Radioprotective Effect of Nigella Sativa Oil on Heart Tissues of Rats Exposed to Irradition

Abstract Background Various studies are ongoing related to the radioprotective agents. Herbal preparations are currently becoming popular because of their beneficial effects with fewer side effects compared to the synthetic/semi-synthetic medicines, and Nigella sativa oil (NSO) is only one of them. Objective To investigate NSO for its antioxidant effects on the heart tissue of rats exposed to ionizing radiation (IR). Methods Thirty six male albino Wistar rats, divided into four groups, were designated to group I (IR plus NSO group) that received both 5 Gray of gamma IR to total cranium and NSO; group II (IR alone group) that received IR plus saline, group III (control group of NSO) that received saline and did not receive NSO or IR; group IV (control group) that received only sham IR. Alterations in Total antioxidant status (TAS) and Total oxidant status (TOS), Oxidative stres index (OSI), Sulhydryl group (SH), Lipid hydroperoxide (LOOH), Paraoxonase (PON) levels, Arylesterase (ARE) and Ceruloplasmin (CER) activities in homogenized heart tissue of rats were measured by biochemical methods. Results In heart tissue of the rats in the IR alone group (group II) LOOH, TOS and OSI levels were found to be higher, ARE activity and TAS level were found to be lower than all of the other groups (p < 0.01). These results also support that IR increases oxidative stress and NSO's protective effect. Conclusion NSO would reduce the oxidative damage in the irradiated heart tissue in the experimental rat model.

The radiation protection role of heparin-SOD conjugate in irradiated mice

ABSTRACT Heparin-SOD conjugate (Hep-SOD) was prepared by modifying Cu,Zn-SOD with heparin. An acute radiation-induced mouse injury model was constructed to study the radiation protection effects of Hep-SOD conjugate. Fifty-six mice were randomly divided into seven groups: (I) normal control group; (II) irradiated control group; (III) positive control group (amifostine group, 300 mg/kg); (IV) SOD group (35000 U/kg); (V) high dosage of Hep-SOD group (70000 U/kg); (VI) medium dosage of Hep-SOD group (35000 U/kg); (VII) low dosage of Hep-SOD group (17500 U/kg). Drugs were intraperitoneally injected into each mouse 1 h before radiation except for the normal control group. All the irradiated groups were irradiated with 6 Gy. Organ indices, haematopoietic function indices, peripheral blood cells, liver function test, oxidative stress state and pathological observation were detected to study the effects of Hep-SOD on irradiated mice. Results showed that bone marrow suppression of irradiated mice could be reduced when treated by Hep-SOD before radiation. Oxidative stress detection and pathological observation of the liver and intestine showed that the damage caused by radiation was relieved when mice were treated with Hep-SOD before radiation. This study shows a new direction to prevent organisms from the damage caused by radiation.

Radioiodine-induced oxidative stress in patients with differentiated thyroid carcinoma and effect of supplementation with vitamins C and E and selenium (antioxidants)

ABSTRACT Objective The objective of this study, in addition to confirming that therapy with 131I causes oxidative stress, was to evaluate the effect of supplementation with vitamins C and E and selenium on this phenomenon by measuring plasma 8-epi-PGF2a, a marker of lipid peroxidation. Subjects and methods Forty patients with thyroid cancer submitted to thyroidectomy, who received 3.7 GBq 131I after levothyroxine withdrawal, were selected; 20 patients did not receive (control group) and 20 patients received (intervention group) daily supplementation consisting of 2000 mg vitamin C, 1000 mg vitamin E and 400 µg selenium for 21 days before 131I. Plasma 8-epi-PGF2a was measured immediately before and 2 and 7 days after 131I. Results A significant increase in plasma 8-epi-PGF2a after 131I was observed in the two groups. The concentrations of 8-epi-PGF2α were significantly higher in the control group before and 2 and 7 days after 131I. The percentage of patients with elevated 8-epi-PGF2α was also significantly higher in the control group before and after 131I. Furthermore, the increase (percent) in 8-epi-PGF2α was significantly greater in the control group (average of 112.3% versus 56.3%). Only two patients (10%) reported side effects during supplementation. Conclusions Ablation with 131I causes oxidative stress which can be minimized by the use of antioxidants.

Effect of irradiation with different laser wavelengths on oxidative stress of non-hepatectomized rats

PURPOSE: To assess the effect of two laser wavelengths, either separate or combined, on intact rat livers. METHOD: Nineteen male Wistar rats (200-300 g) were submitted to laser irradiation at 5 different sites on the liver surface.Wavelengths 660 and 780 nm were used, with a dose of irradiation of 60 J/cm2/site.The animals were divided into the groups:control (C) and animals irradiated with 660 nm laser (L1), with 780 nm laser (L2) or withboth wavelengths (L3).Mitochondrial function, mitochondrial swelling, and hepatocellular malondialdehyde (MDA) levels were determined.Data were analyzed by the Mann-Whitney test, with the level of significance set at 5%. RESULTS: There was a reduction of ADP-activated respiration (state 3) in group L1 compared to group C (p=0.0016), whereas the values of group L2 were similar to control.Group L3 also showed a reduction of state 3 (p=0.0159).There was a reduction of RCR in group L1 compared to control (p=0.0001) and to group L2 (p=0.0040).Mitochondrial swelling only differed between group L3 and control (p=0.0286).There was a increase in MDA levels in group L3 compared to control (p=0.0476) and to group L2 (p=0.0286) and in group L1 compared to group L2 (p=0.0132). CONCLUSION: Although laser irradiation reduced mitochondrial function,it did not interfere with the hepatocellular energy status.

Ameliorative effect of septilin, an ayurvedic preparation against γ-irradiation-induced oxidative stress and tissue injury in rats.

Ionizing radiation is known to induce multiple organ dysfunctions directly related to an increase of cellular oxidative stress, due to overproduction of reactive oxygen species (ROS). This study was aimed to investigate the effect of septilin (an ayurvedic poly-herbal formulation containing the principal herbs, namely Commiphora wightii, Trinospora cordifolia, Rubia cardifolia, Emblica officinalis, Saussurea lappa and Glycyrrhiza glabra) against whole body γ-irradiation-induced oxidative damage in hepatic and brain tissues in rats. Administration of septilin for 5 days (100 mg/kg) prior to radiation resulted in a significant increase in both superoxide dismutase (SOD) activity and total glutathione (GSH) level in hepatic and brain tissues, while serum high-density lipoprotein-cholesterol (HDL) was reduced by γ-irradiation. Also, septilin resulted in a significant decrease in NO(x), nitric oxide and malondialdehyde (MDA) levels in hepatic and brain tissues and a significant decrease in serum triglycerides, low-density lipoprotein-cholesterol (LDL) and total cholesterol levels and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels and alkaline phosphatase (ALP), γ-glutamyl transferase (GGT) activities, as well as serum tumor necrosis factor-alpha (TNF-α), compared to irradiated group. In conclusion, data obtained from this study indicated that septilin exhibited potential antioxidant activity and showed radioprotective effect against γ-radiation by preventing oxidative stress and scavenging free radicals.

Effect of low level microwave radiation exposure on cognitive function and oxidative stress in rats.

Use of wireless communicating devices is increasing at an exponential rate in present time and is raising serious concerns about possible adverse effects of microwave (MW) radiation emitted from these devices on human health. The present study aimed to evaluate the effects of 900 MHz MW radiation exposure on cognitive function and oxidative stress in blood of Fischer rats. Animals were divided into two groups (6 animals/group): Group I (MW-exposed) and Group II (Sham-exposed). Animals were subjected to MW exposure (Frequency 900 MHz; specific absorption rate 8.4738 × 10-5 W/kg) in Gigahertz transverse electromagnetic cell (GTEM) for 30 days (2 h/day, 5 days/week). Subsequently, cognitive function and oxidative stress parameters were examined for each group. Results showed significant impairment in cognitive function and increase in oxidative stress, as evidenced by the increase in levels of MDA (a marker of lipid peroxidation) and protein carbonyl (a marker of protein oxidation) and unaltered GSH content in blood. Thus, the study demonstrated that low level MW radiation had significant effect on cognitive function and was also capable of leading to oxidative stress.

Influência do equipamento ondas curtas na produção de estresse oxidativo e capacidade antioxidante / Influence of short waves equipment in the production of oxidative stress and antioxidant capacity

Objetivo - A maioria dos estudos sobre produção de estresse oxidativo tem se voltado para a prática de exercícios aeróbios e relações com diversas patologias. Uma análise detalhada de indivíduos submetidos à radiação eletromagnética produzida pelo equipamento de ondas curtas proporcionará grande contribuição para a compreensão da relação estresse oxidativo e radiação eletromagnética. O objetivo deste estudo é avaliar a influência do campo eletromagnético emitido pelo equipamento de ondas curtas na produção de estresse oxidativo e a capacidade antioxidante de cada indivíduo. Métodos - Foram selecionados 15 indivíduos universitários, independente do gênero, de 18 a 25 anos de idade, submetidos a sessões diárias em aparelho de ondas curtas contínuas durante 15 minutos. Foi aplicado questionário, e antes e após as 10 sessões coletada uma amostra de sangue venoso, para análise e comparação dos níveis de Malondialdeído (MDA) e CapacidadeAntioxidante Total (TEAC). Resultados - Nos indivíduos em geral ocorreu aumento da média de MDA, porém nos indivíduos etilistas ocorreu um aumento significante com P=0,0432. Naqueles que incluíam em sua dieta verduras e legumes, frutas e margarina, ocorreu aumento de TEAC significante com P=0,0328, P=0,0360, P=0,0275, respectivamente. Em indivíduos que apresentaram IMC entre 24,8 - 28,0 ocorreu aumento significante de TEAC com P=0,0316. Conclusões - Conclui-se que o ondas curtas não interfere na produção de estresse oxidativo devido à ação imediata da capacidade antioxidante.

Objective - Most studies on production of oxidative stress has been returned to the practice of aerobic exercises and relations with various pathologies. A detailed analysis of individuals subjected to electromagnetic radiation produced by short wave equipment will provide great contribution to the understanding of oxidative stress and electromagnetic radiation. The purpose of this study is to assess the influence of electromagnetic emitted by short-wave equipment in the production of oxidative stress and antioxidant capacity of each individual. Methods - For this, 15 university individuals were selected, regardless of gender, from 18 to 25 years old, underwent daily sessions in short-wave equipment continued for 15 minutes. Questionnaire was applied, and before and after the 10 sessions collected a sample of venous blood for analysis and comparison of levels of Malondialdehyde (MDA) and Total Equivalente Antioxidant Capacity (TEAC). Results - In subjects in general there was an increase in average MDA, but in subjects alcohol was a significant increase with P = 0.0432. Those in their diet that included vegetables and legumes, fruits, nuts and margarine, there was significant increase in TEAC with P = 0.0328, P = 0.0360, P = 0.0275,respectively. In individuals who had BMI between 24.8 - 28.0 occurred with a significant increase of TEAC P = 0.0316. Conclusions - It was concluded that the short waves do not interfere with the production of oxidative stress due to the immediate action of antioxidant capacity.

Assessment of free radical-mediated damage in head and neck squamous cell carcinoma patients and after treatment with radiotherapy.

Reactive oxygen species (ROS) produced as a part of cellular metabolism can interact with biological macromolecules such as DNA, proteins and lipids and interfere with their normal functions, leading to the loss of cellular viability. ROS have been implicated in many pathophysiological conditions including cancer. In the present study, the damage caused by ROS and the effect of radiation in head and neck squamous cell carcinoma (HNSCC) patients were assessed in the erythrocytes by analyzing the superoxide dismutase (SOD) and catalase (CAT) activities, and levels of total thiols (T-SH) and malondialdehyde (MDA, a marker for lipid peroxidation). Blood samples were collected before the start of treatment and after the completion of radiotherapy. Both SOD and CAT activities were decreased in untreated patients, but elevated in patients after treatment. The T-SH levels were also depleted in untreated HNSCC patients, but elevated non-significantly after radiation therapy (p>0.05). The levels of MDA showed a significant increase in both untreated patients and after radiation therapy when compared with normal subjects (p<0.05). Thus, the present study indicated that the free radical-mediated damage was aggravated in untreated HNSCC patients, but the levels of antioxidants returned to baseline or nearly so after the treatment with radiation therapy.

Radio frequency electromagnetic radiation (RF-EMR) from GSM (0.9/1.8GHz) mobile phones induces oxidative stress and reduces sperm motility in rats

INTRODUCTION: Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices. OBJECTIVE: The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality. MATERIALS AND METHODS: Male albino Wistar rats (10-12 weeks old) were exposed to RF-EMR from an active GSM (0.9/1.8 GHz) mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested. RESULTS: One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis. CONCLUSION: Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility.

Melatonin prevents inflammation and oxidative stress caused by abdominopelvic and total body irradiation of rat small intestine

We investigated the day-night differences in intestinal oxidative-injury and the inflammatory response following total body (TB) or abdominopelvic (AP) irradiation, and the influence of melatonin administration on tissue injury induced by radiation. Rats (male Wistar, weighing 220-280 g) in the irradiated groups were exposed to a dose of 8 Gy to the TB or AP region in the morning (resting period - 1 h after light onset) or evening (activity span - 13 h after light onset). Vehicle or melatonin was administered immediately before, immediately after and 24 h after irradiation (10, 2.0 and 10 mg/kg, ip, respectively) to the irradiated rats. AP (P < 0.05) and TB (P < 0.05) irradiation applied in the morning caused a significant increase in thiobarbituric acid reactive substance (TBARS) levels. Melatonin treatment in the morning (P < 0.05) or evening (P < 0.05) decreased TBARS levels after TB irradiation. After AP irradiation, melatonin treatment only in the morning caused a significant decrease in TBARS levels (P < 0.05). Although we have confirmed the development of inflammation after radiotherapy by histological findings, neither AP nor TB irradiation caused any marked changes in myeloperoxidase activity in the morning or evening. Our results indicate that oxidative damage is more prominent in rats receiving TB and AP irradiation in the morning and melatonin appears to have beneficial effects on oxidative damage irrespective of the time of administration. Increased neutrophil accumulation indicates that melatonin administration exerts a protective effect on AP irradiation-induced tissue oxidative injury, especially in the morning.

Photo-oxidative damage to isolated rat liver mitochondria induced by phenothiazines

Photosensitization is a well-known side-effect of phenothiazines that could involve photochemically promoted oxidative damage to mitochondria, leading to the impairment of metabolic functions and apoptosis. In this work, for the first time, we investigated the effects of photoexcited thioridazine (TR), trifluoperazine (TFP) and fluphenazine (FP) on isolated rat liver mitochondria. Under UV irradiation, the presence of these phenothiazines led to a dose-dependent lack of the respiratory control ratio. These effects were not accompanied by significant swelling and oxidation of protein thiol groups but were accompanied by lipid peroxidation. Lycopene and sorbate, well-known quenchers of singlet oxygen and triplet species, respectively, were ineffective at protecting mitochondrial lipids against the damage promoted by the excited phenothiazines, suggesting that photochemically-produced cation radicals were the pro-oxidant species. Corroborating this proposal, butylated hydroxytoluene (BHT) completely inhibited the lipid peroxidation induced by UV irradiation in the presence of phenothiazines. These novel results make a significant contribution to the understanding of the photochemical properties of phenothiazines in biological systems

Ionizing radiation induces blockade of c-Jun N-terminal kinasedependent cell death pathway in amanner correlated with p21Cip/WAF1 induction in primary cultured normal human fibroblasts

During radiotherapy of cancer, neighboring normal cells may receive sub-lethal doses of radiation. To investigate whether such low levels of radiation modulate normal cell responses to death stimuli, primary cultured human fibroblasts were exposed to various doses of gamma-rays. Analysis of cell viability using an exclusion dye propidium iodide revealed that the irradiation up to 10 Gy killed the fibroblasts only to a minimal extent. In contrast, the cells efficiently lost their viability when exposed to 0.5-0.65 mM H2O2. This type of cell death was accompanied by JNK activation, and was reversed by the use of a JNK-specific inhibitor SP600125. Interestingly, H2O2 failed to kill the fibroblasts when these cells were pre-irradiated, 24 h before H2O2 treatment, with 0.25-0.5 Gy of gamma-rays. These cytoprotective doses of gamma-rays did not enhance cellular capacity to degrade H2O2, but elevated cellular levels of p21Cip/WAF1, a p53 target that can suppress H2O2-induced cell death by blocking JNK activation. Consistently, H2O2-induced JNK activation was dramatically suppressed in the pre-irradiated cells. The overall data suggests that ionizing radiation can impart normal fibroblasts with a survival advantage against oxidative stress by blocking the process leading to JNK activation.

Oxyradicals under UV-b stress and their quenching by antioxidants.

Formation of oxyradicals under UV-B stress was investigated using cucumber cotyledons. UV-B radiation induced production of free radicals which were analyzed by ESR spectroscopy. Evidence was obtained for the formation of superoxide and hydroxyl radicals in the tissues by comparing PBN-adducts formed with radicals obtained by chemical autooxidation of KO2 and Fenton's reaction. Addition of superoxide dismutase (SOD) to the reaction mixture partially reduced the intensity of signals confirming the production of superoxide radical as well as hydroxyl radicals. These radicals were quenched in vitro by the natural antioxidants alpha-tocopherol, ascorbic acid and benzoquinone. Changes in the level of antioxidants were also monitored under UV-B stress. The endogenous level of ascorbic acid was enhanced and alpha-tocopherol level was reduced in the tissue after exposure to UV-B radiation. The present report happens to be the first direct evidence obtained for the formation of superoxide and hydroxyl radicals in plant tissues exposed to UV-B radiation.