Gy Of Gamma Radiation Research Articles

Effect of low dose ionizing radiation versus human wharton’s jelly mesenchymal stem cells in the treatment of experimental rheumatoid arthritis

Rheumatoid arthritis (RA) is one of the major causes of disability that aggrieve a financial burden for the healthcare system as well as for patients. Both stem cell therapy and low-dose radiotherapy (LD-RT) have been recognized as alternative approaches to alleviate pain, inflammation, and bone in the inflamed joints. Accordingly, the present study was designed to compare the efficacy of both modalities in the treatment of RA in experimental rats. Rheumatoid arthritis was induced in forty female rats using Complete Freund’s adjuvant (CFA), divided into four groups (arthritic induction group and three treatment groups) compared to controls: one of the treatment groups received Human’s Wharton Jelly Mesenchymal Stem Cells (WJMSC), and the other two groups received individual doses of 0.5 and 1 Gy of Gamma irradiation once a week for six weeks. After six weeks animals were sacrificed and examined for joint histology, paw swelling, mRNA gene expression for TNF-α, IL-1β and IL-6 together with serum anticyclic citrullinated peptide (anti-CCP) and nitric oxide (NO). Results showed that both doses of (0.5 Gy and 1 Gy) and WJMSC individually modulated RA effects by significantly decreasing the measured biochemical and molecular parameters. However, at the histology level it was evident that irradiation has a better pronounced effect compared to WJMSC, which showed aggravated effects on joint erosion. The present study reports that both IR and WJMSC significantly decreased Anti-CCP, which is a specific marker for RA, however, WJMSC might have deliberate effects on the synovitis and arthritis.

Cynodon dactylon alleviates radiation-induced behavioral and biochemical changes in the cerebral cortex of mice

Cynodon dactylon is herb with its rich antioxidant phytoconstituents it has been widely used in traditional medicine. The present study was aimed to investigate the ameliorative role of hydro alcoholic extract of Cynodon dactylon on cerebral cortex in the mice exposed to lethal dose of radiation. Swiss albino mice were treated with 0.25 and 1 g/kg body weight of Cynodon dactylon extract (CDE) via oral gavage for 7 days and subjected to 5 Gy of gamma radiation. All mice were subjected to behavioral and cognitive functions tests. Further, potent markers of radiation including biochemical parameters were evaluated in the cerebral cortex. Mice irradiated with γ- rays displayed a significant decline in the behavior and cognitive functions. Further, decline in antioxidant status and increase in the oxidative stress markers was observed. Pretreatment of hydroalcoholic extract of Cynodon dactylon before exposure to γ-radiation showed significant improvement in the cognitive and behavioral analysis. Further, increase in antioxidant status and a decline in level of oxidative stress markers was observed. The present study confirms the potent protective role of Cynodon dactylon on radiation induced oxidative damage to the cerebral cortex.

Sterilizing of Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) irradiated in pupa stage

Worldwide the loss of stored grain is a problem of economic order of importance, in view of the concern of the increased supply of food for a world population increasingly expanding. Associated with this fact, there is the problem of nutritional deficiency due to lack of protein, especially for the less privileged populations in the resources of a country. This lack could be met by adequate supply of grain produced, requiring for it, a system that provides optimum grain storage conditions in securing the quality until the time of consumption. The use of radiation in stored grain can solve the problem of the losses in these products, as it does not induce resistance of insects and leaves no toxic residue to the consumer, and is considered an effective and safe method. The aim of the experiment was to determine the sterilizing dose of ionizing radiation from cobalt-60 to Alphitobius diaperinus (Panzer, 1797)(Coleoptera: Tenebrionidae) in peanuts irradiated in pupa stage. The experiment was conducted in the laboratory of Radiobiology and Environment of the Center for Nuclear Energy in Agriculture - CENA / USP., Piracicaba, SP, Brazil. Peanuts samples infested with pupae of A. diaperinus were utilized in the experiment that consisted of 8 treatments with 5 repetitions. Each repetition consisted of 20 pupae a total of 100 individuals per treatment. Were irradiated with doses of 0 (control), 25, 50, 75, 100, 125, 150 and 175 Gy, in a source of cobalt-60, Gammacell-220 type, with a rate dose of 381Gy / h. The experiment was conducted in a room with temperatures of 25 ± 5 ° C and relative humidity of 70 ± 5%. After of irradiation process was evaluated of the number of emerged adult insects in each repetition in the treatments. The results show that the sterilizing dose in F1 generation was 125 Gy and the pupa lethal dose 150 Gy. The dose of 150 Gy of gamma radiation can be used as phytosanitary treatment to control of immature stages of A. diaperinus infested peanuts.

In-vitro study of the radioprotective effect of palladium α-lipoic acid nano-complex on hemoglobin molecule

This work is intended to study the radioprotective effect of palladium α-lipoic acid nano-complex (PLAC) on hemoglobin molecule in vitro. Blood samples were obtained from adult male rats weighing 120–150 g after dissection, using heparinized needles. Each blood sample was divided into four groups; the first group was kept untreated as control, palladium α-lipoic acid (PLAC) was added to the second group at concentration 2% v/v, the third group was exposed to 100 Gy gamma radiation and the forth group was irradiated with the addition of PLAC. Hemoglobin was extracted and prepared for measurement. The effects on the hemoglobin molecule were evaluated by FTIR and UV–visible spectroscopy. The results showed that PLAC increases the optical energy gap of the transition of the amino acid side chains and affects the spatial distribution of the globin part. Gamma radiation affects mainly the globin part, results in unfolding of the protein structure and perturbation in the relative orientation of the transition dipole moments. Addition of PLAC to the blood samples prior to irradiation was shown to provide protective effects which can be attributed to its ability to neutralize the free radicals.

Optimization of gamma radiation dose for induction of mutations in okra

ABSTRACT Wide variability does not exist in okra [Abelmoschus esculentus (L.) Moench], requiring induction of genetic variability. Mutagenesis creates desired variability among genotypes without altering the agronomic base which is sometimes difficult to induce using other breeding methods. Seed germination/seedling emergence and seedling growth were evaluated under laboratory and field conditions by imposing 300 to 1000 Gy (Gray, the SI unit of radiation) gamma radiation to determine median lethal (LD50) and median growth reduction (GR50) doses with Co60gamma rays. The LD50 and GR50 doses varied for both growing conditions. More than 80% of seed exposed to the LD50 dose of gamma radiation in the laboratory did not emerge under field condition. The LD50 and GR50 doses of gamma radiation determined under field condition exhibited close correspondence and presented a reliable picture regarding lethality and injury in the M1 generation (the first generation from the irradiated seed). The R2 for the linear model for seedling emergence, shoot and root length, fresh and dry weight of seedlings under field condition were 0.908, 0.902, 0.911, 0.983 and 0.972, respectively. Determination of the LD50/GR50 is important to optimize the radiation dose to isolate desired utilizable mutants. Dose optimization should be determined through use of LD50 and GR50 under field condition. The gamma radiation dose between 350 Gy and 450 Gy was optimum to create desirable mutants in okra. The optimal dose could induce a higher rate of mutation with little biological damage in succeeding generations of okra.

Evaluation of Laser Bio speckle as a new tool to detect exposure to ionizing radiation: A new dosimetric approach

Everyone in the world is exposed continuously to radiation. Exposure to ionizing radiation is known to have lethal effects in blood cells and other body organs and tissues. This work aimed to describe a new and simple method to evaluate the effect of chronic versus acute doses of ionizing radiation (IR) on animal blood model by the laser bio speckle measurements.The study concerned the biological effect for three groups of rats including control, chronically and acutely exposed to 1 Gy of gamma irradiation using Cesium-137 source. The blood samples of the three groups were then smeared over glass slides homogenously and fixed for further analysis. The bio-speckle images were produced using a coherent laser beam of green wavelengths 532.0 nm with output power < 50 mW illuminating the blood slides of the irradiated animals. Laser bio-speckle contrast measurements was used to detect the change in speckle pattern to visualize the change in blood components due to the deformation in shape and number of cells. Digital images are taken for each group samples. The chronic and acute dose reduction of the hemoglobin, hematocrit, red cell count, creatinine in serum were (8.4 vs. 16.5), (7.2 vs. 18.4), (12.1 vs. 20.7), (12.5 vs. 23.2) respectively. The components of blood that showed no specific trend observed between chronic versus acute exposure were white cell count (83.2 vs. 49.9), total protein (7.0 vs. 3.8), MCV (−5.2 vs. −3.1), MCH (−4.4 vs. −5.6), MCHC (0.69 vs. −2.1), RDW (−13.9 vs. −4.9).The study pointed that ionized radiation causes a change in blood structure components in a dose-delivery dependent manner. While this finding is expected, the capability shown by bio-speckle patterns to be consistent with mode of radiation delivery is an interesting finding that might drive the scientific community for potential future applications. From the graph representing the relation between the dose delivery and laser bio speckle contrast, it appeared that there is a direct relationship between the response of some blood components and magnitude of laser bio speckle contrast. Thus, it highly suggestive of transferring the concept of bio-speckle to other organs and tissues. Further studies are recommended to establish the relationship not only between blood components but other molecular signatures and the measurement of laser bio speckle.

Transcriptome of rhesus macaque (Macaca mulatta) exposed to total-body irradiation

The field of biodosimetry has seen a paradigm shift towards an increased use of molecular phenotyping technologies including omics and miRNA, in addition to conventional cytogenetic techniques. Here, we have used a nonhuman primate (NHP) model to study the impact of gamma-irradiation on alterations in blood-based gene expression. With a goal to delineate radiation induced changes in gene expression, we followed eight NHPs for 60 days after exposure to 6.5 Gy gamma-radiation for survival outcomes. Analysis of differential gene expression in response to radiation exposure yielded 26,944 dysregulated genes that were not significantly impacted by sex. Further analysis showed an increased association of several pathways including IL-3 signaling, ephrin receptor signaling, ErbB signaling, nitric oxide signaling in the cardiovascular system, Wnt/β-catenin signaling, and inflammasome pathway, which were associated with positive survival outcomes in NHPs after acute exposure to radiation. This study provides novel insights into major pathways and networks involved in radiation-induced injuries that may identify biomarkers for radiation injury.

Calcitriol Revises Aromatase Gene Expression in Ehrlich Solid Tumor Bearing Mice Exposed to Low Dose Gamma Radiation

Background: Dysregulation of aromatase expression had been monitored in many types of cancer. Our study aimed to evaluate the possible role of calcitriol (Cal; Vit D3-OH) or/and low dose of gamma radiation in regulation of aromatase gene expression and the regression of tumor proliferation in murine model (EST; Ehrlich solid tumor bearing mice). Methods: Mice with ≈1 cm3 EST were received (i.p. injection) day after day repeated doses of Calcitriol (Cal) (0.05µg/mouse) for 14day or/and exposed to 0.5 Gy gamma radiation (low dose) delivered as one shot at dose rate 0.48 Gy/min. Results: Our results demonstrated that, mRNA expression of aromatase, levels of cyclooxygenase (COX2) and prostaglandin (PGE2) in addition to volume of the tumor are significantly decreased while caspase 3 level is significantly increased in EST mice treated with Cal or/and exposed to 0.5 Gy gamma ray compared to untreated EST bearing mice. However, the most pronounced improvements in all of the measured parameters were obviously indicated in EST mice group treated with Cal and exposed to gamma radiation. This was accomplished by suppression of inflammatory markers which cause down regulation in aromatase mRNA expression as well as augmenting apoptosis by inducing Caspase3 concentration. Conclusion: It could be concluded that the exposure to low dose gamma radiation potentiate the action of Calcitriol against tumor growth in the subjected murine model which represent a prospective policy for the management of solid tumor and decreasing the possibilities of tumor drug resistance.

Synthesis of some quinazolinones inspired from the natural alkaloid L-norephedrine as EGFR inhibitors and radiosensitizers

A set of quinazolinones synthesized by the aid of L-norephedrine was assembled to generate novel analogues as potential anticancer and radiosensitizing agents. The new compounds were evaluated for their cytotoxic activity against MDA-MB-231, MCF-7, HepG-2, HCT-116 cancer cell lines and EGFR inhibitory activity. The most active compounds 5 and 6 were screened against MCF-10A normal cell line and displayed lower toxic effects. They proved their relative safety with high selectivity towards MDA-MB-231 breast cancer cell line. Measurement of the radiosensitizing activity for 5 and 6 revealed that they could sensitize the tumour cells after being exposed to a single dose of 8 Gy gamma radiation. Compound 5 was able to induce apoptosis and arrest the cell cycle at the G2-M phase. Molecular docking of 5 and 6 in the active site of EGFR was performed to gain insight into the binding interactions with the key amino acids.

Immunostimulating, proapoptotic and synergistic effects of propolis and its main constituent (chrysin) on the tumor growth and the cell sensitivity to ionizing radiation in mice

The increased interest in new approaches to the immunotherapy of cancer and a considerable demand for therapeutic agents which can modulate the several forms of immunodeficiency have encouraged studies on the immunomodulatory mechanisms of natural and synthetic substances. The present work was an endeavor to evaluate the imunostimulating as well as proapoptotic and synergistic effects of Chrysin (Ch) and Propolis (P) on the tumor growth and the cell sensitivity to ionizing radiation targeting the improvement of cancer therapeutic protocols. Chrysin (20 mg/kg body weight/day) and Propolis (100 mg/kg body weight day) were injected intraperitoneal to mice bearing 1cm3 solid tumor of Ehrlich ascites carcinoma (EAC) for 21 consecutive days. Mice were whole body exposed to 1 Gy of gamma radiation (two fractionated doses at 11 and 25 days post EAC inoculation, respectively). Treatments with Ch or P markedly suppress the proliferation of tumor in mice bearing solid Ehrlich tumor (EAC mice). The activity of interferon-gamma (IFN-γ) was significantly decreased in the treated mice compared to EAC mice. The concentrations of m-RNA for angiogenic factor (tumor necrosis factor alpha -TNF-α), free radicals as well as nitric oxide (NO) concentration were significantly decreased collimated with improvements in apoptotic regulators (Caspase-3 activity) compared to EAC mice. Moreover, the histopathological investigation confirms the improvement exerted by Ch or P even in EAC mice group or mice bearing solid Ehrlich tumor and subjected to γ-irradiation (EAC+R group). Exposure to gamma radiation sustained the modulatory effect of Ch or P on tumor when compared with EAC mice and those injected with Ch (EAC+Ch) or EAC and injected with P (EAC+P). Hence, Ch or P might represent a potential therapeutic strategy for increasing the radiation response of solid tumor.

The Effect of N-Acetylcysteine on Oxidant/Antioxidant Status in Irradiated Rats

N-Acetylcysteine (NAC) is both a strong antioxidant and a glutathione precursor. The effect of NAC on the oxidant/antioxidant status of some tissues of the irradiated rats was investigated. Twenty one rats were assigned to 3 groups; the control group, the irradiation group, for which physiological saline solution was administered as i.p. for three days and then, 9 Gy gamma irradiation was applied, and 3rd irradiation + NAC group for which NAC was adminis-tered as i.p. for three days as 300 mg/kg body weight and then the same dose of irradiation was applied. Upon irradia-tion, the increase determined in malondialdehyde (MDA) was significant in the liver, kidney, and brain tissues of the rats (P˂0.05). While glutathione peroxidase (GSH-Px) activity decreased in all of the tissues and superoxide dismutase (SOD) activity only in the liver (P˂0.01), glutathione (GSH) levels significantly increased in the kidney and ovarium tissues (P˂0.001). While NAC administration returned the increased MDA levels in the kidney and brain as a result of irradiation to normal levels (P˂0.05), it was determined that it did not return the increased MDA levels in the liver tissue to the normal level (P˂0.001). While NAC addition led to a significant increase in GSH levels of the liver, heart, spleen, brain and ovarium tissues compared to both control and irradiation groups, it caused a significant decrease in the kid-ney tissue compared to irradiation group (P˂0.001). As a result of NAC addition, a significant decrease was determined in spleen GSH-Px activity, heart and ovarium SOD activity compared to control and irradiation groups (P˂0.05). It can be asserted that GSH increasing by the addition of NAC is the main antioxidant that has a role in decreasing oxidative stress occurring as a result of irradiation. In the examination of MDA values, it was found that the addition of NAC pro-tected the kidney and brain against the oxidative damage induced by irradiation but NAC addition could remain insuffi-cient for the liver.

Mutant Selection Short-stem of M2 Generation Mentik Wangi Rice Resulted from Irradiation with Gamma-ray.

Mentik Wangi is local rice variety from Magelang, Central Java. This rice has superior properties, which is tender texture, has fragrant, but also has a long harvesting age and tall stems so that it easily collapses during heavy wind. The purpose of this study was to determine the performance of M2 mutants resulting from 150, 200 and 250 Gy gamma irradiation and to find out the plants to obtain short-stemmed, short-lived mutant plants with high productivity. The tools used in this study include tractors, hoes, rakes, sickles, stakes, code boards, gauges, rulers, raffia, scissors, analytical scales, newspapers, stationery. The materials used are M2 generation Mentik Wangi rice seeds which are the result of 250 Gy gamma-ray irradiation, control Mentik Wangi rice seeds (without radiation), urea fertilizer, Ponska, SP36, KCl, ZA and pesticides. Plant treatment includes weed control, irrigation, fertilization, pest and disease control and put nets to avoid bird attacks. The study was conducted using a simple design experiment. The results showed the difference between Mentik Wangi rice M2 generation gamma-ray irradiation with control plants. The results of the selection of short-trunked mutant plants, short-lived and have high productivity. M2 selection obtain 11 plants mutant from irradiation with 150 Gy, 22 plants mutant from irradiation with 200 Gy and 24 plant mutant from irradiation with 250 Gy that have short stems and high productivity.

In vitro response and effect of gamma irradiation on four local indica rice varieties

In vitro response of four local Indica rice cultivars viz. Sadamota, Kachamota, Moulata and Dudhkalam was evaluated. The aim of this study is to develop an efficient protocol for callus induction, plant regeneration and to observe the effect of gamma radiation on plant regeneration for creating possible genetic variability. In Different concentration of 2,4-D and growth regulators were supplemented with MS medium (Murashige and Skoog’s) to observe their callus induction frequency using mature embryo as explant. Among the cutivars, the highest primary callus (92.55%) as well as embryogenic callus induction (56.26%) was showed in sadamota at 3.0 mgl-1 2,4-D and 10 mgl-1 kinetin under dark condition. Twenty one days old embryogenic calli were exposed to 0, 2, 4 and 6 Gy of gamma rays and transferred to regeneration medium. Both callus growth and regeneration capacity were found to be decreased with increasing level of exposure to gamma rays. The doses of 4 Gy of gamma radiation were found to be the 50% inhibition dose for callus growth and plant regeneration in sadamota and kachamota, repectively whereas the 50% inhibition dose for moulata and dudhkalam at 2 Gy. This results indicate that sentivity of gamma radiation on rice callus depends on genotype of a genus.

Gamma radiation improves AD pathogenesis in APP/PS1 mouse model by potentiating insulin sensitivity

Alzheimer's disease (AD) is the largest unmet medical complication. The devastation caused by the disease can be assumed from the disease symptoms like speech impairment, loss of self-awareness, acute memory loss etc. The individuals suffering from AD completely depend on caregivers and have to bear the high cost of treatment which increases the socio-economic burden on the society. Recent studies have shown that radiation exposure can have therapeutic effects when given in suitable amount for a specific time period. Therefore, we investigated the role of gamma irradiation in AD pathogenesis. The effect of radiation on amelioration of disease progression was studied in AD transgenic mice model (APP/PS1). Our in-vivo studies using APP/PS1 mice demonstrated that a single dose of 4.0 Gy gamma irradiation improves AD associated behavioral impairment. Radiation exposure also increased the level of anti-oxidant enzymes and reduced the astrocyte activation in the brain of APP/PS1 mice. A significant reduction was observed in AD associated proteins (APP, pTau, BACE) and neurofibrillary tangle formations (NFTs). Exposure to a single dose of 4 Gy gamma radiation also increased glucose metabolic functionality in AD transgenic mouse model. The kinases involved in insulin signaling such as GSK, ERK and JNK were also found to be modulated. However, an increased level of GSK3β (ser 9) was observed, which could be responsible for downregulating ERK and JNK phosphorylation. This resulted in a decrease in neurofibrillary tangle formations and amyloid deposition. The reduced hyperphosphorylation of Tau can be attributed to the increased level of GSK3β (ser 9) downregulating ERK and JNK phosphorylation. Thus, a single dose of 4 Gy gamma irradiation was found to have therapeutic benefits in treating AD via potentiating insulin signaling in APP/PS1 transgenic mice.

Iodoquinazolinones bearing benzenesulfonamide as human carbonic anhydrase I, II, IX and XII inhibitors: Synthesis, biological evaluation and radiosensitizing activity

In the present work, we report the design and synthesis of a set of iodinated quinazolinones carrying benzenesulfonamide moiety as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The target compounds showed promising inhibitory activity against the four examined human (h) CA isoforms; I, II, IX and XII. Compounds 4-18 displayed variable inhibition constants, ranging as follows: 7.6–782.8 nM for hCA I, 34.4–412.1 nM for hCA II, 29.1–2225.3 nM for hCA IX and 8.8–429.4 nM for hCA XII. Compound 9, the most potent against the tumor-specific CA IX/CA XII (KI = 29.1 and 8.8 nM) gives the possibility to evaluate its cytotoxicity and selectivity in vitro against HepG-2, HCT-116 and MCF-7 cancer cell lines. Compound 9 showed significant cytotoxicity against the tumor cell lines (IC50 = 1.78, 1.94 and 3.07 μM, respectively) and relatively lower toxicity against WI38 normal cell line. The radiosensitizing activity of compound 9 was evaluated and displayed an increase in the radiation-induced cell death in cancer cells after receiving a single dose of 8 Gy gamma radiation. Thus, radiation was able to enhance the antiproliferative activity of compound 9. Molecular docking of 9 into the active site of CA IX and XII revealed the key interactions that could explain its potent activity and selectivity towards these isoforms.

Luminescence properties of natural dead sea salt pellet dosimetry upon thermal stimulation

In the event of a radiological accident or attack, immediate need arises for reliable estimation of dose to the population from an affected environment. This would contribute to proper medical treatment and any need for isolation of affected areas. As such, it is important to improve dosimetry assessment through use of locally available materials, the latter acting as accident/prospective dosimeters. Present investigation has examined the TL properties of natural salt collected in Jordan, from the Dead Sea, and exposed using 60Co gamma radiation. Entrance doses ranging from 2 to 10 Gy have been delivered, providing desirable luminescence features. Natural Dead Sea NaCl are produced in cylindrical pellet form, achieved with 0.1 and 0.3 cm thickness sized from the salt grains obtained by a compression force of 5.0 ± 0.1 tonnes. With these NaCl pellets, linear dose response has been achieved, producing strong TL yield for a 0.1 cm thick layer, exceeding that of 0.3 cm thickness by a factor of 3. The shape of the glow curves was found to be independent of delivered dose, the main TL dosimetric peak remaining within the range 180 °C to 280 °C and 300 °C to 400 °C for the 0.1- and 0.3 cm NaCl pellets respectively. Computerised glow curve deconvolution was carried out, comprising of ten peaks, with associated activation energies and frequency factors. TL response per unit mass of NaCl pellets for both thicknesses were found to be energy dependent, predominating in yield at 60 keV. Over a period of 35 days the 0.3 cm NaCl pellet showed the least effect of fading, with loss of TL signals of 56% compared to an 81% loss for the 0.1 cm pellet. It is also noted that the combination of low activation energy and high frequency factors for the electrons to escape a trap for the 0.1 cm NaCl pellet samples subjected to 2 Gy gamma irradiation resulted in a highly substantial loss of TL signal over the first 7 days in comparison to the 0.3 cm NaCl pellet. Both samples thicknesses were unable to produce reproducible TL responses for the second and greater use. It has also been found that in addition to particle size, moisture and pre-irradiation annealing influence the TL properties. The excellent TL properties achieved by 0.1 cm NaCl pellets indicate their potential use as an accident/prospective dosimeter.

Metformin fights against radiation-induced early developmental toxicity

Nuclear pollution intertwined accidental irradiation not only triggers acute and chronic radiation syndromes, but also endangers embryonic development in sight of uncontrollable gene mutation. Metformin (MET), a classic hypoglycemic drug, has been identified to possess multiple properties. In this study, we explored the radioprotective effects of MET on the developmental abnormalities and deformities induced by irradiation among three “star drugs”. Specifically, zebrafish (Danio rerio) embryos exposed to 5.2 Gy gamma irradiation at 4 h post fertilization (hpf) showed overt developmental toxicity, including hatching delay, hatching rate decrease, developmental indexes reduction, morphological abnormalities occurrence and motor ability decline. However, MET treatment erased the radiation-induced phenotypes. In addition, MET degraded inflammatory reaction, hinders apoptosis response, and reprograms the development-related genes expression, such as sox2, sox3, sox19a and p53, in zebrafish embryos following radiation challenge. Together, our findings provide novel insights into metformin, and underpin that metformin might be employed as a promising radioprotector for radiation-induced early developmental toxicity in pre-clinical settings.

Two distinct time dependent strategic mechanisms used by Chlorella vulgaris in response to gamma radiation

Microalgae as one of the key components of food chains in aquatic environments are promising biological models for investigating gamma irradiation effects on eukaryotic organisms. Understanding resistance mechanisms in these organisms as simple models might illuminate how gamma irradiation resistance improves in these algae and even more complex organisms. The present study aimed to investigate the effects of ionizing irradiation on Chlorella vulgaris as a stress-tolerant microalga and to find how the eukaryotic cells would tolerate such stressful conditions. The physiological responses and biochemical alterations of C. vulgaris were analyzed at three different time points (0, 16, and 48 h) after 600 Gy gamma irradiation. Compared to the control, gamma-irradiated algae had slower growth rate with significantly longer lag phase, less chlorophyll and protein contents at time 0, which were compensated and recovered during the next 48 h. The results also showed spontaneous H2O2 burst accompanied by a higher rate of lipid peroxidation and electrolyte leakage, a rapid increase of catalase activity and more ferric reducing antioxidant power immediately after irradiation. During a 48-h period, most alterations stabilized. Raising trends were observed in the carotenoid contents, the ratios of carbohydrates, amide I and amide II to fatty acids. Principal component analysis and hierarchical clustering suggest two possible distinct mechanisms: a “quick” one including spontaneous responses by boosting H2O2, amplifying enzymatic antioxidant systems, and increasing compatible solutes like proline and a “delayed” responsive strategy including the increase of soluble carbohydrates, carotenoids, and stress-related proteins triggered several hours after irradiation.

Mutation of Arthrospira platensis by gamma irradiation to promote phenol tolerance and CO2 fixation for coal-chemical flue gas reduction

In order to promote phenol tolerance and the carbon fixation rate of cells during CO2 sequestration in coal chemical flue gas, γ-ray irradiation from cobalt-60 (60Co) was used to mutate Arthrospira platensis to generate efficient strains. A phenol-tolerant strain Mutant 11k was obtained with 11,000 Gy of gamma irradiation. The phenol degradation efficiency of the mutant was 34.7 % higher than that of wild strain, attributing to the increased activity of phenol hydroxylase that catalyzed phenol to generate catechol. The catechol 1,2-dioxygenase activity in mutant cells was enhanced by 39.5 % while catechol 2,3-dioxygenase was weakened by 23.8 %, revealing that the β-ketoadipate pathway plays a more important role than 2-hydroxymuconic semialdehyde pathway in phenol degradation. The activity of superoxide dismutase and catalase increased by 6.1 % and 39.8 %, respectively, reducing peroxide damage and maintaining rapid cell growth. The contents of chlorophyll-a and maximum quantum yield of photosystem II in mutant cells were higher than those in wild strain. The biomass yield and carbon fixation rate of mutant were 20.8 % and 22.4 % higher, respectively, than those of the wild strain.

Combined action of Lavandula angustifolia Miller essential oil and gamma irradiation treatment on some biological aspects of the Mediterranean flour moth Ephestia kuehniella (Zeller)

This study evaluated the effectiveness of an integrated pest management intervention for controlling the Mediterranean flour moth Ephestia kuehniella Zeller using gamma radiation and Lavandula angustifolia Moench essential oil as feasible alternatives to synthetic insecticides. The mortality rate of E. kuehniella larvae treated with either gamma radiation or L. angustifolia essential oil separately was much lower than the mortality rate after the combined treatment. High synergistic effects (Synergism = 0.1) were observed in all dosages, especially using 1.14 and 1.7 µL/L air of L. angustifolia in combination with 200 Gy of gamma radiation, which was more effective than the other treatments. The results of the antifeedant test indicated that the relative growth rate and relative consumption rate in fumigated (0.021 and 0.021 mg/mg/day) and irradiated (0.026 and 0.049 mg/mg/day) larvae were significantly lower than those of non-treated ones (0.035 and 0.093 mg/mg/day). The results also showed a significant increase in the efficacy of conversion of ingested food and feeding deterrent index due to both irradiation and essential oil. The experiments showed that the known insecticidal effectiveness of essential oils can be enhanced by preliminary irradiation.