Gy Of Gamma Radiation Research Articles

Radioprotective effects of vitamin A against gamma radiation in mouse bone marrow cells

Radioprotectors by neutralizing the effects of free radicals, reduce the destructive effects of radiation. In this protocol article, the radioprotectory effect of vitamin A on micronuclei induced by gamma radiation was evaluated using micronucleus test. Vitamin A was injected intraperitoneally at 100 and 400 mg/kg two hours before 2 Gray (Gy) of gamma radiation. Animals were sacrificed after 24 h, and then specimens of the bone marrow were smeared and stained. The number of micronuclei were counted in polychromatic cells. Both dosage of vitamin A reduced the micronucleus in bone marrow polychromatic erythrocytes (MnPCE) level, which is statistically significant. The appropriate amount of vitamin A for protection in mice is 100 mg/kg, which protect the bone marrow of mice against clastogenic effects of radiation. The results of the study showed that vitamin A, possibly with an antioxidant mechanism, eliminates the effects of free radicals from ionizing radiation on bone marrow cells and reduces genetic damage.•The data of radioprotective effects of vitamin A showed that administration of 100 mg/kg vitamin A to mice prior to 2 Gy of gamma radiation has reduced the micronucleus levels in PCE cells by a factor of 2.62.•Administration of 100 mg/kg vitamin A, which is much smaller than LD50 of vitamin A (LD50 for intraperitoneal injection = 1510 ± 240 mg/kg) can protect mice.•Vitamin A reduces the harmful effects of ionizing radiation on DNA, due to the antioxidant activity and the trapping of free radicals produced by radiation, and diminish the genetic damage caused by radiation.•Vitamin A has no effect on the proliferation and differentiation rate of bone marrow cells.

Radioprotective effect of grape seed extract against gamma irradiation in mouse bone marrow cells.

Ionizing radiations produce free radicals which are often responsible for DNA damage or cell death. Grape seed extract (GSE) is a natural compound having an antioxidant that protects DNA, lipids, and proteins from free radical damages. In this study, radioprotective effect of the GSE has been investigated in mouse bone marrow cells using micronucleus test. Four groups of mice were investigated in this study: Mice in Group 1 were subjected to injection of distilled water with no irradiation. Mice in Group 2 were exposed to 3 Gy gamma radiation after the injection of distillated water. Mice in Group 3 were injected with 200 mg/kg of the GSE without any irradiation. In another group, mice were exposed to three gray gamma irradiation after the injection of GSE. Animals were killed, and slides were prepared from the bone marrow cells 24 h after irradiation. The slides were stained with May Grunwald-Giemsa method and analyzed microscopically. The frequency of the micronucleated polychromatic erythrocytes (MnPCEs), micronucleated normochromatic erythrocyte (MnNCEs), and polychromatic erythrocyte/polychromatic erythrocyte + normochromatic erythrocyte (PCE/PCE + NCE) ratios was calculated. Injection of GSE significantly decreased the frequency of MnPCEs (P < 0.0001) and MnNCEs (P < 0.05) and increased the ratio of PCE/PCE + NCE (P < 0.0001) compared to the irradiated control group. GSE could reduce clastogenic and cytotoxic effects of gamma irradiation in mice bone marrow cells; therefore, it can be concluded that the GSE is a herbal compound with radioprotective effects against gamma irradiation. Free radical scavenging and the antioxidant effects of the GSE probably are responsible mechanisms for the GSE radioprotective effects.

Reduction of Gamma Radiation-Induced Damage by Hydro-Alcoholic Extract of Nardostachys jatamansi.

The search for a nontoxic radioprotector has not yielded any promising results. Many antioxidant compounds, though effective under in vitro conditions as radioprotectors, have failed under in vivo settings due to their toxicity. The Indian medical system of Ayurveda uses a variety of plants with antioxidant potential, and these may be harboring molecules with radioprotective properties. In the present work, the radioprotective property of Nardostachys jatamansi was investigated. A hydro-alcoholic extract of this plant provided protection to the cellular DNA and membrane from 4 Gy gamma radiation. Depletion of cellular antioxidant status was also prevented by this extract. Molecular-level analysis in the intestines of mice revealed a lower bax/bcl2 ratio suggestive of a reduction of radiation-induced apoptosis. Expression levels of the DNA repair gene atm were elevated, along with a reduction in the expression of the inflammatory gene cox2. The extract also provided a survival advantage to mice exposed to lethal doses of gamma radiation. These results suggest a possible radioprotective role for Nardostachys jatamansi.

Novel sulfonamide benzoquinazolinones as dual EGFR/HER2 inhibitors, apoptosis inducers and radiosensitizers

A series of sulfonamide benzoquinazolinones 5–18 was synthesized and evaluated for cytotoxic activity against MDA-MB-231 cell line. The compounds showed IC50 ranging from 0.26 to 161.49 µM. The promising compounds were evaluated for their inhibitory profile against epidermal growth factor (EGFR) and HER2 enzymes. Compound 10 showed more potent activity on both EGFR and HER2 than erlotinib (IC50 3.90 and 5.40 µM versus 6.21 and 9.42 µM). The pro-apoptotic activity of 10 was evaluated against caspase-3, Bax, B-cell lymphoma protein 2 (Bcl-2) expression levels, and cell cycle analysis. Compound 10 increased the level of caspase-3 by 10 folds, Bax level by 9 folds, decreased the level of the Bcl-2 by 0.14 and arrested the cell cycle in the G2/M phase. The radio-sensitizing activity of 10 was measured using a single dose of 8 Gy gamma radiation (IC50 decreased from 0.31 to 0.22 µM). Molecular docking was performed on EGFR and HER2 receptors.

Synthesis and Characterization of Two Chiral Pyrrolyl α-Nitronyl Nitroxide Radicals and Determination of their Cytotoxicity and Radioprotective Properties in C6 Cells and Mice under Ionizing Radiation

In this study, two chiral nitronyl nitroxyl radicals, L1 and D1, were synthesized and evaluated for their potential radioprotective properties invitro and invivo. We synthesized the new stable nitronyl nitroxide radicals, L1 and D1, according to Ullman’s method, and their chemical structures were characterized using UV-vis absorption, electron spin resonance (ESR), and circular dichroism (CD) spectra. The cytotoxicity of L1 and D1 on C6 glioma cells (C6 cells) was examined using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. To study the anti-radiation effects of L1 and D1 on C6 cells, we determined the optical density (OD) values of irradiated C6 cells using the MTT assay. The effects of L1 and D1 on the survival rate of mice after radiation exposure was evaluated. To demonstrate the influence of L1 and D1 pre-treatment on the antioxidant enzyme system, we studied the activities of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and glutathione peroxidase (GSH) in mouse plasma after exposure to 6.5 Gy gamma radiation. The results showed that L1 and D1 did not have any obvious cytotoxicity at concentrations below 125μgmL−1. Moreover, L1 and D1 had the same cytotoxic effects on C6 cells. L1 and D1 significantly enhanced C6 cell survival after 8, 10, and 12 Gy radiation exposure, and there was no significant difference in the OD values between L1 and D1. The effects of these drugs on mouse survival rates were dose-dependent. Pre-treatment with different concentrations of L1, D1, or WR2721 significantly increased the activity of SOD, CAT, and GSH and significantly decreased the activity of MDA compared with radiation exposure only. In addition, the activities of SOD, CAT, and GSH in the L1 group were higher than those in the D1 group, whereas the activity of MDA was lower. Therefore, L1 and D1 have potential as safe and efficient therapeutic drugs against radiation damage.

Mitigation of radiation-induced oxidative stress by methanolic extract of Tragia involucrata in swiss albino mice

Background: Tragia involucrata L. has been used in Indian traditional medicine since centuries to treat various ailments. The plant remains unexplored for its radioprotective properties and hence the present study. Objective: The main objective of the study is to ascertain the radioprotective effects of T. involucrata methanolic extract (TME) in Swiss albino mice against whole-body gamma radiation. Materials and Methods: The acute toxicity of TME was evaluated. The optimal protective dose of TME against radiation-induced mortality in mice was determined by survival analysis using the Kaplan–Meier curves. To understand the mechanism of radioprotection, TME was tested for hematological changes and antioxidant levels in mice by injecting100 mg/kg body weight intraperitoneally for 5 days and irradiated with a sublethal dose of 6 Gy gamma radiation. Results: The lethal dose 50%/of TME was about 645.65 mg/kgbw. The pretreatment of mice with 100 mg/kgbw of TME increased its survivability to 30% compared with the radiation control group and hence is considered as a radioprotective dose. The lethal dose 50%/30% of the irradiation alone group was found to be 9 Gy and 10.35 Gy for the TME + irradiation group. Hence, the dose reduction factor was about 1.15. The radiation decreased the hematological parameters in the blood, but on pretreatment with TME (100 mg/kgbw), increase in levels was noted. The antioxidant enzyme levels in the mice liver homogenate were found to be replenished in the test group compared with the radiation control. Conclusion: The present study indicates the protective role of TME against gamma radiation-induced mortality and oxidative stress. Hence, it is proposed as a candidate for radioprotection.

Comparative efficiency of irradiation and its recurrent mutation on induced variability and population characteristics in rice (Oryza sativa L.)

The present study was carried out to elucidate the mutagenic efficiency of gamma rays (100 Gy, 150 Gy), electron beam (100 Gy, 150 Gy) used alone and in combination with EMS (30mM) as a recurrent treatment in the subsequent generation of Anna (R) 4 rice cultivar. The study was aimed to analyse the induced genetic variability, mean performance as well as population characteristics for various quantitative traits in M2 generation. The mutant lines were selected based on earliness, grain shape and yield. In general, bidirectional shift without any uniform trend was observed for all the traits except productive tillers per plant and grain weight. Recurrent EMS approach had no significant effect on earliness, however, it had significant effect on reduction of plant height (8.19 %) and productive tillers per plant (25.27 %) in EB 150Gy + EMS 30mM. Whereas 150 Gy gamma irradiation had increased effect on grains per panicle (21.99 %), panicle weight (34.73 %) and grain yield per plant (9.77 %). Though selection was exercised for desirable traits, co-efficient of variation was still higher for productive tillers per plant (31.90 %), grains per panicle (30.20 %), panicle weight (30.87 %) and grain yield per plant (31.55 %). From the mean performance and population characteristics, it is concluded that recurrent EMS mutagenic approach was less efficient than irradiation for induction of desirable changes in earliness, grain shape, grain yield and other quantitative traits.

Radiation-induced mutants with increased cane number in sugarcane variety CoJ 85

ABSTRACTCoJ 85 is an early-maturing, commercial sugarcane (Saccharum spp. complex) variety grown in Punjab, India. Farmers have adopted it because of its high sucrose content. However, it is shy in tillering and produces a low number of millable canes. It is also prone to lodging at maturity. Conventional breeding approaches are not feasible to further improve this variety, as it does not flower even under optimum tropical conditions. In this paper, we report on the use of gamma radiation-mediated in vivo mutagenesis to generate variation for cane number in CoJ 85.Contrary to general practice of irradiating tissue culture-derived calli (in vitro approach), single-bud cane setts (in vivo approach) of CoJ 85 were exposed to gamma rays to induce mutations for cane number. Our in vivo, standardized approach avoided tedious tissue culture cycles that cause undesirable somaclonal variation. Based on the germination data of buds, 25 Gy was found to be the 50% lethal dose (LD50). Thus, a mutant population of CoJ 85 was generated using 25 Gy gamma radiation and advanced to M1V2. The effects of different radiation doses were evaluated for number of tillers, number of millable canes, cane height (cm), cane weight (kg), and Brix (%) [Brix refers to total soluble solids content in juice; expressed in percentage) in the field-grown M1V2 population. A total of 38 elite mutant lines, which exhibited a significant increase in number of millable canes and Brix, were advanced for field evaluation and possible commercial use. We have demonstrated gamma rays-induced in vivo mutagenesis to be an effective method to generate stable mutants for increased cane number in CoJ 85.

Growth and Production of Brachiaria brizantha cv. MG5 in Three Difference Regrowth Phase Treated by Gamma Radiation Dose

This study was aimed to determine the effect of dose of gamma radiation of seeds on plant growth and plant production of Brachiaria brizantha cv. MG5 during 3 different growth phases. The variables measured were plant growth parameters (height and length of plant, number of leaves and tillers) and production (dry matter and organic matter productions). Data were analyzed in a 5 x 3 factorial design. The first factor was dose of gamma radiation consisted of 5 levels i.e., 0, 100, 200, 300, and 400 Gy. The second factor was regrowth phase consisted of 3 levels i.e., growth phase 1, growth phase 2, and growth phase 3. The difference between means was analyzed using Duncan’s Multiple Range Test (DMRT). The results showed that dose of gamma radiation influenced the plant growth and production (P<0.05) on different growth phases. The dose of 100 Gy gamma radiation showed the highest height and length, as well as dry matter and organic matter productions. The dose of 200 Gy gamma radiation showed the highest number of leaves and tillers. During regrowth phase 2, the grasses showed the highest of height, number of leaves and tillers, and organic matter production, while during regrowth phase 3, the grasses showed the highest length (P<0.05). There was an interaction between the dose of gamma radiation of seeds and regrowth phases on the growth and production of B. brizantha cv. MG5 (P<0.05). The dose of 100 Gy radiation of seeds and regrowth phase 2 gave the best interaction. In conclusion, the dose of 100 Gy radiation of seeds gave the best growth and production of B. brizantha cv. MG5 during regrowth phase 2.

Neuroprotective effect of quercetin against radiation-induced endoplasmic reticulum stress in neurons.

The endoplasmic reticulum (ER) plays an important role in the regulation and maintenance of cellular homeostasis. However, unresolved ER stress leads to deleterious effects by inducing the accumulation of unfolded proteins in the cell. Here we have demonstrated the protective aspects of quercetin against radiation-induced ER stress and against inflammation in primary cultured dorsal root ganglion (DRG) neurons. The mature DRG neurons were pretreated with different concentrations of quercetin (5-100 μM) for 24 hours before 2 Gy gamma radiation exposure and then subjected to a cytotoxicity assay, quantitative real-time polymerase chain reaction and Western blot analysis. The results showed that quercetin decreased the expression of BiP and C/EBP-homologous protein, the ER stress marker genes along with downregulation of tumor necrosis factor-α, JNK in irradiated DRG neurons. Furthermore, quercetin pretreatment significantly increased the cytoskeletal protein Tuj1 and the neurotrophin brain-derived neurotrophic factor in the neuron. These results indicate that quercetin plays a neuroprotective role against radiation-mediated ER stress and inflammatory responses.

The investigation of the combined effects of gamma irradiation and environmental manipulation on mortality and sterility of Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae)

Abstract With respect to the limitations use of methyl bromide and phosphine, employing ionizing radiation to control stored product pests has attracted great attention. The aim of this study is the investigation of the combined effects of gamma irradiation as viable alternatives to synthetic insecticides and environmental management on mortality and sterility of Rhyzopertha dominica (Fabricius) in a wheat cultivar (Gascogen). The effect of doses range from 30 to 2000 Gy gamma irradiation in combination with manipulation of temperature (15, 21, 27 and 32 °C) and relative humidity (20%, 50%, 65% and 85%) on 5–10 days old adults of R. dominica in Gascogen cultivar of wheat were explored. The experiments were repeated three times and conducted in The Nuclear Agriculture Research School in Karaj and laboratory of shahid steki silo in shahre-kord. Probit analysis revealed that both temperature and relative humidity had combined effects when used with gamma irradiation. The lowest doses of gamma ray required to kill 25% (14.2 Gy) and 50% (610.8 Gy) of the population (LD25 and LD50) were recorded at 21 °C and 85% relative humidity respectively. The low dose for 99% mortality (LD99; 2386.7 Gy) was recorded for beetles maintained at 21 °C and 50% relative humidity. The effect of temperature (15, 21, 27 and 32 °C) on sterility caused by gamma irradiation was also investigated. The results showed that the F1 generation emerged only when the beetles were treated with doses of 0–100 Gy at 32 °C and 0–70 Gy at 27 °C. These results indicate that temperature and relative humidity play an important role in the susceptibility of the lesser grain beetle to gamma irradiation. The results suggest that controlling the efficiency of gamma radiation through environmental control allows the use of low doses of gamma radiation that have a less harmful effect on human health, non-target organisms and seed agronomic features.

Low Irradiation Dose for Sorghum Seed Sterilization: Hydroponic Fodder System and In Vitro Study

The purpose of this study was to to evaluate the influence of low gamma irradiation dose on growth performance, in vitro gas production and rumen fermentation product of sorghum hydroponic fodder (SHF) to utilize them in ruminant diets. Three polyethylene packages of Samurai 2 sorghum seeds were exposed at 25oC gamma irradiation in gamma cell (Co-60) at doses of 100, 200 and 300 Gy in the presence of air. Samples were then referigated (&lt; 5oC) before planting. All seeds were planted in nutrient film technique hydroponic system. This study used Completely Randomized Design with four replications The observed parameters were total fresh yield, plant height and coversion ratio from seeds to SHF. In vitro gas test evaluation was done to compare all treatments with sorghum straw. The observed parameters were total gas production, kinetics gas, CH4 concentration, CO2 concentration and rumen fermentation products. Results showed that lower irradiation dose for seeds sterilization decreased plant height and total fresh yield on SHF production. In vitro total gas production of all SHF treatment was higher (p&lt;0.05) than sorghum straw (control) at 2-48 h time of incubation. Gamma irradiation dose of 200 and 300 Gy on SHF seeds sterilization decreased (p&lt;0.05) in vitro CH4 concentration for 19.51 and 15.43% respectively compared to SHF control (hypochlorite sterilization). In the same dose, seeds sterilization with gamma irradiation increased (p&lt;0.05) CO2:CH4 ratio by 23.46 and 20.73% respectively compared to SHF control. The treatment of 100 Gy gamma irradiation for seed sterilization also increased (p&lt;0.05) TVFA by 30.63% compared to sorghum straw. It was concluded that lower irradiation dose for seeds sterilization decreased growth performance of SHF. However, 100 Gy gamma irradiation increased in vitro total gas production.

Biochemical Role of Folic Acid Loaded Magnetic Nanoparticles Versus Gamma Irradiation in Rats

Gamma radiation produces numerous biological perturbations in cells by direct ionization of DNA and cellular targets and by indirect effect through damage by free radical production. The present study has been carried out to investigate the possible therapeutic effect of folic acid loaded magnetic nanoparticles through injection after body gamma irradiation of rats. We have shown that the folic acid loaded magnetic nanoparticles administration reduced the risk factors induced by γ -radiation. 60 male albino rats of about 130-150 g live body weight were divided into six groups, Negative control (n=10), Magnetic control (n=10), folic acid loaded Magnetic NPs control (n=10), and 6 Gy irradiation group (n=10).Three post irradiation groups where these groups exposed firstly to 6 Gy gamma irradiation then injected (I.p) by magnetite NPs, and folic acid loaded magnetic NPs, twice weekly for three weeks. The rats in all groups were anaesthetized, decapitated,the liverwas excised immediately, and frozen at -80 0c. DNA damage in rat hepatocytes were determined by comet assay, and determined cholesterol and triglyceride concentration. Results showed that whole body gamma irradiation of rats at 6Gy (single dose) induced significant increase in DNA damage (P < 0.05) that was indicated by increase in tail length, tail DNA% and tail moment as compared to control group. And significant increase in the hepatic cholesterol and triglycerides levels was observed after three weeks post-irradiation Administration of folic acid loaded magnetic iron oxide (Fe3O4) after irradiation induced significant improvement of the DNA damage and hepatic cholesterol and triglyceride level. These results indicate the role of folic acid loaded MNPs as a radio protector agent. Further, we also report the radio protective property of folic acid loaded MNPs as demonstrated by reduction in the radiation induced DNA damage, which was measured by alkaline comet assay.

RADIOPROTECTION OF ALOE VERA AGAINST BIOCHEMICAL ALTERATIONS IN SWISS ALBINO MICE

Objective: In this study, radioprotection against radiation-induced hepatic damage in Swiss Albino Mice has been observed by Aloe vera. When individuals are exposed, the radiation energy is absorbed by the biological systems, which causes radiolysis of tissue water and generates free radicals.Methods: Animals were given Aloe vera leaf extract orally 1000 mg/kg body weight/day for 15 consecutive days before radiation exposure 0.5, 3 and 5.5 Gy gamma radiation. Mice were autopsied at day ¼, 1, 3, 5,10 and 20 after irradiation to evaluate the radio modulator effect in terms of LPO and GSH.Results: Radiation treatment showed a decrease in GSH content and an increase of LPO in control set animals, however, the animals of experimental group i.e. Aloe vera and radiation combined group showed a significant increase in GSH content and decrease in LPO but values remained below normal.Conclusion: The result of present study suggests that Aloe vera has a radioprotective effect due to their antioxidant and radical scavenging activity.

Molecular characterization of induced mutation of jewawut (Setaria italica ssp. italica) from Buru Island, Indonesia using SRAP

Yulita KS, Ridwan. 2018. Molecular characterization of induced mutation of jewawut (Setaria italica ssp. italica) from Buru Island, Indonesia using SRAP. Biodiversitas 19: 1160-1168. Jewawut (Setaria italica ssp. italica) or foxtail millet is minor crops domesticated and consumed only in few parts of Sulawesi, Maluku and East Nusa Tenggara, while in other region such as Java, it is known as food for bird despite the fact that jewawut is rich in fiber. The utilization of jewawut as an alternative crop was limited due to their small size of seeds as well low yield. An effort to improve the potency of jewawut as an alternative food is through genetic improvement by induced mutation. This present study was aimed to determinate mutant of jewawut from Buru Island irradiated by gamma rays as potential genotype to produce high grain yield. Two variants of jewawut were recorded from Buru Island, red and yellow variant each referring to the colour of their seeds. Samples were consisted of 26 red and 24 of yellow variant. Mutant was detected by molecular characterization using SRAP marker. UPGMA cluster analysis was also performed to ensure the position of mutant within the UPGMA dendrogram against the control samples. Mutant with the most distinct genyotypes for yellow variant are accession O1O2#10 treated in 100 Gy and O1E1#10 treated in 200 Gy gamma radiation, whereas in the red variant are accessions O2C4#13 treated in 50 Gy and O2E4#6 treated in 200 Gy gamma radiation. All the mutants have random agronomic performances relative to controls. Mutants with potential high grain yield are O2B2#14 treated in 25 Gy for the red variant, and this should be used as a candidate to develop superior genotype.

In vitro, induction of salt tolerant potato (solanum tuberosum l.) Plants with gamma irradiation and characterization of genetic variations through sds-page and issr-pcr analysis

Salt tolerant mutants of potato (Solanum tuberosum L. ‘Sponta’) were obtained via gamma irradiation. bud explants of two strains of potato (Sponta and lady rosetta were treated with various dosages of gamma irradiation, and the clonal generations were developed. Selection of salt-tolerant mutants was accomplished by in vitro selection media containing 30, 60, 90 and 120 mM NaCl. Molecular-level differences between the control and mutant plants were elucidated using ISSR technique, and the polymorphism rate according to the selected primers was calculated as 89.66%. Genetic distances between the controls and mutants were also calculated, and related dendrograms were produced. On average the mutants were genetically 27.5% different from the control plants. The greatest difference encountered between the control and mutants was 47%, which was detected in mutant plants produced by 20 or 30 Gy gamma irradiation and regenerated in selection medium containing 100 mM NaCl.

Fractal analysis of chromatin as a potential indicator of human exposures to ionizing radiation

The theory of fractals, proposed by the mathematician Mandelbrot (1975), has been applied to many fields in Biology, mainly due to the property of self-similarity observed in the natural world, such as in the DNA molecule and chromatin structure. Many researches have proven the applicability of this mathematical analysis for the identification of cells containing mutations, in the case of cancers, or due to exposures to chemicals and ultraviolet radiation, but until the present moment, no work was done with ionizing radiation. The aim of the present study was to investigate the use of fractal analysis for the identification of irradiated cells, and to discuss its potential use as an indicator of human exposures to ionizing radiation. For this, 200 cells were digitalized, where 100 were from a blood sample irradiated with an absorbed dose of 3 Gy of gamma radiation, and 100cells were non-irradiated. Fractal dimensions (FD) were calculated by the method of Box-Counting. It was possible to notice an increase in FDs of chromatin after exposure to ionizing radiation, and an overdispersion of the values of FD only in irradiated sample. Also, when the data was reorganized in crescent order, it was possible to clearly distinct the irradiated sample from the non-irradiated one. With this, we present an efficient method for the identification of irradiated human blood samples, in a fast and most simplified way, what can be of valuable importance in cases where there is a need of quick responses to human exposures to ionizing radiation.

Assessment of squalene eligibility in bettering some maternal and fetal disorders instigated by gamma irradiation of rats at mid gestation

Purpose: Squalene is an eminent vital part of the synthesis of steroid hormones in the body as well as the first specific intermediate in cholesterol biosynthesis that plays an essential role in normal embryogenesis. The present work was designed to test the maternal and embryonic response to the modulating capacity of squalene (0.4 ml/kg/d), when supplemented to rats from days 1 to 18 of pregnancy, against the damaging consequences induced by maternal subjection to 3 Gy gamma irradiation on day 10 post-conception.Materials and methods: The experimental protocol comprised of four different pregnant groups, namely: (1) control, (2) squalene supplemented, (3) irradiated and (4) squalene supplemented + irradiated.Results: It has been detected that radiation has increased the maternal blood lactate dehydrogenase (as a marker of tissue injury), cholesterol, triglycerides, estradiol and progesterone and has also provoked the oxidative stress that has been demonstrated by the increased malondialdehyde (MDA) and the decreased glutathione (GSH) and superoxide dismutase (SOD). These maternal changes were associated with high embryonic lethality, growth retardation, severe developmental abnormalities and defective neural tube closure expressed by exencephaly. However, squalene treatment has significantly improved the radiation imposed maternal variations and reduced the embryonic mortality, although it has not been able to attenuate the embryonic neural tube defects.Conclusions: It has been presumed that the maternal mid-gestational irradiation (day 10) has affected the fetal nervous system development with concomitant maternal oxidative stress, hyperlipidemia, and increased progesterone and estradiol levels. Squalene uptake has improved the maternal variations and reduced the embryonic mortality while could not stop or improve the embryonic neural tube defects imposed by radiation at this exact radiation timing.

Radioprotective and immunomodulatory effects of Mesua ferrea (Linn.) from Western Ghats of India., in irradiated Swiss albino mice and splenic lymphocytes

The present study reports the efficacy of Mesua ferrea (Linn.) extract in mitigating radiation induced toxicity along with immunomodulatory property. Swiss albino mice, splenic lymphocytes and plasmid pBR322 DNA were used to evaluate the radioprotective effect by exposing them to 6Gy EBR or 4 Gy gamma radiation. In this study, Mesua ferrea methanolic (MfM) or aqueous extracts (MfA) significantly protected pBR322 DNA against radiation induced strand breaks. Both the extracts significantly offered protection against radiation-induced apoptosis as indicated by propidium iodide staining and DNA ladder assay. MfM or MfA significantly scavenged radiation derived free radicals indicating their antioxidant potential. MfM or MfA were orally administered to Swiss albino mice at 250 or200 mg/kg body weight respectively for 7 days. The study showed significant increase in the levels of glutathione, and activities of endogenous antioxidant enzymes superoxide dismutase & catalase. Administration of MfA or MfM to mice significantly reduced electron beam radiation (EBR; 6Gy) induced increase in MDA levels. Immunomodulatory efficacy of MfM and MfA was evaluated using concanavalin-A (Con-A) induced proliferation of CFSE labelled splenic lymphocytes. Both the extracts significantly reduced proliferation in a dose-dependent manner. Further, MfM or MfA treatment prevented EBR induced histopathological changes in jejunum, spleen, liver and kidney. This demonstrates that the plant Mesua ferrea has promising antioxidant, radioprotective and immunomodulatory activity which may be attributed to the active constituents present in it.

The effect of curcumin on lipid peroxidation and selected antioxidants in irradiated rats

The effect of irradiation on oxidants and antioxidants in selected tissues and a possible protective effect of curcumin on these indices were investigated. A total of 28 rats were divided into 3 groups; group 1 was control; group 2 was the irradiation group, saline was administered intraperiotenally (i.p.) for three days and then, 9 Gy gamma irradiation was applied; group 3 was the irradiation + curcumin group: curcumin was given i.p. for three days at 200 mg/kg body weight and then the same dose of irradiation was applied. A significant increase in malondialdehyde (MDA) was detected in the liver, kidney, and brain tissues of the rats as a result of irradiation (P&lt; 0.01). Glutathione peroxidase (GSH-Px) activity in all the tissues (except for kidneys) decreased (P&lt; 0.01), liver SOD (superoxide dismutase) activity decreased (P&lt; 0.05), and GSH (glutathione) levels in kidney and ovary tissues (P&lt; 0.001) significantly increased. While curcumin administration returned the increased MDA levels in the kidneys and brain in result of irradiation to normal (P&lt; 0.01), it did not return the increased MDA levels in the liver tissue to normal (P&lt; 0.001) despite significantly reducing them. While decreased GSH-Px and SOD activity in the liver in result of irradiation increased with the addition of curcumin (P&lt; 0.05), increased GSH levels in the kidneys and ovaries returned to control levels (P&lt; 0.001). When MDA values were examined, it was found that the addition of curcumin protected the liver, kidneys and brain from the oxidative damage caused by irradiation.