Low-dose Gamma Research Articles

Combined Effect of Gamma Irradiation and Low Temperature Storage on the Microbial and Bio-chemical Quality of Sutchi Cat Fish (Pangasius hypophthalmus)

Gamma irradiation is known as an effective method to reduce microbial contamination in food products. Its application in seafood food not only enhances safety and quality but also extends shelf life, thereby minimizing post-harvest losses. This study focuses on evaluating the combined effect of low dose gamma irradiation and low-temperature storage on the quality and shelf life of fresh Sutchi Catfish (Pangasius hypophthalmus). The fish samples were subjected to different gamma irradiation doses (0.0 kGy, 1.0 kGy, 3.0 kGy, and 5.0 kGy) and then stored under refrigerated conditions (4°C) and frozen conditions (-18°C). Both non-irradiated and irradiated samples were periodically analyzed for microbial counts, including coliforms (total and fecal), total mesophilic bacteria, Salmonella, E. coli, and Staphylococcus aureus. The biochemical quality indices such as total volatile base nitrogen (TVB-N), pH, peroxide value (PV), and thiobarbituric acid reactive substances (TBARS) were also assessed at regular intervals. The findings revealed that the gamma irradiation and storage at low temperatures significantly (p < 0.05) reduced microbial populations, with higher irradiation doses resulting in greater reductions. Chemical quality indicators in irradiated samples were notably better maintained compared to the control samples under both storage conditions. The study concluded that combining gamma irradiation with refrigeration or freezing effectively minimized microbial loads and preserved biochemical quality. This approach extended the shelf life of the fish up to 21 days in refrigeration and 90 days under frozen storage conditions.

Cytokine storm modulation using cholecalciferol and low dose gamma radiation in Escherichia coli infected mice.

This work investigates the efficiency of cholecalciferol and low dose gamma radiation in modulating cytokine storm through their impact on inflammatory and anti-inflammatory cytokine and protecting against lung and liver injuries. Male Swiss albino mice were exposed to 0.2 Gy gamma radiation/week for four consecutive weeks then injected intraperitoneally (i.p) with a single dose of 8.3 × 106 CFU Escherichia coli/g b.w. then injected i.p. with 1.0 mg/kg cholecalciferol (Vit D3) for 7 days starting 4 h after E. coli injection. The results revealed that Cholecalciferol and low dose gamma radiation caused significant depletion in the severity of E. coli infection (colony forming unit per milliliter), log10 of E. coli, Tumor necrosis factor alpha, Interleukin 6, VEGF, alanine aminotransferase, and aspartate aminotransferase levels and significant elevation in IL-10, IL-4, and HO-1. Immunohistochemical analysis of caspase-3 expression in lung tissue section showed low caspase-3 expression in cholecalciferol and low dose gamma radiation treated group. Histopathological examinations were performed in both lung and liver tissues which also emphasis the biochemical findings. Our results exhibit the importance of cholecalciferol and low dose gamma radiation in improving liver function and providing anti-inflammatory response in diseases causing cytokine storm.

Effect of different Gamma Rays doses on Seed Germination, Seedling parameter on local seed okra (Abelmoschus esculentus (L.)

The experiment was carried out to study the effect of different gamma irradiation in 100 -800 Gy with non-irradiated control on seed okra [Abelmoschus esculentus (L.). The study carried in Microbiology Dept. Directorate of Agricultural Research. Ministry of Science and Technology in 2020. The results showed that 100-300 Gy had positive effects with respect to all studied growth seeding parameters. With increase in radiation above 300 Gy a decreasing germination potential, The lowest germination percentage was recorded at 800Gy,speed of germination was noted by Control (10.00 day) followed by gamma irradiation dose 800(9.90 day) and the same dose was logged lowest mean daily germination (7.85 seed day-1 ), higher doses (800,700,600 ) Gy marked reduction in root, shoot length, vigor index , chlorophyll a chlorophyll b .and total chlorophyll. The result showed a decreasing of the fresh weight of okra when radiation dose was increased While, dry weight was increasing when the radiation dose was increased. This study shows that the low dose gamma radiation may enhance the germination rate and the seedling growth during the early seedling state of okra seeds.

Is acute low-dose gamma irradiation an effective elicitor for secondary metabolism in Leontopodium alpinum (Cass.) callus culture?

Is acute low-dose gamma irradiation an effective elicitor for secondary metabolism in Leontopodium alpinum (Cass.) callus culture?

Apigenin and Exposure to Low Dose Gamma Radiation Ameliorate Acetic Acid-Induced Ulcerative Colitis in Rats.

Ulcerative colitis (UC) is an inflammatory bowel disease involving chronic and recurring colon inflammation. Current management protocols are limited by adverse effects or short-term symptomatic relief. We aimed to investigate the possible therapeutic prospect of low dose gamma (γ) irradiation or apigenin treatment in acetic acid-induced UC in rats. Induction of UC was carried out by installation of acetic acid intra-rectally. One hour post-induction, rats received a sole dose of γ-radiation (0.5Gray) or were treated with apigenin (3mg/kg/day, peroral) for 7 successive days. Antioxidant and anti-inflammatory effects of both agents were assessed via determination of colon malondialdehyde (MDA), reduced glutathione (GSH), total nitrate/nitrite (NOx), mucosal addressin cell adhesion molecule-1 (MAdCAM-1), and interleukin-1beta (IL-1β) contents as well as myeloperoxidase (MPO) activity. Body weight (BW), colon weight/length (W/L) ratio, disease activity index (DAI), and histopathological changes were evaluated. Gamma irradiation and apigenin significantly ameliorated the acetic acid-induced biochemical and histopathological changes. Both therapeutic approaches significantly restored colon contents of the investigated biomarkers. They modulated BW, colon W/L ratio and DAI. This study proposes low dose γ-irradiation as a new therapeutic candidate for the management of UC. We also concluded that apigenin exhibited therapeutic benefits in UC management.

Impairment of placental angiogenesis in rats treated with saffron: The role of low dose gamma irradiation

Impairment of placental angiogenesis in rats treated with saffron: The role of low dose gamma irradiation

INFLUENCE OF GAMMA RADIATION ON EUTECTIC PHASE AREA AND HARDNESS PROPERTIES OF SAC305 SOLDER

Gamma radiation plays an important role in changing the properties and behavior of the materials. In this present work, the correlation between the intermetallic compound (IMC), eutectic phase area and hardness of the lead-free solder radiated with low dose gamma radiation were investigated. Using a technique known as stencil printing, the solder paste was manually applied to the printed circuit board (PCB). Subsequently, the solder PCB was reflow soldered at 260 ˚C and allowed to expose to a variation of low dose gamma radiation (5, 10, 15, 20 and 25 Gy). Prior to the indentation test, the samples were subjected to a metallographic process to examine the cross-section of the interface between the solder and the substrate. The microstructure, intermetallic compound (IMC) and hardness properties were captured and measured via optical microscope and nanoindentation test equipment respectively. The IMC thickness of the solders increased with increasing radiation exposure, suggesting that gamma radiation influenced the morphologies of the SAC305 solder, leading to a change in IMC thickness. The effect of the exposure of various doses of gamma on the phase distribution of the eutectic in the SAC305 solder was also investigated. The eutectic phase area showed a comparable trend in the value of hardness obtained. The eutectic area increased up to 29.65 % after being radiated by 15 Gy of gamma, then decreased to 17.66 % when exposed to 25 Gy. From the nanoindentation test, the load-displacement curves extracted the value of hardness of the SAC305 solder.

Detection of Low Dose-Gamma Irradiated Spices by Photostimulated Luminescence (PSL) Technique

Photostimulated Luminescence (PSL) has been widely used as a rapid screening technique for the detection of various irradiated foods. This study aims to investigate the efficacy of the PSL technique in the detection of low dose-gamma irradiated spices available in the Malaysia market. Samples of clove, coriander, fenugreek, turmeric powder and curry powder were irradiated at very low doses; 0 (control), 0.2, 0.5 and 1 kGy using Cobalt-60 as a source. PSL measurements and analysis were undertaken under subdued lighting following EN 13751 methods. The PSL value in the form of photon counts (PCs/60s) of all samples as a function of the irradiation dose after 7 days of storage were determined which revealed that the PSL value increases proportionally to the radiation dose applied. The PSL also was able to discriminate between the non-irradiated (<700 PCs/60s, negative) and irradiated (>5000 PCs/60s, positive) samples after 7 days of storage. Coriander generates the highest PCs at the lowest dose (0.2 kGy) and highest dose (1 kGy) after that storage period. The PSL value of all spice samples is considered accurate and consistent at all irradiation doses. This technique is highly reliable for the detection of irradiated spices available in the Malaysia market.

Low Dose Gamma Irradiation of Trypanosoma evansi Parasites Identifies Molecular Changes That Occur to Repair Radiation Damage and Gene Transcripts That May Be Involved in Establishing Disease in Mice Post-Irradiation.

The protozoan parasite Trypanosoma evansi is responsible for causing surra in a variety of mammalian hosts and is spread by many vectors over a wide geographical area making it an ideal target for irradiation as a tool to study the initial events that occur during infection. Parasites irradiated at the representative doses 100Gy, 140Gy, and 200Gy were used to inoculate BALB/c mice revealing that parasites irradiated at 200Gy were unable to establish disease in all mice. Cytokine analysis of mice inoculated with 200Gy of irradiated parasites showed significantly lower levels of interleukins when compared to mice inoculated with non-irradiated and 100Gy irradiated parasites. Irradiation also differentially affected the abundance of gene transcripts in a dose-dependent trend measured at 6- and 20-hours post-irradiation with 234, 325, and 484 gene transcripts affected 6 hours post-irradiation for 100Gy-, 140Gy- and 200Gy-irradiated parasites, respectively. At 20 hours post-irradiation, 422, 381, and 457 gene transcripts were affected by irradiation at 100Gy, 140Gy, and 200Gy, respectively. A gene ontology (GO) term analysis was carried out for the three representative doses at 6 hours and 20 hours post-irradiation revealing different processes occurring at 20 hours when compared to 6 hours for 100Gy irradiation. The top ten most significant processes had a negative Z score. These processes fall in significance at 140Gy and even further at 200Gy, revealing that they were least likely to occur at 200Gy, and thus may have been responsible for infection in mice by 100Gy and 140Gy irradiated parasites. When looking at 100Gy irradiated parasites 20 hours post-irradiation processes with a positive Z score, we identified genes that were involved in multiple processes and compared their fold change values at 6 hours and 20 hours. We present these genes as possibly necessary for repair from irradiation damage at 6 hours and suggestive of being involved in the establishment of disease in mice at 20 hours post-irradiation. A potential strategy using this information to develop a whole parasite vaccine is also postulated.

Combination treatment including irradiation improved the keeping quality of bitter melon (Momordica charantia L) with retention of functional bioactives while fulfilling phytosanitary requirement for export

Present work dealt with development of a combination process for prolonged extension of shelf life of whole as well as minimally processed bitter gourd samples. In this treatment, GRAS chemicals were used for extension of shelf life while radiation processing was optimized to use as a phytosanitary treatment. The whole process involved dipping the bitter gourd samples in sodium hypochlorite (200 ppm) at 52 °C for 10 min (as disinfectant treatment) followed by potassium metabisulphite at optimal concentration (0.5%) for 10 min at 26 ± 2 °C (as an antifungal treatment). Finally, the samples were exposed to low dose (1 kGy) gamma irradiation treatment as a phytosanitary measure. An extended shelf life of 30 days was obtained, while improving the microbiological quality and retaining the colour, textural and sensory qualities. Combination process significantly enhanced the total phenolic content in processed samples during the storage period as compared to unprocessed control. Antioxidant activities of processed samples in terms of FRAP and DPPH radical scavenging activity as well as the antimutagenic activity were also conserved in treated samples. Thus, the treatment developed enhanced the storage life of processed bitter gourd stored at 4 ± 2 °C while satisfying the phytosanitary requirement for export especially to the countries requiring longer voyage time.

Inactivation of stressed Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes in hummus using low dose gamma irradiation.

Hummus is a popular dip in the Middle East region prepared by mixing the boiled chickpeas with tahini and other ingredients, and because its consumption has increased world-wide some notoriety has developed following an increase in the incidence of hummus-related illness outbreaks and recalls. The objectives of the current research were (i) to study the efficiency of low dose gamma irradiation to inhibit Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in hummus, and (ii) to assess the effect of environmental stresses namely cold, heat, and desiccation on the resistance of these pathogens to gamma irradiation. The samples of hummus were prepared and then individually inoculated with approximately 7.0 log CFU/g of unstressed or cold-, heat-, or desiccated-stressed cocktail cultures of each of E. coli O157:H7, S. enterica, and L. monocytogenes. The inoculated samples were then exposed to gamma irradiation at doses of 0.1 to 0.6 kGy. The numbers of unstressed E. coli O157:H7, S. enterica, and L. monocytogenes were decreased by 0.6-3.9, 0.7-2.9, and 1.0-3.0 log CFU/g, respectively, by irradiation treatment. The resistance of E. coli O157:H7 to gamma irradiation was not affected by desiccation, heat, and cold stresses. However, the pre-exposure of S. enterica and L. monocytogenes cells to these stresses reduced their resistance toward gamma irradiation. PRACTICAL APPLICATION: Gamma irradiation is a non-thermal treatment that can be used in food processing to ensure food safety and quality. The current study proved that low levels (≤0.6 kGy) of gamma irradiation can effectively decrease the risk of unstressed and cold-, heat-, or desiccation-stressed Salmonella enterica, Listeria monocytogenes, or Escherichia coli O157:H7 in hummus.

Gamma radiation effects on the survival and reduction of Listeria monocytogenes on carrot and tomato

Assessment of pathogen survival is important for food safety. Listeria monocytogenes causes significant produce and food contamination worldwide. The objective of this research was to assess survival and reduction of L. monocytogenes on post-harvest carrot and tomato subjected to low-dose radiation at different storage temperatures and times. Radiation levels of 0, 0.25, 0.50, 0.75, and 1 kGy were applied on produce inoculated with L. monocytogenes. Gamma radiation reduced Listeria populations by 5.9 logs on carrot and 3.9 logs on tomato at 3 days of storage (5 °C), while reductions were 4.4 and 4.0 logs on carrot and tomato, respectively; at 7 storage days (5 °C). At 20 °C, Listeria reductions were 2.8 logs on carrot and 4.2 logs on tomato (3 storage days) and pathogen decreases were 2.2 logs on carrot and 2.9 logs on tomato (7 storage days). Although pathogen reductions by radiation treatment varied with storage temperatures and days, the linear decreases were significant as the dosage increased from 0.25 to 1.0 kGy, implying that treatments were efficacious for pathogen inactivation. As low dose gamma radiation (1 kGy) showed substantial reduction of Listeria monocytogenes on fresh carrot and tomato, thus, use of low dose low dose gamma radiation can improve the post-harvest safety of carrot and tomato.

Impairment of Placental Angiogenesis in Rats Treated with Saffron: The Role of Low Dose Gamma Irradiation

Impairment of Placental Angiogenesis in Rats Treated with Saffron: The Role of Low Dose Gamma Irradiation

High-Performance and Radiation-Hardened Solution-Processed ZrLaO Gate Dielectrics for Large-Area Applications.

Radiation hardness is important for electronics operating in harsh radiation environments such as outer space and nuclear energy industries. In this work, radiation-hardened solution-processed ZrLaO thin films are demonstrated. The radiation effects on solution-processed ZrLaO thin films and InOx/ZrLaO thin-film transistors (TFTs) were systemically investigated. The Zr0.9La0.1Oy thin films demonstrated excellent radiation hardness with negligible roughness, composition, electrical property, and bias-stress stability degradation after radiation exposure. The metal-oxide-semiconductor capacitors (MOSCAPs) based on Zr0.9La0.1Oy gate dielectrics exhibited an ultralow flat band-voltage (VFB) sensitivity of 0.11 mV/krad and 0.19 mV/krad under low dose and high dose gamma irradiation conditions, respectively. The low dose condition had a 103 krad (SiO2) total dose and a 0.12 rad/s low dose rate, whereas the high dose condition had a 580 krad total dose and a 278 rad/s high dose rate. Furthermore, InOx/Zr0.9La0.1Oy thin-film transistors (TFTs) exhibited a large Ion/Ioff of 2 × 106, a small subthreshold swing (SS) of 0.11 V/dec, a small interface trap density (Dit) of 1 × 1012 cm-2, and a 0.16 V threshold shift (ΔVTH) under 3600 s positive bias-stress (PBS). InOx/Zr0.9La0.1Oy TFT-based resistor-loaded inverters demonstrated complete swing behavior, a static output gain of 13.3 under 4 V VDD, and an ∼9% radiation-induced degradation. Through separate investigation of the radiation-induced degradation on the semiconductor layer and dielectric layer of TFTs, it was found that radiation exposure mainly generated oxygen vacancies (Vo) and increased electron concentration among gate oxide. Nevertheless, the radiation-induced TFT instability was mainly related to the semiconductor layer degradation, which could be possibly suppressed by back-channel passivation. The demonstrated results indicate that solution-processed ZrLaO is a high-potential candidate for large-area electronics and circuits applied in harsh radiation environments. In addition, the detailed investigation of radiation-induced degradation on solution-processed high-k dielectrics in this work provided clear inspiration for developing novel flexible rad-hard dielectrics.

Modulation of PTZ-induced convulsions in rats using topiramate alone or combined with low dose gamma irradiation: Involving AKT/m-TOR pathway

ABSTRACT The current study evaluates the anticonvulsant effect low dose whole body gamma irradiation (LDR) alone or combined with topiramate (TOP) against pentylenetetrazol (PTZ)-induced convulsions. Male Wister rats received either saline or pentylenetetrazole (75 mg/kg i.p.). The other three groups were pretreated with single low dose radiation (o.5 Gy), Topiramate (50 mg/kg, p.o., 7 days) and TOP with LDR respectively before PTZ injection. Racine’ score, latency and duration of the convulsions were assessed. Glutamate and GABA were measured. As well as AKT/m-TOR signalling pathway including AKT (protein kinase –B), m-TOR (mammalian target of rapamycin), protein S6 and caspase3 were also assessed. Measurements of markers of oxidative stress including MDA (malondialdehyde), GSH (glutathione) and NO (nitric oxide) were carried out. Histological examinations of hippocampi were done. Results: PTZ produced behavioural changes (high Racine score, short latency and long duration. It elevated MDA and NO contents, while reduced GSH content. TOP treatment alone or combined with LDR ameliorated the PTZ-induced convulsions and caused significant improvement in behavioural changes, brain mediators, m-TOR pathway, oxidative stress and histological pictures in hippocampal regions. Histopathological examinations of the normal group showed normal structure with intact cells, while PTZ- treated rats exhibited necrosis, pyknosis and atrophy of pyramidal cells. The histological findings corroborated with the amendment of biochemical parameters. Conclusions The positive effects of LDR could offer a possible contributor in management of convulsions due to modulation of AkT/m-TOR signalling pathway, reduction of oxidative stress and modulation of brain amino acids. LDR improved the oxidative stress side effects of topiramate. Highlights Male Wistar rats were treated with topiramate 50 mg/kg p.o. for 7 days. on the 6th day of topiramate treatment, rats were exposed to a single low dose whole body gamma radiation (0.5 Gy). on the 7th day of topiramate treatment, rats were injected with pentylenetetrazole 75 mg/kg i.p. 2h after the 7th dose of TOP to illustrate the protective effects of TOP against acute convulsions induced by PTZ. Low dose whole body gamma irradiation purveyed novel anticonvulsant activity which could offer a possible contributor in the basic management of convulsions to avoid side effects of traditional anticonvulsant drugs such as liver and kidney impairments.

Low dose gamma irradiation pretreatment modulates the sensitivity of CNS to subsequent mixed gamma and neutron irradiation of the mouse head

ABSTRACТ Purpose: To explore if the total body γ-irradiation at a dose of 0.1 Gy 7 days prior to acute mixed γ, n-irradiation of the head at the dose of 1 Gy can reduce the harmful effects of neutron irradiation on the hippocampal functions, neuroinflammation and neurogenesis. Materials and methods: Mice were exposed to γ-radiation alone, mixed γ,n-radiation or combined γ-rays and γ,n-radiation 7 days after γ-irradiation. Two months post-irradiation, mice were tested in Open Field and in the Morris water maze. The content of microglia, astrocytes, proliferating cells and cytokines TGF-β, TNF-α, IL-1β, GFAP levels, hippocampal BDNF, NT-3, NT-4, NGF mRNA expression were evaluated. Results: Two months after combined irradiation, we observed impaired hippocampus-dependent cognition, which was not detected in mice exposed to γ,n-irradiation. Combined exposure and γ,n-irradiation led to a significant increase in the level of activated microglia and astrocytes in the brains. The level of pro- and anti-inflammatory cytokines in the brain and hippocampal neurotrophine's genes changed differenly after the combined exposure and γ,n-irradiation. The quantity of DCX-positive cells was reduced after γ,n-irradiation exposer alone, but increased after combined irradiation. Conclusions: Our results indicate radio-adaptive responses in brains of mice that were exposed to low-dose gamma irradiation 7 days prior to acute 1 Gy γ,n-irradiation.

Hormesis effects of gamma radiation on growth of quinoa (Chenopodium quinoa)

Purpose Quinoa is an annual plant that grows well in high altitude regions with high radiation and ultraviolet intensity. It has known that high-dose radiation damages living organisms, but low-dose radiation also has a beneficial effect. Therefore, the purpose of this study is to investigate the hormesis effect of gamma-ray on quinoa by growth analysis and hyperspectral imaging. Materials and methods Quinoa seeds were irradiated at 50, 100, and 200 Gy emitted by 60CO. Subsequently, the seeds were germinated and transplanted into pots, then conducted growth analysis and physiological evaluation every week, and hyperspectral imaging. Photosynthetic ability was measured at 35 days after transplanting (DAT), and the plants for each dose were divided into aerial and underground parts for biomass evaluation at 91 DAT. Various vegetation indices were estimated from 14 to 35 DAT by hyperspectral analysis, and the specific bands were extracted based on the PLS model using plant height, SPAD value, and chlorophyll fluorescence parameters. Results We found that plant height and biomass were increased in quinoa plants treated with a low dose (50 Gy) as compared to control. Chlorophyll content and chlorophyll fluorescence were not different between doses at the early growth stage, but as growth progressed, the plant irradiated at 200 Gy began to be lower. The photosynthetic ability of the quinoa plant treated at 50 Gy was greater than other plants at 35 DAT. The vegetation indices related to the pigment status also were higher in the plants treated by irradiation at 50 Gy than the plants grown in other doses treatment units at the beginning of the growth. Using the PLS model we collected sensitive band wavelengths from hyperspectral image analysis. Among the collected bands, eight bands closely related to plant height, nine bands to chlorophyll content, and ten bands to chlorophyll fluorescence were identified. Conclusion Our results showed that the growth and physiological parameters of quinoa treated by low dose gamma irradiation to seeds were greater than that of control as well as the plant with higher doses. These findings confirm that the positive changes in the characteristics of quinoa with low dose radiation indicated that hormesis occurs at 50 Gy radiation.

Low dose gamma irradiation attenuates cyclophosphamide-induced cardiotoxicity in rats: role of NF-κB signaling pathway

Purpose Cyclophosphamide (Cyp) is one of the most commonly used, wide spectrum chemotherapeutic agents. Cyp has multi-organ toxicities that are dose limiting, thus it’s mostly used in chemotherapeutic combinations. Radiation is well known as a hazardous sort of energy, recent studies are interested in studying the beneficial therapeutic effects of low-dose gamma radiation. This study examined the protective effect of two different doses/dose-rates of irradiation either alone or combined with telmisartan against Cyp-induced cardiotoxicity. Materials and methods Rats were divided into seven groups; (1): Control, (2): Cyp, (3–4): 0.05 Gy low dose rate (LDR) irradiation, 0.25 Gy high dose rate (HDR) irradiation, respectively, prior to Cyp dose, (5–7): telmisartan either alone or with 0.05 Gy LDR-irradiation or 0.25 Gy HDR-irradiation, respectively, prior to Cyp dose. The current investigation studied the effect of Cyp alone or combined with different treatment regimens on serum cTn-I and LDH, nuclear factor-κB (NF-κB) pathway (p65/IκB/IKK-α/IKK-ß) in the myocardium. Pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α were assessed in addition to histopathological examination of the heart. Results Low-dose irradiation attenuated cardiac enzymes, pro-inflammatory cytokines, NF-κB content, and histology, in both low and HDRs. Furthermore, the combination of low-dose irradiation with telmisartan (an angiotensin-II receptor type-1 blocker and a known cardio-protective drug) offered the best histological results. Conclusions Low-dose irradiation-induced amelioration is partially but not completely through canonical activation of NF-κB, and may have another atypical pathway. While telmisartan probably ameliorates NF-κB totally through canonical pathway.

Comparing the efficacy of γ- and electron-irradiation of PBMCs to promote secretion of paracrine, regenerative factors

Cell-free secretomes represent a promising new therapeutic avenue in regenerative medicine, and γ-irradiation of human peripheral blood mononuclear cells (PBMCs) has been shown to promote the release of paracrine factors with high regenerative potential. Recently, the use of alternative irradiation sources, such as artificially generated β- or electron-irradiation, is encouraged by authorities. Since the effect of the less hazardous electron-radiation on the production and functions of paracrine factors has not been tested so far, we compared the effects of γ- and electron-irradiation on PBMCs and determined the efficacy of both radiation sources for producing regenerative secretomes. Exposure to 60 Gy γ-rays from a radioactive nuclide and 60 Gy electron-irradiation provided by a linear accelerator comparably induced cell death and DNA damage. The transcriptional landscapes of PBMCs exposed to either radiation source shared a high degree of similarity. Secretion patterns of proteins, lipids, and extracellular vesicles displayed similar profiles after γ- and electron-irradiation. Lastly, we detected comparable biological activities in functional assays reflecting the regenerative potential of the secretomes. Taken together, we were able to demonstrate that electron-irradiation is an effective, alternative radiation source for producing therapeutic, cell-free secretomes. Our study paves the way for future clinical trials employing secretomes generated with electron-irradiation in tissue-regenerative medicine.

Identification of Ferroptosis Biomarker in AHH-1 Lymphocytes Associated with Low Dose Radiation.

The impact of long-term low-dose radiation on human health has always been a concern. Long-term low-dose gamma radiation causes cells continuous injury and causes chromosomal mutations to greatly increase the chance of cancer. Because it is significant to identify biomarkers for long-term low-dose gamma radiation, we investigate the influence of low dose rate on the gene expressions in the AHH-1 lymphocytes cell line (AHH-1 cells) for long-term irradiation. Different dose rates (7, 14, 26, 34, and 43 μGy h-1) of irradiation from gamma radiation in uranium tailings powder were used to irradiate AHH-1 lymphocytes. We used flow cytometry to test the apoptosis of AHH-1 lymphocytes at different dose rates and irradiation times (7-84 d). It was found that 14 μGy h-1 is the most sensitive dose rate of AHH-1 lymphocyte irradiation. The 7-, 14-, and 21-d (2.4, 4.8, and 7.2 mGy) irradiation groups were sensitive, and the 84-d (28.8 mGy) irradiation group was insensitive to low dose gamma radiation. Microarray analysis was conducted on the significantly differentially expressed genes (p<0.05) in the 2.4, 4.8, 7.2, and 28.8 mGy irradiation groups. We found that TFRC1, SLC3A2, SLC39A8, FTH1, ACSL4, and GPX4 are significant genes with low-dose radiation and were constituents of the ferroptosis signaling pathway. In the range of 0-4.8 mGy radiation dose, the expressions of these genes were downregulated with increasing radiation dose, while in the range of 4.8-28.8 mGy, its expression increased with increasing radiation dose. RT-PCR and Western blot were used to detect the mRNA and protein expression of these genes. The results were consistent with those from microarray analysis. Our findings indicate that expression of the TFRC, SLC3A2, SLC39A, FTH1, ACSL4, and GPX4 genes is sensitive to low-dose radiation, and they are main members of the ferroptosis signaling pathway. Therefore, there is a very important connection between ferroptosis and low-dose radiation, which has become a hot topic in international research. These results can provide reference to the effect of ferroptosis on human health with low-dose radiation.