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Sadowska-Bartosz I, Bartosz G. The Cellular and Organismal Effects of Nitroxides and Nitroxide-Containing Nanoparticles. Int J Mol Sci 2024; 25:1446. [PMID: 38338725 PMCID: PMC10855878 DOI: 10.3390/ijms25031446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/21/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
Nitroxides are stable free radicals that have antioxidant properties. They react with many types of radicals, including alkyl and peroxyl radicals. They act as mimics of superoxide dismutase and stimulate the catalase activity of hemoproteins. In some situations, they may exhibit pro-oxidant activity, mainly due to the formation of oxoammonium cations as products of their oxidation. In this review, the cellular effects of nitroxides and their effects in animal experiments and clinical trials are discussed, including the beneficial effects in various pathological situations involving oxidative stress, protective effects against UV and ionizing radiation, and prolongation of the life span of cancer-prone mice. Nitroxides were used as active components of various types of nanoparticles. The application of these nanoparticles in cellular and animal experiments is also discussed.
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Affiliation(s)
- Izabela Sadowska-Bartosz
- Laboratory of Analytical Biochemistry, Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszow, 4 Zelwerowicza Street, 35-601 Rzeszow, Poland;
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Mujagić A, Marushima A, Nagasaki Y, Hosoo H, Hirayama A, Puentes S, Takahashi T, Tsurushima H, Suzuki K, Matsui H, Ishikawa E, Matsumaru Y, Matsumura A. Antioxidant nanomedicine with cytoplasmic distribution in neuronal cells shows superior neurovascular protection properties. Brain Res 2020; 1743:146922. [PMID: 32504549 DOI: 10.1016/j.brainres.2020.146922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/20/2020] [Accepted: 06/01/2020] [Indexed: 01/15/2023]
Abstract
This study investigated whether nitroxide radical (4-amino-TEMPOL)-containing nanoparticles (RNPs; antioxidant nanomedicine) can prevent neurovascular unit impairment caused by reactive oxygen species (ROS) after cerebral ischemia-reperfusion. C57BL/6J mice underwent transient middle cerebral artery occlusion (tMCAO). The mice were randomly divided and administered intra-arterial RNPs injection (9 mg/kg, 7 μM/kg), edaravone (3 mg/kg, 17 μM/kg), or phosphate-buffered saline (control group). Survival rate and neurological score were evaluated 24 h post-injection. RNPs distribution was determined using immunofluorescence staining and blood-brain barrier (BBB) disruption using Evans blue extravasation assay. Effect of RNPs and edaravone on microglia polarization into microglia M1 and M2 was evaluated. We also determined multiple ROS-scavenging activities in brain homogenates of RNPs- and edaravone-treated animals using an electron spin resonance-based spin-trapping method. Compared with edaravone, RNPs significantly improved the survival rate and neurological deficit, inhibited BBB disruption and supported polarization of microglia into M2 microglia. RNPs were localized in endothelial cells, the perivascular space, neuronal cell cytoplasm, astrocytes, and microglia. Scavenging capacities of hydroxyl, alkoxyl, and peroxyl radicals were significantly higher in the RNPs-treated group. RNPs show promising results as a future neuroprotective nanomedicine approach for cerebral ischemia-reperfusion injury.
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Affiliation(s)
- Arnela Mujagić
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Aiki Marushima
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan.
| | - Yukio Nagasaki
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Hisayuki Hosoo
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Aki Hirayama
- Center for Integrative Medicine, Tsukuba University of Technology, Kasuga 4-12-7, Tsukuba, Ibaraki, Japan
| | - Sandra Puentes
- Graduate School of Systems and Information Engineering, University of Tsukuba, Tennodai 1-1-1, Ibaraki, Japan
| | - Toshihide Takahashi
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Hideo Tsurushima
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Kensuke Suzuki
- Department of Neurosurgery, Saitama Medical Center, Dokkyo Medical University, Minami-Koshigaya 2-1-50, Koshigaya, Saitama, Japan
| | - Hirofumi Matsui
- Department of Gastroenterology, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Eiichi Ishikawa
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Yuji Matsumaru
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
| | - Akira Matsumura
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
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Verderosa AD, Dhouib R, Fairfull-Smith KE, Totsika M. Nitroxide Functionalized Antibiotics Are Promising Eradication Agents against Staphylococcus aureus Biofilms. Antimicrob Agents Chemother 2019; 64:e01685-19. [PMID: 31636066 PMCID: PMC7187575 DOI: 10.1128/aac.01685-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 10/09/2019] [Indexed: 01/10/2023] Open
Abstract
Treatment of biofilm-related Staphylococcus aureus infections represents an important medical challenge worldwide, as biofilms, even those involving drug-susceptible S. aureus strains, are highly refractory to conventional antibiotic therapy. Nitroxides were recently shown to induce the dispersal of Gram-negative biofilms in vitro, but their action against Gram-positive bacterial biofilms remains unknown. Here, we demonstrate that the biofilm dispersal activity of nitroxides extends to S. aureus, a clinically important Gram-positive pathogen. Coadministration of the nitroxide CTEMPO (4-carboxy-2,2,6,6-tetramethylpiperidin-1-yloxyl) with ciprofloxacin significantly improved the biofilm eradication activity of the antibiotic against S. aureus Moreover, covalently linking the nitroxide to the antibiotic moiety further reduced the ciprofloxacin minimal biofilm eradication concentration. Microscopy analysis revealed that fluorescent nitroxide-antibiotic hybrids could penetrate S. aureus biofilms and enter cells localized at the surface and base of the biofilm structure. No toxicity to human cells was observed for the nitroxide CTEMPO or the nitroxide-antibiotic hybrids. Taken together, our results show that nitroxides can mediate the dispersal of Gram-positive biofilms and that dual-acting biofilm eradication antibiotics may provide broad-spectrum therapies for the treatment of biofilm-related infections.
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Affiliation(s)
- Anthony D Verderosa
- School of Chemistry, Physics, and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland, Australia
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Rabeb Dhouib
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Kathryn E Fairfull-Smith
- School of Chemistry, Physics, and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Makrina Totsika
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
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Molecular Probes for Evaluation of Oxidative Stress by In Vivo EPR Spectroscopy and Imaging: State-of-the-Art and Limitations. MAGNETOCHEMISTRY 2019. [DOI: 10.3390/magnetochemistry5010013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oxidative stress, defined as a misbalance between the production of reactive oxygen species and the antioxidant defenses of the cell, appears as a critical factor either in the onset or in the etiology of many pathological conditions. Several methods of detection exist. However, they usually rely on ex vivo evaluation or reports on the status of living tissues only up to a few millimeters in depth, while a whole-body, real-time, non-invasive monitoring technique is required for early diagnosis or as an aid to therapy (to monitor the action of a drug). Methods based on electron paramagnetic resonance (EPR), in association with molecular probes based on aminoxyl radicals (nitroxides) or hydroxylamines especially, have emerged as very promising to meet these standards. The principles involve monitoring the rate of decrease or increase of the EPR signal in vivo after injection of the nitroxide or the hydroxylamine probe, respectively, in a pathological versus a control situation. There have been many successful applications in various rodent models. However, current limitations lie in both the field of the technical development of the spectrometers and the molecular probes. The scope of this review will mainly focus on the latter.
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Spejo AB, Teles CB, Zuccoli GDS, Oliveira ALRD. Synapse preservation and decreased glial reactions following ventral root crush (VRC) and treatment with 4‐hydroxy‐tempo (TEMPOL). J Neurosci Res 2018; 97:520-534. [DOI: 10.1002/jnr.24365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/20/2018] [Accepted: 11/20/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Aline Barroso Spejo
- Department of Structural and Functional Biology, Institute of Biology University of Campinas (UNICAMP) Campinas Brazil
| | - Caroline Brandão Teles
- Department of Structural and Functional Biology, Institute of Biology University of Campinas (UNICAMP) Campinas Brazil
| | - Giuliana da Silva Zuccoli
- Department of Structural and Functional Biology, Institute of Biology University of Campinas (UNICAMP) Campinas Brazil
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Geng S, Wei J, Aitomäki Y, Noël M, Oksman K. Well-dispersed cellulose nanocrystals in hydrophobic polymers by in situ polymerization for synthesizing highly reinforced bio-nanocomposites. NANOSCALE 2018; 10:11797-11807. [PMID: 29675528 DOI: 10.1039/c7nr09080c] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In nanocomposites, dispersing hydrophilic nanomaterials in a hydrophobic matrix using simple and environmentally friendly methods remains challenging. Herein, we report a method based on in situ polymerization to synthesize nanocomposites of well-dispersed cellulose nanocrystals (CNCs) and poly(vinyl acetate) (PVAc). We have also shown that by blending this PVAc/CNC nanocomposite with poly(lactic acid) (PLA), a good dispersion of the CNCs can be reached in PLA. The outstanding dispersion of CNCs in both PVAc and PLA/PVAc matrices was shown by different microscopy techniques and was further supported by the mechanical and rheological properties of the composites. The in situ PVAc/CNC nanocomposites exhibit enhanced mechanical properties compared to the materials produced by mechanical mixing, and a theoretical model based on the interphase effect and dispersion that reflects this behavior was developed. Comparison of the rheological and thermal behaviors of the mixed and in situ PVAc/CNC also confirmed the great improvement in the dispersion of nanocellulose in the latter. Furthermore, a synergistic effect was observed with only 0.1 wt% CNCs when the in situ PVAc/CNC was blended with PLA, as demonstrated by significant increases in elastic modulus, yield strength, elongation to break and glass transition temperature compared to the PLA/PVAc only material.
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Affiliation(s)
- Shiyu Geng
- Division of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, SE-971 87, Luleå, Sweden.
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Hosoo H, Marushima A, Nagasaki Y, Hirayama A, Ito H, Puentes S, Mujagic A, Tsurushima H, Tsuruta W, Suzuki K, Matsui H, Matsumaru Y, Yamamoto T, Matsumura A. Neurovascular Unit Protection From Cerebral Ischemia-Reperfusion Injury by Radical-Containing Nanoparticles in Mice. Stroke 2017; 48:2238-2247. [PMID: 28655813 DOI: 10.1161/strokeaha.116.016356] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 05/24/2017] [Accepted: 05/26/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND PURPOSE Reperfusion therapy by mechanical thrombectomy is used to treat acute ischemic stroke. However, reactive oxygen species generation after reperfusion therapy causes cerebral ischemia-reperfusion injury, which aggravates cerebral infarction. There is limited evidence for clinical efficacy in stroke for antioxidants. Here, we developed a novel core-shell type nanoparticle containing 4-amino-4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (nitroxide radical-containing nanoparticles [RNPs]) and investigated its ability to scavenge reactive oxygen species and confer neuroprotection. METHODS C57BL/6J mice underwent transient middle cerebral artery occlusion and then received RNPs (9 mg/kg) through the common carotid artery. Infarction size, neurological scale, and blood-brain barrier damage were visualized by Evans blue extravasation 24 hours after reperfusion. RNP distribution was detected by rhodamine labeling. Blood-brain barrier damage, neuronal apoptosis, and oxidative neuronal cell damage were evaluated in ischemic brains. Multiple free radical-scavenging capacities were analyzed by an electron paramagnetic resonance-based method. RESULTS RNPs were detected in endothelial cells and around neuronal cells in the ischemic lesion. Infarction size, neurological scale, and Evans blue extravasation were significantly lower after RNP treatment. RNP treatment preserved the endothelium and endothelial tight junctions in the ischemic brain; neuronal apoptosis, O2- production, and gene oxidation were significantly suppressed. Reactive oxygen species scavenging capacities against OH, ROO, and O2- improved by RNP treatment. CONCLUSIONS An intra-arterial RNP injection after cerebral ischemia-reperfusion injury reduced blood-brain barrier damage and infarction volume by improving multiple reactive oxygen species scavenging capacities. Therefore, RNPs can provide neurovascular unit protection.
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Affiliation(s)
- Hisayuki Hosoo
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Aiki Marushima
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.).
| | - Yukio Nagasaki
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Aki Hirayama
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Hiromu Ito
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Sandra Puentes
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Arnela Mujagic
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Hideo Tsurushima
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Wataro Tsuruta
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Kensuke Suzuki
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Hirofumi Matsui
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Yuji Matsumaru
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Tetsuya Yamamoto
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
| | - Akira Matsumura
- From the Department of Neurosurgery, Faculty of Medicine (H.H., A.M., H.T., W.T., Y.M., T.Y., A.M.), Department of Neurosurgery, Graduate School of Comprehensive Human Science (H.H., A. Marushima, A. Mujagic, H.T., W.T., Y.M., T.Y., A.M.), Graduate School of Pure and Applied Sciences (Y.N.), Department of Gastroenterology, Graduate School of Comprehensive Human Science (H.I., H.M.), and Graduate School of Systems and Information Engineering (S.P.), University of Tsukuba, Ibaraki, Japan; Center for Integrative Medicine, Tsukuba University of Technology, Ibaraki, Japan (A.H.); and Department of Neurosurgery, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan (K.S.)
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Hu L, Wang Y, Cotrim AP, Zhu Z, Gao R, Zheng C, Goldsmith CM, Jin L, Zhang C, Mitchell JB, Baum BJ, Wang S. Effect of Tempol on the prevention of irradiation-induced mucositis in miniature pigs. Oral Dis 2017; 23:801-808. [PMID: 28326646 DOI: 10.1111/odi.12667] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/09/2017] [Accepted: 03/15/2017] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The goals of this study were to (i) establish a useful miniature pig (minipig) model for irradiation-induced oral mucositis and (ii) evaluate the effect of Tempol to prevent its development. METHODS AND MATERIALS Minipigs were irradiated with 6 Gy for five consecutive days targeting the entire oral cavity. To prevent radiation damage, minipigs were treated with 30 mg kg-1 Tempol 10 min before irradiation (n = 4), while the radiation-alone group was similarly injected with saline (n = 4). Lesions were graded using an oral mucositis score and visual inspection every 3 days, and biopsy of multiple sites was performed at day 18. Weight and chest and abdominal circumferences were measured every 3 days. RESULTS Lesions began about 12 days after the first irradiation fraction and healed about 30 days after irradiation. Epithelial thickness was calculated on the lingual and buccal mucosa on the 18th day after the first irradiation fraction. Tempol provided modest protection from ulceration after irradiation using this treatment strategy. CONCLUSIONS This study established a useful large animal model for irradiation-induced oral mucositis and showed modest beneficial effects of Tempol in limiting tissue damage. The latter finding may be potentially valuable in preventing oral mucositis in patients receiving irradiation for head and neck cancers.
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Affiliation(s)
- L Hu
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - Y Wang
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - A P Cotrim
- Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, NIH, DHHS, Bethesda, MD, USA
| | - Z Zhu
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - R Gao
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - C Zheng
- Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, NIH, DHHS, Bethesda, MD, USA
| | - C M Goldsmith
- Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, NIH, DHHS, Bethesda, MD, USA
| | - L Jin
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - C Zhang
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - J B Mitchell
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - B J Baum
- Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, NIH, DHHS, Bethesda, MD, USA
| | - S Wang
- Salivary Gland Disease Center and Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China.,Department of Biochemistry and Molecular Biology, Capital Medical University School of Basic Medical Sciences, Beijing, China
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9
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Vong LB, Kobayashi M, Nagasaki Y. Evaluation of the Toxicity and Antioxidant Activity of Redox Nanoparticles in Zebrafish (Danio rerio) Embryos. Mol Pharm 2016; 13:3091-7. [DOI: 10.1021/acs.molpharmaceut.6b00225] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Long Binh Vong
- Department
of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8573, Japan
| | - Makoto Kobayashi
- Department
of Molecular and Developmental Biology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8575, Japan
| | - Yukio Nagasaki
- Department
of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8573, Japan
- Master’s
School of Medical Sciences, Graduate School of Comprehensive Human
Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
- Satellite
Laboratory, International Center for Materials Nanoarchitectonics
(WPI-MANA), National Institute for Materials Science (NIMS), University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8573, Japan
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10
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Sadowska-Bartosz I, Galiniak S, Skolimowski J, Stefaniuk I, Bartosz G. Nitroxides prevent protein glycoxidationin vitro. Free Radic Res 2014; 49:113-21. [DOI: 10.3109/10715762.2014.982113] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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11
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Yoshitomi T, Nagasaki Y. Reactive oxygen species-scavenging nanomedicines for the treatment of oxidative stress injuries. Adv Healthc Mater 2014; 3:1149-61. [PMID: 24482427 DOI: 10.1002/adhm.201300576] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 01/06/2014] [Indexed: 12/14/2022]
Abstract
This Progress Report describes a development of two types of reactive oxygen species (ROS)-scavenging nanomedicines for the treatment of oxidative stress injuries, referred to as pH-sensitive redox nanoparticle (RNP(N) ) and pH-insensitive redox nanoparticle (RNP(O) ), which are prepared by self-assembling amphiphilic block copolymers possessing nitroxide radicals as a side chain of hydrophobic segment via amine and ether linkages, respectively. Due to a protonation of amino groups in hydrophobic core, RNP(N) disintegrates in low pH environments such as ischemic, inflamed, and tumor tissues, resulting in increased ROS-scavenging activity because of the exposed nitroxide radicals from the core. Utilizing pH-responsiveness of RNP(N) , it shows remarkable therapeutic effects on oxidative stress injuries such as renal and cerebral ischemia-reperfusion injuries after intravenous administration. Moreover, RNP(N) shows an enhancement of the activity of anticancer drugs by suppression of activation of transcription factors in tumor due to the ROS scavenging. On the other hand, orally administered RNP(O) has notable characteristics such as preferential accumulation in mucosa and inflamed area of gastrointestinal tract and no uptake into blood stream. Based on these characters, RNP(O) shows a remarkable therapeutic effect for the gastrointestinal inflammation without any adverse effects. Thus, ROS-scavenging nanomedicines have therapeutic efficacy in numerous oxidative stress diseases.
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Affiliation(s)
- Toru Yoshitomi
- Department of Chemistry, Graduate School of Science; The University of Tokyo; Bunkyo-ku 7-3-1 Tokyo 113-0033 Japan
| | - Yukio Nagasaki
- Department of Materials Sciences, Graduate School of Pure and Applied Sciences; University of Tsukuba; Tennoudai 1-1-1 Tsukuba Ibaraki 305-8573 Japan
- Master's School of Medical Sciences, Graduate School of Comprehensive Human Sciences; University of Tsukuba; Tennoudai 1-1-1 Tsukuba Ibaraki 305-8573 Japan
- Satellite Laboratory, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS); University of Tsukuba; Tennoudai 1-1-1 Tsukuba Ibaraki 305-8573 Japan
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12
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Kristensen MN, Frederiksen CA, Sivén E, Hyldebrandt JA, Juhl-Olsen P, Sloth E, Simonsen U, Buus NH. Negative inotropic and hypotensive effects of the superoxide dismutase mimetic tempol in pigs. Eur J Pharmacol 2014; 731:20-30. [PMID: 24632458 DOI: 10.1016/j.ejphar.2014.02.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 02/19/2014] [Accepted: 02/28/2014] [Indexed: 12/24/2022]
Abstract
Through interference with free radicals, the nitroxide tempol potentially increases bioavailability of nitric oxide (NO) and along with modulation of potassium channels reduces blood pressure (BP). We studied whether tempol in pigs lowers BP by mechanisms sensitive to inhibition of NO synthase or large conductance calcium-activated potassium channels (BKCa). The cardiovascular effects of intravenous tempol (25-50mg/kg) were examined in anesthetized pigs with myocardial function being evaluated by echocardiography. While saline-treated animals remained hemodynamically stable, tempol induced fast, dose-dependent and transient reductions in BP lasting 5-10 min with a simultaneous impairment of left ventricular contraction. Pretreatment with the NO synthase (NOS) inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME, 4 mg/kg) or a blocker of BKCa (tetraethylammonium (TEA), 100mg/h) increased baseline BP but also enhanced BP reductions to tempol. Isolated myocardial trabeculae subjected to an identical protocol also demonstrated dose-related reductions in contractility to tempol. This effect was not affected by l-NAME, but attenuated by TEA. In isolated mesenteric resistance arteries contracted with noradrenaline, tempol caused small postjunctional l-NAME sensitive relaxations, while neurogenic contractions were inhibited by tempol by TEA-sensitive mechanisms and mechanisms insensitive to TEA and l-NAME. In conclusion intravenous tempol induces fast transient reductions in BP associated with simultaneous reductions in myocardial contraction. Tempol exerts direct negative inotropic effects which are partly sensitive to BKCa-blockade but independent of NOS inhibition. In addition tempol has direct vasodilatory effects despite NOS and potassium channel blockade. The negative inotropic and hypotensive effects raise concerns using tempol, or structurally similar drugs, for intravenous use.
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Affiliation(s)
- Mads Nyboe Kristensen
- Institute of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Denmark
| | | | - Eleonora Sivén
- Institute of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Denmark; Department of Anesthesiology & Intensive Care, Aarhus University Hospital, Aarhus, Denmark
| | | | - Peter Juhl-Olsen
- Department of Anesthesiology & Intensive Care, Aarhus University Hospital, Aarhus, Denmark
| | - Erik Sloth
- Department of Anesthesiology & Intensive Care, Aarhus University Hospital, Aarhus, Denmark
| | - Ulf Simonsen
- Institute of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Denmark
| | - Niels Henrik Buus
- Institute of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Denmark.
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13
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Investigating retinal toxicity of tempol in a model of isolated and perfused bovine retina. Graefes Arch Clin Exp Ophthalmol 2014; 252:935-41. [PMID: 24789463 DOI: 10.1007/s00417-014-2632-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 03/12/2014] [Accepted: 03/31/2014] [Indexed: 02/03/2023] Open
Abstract
PURPOSE Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxyl) is a membrane-permeable superoxide dismutase and potentially neuroprotective substance. This study evaluates the retinal tolerance of 0.5 mM, 1 mM, 2 mM, and 5 mM tempol measured by the electroretinogram (ERG) of an isolated and perfused retina whole mount. METHODS For functionality testing, bovine retinas were prepared and perfused with an oxygen-saturated standard solution, and the ERG was recorded until stable b-wave amplitudes were reached. Tempol concentrations of 0.5 mM, 1 mM, 2 mM, and 5 mM were tested for 45 minutes. To investigate the effects on photoreceptor function, 1 mM aspartate was added to suppress the b-wave and obtain isolated a-waves. ERG amplitudes were monitored for 100 minutes. RESULTS While no toxic effects for concentrations of 0.5 mM and 1 mM tempol could be detected, concentrations of 2 mM tempol and higher caused statistically significant negative effects on the b-wave amplitude (-38 %, p = 0.02 for 2 mM; -54 %, p = 0.02 for 5 mM). The a-wave amplitude remained stable even at higher concentrations. CONCLUSIONS Although the photoreceptors seem to have a tolerance to high concentrations of tempol, higher intravitreal concentrations than 1 mM should be considered critical.
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14
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Guellich A, Damy T, Conti M, Claes V, Samuel JL, Pineau T, Lecarpentier Y, Coirault C. Tempol prevents cardiac oxidative damage and left ventricular dysfunction in the PPAR-α KO mouse. Am J Physiol Heart Circ Physiol 2013; 304:H1505-12. [PMID: 23542920 DOI: 10.1152/ajpheart.00669.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peroxisome proliferator-activated receptor (PPAR)-α deletion induces a profound decrease in MnSOD activity, leading to oxidative stress and left ventricular (LV) dysfunction. We tested the hypothesis that treatment of PPAR-α knockout (KO) mice with the SOD mimetic tempol prevents the heart from pathological remodelling and preserves LV function. Twenty PPAR-α KO mice and 20 age-matched wild-type mice were randomly treated for 8 wk with vehicle or tempol in the drinking water. LV contractile parameters were determined both in vivo using echocardiography and ex vivo using papillary muscle mechanics. Translational and posttranslational modifications of myosin heavy chain protein as well as the expression and activity of major antioxidant enzymes were measured. Tempol treatment did not affect LV function in wild-type mice; however, in PPAR-α KO mice, tempol prevented the decrease in LV ejection fraction and restored the contractile parameters of papillary muscle, including maximum shortening velocity, maximum extent of shortening, and total tension. Moreover, compared with untreated PPAR-α KO mice, myosin heavy chain tyrosine nitration and anion superoxide production were markedly reduced in PPAR-α KO mice after treatment. Tempol also significantly increased glutathione peroxidase and glutathione reductase activities (~ 50%) in PPAR-α KO mice. In conclusion, these findings demonstrate that treatment with the SOD mimetic tempol can prevent cardiac dysfunction in PPAR-α KO mice by reducing the oxidation of contractile proteins. In addition, we show that the beneficial effects of tempol in PPAR-α KO mice involve activation of the glutathione peroxidase/glutathione reductase system.
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Affiliation(s)
- Aziz Guellich
- Unité (U)69, Institut National de la Santé et de la Recherche Médicale (INSERM), Labex-Laboratoire d'Excellence en Recherche sur le Médicament et l'Innovation Thérapeutique, Université Paris Sud, Paris, France
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15
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Linares E, Seixas LV, dos Prazeres JN, Ladd FVL, Ladd AABL, Coppi AA, Augusto O. Tempol moderately extends survival in a hSOD1(G93A) ALS rat model by inhibiting neuronal cell loss, oxidative damage and levels of non-native hSOD1(G93A) forms. PLoS One 2013; 8:e55868. [PMID: 23405225 PMCID: PMC3566093 DOI: 10.1371/journal.pone.0055868] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 01/03/2013] [Indexed: 01/01/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive dysfunction and death of motor neurons by mechanisms that remain unclear. Evidence indicates that oxidative mechanisms contribute to ALS pathology, but classical antioxidants have not performed well in clinical trials. Cyclic nitroxides are an alternative worth exploring because they are multifunctional antioxidants that display low toxicity in vivo. Here, we examine the effects of the cyclic nitroxide tempol (4-hydroxy-2,2,6,6-tetramethyl piperidine-1-oxyl) on ALS onset and progression in transgenic female rats over-expressing the mutant hSOD1(G93A) . Starting at 7 weeks of age, a high dose of tempol (155 mg/day/rat) in the rat´s drinking water had marginal effects on the disease onset but decelerated disease progression and extended survival by 9 days. In addition, tempol protected spinal cord tissues as monitored by the number of neuronal cells, and the reducing capability and levels of carbonylated proteins and non-native hSOD1 forms in spinal cord homogenates. Intraperitoneal tempol (26 mg/rat, 3 times/week) extended survival by 17 days. This group of rats, however, diverted to a decelerated disease progression. Therefore, it was inconclusive whether the higher protective effect of the lower i.p. dose was due to higher tempol bioavailability, decelerated disease development or both. Collectively, the results show that tempol moderately extends the survival of ALS rats while protecting their cellular and molecular structures against damage. Thus, the results provide proof that cyclic nitroxides are alternatives worth to be further tested in animal models of ALS.
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Affiliation(s)
- Edlaine Linares
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Luciana V. Seixas
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Janaina N. dos Prazeres
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Fernando V. L. Ladd
- Laboratory of Stochastic Stereology and Chemical Anatomy, Department of Surgery, College of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Aliny A. B. L. Ladd
- Laboratory of Stochastic Stereology and Chemical Anatomy, Department of Surgery, College of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Antonio A. Coppi
- Laboratory of Stochastic Stereology and Chemical Anatomy, Department of Surgery, College of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Ohara Augusto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
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16
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Quan HH, Kang KS, Sohn YK, Li M. Tempol reduces injury area in rat model of spinal cord contusion injury through suppression of iNOS and COX-2 expression. Neurol Sci 2013; 34:1621-8. [DOI: 10.1007/s10072-013-1295-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 01/05/2013] [Indexed: 01/08/2023]
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17
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Thaler S, Voykov B, Willmann G, Fiedorowicz M, Rejdak R, Gekeler F, May CA, Schatz A, Schuettauf F. Tempol protects against intravitreous indocyanine green-induced retinal damage in rats. Graefes Arch Clin Exp Ophthalmol 2012; 250:1597-606. [PMID: 22460632 DOI: 10.1007/s00417-012-2000-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 02/23/2012] [Accepted: 03/09/2012] [Indexed: 11/29/2022] Open
Abstract
PURPOSE Indocyanine green (ICG) has been widely used as a vital dye for macular surgery. However, ICG can be toxic to retinal cells. Here we evaluate whether tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl), a free radical scavenger, can protect against ICG-induced retinal damage in rats. METHODS Brown Norway rats received intravitreal injections of ICG 0.5 % or BSS as controls. Tempol (20 mg/kg BW) or PBS as a control was administered intraperitoneally 24 h and 30 min before ICG and once daily for 7 consecutive days. Tempol was detected in the retina using electron paramagnetic resonance (EPR) spectroscopy. One week after ICG injections, the effects of tempol on retinal toxicity were assessed by retinal ganglion cell (RGC) back-labeling and by light microscopy. Electroretinography (ERG) was performed after 1 and 2 weeks. RESULTS ICG administration reduced RGC numbers by 17 % (1,943 ± 45 vs. 2,342 ± 31 RGCs/mm(2)). Tempol treatment rescued RGCs in a significant manner (2,258 ± 36, p < 0.01) and diminished morphological changes detected by light microscopy. ICG-injected eyes showed a significant reduction of ERG potentials only in PBS-treated animals (V(max) 530 ± 145 µV vs. 779 ± 179 µV, p = 0.0052), but not in the tempol-treated group. CONCLUSIONS Tempol significantly attenuates ICG-induced toxicity in rat retinas and may therefore be considered for further evaluation as accompanying treatment in ICG-assisted chromovitrectomy.
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Affiliation(s)
- Sebastian Thaler
- Centre for Ophthalmology, University of Tübingen, Röntgenweg 11, 72076, Tübingen, Germany.
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18
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Nitroxide radicals and nanoparticles: a partnership for nanomedicine radical delivery. Ther Deliv 2012; 3:165-79. [DOI: 10.4155/tde.11.153] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
This article aims to provide a research update on nitroxide radical compounds for application of anti-oxidative stress therapy. Nitroxide compounds such as 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO) can catalytically react with reactive oxygen species (ROS) and are anticipated as new anti-oxidant therapies for several diseases. However, low-molecular-weight nitroxide compounds pose several problems such as nonspecific dispersion in normal tissues, preferential renal clearance and rapid reduction of the nitroxide radical to the corresponding hydroxylamine. Nitroxide radical compounds are also known to show dose-related antihypertensive action accompanied by reflex tachycardia, increased skin temperature, and seizures. The author has recently designed novel nanoparticles, which possess nitroxide radicals in the core for novel bioimaging and nanotherapy. Nitroxide radical-containing nanoparticles (RNP) shows high safety, long blood circulation, magnetic resonance imaging and ESR imaging sensitive character and efficient therapeutic effects to several diseases such as cerebral and renal ischemia reperfusions, ulcerative colitis and Alzheimer’s disease models. RNPs are, thus, promising as new nanotherapeutic materials.
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Kappers MH, de Beer VJ, Zhou Z, Danser AJ, Sleijfer S, Duncker DJ, van den Meiracker AH, Merkus D. Sunitinib-Induced Systemic Vasoconstriction in Swine Is Endothelin Mediated and Does Not Involve Nitric Oxide or Oxidative Stress. Hypertension 2012; 59:151-7. [DOI: 10.1161/hypertensionaha.111.182220] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Angiogenesis inhibition with agents targeting tyrosine kinases of vascular endothelial growth factor receptors is an established anticancer treatment, but is, unfortunately, frequently accompanied by systemic hypertension and cardiac toxicity. Whether vascular endothelial growth factor receptor antagonism also has adverse effects on the pulmonary and coronary circulations is presently unknown. In chronically instrumented awake swine, the effects of the vascular endothelial growth factor receptor antagonist sunitinib on the systemic, pulmonary, and coronary circulation were studied. One week after sunitinib (50 mg PO daily), mean aortic blood pressure (MABP) had increased from 83±5 mm Hg at baseline to 97±6 mm Hg (
P
<0.05) because of a 57±20% increase in systemic vascular resistance as cardiac output decreased. In contrast, sunitinib had no discernible effects on pulmonary and coronary hemodynamics or cardiac function. We subsequently investigated the mechanisms underlying the sunitinib-induced systemic hypertension. Intravenous administration of NO synthase inhibitor
N
G
-nitro-
l
-arginine increased MABP by 24±1 mm Hg under baseline conditions, whereas it increased MABP even further after sunitinib administration (32±3 mm Hg;
P
<0.05). Reactive oxygen species scavenging with a mixture of antioxidants lowered MABP by 13±2 mm Hg before but only by 5±2 mm Hg (
P
<0.05) after sunitinib administration. However, intravenous administration of the dual endothelin A/endothelin B receptor blocker tezosentan, which did not lower MABP at baseline, completely reversed MABP to presunitinib values. These findings indicate that sunitinib produces vasoconstriction selectively in the systemic vascular bed, without affecting pulmonary or coronary circulations. The sunitinib-mediated systemic hypertension is principally attributed to an increased vasoconstrictor influence of endothelin, with no apparent contributions of a loss of NO bioavailability or increased oxidative stress.
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Affiliation(s)
- Mariëtte H.W. Kappers
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Vincent J. de Beer
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Zhichao Zhou
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - A.H. Jan Danser
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Stefan Sleijfer
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Dirk J. Duncker
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Anton H. van den Meiracker
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
| | - Daphne Merkus
- From the Division of Pharmacology and Vascular Medicine, Department of Internal Medicine (M.H.W.K., A.H.J.D., A.H.v.d.M.), Division of Experimental Cardiology, Department of Cardiology, Thoraxcenter (V.J.d.B., Z.Z., D.J.D., D.M.), and Department of Medical Oncology (S.S.), Erasmus Medical Center, Rotterdam, The Netherlands
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Yoshitomi T, Hirayama A, Nagasaki Y. The ROS scavenging and renal protective effects of pH-responsive nitroxide radical-containing nanoparticles. Biomaterials 2011; 32:8021-8. [DOI: 10.1016/j.biomaterials.2011.07.014] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Accepted: 07/05/2011] [Indexed: 12/19/2022]
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21
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Thaler S, Fiedorowicz M, Grieb P, Wypych Z, Knap N, Borowik T, Zawada K, Kaminski J, Wozniak M, Rejdak R, Zrenner E, Schuettauf F. Neuroprotective effects of tempol acyl esters against retinal ganglion cell death in a rat partial optic nerve crush model. Acta Ophthalmol 2011; 89:e555-60. [PMID: 21645284 DOI: 10.1111/j.1755-3768.2011.02180.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study is to search for more effective derivatives of the superoxide dismutase mimetic tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl). Although tempol is neuroprotective in a rat partial optic nerve crush (PONC) model, relatively high doses are required to exert this effect. METHODS Tempol acyl esters with different-length fatty acids (tempol-C4, tempol-C8, tempol-C12 and tempol-C16) were synthesized and the following properties were evaluated: water-octanol partition coefficient, liposome-liposome energy transfer, and electron paramagnetic resonance (EPR). Brown Norway rats underwent PONC and received tempol or acyl esters intraperitoneally once daily for 7 consecutive days. We then compared the effects of tempol and its four esters on retinal ganglion cell (RGC) damage using a retrograde labelling method. RESULTS The water-octanol partition coefficient increased with increasing length of attached acyl chain. However, the energy of the liposome-liposome transfer seemed to be optimal for tempol-C8 and tempol-C12. The EPR signal was very similar for all tested compounds, suggesting similar efficiency of superoxide scavenging. Partial optic nerve crush in vehicle-treated animals reduced RGC numbers by approx. 59% when compared with sham-operated eyes. Tempol did not affect RGC loss at a dose of 1 mg/kg. In contrast, at molar doses equivalent to 1 mg/kg of tempol, tempol-C8 showed a significant neuroprotective effect, whereas tempol-C4, tempol-C12 and tempol-C16 did not act neuroprotectively. CONCLUSION Manipulating the hydrophobicity of tempol seems to be a promising tool for developing more potent neuroprotectants in the PONC degeneration model. However, the resulting compounds need further pharmacological evaluation.
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Affiliation(s)
- Sebastian Thaler
- Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany.
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22
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Marushima A, Suzuki K, Nagasaki Y, Yoshitomi T, Toh K, Tsurushima H, Hirayama A, Matsumura A. Newly Synthesized Radical-Containing Nanoparticles Enhance Neuroprotection After Cerebral Ischemia-Reperfusion Injury. Neurosurgery 2011; 68:1418-25; discussion 1425-6. [DOI: 10.1227/neu.0b013e31820c02d9] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Yoshitomi T, Nagasaki Y. Nitroxyl radical-containing nanoparticles for novel nanomedicine against oxidative stress injury. Nanomedicine (Lond) 2011; 6:509-18. [DOI: 10.2217/nnm.11.13] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This article discusses the preparation and characterization of pH-sensitive nitroxyl radical-containing nanoparticles (RNPs) possessing nitroxyl radicals in the core and reactive groups on the periphery, and its biomedical application. The RNPs prepared by a self-assembling amphiphilic block copolymers composed of a hydrophilic poly(ethylene glycol) (PEG) segment and a hydrophobic poly(chloromethylstyrene) (PCMS) segment in which the chloromethyl groups were converted to 2,2,6,6-tetramethylpiperidinyloxyls (TEMPOs) via an amination of PEG-b-PCMS block copolymer with 4-amino-TEMPO are initially described. The cumulant average diameter of an RNP is approximately 40 nm, and the RNP has intense electron paramagnetic resonance signals. RNPs show a prolonged blood circulation time by the compartmentalization of nitroxyl radicals into the hydrophobic core, and disintegrate in response to a low pH environment, such as ischemic tissue, resulting in effectively scavenging reactive oxygen species due to an exposure of nitroxyl radicals from the RNP core. Thus, the RNP prepared was found to be effective for cerebral ischemia–reperfusion injury. Therefore, RNPs are promising as high-performance therapeutic nanomedicine for oxidative stress injuries.
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Affiliation(s)
- Toru Yoshitomi
- Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Ibaraki, 305-8573, Japan
- Graduate School of Pure & Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8573, Japan
| | - Yukio Nagasaki
- Satellite Laboratory, International Center for Materials Nanoarchitectonics (MANA), National Institute of Materials Science (NIMS), Tennoudai 1-1-1, Tsukuba, Ibaraki, 305-8573, Japan and Master’s School of Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, 305-8573, Japan and Center for Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Ibaraki, 305-8573, Japan
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Reeder BJ. The redox activity of hemoglobins: from physiologic functions to pathologic mechanisms. Antioxid Redox Signal 2010; 13:1087-123. [PMID: 20170402 DOI: 10.1089/ars.2009.2974] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Pentacoordinate respiratory hemoproteins such as hemoglobin and myoglobin have evolved to supply cells with oxygen. However, these respiratory heme proteins are also known to function as redox enzymes, reacting with compounds such as nitric oxide and peroxides. The recent discoveries of hexacoordinate hemoglobins in vertebrates and nonsymbiotic plants suggest that the redox activity of globins is inherent to the molecule. The uncontrolled formation of radical species resulting from such redox chemistry on respiratory hemoproteins can lead to oxidative damage and cellular toxicity. In this review, we examine the functions of various globins and the mechanisms by which these globins act as redox enzymes under physiologic conditions. Evidence that redox reactions also occur under disease conditions, leading to pathologic complications, also is examined, focusing on recent discoveries showing that the ferryl oxidation state of these hemoproteins is present in these disease states in vivo. In addition, we review the latest advances in the understanding of globin redox mechanisms and how they might affect cellular signaling pathways and how they might be controlled therapeutically or, in the case of hemoglobin-based blood substitutes, through rational design.
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Affiliation(s)
- Brandon J Reeder
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, England.
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Zhang JQ, Zhang ZW, Hui L, Tian X. Design, Synthesis and Biological Evaluation of Novel Spin-Labeled Derivatives of Podophyllotoxin. Nat Prod Commun 2010. [DOI: 10.1177/1934578x1000500214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In order to design new antitumor drugs and study the relationship between antitumor and antioxidative activity of spin-labeled derivatives of podophyllotoxin, five novel pyrroline spin-labeled 4β-N-substituted-amino acid-4′-O-demethylepipodo-phyllotoxin compounds (11a-e) (Scheme 2) were synthesized and evaluated. Their cytotoxicity against three tumor cell lines (human lung carcinoma A-549, human leukemia cell HL-60 and multiple myeloma RPMI-8226) has been evaluated using a MTT-based assay in vitro. Also, we determined malondialdehyde (MDA) in liver and kidney homogenate of SD rats by the TBA method. The five new compounds showed either superior or comparable inhibitory activity against A-549, HL-60 and RPMI-8226 cell lines compared with etoposide (VP-16, 2), and all the tested compounds showed more significant antioxidant activities than VP-16. Furthermore, the partition coefficients were measured and preliminary structure-activity relationships are presented.
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Affiliation(s)
- Jia-qiang Zhang
- State Key Laboratory of Applied Organic Chemistry Lanzhou University, Lanzhou, 730000, China
| | - Zhi-wei Zhang
- State Key Laboratory of Applied Organic Chemistry Lanzhou University, Lanzhou, 730000, China
| | - Ling Hui
- Experimental center of Medicine, Lanzhou General Hospital, Lanzhou Command, Lanzhou, 730050, China
| | - Xuan Tian
- State Key Laboratory of Applied Organic Chemistry Lanzhou University, Lanzhou, 730000, China
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Simonsen U, Christensen FH, Buus NH. The effect of tempol on endothelium-dependent vasodilatation and blood pressure. Pharmacol Ther 2009; 122:109-24. [DOI: 10.1016/j.pharmthera.2009.02.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 02/05/2009] [Indexed: 02/07/2023]
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Yasukawa K, Miyakawa R, Yao T, Tsuneyoshi M, Utsumi H. Non-invasive monitoring of redox status in mice with dextran sodium sulphate-induced colitis. Free Radic Res 2009; 43:505-13. [PMID: 19353419 DOI: 10.1080/10715760902883036] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Change of redox status is associated with colitis induced by dextran sodium sulphate (DSS). This study monitored redox status in DSS-induced colitis in mice using in vivo electron spin resonance (ESR) spectroscopy with nitroxyl probes. Colitis was induced in male ICR mice by supplementing their drinking water with 3% DSS for 3, 5 or 7 days. The ESR signal decay rate of carbamoyl-PROXYL administered into the rectum was enhanced by DSS treatment and the enhancement on day 7 was suppressed by membrane-permeable antioxidants, tiron and dimethylsulphoxide and a membrane-impermeable antioxidant, mannitol. The enhancement on day 5 was suppressed by tiron and dimethylsulphoxide, while that on day 3 was inhibited only by tiron. These results suggest that redox change occurs in or around of epithelial cells on day 7, but only intracellularly on day 5, and that redox change such as generation of less reactive radicals occurs only intracellularly on day 3.
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Affiliation(s)
- Keiji Yasukawa
- Department of Bio-functional Science, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
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Wilcox CS, Pearlman A. Chemistry and antihypertensive effects of tempol and other nitroxides. Pharmacol Rev 2009; 60:418-69. [PMID: 19112152 DOI: 10.1124/pr.108.000240] [Citation(s) in RCA: 280] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Nitroxides can undergo one- or two-electron reduction reactions to hydroxylamines or oxammonium cations, respectively, which themselves are interconvertible, thereby providing redox metabolic actions. 4-Hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (tempol) is the most extensively studied nitroxide. It is a cell membrane-permeable amphilite that dismutates superoxide catalytically, facilitates hydrogen peroxide metabolism by catalase-like actions, and limits formation of toxic hydroxyl radicals produced by Fenton reactions. It is broadly effective in detoxifying these reactive oxygen species in cell and animal studies. When administered intravenously to hypertensive rodent models, tempol caused rapid and reversible dose-dependent reductions in blood pressure in 22 of 26 studies. This was accompanied by vasodilation, increased nitric oxide activity, reduced sympathetic nervous system activity at central and peripheral sites, and enhanced potassium channel conductance in blood vessels and neurons. When administered orally or by infusion over days or weeks to hypertensive rodent models, it reduced blood pressure in 59 of 68 studies. This was accompanied by correction of salt sensitivity and endothelial dysfunction and reduced agonist-evoked oxidative stress and contractility of blood vessels, reduced renal vascular resistance, and increased renal tissue oxygen tension. Thus, tempol is broadly effective in reducing blood pressure, whether given by acute intravenous injection or by prolonged administration, in a wide range of rodent models of hypertension.
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Affiliation(s)
- Christopher S Wilcox
- Division of Nephrology and Hypertension, Kidney and Vascular Disorder Center, Georgetown University, Washington, DC 20007, USA.
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Abdallah DM, El-Abhar HS, Abdel-Aziz DH. TEMPOL, a membrane-permeable radical scavenger, attenuates gastric mucosal damage induced by ischemia/reperfusion: A key role for superoxide anion. Eur J Pharmacol 2009; 603:93-7. [DOI: 10.1016/j.ejphar.2008.11.057] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Revised: 11/12/2008] [Accepted: 11/24/2008] [Indexed: 12/15/2022]
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Lijnen P, Petrov V, van Pelt J, Fagard R. Inhibition of superoxide dismutase induces collagen production in cardiac fibroblasts. Am J Hypertens 2008; 21:1129-36. [PMID: 18756259 DOI: 10.1038/ajh.2008.242] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The aim of this study was to determine whether inhibition of superoxide dismutase (SOD) with diethyldithiocarbamic acid (DETC) could affect the collagen production, the mRNA and protein expression of collagen types I and III, and fibronectin in control and angiotensin II (ANG II)-treated cardiac fibroblasts. Its effect was compared with the SOD mimetics tempol and EUK-8 and with polyethyleneglycol (PEG)-SOD. METHODS Cardiac fibroblasts were cultured to confluence, incubated in serum-free Dulbecco's modified Eagle's medium for 24 h, preincubated with(out) the tested inhibitors for 1 h and further incubated with(out) ANG II (1 micromol/l) for 24 h. RESULTS DETC dose-dependently inhibited the activity of CuZn-SOD in cardiac fibroblasts. Superoxide anion production was increased by DETC and decreased by tempol in control and ANG II-treated fibroblasts. DETC also reduced the intracellular generation of reactive oxygen species (ROS) (such as H2O2, hydroxyl radicals, hydroperoxides) in control and ANG II-treated fibroblasts, whereas tempol reduced the ROS production only in ANG II-treated fibroblasts. ANG II and DETC stimulated the collagen production and the collagen I and fibronectin content in fibroblasts. The SOD mimetics tempol and EUK-8 as well as PEG-SOD reduced the collagen production. ANG II and DETC stimulated the tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 levels, whereas tempol decreased the TIMP-2 content in control and ANG II-treated fibroblasts. Matrix metalloproteinase (MMP)-1 level was reduced by ANG II and DETC and increased by tempol. CONCLUSION These data suggest a vital role of SOD and the formed ROS in the accumulation of collagen in cardiac fibroblasts.
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Soule BP, Hyodo F, Matsumoto KI, Simone NL, Cook JA, Krishna MC, Mitchell JB. Therapeutic and clinical applications of nitroxide compounds. Antioxid Redox Signal 2007; 9:1731-43. [PMID: 17665971 DOI: 10.1089/ars.2007.1722] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Nitroxide compounds have been used for many years as biophysical tools, but only during the past 15-20 years have the many interesting biochemical interactions been discovered and harnessed for therapeutic applications. By modifying oxidative stress and altering the redox status of tissues, nitroxides have the ability to interact with and alter many metabolic processes. This interaction can be exploited for therapeutic and research use, including protection against ionizing radiation, as probes in functional magnetic resonance imaging, cancer prevention and treatment, control of hypertension and weight, and protection from damage resulting from ischemia/reperfusion injury. Although much remains to be done, many applications have been well studied, and some are presently being tested in clinical trials. The therapeutic and research uses of nitroxides are reviewed here, with a focus on the progress from initial development to modern, state-of-the art trials.
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Affiliation(s)
- Benjamin P Soule
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892, USA.
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Chen Y, Pearlman A, Luo Z, Wilcox CS. Hydrogen peroxide mediates a transient vasorelaxation with tempol during oxidative stress. Am J Physiol Heart Circ Physiol 2007; 293:H2085-92. [PMID: 17644566 DOI: 10.1152/ajpheart.00968.2006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tempol catalyzes the formation of H(2)O(2) from superoxide and relaxes blood vessels. We tested the hypothesis that the generation of H(2)O(2) by tempol in vascular smooth muscle cells during oxidative stress contributes to the vasorelaxation. Tempol and nitroblue tetrazolium (NBT) both metabolize superoxide in vascular smooth muscle cells, but only tempol generates H(2)O(2). Rat pressurized mesenteric arteries were exposed for 20 min to the thromboxane-prostanoid receptor agonist, U-46619, or norepinephrine. During U-46619, tempol caused a transient dilation (22 +/- 2%), whereas NBT was ineffective (2 +/- 1%), and neither dilated vessels constricted with norepinephrine, which does not cause vascular oxidative stress. Neither endothelium removal nor blockade of K(+) channels with 40 mM KCl affected the tempol-induced dilation, but catalase blunted the tempol dilation by 53 +/- 7%. Tempol, but not NBT, increased H(2)O(2) in rat mesenteric vessels detected with dichlorofluorescein. To test physiological relevance in vivo, topical application of tempol caused a transient dilation (184 +/- 20%) of mouse cremaster arterioles exposed to angiotensin II for 30 min, which was not seen with NBT (9 +/- 4%). The vasodilation to tempol was reduced by 68 +/- 6% by catalase. We conclude that the transient relaxation of blood vessels by tempol after prolonged exposure to U-46619 or angiotensin II is mediated in part via production of H(2)O(2) and is largely independent of the endothelium and potassium channels.
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MESH Headings
- 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/pharmacology
- Angiotensin II/metabolism
- Animals
- Antioxidants/pharmacology
- Catalase/metabolism
- Cells, Cultured
- Cyclic N-Oxides/pharmacology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Hydrogen Peroxide/metabolism
- In Vitro Techniques
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Mice
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/enzymology
- Myocytes, Smooth Muscle/metabolism
- Nitroblue Tetrazolium/pharmacology
- Norepinephrine/pharmacology
- Oxidative Stress/drug effects
- Potassium Channels/drug effects
- Potassium Channels/metabolism
- Rats
- Rats, Inbred SHR
- Spin Labels
- Superoxide Dismutase/metabolism
- Superoxides/metabolism
- Vasoconstrictor Agents/pharmacology
- Vasodilation/drug effects
- Vasodilator Agents/pharmacology
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Affiliation(s)
- Yifan Chen
- Cardiovascular Kidney Hypertension Institute, Division of Nephrology & Hypertension, Georgetown Univ., 4000 Reservoir Road, NW, Bldg. D-399, Washington, DC 20057, USA.
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Soule BP, Hyodo F, Matsumoto KI, Simone NL, Cook JA, Krishna MC, Mitchell JB. The chemistry and biology of nitroxide compounds. Free Radic Biol Med 2007; 42:1632-50. [PMID: 17462532 PMCID: PMC1991293 DOI: 10.1016/j.freeradbiomed.2007.02.030] [Citation(s) in RCA: 381] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 02/21/2007] [Accepted: 02/27/2007] [Indexed: 02/04/2023]
Abstract
Cyclic nitroxides are a diverse group range of stable free radicals that have unique antioxidant properties. Because of their ability to interact with free radicals, they have been used for many years as biophysical tools. During the past 15-20 years, however, many interesting biochemical interactions have been discovered and harnessed for therapeutic applications. Biologically relevant effects of nitroxides have been described, including their ability to degrade superoxide and peroxide, inhibit Fenton reactions, and undergo radical-radical recombination. Cellular studies defined the activity of nitroxides in vitro. By modifying oxidative stress and altering the redox status of tissues, nitroxides have been found to interact with and alter many metabolic processes. These interactions can be exploited for therapeutic and research use, including protection against ionizing radiation, as probes in functional magnetic resonance imaging, cancer prevention and treatment, control of hypertension and weight, and protection from damage resulting from ischemia/reperfusion injury. Although much remains to be done, many applications have been well studied and some are currently being tested in clinical trials. The therapeutic and research uses of nitroxide compounds are reviewed here with a focus on the progress from initial development to modern trials.
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Affiliation(s)
- Benjamin P Soule
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
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Macias CA, Chiao JW, Xiao J, Arora DS, Tyurina YY, Delude RL, Wipf P, Kagan VE, Fink MP. Treatment with a novel hemigramicidin-TEMPO conjugate prolongs survival in a rat model of lethal hemorrhagic shock. Ann Surg 2007; 245:305-14. [PMID: 17245186 PMCID: PMC1876982 DOI: 10.1097/01.sla.0000236626.57752.8e] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We sought to develop a therapeutic agent that would permit prolongation of survival in rats subjected to lethal hemorrhagic shock (HS), even in the absence of resuscitation with asanguinous fluids or blood. METHODS AND RESULTS We synthesized a series of compounds that consist of the electron scavenger and superoxide dismutase mimic, 4-amino-2,2,6,6-tetramethylpiperidine-N-oxyl (4-NH2-TEMPO), conjugated to fragments and analogs of the membrane-active cyclopeptide antibiotic, gramicidin S. Using an in vivo assay, wherein isolated intestinal segments were loaded inside the lumen with various test compounds, we studied these compounds for their ability to prevent ileal mucosal barrier dysfunction induced by subjecting rats to profound HS for 2 hours. The most active compound in this assay, XJB-5-131, ameliorated peroxidation of the mitochondrial phospholipid, cardiolipin, in ileal mucosal samples from rats subjected to HS. XJB-5-131 also ameliorated HS-induced activation of the pro-apoptotic enzymes, caspases 3 and 7, in ileal mucosa. Intravenous treatment with XJB-5-131 (2 micromol/kg) significantly prolonged the survival of rats subjected to profound blood loss (33.5 mL/kg) despite administration of only a minimal volume of crystalloid solution (2.8 mL/kg) and the absence of blood transfusion. CONCLUSION These data support the view that mitochondrially targeted electron acceptors and SOD mimics are potentially valuable therapeutics for the treatment of serious acute conditions, such as HS, which are associated with marked tissue ischemia.
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Affiliation(s)
- Carlos A Macias
- Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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Kentner R, Safar P, Behringer W, Wu X, Henchir J, Ma L, Hsia CJC, Tisherman SA. Small volume resuscitation with tempol is detrimental during uncontrolled hemorrhagic shock in rats. Resuscitation 2007; 72:295-305. [PMID: 17112648 DOI: 10.1016/j.resuscitation.2006.05.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 05/26/2006] [Accepted: 05/26/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND In a previous study, titration of a hypertonic saline (HTS) solution during severe uncontrolled hemorrhagic shock (UHS) failed to reduce mortality. In a separate study, a novel antioxidant, polynitroxylated albumin (PNA) plus tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl), infused during shock increased long-term survival. We hypothesized that combining potent antioxidants with a hypertonic solution during UHS would preserve the logistical advantage of small volume resuscitation and improve survival. METHODS An UHS outcome model in rats was used. UHS phase I (90 min) included blood withdrawal of 30 ml/kg over 15 min, followed by tail amputation for uncontrolled bleeding. At 20 min, rats were randomized to four groups (n=10 each) for hypotensive resuscitation from 20 to 90 min (mean arterial pressure [MAP] > or = 40 mmHg): HTS/starch group received 7.2% NaCl/10% hydroxyethyl starch; HTS/albumin group received 7.5% NaCl/20% albumin; HTS/PNA group received 7.5% NaCl/20% PNA; HTS/albumin+tempol group received 7.5% NaCl/20% albumin plus tempol. Resuscitation phase II (180 min) included hemostasis, return of shed blood and administration of fluids to restore MAP > or = 80 mmHg. Observation phase III was to 72 h. RESULTS The total amount of fluid required to maintain hypotensive MAP during HS was low and did not differ between groups (range: 3.4+/-1.9 to 5.3+/-2.5 ml/kg). The rate of fluid administration required was higher in the HTS/albumin+tempol group compared to all other groups (p=0.006). Additional uncontrolled blood loss was highest in the HTS/PNA group (16.2+/-5.7 ml/kg [p=0.01] versus 10.4+/-7.9 ml/kg in the HTS/starch group, 7.7+/-5.2 ml/kg in the HTS/albumin group and 8.2+/-7.1 ml/kg in the HTS/albumin+tempol group). MAP after start of resuscitation in phase I was lower in the HTS/albumin+tempol group than the HTS/albumin or HTS/PNA groups (p<0.01). This group was also less tachycardic. Long-term survival was low in all groups (2 of 10 after HTS/starch and 1 of 10 after HTS/albumin, 3 of 10 after HTS/PNA, 1 of 10 after HTS/albumin+tempol). Median survival time was shortest in the HTS/albumin+tempol group (72 min [CI 34-190]) compared to all other groups (p=0.01). CONCLUSIONS Despite its benefits in other model systems, free tempol is potentially hazardous when combined with hypertonic fluids. PNA abrogates these deleterious effects on acute mortality but may lead to increased blood loss in the setting of UHS.
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Affiliation(s)
- Rainer Kentner
- Safar Center for Resuscitation Research, University of Pittsburgh, 3434 Fifth Avenue, Pittsburgh, PA 15260, USA
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Patel K, Chen Y, Dennehy K, Blau J, Connors S, Mendonca M, Tarpey M, Krishna M, Mitchell JB, Welch WJ, Wilcox CS. Acute antihypertensive action of nitroxides in the spontaneously hypertensive rat. Am J Physiol Regul Integr Comp Physiol 2006; 290:R37-43. [PMID: 16179488 DOI: 10.1152/ajpregu.00469.2005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tempol is an amphipathic radical nitroxide (N) that acutely reduces blood pressure (BP) and heart rate (HR) in the spontaneously hypertensive rat (SHR). We investigated the hypothesis that the response to nitroxides is determined by SOD mimetic activity or lipophilicity. Groups ( n = 6–10) of anesthetized SHRs received graded intravenous doses of Ns: tempol (T), 4-amino-tempo (AT), 4-oxo-tempo (OT), 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-1-oxyl iodide (CAT-1), 3-carbamoyl-proxyl (3-CP), or 3-carboxy-proxyl (3-CTPY). Others received native or liposomal (L) Cu/Zn SOD. T and OT are uncharged, AT is positively charged and cell-permeable, and CAT-1 is positively charged and cell-impermeable. 3-CP and 3-CTPY have five-member pyrrolidine rings, whereas T, AT, OT, and CAT-1 have six-member piperidine rings. T and AT reduced mean arterial pressure (MAP) similarly (−48 ± 2 mmHg and −55 ± 8 mmHg) but more ( P < 0.05) than OT and CAT-1. 3-CP and 3-CTPY were ineffective. The group mean change in MAP with piperidine Ns correlated with SOD activity ( r = −0.94), whereas their ED50correlated with lipophilicity ( r = 0.89). SOD and L-SOD did not lower BP acutely but reduced it after 90 min (−32 ± 5 and −31 ± 6 mmHg; P < 0.05 vs. vehicle). Pyrrolidine nitroxides are ineffective antihypertensive agents. The antihypertensive response to piperidine Ns is predicted by SOD mimetic action, and the sensitivity of response is by hydrophilicity. SOD exerts a delayed hypotensive action that is not enhanced by liposome encapsulation, suggesting it must diffuse to an extravascular site.
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Affiliation(s)
- Kinjal Patel
- Georgetown University, Division of Nephrology and Hypertension, 3800 Reservoir Rd., NW, PHC F6003, Washington, DC 20007, USA.
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Guo R, Gao XY, Wang W, Wang HJ, Zhang F, Zhang Y, Zhu GQ. Tempol reduces reperfusion-induced arrhythmias in anaesthetized rats. Pharmacol Res 2005; 52:192-8. [PMID: 15967386 DOI: 10.1016/j.phrs.2005.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 03/11/2005] [Accepted: 03/14/2005] [Indexed: 11/20/2022]
Abstract
The generation of reactive oxygen species (ROS) contributes to reperfusion-induced arrhythmias. In the present study, the antiarrhythmic effects of tempol and tiron, two membrane-permeable radical scavengers, on reperfusion-induced arrhythmias in rats in vivo were investigated. The anaesthetized rats were subjected to 5 min of left descending coronary artery (LAD) occlusion followed by 30 min of reperfusion. All rats pretreated with saline developed ventricular tachycardia (VT) and ventricular fibrillation (VF) at the onset of reperfusion, and most of the rats died from irreversible VF at the end of reperfusion. However, pretreatment with tempol (30 or 100 mg kg(-1)) 5 min before reperfusion reduced mortality, arrhythmia score and the incidence and duration of VT and VF. In the rats pretreated with high dose of tempol (100 mg kg(-1)), no VF happened and all rats were alive at the end of the experiment. The arrhythmia score was also significantly decreased compared with that of rats pretreated with saline (0.80 +/- 0.4 versus 5.6 +/- 0.4, P < 0.01). Tiron also provided nearly complete protection against reperfusion-induced arrhythmias when given 2 min before reperfusion. On the other hand, intravenous administration of tempol induced decreases in mean arterial pressure (MAP), heart rate (HR) and pressure rate index (PRI), a relative indicator of myocardial oxygen consumption. In order to determine whether the antiarrhythmic effects of tempol were secondary to the reduction of myocardial oxygen consumption, continuous electrical stimulation of the aortic depressor nerve (3 V, 10 ms and 10 Hz) was carried out in a group of rats to induce decreases in MAP, HR and PRI similar to those in the high dose of Tempol group. However, these rats did not show significant changes in the severity of reperfusion-induced arrhythmias. We conclude that both tempol and tiron significantly reduce reperfusion-induced arrhythmias in rats, and this protective action is independent of hemodynamic effects.
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Affiliation(s)
- Rui Guo
- Department of Physiology, Nanjing Medical University, 140 Hanzhong Road, Nanjing 210029, China
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Arora R, Gupta D, Chawla R, Sagar R, Sharma A, Kumar R, Prasad J, Singh S, Samanta N, Sharma RK. Radioprotection by plant products: present status and future prospects. Phytother Res 2005; 19:1-22. [PMID: 15799007 DOI: 10.1002/ptr.1605] [Citation(s) in RCA: 228] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The development of radioprotective agents has been the subject of intense research in view of their potential for use within a radiation environment, such as space exploration, radiotherapy and even nuclear war. However, no ideal, safe synthetic radioprotectors are available to date, so the search for alternative sources, including plants, has been on going for several decades. In Ayurveda, the traditional Indian system of medicine, several plants have been used to treat free radical-mediated ailments and, therefore, it is logical to expect that such plants may also render some protection against radiation damage. A systematic screening approach can provide leads to identifying potential new candidate drugs from plant sources, for mitigation of radiation injury. This article reviews some of the most promising plants, and their bioactive principles, that are widely used in traditional systems of medicine, and which have rendered significant radioprotection in both in vitro and in vivo model systems. Plants and their constituents with pharmacological activities that may be relevant to amelioration of radiation-mediated damage, including antiemetic, antiinflammatory, antioxidant, cell proliferative, wound healing and haemopoietic stimulatories are also discussed.
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Affiliation(s)
- Rajesh Arora
- Division of Radiopharmaceuticals and Radiation Biology, Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Brig. SK Mazumdar Road, Delhi-110 054, India
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Shokoji T, Fujisawa Y, Kimura S, Rahman M, Kiyomoto H, Matsubara K, Moriwaki K, Aki Y, Miyatake A, Kohno M, Abe Y, Nishiyama A. Effects of Local Administrations of Tempol and Diethyldithio-Carbamic on Peripheral Nerve Activity. Hypertension 2004; 44:236-43. [PMID: 15262907 DOI: 10.1161/01.hyp.0000136393.26777.63] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have recently shown that systemic administration of a superoxide dismutase mimetic, tempol, resulted in decreases in mean arterial pressure and heart rate along with a reduction in renal sympathetic nerve activity (RSNA). It has also been shown that these parameters are significantly increased by systemic administration of a superoxide dismutase inhibitor, diethyldithio-carbamic (DETC), indicating a potential role of reactive oxygen species in the regulation of RSNA. In this study, we examined the effects of local administrations of 4-hydroxy-2,2,6,6-tetramethylpiperidine-
N
-oxyl (tempol) and DETC on RSNA in anesthetized rats. Either tempol or DETC was directly administered onto the renal sympathetic nerves located between the electrode and ganglion. Local application of tempol (10 μL, 0.17 to 1.7 mol/L, n=6) resulted in dose-dependent decreases in integrated RSNA (by −81±6% at 1.7 mol/L) without alterations in mean arterial pressure and heart rate. In contrast, DETC (10 μL, 0.17 to 1.7 mol/L, n=6) increased RSNA dose-dependently. The responses of RSNA to tempol and DETC were significantly greater in spontaneously hypertensive rats than in normotensive rats (n=6, respectively). Local application of sodium nitroprusside (1 mmol/L) or
N
G
-nitro-
l
-arginine methyl ester (0.11 mol/L) altered neither basal RSNA nor tempol-induced reductions in RSNA (n=6 and 5, respectively). A voltage-gated potassium channel blocker, 4-aminopyridine (0.1 mol/L), significantly decreased basal RSNA (by −81±1%) and completely prevented DETC-induced increases in RSNA (n=5). These results suggest that reactive oxygen species play a role in the regulation of peripheral sympathetic nerve activity, and that at least part of this mechanism is mediated through voltage-gated potassium channels.
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Affiliation(s)
- Takatomi Shokoji
- Department of Pharmacology, Kagawa Medical University, Kita-Gun, Kagawa, Japan
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Campese VM, Ye S, Zhong H, Yanamadala V, Ye Z, Chiu J. Reactive oxygen species stimulate central and peripheral sympathetic nervous system activity. Am J Physiol Heart Circ Physiol 2004; 287:H695-703. [PMID: 15277201 DOI: 10.1152/ajpheart.00619.2003] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent studies have implicated reactive oxygen species (ROS) in the pathogenesis of hypertension and activation of the sympathetic nervous system (SNS). Because nitric oxide (NO) exerts a tonic inhibition of central SNS activity, increased production of ROS could enhance inactivation of NO and result in activation of the SNS. To test the hypothesis that ROS may modulate SNS activity, we infused Tempol (4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl), a superoxide dismutase mimetic, or vehicle either intravenously (250 microg x kg(-1) x min(-1)) or in the lateral ventricle (50 microg x kg body wt(-1) x min(-1)), and we determined the effects on blood pressure (BP), norepinephrine (NE) secretion from the posterior hypothalamus (PH) measured by the microdialysis technique, renal sympathetic nerve activity (RSNA) measured by direct microneurography, the abundance of neuronal NO synthase (nNOS)-mRNA in the PH, paraventricular nuclei (PVN), and locus coeruleus (LC) measured by RT-PCR, and the secretion of nitrate/nitrite (NO(x)) in the dialysate collected from the PH of Sprague-Dawley rats. Tempol reduced BP whether infused intravenously or intracerebroventricularly. Tempol reduced NE secretion from the PH and RSNA when infused intracerebroventricularly but raised NE secretion from the PH and RSNA when infused intravenously. The effects of intravenous Tempol on SNS activity were blunted or abolished by sinoaortic denervation. Tempol increased the abundance of nNOS in the PH, PVN, and LC when infused intracerebroventricularly, but it decreased the abundance of nNOS when infused intravenously. When given intracerebroventricularly, Tempol also reduced the concentration of NO(x) in the dialysate collected from the PH. Pretreatment with N(omega)-nitro-l-arginine methyl ester did not abolish the effects of intracerebral Tempol on BP, heart rate, NE secretion from the PH, and RSNA suggesting that the effects of Tempol on SNS activity may be in part dependent and in part independent of NO. In all, these studies support the notion that ROS may raise BP via activation of the SNS. This activation may be mediated in part by downregulation of nNOS and NO production, in part by mechanisms independent of NO. The discrepancy in results between intracerebroventricular and intravenous infusion of Tempol can be best explained by direct inhibitory actions on SNS activity when given intracerebral. By contrast, Tempol may exert direct vasodilation of the peripheral circulation and reflex activation of the SNS when given intravenously.
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Affiliation(s)
- Vito M Campese
- Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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41
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Majid DSA, Nishiyama A, Jackson KE, Castillo A. Inhibition of nitric oxide synthase enhances superoxide activity in canine kidney. Am J Physiol Regul Integr Comp Physiol 2004; 287:R27-32. [PMID: 15044181 DOI: 10.1152/ajpregu.00073.2004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To evaluate the role of a potential interaction between superoxide anion (O2−) and nitric oxide (NO) in regulating kidney function, we examined the renal responses to intra-arterial infusion of a superoxide dismutase mimetic, tempol (0.5 mg·kg−1·min−1), in anesthetized dogs treated with or without NO synthase inhibitor, Nω-nitro-l-arginine (NLA; 50 μg·kg−1·min−1). In one group of dogs ( n = 10), tempol infusion alone for 30 min before NLA infusion did not cause any significant changes in renal blood flow (RBF; 5.2 ± 0.4 to 5.0 ± 0.4 ml·min−1·g−1), glomerular filtration rate (GFR; 0.79 ± 0.04 to 0.77 ± 0.04 ml·min−1·g−1), urine flow (V; 13.6 ± 2.1 to 13.9 ± 2.5 μl·min−1·g−1), or sodium excretion (UNaV; 2.4 ± 0.3 to 2.2 ± 0.3 μmol·min−1·g−1). Interestingly, when tempol was infused in another group of dogs ( n = 12) pretreated with NLA, it caused increases in V (4.4 ± 0.4 to 9.7 ± 1.4 μl·min−1·g−1) and in UNaV (0.7 ± 0.1 to 1.3 ± 0.2 μmol·min−1·g−1) without affecting RBF or GFR. Although NO inhibition caused usual qualitative responses in both groups of dogs, the antidiuretic (47 ± 5 vs. 26 ± 4%) and antinatriuretic (67 ± 4 vs. 45 ± 11%) responses to NLA were seen much less in dogs pretreated with tempol. NLA infusion alone increased urinary excretion of 8-isoprostane (13.9 ± 2.7 to 22.8 ± 3.6 pg·min−1·g−1; n = 7), which returned to the control levels (11.6 ± 3.4 pg·min−1·g−1) during coadministration of tempol. These data suggest that NO synthase inhibition causes enhancement of endogenous O2−levels and support the hypothesis that NO plays a protective role against the actions of O2−in the kidney.
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Affiliation(s)
- Dewan S A Majid
- Dept. of Physiology, SL 39, Tulane Univ. Health Sciences Center, 1430 Tulane Ave., New Orleans, LA 70112, USA.
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Mayorov DN, Head GA, De Matteo R. Tempol Attenuates Excitatory Actions of Angiotensin II in the Rostral Ventrolateral Medulla During Emotional Stress. Hypertension 2004; 44:101-6. [PMID: 15159379 DOI: 10.1161/01.hyp.0000131290.12255.04] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Superoxide has been shown to be an important intracellular mediator of actions of angiotensin II. Recently, we found that blockade of angiotensin II type-1 receptors in the rostral ventrolateral medulla (RVLM) abrogated the pressor effect of emotional stress in rabbits. In the present study, we examined the influence of superoxide dismutase mimetics, tempol and tiron, in RVLM on cardiovascular stress response in conscious rabbits. Air-jet stress evoked a sustained increase in blood pressure (+14±2 mm Hg), tachycardia (+52±7 bpm), and renal sympathoactivation (+58±8%). Bilateral microinjections of tempol or tiron (20 nmol) into RVLM did not alter resting cardiovascular parameters, but attenuated the pressor, sympathetic, and tachycardiac response to stress by 40% to 55%. By contrast, 3-carbamoylproxyl, which is structurally close to tempol but has a lower superoxide scavenging activity, did not alter the stress response. Neither tempol nor tiron altered the sympathoexcitatory response to glutamate microinjections into RVLM or to baroreceptor unloading. Microinjections of nitric oxide synthase inhibitor
N
G
-nitro-
l
-arginine methyl ester (
l
-NAME; 10 nmol) into RVLM did not affect the stress response. Coinjections of tempol and
l
-NAME decreased the pressor response to stress by 35±3%. Tempol attenuated the pressor response to microinjection of angiotensin II into RVLM by 59±15%, whereas
l
-NAME did not alter this response. These results suggest that superoxide dismutase mimetics in RVLM attenuate, partially via a nitric oxide-independent mechanism, the pressor effect of emotional stress in rabbits. Together with our previous studies, these results also indicate that superoxide is a key mediator of excitatory actions of angiotensin II in RVLM during acute stress.
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Affiliation(s)
- Dmitry N Mayorov
- Baker Heart Research Institute, PO Box 6492, St Kilda Rd Central, Melbourne, Victoria 8008, Australia.
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43
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Buehler PW, Haney CR, Gulati A, Ma L, Hsia CJC. Polynitroxyl hemoglobin: a pharmacokinetic study of covalently bound nitroxides to hemoglobin platforms. Free Radic Biol Med 2004; 37:124-35. [PMID: 15183200 DOI: 10.1016/j.freeradbiomed.2004.04.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Revised: 03/22/2004] [Accepted: 04/02/2004] [Indexed: 11/25/2022]
Abstract
Adding antioxidant activities to hemoglobin-based oxygen carriers (HBOCs) represents a means of reducing cell-free hemoglobin-mediated oxidative cascades. We have covalently bound nitroxides, a class of antioxidant enzyme mimetics, to HBOCs. The objectives of this study were (1) to evaluate the pharmacokinetic (PK) effects of administering nitroxide covalently bound to HBOCs compared to those of free nitroxide coadministered with HBOCs and (2) to elucidate the effects of differing molecular weight HBOCs on the PK of bound nitroxide in a conscious guinea pig model of 25% blood exchange transfusion. Two HBOC platforms were used, intramolecular cross-linked hemoglobin (XLHb) and dextran polymerized/conjugated XLHb (PolyHb). Polynitroxylation was achieved by reacting 4-(2-bromoacetamido)-2,2,6,6,-tetramethylpiperidine-1-oxyl with XLHb or PolyHb to form polynitroxylated XLHb and polynitroxylated PolyHb, respectively, whereas a physical mixture of XLHb or PolyHb with 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl was prepared to reflect a molar equivalence to HBOC-bound nitroxide. Plasma concentrations of two redox states, nitroxide and hydroxylamine, were determined by electron paramagnetic resonance spectroscopy. Results are presented to illustrate the influence of covalent labeling and HBOC molecular weight on nitroxide PK. The therapeutic potential of polynitroxylation of HBOCs as it relates to observations from the current and previously reported studies is discussed.
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Affiliation(s)
- Paul W Buehler
- Department of Biopharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA
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44
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Nishiyama A, Kobori H, Fukui T, Zhang GX, Yao L, Rahman M, Hitomi H, Kiyomoto H, Shokoji T, Kimura S, Kohno M, Abe Y. Role of angiotensin II and reactive oxygen species in cyclosporine A-dependent hypertension. Hypertension 2003; 42:754-60. [PMID: 12874088 PMCID: PMC2572573 DOI: 10.1161/01.hyp.0000085195.38870.44] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Treatment with cyclosporine A (CysA), a potent immunosuppressive agent, is associated with systemic and renal vasoconstriction, leading to hypertension. The present study was conducted to elucidate the contribution of angiotensin II (Ang II) to CysA-induced hypertension and reactive oxygen species (ROS) generation. CysA (30 mg/kg per day SC), given for 3 weeks in rats, increased systolic blood pressure (SBP) from 119+/-2 to 145+/-3 mm Hg (n=7). Plasma and kidney Ang II levels were significantly higher in CysA-treated rats (136+/-10 fmol/mL and 516+/-70 fmol/g) than in vehicle-treated (1 mL olive oil) rats (76+/-10 fmol/mL and 222+/-21 fmol/g, n=7). CysA treatment increased AT1 receptor protein expression in the aorta (by 251+/-35%), whereas it was reduced in the kidney (by -32+/-4%). Superoxide anion production in aortic segments and kidney thiobarbituric acid-reactive substance (TBARS) contents were higher in CysA-treated rats (26+/-2 counts/min per milligram and 37+/-3 nmol/g) than in vehicle-treated rats (17+/-1 counts/min per milligram and 24+/-3 nmol/g). Concurrent administration of an AT1 receptor antagonist, valsartan (30 mg/kg per day, in drinking water), to CysA-treated rats (n=7) significantly decreased SBP (113+/-4 mm Hg) and prevented increases in vascular superoxide (16+/-2 counts/min per milligram) and kidney TBARS contents (21+/-3 nmol/g). Similarly, treatment with a superoxide dismutase mimetic, 4-hydroxy-2,2,6,6,-tetramethylpiperidine-N-oxyl (Tempol; 3 mmol/L in drinking water, n=7), prevented CysA-induced increases in SBP (115+/-3 mm Hg), vascular superoxide (16+/-1 counts/min per milligram), and kidney TBARS contents (19+/-2 nmol/g). These data suggest that ROS generation induced by augmented Ang II levels contributes to the development of CysA-induced hypertension.
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Affiliation(s)
- Akira Nishiyama
- Department of Pharmacology, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
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45
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Kato N, Yanaka K, Hyodo K, Homma K, Nagase S, Nose T. Stable nitroxide Tempol ameliorates brain injury by inhibiting lipid peroxidation in a rat model of transient focal cerebral ischemia. Brain Res 2003; 979:188-93. [PMID: 12850585 DOI: 10.1016/s0006-8993(03)02918-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Oxygen free radicals have been implicated in the pathogenesis of cerebral ischemia and reperfusion injury. 4-Hydroxy-2,2,6,6-tetramethylpiperidene-1-oxyl (Tempol) has been reported as a stable nitroxide and a membrane-permeable free radical scavenger. This study was performed to investigate the mechanism of Tempol in attenuating ischemia-reperfusion injury in a rat model of transient focal cerebral ischemia. We measured the cerebral 2,3-dihydroxybenzoic acid (DHBA) level as the amount of hydroxyl radical production using a microdialysis technique with salicylic acids trapping during ischemia and reperfusion. The concentration of cerebral thiobarbituric acid reactive substances (TBARS), representing the extent of lipid peroxidation by free radicals, and the area of cerebral infarction were also measured. The level of cerebral 2,3-DHBA was increased during ischemia and reperfusion, especially during the early reperfusion stage at the periphery of the infarct area (nearly 500-fold). Intravenous administration of Tempol at the time of reperfusion reduced 2,3-DHBA production (Vehicle group: 472.2+/-196.2, Tempol group: 238.3+/-77.2) and the cerebral TBARS level (Vehicle group: 541.7+/-84.7, Tempol group: 339.0+/-147.2 nmol/g), and decreased the size of the cerebral infarction (Vehicle group: 202.2+/-98.4, Tempol group: 98.5+/-13.7 mm(3)). In contrast, Tempol administered 15 min prior to reperfusion reduced neither the TBARS level nor the size of the infarction. These results indicate that Tempol administration at the time of reperfusion reduced lipid peroxidation by scavenging free radicals, resulting in a reduction of the infarct size.
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Affiliation(s)
- Noriyuki Kato
- Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, 305-8575, Ibaraki, Japan
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Abstract
The lungs are directly exposed to higher oxygen concentrations than most other tissues. Increased oxidative stress is a significant part of the pathogenesis of obstructive lung diseases such as asthma and chronic obstructive pulmonary disease, parenchymal lung diseases (e.g., idiopathic pulmonary fibrosis and lung granulomatous diseases), and lung malignancies. Lung tissue is protected against these oxidants by a variety of antioxidant mechanisms among which the superoxide dismutases (SODs) are the only ones converting superoxide radicals to hydrogen peroxide. There are three SODs: cytosolic copper-zinc, mitochondrial manganese, and extracellular SODs. These enzymes have specific distributions and functions. Their importance in protecting lung tissue has been confirmed in transgenic and knockout animal studies. Relatively few studies have been conducted on these enzymes in the normal human lung or in human lung diseases. Most human studies suggest that there is induction of manganese SOD and, possibly, extracellular SOD during inflammatory, but not fibrotic, phases of parenchymal lung diseases and that both copper-zinc SOD and manganese SOD may be downregulated in asthmatic airways. Many previous antioxidant therapies have been disappointing, but newly characterized SOD mimetics are being shown to protect against oxidant-related lung disorders in animal models.
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Abstract
The role of oxidative stress in the long-term regulation of arterial pressure, renal hemodynamics, and renal damage was studied in Dahl salt-sensitive rats. Twenty-eight Dahl S/Rapp strain rats, equipped with indwelling arterial and venous catheters, were subjected to a 3-week intravenous infusion of either low Na (0.9 mmol/d) or high Na (20.6 mmol/d) or the superoxide dismutase mimetic, 4-hydroxyl-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol), at 125 micromol x kg(-1) x h(-1) plus low Na or high Na. After 21 days, mean arterial pressure was 140+/-3 mm Hg in the high-Na group, 118+/-1 mm Hg (P<0.05) in the high-Na/Tempol group, and unchanged in the low-Na/Tempol and low-Na groups. Tempol did not change renal blood flow, glomerular filtration rate, or glomerular cross-sectional area in rats subjected to the high-Na intake but did decrease urinary protein excretion, the percentage of sclerotic glomeruli, and the kidney weight to body weight ratio. In 15 additional Dahl S rats subjected to high or low Na intake for 3 weeks, renal cortical and medullary O2*- release increased significantly in the high-Na group when compared with the low-Na group. Tempol decreased both renal cortical and medullary O2*- release in the high- and low-Na rats, but the decrease in O2*- release was greater in high-Na rats. The data suggest that oxidative stress contributes to Dahl salt-sensitive hypertension and the accompanying renal damage.
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Affiliation(s)
- Shumei Meng
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, USA
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Kwon TH, Chao DL, Malloy K, Sun D, Alessandri B, Bullock MR. Tempol, a novel stable nitroxide, reduces brain damage and free radical production, after acute subdural hematoma in the rat. J Neurotrauma 2003; 20:337-45. [PMID: 12866813 DOI: 10.1089/089771503765172291] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recent studies have shown that there is increased production of deleterious free radicals following acute subdural hematoma (ASDH). Scavenging them may therefore be of therapeutic benefit. Nitroxides are new, low molecular weight, cell permeable superoxide dismutase mimics. This study investigated the neuroprotective effect of 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol) following ASDH in the rat. Twenty-one male Sprague-Dawley rats were used in two studies: (1) a volumetric study of ischemic brain damage (n = 10); and (2) a microdialysis study measuring free radical generation after ASDH (n = 11). Ten minutes after induction of hematoma, the animals received 10 mg/kg Tempol or vehicle intravenously. In the volumetric study, 4 h after treatment, the rats were perfused, the brain removed, cut into serial 12-microm coronal sections, and stained. Ischemic areas were measured in eight predetermined stereotactic planes. In the microdialysis study, free radical production was measured using the salicylate trapping technique by quantifying 2,3-dihydrobenzoic acid (2,3-DHBA) and 2,5-DHBA using HPLC. In the volumetric study, Tempol treatment significantly reduced infarct volumes; 100.2 +/- 15.7 mm3 in Tempol-treated animals compared with 171.5 +/- 13.6 mm3 in controls (42% reduction, p = 0.0005). The microdialysis study demonstrated an early twofold increase of free radical production at 30 min, and returning to the baseline levels in controls. However, in Tempol-treated animals, this early surge was attenuated, and all measured values remained around the baseline levels throughout the experiments. Tempol thus provides significant neuroprotective effect in a rat model of ASDH, related to attenuation of superoxide radical production. The use of these low molecular weight, cell-permeable agents, which readily cross the blood-brain barrier and enter cells, thus appears indicated for acute pathologies, ASDH.
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MESH Headings
- Animals
- Antioxidants/therapeutic use
- Brain Chemistry/drug effects
- Brain Damage, Chronic/drug therapy
- Brain Damage, Chronic/etiology
- Brain Damage, Chronic/pathology
- Cyclic N-Oxides/therapeutic use
- Disease Models, Animal
- Drug Stability
- Free Radicals/analysis
- Gentisates
- Hematoma, Subdural, Acute/complications
- Hematoma, Subdural, Acute/drug therapy
- Hematoma, Subdural, Acute/pathology
- Hydroxybenzoates/analysis
- Male
- Rats
- Rats, Sprague-Dawley
- Time Factors
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Affiliation(s)
- Taek-Hyun Kwon
- Department of Neurosurgery, Korea University, Seoul, Korea
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49
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Fedeli D, Damiani E, Greci L, Littarru GP, Falcioni G. Nitroxide radicals protect against DNA damage in rat epithelial cells induced by nitric oxide, nitroxyl anion and peroxynitrite. Mutat Res 2003; 535:117-25. [PMID: 12581529 DOI: 10.1016/s1383-5718(02)00296-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In order to gain more knowledge on the antioxidant role of nitroxide radicals, in this study we investigate their possible protective action against DNA damage induced by nitric oxide (NO) and reactive nitrogen oxide species deriving from it, namely nitroxyl anion (NO(-)) and peroxynitrite (ONOO(-)). Rat trachea epithelial cells were exposed under aerobic conditions to (1) NO generated by 150 microM S-nitrosoglutathione monoethyl ester (GSNO-MEE), (2) NO(-) generated by 200 microM Angeli's salt (Na(2)N(2)O(3)) (3) ONOO(-) generated by 1mM SIN-1 (3-morpholino-sydnonimine) and (4) 100 microM synthesized ONOO(-), in the absence and presence of 5 microM of two indolinonic nitroxides synthesized by us and the piperidine nitroxide TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl). DNA damage was assessed using the comet assay-a rapid and sensitive, single-cell gel electrophoresis technique used to detect primary DNA damage in individual cells. The parameter tail moment, used as an index of DNA damage, showed that in all cases the nitroxides remarkably inhibited DNA strand breaks induced by the different nitrogen oxide species. All three nitroxides protect to the same extent, except in the case of synthesized peroxynitrite where the aromatic nitroxides 1 and 2 are more efficient than TEMPO. These findings are consistent with the antioxidant character of nitroxide compounds and give additional information on the potential implications for their use as therapeutic agents.
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Affiliation(s)
- Donatella Fedeli
- Dipartimento di Biologia MCA, Università degli Studi di Camerino, Via Camerini 2, I-62032 (MC), Camerino, Italy
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50
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Shokoji T, Nishiyama A, Fujisawa Y, Hitomi H, Kiyomoto H, Takahashi N, Kimura S, Kohno M, Abe Y. Renal sympathetic nerve responses to tempol in spontaneously hypertensive rats. Hypertension 2003; 41:266-73. [PMID: 12574093 DOI: 10.1161/01.hyp.0000049621.85474.cf] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent studies have implicated a contribution of oxidative stress to the development of hypertension. Studies were performed to determine the effects of the superoxide dismutase (SOD) mimetic 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (Tempol) on vascular superoxide production and renal sympathetic nerve activity (RSNA) in anesthetized Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). Compared with WKY rats (n=6), SHR showed a doubled vascular superoxide production, which was normalized by treatment with Tempol (3 mmol/L, n=7). In WKY rats (n=6), Tempol (30 mg/kg IV) significantly decreased mean arterial pressure (MAP) from 108+/-5 to 88+/-6 mm Hg and HR from 304+/-9 to 282+/-6 beats/min. In SHR (n=6), Tempol significantly decreased MAP from 166+/-4 to 123+/-9 mm Hg and HR from 380+/-7 to 329+/-12 beats/min. Furthermore, Tempol significantly decreased RSNA in both WKY rats and SHR. On the basis of group comparisons, the percentage decreases in MAP (-28+/-4%), HR (-16+/-3%) and integrated RSNA (-63+/-6%) in SHR were significantly greater than in WKY rats (-17+/-3%, -9+/-2%, and -30+/-4%, respectively). In SHR, changes in integrated RSNA were highly correlated with changes in MAP (r=0.85, P<0.0001) during administration of Tempol (3, 10, and 30 mg/kg IV). In both WKY rats and SHR (n=4, respectively), intracerebroventricular injection of Tempol (300 micro g/1 micro L) did not alter MAP, HR, or RSNA. Intravenous administration of a SOD inhibitor, diethyldithio-carbamic acid (30 mg/kg), significantly increased MAP, HR, and integrated RSNA in both WKY rats and SHR (n=6, respectively). These results suggest that augmented superoxide production contributes to the development of hypertension through activation of the sympathetic nervous system.
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Affiliation(s)
- Takatomi Shokoji
- Second Department of Medicine, Kagawa Medical University, Kita-Gun, Kagawa, Japan
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