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Influence of ionizing irradiation on the antioxidant enzymes of Vicia faba L.
Aly, Amina A.,El-Beltagi, Hossam E. S.
Grasas y Aceites , 2010, DOI: 10.3989/gya.111509
Abstract: The seeds of Vicia faba L. Giza 834 were exposed to γ-irradiation at dose levels of 2.5, 5.0, 10.0 and 20.0 kGy and after that exposed to He–Ne (632.8 nm) or diode (650.0 nm) laser irradiation for 5 min. The activities of POD, APOX, CAT, SOD and GST enzymes were significantly stimulated and this stimulation reached its maximum at a dose level of 5.0 kGy for enzymes POD, APOX, CAT and SOD, but for GST enzyme at a dose level 10.0 kGy. For He- Ne laser, with or without different doses (2.5, 5.0, 10.0 and 20.0 kGy) of γ-irradiation, enzyme induction was significantly stimulated and positively correlated with the dose levels of γ-irradiation in combination with the He-Ne treatment. There was a significant increase in the concentration of MDA and this increase was more pronounced at dose level 20.0 kGy (38.2 μmol/g d.w) compared to the control (3.9 μmol/g d.w). Laser treatment by He–Ne laser or diode laser only caused a slight increase (P < 0.05) in MDA content (4.4 and 5.08 μmol/g d.w respectively) compared to the control (3.9 μmol/g d.w). H2O2 content significantly increased in all treatments and this increase reached its maximum at dose level 20.0 kGy (36.3 μmol/g d.w) compared to the control (2.3 μmol/g d.w.). On the other hand, He-Ne or diode laser treatments combined with γ-irradiation significantly decreased in comparison with γ-irradiation treatments alone. In the case of glutathione content, there were significant increases by γ-irradiation at dose levels 2.5, 5.0, 10.0 and 20.0 kGy. Furthermore, with a combination of γ-irradiation and He-Ne or diode laser, a marked increase in glutathione content was found and was more pronounced than that of gamma irradiation alone. Semillas de Vicia faba L. Giza 834 fueron expuestas a γ-irradiación a dosis de 2.5, 5.0, 10.0 y 20.0 kGy y después expuesta a una radiación laser de He–Ne (632.8 nm) o de diodo (650.0 nm) durante 5 minutos. Las actividades de las enzimas POD, APOX, CAT, SOD y GST fueron favorecidas significativamente, y éstas alcanzaron un máximo a una dosis de 5.0 kGy para las enzimas POD, APOX, CAT y SOD, y a 10.0 kGy para la enzima GST. Más aún, a diferentes dosis de γ-irradiación (2.5, 5.0, 10.0 and 20.0 kGy) con y sin laser de He-Ne, la inducción enzimática fue significativamente favorecida correlacionando positivamente con las dosis de γ-irradiación en combinación con tratamientos con laser de He-Ne. Hubo un incremento significativo en la concentración de MDA y este incremento fue más pronunciado a dosis de 20.0 kGy (38.2 μmol/g d.w) comparada con el control (3.9 μmol/g d.w). Mientras que el trata
Evaluation of Radio-Protective Effect of Melatonin on Whole Body Irradiation Induced Liver Tissue Damage  [PDF]
Alireza Shirazi,Ehsan Mihandoost,Ghazale Ghobadi,Mehran Mohseni
Cell Journal , 2013,
Abstract: Objective: Ionizing radiation interacts with biological systems to induce excessive fluxes of free radicals that attack various cellular components. Melatonin has been shown to be a direct free radical scavenger and indirect antioxidant via its stimulatory actions on the antioxidant system.The aim of this study was to evaluate the antioxidant role of melatonin against radiation-induced oxidative injury to the rat liver after whole body irradiation.Materials and Methods: In this experimental study,thirty-two rats were divided into four groups. Group 1 was the control group, group 2 only received melatonin (30 mg/kg on the first day and 30 mg/kg on the following days), group 3 only received whole body gamma irradiation of 10 Gy, and group 4 received 30 mg/kg melatonin 30 minutes prior to radiation plus whole body irradiation of 10 Gy plus 30 mg/kg melatonin daily through intraperitoneal (IP) injection for three days after irradiation. Three days after irradiation, all rats were sacrificed and their livers were excised to measure the biochemical parameters malondialdehyde (MDA) and glutathione (GSH). Each data point represents mean ± standard error on the mean (SEM) of at least eight animals per group. A one-way analysis of variance (ANOVA) was performed to compare different groups, followed by Tukey’s multiple comparison tests (p<0.05).Results: The results demonstrated that whole body irradiation induced liver tissue damage by increasing MDA levels and decreasing GSH levels. Hepatic MDA levels in irradiated rats that were treated with melatonin (30 mg/kg) were significantly decreased, while GSH levels were significantly increased, when compared to either of the control groups or the melatonin only group.Conclusion: The data suggest that administration of melatonin before and after irradiation may reduce liver damage caused by gamma irradiation.
Evaluation of Oxidant Injury Induced by Irradiation in Brain Tissues of Rats of Different Ages
Ay?e BUR??N UYUMLU,Haldun ?ükrü ERKAL,Kadir BAT?IO?LU,Meltem SER?N
Trakya Universitesi Tip Fakultesi Dergisi , 2009,
Abstract: Objectives: We aimed to evaluate the age-related changes of oxidative injury in the brain tissues of rats produced by radiotherapy that is widely used on cancer treatment.Study Design: Fifty-five male Wistar albino rats [ages of rats were 1, 4, 12 weeks (n=10) and 1 year (n=5)] were divided into four groups. Irradiation were performed on a Cobalt-60 unit using a single fraction of 8 Gy. The brain tissues were homogenized and divided into two portions. One portion was used for the measurement of the malondialdehyde (MDA). The other portion was used for the measurement of the protein concentration, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) enzyme activities. Results: The SOD activity decreased significantly in 1-week-old rats (p<0.05). The decreases in GSHPx and CAT activities were more obvious in 1-week and 1-year-old rats than that in others. No significant changes were observed in adolescent and adult rats. The MDA levels of all groups increased. The highest MDA levels were seen in 1-year-old rats (p<0.05). Conclusion: Ionizing radiation used in radiotherapy affected antioxidant systems and increased MDA levels. These changes were more in the 1-week and 1-year-old rats than in others. This can be due to incomplete development of many systems in newborn rats and the loss of physiological capacities associated with aging in 1-year-old rats.
Stability of the Antioxidant Activity of Flavonoids after Gamma Irradiation  [PDF]
Ant?nio Fernando de Melo Vaz, Marthyna Pessoa de Souza, Adriana Carla Cavalcante Malta Arg?lo, Ana Maria Mendon?a de Albuquerque Melo, Maria Luiza Vilela Oliva, Haroldo Sátiro Xavier, Luana Cassandra Breitenbach Barroso Coelho, Maria Tereza dos Santos Correia
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.25071
Abstract: Food irradiation has the purpose of destroying insects or microorganisms, thereby increasing the safety and shelf life of foods. Flavonoids are ubiquitous plant secondary products with radical scavenger ability. In the present study their antioxidant stability after gamma irradiation was evaluated. The flavonoids showed fast scavenger ability measured with the 2.2-diphenyl-1-picrylhydrazyl radical (DPPH) after high doses of radiation. The low damage caused by irra- diation on antioxidant capacity of the flavonoids shows their potential use in combating chemical oxidation of bio- molecules in irradiated foods.
The Protective Effect of Curcumin on Ionizing Radiation-induced Cataractogenesis in Rats  [cached]
Seher ?imen ?zgen,Dikmen D?kmeci,Meryem Akpolat,Hakan Karada?
Balkan Medical Journal , 2012,
Abstract: Objective: The aim of the study was to determine the protective effect of curcumin against ionizing radiation-induced cataract in the lens of rats. Material and Methods: Rats were divided into six groups. Group 1: Control, Group 2: Dimethyl sulfoxide (DMSO), Group 3: DMSO+curcumin, Group 4: Irradiation, Group 5: Irradiation+DMSO, Group 6: Irradiation+DMSO+curcumin. A 15 Gy total dose was given to 4, 5, 6 groups for radiation damage. Curcumin (100 mg/kg) was dissolved in DMSO and given by intragastric intubation for 28 days. At the end of the experiment, lenses were graded and enucleated. The lenticular activity of the antioxidant enzymes, total antioxidant and glutathione peroxidase (GSH-Px), and the malondialdehyde (MDA) were measured.Results: 100% Cataract was seen in the irradiation group. Cataract rate fell to 40% and was limited at grade 1 and 2 in the curcumin group. In the irradiation group, antioxidant enzyme levels were decreased, MDA levels were increased. There was an increase in antioxidant enzyme levels and a significant decrease in MDA in the group which was given curcumin.Conclusion: Curcumin has antioxidant and radioprotective properties and is likely to be a valuable agent for protection against ionizing radiation. Hence, it may be used as an antioxidant and radioprotector against radiation-induced cataractogenesis.
Evaluation of Anti-Oxidant Status and Radioprotective Activity of a Novel Anti-Cancer Drug in Mice  [PDF]
Raafat Yousri, Eman Noaman, Omama El Shawi, Nadia Fahmy, Maha Ghazy
Journal of Cancer Therapy (JCT) , 2011, DOI: 10.4236/jct.2011.25083
Abstract: Various approaches have been developed for diminishing the effects of radiation on normal tissues or enhancing tumor cell killing by ionizing radiation. Recently, there has been an increase in the interest in research on synthetic and/or natural radioprotective agents. An important potential use for these agents is to modify and improve the outcome of radiation therapy. The aim of this study was to examine the potential radioprotective role and antioxidant potency of the novel synthetic anticancer agent, quinoline sulfonamide (PIQSA) against tissue injury and oxidative stress induced by the exposure to gamma radiation and/or incidence of cancer in experimental animals. Mice (normal and bearing solid tumors) administered PIQSA (0.350 mg/kg body weight ip. three times a week for 21 days. At the last week of 30 days experimental period, an animal group was subjected to three successive doses of γ-radiation each of 2 Gy; another group was treated with combined administration of PIQSA 20 minutes before γ-irradiation. Some biochemical parameters (LPx, GSH, SOD, and CAT in liver homogenates, also plasma lipid profile (total lipids, total cholesterol, total triglycerides (TG), HDLc and LDLc were measured. To examine any adverse effect which could be attained by chemical treatment, liver enzymes (AST, ALT), and kidney function (creatinine and urea) were estimated in blood plasma, in addition to examination of some haematological indexes. The results indicated that the deleterious effects due to exposure to γ-radiation, and/or incidence of cancer on most of the estimated parameters could be controlled to a certain extent by administration of PIQSA to animals prior to irradiation. The results also confirmed that there were no significant adverse effects on mice due to the treatment with this chemical compound.
How Does Ionizing Irradiation Contribute to the Induction of Anti-Tumor Immunity?  [PDF]
Benjamin Frey,Udo S. Gaipl
Frontiers in Oncology , 2012, DOI: 10.3389/fonc.2012.00075
Abstract: Radiotherapy (RT) with ionizing irradiation is commonly used to locally attack tumors. It induces a stop of cancer cell proliferation and finally leads to tumor cell death. During the last years it has become more and more evident that besides a timely and locally restricted radiation-induced immune suppression, a specific immune activation against the tumor and its metastases is achievable by rendering the tumor cells visible for immune attack. The immune system is involved in tumor control and we here outline how RT induces anti-inflammation when applied in low doses and contributes in higher doses to the induction of anti-tumor immunity. We especially focus on how local irradiation induces abscopal effects. The latter are partly mediated by a systemic activation of the immune system against the individual tumor cells. Dendritic cells are the key players in the initiation and regulation of adaptive anti-tumor immune responses. They have to take up tumor antigens and consecutively present tumor peptides in the presence of appropriate co-stimulation. We review how combinations of RT with further immune stimulators such as AnnexinA5 and hyperthermia foster the dendritic cell-mediated induction of anti-tumor immune responses and present reasonable combination schemes of standard tumor therapies with immune therapies. It can be concluded that RT leads to targeted killing of the tumor cells and additionally induces non-targeted systemic immune effects. Multimodal tumor treatments should therefore tend to induce immunogenic tumor cell death forms within a tumor microenvironment that stimulates immune cells.
Serum Proteome Analysis for Profiling Predictive Protein Markers Associated with the Severity of Skin Lesions Induced by Ionizing Radiation  [PDF]
Thibault Chaze,Louis Hornez,Christophe Chambon,Iman Haddad,Joelle Vinh,Jean-Philippe Peyrat,Marc Benderitter,Olivier Guipaud
Proteomes , 2013, DOI: 10.3390/proteomes1020040
Abstract: The finding of new diagnostic and prognostic markers of local radiation injury, and particularly of the cutaneous radiation syndrome, is crucial for its medical management, in the case of both accidental exposure and radiotherapy side effects. Especially, a fast high-throughput method is still needed for triage of people accidentally exposed to ionizing radiation. In this study, we investigated the impact of localized irradiation of the skin on the early alteration of the serum proteome of mice in an effort to discover markers associated with the exposure and severity of impending damage. Using two different large-scale quantitative proteomic approaches, 2D-DIGE-MS and SELDI-TOF-MS, we performed global analyses of serum proteins collected in the clinical latency phase (days 3 and 7) from non-irradiated and locally irradiated mice exposed to high doses of 20, 40 and 80 Gy which will develop respectively erythema, moist desquamation and necrosis. Unsupervised and supervised multivariate statistical analyses (principal component analysis, partial-least square discriminant analysis and Random Forest analysis) using 2D-DIGE quantitative protein data allowed us to discriminate early between non-irradiated and irradiated animals, and between uninjured/slightly injured animals and animals that will develop severe lesions. On the other hand, despite a high number of animal replicates, PLS-DA and Random Forest analyses of SELDI-TOF-MS data failed to reveal sets of MS peaks able to discriminate between the different groups of animals. Our results show that, unlike SELDI-TOF-MS, the 2D-DIGE approach remains a powerful and promising method for the discovery of sets of proteins that could be used for the development of clinical tests for triage and the prognosis of the severity of radiation-induced skin lesions. We propose a list of 15 proteins which constitutes a set of candidate proteins for triage and prognosis of skin lesion outcomes.
Amelioration of radiation-induced skin injury by adenovirus-mediated heme oxygenase-1 (HO-1) overexpression in rats
Shuyu Zhang, Chuanjun Song, Jundong Zhou, Ling Xie, Xingjun Meng, Pengfei Liu, Jianping Cao, Xueguang Zhang, Wei-Qun Ding, Jinchang Wu
Radiation Oncology , 2012, DOI: 10.1186/1748-717x-7-4
Abstract: A control adenovirus (Ad-EGFP) and a recombinant adenovirus (Ad-HO1-EGFP) were constructed. Rats were irradiated to the buttock skin with a single dose of 45 Gy followed by a subcutaneous injection of PBS, 5 × 109 genomic copies of Ad-EGFP or Ad-HO1-EGFP (n = 8). After treatment, the skin MDA concentration, SOD activity and apoptosis were measured. The expression of antioxidant and pro-apoptotic genes was determined by RT-PCR and real-time PCR. Skin reactions were measured at regular intervals using the semi-quantitative skin injury score.Subcutaneous injection of Ad-HO1-EGFP infected both epidermal and dermal cells and could spread to the surrounding regions. Radiation exposure upregulated the transcription of the antioxidant enzyme genes, including SOD-1, GPx2 and endogenous HO-1. HO-1 overexpression decreased lipid peroxidation and inhibited the induction of ROS scavenging proteins. Moreover, HO-1 exerted an anti-apoptotic effect by suppressing FAS and FASL expression. Subcutaneous injection of Ad-HO1-EGFP demonstrated significant improvement in radiation-induced skin injury.The present study provides evidences for the protective role of HO-1 in alleviating radiation-induced skin damage in rats, which is helpful for the development of therapy for radiation-induced skin injury.Radiotherapy offers valuable alternatives to primary surgical approaches for cancer patients. Despite being a useful modality for cancer therapy, ionizing radiation may injure surrounding normal tissues [1,2]. Although the skin is not the primary target, it may be significantly injured and its function profoundly impaired during radiation therapy [3,4]. While increased efforts have led to new treatment schedules that are designed to maximize antineoplastic effects and minimize skin toxicity, radiation-induced skin injury remains a serious concern, which may limit the duration of radiation and the dose delivered. In addition, nuclear accidents are another cause of such skin reactions [5,6]. T
Relationship between growth fraction and clonogenic survival after ionizing irradiation in pancreatic MiaPaCa2 cells
Rasa Purvinien , Nijol Kazlauskait , Vydmantas Atko ius , Dainius Characiejus , Aloyza Luk ien
Acta medica Lituanica , 2009, DOI: 10.2478/v10140-009-0006-8
Abstract: Background. The prediction of cell radiosensitivity still remains a matter of great interest in the field of radiation biology and oncology. The aim of the present study was to examine the relationship between the value of growth fraction (GF) prior to irradiation and the clonogenic survival of the pancreatic cancer cell line MiaPaCa2. Materials and methods. Growth fraction prior to irradiation was determined by a novel method using bromodeoxyuridine-flow cytometry data from a single sample. The cells were irradiated with 2 and 8 Gy using a 60Co source. Cell survival after ionizing radiation was measured using a clonogenic assay. Pearson' product-moment correlation coefficient was used to estimate the correlation of GF and clonogenic survival fraction values. Results. A positive correlation between GF values and cell survival fraction was obtained after irradiation with 8 Gy (r = 0.67, P = 0.0002). We observed a trend of a higher GF and better clonogenic survival of cells after irradiation with 2 Gy. Conclusions. A higher growth fraction prior to irradiation is related to a better clonogenic survival of the pancreatic cell line MiaPaCa2. Whether or not this finding is applicable to other cell types remains to be established.
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