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Maslov LN, Naryzhnaya NV, Sirotina M, Mukhomedzyanov AV, Kurbatov BK, Boshchenko AA, Ma H, Zhang Y, Fu F, Pei J, Azev VN, Pereverzev VA. Do reactive oxygen species damage or protect the heart in ischemia and reperfusion? Analysis on experimental and clinical data. J Biomed Res 2023; 37:268-280. [PMID: 37503710 PMCID: PMC10387750 DOI: 10.7555/jbr.36.20220261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
The role of reactive oxygen species (ROS) in ischemic and reperfusion (I/R) injury of the heart has been discussed for more than 40 years. It has been demonstrated that reperfusion triggers a multiple increase in free radical generation in the isolated heart. Antioxidants were found to have the ability to mitigate I/R injury of the heart. However, it is unclear whether their cardioprotective effect truly depends on the decrease of ROS levels in myocardial tissues. Since high doses and high concentrations of antioxidants were experimentally used, it is highly likely that the cardioprotective effect of antioxidants depends on their interaction not only with free radicals but also with other molecules. It has been demonstrated that the antioxidant N-2-mercaptopropionyl glycine or NDPH oxidase knockout abolished the cardioprotective effect of ischemic preconditioning. Consequently, there is evidence that ROS protect the heart against the I/R injury.
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Affiliation(s)
- Leonid N Maslov
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Natalia V Naryzhnaya
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Maria Sirotina
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Alexandr V Mukhomedzyanov
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Boris K Kurbatov
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Alla A Boshchenko
- Cardiology Research Institute, Tomsk National Research Medical Center, the Russian Academy of Sciences, Tomsk, Tomsk Region 634012, Russia
| | - Huijie Ma
- Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Yi Zhang
- Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Feng Fu
- Department of Physiology and Pathophysiology, National Key Discipline of Cell Biology, School of Basic Medicine, the Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Jianming Pei
- Department of Physiology and Pathophysiology, National Key Discipline of Cell Biology, School of Basic Medicine, the Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Viacheslav N Azev
- The Branch of the Institute of Bioorganic Chemistry, Russian Academy of Sciences, Pushchino, Moscow Oblast 142290, Russia
| | - Vladimir A Pereverzev
- Department of Normal Physiology, Belarusian State Medical University, Minsk 220083, Belarus
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Xiao M, Zeng W, Wang J, Yao F, Peng Z, Liu G, Yu L, Wei W, Zhou S, Li K, Wu L, Zhu K, Guan Y, Chen H, Liu Z, Chen J. Exosomes Protect Against Acute Myocardial Infarction in Rats by Regulating the Renin-Angiotensin System. Stem Cells Dev 2021; 30:622-631. [PMID: 33765842 DOI: 10.1089/scd.2020.0132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The renin-angiotensin system (RAS) has been suggested to play an important role in cardiac remodeling after acute myocardial infarction (AMI). We have confirmed that bone marrow mesenchymal stem cell-derived exosomes (BMSC-EX) had similar types of repair like effects upon tissues as BMSC, but the mechanisms remain unknown. BMSC were cultured to the third generation and were induced to release exosomes. Rats were injected with exosomes (100 μg/mL) or stem cells (1 × 106/mL) through the tail vein immediately after AMI was built, compared to those treated with physiological saline. Thereafter, all groups were analyzed for cardiac function, infarction sizes, and the levels of expression of BNP, ACE, ACE2, AngII, Ang1-7, and other factors in the plasma. After H2O2 makes contact with H9C2 cardiomyocytes, cell proliferation activity and apoptotic rates were measured by using CCK8 kits, to facilitate investigation of the effect of exosomes on H9C2 cells. In vivo, the index of cardiac remodeling and cardiac function was improved in both groups of exosomes and stem cells after AMI. Furthermore, exosomes may have helped to regulate the balance of the RAS system, upregulate ACE2-Ang1-7-Mas, and downregulate the ACE-AngII-ATIR pathway. Therefore, its effects were such as to accelerate the conversion of Ang II to Ang 1-7, thereby improving cardiac remodeling and forming sustained myocardial protection. In vitro, exosomal intervention was found to have increased the levels of activity of H9C2 cardiomyocytes under H2O2 injury and improved adverse effects of AngII upon H9C2 cells. All procedures for this study were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) at Guangdong Medical University. BMSC-EX improved cardiac remodeling and cardiac function, and had effects upon RAS system-related factors in plasma. Similarly, BMSC-EX also helped to protect H9C2 cells under attack from H2O2 or AngII, and may thus play beneficial roles by facilitating regulation of the balance of the RAS system.
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Affiliation(s)
- Mengyuan Xiao
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Weikai Zeng
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Junxian Wang
- Gerontology Center, Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Feng Yao
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Zijian Peng
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Guangyan Liu
- Gerontology Center, Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Liqin Yu
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Wenyan Wei
- Gerontology Center, Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Shengzhi Zhou
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Kaize Li
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Luyao Wu
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Kunpeng Zhu
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Yuejie Guan
- Gerontology Center, Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Huanyu Chen
- The Second Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhenjun Liu
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
| | - Jianying Chen
- Cardiovascular Medicine Center and Affiliated Hospital of Guangdong Medical University, Zhangjiang, China
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Raut GK, Manchineela S, Chakrabarti M, Bhukya CK, Naini R, Venkateshwari A, Reddy VD, Mendonza JJ, Suresh Y, Nallari P, Bhadra MP. Imine stilbene analog ameliorate isoproterenol-induced cardiac hypertrophy and hydrogen peroxide-induced apoptosis. Free Radic Biol Med 2020; 153:80-88. [PMID: 32311492 DOI: 10.1016/j.freeradbiomed.2020.04.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 12/20/2022]
Abstract
Cardiac hypertrophy is an adaptive response to stress, in order to maintain proper cardiac function. However, sustained stress leads to pathological hypertrophy accompanied by maladaptive responses and ultimately heart failure. At the cellular level, cardiomyocyte hypertrophy is characterized by an increase in myocyte size, reactivation of the fetal gene markers, disassembly of the sarcomere and transcriptional remodelling which are regulated by heart-specific transcription factors like MEF2, GATA4 and immediate early genes like c-jun and c-fos.2. It has been explored and established that the hypertrophic process is associated by oxidative stress and mediated by pathways involving several terminal stress kinases like P38, JNK and ERK1/2. Stilbenoids are bioactive polyphenols and earlier studies have shown that imine stilbene exert cardioprotective and anti aging effects by acting as modulators of Sirt1. The present study was aimed at designing and synthesizing a series of imine stilbene analogs and investigate its anti hypertrophic effects and regulatory mechanism in cardiac hypertrophy and apoptosis. Interestingly one of the analog, compound 3e (10 μM) alleviated isoproterenol (ISO, 25 μM) induced hypertrophy in rat cardiomyocyte (H9c2) cells by showing a marked decrease in the myocyte size. Further, compound 3e also restored the cardiac function by activating the metabolic stress sensor, AMPK. Moreover, molecular docking studies showed stable binding between compound 3e and GSK3β suggesting that compound 3e may directly regulate GSK3β activity and ameliorate ISO-induced cardiac hypertrophy. In agreement with this, compound 3e also modulated the crosstalk of all the hypertrophy inducing terminal Kinases by bringing down the expression to near control conditions. The compound also relieved H2O2 (100 μM) mediated ROS and normalized abnormal mitochondrial oxygen demand in hypertrophic conditions indicating the possibility of the compound to show promise in playing a role in cardiac hypertrophy.
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Affiliation(s)
- Ganesh Kumar Raut
- Applied Biology Department, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai, 600113, India
| | - Sairam Manchineela
- Department of Genetics, Osmania University, Amberpet, Hyderabad, 500007, Telangana State, India
| | - Moumita Chakrabarti
- Applied Biology Department, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai, 600113, India
| | - Chaitanya Kumar Bhukya
- Department of Genetics, Osmania University, Amberpet, Hyderabad, 500007, Telangana State, India
| | - Raju Naini
- Center for Plant Molecular Biology, Osmania University, Amberpet, Hyderabad, 500007, Telangana State, India
| | - A Venkateshwari
- Institute of Genetics & Hospital for Genetics Disease, Osmania University, Ameerpet, Hyderabad, 500007, Telangana State, India
| | - V D Reddy
- Center for Plant Molecular Biology, Osmania University, Amberpet, Hyderabad, 500007, Telangana State, India
| | - Jolly Janette Mendonza
- Applied Biology Department, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai, 600113, India
| | - Y Suresh
- Applied Biology Department, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad, 500007, Telangana State, India
| | - Pratibha Nallari
- Department of Genetics, Osmania University, Amberpet, Hyderabad, 500007, Telangana State, India
| | - Manika Pal Bhadra
- Applied Biology Department, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai, 600113, India.
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Wu L, Tan JL, Chen ZY, Huang G. Cardioprotection of post-ischemic moderate ROS against ischemia/reperfusion via STAT3-induced the inhibition of MCU opening. Basic Res Cardiol 2019; 114:39. [DOI: 10.1007/s00395-019-0747-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022]
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Effects of Four Compounds from Gentianella acuta (Michx.) Hulten on Hydrogen Peroxide-Induced Injury in H9c2 Cells. BIOMED RESEARCH INTERNATIONAL 2019; 2019:2692970. [PMID: 30800665 PMCID: PMC6360564 DOI: 10.1155/2019/2692970] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 12/03/2022]
Abstract
In previous studies, Gentianella acuta (Michx.) Hulten was reported to contain xanthones, iridoids, terpenoids, and sterols and is mainly used to cure hepatitis, jaundice, fever, headache, and angina pectoris. In this study, we used bioassay guided fractionation to identify compounds from G. acuta and investigated their activity against hydrogen peroxide (H2O2)-induced apoptosis of H9c2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic (GCLC) expression were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was evaluated using western blot. The results showed that all four compounds had protective effects on H9c2 cells. The transcription levels of HO-1 and GCLC significantly increased in H9c2 cells pretreated with norswertianolin (1), swetrianolin (2), demethylbellidifolin (3), and bellidifolin (4). However, compared to the model group, the transcription levels of Nrf2 were not enhanced by pretreatment with compounds 1, 2, and 4. The protein expression levels of HO-1 and GCLC in H9c2 cells were greater than that in the H2O2-treated group, and the expression of Nrf2 was not significantly changed except by swetrianolin treatment; inhibitors can reverse the protective effect by ZnPP (15 μM), BSO (10 μM), and brusatol (10 μM). The results indicated that the four compounds isolated from G. acuta inhibited the oxidative injury induced by H2O2 by activating the Nrf2/ARE pathway in H9c2 cells and provide evidence that G. acuta may be a potential therapeutic agent for the treatment of cardiovascular diseases.
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Chen S, Dong C, Zhang J, Tang B, Xi Z, Cai F, Gong Y, Xu J, Qi L, Wang Q, Chen J. Human menstrual blood-derived stem cells protect H9c2 cells against hydrogen peroxide-associated apoptosis. In Vitro Cell Dev Biol Anim 2019; 55:104-112. [PMID: 30617572 DOI: 10.1007/s11626-018-0311-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 11/09/2018] [Indexed: 01/03/2023]
Abstract
Human menstrual blood-derived mesenchymal stem cells (MenSCs) hold great promise for regenerative medicine. Here, H2O2-associated damage in H9c2 cells was employed as an in vitro ischemia-reperfusion model, and the transwell system was used to explore the beneficial effects of MenSCs on the H2O2-induced damage of myocardial H9c2 cells. H2O2 treatment resulted in decreased viability and migration rate, with increased apoptosis levels in cells. By contrast, upon co-culture with MenSCs, H9c2 cell viability and migration were increased, whereas the apoptotic rate decreased. Additionally, western blot and qRT-PCR showed that MenSCs mediated the anti-apoptotic role by downregulating the pro-apoptotic genes Bax and caspase-3, while upregulating the anti-apoptotic effector Bcl-2. Furthermore, co-culture with MenSCs resulted in elevated expression of N-cadherin after H2O2 treatment. These findings indicate that MenSCs protect H9c2 cells against H2O2-associated programmed cell death and would help develop therapeutic tools for cardiomyocyte apoptosis associated with oxidative stress.
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Affiliation(s)
- Song Chen
- Department of Cardiology, Nantong Maternal and Child Health Care Hospital, No. 399 Century Avenue, Nantong, 226001, Jiangsu, China
| | - Chuanming Dong
- Department of Anatomy, Medical School of Nantong University, Laboratory Animal Center of Nantong University, Nantong, 226001, Jiangsu, China
| | - Jinyun Zhang
- Department of Cardiology, Nantong Maternal and Child Health Care Hospital, No. 399 Century Avenue, Nantong, 226001, Jiangsu, China
| | - Baohua Tang
- Department of Cardiology, Nantong Maternal and Child Health Care Hospital, No. 399 Century Avenue, Nantong, 226001, Jiangsu, China
| | - Zhengrong Xi
- Department of Emergency, Nantong Maternal and Child Health Care Hospital, Nantong, Jiangsu, China
| | - Fei Cai
- Department of Cardiology, Nantong Third People's Hospital, Nantong, Jiangsu, China
| | - Yachi Gong
- Department of Geriatric Medicine, Nantong Third People's Hospital, Nantong, Jiangsu, China
| | - Jianru Xu
- Department of Emergency, Nantong Third People's Hospital, Nantong, Jiangsu, China
| | - Longju Qi
- Department of Interventional Therapy, Nantong Third People's Hospital, Nantong, Jiangsu, China
| | - Qinghua Wang
- Department of Anatomy, Medical School of Nantong University, Laboratory Animal Center of Nantong University, Nantong, 226001, Jiangsu, China.
| | - Jian Chen
- Department of Cardiology, Nantong Maternal and Child Health Care Hospital, No. 399 Century Avenue, Nantong, 226001, Jiangsu, China.
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Wang Z, Cui R, Wang K. Effects of sevoflurane pretreatment on the apoptosis of rat H9c2 cardiomyocytes and the expression of GRP78. Exp Ther Med 2018; 15:2818-2823. [PMID: 29599827 PMCID: PMC5867468 DOI: 10.3892/etm.2018.5799] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/02/2018] [Indexed: 01/28/2023] Open
Abstract
The protective effect of sevoflurane on apoptosis of rat H9c2 cardiomyocytes induced by H2O2 and the effect on the expression of glucose-regulated protein 78 (GRP78) were investigated. H9c2 cells were routinely cultured and divided into the control, model and sevoflurane groups. Cells in the model group were treated with 400 µM H2O2, and cells in the sevoflurane group were pretreated with sevoflurane prior to treatment with 400 µM H2O2. MTT assay was used to assess cell viability. Annexin V-propidium iodide (AV-PI) double staining flow cytometry was used to detect apoptosis. The intracellular free Ca2+ concentration was measured by the fluorescence-based assay using Fluo-3 AM as a calcium ion fluorescence probe. The mRNA expression level of GRP78 and protein expression levels of GRP78, CHOP and caspase-12 were measured using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. The assays showed that after sevoflurane pretreatment the H9c2 cell viability was significantly increased, whereas the H2O2-induced apoptosis, intracellular Ca2+ concentration, mRNA expression of GRP78, and the protein expression of GRP78, CHOP and caspase-12 were all reduced. The results show that pretreatment with sevoflurane inhibited H2O2-induced apoptosis in H9c2 cells. The mechanism may be related to inhibition of the stress-related protein GRP78 expression in endoplasmic reticulum, resulting in decreased intracellular Ca2+ concentration and the downregulation of CHOP and caspase-12 expression levels.
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Affiliation(s)
- Zhongli Wang
- Department of Anesthesiology, People's Hospital of Rizhao, Rizhao, Shandong 276800, P.R. China
| | - Rongsheng Cui
- Department of Anesthesiology, People's Hospital of Rizhao, Rizhao, Shandong 276800, P.R. China
| | - Kai Wang
- Department of Anesthesiology, People's Hospital of Rizhao, Rizhao, Shandong 276800, P.R. China
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Wu L, Tan JL, Wang ZH, Chen YX, Gao L, Liu JL, Shi YH, Endoh M, Yang HT. ROS generated during early reperfusion contribute to intermittent hypobaric hypoxia-afforded cardioprotection against postischemia-induced Ca(2+) overload and contractile dysfunction via the JAK2/STAT3 pathway. J Mol Cell Cardiol 2015; 81:150-61. [PMID: 25731682 DOI: 10.1016/j.yjmcc.2015.02.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 02/17/2015] [Accepted: 02/19/2015] [Indexed: 01/09/2023]
Abstract
Moderate enhanced reactive oxygen species (ROS) during early reperfusion trigger the cardioprotection against ischemia/reperfusion (I/R) injury, while the mechanism is largely unknown. Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) contributes to the cardioprotection but whether it is activated by ROS and how it regulates Ca(2+) homeostasis remain unclear. Here we investigated whether the ROS generated during early reperfusion protect the heart/cardiomyocyte against I/R-induced Ca(2+) overload and contractile dysfunction via the activation of JAK2/STAT3 signaling pathway by using a cardioprotective model of intermittent hypobaric hypoxia (IHH) preconditioning. IHH improved the postischemic recovery of myocardial contractile performance in isolated rat I/R hearts as well as Ca(2+) homeostasis and cell contraction in simulated I/R cardiomyocytes. Meanwhile, IHH enhanced I/R-increased STAT3 phosphorylation at tyrosine 705 in the nucleus and reversed I/R-suppressed STAT3 phosphorylation at serine 727 in the nucleus and mitochondria during reperfusion. Moreover, IHH improved I/R-suppressed sarcoplasmic reticulum (SR) Ca(2+)-ATPase 2 (SERCA2) activity, enhanced I/R-increased Bcl-2 expression, and promoted the co-localization and interaction of Bcl-2 with SERCA2 during reperfusion. These effects were abolished by scavenging ROS with N-(2-mercaptopropionyl)-glycine (2-MPG) and/or by inhibiting JAK2 with AG490 during the early reperfusion. Furthermore, IHH-improved postischemic SERCA2 activity and Ca(2+) homeostasis as well as cell contraction were reversed after Bcl-2 knockdown by short hairpin RNA. In addition, the reversal of the I/R-suppressed mitochondrial membrane potential by IHH was abolished by 2-MPG and AG490. These results indicate that during early reperfusion the ROS/JAK2/STAT3 pathways play a crucial role in (i) the IHH-maintained intracellular Ca(2+) homeostasis via the improvement of postischemic SERCA2 activity through the increase of SR Bcl-2 and its interaction with SERCA2; and (ii) the IHH-improved mitochondrial function.
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Affiliation(s)
- Lan Wu
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Ji-Liang Tan
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Zhi-Hua Wang
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China; Division of Molecular Medicine, Department of Anesthesiology, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Yi-Xiong Chen
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Ling Gao
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Jin-Long Liu
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Yun-Hua Shi
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China
| | - Masao Endoh
- Department of Pharmacology, Yamagata University School of Medicine, Yamagata, Japan
| | - Huang-Tian Yang
- Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, China.
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Svorc P, Marossy A, Svorc P, Bužga M. Effect of reoxygenation on the electrical stability of the rat heart in vivo: a chronobiological study. Physiol Res 2013; 62:S143-9. [PMID: 24329694 DOI: 10.33549/physiolres.932579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Reoxygenation following hypoxic episodes can increase the risk for the development of ventricular arrhythmias, which, in addition to circadian aspects of reoxygenation arrhythmias has not been studied extensively. The aim of the present study was to evaluate circadian changes in the electrical stability of the rat heart during reoxygenation following a hypoventilatory episode. The electrical stability of the heart, defined in the present study as the ventricular arrhythmia threshold (VAT), was measured at 3 h intervals at clock times 09:00, 12:00, 15:00, 18:00, 21:00, 24:00, 03:00, 06:00 and 09:00 during 20 min hypoventilation (20 breaths/min, tidal volume = 0.5 ml/100 g body weight [n=17]) and subsequent 20 min reoxygenation (50 breaths/min, tidal volume = 1 ml/100 g body weight [n=4]) intervals. The experiments were performed using pentobarbital-anesthetized (40 mg/kg intraperitoneally) female Wistar rats that first underwent a four-week adaptation to a 12 h light:12 h dark regimen. Detailed analysis showed that circadian VATs changed to biphasic rhythms at 10 min of hypoventilation. The VAT circadian rhythms were observed immediately following the commencement of reoxygenation, with the highest values measured between 12:00 and 15:00, and the lowest values between 24:00 and 03:00. These results suggest that myocardial vulnerability is dependent on the light:dark cycle and characteristics of pulmonary ventilation.
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Affiliation(s)
- P Svorc
- Department of Physiology, Medical Faculty, Safarik University, Košice, Slovak Republic.
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Griffiths EJ. Mitochondria and heart disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 942:249-67. [PMID: 22399426 DOI: 10.1007/978-94-007-2869-1_11] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Mitochondria play a key role in the normal functioning of the heart, and in the pathogenesis and development of various types of heart disease. Physiologically, mitochondrial ATP supply needs to be matched to the often sudden changes in ATP demand of the heart, and this is mediated to a large extent by the mitochondrial Ca(2+) transport pathways allowing elevation of mitochondrial [Ca(2+)] ([Ca(2+)](m)). In turn this activates dehydrogenase enzymes to increase NADH and hence ATP supply. Pathologically, [Ca(2+)](m) is also important in generation of reactive oxygen species, and in opening of the mitochondrial permeability transition pore (MPTP); factors involved in both ischaemia-reperfusion injury and in heart failure. The MPTP has proved a promising target for protective strategies, with inhibitors widely used to show cardioprotection in experimental, and very recently human, studies. Similarly mitochondrially-targeted antioxidants have proved protective in various animal models of disease and await clinical trials. The mitochondrial Ca(2+) transport pathways, although in theory promising therapeutic targets, cannot yet be targeted in human studies due to non-specific effects of drugs used experimentally to inhibit them. Finally, specific mitochondrial cardiomyopathies due to mutations in mtDNA have been identified, usually in a gene for a tRNA, which, although rare, are almost always very severe once the mutation has exceeded its threshold.
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Hypoxia followed by re-oxygenation induces oxidation of tyrosine phosphatases. Cell Signal 2011; 23:820-6. [DOI: 10.1016/j.cellsig.2011.01.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 12/09/2010] [Accepted: 01/10/2011] [Indexed: 12/16/2022]
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Ritchie MF, Zhou Y, Soboloff J. Transcriptional mechanisms regulating Ca(2+) homeostasis. Cell Calcium 2010; 49:314-21. [PMID: 21074851 DOI: 10.1016/j.ceca.2010.10.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2010] [Revised: 09/29/2010] [Accepted: 10/01/2010] [Indexed: 01/08/2023]
Abstract
Ca(2+) is a dynamic cellular secondary messenger which mediates a vast array of cellular responses. Control over these processes is achieved via an extensive combination of pumps and channels which regulate the concentration of Ca(2+) within not only the cytosol but also all intracellular compartments. Precisely how these pumps and channels are regulated is only partially understood, however, recent investigations have identified members of the Early Growth Response (EGR) family of zinc finger transcription factors as critical players in this process. The roles of several other transcription factors in control of Ca(2+) homeostasis have also been demonstrated, including Wilms Tumor Suppressor 1 (WT1), Nuclear Factor of Activated T cells (NFAT) and c-myc. In this review, we will discuss not only how these transcription factors regulate the expression of the major proteins involved in control of Ca(2+) homeostasis, but also how this transcriptional remodeling of Ca(2+) homeostasis affects Ca(2+) dynamics and cellular responses.
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Affiliation(s)
- Michael F Ritchie
- Department of Biochemistry, Temple University School of Medicine, Philadelphia, PA 19140, United States
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Tappia PS, Asemu G, Rodriguez-Leyva D. Phospholipase C as a potential target for cardioprotection during oxidative stressThis review is one of a selection of papers published in a Special Issue on Oxidative Stress in Health and Disease. Can J Physiol Pharmacol 2010; 88:249-63. [DOI: 10.1139/y10-019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cardiac dysfunction due to ischemia–reperfusion (I/R) is associated with marked changes in membrane function and subsequent Ca2+-handling abnormalities in cardiomyocytes. The membrane abnormalities in hearts subjected to I/R arise primarily from oxidative stress as a consequence of increased formation of reactive oxygen species and other oxidants, as well as reduced antioxidant defenses. Little is known, however, about the nature and mechanisms of the sarcolemmal membrane changes with respect to phospholipase C (PLC)-related signaling events. In addition, the mechanisms involved in protection of the postischemic myocardium and in ischemic preconditioning with respect to PLC function need to be established. Accordingly, this article reviews the historical and current information on PLC-mediated signal transduction mechanisms in I/R, as well as outlining future directions that should be addressed. Such information will extend our knowledge of ischemic heart disease and help improve its therapy.
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Affiliation(s)
- Paramjit S. Tappia
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Department of Human Nutritional Sciences, Faculty of Human Ecology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Girma Asemu
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Department of Human Nutritional Sciences, Faculty of Human Ecology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Delfin Rodriguez-Leyva
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Department of Human Nutritional Sciences, Faculty of Human Ecology, University of Manitoba, Winnipeg, Manitoba, Canada
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Mitochondrial calcium transport in the heart: Physiological and pathological roles. J Mol Cell Cardiol 2009; 46:789-803. [DOI: 10.1016/j.yjmcc.2009.03.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Revised: 02/28/2009] [Accepted: 03/03/2009] [Indexed: 12/20/2022]
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Sharikabad MN, Aronsen JM, Haugen E, Pedersen J, Møller ASW, Mørk HK, Aass HCD, Sejersted OM, Sjaastad I, Brørs O. Cardiomyocytes from postinfarction failing rat hearts have improved ischemia tolerance. Am J Physiol Heart Circ Physiol 2009; 296:H787-95. [PMID: 19136604 DOI: 10.1152/ajpheart.00796.2008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Altered myocardial Ca(2+) and Na(+) handling in congestive heart failure (CHF) may be expected to decrease the tolerance to ischemia by augmenting reperfusion Ca(2+) overload. The aim of the present study was to investigate tolerance to hypoxia-reoxygenation by measuring enzyme release, cell death, ATP level, and cell Ca(2+) and Na(+) in cardiomyocytes from failing rat hearts. CHF was induced in Wistar rats by ligation of the left coronary artery during isoflurane anesthesia, after which cardiac failure developed within 6 wk. Isolated cardiomyocytes were cultured for 24 h and subsequently exposed to 4 h of hypoxia and 2 h of reoxygenation. Cell damage was measured as lactate dehydrogenase (LD) release, cell death as propidium iodide uptake, and ATP by firefly luciferase assay. Cell Ca(2+) and Na(+) were determined with radioactive isotopes, and free intracellular Ca(2+) concentration ([Ca(2+)](i)) with fluo-3 AM. CHF cells showed less increase in LD release and cell death after hypoxia-reoxygenation and had less relative reduction in ATP level after hypoxia than sham cells. CHF cells accumulated less Na(+) than sham cells during hypoxia (117 vs. 267 nmol/mg protein). CHF cells maintained much lower [Ca(2+)](i) than sham cells during hypoxia (423 vs. 1,766 arbitrary units at 4 h of hypoxia), and exchangeable Ca(2+) increased much less in CHF than in sham cells (1.4 vs. 6.7 nmol/mg protein) after 120 min of reoxygenation. Ranolazine, an inhibitor of late Na(+) current, significantly attenuated both the increase in exchangeable Ca(2+) and the increase in LD release in sham cells after reoxygenation. This supports the suggestion that differences in Na(+) accumulation during hypoxia cause the observed differences in Ca(2+) accumulation during reoxygenation. Tolerance to hypoxia and reoxygenation was surprisingly higher in CHF than in sham cardiomyocytes, probably explained by lower hypoxia-mediated Na(+) accumulation and subsequent lower Ca(2+) accumulation in CHF after reoxygenation.
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Inhibition of matrix metalloproteinases prevents peroxynitrite-induced contractile dysfunction in the isolated cardiac myocyte. Br J Pharmacol 2007; 153:676-83. [PMID: 18071296 DOI: 10.1038/sj.bjp.0707621] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND AND PURPOSE The potent oxidant peroxynitrite (ONOO(-)) induces mechanical dysfunction in the intact heart in part through activation of matrix metalloproteinase-2 (MMP-2). This effect may be independent of the proteolytic actions of MMPs on extracellular matrix proteins. The purpose of this study was to examine the effects of ONOO(-) on contractile function at the level of the single cardiac myocyte and whether this includes the action of MMPs. EXPERIMENTAL APPROACH Freshly isolated ventricular myocytes from adult rats were superfused with Krebs-Henseleit buffer at 21 degrees C and paced at 0.5 Hz. Contractility was measured using a video edge-detector. ONOO(-) or decomposed ONOO(-) (vehicle control) were co-infused over 40 min to evaluate the contraction cease time (CCT). The effects of ONOO(-) on intracellular [Ca(2+)] were determined in myocytes loaded with calcium green-1 AM. MMP-2 activity was measured by gelatin zymography. KEY RESULTS ONOO(-) (30-600 microM) caused a concentration-dependent reduction in CCT. Myocytes subjected to 300 microM ONOO(-) had a shorter CCT than decomposed ONOO(-) (14.9+1.5 vs 32.2+3.5 min, n=7-8; P<0.05) and showed increased MMP-2 activity. The MMP inhibitors doxycycline (100 microM) or PD 166793 (2 microM) reduced the decline in CCT induced by 300 microM ONOO(-). ONOO(-) caused shorter calcium transient cease time and significant alterations in intracellular [Ca(2+)] homoeostasis which were partially prevented by doxycycline. CONCLUSIONS AND IMPLICATIONS This is the first demonstration that inhibition of MMPs protects the cardiac myocyte from ONOO(-)-induced contractile failure via an action unrelated to proteolysis of extracellular matrix proteins.
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Milton SL, Nayak G, Kesaraju S, Kara L, Prentice HM. Suppression of reactive oxygen species production enhances neuronal survival in vitro and in vivo in the anoxia-tolerant turtle Trachemys scripta. J Neurochem 2007; 101:993-1001. [PMID: 17326763 DOI: 10.1111/j.1471-4159.2007.04466.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hypoxia-ischemia with reperfusion is known to cause reactive oxygen species-related damage in mammalian systems, yet, the anoxia tolerant freshwater turtle is able to survive repeated bouts of anoxia/reoxygenation without apparent damage. Although the physiology of anoxia tolerance has been much studied, the adaptations that permit survival of reoxygenation stress have been largely ignored. In this study, we examine ROS production in the turtle striatum and in primary neuronal cultures, and examine the effects of adenosine (AD) on cell survival and ROS. Hydroxyl radical formation was measured by the conversion of salicylate to 2,3-dihydroxybenzoic acid (2,3-DHBA) using microdialysis; reoxygenation after 1 or 4 h anoxia did not result in increased ROS production compared with basal normoxic levels, nor did H(2)O(2) increase after anoxia/reoxygenation in neuronally enriched cell cultures. Blockade of AD receptors increased both ROS production and cell death in vitro, while AD agonists decreased cell death and ROS. As turtle neurons proved surprisingly susceptible to externally imposed ROS stress (H(2)O(2)), we propose that the suppression of ROS formation, coupled to high antioxidant levels, is necessary for reoxygenation survival. As an evolutionarily selected adaptation, the ability to suppress ROS formation could prove an interesting path to investigate new therapeutic targets in mammals.
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Affiliation(s)
- Sarah L Milton
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA.
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Milton SL, Prentice HM. Beyond anoxia: the physiology of metabolic downregulation and recovery in the anoxia-tolerant turtle. Comp Biochem Physiol A Mol Integr Physiol 2006; 147:277-90. [PMID: 17049896 PMCID: PMC1975785 DOI: 10.1016/j.cbpa.2006.08.041] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 08/17/2006] [Accepted: 08/21/2006] [Indexed: 01/05/2023]
Abstract
The freshwater turtle Trachemys scripta is among the most anoxia-tolerant of vertebrates, a true facultative anaerobe able to survive without oxygen for days at room temperature to weeks or months during winter hibernation. Our good friend and colleague Peter Lutz devoted nearly 25 years to the study of the physiology of anoxia tolerance in these and other model organisms, promoting not just the basic science but also the idea that understanding the physiology and molecular mechanisms behind anoxia tolerance provides insights into critical survival pathways that may be applicable to the hypoxic/ischemic mammalian brain. Work by Peter and his colleagues focused on the factors which enable the turtle to enter a deep hypometabolic state, including decreases in ion flux ("channel arrest"), increases in inhibitory neuromodulators like adenosine and GABA, and the maintenance of low extracellular levels of excitatory compounds such as dopamine and glutamate. Our attention has recently turned to molecular mechanisms of anoxia tolerance, including the upregulation of such protective factors as heat shock proteins (Hsp72, Hsc73), the reversible downregulation of voltage gated potassium channels, and the modulation of MAP kinase pathways. In this review we discuss three phases of anoxia tolerance, including the initial metabolic downregulation over the first several hours, the long-term maintenance of neuronal function over days to weeks of anoxia, and finally recovery upon reoxygenation, with necessary defenses against reactive oxygen stress.
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Affiliation(s)
- Sarah L Milton
- Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA.
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Dong F, Fang CX, Yang X, Zhang X, Lopez FL, Ren J. Cardiac overexpression of catalase rescues cardiac contractile dysfunction induced by insulin resistance: Role of oxidative stress, protein carbonyl formation and insulin sensitivity. Diabetologia 2006; 49:1421-33. [PMID: 16586065 DOI: 10.1007/s00125-006-0230-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 02/10/2006] [Indexed: 10/24/2022]
Abstract
AIMS/HYPOTHESIS Insulin resistance leads to oxidative stress and cardiac dysfunction. This study examined the impact of catalase on insulin-resistance-induced cardiac dysfunction, oxidative damage and insulin sensitivity. METHODS Insulin resistance was initiated in FVB and catalase-transgenic mice by 12 weeks of sucrose feeding. Contractile and intracellular Ca2+ properties were evaluated in cardiomyocytes including peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR90), half-width duration (HWD), maximal velocity of shortening/relengthening (+/-dL/dt), fura-fluorescence intensity change (DeltaFFI) and intracellular Ca2+ clearance rate (tau). Reactive oxygen species (ROS) and protein damage were evaluated with dichlorodihydrofluorescein and protein carbonyl formation. RESULTS Sucrose-fed mice displayed hyperinsulinaemia, impaired glucose tolerance and normal body weight. Myocytes from FVB sucrose-fed mice exhibited depressed PS and +/-dL/dt, prolonged TR90 and tau, and reduced DeltaFFI associated with normal TPS and HWD compared with those from starch-fed control mice. ROS and protein carbonyl formation were elevated in FVB sucrose-fed mice. Insulin sensitivity was reduced, evidenced by impaired insulin-stimulated 2-deoxy-D: -[3H]glucose uptake. Western blot analysis indicated that sucrose feeding: (1) inhibited insulin-stimulated phosphorylation of insulin receptor and Akt; (2) enhanced protein-tyrosine phosphatase 1B (PTP1B) expression; and (3) suppressed endothelial nitric oxide synthase (eNOS) and Na+-Ca2+ exchanger expression without affecting peroxisome proliferator-activated receptor gamma (PPARgamma), sarco(endo)plasmic reticulum Ca2+-ATPase isozyme 2a and phospholamban. Catalase ablated insulin-resistance-induced mechanical dysfunction, ROS production and protein damage, and reduced eNOS, but not insulin insensitivity. Catalase itself decreased resting FFI and enhanced expression of PTP1B and PPARgamma. CONCLUSIONS/INTERPRETATION These data indicate that catalase rescues insulin-resistance-induced cardiac dysfunction related to ROS production and protein oxidation but probably does not improve insulin sensitivity.
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Affiliation(s)
- F Dong
- Division of Pharmaceutical Sciences and Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, 1000 E. University Avenue, Department 3375, Laramie, WY 82071, USA
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Park J, Bansal T, Pinelis M, Maharbiz MM. A microsystem for sensing and patterning oxidative microgradients during cell culture. LAB ON A CHIP 2006; 6:611-22. [PMID: 16652176 DOI: 10.1039/b516483d] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present the design, modeling, fabrication and testing of a microsystem for the electrolytic patterning and sensing of oxidative microgradients within 1 x 1 mm2 area during cell culture. The system employs an array of microfabricated electrodes (3-40 microm in width) embedded in gas-permeable microchannels to generate precise doses of dissolved oxygen (ranging from 10 fmol O2 mm(-2) s(-1) to 100 nmol O2 mm(-2) s(-1)) via electrolysis. The microgradients generated by different microelectrodes in the array can be superimposed to pattern multi-dimensional oxygen profiles not possible with other methods. We demonstrate the patterning, sensing and quantification of dissolved oxygen microgradients in the 0 to 40% dO2 range using this microsystem. Reactive oxygen species generation and dosing is also quantified. Lastly, we demonstrate how the microtechnology enables new types of experiments in three different cell culture models: localized hyperoxia-induced apoptosis in C2C12 myoblasts, dynamic aerotaxis assays of Bacillus subtilis, and studies of calcium release in an ischemia/re-oxygenation myoblast model.
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Affiliation(s)
- Jaehyun Park
- Electrical Engineering and Computer Science Department, University of Michigan, Ann Arbor, 1301 Beal Ave., Ann Arbor, MI 48109-2122, USA.
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