151
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Zielinski ZAM, Pratt DA. Cholesterol Autoxidation Revisited: Debunking the Dogma Associated with the Most Vilified of Lipids. J Am Chem Soc 2016; 138:6932-5. [DOI: 10.1021/jacs.6b03344] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Zosia A. M. Zielinski
- Department of Chemistry and
Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
| | - Derek A. Pratt
- Department of Chemistry and
Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
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152
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Niki E. Antioxidant capacity of foods for scavenging reactive oxidants and inhibition of plasma lipid oxidation induced by multiple oxidants. Food Funct 2016; 7:2156-68. [PMID: 27090496 DOI: 10.1039/c6fo00275g] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Unregulated oxidation of biological molecules induced by multiple oxidants has been implicated in the pathogenesis of various diseases. Consequently, the effects of antioxidants contained in foods, beverages and supplements on the maintenance of health and prevention of diseases have attracted much attention of the public as well as scientists. However, recent human studies have shown inconsistent results and failed to demonstrate the beneficial effects of antioxidants. The mechanisms and dynamics of antioxidant action and assessment of antioxidant capacity have been the subject of extensive studies and arguments. In the present article, the antioxidant capacity has been reviewed focusing on two main issues: the capacity of antioxidants to scavenge multiple reactive oxidants and to inhibit plasma lipid oxidation induced by different biological oxidants. It is emphasized that the capacity of antioxidants to scavenge reactive oxidants does not always correlate linearly with the capacity to inhibit lipid oxidation and that it is necessary to specify the oxidant to assess the efficacy of antioxidants, since multiple oxidants contribute to oxidative damage in vivo and the effects of antioxidants depend on the nature of oxidants. A convenient and rapid method using a microplate reader is discussed for assessing the antioxidant capacity against plasma lipid oxidation induced by multiple oxidants including peroxyl radicals, peroxynitrite, hypochlorite, 15-lipoxygenase, and singlet oxygen.
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Affiliation(s)
- Etsuo Niki
- Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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153
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Shiva Ayyadurai VA, Hansen M, Fagan J, Deonikar P. <i>In-Silico</i> Analysis & <i>In-Vivo</i> Results Concur on Glutathione Depletion in Glyphosate Resistant GMO Soy, Advancing a Systems Biology Framework for Safety Assessment of GMOs. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/ajps.2016.712149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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154
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Yang WS, Stockwell BR. Ferroptosis: Death by Lipid Peroxidation. Trends Cell Biol 2015; 26:165-176. [PMID: 26653790 DOI: 10.1016/j.tcb.2015.10.014] [Citation(s) in RCA: 1770] [Impact Index Per Article: 196.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 10/25/2015] [Accepted: 10/26/2015] [Indexed: 02/06/2023]
Abstract
Ferroptosis is a regulated form of cell death driven by loss of activity of the lipid repair enzyme glutathione peroxidase 4 (GPX4) and subsequent accumulation of lipid-based reactive oxygen species (ROS), particularly lipid hydroperoxides. This form of iron-dependent cell death is genetically, biochemically, and morphologically distinct from other cell death modalities, including apoptosis, unregulated necrosis, and necroptosis. Ferroptosis is regulated by specific pathways and is involved in diverse biological contexts. Here we summarize the discovery of ferroptosis, the mechanism of ferroptosis regulation, and its increasingly appreciated relevance to both normal and pathological physiology.
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Affiliation(s)
- Wan Seok Yang
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, NY, USA.
| | - Brent R Stockwell
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, NY, USA; Department of Chemistry, Columbia University, New York, NY, USA; Department of Systems Biology, Columbia University, New York, NY, USA.
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155
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Sirick A, Lednev S, Moskalenko I, Machtin V, Pliss E. Kinetic features of chain initiation reactions during the oxidation of unsaturated compounds in media of different polarity. REACTION KINETICS MECHANISMS AND CATALYSIS 2015. [DOI: 10.1007/s11144-015-0957-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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156
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Elmasry SA, Al-Azzawi MA, Ghoneim AH, Nasr MY, AboZaid MM. Role of oxidant–antioxidant imbalance in the pathogenesis of chronic obstructive pulmonary disease. EGYPTIAN JOURNAL OF CHEST DISEASES AND TUBERCULOSIS 2015. [DOI: 10.1016/j.ejcdt.2015.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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157
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Saito Y, Shichiri M, Hamajima T, Ishida N, Mita Y, Nakao S, Hagihara Y, Yoshida Y, Takahashi K, Niki E, Noguchi N. Enhancement of lipid peroxidation and its amelioration by vitamin E in a subject with mutations in the SBP2 gene. J Lipid Res 2015; 56:2172-82. [PMID: 26411970 PMCID: PMC4617404 DOI: 10.1194/jlr.m059105] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Indexed: 02/05/2023] Open
Abstract
Selenocysteine (Sec) insertion sequence-binding protein 2 (SBP2) is essential for the biosynthesis of Sec-containing proteins, termed selenoproteins. Subjects with mutations in the SBP2 gene have decreased levels of several selenoproteins, resulting in a complex phenotype. Selenoproteins play a significant role in antioxidative defense, and deficiencies in these proteins can lead to increased oxidative stress. However, lipid peroxidation and the effects of antioxidants in subjects with SBP2 gene mutations have not been studied. In the present study, we evaluated the lipid peroxidation products in the blood of a subject (the proband) with mutations in the SBP2 gene. We found that the proband had higher levels of free radical-mediated lipid peroxidation products, such as 7β-hydroxycholesterol, than the control subjects. Treatment of the proband with vitamin E (α-tocopherol acetate, 100 mg/day), a lipid-soluble antioxidant, for 2 years reduced lipid peroxidation product levels to those of control subjects. Withdrawal of vitamin E treatment for 7 months resulted in an increase in lipid peroxidation products. Collectively, these results clearly indicate that free radical-mediated oxidative stress is increased in the subject with SBP2 gene mutations and that vitamin E treatment effectively inhibits the generation of lipid peroxidation products.
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Affiliation(s)
- Yoshiro Saito
- Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan
| | - Mototada Shichiri
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Takashi Hamajima
- Department of Pediatric Endocrinology and Metabolism, Aichi Children's Health and Medical Center, Obu, Aichi 474-8710, Japan
| | - Noriko Ishida
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Yuichiro Mita
- Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan
| | - Shohei Nakao
- Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan
| | - Yoshihisa Hagihara
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Yasukazu Yoshida
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Kazuhiko Takahashi
- Department of Nutritional Biochemistry, Hokkaido Pharmaceutical University, Otaru, Hokkaido 047-0264, Japan
| | - Etsuo Niki
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Noriko Noguchi
- Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan
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158
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Li B, Zheng F, Chauvin JPR, Pratt DA. The medicinal thiosulfinates from garlic and Petiveria are not radical-trapping antioxidants in liposomes and cells, but lipophilic analogs are. Chem Sci 2015; 6:6165-6178. [PMID: 30090232 PMCID: PMC6054074 DOI: 10.1039/c5sc02270c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 07/27/2015] [Indexed: 01/11/2023] Open
Abstract
The radical-trapping antioxidant (RTA) activities of allicin and petivericin, thiosulfinates widely believed responsible for the medicinal properties of garlic and Petiveria, were determined in phosphatidylcholine lipid bilayers and mammalian cell culture.
The radical-trapping antioxidant (RTA) activities of allicin and petivericin, thiosulfinates widely believed responsible for the medicinal properties of garlic and Petiveria, were determined in phosphatidylcholine lipid bilayers. The results indicate that both compounds are surprisingly ineffective, in sharp contrast with previous studies in organic solution which showed that they undergo facile Cope elimination to produce sulfenic acids – potent radical-trapping agents. In an effort to understand the medium dependence of this activity, a more lipophilic (hexylated) analog of petivericin was synthesized and shown to be among the most effective RTAs known, but only in the presence of a hydrophilic thiol (e.g. N-acetylcysteine). Additional symmetric and unsymmetric thiosulfinates were synthesized to shed light on the structural features that underlie this reactivity. These studies reveal that amphiphilic thiosulfinates which undergo S-thiolation with a hydrophilic thiol to give lipophilic sulfenic acids are required, and that an activated methylene group – key to promote Cope elimination – is not. Interestingly, the added thiol was also found to regenerate the sulfenic acid following its reaction with peroxyl radicals. This activity was diminished at more acidic pH, suggesting that it occurs by electron transfer from the thiolate. Allicin, petivericin and hexylated petivericin were assayed as inhibitors of lipid peroxidation in human TF1a erythroblasts and HEK-293 kidney cells, revealing similar efficacies in the low μM range – the same range in which allicin and petivericin were found to induce cell death concomitant with, or as a result of, glutathione (GSH) depletion. In contrast, hexylated petivericin was not cytotoxic throughout the concentration range assayed, and had no effect on GSH levels. Taken together, the results in lipid bilayers and in cell culture suggest that the greater lipophilicity of hexylated petivericin enables it to partition to membranous cell compartments where it forms a lipid-soluble sulfenic acid that traps peroxyl radicals, whereas allicin and petivericin partition to the cytosol where they deplete GSH and induce cell death.
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Affiliation(s)
- Bo Li
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , 10 Marie Curie Pvt. , Ottawa , Ontario , Canada . ; ; Tel: +1-613-562-5800 ext. 2119
| | - Feng Zheng
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , 10 Marie Curie Pvt. , Ottawa , Ontario , Canada . ; ; Tel: +1-613-562-5800 ext. 2119
| | - Jean-Philippe R Chauvin
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , 10 Marie Curie Pvt. , Ottawa , Ontario , Canada . ; ; Tel: +1-613-562-5800 ext. 2119
| | - Derek A Pratt
- Department of Chemistry and Biomolecular Sciences , University of Ottawa , 10 Marie Curie Pvt. , Ottawa , Ontario , Canada . ; ; Tel: +1-613-562-5800 ext. 2119
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159
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Li B, Pratt DA. Methods for determining the efficacy of radical-trapping antioxidants. Free Radic Biol Med 2015; 82:187-202. [PMID: 25660993 DOI: 10.1016/j.freeradbiomed.2015.01.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/20/2015] [Accepted: 01/22/2015] [Indexed: 01/10/2023]
Abstract
Hydrocarbon autoxidation is the free radical chain reaction primarily responsible for the oxidative degradation of organic materials, including those that make up cells, tissues, and organs. The identification of compounds that slow this process (antioxidants) and the quantitation of their efficacies have long been goals of academic and industrial researchers. Antioxidants are generally divided into two types: preventive and radical-trapping (also commonly referred to as chain-breaking). Preventive antioxidants slow the rate of initiation of autoxidation, whereas radical-trapping antioxidants slow the rate of propagation by reacting with chain-propagating peroxyl radicals. The purpose of this review is to provide a comprehensive overview of different approaches to measure the kinetics of the reactions of radical-trapping antioxidants with peroxyl radicals, and their use to study the inhibition of hydrocarbon (lipid) autoxidation in homogeneous solution, as well as biphasic media (lipid bilayers) and cell culture. Direct and indirect approaches are presented and advantages and disadvantages of each are discussed in order to facilitate method selection for investigators seeking to address particular questions in this immensely popular field.
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Affiliation(s)
- Bo Li
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Derek A Pratt
- Department of Chemistry, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada.
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160
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Yuan T, Fan WB, Cong Y, Xu HD, Li CJ, Meng J, Bao NR, Zhao JN. Linoleic acid induces red blood cells and hemoglobin damage via oxidative mechanism. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:5044-5052. [PMID: 26191198 PMCID: PMC4503070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 04/15/2015] [Indexed: 06/04/2023]
Abstract
Hidden blood loss typically occurs following total hip arthroplasty (THA) and total knee arthroplasty (TKA) and is thought to be related to free fatty acid (FFA). To study the effect of linoleic acid on red blood cells and to examine the pathogenesis of hidden blood loss in vivo, we generated an animal model by injecting linoleic acid into the tail veins of rats. We collected blood samples and determined red blood cell count (RBC) and levels of hemoglobin (Hb), as well as the oxidation and reducing agents in the blood, including glutathione peroxidase (GSH-PX), total superoxide dismutase (T-SOD), hydrogen peroxide (H2O2), and ferryl hemoglobin (Fe4+=O2-), which is generated by the oxidation of Hb. Hidden blood loss occurred when linoleic acid was administered at a concentration of 60 mmol/L; RBC and Hb levels were significantly reduced by 24 h post-injection. This was followed by erythrocyte deformation, reduced activity of GSH-PX and T-SOD, and decreased levels of H2O2. This was accompanied by an increase in ferryl species, which likely contributes to oxidative stress in vivo. Our findings suggest that linoleic acid enhances acute red blood cell injury. Hb and RBC began to increase by 72 h, potentially resulting from linoleic acid metabolism. Thus, elevated levels of linoleic acid in the blood cause acute oxidative damage to red blood cells, eventually leading to partial acute anemia. These findings highlight the pathophysiology underlying hidden blood loss.
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Affiliation(s)
- Tao Yuan
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Wen-Bin Fan
- Department of Orthopedic, Jinling Hospital, Tangshan Sanitarium211131, China
| | - Yu Cong
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Hai-Dong Xu
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Cheng-Jun Li
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Jia Meng
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Ni-Rong Bao
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
| | - Jian-Ning Zhao
- Department of Orthopedic, Jinling Hospital, School of Medical Nanjing UniversityNanjing 210002, Peoples R China
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161
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Ito J, Mizuochi S, Nakagawa K, Kato S, Miyazawa T. Tandem Mass Spectrometry Analysis of Linoleic and Arachidonic Acid Hydroperoxides via Promotion of Alkali Metal Adduct Formation. Anal Chem 2015; 87:4980-7. [DOI: 10.1021/acs.analchem.5b00851] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Junya Ito
- Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8577, Japan
| | - Shunsuke Mizuochi
- Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8577, Japan
| | - Kiyotaka Nakagawa
- Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8577, Japan
| | - Shunji Kato
- Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8577, Japan
| | - Teruo Miyazawa
- Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8577, Japan
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162
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Effect of atorvastatin on serum oxidative stress and N-terminal brain natriuretic peptide expression in rats. ASIAN PAC J TROP MED 2015; 7:398-401. [PMID: 25063069 DOI: 10.1016/s1995-7645(14)60064-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 01/15/2014] [Accepted: 03/15/2014] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To investigate the effect of atorvastatin on serum oxidative stress and N-terminal brain natriuretic peptide expression in rats. METHODS A total of 40 healthy male SD rats were randomly divided into the sham group (Group A, n=10, saline 5 mL/d), ischemia-reperfusion group (Group B, n=10, saline 5 mL/d), atorvastatin group (Group C, n=10, atorvastatin 20 mg/kg · d), atorvastatin + N-amino-arginine group (Group D, n=10, atorvastatin 20 mg/kg · d + N-amino arginine 15 mg/kg). Myocardial ischemia-reperfusion rat model was established after 3 days of gavage. N-amino arginine 15 mg/kg was given by tail vein injection 15 min before ischemia. After reperfusion, enzymology indicators such us creatine kinase (CK) and lactate dehydrogenase and the oxidative stress parameters such as nitric oxide (NO), malondialdehyde (MDA) and total superoxide dismutase (TSOD), and n-terminal pro-brain natriuretic peptide (NT-proBNP) expression was detected by immunohistochemistry. RESULTS LDH and CK levels of group A were significantly lower than the other three groups, and group B was the highest. There was significant difference between group B and group C (P<0.05), and no significant difference between group B and group D (P>0.05). MDA levels in group B were significantly higher than the other three groups. The lowest was group A, followed by group C, the difference among groups was significantly (P<0.05). TSOD and NO levels in group B was the lowest, the level in group A was the highest, followed by group C, the difference among groups was significant (P<0.05). NT-proBNP level in group B was significantly higher than the other three groups, the lowest was group A, followed by group C, the difference among groups was significant (P<0.05). CONCLUSIONS Atorvastatin has a protective effect on the myocardial injury in the myocardial ischemia and reperfusion rats. It can increase NO synthesis and decrease MDA content, increase serum TSOD activity and the oxidative stress effect, meanwhile protect myocardial cells and reduce myocardial injury.
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163
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Pliss EM, Loshadkin DV, Grobov AM, Kuznetsova TS, Rusakov AI. Kinetic study and simulation of methyl linoleate oxidation in micelles. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2015. [DOI: 10.1134/s1990793115010091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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164
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Zuo L, Best TM, Roberts WJ, Diaz PT, Wagner PD. Characterization of reactive oxygen species in diaphragm. Acta Physiol (Oxf) 2015; 213:700-10. [PMID: 25330121 DOI: 10.1111/apha.12410] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/19/2014] [Accepted: 10/16/2014] [Indexed: 12/17/2022]
Abstract
Reactive oxygen species (ROS) exist as natural mediators of metabolism to maintain cellular homeostasis. However, ROS production may significantly increase in response to environmental stressors, resulting in extensive cellular damage. Although several potential sources of increased ROS have been proposed, exact mechanisms of their generation have not been completely elucidated. This is particularly true for diaphragmatic skeletal muscle, the key muscle used for respiration. Several experimental models have focused on detection of ROS generation in rodent diaphragm tissue under stressful conditions, including hypoxia, exercise, and heat, as well as ROS formation in single myofibres. Identification methods include direct detection of ROS with confocal or fluorescent microscopy and indirect detection of ROS through end product analysis. This article explores implications of ROS generation and oxidative stress, and also evaluates potential mechanisms of cellular ROS formation in diaphragmatic skeletal muscle.
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Affiliation(s)
- L. Zuo
- Radiologic Sciences and Respiratory Therapy Division; School of Health and Rehabilitation Sciences; The Ohio State University College of Medicine; The Ohio State University Wexner Medical Center; Columbus OH USA
| | - T. M. Best
- Division of Sports Medicine; Department of Family Medicine Sports Health and Performance Institute; The Ohio State University; Columbus OH USA
| | - W. J. Roberts
- Radiologic Sciences and Respiratory Therapy Division; School of Health and Rehabilitation Sciences; The Ohio State University College of Medicine; The Ohio State University Wexner Medical Center; Columbus OH USA
| | - P. T. Diaz
- Division of Pulmonary, Allergy, Critical Care & Sleep Medicine; The Ohio State University Wexner Medical Center; Columbus OH USA
| | - P. D. Wagner
- Department of Medicine; University of California, San Diego; La Jolla CA USA
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165
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Direct separation of the diastereomers of phosphatidylcholine hydroperoxide bearing 13-hydroperoxy-9Z,11E-octadecadienoic acid using chiral stationary phase high-performance liquid chromatography. J Chromatogr A 2015; 1386:53-61. [DOI: 10.1016/j.chroma.2015.01.080] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/26/2015] [Accepted: 01/27/2015] [Indexed: 11/23/2022]
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166
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Valdés A, Beltrán A, Karabagias I, Badeka A, Kontominas MG, Garrigós MC. Monitoring the oxidative stability and volatiles in blanched, roasted and fried almonds under normal and accelerated storage conditions by DSC, thermogravimetric analysis and ATR-FTIR. EUR J LIPID SCI TECH 2015. [DOI: 10.1002/ejlt.201400384] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Arantzazu Valdés
- Analytical Chemistry; Nutrition & Food Sciences Department; University of Alicante; Alicante Spain
| | - Ana Beltrán
- Analytical Chemistry; Nutrition & Food Sciences Department; University of Alicante; Alicante Spain
| | - Ioannis Karabagias
- Laboratory of Food Chemistry and Technology; Department of Chemistry; University of Ioannina; Ioannina Greece
| | - Anastasia Badeka
- Laboratory of Food Chemistry and Technology; Department of Chemistry; University of Ioannina; Ioannina Greece
| | - Michael G. Kontominas
- Laboratory of Food Chemistry and Technology; Department of Chemistry; University of Ioannina; Ioannina Greece
| | - María Carmen Garrigós
- Analytical Chemistry; Nutrition & Food Sciences Department; University of Alicante; Alicante Spain
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167
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Matsuura BS, Keylor MH, Li B, Lin Y, Allison S, Pratt DA, Stephenson CRJ. A scalable biomimetic synthesis of resveratrol dimers and systematic evaluation of their antioxidant activities. Angew Chem Int Ed Engl 2015; 54:3754-7. [PMID: 25650836 DOI: 10.1002/anie.201409773] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 11/11/2014] [Indexed: 01/12/2023]
Abstract
An efficient synthetic route to the resveratrol oligomers quadrangularin A and pallidol is reported. It features a scalable biomimetic oxidative dimerization that proceeds in excellent yield and with complete regioselectivity. A systematic evaluation of the natural products and their synthetic precursors as radical-trapping antioxidants has revealed that, contrary to popular belief, this mode of action is unlikely to account for their observed biological activity.
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Affiliation(s)
- Bryan S Matsuura
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 (USA)
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168
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Ischaemic conditioning strategies reduce ischaemia/reperfusion-induced organ injury. Br J Anaesth 2015; 114:204-16. [DOI: 10.1093/bja/aeu302] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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169
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Matsuura BS, Keylor MH, Li B, Lin Y, Allison S, Pratt DA, Stephenson CRJ. A Scalable Biomimetic Synthesis of Resveratrol Dimers and Systematic Evaluation of their Antioxidant Activities. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201409773] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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170
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Muchalski H, Levonyak AJ, Xu L, Ingold KU, Porter NA. Competition H(D) kinetic isotope effects in the autoxidation of hydrocarbons. J Am Chem Soc 2015; 137:94-7. [PMID: 25533605 PMCID: PMC4710063 DOI: 10.1021/ja511434j] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrogen atom transfer is central to many important radical chain sequences. We report here a method for determination of both the primary and secondary isotope effects for symmetrical substrates by the use of NMR. Intramolecular competition reactions were carried out on substrates having an increasing number of deuterium atoms at symmetry-related sites. Products that arise from peroxyl radical abstraction at each position of the various substrates reflect the competition rates for H(D) abstraction. The primary KIE for autoxidation of tetralin was determined to be 15.9 ± 1.4, a value that exceeds the maximum predicted by differences in H(D) zero-point energies (∼7) and strongly suggests that H atom abstraction by the peroxyl radical occurs with substantial quantum mechanical tunneling.
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Affiliation(s)
- Hubert Muchalski
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Alexander J. Levonyak
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Libin Xu
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Keith U. Ingold
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Ned A. Porter
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
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171
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Gervasoni BD, Khairallah GN, O'Hair RAJ, Wille U. The role of peroxyl radicals in polyester degradation – a mass spectrometric product and kinetic study using the distonic radical ion approach. Phys Chem Chem Phys 2015; 17:9212-21. [DOI: 10.1039/c4cp06056c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mass spectrometric techniques were employed to reveal detailed insight into the reaction of peroxyl radicals with structural motifs in polyesters.
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Affiliation(s)
- B. D. Gervasoni
- School of Chemistry and Bio21 Institute
- The University of Melbourne
- Parkville
- Australia
| | - G. N. Khairallah
- School of Chemistry and Bio21 Institute
- The University of Melbourne
- Parkville
- Australia
| | - R. A. J. O'Hair
- School of Chemistry and Bio21 Institute
- The University of Melbourne
- Parkville
- Australia
| | - U. Wille
- School of Chemistry and Bio21 Institute
- The University of Melbourne
- Parkville
- Australia
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172
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Yoshida Y, Umeno A, Akazawa Y, Shichiri M, Murotomi K, Horie M. Chemistry of Lipid Peroxidation Products and Their Use as Biomarkers in Early Detection of Diseases. J Oleo Sci 2015; 64:347-56. [DOI: 10.5650/jos.ess14281] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yasukazu Yoshida
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
| | - Aya Umeno
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
| | - Yoko Akazawa
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
| | - Mototada Shichiri
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
| | - Kazutoshi Murotomi
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
| | - Masanori Horie
- Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST)
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173
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Lokhmatikov AV, Voskoboynikova NE, Cherepanov DA, Sumbatyan NV, Korshunova GA, Skulachev MV, Steinhoff HJ, Skulachev VP, Mulkidjanian AY. Prevention of peroxidation of cardiolipin liposomes by quinol-based antioxidants. BIOCHEMISTRY (MOSCOW) 2014; 79:1081-100. [DOI: 10.1134/s0006297914100101] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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174
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Hammond BR, Johnson BA, George ER. Oxidative photodegradation of ocular tissues: beneficial effects of filtering and exogenous antioxidants. Exp Eye Res 2014; 129:135-50. [PMID: 25236792 DOI: 10.1016/j.exer.2014.09.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/11/2014] [Accepted: 09/13/2014] [Indexed: 01/17/2023]
Abstract
The fact that light is necessary for life is generally accepted as an axiom. The extent to which light interacts and influences human biology, however, is often not fully appreciated. Exposure to sunlight, for instance, can both promote and degrade human health. There is now general scientific consensus that, although the eye evolved to respond to light, it is also damaged by excessive exposure. Light-mediated ocular damage is involved in the pathophysiology of many common forms of blindness. The type of ocular tissue damage induced by light exposure depends on the extent of exposure and wavelength. The tissues of the lens, cornea, and retina contain specific chemical moieties that have been proven to exhibit light-mediated oxidative degradation. Proteins and lipids present in the cornea, lens, and retina, meet all of the physical requirements known to initiate the process of oxidative photodegradation upon exposure to solar radiation. As such, different mechanisms have evolved in the lens, cornea, and retina to ameliorate such light-mediated oxidative damage. It appears, however, that such mechanisms are ill-matched to handle modern conditions: namely, poor diet and longer life-spans (and the degenerative diseases that accompany them). Hence, steps must be taken to protect the eye from the damaging effects of light. Preventative measures include minimizing actinic light exposure, providing exogenous filtering (e.g., through the use of protective lenses), and enhancing antioxidant defenses (e.g., through increased dietary intake of antioxidants). These strategies may yield long-term benefits in terms of reducing oxidative photodegradation of the ocular tissues.
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Affiliation(s)
- Billy R Hammond
- Vision Sciences Laboratory, University of Georgia, Athens, GA 30602-3013, USA.
| | - Bart A Johnson
- Johnson & Johnson Vision Care, Inc., 7500 Centurion Parkway, R&D 3rd Floor W3A, Jacksonville, FL 33256, USA
| | - Eric R George
- Johnson & Johnson Vision Care, Inc., 7500 Centurion Parkway, R&D 3rd Floor W3A, Jacksonville, FL 33256, USA.
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175
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Ingold KU, Pratt DA. Advances in radical-trapping antioxidant chemistry in the 21st century: a kinetics and mechanisms perspective. Chem Rev 2014; 114:9022-46. [PMID: 25180889 DOI: 10.1021/cr500226n] [Citation(s) in RCA: 326] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Keith U Ingold
- National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
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176
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177
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Zamora R, Alcón E, Hidalgo FJ. Ammonia and formaldehyde participate in the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in addition to creati(ni)ne and phenylacetaldehyde. Food Chem 2014; 155:74-80. [DOI: 10.1016/j.foodchem.2014.01.039] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/08/2014] [Accepted: 01/14/2014] [Indexed: 11/28/2022]
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178
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Tzeng YZ, Hu CH. Radical-induced Cis-Trans isomerization of fatty acids: a theoretical study. J Phys Chem A 2014; 118:4554-64. [PMID: 24911614 DOI: 10.1021/jp502434t] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Trans fatty acids (TFAs) create deleterious effects; thus their existence in humans is a great health concern. TFAs can be obtained through diet, or they can be formed endogenously by radical-induced cis to trans isomerization. The mechanism of isomerization of fatty acid catalyzed by radicals including nitrogen dioxide (NO2(•)), thiyl (RS(•)), and peroxide (ROO(•)) radicals were investigated using density functional theory. With linoleic acid, a fatty acid consisting of two homoconjugated C═C bonds, we found that the radical addition mechanism is more favorable than the hydrogen abstraction mechanism. For all investigated radicals, the isomerization catalyzed by RS(•) radical involves the smallest reaction barrier. We found that NO2(•) reactions through the N-terminus are more favorable than reactions through the O-terminus. The reaction barriers for NO2(•) catalyzed isomerizations were found to be lowered to a larger extent in polar solvent. β-carotene and lycopene were shown to protect fatty acids from isomerization by intercepting the isomerization-causing radicals.
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Affiliation(s)
- Yu-Zan Tzeng
- Department of Chemistry, National Changhua University of Education , Changhua 50058, Taiwan
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179
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Garrec J, Monari A, Assfeld X, Mir LM, Tarek M. Lipid Peroxidation in Membranes: The Peroxyl Radical Does Not "Float". J Phys Chem Lett 2014; 5:1653-1658. [PMID: 26270361 DOI: 10.1021/jz500502q] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Lipid peroxidation is a fundamental phenomenon in biology and medicine involved in a wide range of diseases. Some key microscopic aspects of this reaction in cell membranes are still poorly studied. In particular, it is commonly accepted that the propagation of the radical reaction in lipid bilayers is hampered by the rapid diffusion of peroxyl intermediates toward the water interface, that is, out of the reaction region. We investigated the validity of this "floating peroxyl radical" hypothesis by means of molecular modeling. Combining quantum calculations of model systems and atomistic simulations of lipid bilayers containing lipid oxidation products, we show that the peroxyl radical does not "float" at the surface of the membrane. Instead, it remains located quite deep inside the bilayer. In light of our findings, several critical aspects of biological membranes' peroxidation, such as their protection mechanisms, need to be revisited. Our data moreover help in the design of more efficient antioxidants, localized within reach of the reaction propagating radical.
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Affiliation(s)
- Julian Garrec
- †Théorie-Modélisation-Simulation, SRSMC, CNRS, Vandoeuvre-lès-Nancy F-54506, France
- ‡Théorie-Modélisation-Simulation, SRSMC, Université de Lorraine, Vandoeuvre-lès-Nancy F-54506, France
| | - Antonio Monari
- †Théorie-Modélisation-Simulation, SRSMC, CNRS, Vandoeuvre-lès-Nancy F-54506, France
- ‡Théorie-Modélisation-Simulation, SRSMC, Université de Lorraine, Vandoeuvre-lès-Nancy F-54506, France
| | - Xavier Assfeld
- †Théorie-Modélisation-Simulation, SRSMC, CNRS, Vandoeuvre-lès-Nancy F-54506, France
- ‡Théorie-Modélisation-Simulation, SRSMC, Université de Lorraine, Vandoeuvre-lès-Nancy F-54506, France
| | - Lluis M Mir
- ¶Laboratoire de Vectorologie et Thérapeutiques Anticancéreuses, Université Paris-Sud, UMR 8203, Orsay F-91405, France
- §Laboratoire de Vectorologie et Thérapeutiques Anticancéreuses, CNRS, UMR 8203, Orsay F-91405, France
- ∥Laboratoire de Vectorologie et Thérapeutiques Anticancéreuses, Gustave Roussy, UMR 8203, Villjuif F-94805, France
| | - Mounir Tarek
- †Théorie-Modélisation-Simulation, SRSMC, CNRS, Vandoeuvre-lès-Nancy F-54506, France
- ‡Théorie-Modélisation-Simulation, SRSMC, Université de Lorraine, Vandoeuvre-lès-Nancy F-54506, France
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180
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Khairallah GN, O'Hair RAJ, Wille U. Mass spectrometric and computational studies on the reaction of aromatic peroxyl radicals with phenylacetylene using the distonic radical ion approach. J Phys Chem A 2014; 118:3295-306. [PMID: 24712711 DOI: 10.1021/jp411477e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Product and mechanistic studies were performed for the reaction of aromatic distonic peroxyl radical cations 4-PyrOO(•+) and 3-PyrOO(•+) with phenylacetylene (7) in the gas phase using mass spectrometric and computational techniques. PyrOO(•+) was generated through reaction of the respective distonic aryl radical cation Pyr(•+) with O2 in the ion source of the mass spectrometer. For the reaction involving the more electrophilic 4-PyrOO(•+), a rate coefficient of k1 = (2.2 ± 0.6) × 10(-10) cm(3) molecule(-1) s(-1) was determined at 298 K, while a value of k2 = (8.2 ± 2.1) × 10(-11) cm(3) molecule(-1) s(-1) was obtained for the reaction involving the less electrophilic 3-PyrOO(•+). This highlights the role of polar effects in these reactions, which are likely of high relevance for processes in combustions and atmospheric transformations. The mechanism was studied by computational methods, which showed that radical addition occurs exclusively at the less substituted alkyne site to give the distonic vinyl radical cation 8. The latter undergoes a series of subsequent rearrangements/fragmentations that are similar for both isomeric PyrOO(•+). γ-Fragmentation in 8 leads to the distonic aryloxyl radical cation PyrO(•+) and a singlet carbene 10. The product association complex [PyrO(•+) - 10] is the starting point for two important subsequent reactions, e.g., (i) rapid hydrogen transfer to form ketenyl radical 11 and the closed-shell species PyrOH(+), and (ii) oxygen transfer from PyrO(•+) to 10 that leads to α-keto aldehyde 13 and Pyr(•+), followed by hydrogen abstraction to give acyl radical 14 and PyrH(+). Additional major products are the closed-shell aromatic carbonyl compounds 20 and 30 that result from multistep rearrangements in vinyl radical 8, which are terminated by homolytic bond scission and release of neutral acyl radicals.
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Affiliation(s)
- George N Khairallah
- School of Chemistry and Bio21 Institute, ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, The University of Melbourne , 30 Flemington Road, Parkville, Victoria 3010, Australia
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181
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182
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Abstract
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7-Dehydrocholesterol (7-DHC) is the
most oxidizable lipid molecule
reported to date, with a propagation rate constant for free radical
peroxidation that is 200 times that of cholesterol. To better understand
the high reactivity of 7-DHC and elucidate the reaction mechanism,
we synthesized conjugated and skipped nonconjugated cholestadienols
that would give one of the two putative pentadienyl-radical intermediates
formed in 7-DHC peroxidation. The additional dienols include 6,8(9)-dienol,
5,8(14)-dienol, 6,8(14)-dienol, and the biologically important 8-dehydrocholesterol
(8-DHC; 5,8(9)-dienol). We found that all of the dienols are significantly
(at least 40 times) more reactive than cholesterol. Among them, dienols
leading to the formation of the pentadienyl radical in ring B (termed endo-B) of the sterol are more reactive than
those leading to the pentadienyl radical spanning rings B and C (termed exo-B). By comparing the oxysterol profile
formed from 7-DHC and those formed from 8-DHC and 5,8(14)-dienol,
products formed from abstraction of the hydrogen atoms at C-9 and
C-14 (H-9 or H-14 mechanism) were
clearly differentiated. When the oxidation was carried out in the
presence of the good hydrogen atom donor α-tocopherol, the oxysterol
profile of 7-DHC peroxidation differed distinctly from the profile
observed in the absence of the antioxidant and resembles more closely
the profile observed in biological systems. This study suggests that
oxidative stress and the accumulation of oxysterols should be considered
as two key factors in cholesterol biosynthesis or metabolism disorders,
where dienyl sterol intermediates are accumulated.
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Affiliation(s)
- Libin Xu
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University , Nashville, Tennessee 37235, United States
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183
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Niki E. Biomarkers of lipid peroxidation in clinical material. Biochim Biophys Acta Gen Subj 2014; 1840:809-17. [DOI: 10.1016/j.bbagen.2013.03.020] [Citation(s) in RCA: 374] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/14/2013] [Accepted: 03/17/2013] [Indexed: 11/28/2022]
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184
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Laabei M, Jamieson WD, Massey RC, Jenkins ATA. Staphylococcus aureus interaction with phospholipid vesicles--a new method to accurately determine accessory gene regulator (agr) activity. PLoS One 2014; 9:e87270. [PMID: 24498061 PMCID: PMC3907525 DOI: 10.1371/journal.pone.0087270] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 12/27/2013] [Indexed: 11/19/2022] Open
Abstract
The staphylococcal accessory gene regulatory (agr) operon is a well-characterised global regulatory element that is important in the control of virulence gene expression for Staphylococcus aureus, a major human pathogen. Hence, accurate and sensitive measurement of Agr activity is central in understanding the virulence potential of Staphylococcus aureus, especially in the context of Agr dysfunction, which has been linked with persistent bacteraemia and reduced susceptibility to glycopeptide antibiotics. Agr function is typically measured using a synergistic haemolysis CAMP assay, which is believe to report on the level of expression of one of the translated products of the agr locus, delta toxin. In this study we develop a vesicle lysis test (VLT) that is specific to small amphipathic peptides, most notably delta and Phenol Soluble Modulin (PSM) toxins. To determine the accuracy of this VLT method in assaying Agr activity, we compared it to the CAMP assay using 89 clinical Staphylococcus aureus isolates. Of the 89 isolates, 16 were designated as having dysfunctional Agr systems by the CAMP assay, whereas only three were designated as such by VLT. Molecular analysis demonstrated that of these 16 isolates, the 13 designated as having a functional Agr system by VLT transcribed rnaIII and secreted delta toxin, demonstrating they have a functional Agr system despite the results of the CAMP assay. The agr locus of all 16 isolates was sequenced, and only the 3 designated as having a dysfunctional Agr system contained mutations, explaining their Agr dysfunction. Given the potentially important link between Agr dysfunction and clinical outcome, we have developed an assay that determines this more accurately than the conventional CAMP assay.
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Affiliation(s)
- Maisem Laabei
- Department of Chemistry, University of Bath, Claverton Down, Bath, United Kingdom
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - W. David Jamieson
- Department of Chemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Ruth C. Massey
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - A. Tobias A. Jenkins
- Department of Chemistry, University of Bath, Claverton Down, Bath, United Kingdom
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185
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Lamberson CR, Xu L, Muchalski H, Montenegro-Burke JR, Shmanai VV, Bekish AV, McLean JA, Clarke CF, Shchepinov MS, Porter NA. Unusual kinetic isotope effects of deuterium reinforced polyunsaturated fatty acids in tocopherol-mediated free radical chain oxidations. J Am Chem Soc 2014; 136:838-41. [PMID: 24380377 DOI: 10.1021/ja410569g] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Substitution of -CD2- at the reactive centers of linoleic and linolenic acids reduces the rate of abstraction of D by a tocopheryl radical by as much as 36-fold, compared to the abstraction of H from a corresponding -CH2- center. This H atom transfer reaction is the rate-determining step in the tocopherol-mediated peroxidation of lipids in human low-density lipoproteins, a process that has been linked to coronary artery disease. The unanticipated large kinetic isotope effects reported here for the tocopherol-mediated oxidation of linoleic and linolenic acids and esters suggests that tunneling makes this process favorable.
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Affiliation(s)
- Connor R Lamberson
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University , Nashville, Tennessee 37235, United States
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186
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Cheng JMH, Dangerfield EM, Timmer MSM, Stocker BL. A divergent approach to the synthesis of iGb3 sugar and lipid analogues via a lactosyl 2-azido-sphingosine intermediate. Org Biomol Chem 2014; 12:2729-36. [DOI: 10.1039/c4ob00241e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Isoglobotrihexosylceramide (iGb3, 1) is an immunomodulatory glycolipid that binds to CD1d and is presented to the T-cell receptor (TCR) of invariant natural killer T (iNKT) cells.
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Affiliation(s)
- Janice M. H. Cheng
- School of Chemical and Physical Sciences
- Victoria University of Wellington
- Wellington, New Zealand
- Malaghan Institute of Medical Research
- Wellington, New Zealand
| | - Emma M. Dangerfield
- School of Chemical and Physical Sciences
- Victoria University of Wellington
- Wellington, New Zealand
- Malaghan Institute of Medical Research
- Wellington, New Zealand
| | - Mattie S. M. Timmer
- School of Chemical and Physical Sciences
- Victoria University of Wellington
- Wellington, New Zealand
| | - Bridget L. Stocker
- School of Chemical and Physical Sciences
- Victoria University of Wellington
- Wellington, New Zealand
- Malaghan Institute of Medical Research
- Wellington, New Zealand
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187
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Daddysman MK, Tycon MA, Fecko CJ. Photoinduced damage resulting from fluorescence imaging of live cells. Methods Mol Biol 2014; 1148:1-17. [PMID: 24718791 DOI: 10.1007/978-1-4939-0470-9_1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The widespread application of fluorescence microscopy to study live cells has led to a greater understanding of numerous biological processes. Many techniques have been developed to uniquely label structures and track metabolic pathways using fluorophores in live cells. However, the photochemistry of nonnative compounds and the deposition of energy into the cell during imaging can result in unexpected and unwanted side effects. Herein, we examine potential live cell damage by first discussing common imaging considerations and modalities in fluorescence microscopy. We then consider several mechanisms by which various photochemical and photophysical phenomena cause cellular damage and introduce techniques that have leveraged these phenomena to intentionally create damage inside cells. Reviewing conditions under which intentional damage occurs can allow one to better predict when unintentional damage may be important. Finally, we delineate ways of checking for and reducing photochemical and photophysical damage.
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Affiliation(s)
- Matthew K Daddysman
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599-3290, USA
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188
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Niki E. Role of vitamin E as a lipid-soluble peroxyl radical scavenger: in vitro and in vivo evidence. Free Radic Biol Med 2014; 66:3-12. [PMID: 23557727 DOI: 10.1016/j.freeradbiomed.2013.03.022] [Citation(s) in RCA: 348] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 12/28/2022]
Abstract
Multiple reactive oxygen/nitrogen species induce oxidative stress. Mammals have evolved with an elaborate defense network against oxidative stress, in which multiple antioxidant compounds and enzymes with different functions exert their respective roles. Radical scavenging is one of the essential roles of antioxidants and vitamin E is the most abundant and important lipophilic radical-scavenging antioxidant in vivo. The kinetic data and physiological molar ratio of vitamin E to substrates show that the peroxyl radicals are the only radicals that vitamin E can scavenge to break chain propagation efficiently and that vitamin E is unable to act as a potent scavenger of hydroxyl, alkoxyl, nitrogen dioxide, and thiyl radicals in vivo. The preventive effect of vitamin E against the oxidation mediated by nonradical oxidants such as hypochlorite, singlet oxygen, ozone, and enzymes may be limited in vivo. The synergistic interaction of vitamin E and vitamin C is effective for enhancing the antioxidant capacity of vitamin E. The in vitro and in vivo evidence of the function of vitamin E as a peroxyl radical-scavenging antioxidant and inhibitor of lipid peroxidation is presented.
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Affiliation(s)
- Etsuo Niki
- Health Research Institute, National Institute of Advanced Industrial Science & Technology, Ikeda, Osaka 563-8577, Japan.
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189
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Dibrova DV, Cherepanov DA, Galperin MY, Skulachev VP, Mulkidjanian AY. Evolution of cytochrome bc complexes: from membrane-anchored dehydrogenases of ancient bacteria to triggers of apoptosis in vertebrates. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1827:1407-27. [PMID: 23871937 PMCID: PMC3839093 DOI: 10.1016/j.bbabio.2013.07.006] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 07/02/2013] [Accepted: 07/08/2013] [Indexed: 12/30/2022]
Abstract
This review traces the evolution of the cytochrome bc complexes from their early spread among prokaryotic lineages and up to the mitochondrial cytochrome bc1 complex (complex III) and its role in apoptosis. The results of phylogenomic analysis suggest that the bacterial cytochrome b6f-type complexes with short cytochromes b were the ancient form that preceded in evolution the cytochrome bc1-type complexes with long cytochromes b. The common ancestor of the b6f-type and the bc1-type complexes probably resembled the b6f-type complexes found in Heliobacteriaceae and in some Planctomycetes. Lateral transfers of cytochrome bc operons could account for the several instances of acquisition of different types of bacterial cytochrome bc complexes by archaea. The gradual oxygenation of the atmosphere could be the key evolutionary factor that has driven further divergence and spread of the cytochrome bc complexes. On the one hand, oxygen could be used as a very efficient terminal electron acceptor. On the other hand, auto-oxidation of the components of the bc complex results in the generation of reactive oxygen species (ROS), which necessitated diverse adaptations of the b6f-type and bc1-type complexes, as well as other, functionally coupled proteins. A detailed scenario of the gradual involvement of the cardiolipin-containing mitochondrial cytochrome bc1 complex into the intrinsic apoptotic pathway is proposed, where the functioning of the complex as an apoptotic trigger is viewed as a way to accelerate the elimination of the cells with irreparably damaged, ROS-producing mitochondria. This article is part of a Special Issue entitled: Respiratory complex III and related bc complexes.
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Affiliation(s)
- Daria V Dibrova
- School of Physics, University of Osnabrueck, D-49069 Osnabrueck, Germany; School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119992, Russia; Institute of Mitoengineering, Lomonosov Moscow State University, Moscow 119992, Russia
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190
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Novel kinetic method for expressing the ability of antioxidant to scavenge radicals. Chem Res Chin Univ 2013. [DOI: 10.1007/s40242-013-3140-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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191
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Oxidative modifications of conjugated and unconjugated linoleic acid during heating. Food Chem 2013; 140:680-5. [DOI: 10.1016/j.foodchem.2012.09.067] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 09/06/2012] [Accepted: 09/18/2012] [Indexed: 11/23/2022]
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192
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Oxidant-antioxidant balance in the blood of patients with chronic obstructive pulmonary disease after smoking cessation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:897075. [PMID: 24089631 PMCID: PMC3780624 DOI: 10.1155/2013/897075] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/22/2013] [Accepted: 08/07/2013] [Indexed: 01/31/2023]
Abstract
The effect of smoking cessation on the oxidative stress in patients with chronic obstructive pulmonary disease (COPD) was assessed. We recruited 73 smokers with COPD (study group), whose blood was analysed before smoking cessation, after the 1st, 2nd, and 3rd months of abstinence, 35 healthy nonsmokers (Control I), and 35 smokers with COPD (Control II). Blood was taken once in Control I and 4 times (every month) in Control II. In the study group conjugated dienes (CDs) level in plasma and erythrocytes before smoking cessation was 3 and 6.5 times higher than in Control I, respectively (P < 0.001), while thiobarbituric acid-reactive substances (TBARS) level was 89% (P < 0.001) and 51% higher (P < 0.01), respectively. Superoxide dismutase (SOD) activity was 40% higher (P < 0.05) while glutathione peroxidase (GPx) was 41% lower (P < 0.001) than in Control I. In Control II, the similar differences as compared to Control I were observed throughout the study. Smoking cessation resulted in decrease of CDs, TBARS, and SOD and GPx increase, with no changes in catalase and vitamins A and E. COPD is accompanied by oxidative stress. A three-month tobacco abstinence facilitated restoring the oxidant-antioxidant balance systemically, but it did not affect spirometric parameters.
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193
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Sultana R, Perluigi M, Butterfield DA. Lipid peroxidation triggers neurodegeneration: a redox proteomics view into the Alzheimer disease brain. Free Radic Biol Med 2013; 62:157-169. [PMID: 23044265 PMCID: PMC3573239 DOI: 10.1016/j.freeradbiomed.2012.09.027] [Citation(s) in RCA: 324] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 09/18/2012] [Accepted: 09/19/2012] [Indexed: 01/22/2023]
Abstract
Lipid peroxidation involves a cascade of reactions in which production of free radicals occurs selectively in the lipid components of cellular membranes. Polyunsaturated fatty acids easily undergo lipid peroxidation chain reactions, which, in turn, lead to the formation of highly reactive electrophilic aldehydes. Among these, the most abundant aldehydes are 4-hydroxy-2-nonenal (HNE) and malondialdehyde, while acrolein is the most reactive. Proteins are susceptible to posttranslational modifications caused by aldehydes binding covalently to specific amino acid residues, in a process called Michael adduction, and these types of protein adducts, if not efficiently removed, may be, and generally are, dangerous for cellular homeostasis. In the present review, we focused the discussion on the selective proteins that are identified, by redox proteomics, as selective targets of HNE modification during the progression and pathogenesis of Alzheimer disease (AD). By comparing results obtained at different stages of the AD, it may be possible to identify key biochemical pathways involved and ideally identify therapeutic targets to prevent, delay, or treat AD.
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Affiliation(s)
- Rukhsana Sultana
- Department of Chemistry, Center of Membrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506, USA
| | - Marzia Perluigi
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy
| | - D Allan Butterfield
- Department of Chemistry, Center of Membrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506, USA.
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194
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Yavlovich A, Viard M, Gupta K, Sine J, Vu M, Blumenthal R, Tata DB, Puri A. Low-visibility light-intensity laser-triggered release of entrapped calcein from 1,2-bis (tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine liposomes is mediated through a type I photoactivation pathway. Int J Nanomedicine 2013; 8:2575-87. [PMID: 23901274 PMCID: PMC3726434 DOI: 10.2147/ijn.s44993] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We recently reported on the physical characteristics of photo-triggerable liposomes containing dipalmitoylphosphatidylcholine (DPPC), and 1,2-bis (tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine (DC(8,9)PC) carrying a photo agent as their payload. When exposed to a low-intensity 514 nm wavelength (continuous-wave) laser light, these liposomes were observed to release entrapped calcein green (Cal-G; Ex/Em 490/517 nm) but not calcein blue (Cal-B; Ex/Em 360/460 nm). In this study, we have investigated the mechanism for the 514 nm laser-triggered release of the Cal-G payload using several scavengers that are known specifically to inhibit either type I or type II photoreaction pathways. Liposomes containing DPPC:DC(8,9)PC: distearoylphosphatidylethanolamine (DSPE)-polyethylene glycol (PEG)-2000 (86:10:04 mole ratio) were loaded either with fluorescent (calcein) or nonfluorescent ((3)H-inulin) aqueous markers. In addition, a non-photo-triggerable formulation (1-palmitoyl-2-oleoyl phosphatidylcholine [POPC]:DC(8,9)PC:DSPE-PEG2000) was also studied with the same payloads. The 514 nm wavelength laser exposure on photo-triggerable liposomes resulted in the release of Cal-G but not that of Cal-B or (3)H-inulin, suggesting an involvement of a photoactivated state of Cal-G due to the 514 nm laser exposure. Upon 514 nm laser exposures, substantial hydrogen peroxide (H2O2, ≈100 μM) levels were detected from only the Cal-G loaded photo-triggerable liposomes but not from Cal-B-loaded liposomes (≤10 μM H2O2). The Cal-G release from photo-triggerable liposomes was found to be significantly inhibited by ascorbic acid (AA), resulting in a 70%-80% reduction in Cal-G release. The extent of AA-mediated inhibition of Cal-G release from the liposomes also correlated with the consumption of AA. No AA consumption was detected in the 514 nm laser-exposed Cal B-loaded liposomes, thus confirming a role of photoactivation of Cal-G in liposome destabilization. Inclusion of 100 mM K3Fe(CN)6 (a blocker of electron transfer) in the liposomes substantially inhibited Cal-G release, whereas inclusion of 10 mM sodium azide (a blocker of singlet oxygen of type II photoreaction) in the liposomes failed to block 514 nm laser-triggered Cal-G release. Taken together, we conclude that low-intensity 514 nm laser-triggered release of Cal-G from photo-triggerable liposomes involves the type I photoreaction pathway.
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Affiliation(s)
- Amichai Yavlovich
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
| | - Mathias Viard
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
- Basic Science Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Kshitij Gupta
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
| | - Jessica Sine
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
| | - Mylinh Vu
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
| | - Robert Blumenthal
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
| | - Darrell B Tata
- Centre for Devices and Radiological Health (CDRH)/Office of Science and Engineering Laboratories(OSEL)/Division of Physics, US Food and Drug Administration, White Oak, MD, USA
| | - Anu Puri
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD, USA
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195
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Kim J, Hong VS, Lee J. Antioxidant activity of 3,4,5-trihydroxyphenylacetamide derivatives. Arch Pharm Res 2013; 37:324-31. [PMID: 23812775 DOI: 10.1007/s12272-013-0189-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 06/12/2013] [Indexed: 11/30/2022]
Abstract
A series of amide derivatives of 3,4,5-trihydroxyphenylacetic acid was synthesized in two steps. The antioxidant activities were evaluated by using four different in vitro models such as ABTS and DPPH radical scavenging activity and FTC and TBA anti-lipid peroxidation activity. Most of compounds were more powerful radical scavengers than vitamin C and were comparable to Trolox. It was found that there were no direct correlations between radical scavenging and anti-peroxidation activities. The inhibitory activity of compound on lipid peroxidation showed remarkable dependency on both the number of phenolic hydroxyl group and the length of methylene linker in N-arylalkyl group of amide. Compound 14, a conjugate of 3,4,5-trihydroxyphenylacetic acid and dopamine, was found as powerful antioxidant as propyl gallate in all four antioxidant assays.
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Affiliation(s)
- Jina Kim
- Department of Chemistry, Keimyung University, 2800 Dalgubeoldaero, Dalseo-Gu, Taegu, 704-701, Korea
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196
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Salamone M, Milan M, DiLabio GA, Bietti M. Reactions of the Cumyloxyl and Benzyloxyl Radicals with Tertiary Amides. Hydrogen Abstraction Selectivity and the Role of Specific Substrate-Radical Hydrogen Bonding. J Org Chem 2013; 78:5909-17. [DOI: 10.1021/jo400535u] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Michela Salamone
- Dipartimento di Scienze e Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1 I-00133 Rome, Italy
| | - Michela Milan
- Dipartimento di Scienze e Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1 I-00133 Rome, Italy
| | - Gino A. DiLabio
- National
Institute for Nanotechnology, National Research Council of Canada, 11421 Saskatchewan
Drive, Edmonton, Alberta, Canada T6G 2M9
- Department of Physics, University of Alberta, Edmonton, Alberta,
Canada T6G 2E1
| | - Massimo Bietti
- Dipartimento di Scienze e Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1 I-00133 Rome, Italy
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197
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Porter NA. A perspective on free radical autoxidation: the physical organic chemistry of polyunsaturated fatty acid and sterol peroxidation. J Org Chem 2013; 78:3511-24. [PMID: 23445181 PMCID: PMC3674788 DOI: 10.1021/jo4001433] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This Perspective describes advances from the author's laboratory on the free radical reactions of organic compounds with molecular oxygen. Polyunsaturated fatty acids (PUFAs) and sterols are particularly prone to undergo radical chain oxidation, and evidence suggests that this process, known as lipid peroxidation, occurs in vivo under a variety of conditions that are the result of an oxidative stress. Cyclic peroxides, hydroperoxides, and epoxy alcohols are major products formed from peroxidation, and the basic mechanisms of product formation are now reasonably well understood. These mechanisms include reversible addition of oxygen to carbon radicals, rearrangement and cyclization of allyl and pentadienyl peroxyl radicals, and homolytic substitution of carbon radicals on the peroxide bond. A physical organic approach to the problem of free radicals in biology and medicine is highlighted in this Perspective with stereochemical, kinetic, and extrathermodynamic probes applied to the study of mechanism. A radical clock permits the determination of free radical propagation rate constants, and 7-dehydrocholesterol, the immediate biosynthetic precursor of cholesterol, is found by this clock to be one of the most oxidizable lipids known. The consequences of the extreme reactivity of 7-dehydrocholesterol on human health is the focus of a current research theme in the author's laboratory.
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Affiliation(s)
- Ned A Porter
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, USA.
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198
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A density functional theory study for the role of end groups on the antioxidative potency of carotenoids. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1357-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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199
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Li B, Harjani JR, Cormier NS, Madarati H, Atkinson J, Cosa G, Pratt DA. Besting Vitamin E: Sidechain Substitution is Key to the Reactivity of Naphthyridinol Antioxidants in Lipid Bilayers. J Am Chem Soc 2013; 135:1394-405. [DOI: 10.1021/ja309153x] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bo Li
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Jitendra R. Harjani
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Nicholas S. Cormier
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Hasam Madarati
- Department of Chemistry and
Centre for Biotechnology, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Jeffrey Atkinson
- Department of Chemistry and
Centre for Biotechnology, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Gonzalo Cosa
- Department of Chemistry and Centre
for Self-Assembled Chemical Structures, McGill University, 801 Sherbrooke St. West, Montreal, Quebec H3A 0B8 Canada
| | - Derek A. Pratt
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
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200
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Firme CL, Garden SJ, de Lucas NC, Nicodem DE, Correa RJ. Theoretical Study of Photochemical Hydrogen Abstraction by Triplet Aliphatic Carbonyls by Using Density Functional Theory. J Phys Chem A 2013; 117:439-50. [DOI: 10.1021/jp307505e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Caio L. Firme
- Universidade Federal do Rio Grande do Norte, Instituto de Química,
Av. Salgado Filho, s/n, Lagoa Nova, Natal/RN, CEP 59072-970, Brazil
| | - Simon J. Garden
- Instituto de Química,
Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Centro de Tecnologia, Bloco A, Rio de Janeiro,
RJ, CEP 21949-900, Brazil
| | - Nanci C. de Lucas
- Instituto de Química,
Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Centro de Tecnologia, Bloco A, Rio de Janeiro,
RJ, CEP 21949-900, Brazil
| | - David E. Nicodem
- Instituto de Química,
Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Centro de Tecnologia, Bloco A, Rio de Janeiro,
RJ, CEP 21949-900, Brazil
| | - Rodrigo J. Correa
- Instituto de Química,
Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Centro de Tecnologia, Bloco A, Rio de Janeiro,
RJ, CEP 21949-900, Brazil
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