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Mehranfard N, Ghasemi M, Rajabian A, Ansari L. Protective potential of naringenin and its nanoformulations in redox mechanisms of injury and disease. Heliyon 2023; 9:e22820. [PMID: 38058425 PMCID: PMC10696200 DOI: 10.1016/j.heliyon.2023.e22820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 11/18/2023] [Accepted: 11/20/2023] [Indexed: 12/08/2023] Open
Abstract
Increasing evidence suggests that elevated intracellular levels of reactive oxygen species (ROS) play a significant role in the pathogenesis of many diseases. Increased intracellular levels of ROS can lead to the oxidation of lipids, DNA, and proteins, contributing to cellular damage. Hence, the maintenance of redox hemostasis is essential. Naringenin (NAR) is a flavonoid included in the flavanones subcategory. Various pharmacological actions have been ascribable to this phytochemical composition, including antioxidant, anti-inflammatory, antibacterial, antiviral, antitumor, antiadipogenic, neuro-, and cardio-protective activities. This review focused on the underlying mechanism responsible for the antioxidative stress properties of NAR and its' nanoformulations. Several lines of in vitro and in vivo investigations suggest the effects of NAR and its nanoformulation on their target cells via modulating signaling pathways. These nanoformulations include nanoemulsion, nanocarriers, solid lipid nanoparticles (SLN), and nanomicelle. This review also highlights several beneficial health effects of NAR nanoformulations on human diseases including brain disorders, cancer, rheumatoid arthritis, and small intestine injuries. Employing nanoformulation can improve the pharmacokinetic properties of NAR and consequently efficiency by reducing its limitations, such as low bioavailability. The protective effects of NAR and its' nanoformulations against oxidative stress may be linked to the modulation of Nrf2-heme oxygenase-1, NO/cGMP/potassium channel, COX-2, NF-κB, AMPK/SIRT3, PI3K/Akt/mTOR, BDNF, NOX, and LOX-1 pathways. Understanding the mechanism behind the protective effects of NAR can facilitate drug development for the treatment of oxidative stress-related disorders.
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Affiliation(s)
- Nasrin Mehranfard
- Nanokadeh Darooee Samen Private Joint Stock Company, Urmia, 5715793731, Iran
| | - Maedeh Ghasemi
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Arezoo Rajabian
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Legha Ansari
- Nanokadeh Darooee Samen Private Joint Stock Company, Urmia, 5715793731, Iran
- Cellular and Molecular Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran
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Safety Assessment of the Modified Lactoperoxidase System-In Vitro Studies on Human Gingival Fibroblasts. Int J Mol Sci 2023; 24:ijms24032640. [PMID: 36768964 PMCID: PMC9916481 DOI: 10.3390/ijms24032640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/19/2023] [Accepted: 01/27/2023] [Indexed: 02/01/2023] Open
Abstract
One strategy in caries prevention is to inhibit the formation of cariogenic biofilms. Attempts are being made to develop oral hygiene products enriched with various antimicrobial agents. One of them is lactoperoxidase-an enzyme that can oxidise (pseudo)halide ions to reactive products with antimicrobial activity. Currently, commercially available products utilise thiocyanate as a substrate; however, several alternatives that are oxidised to products with greater antimicrobial potential have been found. In this study, toxicity against human gingival fibroblasts of the lactoperoxidase system was evaluated using four different (pseudo)halide substrate systems-thiocyanate, iodide, selenocyanate, and a mixture of thiocyanate and iodide. For this purpose, cells were treated with the systems and then apoptosis, cell cycle, intracellular glutathione concentration, and mitochondrial superoxide production were assessed. The results showed that each system, after generating 250 µM of the product, inhibited cell divisions, increased apoptosis, and increased the percentage of dead cells. It was concluded that the mechanism of the observed phenomena was not related to increased superoxide production or the depletion of glutathione concentration. These findings emphasised the need for the further in vitro and in vivo toxicity investigation of the modified lactoperoxidase system to assess its safety and the possibility of use in oral hygiene products.
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Ghandhi LHD, Bidula S, Pask CM, Lord RM, McGowan PC. Bis(N-picolinamido)cobalt(II) Complexes Display Antifungal Activity toward Candida albicans and Aspergillus fumigatus. ChemMedChem 2021; 16:3210-3221. [PMID: 34327861 PMCID: PMC8597028 DOI: 10.1002/cmdc.202100159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/14/2021] [Indexed: 11/06/2022]
Abstract
This report highlights the synthesis and characterization of ten new bis(N-picolinamido)cobalt(II) complexes of the type [(L)2 CoX2 ]0/2+ , whereby L=N-picolinamide ligand and X=diisothiocyanato (-NCS), dichlorido (-Cl) or diaqua (-OH2 ) ligands. Single crystal X-ray (SC-XRD) analysis for nine of the structures are reported and confirm the picolinamide ligand is bound to the Co(II) center through a neutral N,O binding mode. With the addition of powder X-ray diffraction (PXRD), we have confirmed the cis and trans ligand arrangements of each complex. All complexes were screened against several fungal species and show increased antifungal activity. Notably, these complexes had significant activity against strains of Candida albicans and Aspergillus fumigatus, with several compounds exhibiting growth inhibition of >80 %, and onecompound inhibiting Aspergillus fumigatus hyphal growth by >90 %. Conversely, no antifungal activity was exhibited toward Cryptococcus neoformans and no cytotoxicity towards mammalian cell lines.
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Affiliation(s)
| | - Stefan Bidula
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichNR4 7JTUK
| | | | - Rianne M. Lord
- School of ChemistryUniversity of East AngliaNorwich Research ParkNorwichNR4 7JTUK
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Zhan J, Geng C, Hao X, Song W, Lin W. A near-infrared fluorescent probe for monitoring viscosity in living cells, zebrafish and mice. NEW J CHEM 2021. [DOI: 10.1039/d0nj05957a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A novel NIF fluorescent probe, ZM-V, was designed, in which interior imidazole and benzopyrene moieties serve as rotators, which can spin around multiple C–C bonds in the conjugated skeleton.
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Affiliation(s)
- Jingting Zhan
- Guangxi Key Laboratory of Electrochemical Energy Materials
- Institute of Optical Materials and Chemical Biology
- School of Chemistry and Chemical Engineering
- Guangxi University
- Nanning
| | - Chen Geng
- Guangxi Key Laboratory of Electrochemical Energy Materials
- Institute of Optical Materials and Chemical Biology
- School of Chemistry and Chemical Engineering
- Guangxi University
- Nanning
| | - Xinya Hao
- Guangxi Key Laboratory of Electrochemical Energy Materials
- Institute of Optical Materials and Chemical Biology
- School of Chemistry and Chemical Engineering
- Guangxi University
- Nanning
| | - Wenhui Song
- Guangxi Key Laboratory of Electrochemical Energy Materials
- Institute of Optical Materials and Chemical Biology
- School of Chemistry and Chemical Engineering
- Guangxi University
- Nanning
| | - Weiying Lin
- Guangxi Key Laboratory of Electrochemical Energy Materials
- Institute of Optical Materials and Chemical Biology
- School of Chemistry and Chemical Engineering
- Guangxi University
- Nanning
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Davies MJ, Hawkins CL. The Role of Myeloperoxidase in Biomolecule Modification, Chronic Inflammation, and Disease. Antioxid Redox Signal 2020; 32:957-981. [PMID: 31989833 DOI: 10.1089/ars.2020.8030] [Citation(s) in RCA: 161] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Significance: The release of myeloperoxidase (MPO) by activated leukocytes is critical in innate immune responses. MPO produces hypochlorous acid (HOCl) and other strong oxidants, which kill bacteria and other invading pathogens. However, MPO also drives the development of numerous chronic inflammatory pathologies, including atherosclerosis, neurodegenerative disease, lung disease, arthritis, cancer, and kidney disease, which are globally responsible for significant patient mortality and morbidity. Recent Advances: The development of imaging approaches to precisely identify the localization of MPO and the molecular targets of HOCl in vivo is an important advance, as typically the involvement of MPO in inflammatory disease has been inferred by its presence, together with the detection of biomarkers of HOCl, in biological fluids or diseased tissues. This will provide valuable information in regard to the cell types responsible for releasing MPO in vivo, together with new insight into potential therapeutic opportunities. Critical Issues: Although there is little doubt as to the value of MPO inhibition as a protective strategy to mitigate tissue damage during chronic inflammation in experimental models, the impact of long-term inhibition of MPO as a therapeutic strategy for human disease remains uncertain, in light of the potential effects on innate immunity. Future Directions: The development of more targeted MPO inhibitors or a treatment regimen designed to reduce MPO-associated host tissue damage without compromising pathogen killing by the innate immune system is therefore an important future direction. Similarly, a partial MPO inhibition strategy may be sufficient to maintain adequate bacterial activity while decreasing the propagation of inflammatory pathologies.
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Affiliation(s)
- Michael J Davies
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen N, Denmark
| | - Clare L Hawkins
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen N, Denmark
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Di Iorio BR, Marzocco S, Bellasi A, De Simone E, Dal Piaz F, Rocchetti MT, Cosola C, Di Micco L, Gesualdo L. Nutritional therapy reduces protein carbamylation through urea lowering in chronic kidney disease. Nephrol Dial Transplant 2019; 33:804-813. [PMID: 28992314 DOI: 10.1093/ndt/gfx203] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/28/2017] [Indexed: 11/13/2022] Open
Abstract
Background Protein carbamylation is one of the non-enzymatic reactions involved in protein molecular ageing. We sought to investigate the relationship between urea levels and protein carbamylation, and whether a Mediterranean diet (MD) and a very low protein diet (VLPD) reduce protein carbamylation through reduction in urea levels in patients with chronic kidney disease (CKD). Methods This is a prospective, randomized, crossover controlled trial that investigated 60 patients with CKD grades 3B-4 (46 males, mean age of 67 years). The enrolled CKD patients were randomly assigned (1:1) to two different nutritional treatment arms: (i) 3 months of free diet (FD), 6 months of VLPD, 3 months of FD and 6 months of MD; and (ii) 3 months of FD, 6 months of MD, 3 months of FD and 6 months of VLPD. Blood levels of lysine (Lys) and homocitrulline (Hcit) and their ratio were used as markers of cyanate levels. Due to a lack of pre-existing data on the potential effects of different dietary regimens and in light of the exploratory nature of the study, no formal sample size estimation was carried out. Results At study completion, lower diastolic blood pressure and decreased serum levels of urea, sodium, phosphorus and parathyroid hormone, but higher serum levels of bicarbonate and haemoglobin, were noted with MD and VLPD. When compared with FD, both MD and VLPD were also associated with a decrease in serum Hcit levels and Hcit/Lys ratios (P < 0.001). Notably, reductions in urea levels correlated with substantial reductions in Hcit levels (R2 = 0.16 and 0.17 for VLPD and MD, respectively). Conclusion In conclusion, nutritional treatments that significantly decrease serum levels of urea are associated with reduced protein carbamylation.
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Affiliation(s)
- Biagio R Di Iorio
- Division of Nephrology and Dialysis, 'A. Landolfi Hospital', Solofra (AV), Italy
| | - Stefania Marzocco
- Department of Pharmacology, University of Salerno, Fisciano (SA), Italy
| | - Antonio Bellasi
- Department of Nephrology and Dialysis, ASST-Lariana, Ospedale S. Anna, Como, Italy
| | - Emanuele De Simone
- Department of Nephrology and Dialysis, AORN 'San Giuseppe Moscati', Avellino, Italy
| | - Fabrizio Dal Piaz
- Department of Pharmacology, University of Salerno, Fisciano (SA), Italy
| | - Maria Teresa Rocchetti
- Division of Nephrology, Dialysis, and Transplantation, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Carmela Cosola
- Division of Nephrology, Dialysis, and Transplantation, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Lucia Di Micco
- Division of Nephrology and Dialysis, 'A. Landolfi Hospital', Solofra (AV), Italy
| | - Loreto Gesualdo
- Division of Nephrology, Dialysis, and Transplantation, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
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Mahmud SA, Binstadt BA. Autoantibodies in the Pathogenesis, Diagnosis, and Prognosis of Juvenile Idiopathic Arthritis. Front Immunol 2019; 9:3168. [PMID: 30693002 PMCID: PMC6339949 DOI: 10.3389/fimmu.2018.03168] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/24/2018] [Indexed: 12/26/2022] Open
Abstract
Autoantibody production occurs in juvenile idiopathic arthritis (JIA) and numerous other autoimmune diseases. In some conditions, the autoantibodies are clearly pathogenic, whereas in others the roles are less defined. Here we review various autoantibodies associated with JIA, with a particular focus on antinuclear antibodies and antibodies recognizing citrullinated self-antigens. We explore potential mechanisms that lead to the development of autoantibodies and the use of autoantibody testing in diagnosis and prognosis. Finally, we compare and contrast JIA-associated autoantibodies with those found in adults with rheumatoid arthritis (RA).
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Affiliation(s)
- Shawn A Mahmud
- Division of Pediatric Rheumatology, Department of Pediatrics, and the Center for Immunology, University of Minnesota, Minneapolis, MN, United States
| | - Bryce A Binstadt
- Division of Pediatric Rheumatology, Department of Pediatrics, and the Center for Immunology, University of Minnesota, Minneapolis, MN, United States
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Ahmad A, Fauzia E, Kumar M, Mishra RK, Kumar A, Khan MA, Raza SS, Khan R. Gelatin-Coated Polycaprolactone Nanoparticle-Mediated Naringenin Delivery Rescue Human Mesenchymal Stem Cells from Oxygen Glucose Deprivation-Induced Inflammatory Stress. ACS Biomater Sci Eng 2018; 5:683-695. [PMID: 33405831 DOI: 10.1021/acsbiomaterials.8b01081] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ischemic stroke involves pro-inflammatory species, which implicates inflammation in the disease mechanism. Recent studies indicate that the prevalence of therapeutic choice such as stem cell transplantation has seen an upsurge in ischemic stroke. However, after transplantation the fate of transplanted cells is largely unknown. Human mesenchymal stem cells (MSCs), due to their robust survival rate upon transplantation in brain tissue, are being widely employed to treat ischemic stroke. In the present study, we have evaluated naringenin-loaded gelatin-coated polycaprolactone nanoparticles (nar-gel-c-PCL NPs) to rescue MSCs against oxygen glucose deprived insult. Naringenin, due to its strong anti-inflammatory effects, remains a therapeutic choice in neurological disorders. Though, the low solubility and inefficient delivery remain challenges in using naringenin as a therapeutic drug. The present study showed that inflammation occurred in MSCs during their treatment with oxygen glucose deprivation (OGD) and was well overturned by treatment with nar-gel-c-PCL NPs. In brief, the results indicated that nar-gel-c-PCL NPs were able to protect the loss of cell membrane integrity and restored neuronal morphology. Then nar-gel-c-PCL NPs successfully protected the human MSCs against OGD-induced inflammation as evident by reduced level of pro-inflammatory cytokine (TNF-α, IFN-γ, and IL-1β) and other inflammatory biomarkers (COX2, iNOS, and MPO activity). Therefore, the modulation of inflammation by treatment with nar-gel-c-PCL NPs in MSCs could provide a novel strategy to improve MSC-based therapy, and thus, our nanoformulation may find a wide therapeutic application in ischemic stroke and other neuro-inflammatory diseases.
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Affiliation(s)
- Anas Ahmad
- Department of Nano-Therapeutics, Institute of Nano Science and Technology, Habitat Centre, Phase 10, Sector 64, Mohali, Punjab 160062, India
| | - Eram Fauzia
- Laboratory for Stem Cell & Restorative Neurology, Department of Biotechnology, Era's Lucknow Medical College Hospital, Sarfarazganj, Lucknow-226003, India
| | - Manish Kumar
- Laboratory for Stem Cell & Restorative Neurology, Department of Biotechnology, Era's Lucknow Medical College Hospital, Sarfarazganj, Lucknow-226003, India
| | - Rakesh Kumar Mishra
- Department of Nano-Therapeutics, Institute of Nano Science and Technology, Habitat Centre, Phase 10, Sector 64, Mohali, Punjab 160062, India
| | - Ajay Kumar
- Department of Nano-Therapeutics, Institute of Nano Science and Technology, Habitat Centre, Phase 10, Sector 64, Mohali, Punjab 160062, India
| | - Mohsin Ali Khan
- Laboratory for Stem Cell & Restorative Neurology, Department of Biotechnology, Era's Lucknow Medical College Hospital, Sarfarazganj, Lucknow-226003, India
| | - Syed Shadab Raza
- Laboratory for Stem Cell & Restorative Neurology, Department of Biotechnology, Era's Lucknow Medical College Hospital, Sarfarazganj, Lucknow-226003, India.,Department of Stem Cell Biology and Regenerative Medicine, Era's Lucknow Medical College Hospital, Sarfarazganj, Lucknow-226003, India
| | - Rehan Khan
- Department of Nano-Therapeutics, Institute of Nano Science and Technology, Habitat Centre, Phase 10, Sector 64, Mohali, Punjab 160062, India
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Dunican EM, Watchorn DC, Fahy JV. Autopsy and Imaging Studies of Mucus in Asthma. Lessons Learned about Disease Mechanisms and the Role of Mucus in Airflow Obstruction. Ann Am Thorac Soc 2018; 15:S184-S191. [PMID: 30431352 PMCID: PMC6322032 DOI: 10.1513/annalsats.201807-485aw] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 09/20/2018] [Indexed: 12/11/2022] Open
Abstract
Autopsy studies in fatal asthma have clearly documented the central role of airway plugging with pathologic mucus in the pathophysiology of death from asthma, but the role of mucus plugs in chronic severe asthma has been less well understood. Recently, multidetector computerized tomography imaging of the lungs has emerged as a valuable method to visualize mucus plugs in asthma. These multidetector computerized tomography data have revealed mucus plugs as a common occurrence in severe forms of asthma. In addition, an image-based mucus plug scoring system shows that mucus plugs are strongly associated with measures of airflow obstruction and with biomarkers of type 2 cytokine and eosinophilic inflammation. These data provide a rationale for treating airflow obstruction in severe asthma with mucolytics, and they also raise the possibility that treatments that target type 2 inflammation may decrease mucus plugs in asthma.
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Affiliation(s)
- Eleanor M Dunican
- 1 Department of Medicine, University College Dublin, Dublin, Ireland; and
| | - David C Watchorn
- 1 Department of Medicine, University College Dublin, Dublin, Ireland; and
| | - John V Fahy
- 2 Division of Pulmonary and Critical Care Medicine, Department of Medicine, and
- 3 Cardiovascular Research Institute, University of California San Francisco, San Francisco, California
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Bafort F, Damblon C, Smargiasso N, De Pauw E, Perraudin JP, Jijakli MH. Reaction Product Variability and Biological Activity of the Lactoperoxidase System Depending on Medium Ionic Strength and pH, and on Substrate Relative Concentration. Chem Biodivers 2018; 15:e1700497. [PMID: 29266741 DOI: 10.1002/cbdv.201700497] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 12/13/2017] [Indexed: 01/05/2023]
Abstract
The potential of ions produced in water by the lactoperoxidase system against plant pests has shown promising results. We tested the bioactivity of ions produced by the lactoperoxidase oxidation of I- and SCN- in several buffers or in tap water and characterized the ions produced. In vitro biological activity was tested against Penicillium expansum, the causal agent of mold in fruits, and the major cause of patulin contamination of fruit juices and compotes. In buffers, the ionic concentration was increased 3-fold, and pathogen inhibition was obtained down to the 1:15 dilution. In tap water, the ionic concentration was weaker, and pathogen inhibition was obtained only down to the 1:3 dilution. Acidic buffer increased ion concentrations as compared to less acidic (pH 5.6 or 6.2) or neutral buffers, as do increased ionic strength. 13 C-labelled SCN- and MS showed that different ions were produced in water and in buffers. In specific conditions the ion solution turned yellow and a product was formed, probably diiodothiocyanate (I2 SCN- ), giving an intense signal at 49.7 ppm in 13 C-NMR. The formation of the signal was unambiguously favored in acidic media and disadvantaged or inhibited in neutral or basic conditions. It was enhanced at a specific SCN- : I- ratio of 1:4.5, but decreased when the ratio was 1:2, and was inhibited at ratio SCN- >I- . We demonstrated that the formation of the signal required the interaction between I2 and SCN- , and MS showed the presence of I2 SCN- .
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Affiliation(s)
- Françoise Bafort
- Integrated and Urban Plant Pathology Laboratory, Gembloux Agro-Bio Tech, Liège University, Passage des Déportés 2, 5030, Gembloux, Belgium
| | - Christian Damblon
- Structural Biological Chemistry Laboratory (SBCL), Liège University, 4000, Liège, Belgium
| | - Nicolas Smargiasso
- Molecular Systems Research Unit, Mass Spectrometry Laboratory, Liège University, 4000, Liège, Belgium
| | - Edwin De Pauw
- Molecular Systems Research Unit, Mass Spectrometry Laboratory, Liège University, 4000, Liège, Belgium
| | | | - Mohamed Haïssam Jijakli
- Integrated and Urban Plant Pathology Laboratory, Gembloux Agro-Bio Tech, Liège University, Passage des Déportés 2, 5030, Gembloux, Belgium
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11
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Computational design of bio-inspired carnosine-based HOBr antioxidants. J Comput Aided Mol Des 2017; 31:905-913. [DOI: 10.1007/s10822-017-0060-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 08/31/2017] [Indexed: 01/15/2023]
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12
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Singh PK, Sirohi HV, Iqbal N, Tiwari P, Kaur P, Sharma S, Singh TP. Structure of bovine lactoperoxidase with a partially linked heme moiety at 1.98Å resolution. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:329-335. [DOI: 10.1016/j.bbapap.2016.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/05/2016] [Accepted: 12/10/2016] [Indexed: 11/26/2022]
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13
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Wang Z, DiDonato JA, Buffa J, Comhair SA, Aronica MA, Dweik RA, Lee NA, Lee JJ, Thomassen MJ, Kavuru M, Erzurum SC, Hazen SL. Eosinophil Peroxidase Catalyzed Protein Carbamylation Participates in Asthma. J Biol Chem 2016; 291:22118-22135. [PMID: 27587397 DOI: 10.1074/jbc.m116.750034] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Indexed: 12/21/2022] Open
Abstract
The biochemical mechanisms through which eosinophils contribute to asthma pathogenesis are unclear. Here we show eosinophil peroxidase (EPO), an abundant granule protein released by activated eosinophils, contributes to characteristic asthma-related phenotypes through oxidative posttranslational modification (PTM) of proteins in asthmatic airways through a process called carbamylation. Using a combination of studies we now show EPO uses plasma levels of the pseudohalide thiocyanate (SCN-) as substrate to catalyze protein carbamylation, as monitored by PTM of protein lysine residues into Nϵ-carbamyllysine (homocitrulline), and contributes to the pathophysiological sequelae of eosinophil activation. Studies using EPO-deficient mice confirm EPO serves as a major enzymatic source for protein carbamylation during eosinophilic inflammatory models, including aeroallergen challenge. Clinical studies similarly revealed significant enrichment in carbamylation of airway proteins recovered from atopic asthmatics versus healthy controls in response to segmental allergen challenge. Protein-bound homocitrulline is shown to be co-localized with EPO within human asthmatic airways. Moreover, pathophysiologically relevant levels of carbamylated protein either incubated with cultured human airway epithelial cells in vitro, or provided as an aerosolized exposure in non-sensitized mice, induced multiple asthma-associated phenotypes including induction of mucin, Th2 cytokines, IFNγ, TGFβ, and epithelial cell apoptosis. Studies with scavenger receptor-A1 null mice reveal reduced IL-13 generation following exposure to aerosolized carbamylated protein, but no changes in other asthma-related phenotypes. In summary, EPO-mediated protein carbamylation is promoted during allergen-induced asthma exacerbation, and can both modulate immune responses and trigger a cascade of many of the inflammatory signals present in asthma.
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Affiliation(s)
- Zeneng Wang
- From the Departments of Cellular and Molecular Medicine
| | | | | | | | | | | | - Nancy A Lee
- the Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona 85259
| | - James J Lee
- the Department of Biochemistry and Molecular Biology, Mayo Clinic, Scottsdale, Arizona 85259
| | - Mary Jane Thomassen
- the Division of Pulmonary, Critical Care & Sleep Medicine, East Carolina University, Greenville, North Carolina 27834, and
| | - Mani Kavuru
- the Division of Pulmonary and Critical Care Medicine, Thomas Jefferson University and Hospital, Philadelphia, Pennsylvania 19107
| | | | - Stanley L Hazen
- From the Departments of Cellular and Molecular Medicine, Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio 44195,
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Toxicity of eosinophil MBP is repressed by intracellular crystallization and promoted by extracellular aggregation. Mol Cell 2015; 57:1011-1021. [PMID: 25728769 PMCID: PMC4904734 DOI: 10.1016/j.molcel.2015.01.026] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 12/29/2014] [Accepted: 01/20/2015] [Indexed: 01/07/2023]
Abstract
Eosinophils are white blood cells that function in innate immunity and participate in the pathogenesis of various inflammatory and neoplastic disorders. Their secretory granules contain four cytotoxic proteins, including the eosinophil major basic protein (MBP-1). How MBP-1 toxicity is controlled within the eosinophil itself and activated upon extracellular release is unknown. Here we show how intragranular MBP-1 nanocrystals restrain toxicity, enabling its safe storage, and characterize them with an X-ray-free electron laser. Following eosinophil activation, MBP-1 toxicity is triggered by granule acidification, followed by extracellular aggregation, which mediates the damage to pathogens and host cells. Larger non-toxic amyloid plaques are also present in tissues of eosinophilic patients in a feedback mechanism that likely limits tissue damage under pathological conditions of MBP-1 oversecretion. Our results suggest that MBP-1 aggregation is important for innate immunity and immunopathology mediated by eosinophils and clarify how its polymorphic self-association pathways regulate toxicity intra- and extracellularly.
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15
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Chandler JD, Day BJ. Biochemical mechanisms and therapeutic potential of pseudohalide thiocyanate in human health. Free Radic Res 2015; 49:695-710. [PMID: 25564094 DOI: 10.3109/10715762.2014.1003372] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Thiocyanate (SCN(-)) is a ubiquitous molecule in mammalian biology, reaching up to mM concentrations in extracellular fluids. Two- electron oxidation of SCN(-) by H2O2 produces hypothiocyanous acid (HOSCN), a potent anti-microbial species. This reaction is catalyzed by chordate peroxidases (e.g., myeloperoxidase and lactoperoxidase), occurring in human secretory mucosa, including the oral cavity, airway, and alimentary tract, and regulates resident and transient flora as part of innate immunity. Increasing SCN(-) levels limits the concentrations of a family of 2-electron oxidants (H2O2, hypohalous acids, and haloamines) in favor of HOSCN formation, altering the oxidative impact on host tissue by substitution of repairable thiol and selenol oxidations instead of biomolecule degradation. This fine-tuning of inflammatory oxidation paradoxically associates with maintained host defense and decreased host injury during infections, due in part to phylogenetic differences in the thioredoxin reductase system between mammals and their pathogens. These differences could be exploited by pharmacologic use of SCN(-). Recent preclinical studies have identified anti-microbial and anti-inflammatory effects of SCN(-) in pulmonary and cardiovascular animal models, with implications for treatment of infectious lung disease and atherogenesis. Further research is merited to expand on these findings and identify other diseases where SCN(-) may be of use. High oral bioavailability and an increased knowledge of the biochemical effects of SCN(-) on a subset of pro-inflammatory reactions suggest clinical utility.
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Hajishengallis G, Russell MW. Innate Humoral Defense Factors. Mucosal Immunol 2015. [PMCID: PMC7149745 DOI: 10.1016/b978-0-12-415847-4.00015-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although innate immunity came into the research spotlight in the late 1990s when its instructive role in the adaptive immune response was recognized, innate humoral defense factors have a much older history. The exocrine secretions of the body contain a plethora of distinct soluble factors (lysozyme, lactoferrin, peroxidases, proline-rich proteins, histatins, etc.) that protect the body from mucosal microbial pathogens. More recent studies have established that the humoral arm of innate immunity contains a heterogeneous group of pattern-recognition molecules (e.g., pentraxins, collectins, and ficolins), which perform diverse host-defense functions, such as agglutination and neutralization, opsonization, control of inflammation, and complement activation and regulation. These pattern-recognition molecules, which act as functional predecessors of antibodies (“ante-antibodies”), and the classic soluble innate defense factors form an integrated system with complementary specificity, action, and tissue distribution, and they are the subject of this chapter.
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Bafort F, Parisi O, Perraudin JP, Jijakli MH. Mode of action of lactoperoxidase as related to its antimicrobial activity: a review. Enzyme Res 2014; 2014:517164. [PMID: 25309750 PMCID: PMC4182067 DOI: 10.1155/2014/517164] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/19/2014] [Accepted: 08/19/2014] [Indexed: 01/11/2023] Open
Abstract
Lactoperoxidase is a member of the family of the mammalian heme peroxidases which have a broad spectrum of activity. Their best known effect is their antimicrobial activity that arouses much interest in in vivo and in vitro applications. In this context, the proper use of lactoperoxidase needs a good understanding of its mode of action, of the factors that favor or limit its activity, and of the features and properties of the active molecules. The first part of this review describes briefly the classification of mammalian peroxidases and their role in the human immune system and in host cell damage. The second part summarizes present knowledge on the mode of action of lactoperoxidase, with special focus on the characteristics to be taken into account for in vitro or in vivo antimicrobial use. The last part looks upon the characteristics of the active molecule produced by lactoperoxidase in the presence of thiocyanate and/or iodide with implication(s) on its antimicrobial activity.
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Affiliation(s)
- F. Bafort
- Plant Pathology Laboratory, Liége University, Gembloux Agro-Bio Tech, Passage des Déportés 2, 5030 Gembloux, Belgium
| | - O. Parisi
- Plant Pathology Laboratory, Liége University, Gembloux Agro-Bio Tech, Passage des Déportés 2, 5030 Gembloux, Belgium
| | - J.-P. Perraudin
- Taradon Laboratory, Avenue Léon Champagne 2, 1480 Tubize, Belgium
| | - M. H. Jijakli
- Plant Pathology Laboratory, Liége University, Gembloux Agro-Bio Tech, Passage des Déportés 2, 5030 Gembloux, Belgium
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Bonifay V, Barrett TJ, Pattison DI, Davies MJ, Hawkins CL, Ashby MT. Tryptophan oxidation in proteins exposed to thiocyanate-derived oxidants. Arch Biochem Biophys 2014; 564:1-11. [PMID: 25172223 DOI: 10.1016/j.abb.2014.08.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/02/2014] [Accepted: 08/18/2014] [Indexed: 01/15/2023]
Abstract
Human defensive peroxidases, including lactoperoxidase (LPO) and myeloperoxidase (MPO), are capable of catalyzing the oxidation of halides (X(-)) by H2O2 to give hypohalous acids (HOX) for the purpose of cellular defense. Substrate selectivity depends upon the relative abundance of the halides, but the pseudo-halide thiocyanate (SCN(-)) is a major substrate, and sometimes the exclusive substrate, of all defensive peroxidases in most physiologic fluids. The resulting hypothiocyanous acid (HOSCN) has been implicated in cellular damage via thiol oxidation. While thiols are believed to be the primary target of HOSCN in vivo, Trp residues have also been implicated as targets for HOSCN. However, the mechanism involved in HOSCN-mediated Trp oxidation was not established. Trp residues in proteins appeared to be susceptible to oxidation by HOSCN, whereas free Trp and Trp residues in small peptides were found to be unreactive. We show that HOSCN-induced Trp oxidation is dependent on pH, with oxidation of free Trp, and Trp-containing peptides observed when the pH is below 2. These conditions mimic those employed previously to precipitate proteins after treatment with HOSCN, which accounts for the discrepancy in the results reported for proteins versus free Trp and small peptides. The reactant in these cases may be thiocyanogen ((SCN)2), which is produced by comproportionation of HOSCN and SCN(-) at low pH. Reaction of thiocyanate-derived oxidants with protein Trp residues at low pH results in the formation of a number of oxidation products, including mono- and di-oxygenated derivatives, which are also formed with other hypohalous acids. Our data suggest that significant modification of Trp by HOSCN in vivo is likely to have limited biological relevance.
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Affiliation(s)
- Vincent Bonifay
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
| | - Tessa J Barrett
- Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - David I Pattison
- Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Michael J Davies
- Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Clare L Hawkins
- Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Michael T Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA.
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Kajer TB, Fairfull-Smith KE, Yamasaki T, Yamada KI, Fu S, Bottle SE, Hawkins CL, Davies MJ. Inhibition of myeloperoxidase- and neutrophil-mediated oxidant production by tetraethyl and tetramethyl nitroxides. Free Radic Biol Med 2014; 70:96-105. [PMID: 24566469 DOI: 10.1016/j.freeradbiomed.2014.02.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/23/2014] [Accepted: 02/12/2014] [Indexed: 12/17/2022]
Abstract
The powerful oxidant HOCl (hypochlorous acid and its corresponding anion, (-)OCl) generated by the myeloperoxidase (MPO)-H2O2-Cl(-) system of activated leukocytes is strongly associated with multiple human inflammatory diseases; consequently there is considerable interest in inhibition of this enzyme. Nitroxides are established antioxidants of low toxicity that can attenuate oxidation in animal models, with this ascribed to superoxide dismutase or radical-scavenging activities. We have shown (M.D. Rees et al., Biochem. J. 421, 79-86, 2009) that nitroxides, including 4-amino-TEMPO (4-amino-2,2,6,6-tetramethylpiperidin-1-yloxyl radical), are potent inhibitors of HOCl formation by isolated MPO and activated neutrophils, with IC50 values of ~1 and ~6 µM respectively. The utility of tetramethyl-substituted nitroxides is, however, limited by their rapid reduction by biological reductants. The corresponding tetraethyl-substituted nitroxides have, however, been reported to be less susceptible to reduction. In this study we show that the tetraethyl species were reduced less rapidly than the tetramethyl species by both human plasma (89-99% decreased rate of reduction) and activated human neutrophils (62-75% decreased rate). The tetraethyl-substituted nitroxides retained their ability to inhibit HOCl production by MPO and activated neutrophils with IC50 values in the low-micromolar range; in some cases inhibition was enhanced compared to tetramethyl substitution. Nitroxides with rigid structures (fused oxaspiro rings) were, however, inactive. Overall, these data indicate that tetraethyl-substituted nitroxides are potent inhibitors of oxidant formation by MPO, with longer plasma and cellular half-lives compared to the tetramethyl species, potentially allowing lower doses to be employed.
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Affiliation(s)
- Tracey B Kajer
- Heart Research Institute, Newtown, Sydney, NSW 2042, Australia; Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Kathryn E Fairfull-Smith
- School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Toshihide Yamasaki
- Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Kyushu, Japan
| | - Ken-ichi Yamada
- Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Kyushu, Japan
| | - Shanlin Fu
- Centre for Forensic Science, University of Technology, Sydney, NSW, Australia
| | - Steven E Bottle
- School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Clare L Hawkins
- Heart Research Institute, Newtown, Sydney, NSW 2042, Australia; Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Michael J Davies
- Heart Research Institute, Newtown, Sydney, NSW 2042, Australia; Faculty of Medicine, University of Sydney, Sydney, NSW, Australia.
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20
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Li H, Cao Z, Zhang G, Thannickal VJ, Cheng G. Vascular peroxidase 1 catalyzes the formation of hypohalous acids: characterization of its substrate specificity and enzymatic properties. Free Radic Biol Med 2012; 53:1954-9. [PMID: 22982576 PMCID: PMC3506185 DOI: 10.1016/j.freeradbiomed.2012.08.597] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 02/07/2023]
Abstract
The heme-containing peroxidase family comprises eight members in humans. The physiological and pathophysiological roles of heme-containing peroxidases are not well understood. Phagocyte-derived myeloperoxidase (MPO) utilizes chloride and bromide, in the presence of hydrogen peroxide (H(2)O(2)), to generate hypochlorous acid and hypobromous acid, potent oxidizing species that are known to kill invading pathogens. Vascular peroxidase 1 (VPO1) is a new member of the heme-containing peroxidase family; VPO1 is highly expressed in the cardiovascular system, lung, liver, pancreas, and spleen. However, functional roles of VPO1 have not been defined. In this report, we demonstrate the capacity for VPO1 to catalyze the formation of hypohalous acids, and characterize its enzymatic properties. VPO1, like MPO but unlike lactoperoxidase, is able to generate hypochlorous acid, hypobromous acid, and hypothiocyanous acid in the presence of H(2)O(2). Under physiological pH and concentrations of halides (100μM KBr, 100μM KSCN, and 100mM NaCl), VPO1 utilizes approximately 45% of H(2)O(2) for the generation of hypobromous acid, 35% for hypothiocyanous acid, and 18% for hypochlorous acid. The specific activity of VPO1 is ∼10- to 70-fold lower than that of MPO, depending on the specific substrate. These studies demonstrate that the enzymatic properties and substrate specificity of VPO1 are similar to MPO; however, significantly lower catalytic rate constants of VPO1 relative to MPO suggest the possibility of other physiologic roles for this novel heme-containing peroxidase.
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Affiliation(s)
- Hong Li
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Zehong Cao
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Guogang Zhang
- Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha, China 410008
| | - Victor J. Thannickal
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Guangjie Cheng
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Barrett TJ, Pattison DI, Leonard SE, Carroll KS, Davies MJ, Hawkins CL. Inactivation of thiol-dependent enzymes by hypothiocyanous acid: role of sulfenyl thiocyanate and sulfenic acid intermediates. Free Radic Biol Med 2012; 52:1075-85. [PMID: 22248862 PMCID: PMC3523338 DOI: 10.1016/j.freeradbiomed.2011.12.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 12/20/2011] [Accepted: 12/21/2011] [Indexed: 01/06/2023]
Abstract
Myeloperoxidase (MPO) forms reactive oxidants including hypochlorous and hypothiocyanous acids (HOCl and HOSCN) under inflammatory conditions. HOCl causes extensive tissue damage and plays a role in the progression of many inflammatory-based diseases. Although HOSCN is a major MPO oxidant, particularly in smokers, who have elevated plasma thiocyanate, the role of this oxidant in disease is poorly characterized. HOSCN induces cellular damage by targeting thiols. However, the specific targets and mechanisms involved in this process are not well defined. We show that exposure of macrophages to HOSCN results in the inactivation of intracellular enzymes, including creatine kinase (CK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In each case, the active-site thiol residue is particularly sensitive to oxidation, with evidence for reversible inactivation and the formation of sulfenyl thiocyanate and sulfenic acid intermediates, on treatment with HOSCN (less than fivefold molar excess). Experiments with DAz-2, a cell-permeable chemical trap for sulfenic acids, demonstrate that these intermediates are formed on many cellular proteins, including GAPDH and CK, in macrophages exposed to HOSCN. This is the first direct evidence for the formation of protein sulfenic acids in HOSCN-treated cells and highlights the potential of this oxidant to perturb redox signaling processes.
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Affiliation(s)
- Tessa J. Barrett
- The Heart Research Institute, Newtown, NSW 2042, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - David I. Pattison
- The Heart Research Institute, Newtown, NSW 2042, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Stephen E. Leonard
- Chemical Biology Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kate S. Carroll
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Michael J. Davies
- The Heart Research Institute, Newtown, NSW 2042, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Clare L. Hawkins
- The Heart Research Institute, Newtown, NSW 2042, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
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23
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Abstract
Hypothiocyanous acid (HOSCN) is produced in biological systems by the peroxidase-catalyzed reaction of thiocyanate (SCN(-)) with H(2)O(2). This oxidant plays an important role in the human immune system, owing to its potent bacteriostatic properties. Significant amounts of HOSCN are also formed by immune cells under inflammatory conditions, yet the reactivity of this oxidant with host tissue is poorly characterized. Traditionally, HOSCN has been viewed as a mild oxidant, which is innocuous to mammalian cells. Indeed, recent studies show that the presence of SCN(-) in airways has a protective function, by preventing the formation of other, more damaging, inflammatory oxidants. However, there is an increasing body of evidence that challenges this dogma, showing that the selectivity of HOSCN for specific thiol-containing cellular targets results in the initiation of significant cellular damage. This propensity to induce cellular dysfunction is gaining considerable interest, particularly in the cardiovascular field, as smokers have elevated plasma SCN(-), the precursor for HOSCN. This review will outline the beneficial and detrimental aspects of HOSCN formation in biological systems.
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Affiliation(s)
- Tessa J Barrett
- Inflammation Group, The Heart Research Institute , 7 Eliza Street, Newtown, Sydney, NSW 2042, Australia
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Kalmár J, Woldegiorgis KL, Biri B, Ashby MT. Mechanism of Decomposition of the Human Defense Factor Hypothiocyanite Near Physiological pH. J Am Chem Soc 2011; 133:19911-21. [DOI: 10.1021/ja2083152] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- József Kalmár
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Kelemu L. Woldegiorgis
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Bernadett Biri
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Michael T. Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
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Jaisson S, Pietrement C, Gillery P. Carbamylation-derived products: bioactive compounds and potential biomarkers in chronic renal failure and atherosclerosis. Clin Chem 2011; 57:1499-505. [PMID: 21768218 DOI: 10.1373/clinchem.2011.163188] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Carbamylation is a posttranslational modification of proteins resulting from the nonenzymatic reaction between isocyanic acid and specific free functional groups. This reaction alters protein structural and functional properties and thus contributes to molecular ageing. Many studies have shown the involvement of carbamylated proteins in diseases, especially in chronic renal failure and atherosclerosis. CONTENT In this review we describe the biochemical basis of the carbamylation process and its role in protein molecular ageing. We summarize the current evidence of protein carbamylation involvement in disease, identify available biomarkers of the carbamylation process and their related analytical methods, and discuss the practical relevance of these biomarkers. SUMMARY Carbamylation-induced protein alterations are involved in the progression of various diseases, because carbamylation-derived products (CDPs) are bioactive compounds that trigger specific and inappropriate cellular responses. For instance, carbamylation may promote hormone and enzyme inactivation, and carbamylated proteins, as diverse as collagen or LDLs, induce characteristic biochemical events of atherosclerosis progression. CDPs are potential biomarkers to monitor diseases characterized by an increased rate of carbamylation (e.g., chronic renal failure and atherosclerosis). Different methods (e.g., liquid chromatography-tandem mass spectrometry and immunoassays) to measure specific carbamylated proteins or general markers of carbamylation, such as protein-bound homocitrulline, have been described. Their use in clinical practice must still be validated by appropriate clinical studies.
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Affiliation(s)
- Stéphane Jaisson
- Laboratory of Pediatric Biology and Research, American Memorial Hospital, University Hospital of Reims,France.
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Madhusudhana Rao A, Anand U, Anand CV. Myeloperoxidase in chronic kidney disease. Indian J Clin Biochem 2011; 26:28-31. [PMID: 22211010 PMCID: PMC3068762 DOI: 10.1007/s12291-010-0075-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 06/10/2010] [Indexed: 01/08/2023]
Abstract
Numerous lines of evidence implicate a role of myeloperoxidase (MPO) in the pathogenesis of cardiovascular disease (CVD). It is a well accepted fact that patients with chronic kidney disease (CKD) are at an increased risk for CVD. MPO is a pro-oxidant enzyme which could be involved in the increased susceptibility of these patients to CVD. Hence, the levels of plasma MPO was determined in healthy controls as well as in patients with CKD [stratified with the level of their kidney failure as CKD stages II-V (end stage renal disease)]. Plasma MPO was assayed by a spectrophotometric method. Serum urea and creatinine were estimated on a clinical chemistry analyzer using standard laboratory procedures. The mean plasma MPO levels were significantly lower with advancing stages of renal failure (P < 0.001). There was a positive correlation between MPO and GFR (r = +0.89, P < 0.001) and a negative correlation with urea (r = -0.85, P < 0.001) and creatinine (r = -0.82, P < 0.001). While an inverse association was observed between plasma MPO and urea in CKD patients, such an association was not observed in control subjects (P = 0.43). In conclusion, the decline in plasma MPO levels may be due to the inhibitory effect of uraemic toxins on the enzyme.
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Affiliation(s)
- A. Madhusudhana Rao
- Department of Biochemistry, PSG Institute of Medical Sciences and Research, Coimbatore, 641004 Tamil Nadu India
| | - Usha Anand
- Department of Biochemistry, PSG Institute of Medical Sciences and Research, Coimbatore, 641004 Tamil Nadu India
| | - C. V. Anand
- Department of Biochemistry, PSG Institute of Medical Sciences and Research, Coimbatore, 641004 Tamil Nadu India
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Ranguelova K, Chatterjee S, Ehrenshaft M, Ramirez DC, Summers FA, Kadiiska MB, Mason RP. Protein Radical Formation Resulting from Eosinophil Peroxidase-catalyzed Oxidation of Sulfite. J Biol Chem 2010; 285:24195-205. [PMID: 20501663 DOI: 10.1074/jbc.m109.069054] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eosinophil peroxidase (EPO) is an abundant heme protein in eosinophils that catalyzes the formation of cytotoxic oxidants implicated in asthma, allergic inflammatory disorders, and cancer. It is known that some proteins with peroxidase activity (horseradish peroxidase and prostaglandin hydroperoxidase) can catalyze oxidation of bisulfite (hydrated sulfur dioxide), leading to the formation of sulfur trioxide anion radical ((.)SO(3)(-)). This free radical further reacts with oxygen to form peroxymonosulfate anion radical ((-)O(3)SOO(.)) and the very reactive sulfate anion radical (SO(4)()), which is nearly as strong an oxidant as the hydroxyl radical. However, the ability of EPO to generate reactive sulfur radicals has not yet been reported. Here we demonstrate that eosinophil peroxidase/H(2)O(2) is able to oxidize bisulfite, ultimately forming the sulfate anion radical (SO(4)()), and that these reactive intermediates can oxidize target proteins to protein radicals, thereby initiating protein oxidation. We used immuno-spin trapping and confocal microscopy to study protein oxidation by EPO/H(2)O(2) in the presence of bisulfite in a pure enzymatic system and in human promyelocytic leukemia HL-60 clone 15 cells, maturated to eosinophils. Polyclonal antiserum raised against the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) detected the presence of DMPO covalently attached to the proteins resulting from the DMPO trapping of protein free radicals. We found that sulfite oxidation mediated by EPO/H(2)O(2) induced the formation of radical-derived DMPO spin-trapped human serum albumin and, to a lesser extent, of DMPO-EPO. These studies suggest that EPO-dependent oxidative damage may play a role in tissue injury in bisulfite-exacerbated eosinophilic inflammatory disorders.
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Affiliation(s)
- Kalina Ranguelova
- Laboratory of Pharmacology, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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Abstract
Hypohalous acids (HOX), produced by peroxidase-catalysed reactions of halide and pseudohalide ions with H(2)O(2), play an important role in the human immune system. However, there is compelling evidence that these oxidants also mediate host tissue damage and contribute to the progression of a number of inflammatory diseases. Although it is well established that significant amounts of hypothiocyanous acid (HOSCN) are formed under physiological conditions, the reactions of this oxidant with host biological systems are relatively poorly characterized. It is generally accepted that HOSCN is a mild oxidant that reacts selectively with thiols. However, it is becoming increasingly recognized that this selectivity can result in the induction of significant cellular damage, which may contribute to disease. This review will outline the formation and reactivity of HOSCN and the role of this oxidant in biological systems.
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Affiliation(s)
- Clare L Hawkins
- Inflammation Group, The Heart Research Institute, 7 Eliza Street, Newtown, Sydney, NSW 2042, Australia.
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29
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Lemma K, Ashby MT. Reactive Sulfur Species: Kinetics and Mechanism of the Reaction of Hypothiocyanous Acid with Cyanide To Give Dicyanosulfide in Aqueous Solution. Chem Res Toxicol 2009; 22:1622-8. [DOI: 10.1021/tx900212r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kelemu Lemma
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - Michael T. Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
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30
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Wagner BA, Reszka KJ, McCormick ML, Britigan BE, Evig CB, Burns CP. Role of Thiocyanate, Bromide and Hypobromous Acid in Hydrogen Peroxide-induced Apoptosis. Free Radic Res 2009; 38:167-75. [PMID: 15104210 DOI: 10.1080/10715760310001643302] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We have previously reported that H2O2-induced apoptosis in HL-60 human leukemia cells takes place in the presence of chloride, requires myeloperoxidase (MPO), and occurs through oxidative reactions involving hypochlorous acid and chloramines. We now report that when chloride is replaced by the pseudohalide thiocyanate, there is little or no H2O2-induced apoptosis. Furthermore, thiocyanate inhibits H2O2-induced apoptosis when chloride is present at physiological concentrations, and this occurs at thiocyanate concentrations that are present in human serum and saliva. In contrast, bromide can substitute for chloride in H2O2-induced apoptosis, but results in a lower percent of the cells induced into apoptosis. Hypobromous acid is likely a short-lived intermediate in this H2O2/MPO/bromide apoptosis, and reagent hypobromous acid and bromamines induce apoptosis in HL-60 cells. We conclude that the physiologic concentrations of thiocyanate found in human plasma could modulate the cytototoxicity of H2O2 and its resulting highly toxic MPO-generated hypochlorous acid by competing with chloride for MPO. Furthermore, the oxidative products of the reaction of thiocyanate with MPO are relatively innocuous for human leukemic cells in culture. In contrast, bromide can support H2O2/MPO/halide apoptosis, but is less potent than chloride and it has no effect in the presence of physiological levels of chloride.
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Affiliation(s)
- Brett A Wagner
- Department of Medicine, Free Radical and Radiation Biology Graduate Program, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
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Gross S, Gammon ST, Moss BL, Rauch D, Harding J, Heinecke JW, Ratner L, Piwnica-Worms D. Bioluminescence imaging of myeloperoxidase activity in vivo. Nat Med 2009; 15:455-61. [PMID: 19305414 PMCID: PMC2831476 DOI: 10.1038/nm.1886] [Citation(s) in RCA: 259] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Accepted: 10/18/2008] [Indexed: 12/17/2022]
Abstract
The myeloperoxidase (MPO) system of activated phagocytes is central to normal host defense mechanisms, and dysregulated MPO contributes to the pathogenesis of inflammatory disease states ranging from atherosclerosis to cancer. Here we show that upon systemic administration, the small molecule luminol enables noninvasive bioluminescence imaging (BLI) of MPO activity in vivo. Luminol-BLI allowed quantitative longitudinal monitoring of MPO activity in animal models of acute dermatitis, mixed allergic contact hypersensitivity, focal arthritis and spontaneous large granular lymphocytic tumors. Bioluminescence colocalized with histological sites of inflammation and was totally abolished in gene-deleted Mpo(-/-) mice, despite massive tissue infiltration of neutrophils and activated eosinophils, indicating that eosinophil peroxidase did not contribute to luminol-BLI in vivo. Thus, luminol-BLI provides a noninvasive, specific and highly sensitive optical readout of phagocyte-mediated MPO activity in vivo and may enable new diagnostic applications in a wide range of acute and chronic inflammatory conditions.
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Affiliation(s)
- Shimon Gross
- Molecular Imaging Center, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
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Tryptophan residues are targets in hypothiocyanous acid-mediated protein oxidation. Biochem J 2008; 416:441-52. [DOI: 10.1042/bj20070941] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Myeloperoxidase, released by activated phagocytes, forms reactive oxidants by catalysing the reaction of halide and pseudo-halide ions with H2O2. These oxidants have been linked to tissue damage in a range of inflammatory diseases. With physiological levels of halide and pseudo-halide ions, similar amounts of HOCl (hypochlorous acid) and HOSCN (hypothiocyanous acid) are produced by myeloperoxidase. Although the importance of HOSCN in initiating cellular damage via thiol oxidation is becoming increasingly recognized, there are limited data on the reactions of HOSCN with other targets. In the present study, the products of the reaction of HOSCN with proteins has been studied. With albumin, thiols are oxidized preferentially forming unstable sulfenyl thiocyanate derivatives, as evidenced by the reversible incorporation of 14C from HOS14CN. On consumption of the HSA (human serum albumin) free thiol group, the formation of stable 14C-containing products and oxidation of tryptophan residues are observed. Oxidation of tryptophan residues is observed on reaction of HOSCN with other proteins (including myoglobin, lysozyme and trypsin inhibitor), but not free tryptophan, or tryptophan-containing peptides. Peptide mass mapping studies with HOSCN-treated myoglobin, showed the addition of two oxygen atoms on either Trp7 or Trp14 with equimolar or less oxidant, and the addition of a further two oxygen atoms to the other tryptophan with higher oxidant concentrations (≥2-fold). Tryptophan oxidation was observed on treating myoglobin with HOSCN in the presence of glutathione and ascorbate. Thus tryptophan residues are likely to be favourable targets for the reaction in biological systems, and the oxidation products formed may be useful biomarkers of HOSCN-mediated protein oxidation.
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Hypothiocyanous acid is a more potent inducer of apoptosis and protein thiol depletion in murine macrophage cells than hypochlorous acid or hypobromous acid. Biochem J 2008; 414:271-80. [PMID: 18459943 DOI: 10.1042/bj20080468] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hypohalous acids are generated by activated leucocytes, via the formation of H(2)O(2) and the release of peroxidase enzymes (myeloperoxidase and eosinophil peroxidase). These species are important bactericidal agents, but HOCl (hypochlorous acid) and HOBr (hypobromous acid) have also been implicated in tissue damage in a number of inflammatory diseases. HOSCN (hypothiocyanous acid; cyanosulfenic acid) is a milder, more thiol-specific, oxidant than HOCl or HOBr and as such may be a more potent inducer of cellular dysfunction due to selective targeting of critical thiol residues on proteins. In the present study, HOCl and HOBr are shown to react rapidly with macrophage (J774A.1) cells, resulting in a greater extent of cell lysis compared with HOSCN. However, HOSCN induces apoptosis and necrosis with greater efficacy, and at lower concentrations, than HOCl or HOBr. Apoptosis occurs in conjunction with an increased release of cytochrome c into the cytosol, but no associated increase in caspase activity. Similarly, apoptosis is observed on treating the cells in the presence of a caspase inhibitor, suggesting that it is mediated by a caspase-independent pathway. HOSCN oxidized protein thiols more efficiently than either HOCl or HOBr. The greater efficacy of HOSCN in inducing apoptosis is attributed to selective damage to critical mitochondrial membrane protein thiol groups, resulting in increased permeability and subsequent leakage of cytochrome c into the cytosol. This induction of damage by HOSCN may be of critical importance in people with elevated levels of SCN(-) (thiocyanate ions) arising from cigarette smoking, and plays a role in the pathologies associated with this biological insult.
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Winterbourn CC, Hampton MB. Thiol chemistry and specificity in redox signaling. Free Radic Biol Med 2008; 45:549-61. [PMID: 18544350 DOI: 10.1016/j.freeradbiomed.2008.05.004] [Citation(s) in RCA: 889] [Impact Index Per Article: 55.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Revised: 05/02/2008] [Accepted: 05/06/2008] [Indexed: 12/16/2022]
Abstract
Exposure of cells to sublethal oxidative stress results in the modulation of various signaling pathways. Oxidants can activate and inactivate transcription factors, membrane channels, and metabolic enzymes, and regulate calcium-dependent and phosphorylation signaling pathways. Oxidation and reduction of thiol proteins are thought to be the major mechanisms by which reactive oxidants integrate into cellular signal transduction pathways. This review focuses on mechanisms for sensing and transmitting redox signals, from the perspective of their chemical reactivity with specific oxidants. We discuss substrate preferences for different oxidants and how the kinetics of these reactions determines how each oxidant will react in a cell. This kinetic approach helps to identify initial oxidant-sensitive targets and elucidate mechanisms involved in transmission of redox signals. It indicates that only those proteins with very high reactivity, such as peroxiredoxins, are likely to be direct targets for hydrogen peroxide. Other more modestly reactive thiol proteins such as protein tyrosine phosphatases are more likely to become oxidized by an indirect mechanism. The review also examines oxidative changes observed during receptor-mediated signaling, the strengths and limitations of detection methods for reactive oxidant production, and the evidence for hydrogen peroxide acting as the second messenger. We discuss areas where observations in cell systems can be rationalized with the reactivity of specific oxidants and where further work is needed to understand the mechanisms involved.
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Affiliation(s)
- Christine C Winterbourn
- Free Radical Research Group and the National Research Centre for Growth and Development, Department of Pathology, University of Otago, Christchurch, New Zealand.
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Davies MJ, Hawkins CL, Pattison DI, Rees MD. Mammalian heme peroxidases: from molecular mechanisms to health implications. Antioxid Redox Signal 2008; 10:1199-234. [PMID: 18331199 DOI: 10.1089/ars.2007.1927] [Citation(s) in RCA: 423] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A marked increase in interest has occurred over the last few years in the role that mammalian heme peroxidase enzymes, primarily myeloperoxidase, eosinophil peroxidase, and lactoperoxidase, may play in both disease prevention and human pathologies. This increased interest has been sparked by developments in our understanding of polymorphisms that control the levels of these enzymes, a greater understanding of the basic chemistry and biochemistry of the oxidants formed by these species, the development of specific biomarkers that can be used in vivo to detect damage induced by these oxidants, the detection of active forms of these peroxidases at most, if not all, sites of inflammation, and a correlation between the levels of these enzymes and a number of major human pathologies. This article reviews recent developments in our understanding of the enzymology, chemistry, biochemistry and biologic roles of mammalian peroxidases and the oxidants that they generate, the potential role of these oxidants in human disease, and the use of the levels of these enzymes in disease prognosis.
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Affiliation(s)
- Michael J Davies
- The Heart Research Institute, Camperdown, University of Sydney, Sydney, Australia., Faculty of Medicine, University of Sydney, Sydney, Australia.
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Incerpi S, Fiore AM, De Vito P, Pedersen JZ. Involvement of plasma membrane redox systems in hormone action. J Pharm Pharmacol 2008; 59:1711-20. [PMID: 18053334 DOI: 10.1211/jpp.59.12.0014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Reactive oxygen species (ROS) is the common name used to describe the partially reduced forms of molecular oxygen that may be generated in cells during oxidative metabolism. They are normally considered to be toxic, and cells possess various defence systems to protect themselves including antioxidant enzymes and low molecular weight antioxidants like vitamin C and vitamin E. However, it is now clear that small amounts of ROS also act as messenger molecules in cell signal transduction pathways; the plasma membrane of eukaryotic cells in particular contains a variety of different ROS-producing oxidases and reductases, of which the best characterized are the superoxide-producing NADPH oxidases. It has been known for many years that membrane redox activity can be changed rapidly by various hormones and growth factors, but the molecular mechanisms involved and the physiological importance of this phenomenon have only recently begun to be unveiled. This review summarizes the state of the art on plasma membrane-based ROS signalling in the pathways of insulin, steroid and thyroid hormones and growth factors. The apparent paradox of ROS being essential biomolecules in the regulation of cellular functions, but also toxic by-products of metabolism, may be important for the pharmacological application of natural and synthetic antioxidants.
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Affiliation(s)
- Sandra Incerpi
- Department of Biology, University of Rome 'Roma Tre', Viale Marconi 446, 00146 Roma, Italy.
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Hogan SP, Rosenberg HF, Moqbel R, Phipps S, Foster PS, Lacy P, Kay AB, Rothenberg ME. Eosinophils: biological properties and role in health and disease. Clin Exp Allergy 2008; 38:709-50. [PMID: 18384431 DOI: 10.1111/j.1365-2222.2008.02958.x] [Citation(s) in RCA: 554] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Eosinophils are pleiotropic multifunctional leukocytes involved in initiation and propagation of diverse inflammatory responses, as well as modulators of innate and adaptive immunity. In this review, the biology of eosinophils is summarized, focusing on transcriptional regulation of eosinophil differentiation, characterization of the growing properties of eosinophil granule proteins, surface proteins and pleiotropic mediators, and molecular mechanisms of eosinophil degranulation. New views on the role of eosinophils in homeostatic function are examined, including developmental biology and innate and adaptive immunity (as well as their interaction with mast cells and T cells) and their proposed role in disease processes including infections, asthma, and gastrointestinal disorders. Finally, strategies for targeted therapeutic intervention in eosinophil-mediated mucosal diseases are conceptualized.
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Wang J, Mahmud SA, Bitterman PB, Huo Y, Slungaard A. Histone deacetylase inhibitors suppress TF-kappaB-dependent agonist-driven tissue factor expression in endothelial cells and monocytes. J Biol Chem 2007; 282:28408-28418. [PMID: 17675290 DOI: 10.1074/jbc.m703586200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Histone deacetylase inhibitors (HDACi), such as trichostatin A (TSA), can regulate gene expression by promoting acetylation of histones and transcription factors. Human tissue factor (TF) expression is partly governed by a unique, NF-kappaB-related "TF-kappaB" promoter binding site. We find that TSA and four other HDACi (apicidin, MS-275, sodium butyrate, and valproic acid) all inhibit by approximately 90% TF activity and protein level induction in human umbilical vein endothelial cells stimulated by the physiologic agonists tumor necrosis factor (TNF)-alpha, interleukin-1beta, lipopolysaccharide, and HOSCN without affecting expression of the NF-kappaB-regulated adhesion molecules ICAM-1 and E-selectin. TSA and butyrate also blunt TF induction approximately 50% in vitro in peripheral blood mononuclear cells and in vivo in thioglycolate-elicited murine peritoneal macrophages. In human umbilical vein endothelial cells, TSA attenuates by approximately 70% TNF-alpha stimulation of TF mRNA transcription without affecting that of ICAM-1. By electrophoretic mobility shift assay analyses, TNF-alpha and lipopolysaccharide induce strong p65/p50 and p65/c-Rel heterodimer binding to both NF-kappaB and TF-kappaB probes. TSA nearly abolishes TF-kappaB binding without affecting NF-kappaB binding. A chromatin immunoprecipitation assay and a promoter-luciferase reporter system confirm that TSA inhibits TF-kappaB but not NF-kappaB activation. Chromatin immunoprecipitation and small interfering RNA inhibitor studies demonstrate that HDAC3 plays a significant role in TNF-alpha-mediated TF induction. Thus, HDACi transcriptionally inhibit agonist-induced TF expression in endothelial cells and monocytes by a TF-kappaB- and HDAC3-dependent mechanism. We conclude that histone deacetylases, particularly HDAC3, play a hitherto unsuspected role in regulating TF expression and raise the possibility that HDACi might be a novel therapy for thrombotic disorders.
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Affiliation(s)
- Jianguo Wang
- Sections of Hematology, Oncology, and Transplantation, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Medicine Department, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Vascular Biology Center, University of Minnesota, Minneapolis, Minnesota 55455
| | - Shawn A Mahmud
- Sections of Hematology, Oncology, and Transplantation, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Medicine Department, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Vascular Biology Center, University of Minnesota, Minneapolis, Minnesota 55455
| | - Peter B Bitterman
- Sections of Medicine Department, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Pulmonary and Critical Care, University of Minnesota, Minneapolis, Minnesota 55455
| | - Yuqing Huo
- Sections of Medicine Department, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Vascular Biology Center, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Cardiology, University of Minnesota, Minneapolis, Minnesota 55455
| | - Arne Slungaard
- Sections of Hematology, Oncology, and Transplantation, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Medicine Department, University of Minnesota, Minneapolis, Minnesota 55455; Sections of Vascular Biology Center, University of Minnesota, Minneapolis, Minnesota 55455.
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Pedemonte N, Caci E, Sondo E, Caputo A, Rhoden K, Pfeffer U, Di Candia M, Bandettini R, Ravazzolo R, Zegarra-Moran O, Galietta LJV. Thiocyanate transport in resting and IL-4-stimulated human bronchial epithelial cells: role of pendrin and anion channels. THE JOURNAL OF IMMUNOLOGY 2007; 178:5144-53. [PMID: 17404297 DOI: 10.4049/jimmunol.178.8.5144] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
SCN(-) (thiocyanate) is an important physiological anion involved in innate defense of mucosal surfaces. SCN(-) is oxidized by H(2)O(2), a reaction catalyzed by lactoperoxidase, to produce OSCN(-) (hypothiocyanite), a molecule with antimicrobial activity. Given the importance of the availability of SCN(-) in the airway surface fluid, we studied transepithelial SCN(-) transport in the human bronchial epithelium. We found evidence for at least three mechanisms for basolateral to apical SCN(-) flux. cAMP and Ca(2+) regulatory pathways controlled SCN(-) transport through cystic fibrosis transmembrane conductance regulator and Ca(2+)-activated Cl(-) channels, respectively, the latter mechanism being significantly increased by treatment with IL-4. Stimulation with IL-4 also induced the strong up-regulation of an electroneutral SCN(-)/Cl(-) exchange. Global gene expression analysis with microarrays and functional studies indicated pendrin (SLC26A4) as the protein responsible for this SCN(-) transport. Measurements of H(2)O(2) production at the apical surface of bronchial cells indicated that the extent of SCN(-) transport is important to modulate the conversion of this oxidant molecule by the lactoperoxidase system. Our studies indicate that the human bronchial epithelium expresses various SCN(-) transport mechanisms under resting and stimulated conditions. Defects in SCN(-) transport in the airways may be responsible for susceptibility to infections and/or decreased ability to scavenge oxidants.
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40
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Yap YW, Whiteman M, Cheung NS. Chlorinative stress: an under appreciated mediator of neurodegeneration? Cell Signal 2006; 19:219-28. [PMID: 16959471 DOI: 10.1016/j.cellsig.2006.06.013] [Citation(s) in RCA: 372] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 06/29/2006] [Indexed: 01/23/2023]
Abstract
Oxidative stress has been implicated as playing a role in neurodegenerative disorders, such as ischemic stroke, Alzheimer's, Huntington's, and Parkinson's disease. Persuasive evidences have shown that microglial-mediated oxidative stress contributes significantly to cell loss and accompanying cognitive decline characteristic of the diseases. Based on the facts that (i) levels of catalytically active myeloperoxidase are elevated in diseased brains and (ii) myeloperoxidase polymorphism is associated with the risk of developing neurodegenerative disorders, HOCl as a major oxidant produced by activated phagocytes in the presence of myeloperoxidase is therefore suggested to be involved in neurodegeneration. Its association with neurodegeneration is further showed by elevated level of 3-chlorotyrosine (bio-marker of HOCl in vivo) in affected brain regions as well as HOCl scavenging ability of neuroprotectants, desferrioxamine and uric acid. In this review, we will summary the current understanding concerning the association of HOCl and neuronal cell death where production of HOCl will lead to further formation of reactive nitrogen and oxygen species. In addition, HOCl also causes tissue destruction and cellular damage leading cell death.
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Affiliation(s)
- Yann Wan Yap
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
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41
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Anichina J, Zhao X, Bohme DK. Metal- and Ligation-Dependent Fragmentation of [M(1,10-Phenanthroline)1,2,3]2+ Cations with M = Mn, Fe, Co, Ni, Cu, and Zn: Comparison between the Gas Phase and Solution. J Phys Chem A 2006; 110:10763-9. [PMID: 16970369 DOI: 10.1021/jp0624707] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The core ions [ML(n)]2+ with n = 1-3, where L = 1,10-phenanthroline and M is a first-row transition metal, have been successfully transferred from aqueous solution into the gas phase by electrospraying and then probed for their stabilities by collision-induced dissociation in a triple quadrupole mass spectrometer. The triply ligated metal dications [ML3]2+ were observed to dissociate by the extrusion of a neutral ligand, while ligand loss from both [ML2]2+ and [ML]2+ was accompanied by electron transfer. Comparisons are provided between gas-phase stabilities and stabilities for ligand loss measured in aqueous solution at 298 K. The measured onset for ligand loss from [ML3]2+ is quite insensitive to the metal, while a distinct stability order has been reported for aqueous solution. Low level density functional theory (DFT) calculations predict an intrinsic stability order for loss of ligand from [ML2]2+, but it differs from that in aqueous solution. Substantial agreement was obtained for the stability order for the loss of ligand from [ML]2+ deduced from onset energies measured for charge separation, computed with DFT, and reported for aqueous solution where hydration seems less decisive in influencing this stability order. A qualitative potential-energy diagram is presented that allows the energy for charge separation to be related to the energy for neutral ligand loss from [ML]2+ and shows that IE(M+) is decisive in determining the intrinsic stability order for loss of ligand from [ML]2+.
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Affiliation(s)
- Janna Anichina
- Department of Chemistry, Centre for Research in Mass Spectrometry, York University, Toronto, Ontario, Canada, M3J 1P3
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Ashby MT, Aneetha H, Carlson AC, Scott MJ, Beal JL. Bioorganic Chemistry of Hypothiocyanite. PHOSPHORUS SULFUR 2006. [DOI: 10.1080/10426500590912664] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Michael T. Ashby
- a Department of Chemistry and Biochemistry , University of Oklahoma , Norman, USA
| | - Halikhedkar Aneetha
- a Department of Chemistry and Biochemistry , University of Oklahoma , Norman, USA
| | - Amy C. Carlson
- a Department of Chemistry and Biochemistry , University of Oklahoma , Norman, USA
| | - M. Jared Scott
- a Department of Chemistry and Biochemistry , University of Oklahoma , Norman, USA
| | - Jennifer L. Beal
- a Department of Chemistry and Biochemistry , University of Oklahoma , Norman, USA
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van Dalen C, Winterbourn C, Kettle A. Mechanism of nitrite oxidation by eosinophil peroxidase: implications for oxidant production and nitration by eosinophils. Biochem J 2006; 394:707-13. [PMID: 16336215 PMCID: PMC1383721 DOI: 10.1042/bj20051470] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Eosinophil peroxidase is a haem enzyme of eosinophils that is implicated in oxidative tissue injury in asthma. It uses hydrogen peroxide to oxidize thiocyanate and bromide to their respective hypohalous acids. Nitrite is also a substrate for eosinophil peroxidase. We have investigated the mechanisms by which the enzyme oxidizes nitrite. Nitrite was very effective at inhibiting hypothiocyanous acid ('cyanosulphenic acid') and hypobromous acid production. Spectral studies showed that nitrite reduced the enzyme to its compound II form, which is a redox intermediate containing Fe(IV) in the haem active site. Compound II does not oxidize thiocyanate or bromide. These results demonstrate that nitrite is readily oxidized by compound I, which contains Fe(V) at the active site. However, it reacts more slowly with compound II. The observed rate constant for reduction of compound II by nitrite was determined to be 5.6x10(3) M(-1) x s(-1). Eosinophils were at least 4-fold more effective at promoting nitration of a heptapeptide than neutrophils. This result is explained by our finding that nitrite reacts 10-fold faster with compound II of eosinophil peroxidase than with the analogous redox intermediate of myeloperoxidase. Nitration by eosinophils was increased 3-fold by superoxide dismutase, which indicates that superoxide interferes with nitration. We propose that at sites of eosinophilic inflammation, low concentrations of nitrite will retard oxidant production by eosinophil peroxidase, whereas at higher concentrations nitrogen dioxide will be a major oxidant formed by these cells. The efficiency of protein nitration will be decreased by the diffusion-controlled reaction of superoxide with nitrogen dioxide.
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Affiliation(s)
| | - Christine C. Winterbourn
- †Free Radical Research, Department of Pathology, Christchurch School of Medicine and Health Sciences, Christchurch, New Zealand
| | - Anthony J. Kettle
- †Free Radical Research, Department of Pathology, Christchurch School of Medicine and Health Sciences, Christchurch, New Zealand
- To whom correspondence should be addressed (email )
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Ciaccio C, Gambacurta A, De Sanctis G, Spagnolo D, Sakarikou C, Petrella G, Coletta M. rhEPO (recombinant human eosinophil peroxidase): expression in Pichia pastoris and biochemical characterization. Biochem J 2006; 395:295-301. [PMID: 16396635 PMCID: PMC1422775 DOI: 10.1042/bj20051385] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2005] [Revised: 12/02/2005] [Accepted: 01/06/2006] [Indexed: 11/17/2022]
Abstract
A Pichia pastoris expression system has for the first time been successfully developed to produce rhEPO (recombinant human eosinophil peroxidase). The full-length rhEPO coding sequence was cloned into the pPIC9 vector in frame with the yeast alpha-Factor secretion signal under the transcriptional control of the AOX (acyl-CoA oxidase) promoter, and transformed into P. pastoris strain GS115. Evidence for the production of rhEPO by P. pastoris as a glycosylated dimer precursor of approx. 80 kDa was determined by SDS/PAGE and gel filtration chromatography. Recombinant hEPO undergoes proteolytic processing, similar to that in the native host, to generate two chains of approx. 50 and 20 kDa. A preliminary biochemical characterization of purified rhEPO demonstrated that the spectral and kinetic properties of the recombinant wild-type EPO are comparable with those of the native enzyme and are accompanied by oxidizing activity towards several physiological anionic substrates such as SCN-, Br- and Cl-. On the basis of the estimated K(m) and kcat values it is evident that the pseudohalide SCN- is the most specific substrate for rhEPO, consistent with the catalytic properties of other mammalian EPOs purified from blood.
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Affiliation(s)
- Chiara Ciaccio
- Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Via Montpellier 1, I-00133 Roma, Italy.
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45
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Wang J, Slungaard A. Role of eosinophil peroxidase in host defense and disease pathology. Arch Biochem Biophys 2005; 445:256-60. [PMID: 16297853 DOI: 10.1016/j.abb.2005.10.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2005] [Revised: 10/04/2005] [Accepted: 10/10/2005] [Indexed: 11/28/2022]
Abstract
Three unusual substrates-bromide (Br(-)), nitrite (NO(2)(-)), and thiocyanate (SCN(-))-compete for oxidation by eosinophil peroxidase (EPO) in physiologic fluids in the presence of H(2)O(2) to yield, respectively, hypobromous acid (HOBr), nitrogen dioxide (NO(2)()), or hypothiocyanous acid (HOSCN). These oxidant products have strikingly different reactivities: HOBr and NO(2)() are potent, widely reactive, membrane-lytic oxidants whereas HOSCN is a weak, SH-specific oxidant that penetrates into cells and imposes an intracellular oxidant stress that can activate kinase pathways and transcription factors that profoundly influence gene expression in host cells. All three oxidants are lethal for pathogens. SCN(-) is the strongly preferred substrate for the EPO/H(2)O(2). Specific biomarkers document that EPO-dependent oxidants are generated at sites of inflammation, but direct evidence that these oxidants cause disease is confined to the observation that an EPO knockout mouse line has dramatically less pathologic damage than do wild type animals in a murine model of ulcerative colitis.
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Affiliation(s)
- Jianguo Wang
- University of Minnesota, Department of Medicine, Section of Hematology, Oncology and Transplantation and The Vascular Biology Center, Minneapolis, MN, USA
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46
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Wojciechowski G, Huang L, Ortiz de Montellano PR. Autocatalytic Modification of the Prosthetic Heme of Horseradish but Not Lactoperoxidase by Thiocyanate Oxidation Products. A Role for Heme−Protein Covalent Cross-Linking. J Am Chem Soc 2005; 127:15871-9. [PMID: 16277530 DOI: 10.1021/ja054084t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mammalian peroxidases eosinophil peroxidase, lactoperoxidase (LPO), and myeloperoxidase oxidize thiocyanate to the antimicrobial agents hypothiocyanous acid (HOSCN) and (SCN)2 and are part of a defense system that protects the host from infections. Horseradish peroxidase (HRP), a plant enzyme, also oxidizes thiocyanate. We report here that the prosthetic heme vinyl groups of HRP react with the catalytically generated HOSCN and (SCN)2 to form at least nine vinyl-modified heme adducts. Mass spectrometry combined with analysis of the equivalent reactions of HRP reconstituted with 2- or 4-cyclopropylheme, or mesoheme-d4, shows that all of the prosthetic heme modifications result from addition of oxidized thiocyanate to the heme vinyl groups. No delta-meso-substitution of the heme was observed, in contrast to what is observed with radical agents. Model studies show that incubation of either HRP with preformed HOSCN or a solution of heme with preformed (SCN)2 gives rise to the same products obtained in the HRP-catalyzed reaction. Model studies also demonstrate that the SCN* radical, if formed, should add to a meso-carbon. These findings implicate an electrophilic addition mechanism. In contrast, oxidation by LPO of thiocyanate, the normal substrate of this enzyme, does not result in heme modification. In view of the demonstrated intrinsic reactivity of the heme group, LPO must actively suppress heme modification. As the key difference between LPO (and other mammalian peroxidases) and HRP is the presence of two covalent ester links between the heme and the protein, we propose that these links contribute to steric protection of the adjacent heme vinyl groups.
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Affiliation(s)
- Grzegorz Wojciechowski
- Department of Pharmaceutical Chemistry, University of California, 600 16th Street, San Francisco, California 94143-2280, USA
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Wang JG, Mahmud SA, Thompson JA, Geng JG, Key NS, Slungaard A. The principal eosinophil peroxidase product, HOSCN, is a uniquely potent phagocyte oxidant inducer of endothelial cell tissue factor activity: a potential mechanism for thrombosis in eosinophilic inflammatory states. Blood 2005; 107:558-65. [PMID: 16166591 PMCID: PMC1895611 DOI: 10.1182/blood-2005-05-2152] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In vivo, bromide (Br(-)), nitrite (NO(2)(-)), and thiocyanate (SCN(-)) compete for oxidation by eosinophil peroxidase (EPO) and H(2)O(2), yielding, respectively, HOBr, NO(2)., and HOSCN. We have recently shown that SCN(-) is the strongly preferred substrate for EPO in vivo and that HOSCN, in contrast with other EPO-generated oxidants and HOCl, is a relatively weak, cell-permeant, sulfhydryl (SH)-reactive oxidant. We here show that HOSCN is a uniquely potent (up to 100-fold) phagocyte oxidant inducer of tissue factor (TF) activity in human umbilical vein endothelial cells (HUVECs). This induction is attributable to transcriptional up-regulation of TF gene expression dependent upon both activation of the p65/c-Rel TF-kappaB transcription factor and activity of the ERK1/2 kinase pathway upstream of Egr-1 and was markedly further enhanced in the presence of wortmannin, an inhibitor of the PI3 kinase/Akt pathway. HOSCN also markedly activates the proinflammatory p65/p50 NF-kappaB pathway. Based on these findings we hypothesize that HOSCN generated by adherent and infiltrating eosinophils may provoke the development of a prothrombotic and proinflammatory endothelial/endocardial phenotype that promotes the pronounced thrombotic diathesis characteristic of the hypereosinophilic syndrome.
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Affiliation(s)
- Jian-Guo Wang
- Hematology, Oncology, and Transplantation Section, Department of Medicine, and the Vascular Biology Center, University of Minnesota, Minneapolis, USA
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Kettle AJ, Chan T, Osberg I, Senthilmohan R, Chapman ALP, Mocatta TJ, Wagener JS. Myeloperoxidase and Protein Oxidation in the Airways of Young Children with Cystic Fibrosis. Am J Respir Crit Care Med 2004; 170:1317-23. [PMID: 15466253 DOI: 10.1164/rccm.200311-1516oc] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Cystic fibrosis (CF) is characterized by considerable oxidative stress. However, it is not known whether oxidative stress is an important feature early in this disease. We have investigated a group of infants and young children with CF to establish whether oxidants are produced in their airways. Bronchoalveolar lavage fluid (BALF) was assayed for myeloperoxidase as a measure of neutrophilic inflammation, and 3-chlorotyrosine as a biomarker of the potent oxidant hypochlorous acid, which is formed by myeloperoxidase. Protein carbonyls were also measured as a nonspecific indicator of reactive oxidant production. Myeloperoxidase and 3-chlorotyrosine levels in BALF from children with CF were 10- and fivefold higher, respectively, than in disease control subjects. There was a strong correlation between myeloperoxidase and 3-chlorotyrosine. Myeloperoxidase levels were fourfold higher in children with infections in their airways. Median protein carbonyls were elevated by only twofold compared with disease control subjects, but some children had extremely high levels of protein oxidation. We conclude that hypochlorous acid is produced early in CF and that it is a candidate for precipitating the fatal decline in lung function associated with this disease. Also, there must be other sourcesof oxidants because protein carbonyls were not related to either inflammation or infection.
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Affiliation(s)
- Anthony J Kettle
- Free Radical Research Group, Department of Pathology, Christchurch School of Medicine and Health Sciences, P.O. Box 4345, Christchurch, New Zealand.
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Ashby MT, Aneetha H. Reactive sulfur species: aqueous chemistry of sulfenyl thiocyanates. J Am Chem Soc 2004; 126:10216-7. [PMID: 15315413 DOI: 10.1021/ja048585a] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sulfenyl thiocyanate (RSSCN) derivatives of penicillamine (PENSCN) and glutathione (GSSCN) have been synthesized in situ at pH = 0 from equilibrium mixtures that consists of hypothiocyanous acid (HOSCN), thiocyanogen ((SCN)2), and trithiocyanate ((SCN)3-). The electrophilic thiocyanating agent N-thiocyanatosuccinimide (NTS) also reacts with PEN and GSH to yield the corresponding RSSCN derivatives. PENSCN and GSSCN were characterized by NMR, ES-MS, and IR spectroscopy. While stable at pH = 0, at higher pH the RSSCN derivatives decompose to give products that are consistent with hydrolysis and formation of reactive sulfenic acids.
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Affiliation(s)
- Michael T Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Norman, OK 73019, USA
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