by reperfusion. PPARβ/δ activation improved left ventricular developed pressure recovery, reduced infarct size (IS) and incidence of reperfusion-induced ventricular arrhythmias while it also up-regulated superoxide dismutase 2, catalase and uncoupling protein 3 resulting in attenuation of oxidative stress as evidenced by the reduction in 4-hydroxy-2-nonenal protein adducts and protein carbonyl formation. PPARβ/δ activation also increased both mRNA expression and enzymatic activity of aldehyde dehydrogenase 2 (ALDH2); inhibition of ALDH2 abrogated the IS limiting effect of PPARβ/δ activation. Furthermore, upregulation of PGC-1α and isocitrate dehydrogenase 2 mRNA expression, increased citrate synthase activity as well as mitochondrial ATP content indicated improvement in mitochondrial content and energy production. These data provide new mechanistic insight into the cardioprotective properties of PPARβ/δ in I/R pointing to ALDH2 as a direct downstream target and suggesting that PPARβ/δ activation alleviates myocardial I/R injury through coordinated stimulation of the antioxidant defense of the heart and preservation of mitochondrial function.

Abstract 235: Ischemia-Reperfusion Injury Decreases Myocardial Hydration Potential Without Changing Flow Resistance in the Interstitial Matrix

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Maria P McGee ◽  
Michael Morykwas ◽  
James Jordan ◽  
Louis Argenta
Keyword(s):  
At Risk ◽  
Flow Resistance ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Ischemia Reperfusion ◽  
P Value ◽  
Mechanical Forces ◽  
Interstitial Flow ◽  
Elastic Recoil ◽  
Fluid Accumulation

Interstitial edema is an early response to myocardial ischemia, leading to fibrosis and remodeling in several heart failure conditions. We aimed to clarify whether osmotic, frictional, or mechanical forces drive fluid accumulation. Equilibrium and dynamic interstitial hydration parameters were determined, compared, and analyzed using osmotic stress approaches in explants from ischemic and nonischemic myocardial regions of pig heart. They were isolated after injury induced by ligating 3-4 branches of the left anterior descending coronary artery, for 85 min followed by 3 hours’ reperfusion. Their volume changed (Δ V max ) linearly with colloidosmotic pressure in both ischemic and nonischemic areas, yielding interstitial compliance values of 1.04 ± 0.09 and 1.08 ± 0.05 µl/g/ mmHg , which do not differ significantly, and hydration potentials from the abscissa intercepts at Δ V max = 0, of -121.4 ± 28 and -14.7 ± 7.6 mmHg, which do (mean ± SE, n = 5 , P-value = 0.001). These hydration potential differences manifest ex-vivo influx rates 8.5 ± 2.7- fold slower in ischemic than nonischemic myocardium. Surprisingly, interstitial flow resistance values derived from net-flow rates at an imposed pressure difference of 216 mmHg were 0.23 ± 0.08 and 0.19 ± 0.01 µl -1 . g. min and did not differ significantly between the areas. The similarity in interstitial compliance and fluid resistance indicates that the more negative hydration potential and faster efflux rates in at-risk regions after reperfusion are due to increased hydrostatic pressure rather than decreased osmotic or frictional forces. Tissue distends due to interstitial fluid accumulation against matrix mechanical forces, including elastic recoil of the collagen elastin mesh and fibroblast action, consistent with impaired drainage and persistent diastolic-like conditions during reperfusion of at-risk areas in vivo . These results indicate changes in pressure gradient magnitude and may have clinical and therapeutic implications; for example, reversal of paracrine interstitial flows during early remodeling

scholarly journals Ex vivo carbon monoxide prevents cytochrome P450 degradation and ischemia/reperfusion injury of kidney grafts

2008 ◽  
Vol 74 (8) ◽  
pp. 1009-1016 ◽  
Author(s):  
Atsunori Nakao ◽  
Gaetano Faleo ◽  
Hiroko Shimizu ◽  
Kiichi Nakahira ◽  
Junichi Kohmoto ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Cytochrome P450 ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Ischemia Reperfusion

scholarly journals Baicalin Prevents Myocardial Ischemia/Reperfusion Injury Through Inhibiting ACSL4 Mediated Ferroptosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhenyu Fan ◽  
Liangliang Cai ◽  
Shengnan Wang ◽  
Jing Wang ◽  
Bohua Chen
Keyword(s):  
Myocardial Ischemia ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Systolic Pressure ◽  
Left Ventricular ◽  
Receptor Protein ◽  
H9c2 Cells ◽  
Myocardial Ischemia Reperfusion Injury ◽  
Myocardial Ischemia Reperfusion

Baicalin is a natural flavonoid glycoside that confers protection against myocardial ischemia/reperfusion (I/R) injury. However, its mechanism has not been fully understood. This study focused on elucidating the role of ferroptosis in baicalin-generated protective effects on myocardial ischemia/reperfusion (I/R) injury by using the myocardial I/R rat model and oxygen–glucose deprivation/reoxygenation (OGD/R) H9c2 cells. Our results show that baicalin improved myocardial I/R challenge–induced ST segment elevation, coronary flow (CF), left ventricular systolic pressure , infarct area, and pathological changes and prevented OGD/R-triggered cell viability loss. In addition, enhanced lipid peroxidation and significant iron accumulation along with activated transferrin receptor protein 1 (TfR1) signal and nuclear receptor coactivator 4 (NCOA4)-medicated ferritinophagy were observed in in vivo and in vitro models, which were reversed by baicalin treatment. Furthermore, acyl-CoA synthetase long-chain family member 4 (ACSL4) overexpression compromised baicalin-generated protective effect in H9c2 cells. Taken together, our findings suggest that baicalin prevents against myocardial ischemia/reperfusion injury via suppressing ACSL4-controlled ferroptosis. This study provides a novel target for the prevention of myocardial ischemia/reperfusion injury.

scholarly journals Normothermic Ex-vivo Kidney Perfusion in a Porcine Auto-Transplantation Model Preserves the Expression of Key Mitochondrial Proteins: An Unbiased Proteomics Analysis

2020 ◽  
Author(s):  
Caitriona M. McEvoy ◽  
Sergi Clotet-Freixas ◽  
Tomas Tokar ◽  
Chiara Pastrello ◽  
Shelby Reid ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Ischemia Reperfusion ◽  
Graft Function ◽  
Kidney Injury ◽  
Tca Cycle ◽  
Proteomics Analysis ◽  
Beneficial Effects ◽  
Kidney Perfusion

AbstractNormothermic ex-vivo kidney perfusion (NEVKP) results in significantly improved graft function in porcine auto-transplant models of DCD injury compared to static cold storage (SCS); however, the molecular mechanisms underlying these beneficial effects remain unclear. We performed an unbiased proteomics analysis of 28 kidney biopsies obtained at 3 time points from pig kidneys subjected to 30-minutes of warm ischemia, followed by 8 hours of NEVKP or SCS, and auto-transplantation. 70/6593 proteins quantified were differentially expressed between NEVKP and SCS groups (FDR<0.05). Proteins increased in NEVKP mediated key metabolic processes including fatty acid ß-oxidation, the TCA-cycle and oxidative phosphorylation. Comparison of our findings with external datasets of ischemia-reperfusion, and other models of kidney injury confirmed that 47 of our proteins represent a common signature of kidney injury reversed or attenuated by NEVKP. We validated key metabolic proteins (ETFB, CPT2) by immunoblotting. Transcription factor databases identified PPARGC1A, PPARA/G/D and RXRA/B as the upstream regulators of our dataset, and we confirmed their increased expression in NEVKP with RT-PCR. The proteome-level changes observed in NEVKP mediate critical metabolic pathways that may explain the improved graft function observed. These effects may be coordinated by PPAR-family transcription factors, and may represent novel therapeutic targets in ischemia-reperfusion injury.

scholarly journals mTOR‐mediated calcium transients affect cardiac function in ex vivo ischemia–reperfusion injury

2021 ◽  
Vol 9 (6) ◽  
Author(s):  
Briana K. Shimada ◽  
Naaiko Yorichika ◽  
Jason K. Higa ◽  
Yuichi Baba ◽  
Motoi Kobayashi ◽  
...  
Keyword(s):  
Cardiac Function ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Ischemia Reperfusion ◽  
Calcium Transients

scholarly journals STAT subtype specificity and ischemic preconditioning in mice: is STAT-3 enough?

2011 ◽  
Vol 300 (2) ◽  
pp. H522-H526 ◽  
Author(s):  
Michael D. Goodman ◽  
Sheryl E. Koch ◽  
Muhammad R. Afzal ◽  
Karyn L. Butler
Keyword(s):  
Ischemic Preconditioning ◽  
Ischemia Reperfusion Injury ◽  
Contractile Function ◽  
Ex Vivo ◽  
Ischemia Reperfusion ◽  
Cardiac Performance ◽  
Subtype Specificity ◽  
Developed Pressure ◽  
Perfused Hearts

The role of other STAT subtypes in conferring ischemic tolerance is unclear. We hypothesized that in STAT-3 deletion alternative STAT subtypes would protect myocardial function against ischemia-reperfusion injury. Wild-type (WT) male C57BL/6 mice or mice with cardiomyocyte STAT-3 knockout (KO) underwent baseline echocardiography. Langendorff-perfused hearts underwent ischemic preconditioning (IPC) or no IPC before ischemia-reperfusion. Following ex vivo perfusion, hearts were analyzed for STAT-5 and -6 phosphorylation by Western blot analysis of nuclear fractions. Echocardiography and postequilibration cardiac performance revealed no differences in cardiac function between WT and KO hearts. Phosphorylated STAT-5 and -6 expression was similar in WT and KO hearts before perfusion. Contractile function in WT and KO hearts was significantly impaired following ischemia-reperfusion in the absence of IPC. In WT hearts, IPC significantly improved the recovery of the maximum first derivative of developed pressure (+dP/d tmax) compared with that in hearts without IPC. IPC more effectively improved end-reperfusion dP/d tmax in WT hearts compared with KO hearts. Preconditioned and nonpreconditioned KO hearts exhibited increased phosphorylated STAT-5 and -6 expression compared with WT hearts. The increased subtype activation did not improve the efficacy of IPC in KO hearts. In conclusion, baseline cardiac performance is preserved in hearts with cardiac-restricted STAT-3 deletion. STAT-3 deletion attenuates preconditioning and is not associated with a compensatory upregulation of STAT-5 and -6 subtypes. The activation of STAT-5 and -6 in KO hearts following ischemic challenge does not provide functional compensation for the loss of STAT-3. JAK-STAT signaling via STAT-3 is essential for effective IPC.

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