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Journal of Radiological Protection :... Feb 2022Radioprotectors are agents that have the potential to act against radiation damage to cells. These are equally invaluable in radiation protection, both in intentional... (Review)
Review
Radioprotectors are agents that have the potential to act against radiation damage to cells. These are equally invaluable in radiation protection, both in intentional and unintentional radiation exposure. It is however, complex to use a universal radioprotector that could be beneficial in diverse contexts such as in radiotherapy, nuclear accidents, and space travel, as each of these circumstances have unique requirements. In a clinical setting such as in radiotherapy, a radioprotector is used to increase the efficacy of cancer treatment. The protective agent must act against radiation damage selectively in normal healthy cells while enhancing the radiation damage imparted on cancer cells. In the context of radiotherapy, plant-based compounds offer a more reliable solution over synthetic ones as the former are less expensive, less toxic, possess synergistic phytochemical activity, and are environmentally friendly. Phytochemicals with both radioprotective and anticancer properties may enhance the treatment efficacy by two-fold. Hence, plant based radioprotective agents offer a promising field to progress forward, and to expand the boundaries of radiation protection. This review is an account on radioprotective properties of phytochemicals and complications encountered in the development of the ideal radioprotector to be used as an adjunct in radiotherapy.
Topics: Plants; Radiation Exposure; Radiation Protection; Radiation-Protective Agents
PubMed: 35130534
DOI: 10.1088/1361-6498/ac5295 -
Environmental Science and Pollution... Sep 2020Protection of normal tissues against ionizing radiation-induced damages is a critical issue in clinical and environmental radiobiology. One of the ways of accomplishing...
Protection of normal tissues against ionizing radiation-induced damages is a critical issue in clinical and environmental radiobiology. One of the ways of accomplishing radiation protection is through the use of radioprotectors. In the search for the most effective radioprotective agent, factors such as toxicity, effect on tumors, number of tissues protected, ease of administration, long-term stability, and compatibility with other drugs need to be assessed. Thus, in the present study, we systematically review existing studies on a chemical radioprotector, Ex-RAD, with the aim of examining its efficacy of radiation protection as well as underlying mechanisms. To this end, a systematic search of the electronic databases including Pubmed, Scopus, Embase, and Google Scholar was conducted to retrieve articles investigating the radioprotective effect of Ex-RAD. From an initial search of 268 articles, and after removal of duplicates as well as applying the predetermined inclusion and exclusion criteria, 10 articles were finally included for this systematic review. Findings from the reviewed studies indicated that Ex-RAD showed potentials for effective radioprotection of the studied organs with no side effect. Furthermore, the inhibition of apoptosis through p53 signaling pathway was the main mechanism of radioprotection by Ex-RAD. However, its radioprotective effect would need to be investigated for more organs in future studies.
Topics: Radiation Protection; Radiation, Ionizing; Radiation-Protective Agents; Sulfonamides
PubMed: 32583118
DOI: 10.1007/s11356-020-09618-y -
International Journal of Radiation... Aug 2012The purpose of this study was to conduct research in mice to determine the radioprotective effects of troxerutin. Thirty-day survival, oxidative status and histological...
PURPOSE
The purpose of this study was to conduct research in mice to determine the radioprotective effects of troxerutin. Thirty-day survival, oxidative status and histological changes in the liver were all evaluated.
MATERIALS AND METHODS
Troxerutin was administered orally to mice for six days before irradiation with different doses (6, 7, 8 and 10 Gy) of γ-rays and the mice were observed for 30 days after radiation to calculate 30-day survival and median lethal dose of 30 days (LD50/30). Its radioprotective efficacy was compared with the positive drug amifostine which is currently the most effective radioprotector. The animals pretreated with troxerutin for 6 days were sacrificed on day 11 after radiation (6 Gy) in order to make 10% homogenate and histological sections of liver. Antioxidant enzymes were detected in strict accordance with kit requirements. Histological liver sections were examined by hematoxylin-eosin (HE) staining.
RESULTS
Pretreatment with troxerutin resulted in a significantly higher 30-day survival rate for 70% of mice compared with 30% of irradiation group after exposure to a potentially lethal dose of 8 Gy; LD50/30 of drug treatment group was 9 Gy compared with 7.7 Gy for irradiation group. The results indicated that troxerutin increased the activity of various antioxidant enzymes, such as superoxide dismutase (SOD) in mice liver, which was reduced by radiation treatment. Maleic dialdehyde (MDA) levels were significantly reduced by troxerutin, which was increased after 6 Gy radiation. These results were further confirmed by histopathological examinations which indicated that pre-administration with the effective dose of troxerutin reduced the hepatic damage induced by radiation.
CONCLUSIONS
Administration of troxerutin before irradiation, provided higher survival of experimental mice, improvement of biochemical parameters, and preserved major histological parameters of the liver. These results collectively indicate that troxerutin is an effective radioprotective agent.
Topics: Animals; Antioxidants; Gamma Rays; Hydroxyethylrutoside; Lethal Dose 50; Liver; Male; Mice; Mice, Inbred BALB C; Oxidative Stress; Radiation-Protective Agents; Survival Analysis
PubMed: 22571496
DOI: 10.3109/09553002.2012.692494 -
International Journal of... May 1992AS101 [ammonium-trichloro (0,0' dioxyethylene)tellurate] is a new immunomodulator shown previously to stimulate the production of various cytokines in vitro and in vivo,...
AS101 [ammonium-trichloro (0,0' dioxyethylene)tellurate] is a new immunomodulator shown previously to stimulate the production of various cytokines in vitro and in vivo, and to have minimal toxicity. In the present study we explore the possibility of oral administration of AS101 to mice via cannulation in lieu of interperitoneal or intravenous administration reported to date. Our studies show that oral administration of AS101 at a dose ranging between 50 and 100 micrograms/mouse promotes hemopoietic regeneration after treatment with sublethal doses of cyclophosphamide (CYP) and protects mice from the lethal effects of this compound. In addition, AS101 administered orally confers a strong radioprotective effect upon mice when given before irradiation.
Topics: Adjuvants, Immunologic; Administration, Oral; Animals; Cell Survival; Cyclophosphamide; Ethylenes; Interleukin-2; Male; Mice; Mice, Inbred BALB C; Radiation-Protective Agents; Spleen; Survival Rate; Tellurium
PubMed: 1521929
DOI: 10.1016/0192-0561(92)90122-2 -
Arhiv Za Higijenu Rada I Toksikologiju Dec 1993The diminished probability of strategic nuclear confrontation alleviates some of the global concerns about large numbers of radiation casualties in the event of a... (Review)
Review
The diminished probability of strategic nuclear confrontation alleviates some of the global concerns about large numbers of radiation casualties in the event of a nuclear war. As a result of the protection of the environment, the management of smaller numbers of radiation casualties assumes a more predictable and more specific role confined to accidents in nuclear energy projects, industry, technology and science. Recent experience of the consequences of accidents in nuclear power plants, in the field of radiotherapy and in the disposal of radioactive waste and spent fuel, present the medical and scientific communities with formidable problems if such events are to lead to minimal adverse effects on the biosphere. Whereas it is not possible to predict a nuclear or radiation accident, radioprotection is hardly an issue of health science alone, but rather an issue of the strictest quality assurance in all aspects of the utilization of nuclear energy and ionizing radiation. Thus, the medical community concerned with radioprotection will have to confine its emphasis on the management of radiation-induced alterations of the human organism from acute radiation syndromes to the stochastic concepts of chronic alterations of radiosensitive organic systems. Current multidisciplinary research in the field of radioprotection involves all aspects of basic and clinical research ranging from the subatomic mechanisms of free radical formation, macromolecular and intracellular radiation-induced alterations, biochemical and physiological homeostatic mechanisms and organ level manifestations to the clinical management of radiation casualties in a controlled hospital environment. Radioprotective agents, although widely studied in the past four decades and including several thousand agents, have not reached the level of providing the field of medicine with an agent that conforms to all criteria of an optimal radioprotectant, including effectiveness, toxicity, availability, specificity and tolerance. This article discusses the current state of radioprotection in medical therapy, and emphasizes a need for continued research in the area of medical management of radiation casualties from the viewpoint of a realistic probability of nuclear incidents or accidents in the nuclear energy-dependent world at the end of the millennium.
Topics: Animals; Humans; Radiation Injuries; Radiation-Protective Agents
PubMed: 8192608
DOI: No ID Found -
European Journal of Histochemistry : EJH Dec 2012The aim of this study was to improve knowledge about histamine radioprotective potential investigating its effect on reducing ionising radiation-induced injury and...
The aim of this study was to improve knowledge about histamine radioprotective potential investigating its effect on reducing ionising radiation-induced injury and genotoxic damage on the rat small intestine and uterus. Forty 10-week-old male and 40 female Sprague-Dawley rats were divided into 4 groups. Histamine and histamine-5Gy groups received a daily subcutaneous histamine injection (0.1 mg/kg) starting 24 h before irradiation. Histamine-5Gy and untreated-5Gy groups were irradiated with a dose of whole-body Cesium-137 irradiation. Three days after irradiation animals were sacrificed and tissues were removed, fixed, and stained with haematoxylin and eosin, and histological characteristics were evaluated. Proliferation, apoptosis and oxidative DNA markers were studied by immunohistochemistry, while micronucleus assay was performed to evaluate chromosomal damage. Histamine treatment reduced radiation-induced mucosal atrophy, oedema and vascular damage produced by ionising radiation, increasing the number of crypts per circumference (239 ± 12 vs 160 ± 10; P<0.01). This effect was associated with a reduction of radiation-induced intestinal crypts apoptosis. Additionally, histamine decreased the frequency of micronuclei formation and also significantly attenuated 8-OHdG immunoreactivity, a marker of DNA oxidative damage. Furthermore, radiation induced flattening of the endometrial surface, depletion of deep glands and reduced mitosis, effects that were completely blocked by histamine treatment. The expression of a proliferation marker in uterine luminal and glandular cells was markedly stimulated in histamine treated and irradiated rats. The obtained evidences indicate that histamine is a potential candidate as a safe radioprotective agent that might increase the therapeutic index of radiotherapy for intra-abdominal and pelvic cancers. However, its efficacy needs to be carefully investigated in prospective clinical trials.
Topics: Animals; Apoptosis; Cell Proliferation; DNA Damage; Female; Histamine; Immunohistochemistry; Intestine, Small; Male; Radiation-Protective Agents; Rats; Rats, Sprague-Dawley; Uterus; Whole-Body Irradiation
PubMed: 23361244
DOI: 10.4081/ejh.2012.e48 -
PloS One 2024To mitigate the risk of radioactive isotope dissemination, the development of preventative and curative measures is of particular interest. For mass treatment, the...
Enhancing radioprotection: A chitosan-based chelating polymer is a versatile radioprotective agent for prophylactic and therapeutic interventions against radionuclide contamination.
To mitigate the risk of radioactive isotope dissemination, the development of preventative and curative measures is of particular interest. For mass treatment, the developed solution must be easily administered, preferably orally, with effective, nontoxic decorporating properties against a wide range of radioactive isotopes. Currently, most orally administered chelation therapy products are quickly absorbed into the blood circulation, where chelation of the radioactive isotope is a race against time due to the short circulation half-life of the therapeutic. This report presents an alternative therapeutic approach by using a functionalized chitosan (chitosan@DOTAGA) with chelating properties that remains within the gastrointestinal tract and is eliminated in feces, that can protect against ingested radioactive isotopes. The polymer shows important in vitro chelation properties towards different metallic cations of importance, including (Cs(I), Ir(III), Th(IV), Tl(I), Sr(II), U(VI) and Co(II)), at different pH (from 1 to 7) representing the different environments in the gastrointestinal tract. An in vivo proof of concept is presented on a rodent model of uranium contamination following an oral administration of Chitosan@DOTAGA. The polymer partially prevents the accumulation of uranium within the kidneys (providing a protective effect) and completely prevents its uptake by the spleen.
Topics: Chitosan; Uranium; Radiation-Protective Agents; Polymers; Chelating Agents
PubMed: 38568898
DOI: 10.1371/journal.pone.0292414 -
Physica Medica : PM : An International... Jun 2014The radioprotective effects of Dragon's blood (DB) and its extracts (DBE) were investigated using the chromosomal aberrant test, micronucleus and oxidative stress assay...
PURPOSE
The radioprotective effects of Dragon's blood (DB) and its extracts (DBE) were investigated using the chromosomal aberrant test, micronucleus and oxidative stress assay for anti-clastogenic and anti-oxidative activity.
MATERIALS AND METHODS
Adult BALB/C mice were exposed to the whole body irradiation with 4 Gy (60)Co γ-rays. DB and DBE were administered orally once a day from 5 days prior to irradiation treatment to 1 day after irradiation. The mice were sacrificed on 24 h after irradiation. The cells of bone marrow were measured by counting different types of chromosomal aberrations and the frequency of micronuclei. Oxidative stress response was carried out by analysis of serum from blood.
RESULTS
DB and DBE significantly decreased the number of bone marrow cells with chromosome aberrations after irradiation with respect to irradiated alone group. The administration of DB and DBE also significantly reduced the frequencies of micronucleated polychromatic erythrocytes (MPCE) and micronucleated normochromatic erythrocytes (MNCE). In addition, DB and DBE markedly increased the activity of antioxidant enzymes and the level of antioxidant molecular. Malondialdehyde (MDA) and nitric oxide (NO) levels in serum were significantly reduced by DB and DBE treatment.
CONCLUSIONS
Our data suggested that DB and DBE have potential radioprotective properties in mouse bone marrow after (60)Co γ-ray exposure, which support their candidature as a potential radioprotective agent.
Topics: Animals; Bone Marrow Cells; Chromosome Aberrations; DNA Damage; Gamma Rays; Male; Mice; Mice, Inbred BALB C; Micronucleus Tests; Oxidative Stress; Plant Extracts; Radiation-Protective Agents
PubMed: 24360838
DOI: 10.1016/j.ejmp.2013.12.001 -
The West Indian Medical Journal Mar 2010Most ionizing radiation-induced damage is caused by radical oxygen species (ROS). Some radioprotectors, such as amifostine, exert radioprotective effects by scavenging...
Most ionizing radiation-induced damage is caused by radical oxygen species (ROS). Some radioprotectors, such as amifostine, exert radioprotective effects by scavenging radical oxygen species. Recent studies show that hydrogen (H) has antioxidant activities that protect the brain and intestine against ischaemia-reperfusion injury and stroke by selectively reducing hydroxyl and peroxynitrite radicals. However it is seldom regarded as a radioprotective agent. In like manner we hypothesize that hydrogen may be an effective, specific and novel radioprotective agent. But H2 is explosive, while hydrogen-rich solution (solution such as physiological saline saturated with molecular hydrogen) is safer.
Topics: Antioxidants; Humans; Hydrogen; Radiation-Protective Agents
PubMed: 21275114
DOI: No ID Found -
Archives of Pharmacal Research Aug 2022Sometimes, people can be exposed to moderate or high doses of radiation accidentally or through the environment. Radiation can cause great harm to several systems within... (Review)
Review
Sometimes, people can be exposed to moderate or high doses of radiation accidentally or through the environment. Radiation can cause great harm to several systems within organisms, especially the hematopoietic system. Several types of drugs protect the hematopoietic system against radiation damage in different ways. They can be classified as "synthetic drugs" and "natural compounds." Their cellular mechanisms to protect organisms from radiation damage include free radical-scavenging, anti-oxidation, reducing genotoxicity and apoptosis, and alleviating suppression of the bone marrow. These topics have been reviewed to provide new ideas for the development and research of drugs alleviating radiation-induced damage to the hematopoietic system.
Topics: Apoptosis; Bone Marrow; DNA Damage; Hematopoietic System; Humans; Oxidation-Reduction; Radiation-Protective Agents
PubMed: 35951164
DOI: 10.1007/s12272-022-01400-7