Effects of radiation and role of plants in radioprotection: A critical review

Enhancing Radiotherapy Tolerance With Papaya Seed-Derived Nanoemulsions

Flavonoid-rich plant materials have gained attention for their potential to reduce radiotherapy side effects. Carica papaya (CP) seeds, known for high flavonoid content, hold promise for therapeutic applications. This study explored the extraction and evaluation of two oils-sunflower oil-based papaya oil (SPO) and pure papaya oil (PPO)-and their nano emulsions (SPOE and PPOE), derived from CP seeds, for radioprotective effects. Chemical analysis using QTOF-MS revealed antioxidants and phytochemicals in the oils and emulsions. Size analysis and zeta potential measurements using dynamic light scattering (DLS) showed particle sizes of 140 ± 26.06 nm for PPOE and 293.7 ± 49.42 nm for SPOE. Post-radiation, both SPOE and PPOE significantly enhanced cell viability, with values of 72.24 ± 3.92 (p ≤ 0.001) and 75.85 ± 2.62 (p ≤ 0.001), respectively. These nanoemulsions show potential as topical agents for reducing radiation-induced tissue damage in radiotherapy. Despite the promising in vitro findings, further in vivo studies are needed to confirm the clinical relevance of these nanoemulsions. Additionally, their incorporation into sunscreen formulations could provide further protection against radiation-induced skin damage, broadening their potential applications.

Uranium's hazardous effects on humans and recent developments in treatment

Uranium, a naturally occurring element, is predominantly recognized for its role as fuel in both civilian and military energy sectors. Concerns have been raised regarding the adverse environmental impacts and health risks associated with uranium mining due to the exposure it causes. Such exposure leads to systemic toxicity, affecting pulmonary, hepatic, renal, reproductive, neurological, and bone health. This review identifies significant research gaps regarding detoxification methods for uranium contamination and recommends further advancements, including genetic modification and exploration of plant compounds. A comprehensive review of published research materials from diverse sources of uranium, including various treatments and hazardous impacts on the human body, was conducted. Additionally, a PRISMA analysis was performed in this study. This review emphasizes the importance of collaboration and the formulation of research-informed regulations to effectively safeguard vulnerable communities from the consequences of contamination. Public discourse often emphasizes the significance of radiotoxicity; however, the non-radioactive chemotoxicity of uranium has been identified as a significant risk factor for environmental exposures, contingent upon species, enrichment, and exposure route. Given these serious health consequences, several methods are being investigated to ameliorate uranium toxicity. In response to these concerns, several techniques, such as phytomedicinal treatments, biochemical approaches, and chelation therapy, have been investigated to minimize the adverse effects of uranium exposure in the human body.

Opuntia ficus indica cladode extract inhibit DNA double-strand breaks and locally multiply damaged sites induced by gamma radiation

It is beyond doubt that radiotherapy is extremely effective in treating a wide variety of cancers. The sensitivity of the surrounding normal tissues limits the amount of radiation administered to the tumor. There is an urgent need to develop a treatment that combines pharmacological treatment with ionizing radiation (IR) specifically designed to specifically target cancer cells while protecting the surrounding normal tissue, resulting in an increase in the efficacy of the cancer treatment. IR could cause many types of DNA lesions. Double-strand breaks (DSBs) andlocally multiple damaged sites (LMDS)arethe main radiotoxic damages.Recently, the identification of new antioxidants from natural sources has attracted the attention of scientists. In this context, the present study aims to determine if the Opuntia ficus indica cladode extract (CE) can be used as a radioprotector.

MATERIALS AND METHODS

The DNA treated by 137Cs γ-radiation (25-700 Gy) in the absence or presence of cactus cladode extract (CCE) was added to theE. colibase excision repair. The amounts of both DNA damages were calculated using the electrophoretic method.

RESULTS

The irradiation of DNA in the presence of CCE induced a dramatic decrease of the yields of purine and pyrimidine-DSB. A decrease of65 % and 84 % of the purine and pyrimidine-DSB sensitive sites have been calculated, respectively, when the sample added CCE3 during the radiotreatment. Moreover, a reduction of 80 % in the amount of Nth + Fpg-DSB SSs (non-DSB cluster damage) after γ-irradiation in the presence of CCE3 was observed.

CONCLUSION

Through the present it was found that the CCE can play an important role as a radio protector, maybe by scavenging the ROS formed during radio treatment or by other unknown pathways. The most toxic DNA lesions (DSBs, and LMDS) decreased dramatically. Studies aimed at obtaining more documentation about CCE components with potential radio-preventive activity are desirable because of their protective properties.

Polysaccharide from Helianthus tuberosus L. as a potential radioprotector

INTRODUCTION

Radioprotectors help to protect the body or at least minimize the negative consequences of radiation exposure. The present study aimed to assess the radioprotective potential of Helianthus tuberosus L. polysaccharide (HTLP) in vitality and micronuclei tests. To assess the cytotoxic effects of HTLP, both vitality and MTT reductase assays were conducted.

MATERIALS AND METHODS

RAW 264.7 cells viability was assessed 24 h after adding 200 μg/ml HTLP solution by staining cell cultures with propidium iodide and bis-benzimide to detect the nuclei of dead cells and the total number of cells in culture. To assess cell viability via cellular metabolic activity MTT test was used. In this work outbred 24-30 g 5-months old SHK mice have been used. Irradiation was provided with proton beams with an energy of 660 MeV at a dose rate of 80 Gy with doses 1.5 Gy for micronuclei test and 8.5 Gy for survival test. Whole body X-ray irradiation was conducted using the RUT-15 therapeutic X-ray unit with doses of 1.5 Gy for MN test and 6.5 Gy for survival. The HTLP sterile solution in dose 100 μg/animal was injected into the tail vein 15 min before X-ray or proton irradiation.

RESULTS AND CONCLUSION

s: Vitality test showed no significant differences between the control group and cells treated with 200 μl of 200 μg/ml HTLP solution, though a greater variability was noted. In contrast, the MTT assay indicated enhanced cell viability in the HTLP-treated cells. HTLP does not exert any toxic effects in cell culture. Moreover, results of MTT reductase assay shows, that HTLP may enhance the cells' metabolic activity. Animals pre-treated with HTLP displayed a significant reduction in micronuclei formation, showing five times fewer micronuclei in bone marrow cells compared to the non-treated group. This comparison highlights HTLP's potential protective effect against radiation-induced chromosomal damage. HTLP treatment demonstrates a significant reduction in hazard compared to the control, indicating its protective effects against irradiation. Thus, it can be concluded that the use of HTLP increases the likelihood of animal survival under the ionizing effects of X-rays and protons. The survival analysis reveals that the HTLP-treated groups exhibit a higher survival rate compared to both the control and Cysteamine-treated groups, suggesting a significant protective effect of HTLP against irradiation, regardless of the type of irradiation (proton or X-ray) with p < 0.0001.

Plant acclimation to ionising radiation requires activation of a detoxification pathway against carbonyl-containing lipid oxidation products

Ionising γ radiation produces reactive oxygen species by water radiolysis, providing an interesting model approach for studying oxidative stress in plants. Three-week old plants of Arabidopsis thaliana were exposed to a low dose rate (25 mGy h-1) of γ radiation for up to 21 days. This treatment had no effect on plant growth and morphology, but it induced chronic oxidation of lipids which was associated with an accumulation of reactive carbonyl species (RCS). However, contrary to lipid peroxidation, lipid RCS accumulation was transient only, being maximal after 1 day of irradiation and decreasing back to the initial level during the subsequent days of continuous irradiation. This indicates the induction of a carbonyl-metabolising process during chronic ionising radiation. Accordingly, the γ-radiation treatment induced the expression of xenobiotic detoxification-related genes (AER, SDR1, SDR3, ALDH4, and ANAC102). The transcriptomic response of some of those genes (AER, SDR1, and ANAC102) was deregulated in the tga256 mutant affected in three TGAII transcription factors, leading to enhanced and/or prolonged accumulation of RCS and to a marked inhibition of plant growth during irradiation compared to the wild type. These results show that Arabidopsis is able to acclimate to chronic oxidative stress and that this phenomenon requires activation of a carbonyl detoxification mechanism controlled by TGAII. This acclimation did not occur when plants were exposed to an acute γ radiation stress (100 Gy) which led to persistent accumulation of RCS and marked inhibition of plant growth. This study shows the role of secondary products of lipid peroxidation in the detrimental effects of reactive oxygen species.

Neuroprotective Action of Selected Natural Drugs Against Neurological Diseases and Mental Disorders: Potential Use Against Radiation Damage

Exposure to radiation, ionizing and non-ionizing radiation, is a significant concern in modern society. The brain is the organ that is most sensitive to radiation exposure. This review describes how exposure to radiation can affect neurotransmitters in different brain regions, affecting brain function. This review covers neurodegenerative diseases such as Alzheimer's, Parkinson's, and neuroinflammation due to changes in neurons in the central nervous system, and the effects thereon of medicinal plants such as Allium cepa, Allium sativum, Centella asiatica, Coriandrum sativum, and Crocus sativus plants, used for centuries in traditional medicine. These herbal medicines exert free radical scavenging, and antioxidant as well as anti-inflammatory properties which can be beneficial in managing neurological diseases. The present review compiles the neuroprotective effects of selected natural plants against neurological damage, as well as highlights the different mechanisms of action elicited to induce and produce beneficial effects. The current review describes recent studies on the pharmacological effects of neuroprotective herbs on various neurological and mental illnesses, and shows the way further studies can impact this field, including potential effects on radiation-induced damage.

Evaluation of the protective properties and genotoxic potential of pyrazolo pyridine derivatives against neutron and gamma radiation using the Ames/Salmonella test system

PURPOSE

Nuclear applications are being increasingly used in various fields, necessitating studies to protect from radiation hazards and their effects. In this study, five different chemical structures of pyrazolo [3,4-b] pyridine derivatives were synthesized. The gamma and neutron radiation protective abilities of these samples were determined and demonstrated their potential use as ingredients in radioprotective drugs.

MATERIAL AND METHODS

Gamma radiation absorption parameters were calculated both theoretical and experimental. Important attenuation parameters for fast neutrons (4.5 MeV energy radiation) were figured out using the Monte Carlo simulation Geant4 code. Additionally, experimental dose rates were measured for each sample and compared to those of Paraffin and high-density polyethylene, an organic substance. Besides, Ames/Salmonella test system was aimed to detecting genotoxicity features of pyrazolo pyridine derivatives.

RESULTS

All results demonstrated that each sample possesses both gamma and neutron radiation attenuation capabilities. It was determined that sample PPC4 (C20H14BrN5) exhibited the highest gamma radiation attenuation capacity among all samples, while sample PPC2 (C22H20N6) displayed an excellent neutron stopping capacity. The genotoxic properties of pyrazolo[3,4-b] pyridine derivatives were examined using the Ames/Salmonella test, and as a result, it was determined that these substances did not exhibit genotoxic effects at test doses up to 5 mM.

CONCLUSION

All obtained results indicate that all PPC (pyrazolo[3,4-b] pyridine derivatives) samples do not possess a toxic effect, and they can be utilized as an active substance for the development of a drug or cream with protective properties against both gamma and neutron radiations.

Biyang floral mushroom-derived exosome-like nanovesicles: characterization, absorption stability and ionizing radiation protection

Diet-derived exosome-like nanovesicles are a class of natural active substances that have similar structures and functions to mammalian exosomes. Biyang floral mushrooms and their active extracts have been found to possess radioprotective effects and to deeply explore their novel active substances, the radioprotective effects of Biyang floral mushroom-derived exosome-like nanovesicles (BFMELNs) were investigated in this study. Results showed that these surface-negatively charged vesicles possessed an ideal size and good stability against environmental changes such as temperature and gastrointestinal digestion. Furthermore, BFMELNs could effectively be taken up by HL-7702 cells and Caco-2 cells through cellular phagocytosis mediated by clathrin and dynein. Emphatically, BFMELNs with an exosome-like morphology contained RNA, proteins, lipids, polyphenols and flavonoids to exert good antioxidant and radioprotective effects in vitro. Meanwhile, BFMELNs also exhibited good radioprotective effects by restoring peripheral blood indexes, mitigating damage to organs, and regulating the redox state in mice. Collectively, BFMELNs showed promise as novel and natural radioprotective nano-agents for preventing IR-induced oxidative stress damage.

Natural Guardians: Natural Compounds as Radioprotectors in Cancer Therapy

Cancer remains a significant global health challenge, with millions of deaths attributed to it annually. Radiotherapy, a cornerstone in cancer treatment, aims to destroy cancer cells while minimizing harm to healthy tissues. However, the harmful effects of irradiation on normal cells present a formidable obstacle. To mitigate these effects, researchers have explored using radioprotectors and mitigators, including natural compounds derived from secondary plant metabolites. This review outlines the diverse classes of natural compounds, elucidating their roles as protectants of healthy cells. Furthermore, the review highlights the potential of these compounds as radioprotective agents capable of enhancing the body's resilience to radiation therapy. By integrating natural radioprotectors into cancer treatment regimens, clinicians may improve therapeutic outcomes while minimizing the adverse effects on healthy tissues. Ongoing research in this area holds promise for developing complementary strategies to optimize radiotherapy efficacy and enhance patient quality of life.

Exploring low-dose gamma radiation effects on monoterpene biosynthesis in Thymus vulgaris: insights into plant defense mechanisms

Thymus vulgaris, commonly known as thyme, is a plant renowned for producing monoterpenes. This study aimed to understand the effects of low-dose gamma radiation, specifically in the range of 1-5 Gy, on various traits of Thymus vulgaris, providing context on its importance in agricultural and medicinal applications. The research explored morpho-physiological, biochemical, and gene-expression responses in thyme plants under no gamma- and gamma-ray exposure conditions. The study revealed complex relationships between gamma-ray doses and plant characteristics. In particular, shoot and root lengths initially increased with low doses (1-3 Gy) but decreased at higher doses (5 Gy), suggesting a dose-dependent threshold effect. Similarly, shoot and root fresh weights displayed an initial increase followed by a decline with increasing doses. Biochemical parameters showed dose-dependent responses, with low to moderate doses (1-3 Gy) stimulating enzyme activities and high doses (5 Gy) inhibiting them. Gene expression analysis was focused on the following specific genes: thymol synthase, γ-terpinene synthase, and carvacrol synthase. Low to moderate doses increased the expression of these genes, resulting in increased production of bioactive compounds. However, higher doses had diminished effects or suppressed gene expression. Metabolite analysis demonstrated dose-dependent responses, with moderate doses enhancing secondary metabolite production, while higher doses provided limited benefits. These findings underscore the implications of using gamma radiation to enhance secondary metabolite production in plants and its potential applications in agriculture, medicine, and environmental science. The study emphasizes the potential of gamma radiation as an external stressor to influence plant responses and highlights the importance of understanding such effects in various fields.

Radioprotective effect of nanoniosome loaded by Mentha Pulegium essential oil on human peripheral blood mononuclear cells exposed to ionizing radiation

OBJECTIVE

The present study aimed to assess the radioprotective effect of nanoniosomes loaded by Mentha Pulegium essential oil (MPEO-N nanoparticles) as a natural antioxidant on human peripheral blood mononuclear cells (PBMCs).

SIGNIFICANCE

Despite the applications and advantages of ionizing radiation, there are many radiation risks to biological systems that are necessary to be reduced as much as possible.

METHODS

MPEO-N nanoparticles were prepared by the lipid thin film hydration method, and its physicochemical characteristics were analyzed. PBMCs were then irradiated with X-ray using a 6 MV linear accelerator at two radiation doses in the presence of nontoxic concentrations of MPEO-N nanoparticles (IC10). After 48 and 72 h of incubation, the radioprotective effect was investigated by measuring survival, apoptosis, and necrosis of PBMCs, using MTT assay and flow cytometry analysis.

KEY FINDINGS

The hydrodynamic diameter and zeta potential of nanoniosomes were 106.0 ± 4.69 nm and -15.2 ± 0.9 mV, respectively. The mean survival percentage of PBMCs showed a significant increase only at a radiation dose of 200 cGy compared with the control group. The percentages of apoptosis and necrosis of cells in the presence of MPEO-N nanoparticles at both radiation doses and incubation periods (48 and 72 h) demonstrated a significant reduction compared with the control.

CONCLUSION

MPEO-N nanoparticles as a natural antioxidant, exhibited a favorable radioprotective effect by a significant reduction in the percentage of apoptosis and necrosis of irradiated PBMCs.

Optimization of radioprotective dose of Juglans nigra leaf extract using response surface methodology

J. nigra leaf contains mixture of various pharmacologically active compounds and it is assumed that they may have the potential radioprotective effect. The purpose of this work was to predict radioprotective doses by correlating changes in organ distribution of radiopharmaceuticals with extract dose levels and rat body weight using response surface methodology (RSM) based on a second-order polynomial equation. The extract was administered daily by oral gavage to rats at dose of 6.9, 10.3, or 13.7 mg kg-1 body weight (bw) day-1 for 10 days. On the eleventh day, 0.1 ml of the one radiopharmaceutical (Na99mTcO4, 99mTc-dimercaptosuccinic acid and 99mTc-tin colloid) was injected into the tail vein. The statistical parameters: the coefficient of determination (0.81-0.95), the coefficient of variation (3.05-11.1), the adequate precision (8.82-19.12) and the mean relative percentage deviation (± 2.3-8.2) were indicated the precision and reliability of RSM. Using RSM, the predicted daily dose of leaf extract ranging from 11.19 to 11.99 mg kg-1 bw may be considered as an optimal daily radiopotective dose for protection of organs from radiation in cases of planned radiation exposures.

Fucoxanthin Abrogates Ionizing Radiation-Induced Inflammatory Responses by Modulating Sirtuin 1 in Macrophages

Ionizing radiation (IR) triggers an overproduction of reactive oxygen species (ROS), disrupting the normal function of both immune and metabolic systems, leading to inflammation and metabolic disturbances. To address the pressing requirement for protection against IR, fucoxanthin (FX), a naturally occurring compound extracted from algae, was utilized as an efficient radioprotective agent in macrophages. In this study, we cultured murine RAW 264.7 macrophages and treated them with FX, along with agents influencing the activity of sirtuin 1 (SIRT1) and estrogen receptor α (ERα), to investigate their impact on IR-induced cellular responses. FX significantly attenuated IR-induced upregulation of pro-inflammatory genes (Il1b, Tnf, and Ccl2) and inhibited macrophage polarization toward the pro-inflammatory M1 phenotype. Additionally, FX regulated IR-induced metabolic genes mediating glycolysis and mitochondrial biogenesis. The ability of FX to mitigate IR-induced inflammation and glycolysis was ascribed to the expression and activity of SIRT1 and ERα in macrophages. This study not only uncovers the underlying mechanisms of FX's radioprotective properties but also highlights its potential as a protective agent against the detrimental effects of IR, thus offering new opportunities for enhancing radiation protection in the future.

A Narrative Review of the Herbal Preparation of Ayurvedic, Traditional Chinese, and Kampō Medicines Applied as Radioprotectors

In recent years, there has been growing scientific interest in the search for natural radioprotectors that can be used to mitigate the effects of radiation on patients, healthcare personnel, and even for space travel. This narrative review covers the past fifty years and focuses on herbal preparations of Ayurvedic, Traditional Chinese, and Kampō Medicines that have the potential to reduce or eliminate the harmful effects of radiation. Our findings highlight ten herbal preparations, namely Abana, Amalakyadi Churna, Amritaprasham, Brahma, Bu-zhong-yi-qi-tang (BZYQT), Chyavanaprasha, Cystone, Geriforte, Mentat, and Triphala, which have demonstrated potential radioprotective effects. This review examines their composition, properties, and possible mechanisms of action in relation to their radioprotective properties. Exploring the ethnobotany of traditional Asian medicine is particularly interesting as it may lead to the discovery of new active compounds with radioprotective properties.

Evaluation of morpho-physiological responses and genotoxicity in Eruca sativa (Mill.) grown in hydroponics from seeds exposed to X-rays

Due to its potential applications in cultivated plants, ionizing radiation (IR) and its effect on organisms is increasingly studied. Here we measured the effects of ionizing radiation on Eruca sativa by analyzing plants from irradiated seeds (1 and 10 Gy) grown in hydroponics. We measured several morpho-physiological traits and genotoxicity. Radiation stress induced a noticeable variability of the morpho-physiological traits highlighting decreased plant vigor. Shoot length and leaf number were significantly higher in 1 Gy-treated samples, whereas root length was significantly higher in 10 Gy treated plants. Stomata number significantly increased with IR dose, whereas both pigment and Rubisco content decreased under radiation stress. Phenol content significantly increased in 1 Gy treated samples, otherwise from total antioxidants, which were not different from control. Most results could find a feasible explanation in a hormesis-like pattern and in a decreased plant vigor under radiation stress. IR induced genotoxic damage, evaluated by ISSR markers, in 15 day old leaves; specifically, a severe decrease in the genome template stability was observed. However, a partial recovery occurred after 2 weeks, especially under the lowest dose (i.e., 1 Gy), suggesting that DNA damage detection and repair mechanisms are active. Pigment content and genotoxic damage may serve as proxies for evaluating plant responses to IR stress, since they show univocal dose-dependent trends. The use of more checkpoints for analyses and more doses over a wider range, as well as the focus on different metabolites, could help elucidate plant response in terms of morpho-physiological changes.

Aqueous Extract of Emblica officinalis Linn (Indian gooseberry) in Combination with Iodine is More Efficacious than Iodine Alone in Mitigating Mucositis in Head and Neck Cancer Patients Undergoing Curative Radiotherapy: Retrospective Observations

Mucositis is a very painful unavoidable and common side effect in head and neck cancer patients undergoing curative radiotherapy and can affect the planned treatment. In this study, attempt is made at understanding the efficacy of Emblica officinalis Linn (amla) when combined with providone iodine in mitigating radiation-induced mucositis, weight loss and tumor control. This was a retrospective chart based study and was carried out by extracting the data from the files of patients with cancer of head and neck who used amla in combination with iodine or iodine alone during the course of the curative radiotherapy (> 60 Gy). The data was entered in to Microsoft excel and subjected to statistical analysis using SPSS 17 software. The results indicate that when compared with iodine alone, the group where iodine and amla gargling were used was very effective in delaying mucositis, reduced incidence of intolerable mucositis (P = 0.027), quantitative grade of weight loss (P = 0.016), incidence of severe weight loss (P = 0.03) without affecting tumor response. The results suggest that when compared with iodine alone, amla when combined with iodine was more effective in mitigating radiation mucositis and by not interfering with the tumor cell kill. As far as the authors are aware of this is the first study that shows the usefulness of combining iodine with Amla in mitigating radiation-induced mucositis.

A Comparison of the Mediterranean Diet and Current Food Patterns in Italy: A Life Cycle Thinking Approach for a Sustainable Consumption

The transition toward more sustainable food systems, which already represents a central element of the European Farm to Fork and Green Deal strategies, could be an effective measure to contribute to global decarbonization and greenhouse gas (GHGs) reduction goals; concurrently, it could improve the health status and nutrition of the global population. In this context, the Mediterranean diet (MD) could play a considerable role, as it is generally recognized as a more balanced, healthy, and sustainable eating pattern than Western consumption patterns, which are characterized by excess food and high energy content, thus causing undesirable effects on both human health and the environment. Although traditionally linked to MD, Italy sees relatively moderate adherence by its citizens, as they consume about +75% of the daily caloric intake recommended by MD. Therefore, this study aims to quantitatively assess the potential environmental, economic, and health impacts of this lower adherence to MD by Italians. Current Italian Food Patterns (CIFP) in 2019 were analyzed and compared to the MD recommended amounts through a Life Cycle Thinking (LCT) approach (LCA) and carbon footprint (CF) analysis. The results show that CIFP, compared to MD, has +133% greater impacts on the environmental macro-area, +100% greater impacts on the human health macro-area, and +59% greater impacts on the economic macro-area (with annual fossil and mineral resource savings of $53.35 per person, $3.2 billion per year). The analysis also shows that CIFP has a CF of 6.54 × 101 kg CO2 eq, +142% over MD (2.7 × 101 kg CO2 eq), resulting in a lower environmental impact of the Mediterranean diet.

Radiosensitivity of seedling traits to varying gamma doses, optimum dose determination and variation in determined doses due to different time of sowings after irradiation and methods of irradiation in faba bean genotypes

PURPOSE

Three experiments were conducted to assess the effect of different doses of gamma radiation on various seedling traits; determine the optimum doses of gamma radiation for different faba bean genotypes; find out the variation in optimum doses with respect to the different times of sowings after irradiation and methods of irradiation.

MATERIALS AND METHODS

Five faba bean genotypes viz., L-2013-060, L-2013-092, Anandnagar Local, Gazipur Local and Bangla Gangachar were used in these experiments. In Experiment I, seeds of five experimental genotypes were exposed to different doses (100 Gy 200 Gy, 300 Gy, 400 Gy, 500 Gy, 600 Gy, 700 Gy and 800 Gy) of gamma radiation and were sown immediately after irradiation. In Experiment II, seeds of Bangla Gangachar and L-2013-060 were exposed to varying doses (100-800 Gy) of gamma radiation and were sown at seven sowings starting from 0 h to 24 h at 4-h intervals after irradiation. In Experiment III, L-2013-092 genotypes was exposed to different doses (100 -800 Gy) of gamma radiation with two different methods of irradiation.

RESULTS

In Experiment I, the lethal dose 50 (LD₅₀) values have arrived at 140 Gy, 669 Gy, 575 Gy, 386 Gy and 158 Gy for L-2013-060, L-2013-092, Anandnagar Local, Gazipur Local and Bangla Gangachar, respectively. The growth reduction 50 (GR₅₀) doses for different seedling traits ranged from 130 Gy to 320 Gy for L-2013-060, 250 Gy to 480 Gy for L-2013-092, 130 Gy to 370 Gy for Anandnagar Local, 200 Gy to 350 Gy for Gazipur Local and 250 Gy to 400 Gy for Bangla Gangachar. In Experiment II, the values for LD₅₀ of the genotypes Bangla Gangachar and L-2013-060 were significantly singular for different time intervals of sowing. The values of GR₅₀ for most of the seedling traits were found to increase with the delay in sowing after irradiation from 4 to 24 h when compared with the immediately sown seed lots. In Experiment III, LD₅₀ for L-2013-092 was 337 Gy with Method 1 and 669 Gy with Method 2. In Method 1, most of the growth parameters attained GR₅₀ doses lower than Method 2. The first method was found to increase the radiosensitivity of L-2013-092.

CONCLUSION

Every experimental genotype used in these three experiments showed dose-dependent retardation of different seedling traits. These optimized doses may be employed to establish mutant populations for exploiting the novel traits of faba bean. The time of sowing after irradiation and method of irradiation was found to be essential for confirming optimum doses.

Recent Advances in Hydrogel-Based Sensors Responding to Ionizing Radiation

Ionizing radiation and its applications are widely spread throughout life. Similar to many other things, both the positive and negative aspects of ionizing radiation should always be kept in mind. For example, a proper radiation dose can be delivered to tumor tissue to kill malignant cells in radiotherapy. On the other hand, exceeding this dose can damage the normal tissues of a human organism. Therefore, the application of sensors for measuring ionizing radiation doses is of utmost importance in many fields, especially in cancer therapy. Traditional dosimeters, such as ionization chambers, silicon diodes and thermoluminescence dosimeters, are widely used. However, they have limitations in certain aspects. Hydrogel-based sensors (or dosimeters) for measuring ionizing radiation doses attract extensive attention for decades due to their equivalence to living tissue and biocompatibility. In this review, we catalog hydrogel-based dosimeters such as polymer, Fricke, radio-chromic, radio-fluorescence and NPs-embedded dosimeters. Most of them demonstrate desirable linear response and sensitivity regardless of energy and dose rate of ionizing radiation. We aim to review these dosimeters and their potential applications in radiotherapy as well as to stimulate a joint work of the experts from different fields such as materials science, chemistry, cancer therapy, radiobiology and nuclear science.

Plant based radioprotectors as an adjunct to radiotherapy: advantages and limitations

Radioprotectors are agents that have the potential to act against radiation damage to cells. These are equally invaluable in radiation protection, both in intentional and unintentional radiation exposure. It is however, complex to use a universal radioprotector that could be beneficial in diverse contexts such as in radiotherapy, nuclear accidents, and space travel, as each of these circumstances have unique requirements. In a clinical setting such as in radiotherapy, a radioprotector is used to increase the efficacy of cancer treatment. The protective agent must act against radiation damage selectively in normal healthy cells while enhancing the radiation damage imparted on cancer cells. In the context of radiotherapy, plant-based compounds offer a more reliable solution over synthetic ones as the former are less expensive, less toxic, possess synergistic phytochemical activity, and are environmentally friendly. Phytochemicals with both radioprotective and anticancer properties may enhance the treatment efficacy by two-fold. Hence, plant based radioprotective agents offer a promising field to progress forward, and to expand the boundaries of radiation protection. This review is an account on radioprotective properties of phytochemicals and complications encountered in the development of the ideal radioprotector to be used as an adjunct in radiotherapy.

Differential Activity of Antioxidants in Testicular Tissues Following Administration of Chlorophytum borivilianum in Gamma-Irradiated Swiss Albino Mice

Background: Oxidative stress induced by radiation causes variable expression of antioxidant enzymes in a tissue-specific manner. Testicular tissues carry out the complex process of spermatogenesis, and studies indicate that testicular damages due to irradiation require long-term recovery before complete resumption. Ionizing radiation also causes oxidative stress in tissues, leading to testicular damage. Aims and Objectives: This study measured differential expression of antioxidant enzymes following administration of C. borivilianum root extract (CRB) in response to irradiation-induced oxidative stress. The activity of various important endogenous enzymatic defense systems was evaluated and correlated for strength of association. Materials and method: Two forms of C. borivilianum (CB) extracts [CB alone and CB-silver nanoparticles (AgNPs)] were administered at a dose of 50 mg/kg body weight to Swiss albino male mice for 7 consecutive days. After that, they were irradiated with 6 Gy irradiation and further used to study various parameters of antioxidant enzymes. Results: Results indicate a significant increase in the level of glutathione (GSH) and the activity of GSH-related antioxidant enzymes in irradiated mice treated with CRE and CRE-AgNPs (silver nanoparticles biosynthesized using C. borivilianum root extract) in comparison to non-pretreated ones (groups I and II). Reciprocal elevation was observed in related enzymes, that is, glutathione S-transferase activity (GST), glutathione reductase (GR), and glutathione peroxidase activity (GPx). Elevation in the activity of catalase (CAT) and superoxide dismutase (SOD) was also evident in both the irradiated groups pretreated with CRE-AgNPs. However, expression of CAT in the CRE-treated irradiated group was similar to that of the non-treated irradiated group. Higher association among CAT-SOD, CAT-GPx, and GR-GST was observed. Conclusion: Overall, it was observed that testicular cells post-irradiation in all groups go through intense oxidative stress; however, groups pretreated with CRE or CRE-AgNPs indicated better toleration and resumption of antioxidant capacity. CRE or CRE-AgNPs pretreated non-irradiated groups mostly remained within the control range indicating stimulated expression of antioxidants.

Natural radioprotectors on current and future perspectives: A mini-review

Radiation therapy is used as the primary treatment for cancer. Eighty percent of cancer patients require radiation therapy during treatment or for medical purposes. During treatment, radiation causes various biological defects in the cells. The prevalence of cytotoxicity limits the dose used for effective treatment. This method is designed to strike a balance between removing cancer cells and protecting normal tissues. Unfortunately, effective radiation is unavailable once acute toxicity occurs during clinical radiation therapy. Therefore, a lot of research interest is needed in the discovery of radioprotective drugs to accelerate treatment to reduce this toxicity (i.e., normal tissue toxicity to cancer cell death). Radiation protectors may be chemicals or drugs that minimize the damage caused due to radiation therapy in living organisms. The determination of effective and nontoxic radiation protection is an essential goal for radiation oncologists and basic radiobiologists. However, despite the advantages, many radioprotectors were found to have disadvantages which include cost, less duration, toxicity, and effect on the central nervous system. Therefore in recent years, the focus has been diverted to finding out optimal natural products to act as radioprotectors. Natural radiation protectors are plant compounds that protect normal (noncancerous) cells from damage from radiation therapy. Natural herbal products are nontoxic with proven therapeutic benefits and have long been used to treat various diseases. In conclusion, we find that there are various radiation protectors with different purposes and mechanisms of action.

Pterocarpus santalinus L. extract mitigates gamma radiation-inflicted derangements in BALB/c mice by Nrf2 upregulation

Plant-based natural extracts contain several nutrients and bioactive compounds, such as phenolics and flavonoids, that possess various health-promoting activities. This study investigated the effects of polyphenols from Pterocarpus santalinus hydroalcoholic extract (PSHE) against gamma radiation-induced derangements via the upregulation of Nrf2. Ultra High Performance Liquid Chromatography Coupled to High Resolution Mass Spectrometry (UHPLC-HRMS/MS) analysis was performed to identify the possible radioprotectors. In vivo and in vitro studies, namely Real-Time-PCR (RT-PCR) analysis, Reactive Oxygen Species (ROS) scavenging activity, lipid peroxidation and GSH levels, DNA damage and cell death studies, anti-inflammatory (Sandwich ELISA), immunomodulatory studies (antibody staining), and model free radical scavenging assays, were performed. Vanillic acid, protocatechuic acid, para-hydroxybenzoic acid, chlorogenic acid, TNF-α inhibitor (Eudesmin), isoflavone (Daidzein 7-o-glucoside), astragalin (Kaempferol 3-o-glycoside), and other polyphenols were identified in PSHE using UHPLC-HRMS/MS analysis. Prophylactic administration of PSHE (-1 h) rendered more than 33% survival in mice exposed to 8 Gy whole-body-irradiation with increased mice survival and recovery of bone marrow and spleen cellularity. Real-time RT-PCR analysis showed that PSHE treatment (50 µg/mL) upregulated Nrf2, HO-1, and GPX-1 in mice splenocytes. At 50 µg/mL, PSHE reduced ROSscavenging activity, mitochondrial and spleen membrane lipid peroxidation levels, DNA damage, and cell death, and increased GSH levels. At 10 µg/mL, PSHE treatment diminished the content of IL-6 and TNF-α. At 50 µg/mL, PSHE suppressed lymphocyte proliferation. These findings indicate that polyphenols of PSHE possess marked antioxidant, anti-inflammatory, and immunomodulatory capacities, which play important roles in the prevention of radiation damage.