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Mishra K, Alsbeih G. Appraisal of biochemical classes of radioprotectors: evidence, current status and guidelines for future development. 3 Biotech 2017; 7:292. [PMID: 28868219 DOI: 10.1007/s13205-017-0925-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 08/21/2017] [Indexed: 12/13/2022] Open
Abstract
The search for efficient radioprotective agents to protect from radiation-induced toxicity, due to planned or accidental radiation exposure, is still ongoing worldwide. Despite decades of research and development of widely different biochemical classes of natural and derivative compounds, a safe and effective radioprotector is largely unmet. In this comprehensive review, we evaluated the evidence for the radioprotective performance of classical thiols, vitamins, minerals, dietary antioxidants, phytochemicals, botanical and bacterial preparations, DNA-binding agents, cytokines, and chelators including adaptogens. Where radioprotection was demonstrated, the compounds have shown moderate dose modifying factors ranging from 1.1 to 2.7. To date, only few compounds found way to clinic with limited margin of dose prescription due to side effects. Most of these compounds (amifostine, filgratism, pegfilgrastim, sargramostim, palifermin, recombinant salmonella flagellin, Prussian blue, potassium iodide) act primarily via scavenging of free radicals, modulation of oxidative stress, signal transduction, cell proliferation or enhance radionuclide elimination. However, the gain in radioprotection remains hampered with low margin of tolerance. Future development of more effective radioprotectors requires an appropriate nontoxic compound, a model system and biomarkers of radiation exposure. These are important to test the effectiveness of radioprotection on physiological tissues during radiotherapy and field application in cases of nuclear eventualities.
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Affiliation(s)
- Krishnanand Mishra
- Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Saudi Arabia
| | - Ghazi Alsbeih
- Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Saudi Arabia
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Singh VK, Garcia M, Seed TM. A review of radiation countermeasures focusing on injury-specific medicinals and regulatory approval status: part II. Countermeasures for limited indications, internalized radionuclides, emesis, late effects, and agents demonstrating efficacy in large animals with or without FDA IND status. Int J Radiat Biol 2017; 93:870-884. [DOI: 10.1080/09553002.2017.1338782] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Vijay K. Singh
- Division of Radioprotection, Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Melissa Garcia
- Division of Radioprotection, Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Hofer M, Hoferová Z, Falk M. Pharmacological Modulation of Radiation Damage. Does It Exist a Chance for Other Substances than Hematopoietic Growth Factors and Cytokines? Int J Mol Sci 2017; 18:E1385. [PMID: 28657605 PMCID: PMC5535878 DOI: 10.3390/ijms18071385] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 06/21/2017] [Accepted: 06/26/2017] [Indexed: 02/03/2023] Open
Abstract
In recent times, cytokines and hematopoietic growth factors have been at the center of attention for many researchers trying to establish pharmacological therapeutic procedures for the treatment of radiation accident victims. Two granulocyte colony-stimulating factor-based radiation countermeasures have been approved for the treatment of the hematopoietic acute radiation syndrome. However, at the same time, many different substances with varying effects have been tested in animal studies as potential radioprotectors and mitigators of radiation damage. A wide spectrum of these substances has been studied, comprising various immunomodulators, prostaglandins, inhibitors of prostaglandin synthesis, agonists of adenosine cell receptors, herbal extracts, flavonoids, vitamins, and others. These agents are often effective, relatively non-toxic, and cheap. This review summarizes the results of animal experiments, which show the potential for some of these untraditional or new radiation countermeasures to become a part of therapeutic procedures applicable in patients with the acute radiation syndrome. The authors consider β-glucan, 5-AED (5-androstenediol), meloxicam, γ-tocotrienol, genistein, IB-MECA (N⁶-(3-iodobezyl)adenosine-5'-N-methyluronamide), Ex-RAD (4-carboxystyryl-4-chlorobenzylsulfone), and entolimod the most promising agents, with regards to their contingent use in clinical practice.
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Affiliation(s)
- Michal Hofer
- Department of Cell Biology and Radiobiology, Institute of Biophysics, v.v.i., Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic.
| | - Zuzana Hoferová
- Department of Cell Biology and Radiobiology, Institute of Biophysics, v.v.i., Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic.
| | - Martin Falk
- Department of Cell Biology and Radiobiology, Institute of Biophysics, v.v.i., Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic.
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Inami K, Okayama Y, Harada M, Morita M, Mochizuki M. Synthesis and Radical Scavenging Activity of Substituted Benzo[h]chromanols. HETEROCYCLES 2017. [DOI: 10.3987/com-17-13671] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Singh VK, Fatanmi OO, Wise SY, Newman VL, Romaine PLP, Seed TM. THE POTENTIATION OF THE RADIOPROTECTIVE EFFICACY OF TWO MEDICAL COUNTERMEASURES, GAMMA-TOCOTRIENOL AND AMIFOSTINE, BY A COMBINATION PROPHYLACTIC MODALITY. RADIATION PROTECTION DOSIMETRY 2016; 172:302-310. [PMID: 27542813 PMCID: PMC5444681 DOI: 10.1093/rpd/ncw223] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This study was designed to evaluate the possible potentiation of survival protection afforded by relatively low-dose amifostine prophylaxis against total body irradiation in combination with a protective, less toxic agent, gamma-tocotrienol (GT3). Mice were administered amifostine and/or GT3, then exposed to 9.2 Gy 60Co γ-irradiation and monitored for survival for 30 days. To investigate cytokine stimulation, mice were administered amifostine or GT3; serum samples were collected and analyzed for cytokines. Survival studies show single treatments of GT3 or amifostine significantly improved survival, compared to the vehicle, and combination treatments resulted in significantly higher survival compared to single treatments. In vivo studies with GT3 confirmed prior work indicating GT3 induces granulocyte colony-stimulating factor (G-CSF). This approach, the prophylactic combination of amifostine and GT3, which act through different mechanisms, shows promise and should be investigated further as a potential countermeasure for acute radiation syndrome.
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Affiliation(s)
- Vijay K Singh
- Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine 'America's Medical School', Services University of the Health Sciences , Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences , Bethesda, MD, USA
| | - Oluseyi O Fatanmi
- Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine 'America's Medical School', Services University of the Health Sciences , Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences , Bethesda, MD, USA
| | - Stephen Y Wise
- Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine 'America's Medical School', Services University of the Health Sciences , Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences , Bethesda, MD, USA
| | - Victoria L Newman
- Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine 'America's Medical School', Services University of the Health Sciences , Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences , Bethesda, MD, USA
| | - Patricia L P Romaine
- Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine 'America's Medical School', Services University of the Health Sciences , Bethesda, MD, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences , Bethesda, MD, USA
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Singh VK, Romaine PLP, Newman VL, Seed TM. Medical countermeasures for unwanted CBRN exposures: part II radiological and nuclear threats with review of recent countermeasure patents. Expert Opin Ther Pat 2016; 26:1399-1408. [PMID: 27610458 PMCID: PMC5152556 DOI: 10.1080/13543776.2016.1231805] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Introduction: The global threat of a chemical, biological, radiological, or nuclear (CBRN) disaster is an important priority for all government agencies involved in domestic security and public health preparedness. Radiological/nuclear (RN) attacks or accidents have become a larger focus of the United States Food and Drug administration (US FDA) over time because of their increased likeliness. Clinical signs and symptoms of a developing acute radiation syndrome (ARS) are grouped into three sub-syndromes named for the dominant organ system affected, namely the hematopoietic (H-ARS), gastrointestinal (GI-ARS), and neurovascular systems. The availability of safe and effective countermeasures against radiological/nuclear threats currently represents a significant unmet medical need. Areas covered: This article reviews the development of RN threat medical countermeasures and highlights those specific countermeasures that have been recently patented and approved following the FDA Animal Rule. Patents for such agents from 2015 have been presented. Expert opinion: Two granulocyte colony-stimulating factor (G-CSF)-based radiation countermeasures (Neupogen® (Amgen, Thousand Oaks, CA) and Neulasta® (Amgen, Thousand Oaks, CA)) have recently been approved by the FDA for treatment of H-ARS and both these agents are radiomitigators, used after radiation exposure. To date, there are no FDA-approved radioprotectors for ARS.
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Affiliation(s)
- Vijay K Singh
- a Department of Pharmacology and Molecular Therapeutics , F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences , Bethesda , MD , USA.,b Armed Forces Radiobiology Research Institute , Uniformed Services University of the Health Sciences , Bethesda , MD , USA
| | - Patricia L P Romaine
- b Armed Forces Radiobiology Research Institute , Uniformed Services University of the Health Sciences , Bethesda , MD , USA
| | - Victoria L Newman
- b Armed Forces Radiobiology Research Institute , Uniformed Services University of the Health Sciences , Bethesda , MD , USA
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