scholarly journals Hydralazine protects the heart against acute ischaemia/reperfusion injury by inhibiting Drp1-mediated mitochondrial fission

2021 ◽  
Author(s):  
Siavash Beikoghli Kalkhoran ◽  
Janos Kriston-Vizi ◽  
Sauri Hernandez-Resendiz ◽  
Gustavo E Crespo-Avilan ◽  
Ayeshah A Rosdah ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Infarct Size ◽  
Myocardial Infarct ◽  
Mitochondrial Fission ◽  
Vehicle Control ◽  
Myocardial Infarct Size ◽  
Ischaemia Reperfusion Injury ◽  
Ischaemia Reperfusion ◽  
Pre Treatment ◽  
Apoptotic Effects

Abstract Aims Genetic and pharmacological inhibition of mitochondrial fission induced by acute myocardial ischaemia/reperfusion injury (IRI) has been shown to reduce myocardial infarct size. The clinically used anti-hypertensive and heart failure medication, hydralazine, is known to have anti-oxidant and anti-apoptotic effects. Here, we investigated whether hydralazine confers acute cardioprotection by inhibiting Drp1-mediated mitochondrial fission. Methods and results Pre-treatment with hydralazine was shown to inhibit both mitochondrial fission and mitochondrial membrane depolarisation induced by oxidative stress in HeLa cells. In mouse embryonic fibroblasts (MEFs), pre-treatment with hydralazine attenuated mitochondrial fission and cell death induced by oxidative stress, but this effect was absent in MEFs deficient in the mitochondrial fission protein, Drp1. Molecular docking and surface plasmon resonance studies demonstrated binding of hydralazine to the GTPase domain of the mitochondrial fission protein, Drp1 (KD 8.6±1.0 µM), and inhibition of Drp1 GTPase activity in a dose-dependent manner. In isolated adult murine cardiomyocytes subjected to simulated IRI, hydralazine inhibited mitochondrial fission, preserved mitochondrial fusion events, and reduced cardiomyocyte death (hydralazine 24.7±2.5% vs. control 34.1±1.5%, P=0.0012). In ex vivo perfused murine hearts subjected to acute IRI, pre-treatment with hydralazine reduced myocardial infarct size (as % left ventricle: hydralazine 29.6±6.5% vs. vehicle control 54.1±4.9%, P=0.0083), and in the murine heart subjected to in vivo IRI, the administration of hydralazine at reperfusion, decreased myocardial infarct size (as % area-at-risk: hydralazine 28.9±3.0% vs. vehicle control 58.2±3.8%, P<0.001). Conclusion We show that, in addition to its antioxidant and anti-apoptotic effects, hydralazine, confers acute cardioprotection by inhibiting IRI-induced mitochondrial fission, raising the possibility of repurposing hydralazine as a novel cardioprotective therapy for improving post-infarction outcomes.

scholarly journals Remote Limb Ischaemic Postconditioning Protects Against Myocardial Ischaemia/Reperfusion Injury in Mice: Activation of JAK/STAT3-Mediated Nrf2-Antioxidant Signalling

2017 ◽  
Vol 43 (3) ◽  
pp. 1140-1151 ◽  
Author(s):  
Sumin Gao ◽  
Leyun Zhan ◽  
Zhengchao Yang ◽  
Ruili Shi ◽  
Haobo Li ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Infarct Size ◽  
Myocardial Ischaemia ◽  
Nuclear Translocation ◽  
Myocardial Infarct ◽  
Myocardial Infarct Size ◽  
Enzyme Release ◽  
Ischaemia Reperfusion ◽  
Myocardial Oxidative Stress ◽  
Creatine Kinase Mb

Background: This study aimed to evaluate the protective effect and mechanisms of remote limb ischaemic postconditioning (RIPostC) against myocardial ischaemia/reperfusion (IR) injury. Methods: Male mice underwent 45 min of coronary artery occlusion followed by 2 h of reperfusion. RIPostC was achieved by three cycles of 5 min of ischaemia and 5 min of reperfusion in the left hind limb at the start of the reperfusion period. After 2 h of cardiac reperfusion, myocardial infarct size, cardiac enzyme release, apoptosis and oxidative stress were assessed. Protein expression and phosphorylation were measured by Western blotting. Results: RIPostC significantly decreased cardiac IR injury, as reflected by reduced infarct size and cellular apoptosis (22.9 ± 3.3% vs 40.9 ± 6.2% and 13.4% ± 3.1% vs 26.2% ± 3.1%, respectively, both P < 0.01) as well as plasma creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) release (21.97 ± 4.08 vs 35.86 ± 2.91 ng/ml and 6.17 ± 0.58 vs 8.37 ± 0.89 U/ml, respectively, both P < 0.01) compared with the IR group. RIPostC significantly increased the phosphorylation of myocardial STAT3, Akt and eNOS (P < 0.01). In addition, RIPostC elevated the nuclear translocation of Nrf2 and the expression of HO-1 and reduced myocardial oxidative stress (P < 0.05). Interestingly, pretreatment with the JAK/STAT3 inhibitor AG490 blocked the cardioprotective effect of RIPostC accompanied by decreased phosphorylation of myocardial STAT3, Akt and eNOS (P < 0.05), decreased nuclear translocation of Nrf2 and expression of HO-1, as well as increased oxidative stress (P < 0.05). Conclusion: RIPostC attenuates apoptosis and protects against myocardial IR injury, possibly through the activation of JAK/STAT3-mediated Nrf2-antioxidant signalling.

scholarly journals Diabetes impairs the protective effects of sevoflurane postconditioning in myocardium subjected to ischemia/reperfusion injury in rats: important role of Drp1

2020 ◽  
Author(s):  
Jing Yu ◽  
Jiandong He ◽  
Wenqu Yang ◽  
Xiang Wang ◽  
Gaoxiang Shi ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Infarct Size ◽  
Myocardial Infarct ◽  
Ischemia Reperfusion ◽  
Mitochondrial Fission ◽  
Myocardial Infarct Size ◽  
Diabetic Myocardium ◽  
Sevoflurane Postconditioning ◽  
And Oxidative Stress

Abstract Background Sevoflurane postconditioning (SevP) is an effective way in relieving myocardial ischemia/reperfusion (IR) injury, which doesn’t work well in diabetic myocardium unfortunately. Prior studies have noted the importance of increasing oxidative stress in diabetic tissues. Noteworthily, mitochondrial fission mediated by dynamin-related protein 1 (Drp1) is an upstream pathway of reactive oxygen production. Whether Drp1 dependent mitochondrial fission is associated with the ineffectiveness of SevP in diabetic myocardium remains unknown. The aim of this study was to explore the important role of Drp1 in diabetic myocardium and investigate whether Drp1 inhibition could restore the cardioprotective effect of SevP. Methods In the first part, adult male Sprague-Dawley(SD) rats were divided into 6 groups. Rats in diabetic groups were fed with high-fat and high-sugar for 8 weeks, and then received a injection of streptozotocin (35 mg/kg) intraperitoneally. Myocardial IR was induced by 30 min occlusion of left anterior descending branch of coronary artery followed by 120 min reperfusion༎SevP was applied by continuous inhalation of 2.5% sevoflurane 1 min before reperfusion, which lasted for 10 min. In the second part, mdivi-1 was used to investigate whether Drp1 inhibition could restore the cardioprotective effects of SevP in diabetic myocardium against I/R injury. The myocardial infarct size, pathology, mitochondrial ultrastructure, cardiomyocyte apoptosis, total SOD activity, MDA content, and Drp1 expression were detected. Results The diabetic myocardium displayed severer injury with greater infarct size and apoptosis. Up-regulated Drp1 expression concomitant with increased mitochondrial fission and oxidative stress were observed in diabetic myocardium subjected to I/R. The deteriorated changes were alleviated in normal but not in diabetic rats. Importantly, mdivi-1 administration significantly suppressed mitochondrial fission and oxidative stress, and the beneficial effects of SevP were restored by mdivi-1. Conclusions The present study indicates a crucial role of Drp1 dependent mitochondrial fission in diabetic myocardium subjected to IR. Drp1 inhibition may be effective in restoring the effect of SevP in reducing diabetic myocardial IR injury.

scholarly journals Human thrombopoietin reduces myocardial infarct size, apoptosis, and stunning following ischaemia/reperfusion in rats

2007 ◽  
Vol 77 (1) ◽  
pp. 44-53 ◽  
Author(s):  
J. E. Baker ◽  
J. Su ◽  
A. Hsu ◽  
Y. Shi ◽  
M. Zhao ◽  
...  
Keyword(s):  
Infarct Size ◽  
Myocardial Infarct ◽  
Myocardial Infarct Size ◽  
Ischaemia Reperfusion

Postconditioning attenuates myocardial injury by reducing nitro-oxidative stress in vivo in rats and in humans

2010 ◽  
Vol 120 (6) ◽  
pp. 251-261 ◽  
Author(s):  
Qian Fan ◽  
Xin-Chun Yang ◽  
Yu Liu ◽  
Le-Feng Wang ◽  
Sheng-Hui Liu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cardiac Function ◽  
Myocardial Infarct ◽  
White Blood Cells ◽  
Coronary Intervention ◽  
Myocardial Infarct Size ◽  
Ischaemia Reperfusion Injury ◽  
Acute Myocardial Infarct ◽  
Inos Activity

In the present study, we hypothesized that postcon (postconditioning) confers cardioprotection in vivo by reducing the production of ONOO− (peroxynitrite) and nitro-oxidative stress subsequent to the inhibition of the iNOS (inducible NO synthase). Patients with AMI (acute myocardial infarct) were randomly assigned to undergo percutaneous coronary intervention without (control) or with ischaemic postcon by three episodes of 30-s inflation and 30-s deflation of the angioplasty balloon. Animal models of MI/R (myocardial ischaemia/reperfusion) injury were induced in rats by occluding the left coronary artery for 40 min followed by 4-h reperfusion. Rats were randomized to receive vehicle, postcon (three cycles of 10-s reperfusion and 10-s coronary re-occlusion preceding full reperfusion), the selective iNOS inhibitor 1400W or postcon plus 3-morpholinosydnonimine (an ONOO− donor). Postcon in patients reduced iNOS activity in white blood cells, decreased plasma nitrotyrosine, a fingerprint of ONOO− and an index of nitro-oxidative stress, and improved cardiac function (P<0.01 compared with control). In rats, postcon reduced post-ischaemic myocardial iNOS activity and nitrotyrosine formation, reduced myocardial infarct size (all P<0.05 compared with control) and improved cardiac function. Administration of 1400W resembled, whereas 3-morpholinosydnonimine abolished, the effects of postcon. In conclusion, reduction in ONOO−-induced nitro-oxidative stress subsequent to the inhibition of iNOS represents a major mechanism whereby postcon confers cardioprotection in vivo.

scholarly journals Loss of Protein Kinase Novel 1 (PKN1) is associated with mild systolic and diastolic contractile dysfunction, increased phospholamban Thr17 phosphorylation, and exacerbated ischaemia-reperfusion injury

2017 ◽  
Vol 114 (1) ◽  
pp. 138-157 ◽  
Author(s):  
Asvi A Francois ◽  
Kofo Obasanjo-Blackshire ◽  
James E Clark ◽  
Andrii Boguslavskyi ◽  
Mark R Holt ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Infarct Size ◽  
Cell Injury ◽  
Contractile Function ◽  
Myocardial Infarct ◽  
Neonatal Rat ◽  
Myocardial Infarct Size ◽  
Ischaemia Reperfusion ◽  
Sirna Knockdown

Abstract Aims PKN1 is a stress-responsive protein kinase acting downstream of small GTP-binding proteins of the Rho/Rac family. The aim was to determine its role in endogenous cardioprotection. Methods and results Hearts from PKN1 knockout (KO) or wild type (WT) littermate control mice were perfused in Langendorff mode and subjected to global ischaemia and reperfusion (I/R). Myocardial infarct size was doubled in PKN1 KO hearts compared to WT hearts. PKN1 was basally phosphorylated on the activation loop Thr778 PDK1 target site which was unchanged during I/R. However, phosphorylation of p42/p44-MAPK was decreased in KO hearts at baseline and during I/R. In cultured neonatal rat ventricular cardiomyocytes (NRVM) and NRVM transduced with kinase dead (KD) PKN1 K644R mutant subjected to simulated ischaemia/reperfusion (sI/R), PhosTag® gel analysis showed net dephosphorylation of PKN1 during sI and early R despite Thr778 phosphorylation. siRNA knockdown of PKN1 in NRVM significantly decreased cell survival and increased cell injury by sI/R which was reversed by WT- or KD-PKN1 expression. Confocal immunofluorescence analysis of PKN1 in NRVM showed increased localization to the sarcoplasmic reticulum (SR) during sI. GC-MS/MS and immunoblot analysis of PKN1 immunoprecipitates following sI/R confirmed interaction with CamKIIδ. Co-translocation of PKN1 and CamKIIδ to the SR/membrane fraction during sI correlated with phospholamban (PLB) Thr17 phosphorylation. siRNA knockdown of PKN1 in NRVM resulted in increased basal CamKIIδ activation and increased PLB Thr17 phosphorylation only during sI. In vivo PLB Thr17 phosphorylation, Sarco-Endoplasmic Reticulum Ca2+ ATPase (SERCA2) expression and Junctophilin-2 (Jph2) expression were also basally increased in PKN1 KO hearts. Furthermore, in vivo P-V loop analysis of the beat-to-beat relationship between rate of LV pressure development or relaxation and end diastolic P (EDP) showed mild but significant systolic and diastolic dysfunction with preserved ejection fraction in PKN1 KO hearts. Conclusion Loss of PKN1 in vivo significantly reduces endogenous cardioprotection and increases myocardial infarct size following I/R injury. Cardioprotection by PKN1 is associated with reduced CamKIIδ-dependent PLB Thr17 phosphorylation at the SR and therefore may stabilize the coupling of SR Ca2+ handling and contractile function, independent of its kinase activity.

Reciprocalcation of caveolin and HSP-72 on IPC interceded cardio-protection in the orchidectomized rats

2021 ◽  
Vol 12 (1) ◽  
pp. 683-689
Author(s):  
Ritesh Kumar Srivastav ◽  
Tarique Mahmood Ansari ◽  
Mahesh Prasad ◽  
Vishal Kumar Vishwakarma ◽  
Shravan Kumar Paswan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Infarct Size ◽  
Myocardial Infarct ◽  
Male Rats ◽  
Oxidative Stress Marker ◽  
Myocardial Infarct Size ◽  
Perfused Heart ◽  
Oxidative Stress Parameter ◽  
Cardio Protection ◽  
And Oxidative Stress

Diminished testosterone levels conjoined to cardiovascular risk factor mainly myocardial infarction which broadens the risk of cardiovascular mortality referring to age. Ischemic preconditioning (IPC) is one of the interventions to shield such injury. The present study implicated the possible involvement of caveolin and heat shock protein 72 (HSP-72) during stress in orchidectomy (OCD) challenged rats. OCD was performed in male rats and kept for 6 weeks to observe the reduction in the level of testosterone. Isolated perfused heart of normal and OCD group was subjected to ischemic insult as per IPC cycle. Myocardial infarct size, haemodynamic, enzymatic and oxidative stress parameter were assessed for each heart. Diadzein (DDZ) a caveolin inhibitor was administered before the isolation of heart and it significantly decreases myocardial infarct size, release of lactate dehydrogenase, creatinine kinase and oxidative stress marker. DDZ also potentiated the effect IPC-mediated increase in the heart rate and coronary flow. The effect of caveolin inhibitor was remarkably reduced by quercetin administered before 1 h. of the administration DDZ. The findings of this study revealed that protection of myocardium induced by caveolin inhibitor pretreatment has not been lost in OCD rat heart.

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