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Oberdier MT, Li J, Ambinder DI, Suzuki M, Tumarkin E, Fink S, Neri L, Zhu X, Justice CN, Vanden Hoek TL, Halperin HR. Survival and Neurologic Outcomes From Pharmacologic Peptide Administration During Cardiopulmonary Resuscitation of Pulseless Electrical Activity. J Am Heart Assoc 2024; 13:e9757. [PMID: 38934857 PMCID: PMC11255698 DOI: 10.1161/jaha.123.033371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 05/08/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND Outcomes from cardiopulmonary resuscitation (CPR) following sudden cardiac arrest are suboptimal. Postresuscitation targeted temperature management has been shown to have benefit in subjects with sudden cardiac arrest due to ventricular fibrillation, but there are few data for outcomes from sudden cardiac arrest due to pulseless electrical activity. In addition, intra-CPR cooling is more effective than postresuscitation cooling. Physical cooling is associated with increased protein kinase B activity. Therefore, our group developed a novel peptide, TAT-PHLPP9c, which regulates protein kinase B. We hypothesized that when given during CPR, TAT-PHLPP9c would improve survival and neurologic outcomes following pulseless electrical activity arrest. METHODS AND RESULTS In 24 female pigs, pulseless electrical activity was induced by inflating balloon catheters in the right coronary and left anterior descending arteries for ≈7 minutes. Advanced life support was initiated. In 12 control animals, epinephrine was given after 1 and 3 minutes. In 12 peptide-treated animals, 7.5 mg/kg TAT-PHLPP9c was also administered at 1 and 3 minutes of CPR. The balloons were removed after 2 minutes of support. Animals were recovered and neurologically scored 24 hours after return of spontaneous circulation. Return of spontaneous circulation was more common in the peptide group, but this difference was not significant (8/12 control versus 12/12 peptide; P=0.093), while fully intact neurologic survival was significantly more common in the peptide group (0/12 control versus 11/12 peptide; P<0.00001). TAT-PHLPP9c significantly increased myocardial nicotinamide adenine dinucleotide levels. CONCLUSIONS TAT-PHLPP9c resulted in improved survival with full neurologic function after sudden cardiac arrest in a swine model of pulseless electrical activity, and the peptide shows potential as an intra-CPR pharmacologic agent.
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Affiliation(s)
| | - Jing Li
- University of Illinois – ChicagoChicagoIL
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Zhu X, Li J, Wang H, Gasior FM, Lee C, Lin S, Justice CN, O’Donnell JM, Vanden Hoek TL. Nicotinamide restores tissue NAD+ and improves survival in rodent models of cardiac arrest. PLoS One 2023; 18:e0291598. [PMID: 37713442 PMCID: PMC10503771 DOI: 10.1371/journal.pone.0291598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 09/04/2023] [Indexed: 09/17/2023] Open
Abstract
Metabolic suppression in the ischemic heart is characterized by reduced levels of NAD+ and ATP. Since NAD+ is required for most metabolic processes that generate ATP, we hypothesized that nicotinamide restores ischemic tissue NAD+ and improves cardiac function in cardiomyocytes and isolated hearts, and enhances survival in a mouse model of cardiac arrest. Mouse cardiomyocytes were exposed to 30 min simulated ischemia and 90 min reperfusion. NAD+ content dropped 40% by the end of ischemia compared to pre-ischemia. Treatment with 100 μM nicotinamide (NAM) at the start of reperfusion completely restored the cellular level of NAD+ at 15 min of reperfusion. This rescue of NAD+ depletion was associated with improved contractile recovery as early as 10 min post-reperfusion. In a mouse model of cardiac arrest, 100 mg/kg NAM administered IV immediately after cardiopulmonary resuscitation resulted in 100% survival at 4 h as compared to 50% in the saline group. In an isolated rat heart model, the effect of NAM on cardiac function was measured for 20 min following 18 min global ischemia. Rate pressure product was reduced by 26% in the control group following arrest. Cardiac contractile function was completely recovered with NAM treatment given at the start of reperfusion. NAM restored tissue NAD+ and enhanced production of lactate and ATP, while reducing glucose diversion to sorbitol in the heart. We conclude that NAM can rapidly restore cardiac NAD+ following ischemia and enhance glycolysis and contractile recovery, with improved survival in a mouse model of cardiac arrest.
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Affiliation(s)
- Xiangdong Zhu
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Jing Li
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Huashan Wang
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Filip M. Gasior
- Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Chunpei Lee
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Shaoxia Lin
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Cody N. Justice
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
- Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - J. Michael O’Donnell
- Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
| | - Terry L. Vanden Hoek
- Center for Advanced Resuscitation Medicine and Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois, United States of America
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Bian W, Bian W, Li Y, Feng X, Song M, Zhou P. Hypothermia may reduce mortality and improve neurologic outcomes in adult patients treated with VA-ECMO: A systematic review and meta-analysis. Am J Emerg Med 2023; 70:163-170. [PMID: 37327682 DOI: 10.1016/j.ajem.2023.05.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/08/2023] [Accepted: 05/21/2023] [Indexed: 06/18/2023] Open
Abstract
BACKGROUND VA-ECMO can greatly reduce mortality in critically ill patients, and hypothermia attenuates the deleterious effects of ischemia-reperfusion injury. We aimed to study the effects of hypothermia on mortality and neurological outcomes in VA-ECMO patients. METHODS A systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases was performed from the earliest available date to 31 December 2022. The primary outcome was discharge or 28-day mortality and favorable neurological outcomes in VA-ECMO patients, and the secondary outcome was bleeding risk in VA-ECMO patients. The results are presented as odds ratios (ORs) and 95% confidence intervals (CIs). Based on the heterogeneity assessed by the I2 statistic, meta-analyses were performed using random or fixed-effects models. GRADE methodology was used to rate the certainty in the findings. RESULTS A total of 27 articles (3782 patients) were included. Hypothermia (33-35 °C) lasting at least 24 h can significantly reduce discharge or 28-day mortality (OR, 0.45; 95% CI, 0.33-0.63; I2 = 41%) and significantly improve favorable neurological outcomes (OR, 2.08; 95% CI, 1.66-2.61; I2 = 3%) in VA-ECMO patients. Additionally, there was no risk associated with bleeding (OR, 1.15; 95% CI, 0.86-1.53; I2 = 12%). In our subgroup analysis according to in-hospital or out-of-hospital cardiac arrest, hypothermia reduced short-term mortality in both VA-ECMO-assisted in-hospital (OR, 0.30; 95% CI, 0.11-0.86; I2 = 0.0%) and out-of-hospital cardiac arrest (OR, 0.41; 95% CI, 0.25-0.69; I2 = 52.3%). Out-of-hospital cardiac arrest patients assisted by VA-ECMO for favorable neurological outcomes were consistent with the conclusions of this paper (OR, 2.10; 95% CI, 1.63-2.72; I2 = 0.5%). CONCLUSIONS Our results show that mild hypothermia (33-35 °C) lasting at least 24 h can greatly reduce short-term mortality and significantly improve favorable short-term neurologic outcomes in VA-ECMO-assisted patients without bleeding-related risks. As the grade assessment indicated that the certainty of the evidence was relatively low, hypothermia as a strategy for VA-ECMO-assisted patient care may need to be treated with caution.
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Affiliation(s)
- Wentao Bian
- School of Clinical Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province, China
| | - Wenkai Bian
- Xi'an Radio Research Institute, Xian, Shaanxi Province, China
| | - Yi Li
- Emergency Intensive Care Unit, Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China
| | - Xuanlin Feng
- Emergency Intensive Care Unit, Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China
| | - Menglong Song
- Emergency Intensive Care Unit, Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China
| | - Ping Zhou
- Emergency Intensive Care Unit, Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, China.
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Li J, Zhu X, Oberdier MT, Lee C, Lin S, Fink SJ, Justice CN, Qin K, Begeman AW, Damen FC, Kim H, Chen J, Cai K, Halperin HR, Vanden Hoek TL. A cell-penetrating PHLPP peptide improves cardiac arrest survival in murine and swine models. J Clin Invest 2023; 133:e164283. [PMID: 37115695 PMCID: PMC10145924 DOI: 10.1172/jci164283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 02/16/2023] [Indexed: 04/29/2023] Open
Abstract
Out-of-hospital cardiac arrest is a leading cause of death in the US, with a mortality rate over 90%. Preclinical studies demonstrate that cooling during cardiopulmonary resuscitation (CPR) is highly beneficial, but can be challenging to implement clinically. No medications exist for improving long-term cardiac arrest survival. We have developed a 20-amino acid peptide, TAT-PHLPP9c, that mimics cooling protection by enhancing AKT activation via PH domain leucine-rich repeat phosphatase 1 (PHLPP1) inhibition. Complementary studies were conducted in mouse and swine. C57BL/6 mice were randomized into blinded saline control and peptide-treatment groups. Following a 12-minute asystolic arrest, TAT-PHLPP9c was administered intravenously during CPR and significantly improved the return of spontaneous circulation, mean arterial blood pressure and cerebral blood flow, cardiac and neurological function, and survival (4 hour and 5 day). It inhibited PHLPP-NHERF1 binding, enhanced AKT but not PKC phosphorylation, decreased pyruvate dehydrogenase phosphorylation and sorbitol production, and increased ATP generation in heart and brain. TAT-PHLPP9c treatment also reduced plasma taurine and glutamate concentrations after resuscitation. The protective benefit of TAT-PHLPP9c was validated in a swine cardiac arrest model of ventricular fibrillation. In conclusion, TAT-PHLPP9c may improve neurologically intact cardiac arrest survival without the need for physical cooling.
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Affiliation(s)
- Jing Li
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Xiangdong Zhu
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Matt T. Oberdier
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Chunpei Lee
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Shaoxia Lin
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Sarah J. Fink
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Cody N. Justice
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Kevin Qin
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Andrew W. Begeman
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | | | - Hajwa Kim
- Center for Clinical and Translational Science
| | - Jiwang Chen
- Cardiovascular Research Center, and
- Department of Medicine, Division of Pulmonary, Critical Care, Sleep and Allergy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Kejia Cai
- Department of Radiology, College of Medicine
| | - Henry R. Halperin
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
- Departments of Radiology and Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Terry L. Vanden Hoek
- Center for Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois, USA
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5
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Justice CN, Zhu X, Li J, O'Donnell JM, Vanden Hoek TL. Intra-ischemic hypothermia cardioprotection involves modulation of PTEN/Akt/ERK signaling and fatty acid oxidation. Physiol Rep 2023; 11:e15611. [PMID: 36807889 PMCID: PMC9938006 DOI: 10.14814/phy2.15611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 02/20/2023] Open
Abstract
Therapeutic hypothermia (TH) provides cardioprotection from ischemia/reperfusion (I/R) injury. However, it remains unknown how TH regulates metabolic recovery. We tested the hypothesis that TH modulates PTEN, Akt, and ERK1/2, and improves metabolic recovery through mitigation of fatty acid oxidation and taurine release. Left ventricular function was monitored continuously in isolated rat hearts subjected to 20 min of global, no-flow ischemia. Moderate cooling (30°C) was applied at the start of ischemia and hearts were rewarmed after 10 min of reperfusion. The effect of TH on protein phosphorylation and expression at 0 and 30 min of reperfusion was investigated by western blot analysis. Post-ischemic cardiac metabolism was investigated by 13 C-NMR. TH enhanced recovery of cardiac function, reduced taurine release, and enhanced PTEN phosphorylation and expression. Phosphorylation of Akt and ERK1/2 was increased at the end of ischemia but decreased at the end of reperfusion. On NMR analysis, TH-treated hearts displayed decreased fatty acid oxidation. Direct cardioprotection by moderate intra-ischemic TH is associated with decreased fatty acid oxidation, reduced taurine release, enhanced PTEN phosphorylation and expression, and enhanced activation of both Akt and ERK1/2 prior to reperfusion.
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Affiliation(s)
- Cody N. Justice
- Center for Advanced Resuscitation Medicine, Department of Emergency MedicineUniversity of Illinois at ChicagoChicagoIllinoisUSA,Department of Physiology and BiophysicsUniversity of Illinois at ChicagoChicagoIllinoisUSA,Center for Cardiovascular ResearchUniversity of Illinois at ChicagoChicagoIllinoisUSA
| | - Xiangdong Zhu
- Center for Advanced Resuscitation Medicine, Department of Emergency MedicineUniversity of Illinois at ChicagoChicagoIllinoisUSA,Center for Cardiovascular ResearchUniversity of Illinois at ChicagoChicagoIllinoisUSA
| | - Jing Li
- Center for Advanced Resuscitation Medicine, Department of Emergency MedicineUniversity of Illinois at ChicagoChicagoIllinoisUSA,Center for Cardiovascular ResearchUniversity of Illinois at ChicagoChicagoIllinoisUSA
| | - J. Michael O'Donnell
- Department of Physiology and BiophysicsUniversity of Illinois at ChicagoChicagoIllinoisUSA,Center for Cardiovascular ResearchUniversity of Illinois at ChicagoChicagoIllinoisUSA
| | - Terry L. Vanden Hoek
- Center for Advanced Resuscitation Medicine, Department of Emergency MedicineUniversity of Illinois at ChicagoChicagoIllinoisUSA,Department of Physiology and BiophysicsUniversity of Illinois at ChicagoChicagoIllinoisUSA,Center for Cardiovascular ResearchUniversity of Illinois at ChicagoChicagoIllinoisUSA
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Hypothermia Prevents Cardiac Dysfunction during Acute Ischemia Reperfusion by Maintaining Mitochondrial Bioenergetics and by Promoting Hexokinase II Binding to Mitochondria. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:4476448. [PMID: 35873800 PMCID: PMC9301761 DOI: 10.1155/2022/4476448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 03/04/2022] [Accepted: 06/14/2022] [Indexed: 11/18/2022]
Abstract
Background Hypothermia (H), cardioplegia (CP), and both combined (HCP) are known to be protective against myocardial ischemia reperfusion (IR) injury. Mitochondria have molecular signaling mechanisms that are associated with both cell survival and cell death. In this study, we investigated the dynamic changes in proapoptotic and prosurvival signaling pathways mediating H, CP, or HCP-induced protection of mitochondrial function after acute myocardial IR injury. Methods Rats were divided into five groups. Each group consists of 3 subgroups based on a specific reperfusion time (5, 20, or 60 min) after a 25-min global ischemia. The time control (TC) groups were not subjected to IR but were perfused with 37 °C Krebs-Ringer's (KR) buffer, containing 4.5 mM K+, in a specific perfusion protocol that corresponded with the duration of each IR protocol. The IR group (control) was perfused for 20 min with KR, followed by 25-min global ischemia, and then KR reperfusion for 5, 20, or 60 min. The treatment groups were exposed to 17 °C H, 37 °C CP (16 mM K+), or HCP (17 °C + CP) for 5 min before ischemia and for 2 min on reperfusion before switching to 37 °C KR perfusion for the remainder of each of the reperfusion times. Cardiac function and mitochondrial redox state (NADH/FAD) were monitored online in the ex vivo hearts before, during, and after ischemia. Mitochondria were isolated at the end of each specified reperfusion time, and changes in O2 consumption, membrane potential (ΔΨm), and Ca2+ retention capacity (CRC) were assessed using complex I and complex II substrates. In another set of hearts, mitochondrial and cytosolic fractions were isolated after a specified reperfusion time to conduct western blot assays to determine hexokinase II (HKII) and Bax binding/translocation to mitochondria, cytosolic pAkt levels, and cytochrome c (Cyto-c) release into the cytosol. Results H and HCP were more protective of mitochondrial integrity and, concomitantly, cardiac function than CP alone; H and HCP improved post-ischemic cardiac function by (1) maintaining mitochondrial bioenergetics, (2) maintaining HKII binding to mitochondria with an increase in pAkt levels, (3) increasing CRC, and (4) decreasing Cyto-c release during reperfusion. Bax translocation/binding to mitochondria was unaffected by any treatment, regardless of cardiac functional recovery. Conclusions Hypothermia preserved mitochondrial function and cardiac function, in part, by maintaining mitochondrial bioenergetics, by retaining HKII binding to mitochondria via upstream pAkt, and by reducing Cyto-c release independently of Bax binding to mitochondria.
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Zhu X, Li J, Wang H, Gasior FM, Lee C, Lin S, Zhu Z, Wang Y, Justice CN, O'Donnell JM, Vanden Hoek TL. TAT delivery of a PTEN peptide inhibitor has direct cardioprotective effects and improves outcomes in rodent models of cardiac arrest. Am J Physiol Heart Circ Physiol 2021; 320:H2034-H2043. [PMID: 33834871 DOI: 10.1152/ajpheart.00513.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have recently shown that pharmacologic inhibition of PTEN significantly increases cardiac arrest survival in a mouse model, however, this protection required pretreatment 30 min before the arrest. To improve the onset of PTEN inhibition during cardiac arrest treatment, we have designed a TAT fused cell-permeable peptide (TAT-PTEN9c) based on the C-terminal PDZ binding motif of PTEN for rapid tissue delivery and protection. Western blot analysis demonstrated that TAT-PTEN9c peptide significantly enhanced Akt activation in mouse cardiomyocytes in a concentration- and time-dependent manner. Mice were subjected to 8 min asystolic arrest followed by CPR, and 30 mice with successful CPR were then randomly assigned to receive either saline or TAT-PTEN9c treatment. Survival was significantly increased in TAT-PTEN9c-treated mice compared with that of saline control at 4 h after CPR. The treated mice had increased Akt phosphorylation at 30 min resuscitation with significantly decreased sorbitol content in heart or brain tissues and reduced release of taurine and glutamate in blood, suggesting improved glucose metabolism. In an isolated rat heart Langendorff model, direct effects of TAT-PTEN9c on cardiac function were measured for 20 min following 20 min global ischemia. Rate pressure product was reduced by >20% for both TAT vehicle and nontreatment groups following arrest. Cardiac contractile function was completely recovered with TAT-PTEN9c treatment given at the start of reperfusion. We conclude that TAT-PTEN9c enhances Akt activation and decreases glucose shunting to the polyol pathway in critical organs, thereby preventing osmotic injury and early cardiovascular collapse and death.NEW & NOTEWORTHY We have designed a cell-permeable peptide, TAT-PTEN9c, to improve cardiac arrest survival. It blocked endogenous PTEN binding to its adaptor and enhanced Akt signaling in mouse cardiomyocytes. It improved mouse survival after cardiac arrest, which is related to improved glucose metabolism and reduced glucose shunting to sorbitol in critical organs.
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Affiliation(s)
- Xiangdong Zhu
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Jing Li
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Huashan Wang
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | | | - Chunpei Lee
- Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Shaoxia Lin
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Zhiyi Zhu
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Youhua Wang
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Cody N Justice
- Program in Advanced Resuscitation Medicine, Department of Emergency Medicine, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois.,Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - J Michael O'Donnell
- Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
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Akt1-mediated CPR cooling protection targets regulators of metabolism, inflammation and contractile function in mouse cardiac arrest. PLoS One 2019; 14:e0220604. [PMID: 31398213 PMCID: PMC6688812 DOI: 10.1371/journal.pone.0220604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 07/21/2019] [Indexed: 12/31/2022] Open
Abstract
Therapeutic hypothermia initiated during cardiopulmonary resuscitation (CPR) in pre-clinical studies appears to be highly protective against sudden cardiac arrest injury. Given the challenges to implementing CPR cooling clinically, insights into its critical mechanisms of protection could guide development of new CPR drugs that mimic hypothermia effects without the need for physical cooling. Here, we used Akt1-deficient mice that lose CPR hypothermia protection to identify hypothermia targets. Adult female C57BL/6 mice (Akt1+/+ and Akt1+/-) underwent 8 min of KCl-induced asystolic arrest and were randomized to receive hypothermia (30 ± 0.5°C) or normothermia. Hypothermia was initiated during CPR and extended for 1 h after resuscitation. Neurologically scored survival was measured at 72 h. Other outcomes included mean arterial pressure and target measures in heart and brain related to contractile function, glucose utilization and inflammation. Compared to northothermia, hypothermia improved both 2h mean arterial pressure and 72h neurologically intact survival in Akt1+/+ mice but not in Akt1+/- mice. In Akt1+/+ mice, hypothermia increased Akt and GSK3β phosphorylation, pyruvate dehydrogenase activation, and NAD+ and ATP production while decreasing IκBα degradation and NF-κB activity in both heart and brain at 30 min after CPR. It also increased phospholamban phosphorylation in heart tissue. Further, hypothermia reduced metabolic and inflammatory blood markers lactate and Pre-B cell Colony Enhancing Factor. Despite hypothermia treatment, all these effects were reversed in Akt1+/- mice. Taken together, drugs that target Akt1 and its effectors may have the potential to mimic hypothermia-like protection to improve sudden cardiac arrest survival when administered during CPR.
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Li Z, Cheng Z, Haifeng Y, Chen M, Li L. PTEN signaling inhibitor VO-OHpic improves cardiac myocyte survival by mediating apoptosis resistance in vitro. Biomed Pharmacother 2018; 103:1217-1222. [PMID: 29864901 DOI: 10.1016/j.biopha.2018.04.141] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 10/17/2022] Open
Abstract
BACKGROUND Acute myocardial infarction (AMI) is a server disease effecting a large population worldwide. The pathophysiological process of ischemic/reperfusion (I/R) plays an important role for heart tissue damage. VO-OHpic, a PTEN inhibitor, has been demonstrated to be cardiac protective in sudden cardiac arrest models, but its role in AMI remains unclear. METHODS An isolated AMI model was induced by dissecting the rat heart in a Langendorff system. Cardiac myocytes were extracted and induced ischemia in vitro. VO-OHpic was added into the above systems. The area of infarcted tissue in the heart was measured. Cardiac myocyte apoptosis was assessed by flow cytometry. Activation of Akt and GSK3β was quantified by flow cytometry. IL-10 levels were determined by ELISA. RESULTS VO-OHpic reduced infarcted areas in the isolated heart, and improved cultured cardiac myocyte survival. VO-OHpic induced apoptosis resistance in cardiac myocytes. Akt-GSK3β signaling was activated by VO-OHpic administration. IL-10 levels in the medium were elevated by VO-OHpic. CONCLUSION VO-OHpic protects heart tissue by apoptosis resistance via activating Akt-GSK3β signaling and increasing IL-10 levels.
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Affiliation(s)
- Zhang Li
- Department of Cardiology, Huzhou Central Hospital, Huzhou, Zhejiang, China
| | - Zhenfeng Cheng
- Department of Cardiology, Huzhou Central Hospital, Huzhou, Zhejiang, China
| | - Yu Haifeng
- Department of Cardiology, Huzhou Central Hospital, Huzhou, Zhejiang, China
| | - Mengting Chen
- Department of Respiratory Medicine, Huzhou Central Hospital, Huzhou, Zhejiang, China
| | - Lifang Li
- Department of Cardiology, Huzhou Central Hospital, Huzhou, Zhejiang, China.
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10
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Guo J, Zhang S, Ma L, Shi H, Zhu J, Wu J, An Y, Ge J. Cardioprotection by Mild Hypothermia Is Abolished in Aged Mice. Ther Hypothermia Temp Manag 2017; 7:193-198. [PMID: 28445087 DOI: 10.1089/ther.2017.0001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Junjie Guo
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
- Department of Cardiology, The Affiliated Hospital of Qingdao University, Qingdao University, Shandong, China
| | - Shuning Zhang
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Leilei Ma
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hongtao Shi
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jianbing Zhu
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jian Wu
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yi An
- Department of Cardiology, The Affiliated Hospital of Qingdao University, Qingdao University, Shandong, China
| | - Junbo Ge
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
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11
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Inhibition of the mitochondrial fission protein dynamin-related protein 1 improves survival in a murine cardiac arrest model. Crit Care Med 2015; 43:e38-47. [PMID: 25599491 DOI: 10.1097/ccm.0000000000000817] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Survival following sudden cardiac arrest is poor despite advances in cardiopulmonary resuscitation and the use of therapeutic hypothermia. Dynamin-related protein 1, a regulator of mitochondrial fission, is an important determinant of reactive oxygen species generation, myocardial necrosis, and left ventricular function following ischemia/reperfusion injury, but its role in cardiac arrest is unknown. We hypothesized that dynamin-related protein 1 inhibition would improve survival, cardiac hemodynamics, and mitochondrial function in an in vivo model of cardiac arrest. DESIGN Laboratory investigation. SETTING University laboratory. INTERVENTIONS Anesthetized and ventilated adult female C57BL/6 wild-type mice underwent an 8-minute KCl-induced cardiac arrest followed by 90 seconds of cardiopulmonary resuscitation. Mice were then blindly randomized to a single IV injection of Mdivi-1 (0.24 mg/kg), a small molecule dynamin-related protein 1 inhibitor or vehicle (dimethyl sulfoxide). MEASUREMENTS AND MAIN RESULTS Following resuscitation from cardiac arrest, mitochondrial fission was evidenced by dynamin-related protein 1 translocation to the mitochondrial membrane and a decrease in mitochondrial size. Mitochondrial fission was associated with increased lactate and evidence of oxidative damage. Mdivi-1 administration during cardiopulmonary resuscitation inhibited dynamin-related protein 1 activation, preserved mitochondrial morphology, and decreased oxidative damage. Mdivi-1 also reduced the time to return of spontaneous circulation (116 ± 4 vs 143 ± 7 s; p < 0.001) during cardiopulmonary resuscitation and enhanced myocardial performance post-return of spontaneous circulation. These improvements were associated with significant increases in survival (65% vs 33%) and improved neurological scores up to 72 hours post cardiac arrest. CONCLUSIONS Post-cardiac arrest inhibition of dynamin-related protein 1 improves time to return of spontaneous circulation and myocardial hemodynamics, resulting in improved survival and neurological outcomes in a murine model of cardiac arrest. Pharmacological targeting of mitochondrial fission may be a promising therapy for cardiac arrest.
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Li J, Wang H, Zhong Q, Zhu X, Chen SJ, Qian Y, Costakis J, Bunney G, Beiser DG, Leff AR, Lewandowski ED, ÓDonnell JM, Vanden Hoek TL. A novel pharmacological strategy by PTEN inhibition for improving metabolic resuscitation and survival after mouse cardiac arrest. Am J Physiol Heart Circ Physiol 2015; 308:H1414-22. [PMID: 25795713 DOI: 10.1152/ajpheart.00748.2014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 03/17/2015] [Indexed: 01/04/2023]
Abstract
Sudden cardiac arrest (SCA) is a leading cause of death in the United States. Despite return of spontaneous circulation, patients die due to post-SCA syndrome that includes myocardial dysfunction, brain injury, impaired metabolism, and inflammation. No medications improve SCA survival. Our prior work suggests that optimal Akt activation is critical for cooling protection and SCA recovery. Here, we investigate a small inhibitor of PTEN, an Akt-related phosphatase present in heart and brain, as a potential therapy in improving cardiac and neurological recovery after SCA. Anesthetized adult female wild-type C57BL/6 mice were randomized to pretreatment of VO-OHpic (VO) 30 min before SCA or vehicle control. Mice underwent 8 min of KCl-induced asystolic arrest followed by CPR. Resuscitated animals were hemodynamically monitored for 2 h and observed for 72 h. Outcomes included heart pressure-volume loops, energetics (phosphocreatine and ATP from (31)P NMR), protein phosphorylation of Akt, GSK3β, pyruvate dehydrogenase (PDH) and phospholamban, circulating inflammatory cytokines, plasma lactate, and glucose as measures of systemic metabolic recovery. VO reduced deterioration of left ventricular maximum pressure, maximum rate of change in the left ventricular pressure, and Petco2 and improved 72 h neurological intact survival (50% vs. 10%; P < 0.05). It reduced plasma lactate, glucose, IL-1β, and Pre-B cell colony enhancing factor, while increasing IL-10. VO increased phosphorylation of Akt and GSK3β in both heart and brain, and cardiac phospholamban phosphorylation while reducing p-PDH. Moreover, VO improved cardiac bioenergetic recovery. We concluded that pharmacologic PTEN inhibition enhances Akt activation, improving metabolic, cardiovascular, and neurologic recovery with increased survival after SCA. PTEN inhibitors may be a novel pharmacologic strategy for treating SCA.
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Affiliation(s)
- Jing Li
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Huashan Wang
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Qiang Zhong
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois; Department of Emergency Medicine, Tongji Hospital, Tongji Medical College of Huazhong University of Science & Technology, China
| | - Xiangdong Zhu
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Sy-Jou Chen
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois; Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taiwan
| | - Yuanyu Qian
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois; Emergency Department, Chinese PLA General Hospital, Beijing, China
| | - Jim Costakis
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Gabrielle Bunney
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - David G Beiser
- Section of Emergency Medicine, Department of Medicine, University of Chicago, Chicago, Illinois
| | - Alan R Leff
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois; and
| | - E Douglas Lewandowski
- Program in Integrative Cardiac Metabolism, Center for Cardiovascular Research, and Department of Physiology and Biophysics, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - J Michael ÓDonnell
- Program in Integrative Cardiac Metabolism, Center for Cardiovascular Research, and Department of Physiology and Biophysics, University of Illinois Hospital & Health Sciences System, Chicago, Illinois
| | - Terry L Vanden Hoek
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois;
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Lipid emulsion rapidly restores contractility in stunned mouse cardiomyocytes: a comparison with therapeutic hypothermia. Crit Care Med 2015; 42:e734-40. [PMID: 25402294 DOI: 10.1097/ccm.0000000000000656] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVES Cooling following cardiac arrest can improve survival significantly. However, delays in achieving target temperature may decrease the overall benefits of cooling. Here, we test whether lipid emulsion, a clinically approved drug reported to exert cardioprotection, can rescue heart contractility in the setting of delayed cooling in stunned mouse cardiomyocytes. DESIGN Cell culture study. SETTING Academic research laboratory. SUBJECTS Cardiomyocytes isolated from 1- to 2-day-old C57BL6 mice. INTERVENTIONS Cardiomyocytes were exposed to 30 minutes of ischemia followed by 90 minutes of reperfusion and 10 minutes of isoproterenol with nine interventions: 1) no additional treatment; 2) intraischemic cooling at 32 °C initiated 10 minutes prior to reperfusion; 3) delayed cooling started 20 minutes after reperfusion; 4) lipid emulsion + delayed cooling; 5) lipid emulsion (0.25%) administered at reperfusion; 6) lipid emulsion + intraischemic cooling; 7) delayed lipid emulsion; 8) lipid emulsion + delayed cooling + Akt inhibitor (API-2, 10 µM); and 9) lipid emulsion + delayed cooling + Erk inhibitor (U0126, 10 µM). Inhibitors were given to cells 1 hour prior to ischemia. MEASUREMENTS AND MAIN RESULTS Contractility was recorded by real-time phase-contrast imaging and analyzed with pulse image velocimetry in MATLAB (Mathworks, Natick, MA). Ischemia diminished cell contraction. The cardioprotective effect of cooling was diminished when delayed but was rescued by lipid emulsion. Further, lipid emulsion on its own improved recovery of the contractility to a greater extent as intraischemic cooling. However, cotreatment of lipid emulsion and intraischemic cooling did not further improve the recovery compared to either treatment alone. Furthermore, Akt and Erk inhibitors blocked lipid emulsion-induced protection. CONCLUSIONS Lipid emulsion improved contractility and rescued contractility in the context of delayed cooling. This protective effect required Akt and Erk signaling. Lipid emulsion might serve as a treatment or adjunct to cooling in ameliorating myocardial ischemia/reperfusion injury.
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Ning XH, Villet OM, Ge M, Sekhar LN, Corson MA, Tylee TS, Fan LP, Yao L, Zhu C, Olson AK, Buroker NE, Xu CS, Anderson DL, Soh YK, Wang E, Chen SH, Portman MA. Optimal protective hypothermia in arrested mammalian hearts. Ther Hypothermia Temp Manag 2014; 5:40-7. [PMID: 25514569 DOI: 10.1089/ther.2014.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Many therapeutic hypothermia recommendations have been reported, but the information supporting them is sparse, and reveals a need for the data of target therapeutic hypothermia (TTH) from well-controlled experiments. The core temperature ≤35°C is considered as hypothermia, and 29°C is a cooling injury threshold in pig heart in vivo. Thus, an optimal protective hypothermia (OPH) should be in the range 29-35°C. This study was conducted with a pig cardiopulmonary bypass preparation to decrease the core temperature to 29-35°C range at 20 minutes before and 60 minutes during heart arrest. The left ventricular (LV) developed pressure, maximum of the first derivative of LV (dP/dtmax), cardiac power, heart rate, cardiac output, and myocardial velocity (Vmax) were recorded continuously via an LV pressure catheter and an aortic flow probe. At 20 minutes of off-pump during reperfusion after 60 minutes arrest, 17 hypothermic hearts showed that the recovery of Vmax and dP/dtmax established sigmoid curves that consisted of two plateaus: a good recovery plateau at 29-30.5°C, the function recovered to baseline level (BL) (Vmax=118.4%±3.9% of BL, LV dP/dtmax=120.7%±3.1% of BL, n=6); another poor recovery plateau at 34-35°C (Vmax=60.2%±2.8% of BL, LV dP/dtmax=28.0%±5.9% of BL, p<0.05, n=6; ), which are similar to the four normothermia arrest (37°C) hearts (Vmax=55.9%±4.8% of BL, LV dP/dtmax=24.5%±2.1% of BL, n=4). The 32-32.5°C arrest hearts showed moderate recovery (n=5). A point of inflection (around 30.5-31°C) existed at the edge of a good recovery plateau followed by a steep slope. The point presented an OPH that should be the TTH. The results are concordant with data in the mammalian hearts, suggesting that the TTH should be initiated to cool core temperature at 31°C.
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Affiliation(s)
- Xue-Han Ning
- 1 Division of Cardiology, Department of Pediatrics, University of Washington , Seattle, Washington
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Borovnik-Lesjak V, Whitehouse K, Baetiong A, Miao Y, Currie BM, Velmurugan S, Radhakrishnan J, Gazmuri RJ. Effects of intraosseous erythropoietin during hemorrhagic shock in swine. PLoS One 2014; 9:e110908. [PMID: 25365317 PMCID: PMC4218716 DOI: 10.1371/journal.pone.0110908] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 09/21/2014] [Indexed: 11/22/2022] Open
Abstract
Objective To determine whether erythropoietin given during hemorrhagic shock (HS) ameliorates organ injury while improving resuscitation and survival. Methods Three series of 24 pigs each were studied. In an initial series, 50% of the blood volume (BV) was removed in 30 minutes and normal saline (threefold the blood removed) started at minute 90 infusing each third in 30, 60, and 150 minutes with shed blood reinfused at minute 330 (HS-50BV). In a second series, the same HS-50BV protocol was used but removing an additional 15% of BV from minute 30 to 60 (HS-65BV). In a final series, blood was removed as in HS-65BV and intraosseous vasopressin given from minute 30 (0.04 U/kg min−1) until start of shed blood reinfusion at minute 150 (HS-65BV+VP). Normal saline was reduced to half the blood removed and given from minute 90 to 120 in half of the animals. In each series, animals were randomized 1∶1 to receive erythropoietin (1,200 U/kg) or control solution intraosseously after removing 10% of the BV. Results In HS-50BV, O2 consumption remained near baseline yielding minimal lactate increases, 88% resuscitability, and 60% survival at 72 hours. In HS-65BV, O2 consumption was reduced and lactate increased yielding 25% resuscitability. In HS-65BV+VP, vasopressin promoted hemodynamic stability yielding 92% resuscitability and 83% survival at 72 hours. Erythropoietin did not affect resuscitability or subsequent survival in any of the series but increased interleukin-10, attenuated lactate increases, and ameliorated organ injury based on lesser troponin I, AST, and ALT increases and lesser neurological deficits in the HS-65BV+VP series. Conclusions Erythropoietin given during HS in swine failed to alter resuscitability and 72 hour survival regardless of HS severity and concomitant treatment with fluids and vasopressin but attenuated acute organ injury. The studies also showed the efficacy of vasopressin and restrictive fluid resuscitation for hemodynamic stabilization and survival.
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Affiliation(s)
- Vesna Borovnik-Lesjak
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Kasen Whitehouse
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Alvin Baetiong
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Yang Miao
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Brian M. Currie
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Sathya Velmurugan
- Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Jeejabai Radhakrishnan
- Department of Medicine and Resuscitation Institute at Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Raúl J. Gazmuri
- Department of Medicine, Department of Physiology and Biophysics, and Resuscitation Institute at Rosalind Franklin University of Medicine and Science, and Critical Care Medicine at the Captain James A. Lovell Federal Health Care Center, North Chicago, Illinois, United States of America
- * E-mail:
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Beneficial effects of nitric oxide on outcomes after cardiac arrest and cardiopulmonary resuscitation in hypothermia-treated mice. Anesthesiology 2014; 120:880-9. [PMID: 24496125 DOI: 10.1097/aln.0000000000000149] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Therapeutic hypothermia (TH) improves neurological outcomes after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). Although nitric oxide prevents organ injury induced by ischemia and reperfusion, role of nitric oxide during TH after CPR remains unclear. In this article, the authors examined the impact of endogenous nitric oxide synthesis on the beneficial effects of hypothermia after CA/CPR. The authors also examined whether or not inhaled nitric oxide during hypothermia further improves outcomes after CA/CPR in mice treated with TH. METHODS Wild-type mice and mice deficient for nitric oxide synthase 3 (NOS3(−/−)) were subjected to CA at 37 °C and then resuscitated with chest compression. Body temperature was maintained at 37 °C (normothermia) or reduced to 33 °C (TH) for 24 h after resuscitation. Mice breathed air or air mixed with nitric oxide at 10, 20, 40, 60, or 80 ppm during hypothermia. To evaluate brain injury and cerebral blood flow, magnetic resonance imaging was performed in wild-type mice after CA/CPR. RESULTS Hypothermia up-regulated the NOS3-dependent signaling in the brain (n = 6 to 7). Deficiency of NOS3 abolished the beneficial effects of hypothermia after CA/CPR (n = 5 to 6). Breathing nitric oxide at 40 ppm improved survival rate in hypothermia-treated NOS3(−/−) mice (n = 6) after CA/CPR compared with NOS3(−/−) mice that were treated with hypothermia alone (n = 6; P < 0.05). Breathing nitric oxide at 40 (n = 9) or 60 (n = 9) ppm markedly improved survival rates in TH-treated wild-type mice (n = 51) (both P < 0.05 vs. TH-treated wild-type mice). Inhaled nitric oxide during TH (n = 7) prevented brain injury compared with TH alone (n = 7) without affecting cerebral blood flow after CA/CPR (n = 6). CONCLUSIONS NOS3 is required for the beneficial effects of TH. Inhaled nitric oxide during TH remains beneficial and further improves outcomes after CA/CPR. Nitric oxide breathing exerts protective effects after CA/CPR even when TH is ineffective due to impaired endogenous nitric oxide production.
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Zhu X, Shao ZH, Li C, Li J, Zhong Q, Learoyd J, Meliton A, Meliton L, Leff AR, Vanden Hoek TL. TAT-protein blockade during ischemia/reperfusion reveals critical role for p85 PI3K-PTEN interaction in cardiomyocyte injury. PLoS One 2014; 9:e95622. [PMID: 24752319 PMCID: PMC3994094 DOI: 10.1371/journal.pone.0095622] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/27/2014] [Indexed: 11/19/2022] Open
Abstract
Recent work shows that cooling protection after mouse cardiac arrest and cardiomyocyte ischemia is mediated by Akt activation. The PI3K p85 subunit can either augment or inhibit Akt activation depending on its binding to p110 or PTEN respectively. To further clarify the role of PI3K p85 in cardioprotection, we studied novel TAT-p85 fusion proteins that selectively inhibit PI3K p85 binding. We hypothesized that TAT fused p85 lacking the PTEN binding site (TAT-ΔPTEN p85) would enhance Akt phosphorylation to afford cardioprotection. Conversely, TAT fused p85 lacking the p110 binding site (TAT-Δp110p85) would decrease Akt phosphorylation and abrogate cardioprotection. Microscopy and Western blot analysis demonstrated that TAT fusion protein was transduced into cardiomyocytes within 5 min and remained more than 2 h. Inhibition of PI3K/Akt by TAT-Δp110 p85 significantly increased cell death from 44.6±2.7% to 92.5±3.4% after simulated ischemia and reperfusion. By contrast, PTEN inhibition using TAT-ΔPTEN p85 decreased cell death to 11.9±5.3%, a similar level of cardioprotection seen with past cooling studies. Additional studies with the small molecule PTEN inhibitor VO-OHpic confirmed that PTEN inhibition was highly protective against cell death induced by ischemia and reperfusion. We conclude that blockade of p85-PTEN interaction and PTEN inhibition may be promising strategies for rescuing the heart from ischemia and reperfusion injury.
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Affiliation(s)
- Xiangdong Zhu
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
| | - Zuo-Hui Shao
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
| | - Changqing Li
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
| | - Jing Li
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
| | - Qiang Zhong
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
| | - Jonathan Learoyd
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Angelo Meliton
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Lucille Meliton
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Alan R. Leff
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Terry L. Vanden Hoek
- Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America
- * E-mail:
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Jackson TC, Verrier JD, Drabek T, Janesko-Feldman K, Gillespie DG, Uray T, Dezfulian C, Clark RS, Bayir H, Jackson EK, Kochanek PM. Pharmacological inhibition of pleckstrin homology domain leucine-rich repeat protein phosphatase is neuroprotective: differential effects on astrocytes. J Pharmacol Exp Ther 2013; 347:516-28. [PMID: 24023368 DOI: 10.1124/jpet.113.206888] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pleckstrin homology domain and leucine-rich repeat protein phosphatase 1 (PHLPP1) inhibits protein kinase B (AKT) survival signaling in neurons. Small molecule pan-PHLPP inhibitors (selective for PHLPP1 and PHLPP2) may offer a translatable method to induce AKT neuroprotection. We tested several recently discovered PHLPP inhibitors (NSC117079 and NSC45586; benzoic acid, 5-[2-[4-[2-(2,4-diamino-5-methylphenyl)diazenyl]phenyl]diazenyl]-2-hydroxy-,sodium salt.) in rat cortical neurons and astrocytes and compared the biochemical response of these agents with short hairpin RNA (shRNA)-mediated PHLPP1 knockdown (KD). In neurons, both PHLPP1 KD and experimental PHLPP inhibitors activated AKT and ameliorated staurosporine (STS)-induced cell death. Unexpectedly, in astrocytes, both inhibitors blocked AKT activation, and NSC117079 reduced viability. Only PHLPP2 KD mimicked PHLPP inhibitors on astrocyte biochemistry. This suggests that these inhibitors could have possible detrimental effects on astrocytes by blocking novel PHLPP2-mediated prosurvival signaling mechanisms. Finally, because PHLPP1 levels are reportedly high in the hippocampus (a region prone to ischemic death), we characterized hippocampal changes in PHLPP and several AKT targeting prodeath phosphatases after cardiac arrest (CA)-induced brain injury. PHLPP1 levels increased in rat brains subjected to CA. None of the other AKT inhibitory phosphatases increased after global ischemia (i.e., PHLPP2, PTEN, PP2A, and PP1). Selective PHLPP1 inhibition (such as by shRNA KD) activates AKT survival signaling in neurons and astrocytes. Nonspecific PHLPP inhibition (by NSC117079 and NSC45586) only activates AKT in neurons. Taken together, these results suggest that selective PHLPP1 inhibitors should be developed and may yield optimal strategies to protect injured hippocampal neurons and astrocytes-namely from global brain ischemia.
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Affiliation(s)
- Travis C Jackson
- University of Pittsburgh School of Medicine, Department of Critical Care Medicine, Safar Center for Resuscitation Research (T.C.J., P.M.K., H.B., R.S.C, K.J.F., C.D., T.U.) and Department of Pharmacology and Chemical Biology (J.D.V., D.G.G., E.K.J.),University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and Department of Anesthesiology, Presbyterian Hospital (T.D.), Pittsburgh, Pennsylvania
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Gorshkova IA, Wang H, Orbelyan GA, Goya J, Natarajan V, Beiser DG, Vanden Hoek TL, Berdyshev EV. Inhibition of sphingosine-1-phosphate lyase rescues sphingosine kinase-1-knockout phenotype following murine cardiac arrest. Life Sci 2013; 93:359-66. [PMID: 23892195 DOI: 10.1016/j.lfs.2013.07.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 06/09/2013] [Accepted: 07/12/2013] [Indexed: 01/24/2023]
Abstract
AIMS To test the role of sphingosine-1-phosphate (S1P) signaling system in the in vivo setting of resuscitation and survival after cardiac arrest. MAIN METHODS A mouse model of potassium-induced cardiac arrest and resuscitation was used to test the importance of S1P homeostasis in resuscitation and survival. C57BL/6 and sphingosine kinase-1 knockout (SphK1-KO) female mice were arrested for 8 min then subjected to 5 minute CPR with epinephrine bolus given at 90s after the beginning of CPR. Animal survival was monitored for 4h post-resuscitation. Upregulation of tissue and circulatory S1P levels were achieved via inhibition of S1P lyase by 2-acetyl-5-tetrahydroxybutyl imidazole (THI). Plasma and heart tissue S1P and ceramide levels were quantified by targeted ESI-LC/MS/MS. KEY FINDINGS Lack of SphK1 and low tissue/circulatory S1P levels in SphK1-KO mice led to poor animal resuscitation after cardiac arrest and to impaired survival post-resuscitation. Inhibition of S1P lyase in SphK1-KO mice drastically improved animal resuscitation and survival. Improved resuscitation and survival of THI-treated SphK1-KO mice were better correlated with cardiac dihydro-S1P (DHS1P) than S1P levels. The lack of SphK1 and the inhibition of S1P lyase by THI were accompanied by modulation in cardiac S1PR1 and S1PR2 expression and by selective changes in plasma N-palmitoyl- and N-behenoyl-ceramide levels. SIGNIFICANCE Our data provide evidence for the crucial role for SphK1 and S1P signaling system in resuscitation and survival after cardiac arrest, which may form the basis for development of novel therapeutic strategy to support resuscitation and long-term survival of cardiac arrest patients.
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Affiliation(s)
- Irina A Gorshkova
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
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Sköld K, Alm H, Scholz B. The impact of biosampling procedures on molecular data interpretation. Mol Cell Proteomics 2013; 12:1489-501. [PMID: 23382104 PMCID: PMC3675808 DOI: 10.1074/mcp.r112.024869] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 01/17/2013] [Indexed: 01/06/2023] Open
Abstract
The separation between biological and technical variation without extensive use of technical replicates is often challenging, particularly in the context of different forms of protein and peptide modifications. Biosampling procedures in the research laboratory are easier to conduct within a shorter time frame and under controlled conditions as compared with clinical sampling, with the latter often having issues of reproducibility. But is the research laboratory biosampling really less variable? Biosampling introduces within minutes rapid tissue-specific changes in the cellular microenvironment, thus inducing a range of different pathways associated with cell survival. Biosampling involves hypoxia and, depending on the circumstances, hypothermia, circumstances for which there are evolutionarily conserved defense strategies in the range of species and also are relevant for the range of biomedical conditions. It remains unclear to what extent such adaptive processes are reflected in different biosampling procedures or how important they are for the definition of sample quality. Lately, an increasing number of comparative studies on different biosampling approaches, post-mortem effects and pre-sampling biological state, have investigated such immediate early biosampling effects. Commonalities between biosampling effects and a range of ischemia/reperfusion- and hypometabolism/anoxia-associated biological phenomena indicate that even small variations in post-sampling time intervals are likely to introduce a set of nonrandom and tissue-specific effects of experimental importance (both in vivo and in vitro). This review integrates the information provided by these comparative studies and discusses how an adaptive biological perspective in biosampling procedures may be relevant for sample quality issues.
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Affiliation(s)
- Karl Sköld
- From ‡Denator AB, Uppsala Science Park, SE-75183 Uppsala and
| | - Henrik Alm
- the §Department of Pharmaceutical Biosciences, Division of Drug Safety and Toxicology, Uppsala University, SE-75124 Uppsala, Sweden
| | - Birger Scholz
- the §Department of Pharmaceutical Biosciences, Division of Drug Safety and Toxicology, Uppsala University, SE-75124 Uppsala, Sweden
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Oda T, Shimizu K, Yamaguchi A, Satoh K, Matsumoto KI. Hypothermia produces rat liver proteomic changes as in hibernating mammals but decreases endoplasmic reticulum chaperones. Cryobiology 2012; 65:104-12. [DOI: 10.1016/j.cryobiol.2012.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 04/24/2012] [Accepted: 05/10/2012] [Indexed: 12/25/2022]
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Dae MW. Hypothermia and percutaneous coronary intervention during acute myocardial infarction. Interv Cardiol 2012. [DOI: 10.2217/ica.12.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Therapeutic hypothermia cardioprotection in murine hemorrhagic shock/resuscitation differentially affects p38α/p38γ, Akt, and HspB1. ACTA ACUST UNITED AC 2011; 71:1262-70. [PMID: 22071928 DOI: 10.1097/ta.0b013e31821280c5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Therapeutic hypothermia (TH) has demonstrated great potential for forestalling cardiovascular collapse and improving outcomes in the setting of severe hemorrhagic shock (HS). We used an established mouse model of severe HS to study the response of interrelated cardiac-signaling proteins p38, HspB1, and Akt to shock, resuscitation, and cardioprotective TH. METHODS Adult female C57BL6/J mice were bled and maintained at a mean arterial pressure of 35 mm Hg. After 30 minutes, mice were randomized to 120 minutes of TH (33°C ± 0.5°C) or continued normothermia at 37°C. After 90 minutes, animals were resuscitated and monitored for 180 minutes. Cardiac p38, Akt, and HspB1 phosphorylation (p-p38, p-Akt, and p-HspB1), expression, and Akt/HspB1 interactions were measured at serial time points during HS and resuscitation. Markers of mitochondrial damage (plasma cytochrome c), inflammation (myeloperoxidase), and apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling) were analyzed. RESULTS By 15 minutes HS, p-p38 and p-HspB1 significantly increased while p-Akt(T308) decreased (p < 0.05). TH attenuated phosphorylation of the p38α isoform during HS and increased phosphorylation of the p38γ isoform during both HS and early resuscitation (p < 0.05). TH increased Akt/HspB1 coimmunoprecipitation during early resuscitation and increased p-Akt and HspB1 expression during late resuscitation (p < 0.05). Finally, TH attenuated the myocardial myeloperoxidase and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling staining and plasma cytochrome c during late resuscitation. CONCLUSIONS TH increases phosphorylation of p38γ during both HS and early resuscitation, but attenuates phosphorylation of p38α, increases Akt/HspB1 interaction, and modulates Akt phosphorylation during HS and resuscitation. Such TH-related signaling events are associated with reduced cardiac inflammation, apoptosis, and mitochondrial injury.
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Beiser DG, Orbelyan GA, Inouye BT, Costakis JG, Hamann KJ, McNally EM, Vanden Hoek TL. Genetic deletion of NOS3 increases lethal cardiac dysfunction following mouse cardiac arrest. Resuscitation 2010; 82:115-21. [PMID: 20951489 DOI: 10.1016/j.resuscitation.2010.08.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 08/23/2010] [Accepted: 08/30/2010] [Indexed: 12/23/2022]
Abstract
STUDY AIMS Cardiac arrest mortality is significantly affected by failure to obtain return of spontaneous circulation (ROSC) despite cardiopulmonary resuscitation (CPR). Severe myocardial dysfunction and cardiovascular collapse further affects mortality within hours of initial ROSC. Recent work suggests that enhancement of nitric oxide (NO) signaling within minutes of CPR can improve myocardial function and survival. We studied the role of NO signaling on cardiovascular outcomes following cardiac arrest and resuscitation using endothelial NO synthase knockout (NOS3(-/-)) mice. METHODS Adult female wild-type (WT) and NOS3(-/-) mice were anesthetized, intubated, and instrumented with left-ventricular pressure-volume catheters. Cardiac arrest was induced with intravenous potassium chloride. CPR was performed after 8min of untreated arrest. ROSC rate, cardiac function, whole-blood nitrosylhemoglobin (HbNO) concentrations, heart NOS3 content and phosphorylation (p-NOS3), cyclic guanosine monophosphate (cGMP), and phospho-troponin I (p-TnI) were measured. RESULTS Despite equal quality CPR, NOS3(-/-) mice displayed lower rates of ROSC compared to WT (47.6% [10/21] vs. 82.4% [14/17], p<0.005). Among ROSC animals, NOS3(-/-) vs. WT mice exhibited increased left-ventricular dysfunction and 120min mortality. Prior to ROSC, myocardial effectors of NO signaling including cGMP and p-TnI were decreased in NOS3(-/-) vs. WT mice (p<0.05). Following ROSC in WT mice, significant NOS3-dependent increases in circulating HbNO were seen by 120min. Significant increases in cardiac p-NOS3 occurred between end-arrest and 15min post-ROSC, while total NOS3 content was increased by 120min post-ROSC (p<0.05). CONCLUSIONS Genetic deletion of NOS3 decreases ROSC rate and worsens post-ROSC left-ventricular function. Poor cardiovascular outcomes are associated with differences in NOS3-dependent myocardial cGMP signaling and circulating NO metabolites.
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Affiliation(s)
- David G Beiser
- Emergency Resuscitation Center, Section of Emergency Medicine, University of Chicago, 5841 S. Maryland Ave., MC 5068, Chicago, IL 60637, USA.
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Shao ZH, Sharp WW, Wojcik KR, Li CQ, Han M, Chang WT, Ramachandran S, Li J, Hamann KJ, Vanden Hoek TL. Therapeutic hypothermia cardioprotection via Akt- and nitric oxide-mediated attenuation of mitochondrial oxidants. Am J Physiol Heart Circ Physiol 2010; 298:H2164-73. [PMID: 20382860 DOI: 10.1152/ajpheart.00994.2009] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Therapeutic hypothermia (TH) is a promising cardioprotective treatment for cardiac arrest and acute myocardial infarction, but its cytoprotective mechanisms remain unknown. In this study, we developed a murine cardiomyocyte model of ischemia-reperfusion injury to better determine the mechanisms of TH cardioprotection. We hypothesized that TH manipulates Akt, a survival kinase that mediates mitochondrial protection by modulating reactive oxygen species (ROS) and nitric oxide (NO) generation. Cardiomyocytes, isolated from 1- to 2-day-old C57BL6/J mice, were exposed to 90 min simulated ischemia and 3 h reperfusion. For TH, cells were cooled to 32 degrees C during the last 20 min of ischemia and the first hour of reperfusion. Cell viability was evaluated by propidium iodide and lactate dehydrogenase release. ROS production was measured by 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate and mitochondrial membrane potential (DeltaPsim) by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazoly-carbocyanine iodide (JC-1). Phospho (p)-Akt (Thr308), p-Akt (Ser473), and phosphorylated heat shock protein 27 (p-HSP27) (Ser82) were analyzed by Western blot analysis. TH attenuated reperfusion ROS generation, increased NO, maintained DeltaPsim, and decreased cell death [19.3 + or - 3.3% (n = 11) vs. 44.7 + or - 2.7% (n = 10), P < 0.001]. TH also increased p-Akt during ischemia before reperfusion. TH protection and attenuation of ROS were blocked by the inhibition of Akt and NO synthase but not by a cGMP inhibitor. HSP27, a regulator of Akt, also exhibited increased phosphorylation (Ser82) during ischemia with TH. We conclude that TH cardioprotection is mediated by enhanced Akt/HSP27 phosphorylation and enhanced NO generation, resulting in the attenuation of ROS generation and the maintenance of DeltaPsim following ischemia-reperfusion.
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Affiliation(s)
- Zuo-Hui Shao
- Section of Emergency Medicine, Department of Medicine, Emergency Resuscitation Center, University of Chicago, Chicago, IL, USA
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