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The presented study shows a simple way for optimization of extrusion process, which was used for deterioration of cyanogenic glycosides - antinutritive components of linseed, with minimum damage of essential Alpha-Linolenic Acid (ALA) at the same time. Extrusion of the material was done on a laboratory single screw extruder. Content of Hydrogen cyanide (HCN) as a measurement of cyanogenic glycosides in produced co-extrudate and fatty acid composition were determined, together with basic chemical analyses, which were done in accordance with AOAC methods. Statistical analysis showed that HCN content in the product was the most dependent (P= 0.0002) on quadratic influence of moisture content of starting material. The highest HCN content (126 mg kg-1) was measured at the lowest moisture content (7%) and the lowest screw speed (240 rpm). Low moisture content caused weak volatilization of HCN along with the evaporating water, which was intensified with higher values of moisture content. However, increase in moisture content from 11.5 to 16% slightly increased the amount of present HCN, due to the lower material viscosity. Extrusion process caused some changes in fatty acid composition, but even the highest degradation of ALA did not exceed 4%. Linear and quadratic influence of moisture content on ALA reduction was significant (P< 0.05), as well as quadratic influence of screw speed. Specific attention has to be paid to selecting appropriate levels of screw speed and moisture content of the material which contains linseed, in order to achieve both detoxification of linseed and preservation of essential fatty acids. [ABSTRACT FROM AUTHOR]

The estrogenic mycotoxin zearalenone (ZEN) is a common contaminant of animal feed. Effective strategies for the inactivation of ZEN in feed are required. The ZEN-degrading enzyme zearalenone hydrolase ZenA (EC 3.1.1.-, commercial name ZEN zyme ® , BIOMIN Holding GmbH, Getzersdorf, Austria) converts ZEN to hydrolyzed ZEN (HZEN), thereby enabling a strong reduction in estrogenicity. In this study, we investigated the efficacy of ZenA added to feed to degrade ZEN in the gastrointestinal tract of three monogastric animal species, i.e., pigs, chickens, and rainbow trout. For each species, groups of animals received (i) feed contaminated with ZEN (chickens: 400 µg/kg, pigs: 200 µg/kg, rainbow trout: 2000 µg/kg), (ii) feed contaminated with ZEN and supplemented with ZenA, or (iii) uncontaminated feed. To investigate the fate of dietary ZEN in the gastrointestinal tract in the presence and absence of ZenA, concentrations of ZEN and ZEN metabolites were analyzed in digesta of chickens and rainbow trout and in feces of pigs. Upon ZenA administration, concentrations of ZEN were significantly decreased and concentrations of the degradation product HZEN were significantly increased in digesta/feces of each investigated animal species, indicating degradation of ZEN by ZenA in the gastrointestinal tract. Moreover, upon addition of ZenA to the diet, the concentration of the highly estrogenic ZEN metabolite α-ZEL was significantly reduced in feces of pigs. In conclusion, ZenA was effective in degrading ZEN to HZEN in the gastrointestinal tract of chickens, pigs, and rainbow trout, and counteracted formation of α-ZEL in pigs. Therefore, ZenA could find application as a ZEN-degrading feed additive for these animal species.

Purpose: The main goal of the research was to determine whether commercially available common dietary phytochemical supplements (curcumin, andrographolide, and d-limonene) have radiomodulatory effects on p53-competent human colonic epithelial cells., Methods: Clonogenic survival assays were used to characterize effects of the phytochemicals on cultured colonic epithelial cells (HCT116 p53 +/+ ) in direct irradiation or upon receipt of irradiated-cell conditioned media (for bystander effects). In direct irradiation, feeding regimen experiments included compound administration pre- and post-irradiation, which was used as a basis to define effects as radioprotective and radiomitigative, respectively. In the bystander effect experiments, either donor or recipient cell cultures were fed with the phytochemicals and bystander-induced clonogenic cell death was quantitatively evaluated. Dose challenge was in the range of 0.5 - 5 Gy using the gamma source (Cs-137)., Results: Curcumin, andrographolide, and d-limonene appeared to not exhibit radioprotective and radiomitigative properties in HCT116 p53 +/+ cells. D-limonene was found to induce radiosensitization in post-irradiation administration. All three compounds appeared not to modulate the radiation-induced bystander signal production and response in HCT116 p53 +/+ cells., Conclusions: Curcumin, andrographolide, and d-limonene are known to have many chemoprotective benefits. This work shows that they, however, did not protect colonic epithelial HCT116 p53 +/+ cells from radiation killing. As HCT116 p53 +/+ cells are tumourigenic in nature, this finding implies that these three dietary compounds would not reduce the killing efficacy of radiation in gastrointestinal tumorigenesis. The post-irradiation radiosensitizing effect of d-limonene was an intriguing observation worth further investigation.

This short review explores the utility and applications of CRISPR/Cas9 systems in radiobiology. Specifically, in the context of experimentally simulating genotoxic effects of Ionizing Radiation (IR) to determine the contributions from DNA targets and 'Complex Double-Stranded Breaks' (complex DSBs) to the IR response. To elucidate this objective, this review considers applications of CRISPR/Cas9 on nuclear DNA targets to recognize the respective 'nucleocentric' response. The article also highlights contributions from mitochondrial DNA (mtDNA) - an often under-recognized target in radiobiology. This objective requires accurate experimental simulation of IR-like effects and parameters with the CRISPR/Cas9 systems. Therefore, the role of anti-CRISPR proteins in modulating enzyme activity to simulate dose rate - an important factor in radiobiology experiments is an important topic of this review. The applications of auxiliary domains on the Cas9 nuclease to simulate oxidative base damage and multiple stressor experiments are also topics of discussion. Ultimately, incorporation of CRISPR/Cas9 experiments into computational parameters in radiobiology models of IR damage and shortcomings to the technology are discussed as well. Altogether, the simulation of IR parameters and lack of damage to non-DNA targets in the CRISPR/Cas9 system lends this rapidly emerging tool as an effective model of IR induced DNA damage. Therefore, this literature review ultimately considers the relevance of complex DSBs to radiobiology with respect to using the CRISPR/Cas9 system as an effective experimental tool in models of IR induced effects., Competing Interests: Declaration of Competing Interest The author(s) declared no conflicts of interest with respect to the research, authorship and/or publication of this article., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

This short review explores the utility and applications of CRISPR/Cas9 systems in radiobiology. Specifically, in the context of experimentally simulating genotoxic effects of Ionizing Radiation (IR) to determine the contributions from DNA targets and 'Complex Double-Stranded Breaks' (complex DSBs) to the IR response. To elucidate this objective, this review considers applications of CRISPR/Cas9 on nuclear DNA targets to recognize the respective 'nucleocentric' response. The article also highlights contributions from mitochondrial DNA (mtDNA) - an often under-recognized target in radiobiology. This objective requires accurate experimental simulation of IR-like effects and parameters with the CRISPR/Cas9 systems. Therefore, the role of anti-CRISPR proteins in modulating enzyme activity to simulate dose rate - an important factor in radiobiology experiments is an important topic of this review. The applications of auxiliary domains on the Cas9 nuclease to simulate oxidative base damage and multiple stressor experiments are also topics of discussion. Ultimately, incorporation of CRISPR/Cas9 experiments into computational parameters in radiobiology models of IR damage and shortcomings to the technology are discussed as well. Altogether, the simulation of IR parameters and lack of damage to non-DNA targets in the CRISPR/Cas9 system lends this rapidly emerging tool as an effective model of IR induced DNA damage. Therefore, this literature review ultimately considers the relevance of complex DSBs to radiobiology with respect to using the CRISPR/Cas9 system as an effective experimental tool in models of IR induced effects., Competing Interests: Declaration of Competing Interest The author(s) declared no conflicts of interest with respect to the research, authorship and/or publication of this article., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

Exposures to ionizing radiation can cause depletion in stem cell reservoirs and lead to chronic injury processes that exacerbate carcinogenic and inflammatory responses. Therefore, radioprotective measures, against both acute and chronic biological effects of radiation, require frequent intake of nontoxic natural products, which have practical oral administration. The goal of this study was to characterize the radioprotective, radiomitigative and radiation-induced bystander effect-inhibiting properties of endogenous metabolites: phenylacetate, ursodeoxycholate and tauroursodeoxycholate. Compounds were administered pre- and postirradiation as well as in donor and recipient bystander flasks to analyze whether these might adequately protect against radiation injury as well as facilitate recovery from the exposures. The clonogenic HCT116 p53 wild-type cancer cell line in this study shares characteristics of stem cells, such as high reproductive viability, which is an effective marker to demonstrate compound effectiveness. Clonogenic assays were therefore used to characterize radioprotective, radiomitigative and bystander inhibiting properties of treatment compounds whereby cellular responses to radiation were quantified with macroscopic colony counts to measure cell survival in flasks. The results were statistically significant for phenylacetate and tauroursodeoxycholate when administered preirradiation, conferring radioprotection up to 2 Gy, whereas administration postirradiation and in bystander experiments did not confer radioprotection in vitro . These findings suggest that phenylacetate and tauroursodeoxycholate might be effective radioprotectors, although they possess no radiomitigative properties.

Chemoprophylatic strategies against development of multifactorial diseases utilize compounds to block the multistep events in chronic inflammation and carcinogenesis. The successful chemopreventative candidate must therefore selectively inhibit growth of transformed cells and be administered frequently to confer maximal protection with minimal side effects. In addition to synthetic and exogenous natural compounds, endogenous metabolites represent another class of compounds that exhibit anticarcinogenic and anti-inflammatory properties contributing to proper cell function. To assess the effectiveness of these compounds warrants an understanding of their cytotoxic mode of action. In this study, p53 variant human colon carcinoma cell lines were chronically exposed to varying concentrations of the endogenous metabolites-phenyl acetate, ursodeoxycholate, and tauroursodeoxycholate-to determine the role of p53-induced cytotoxicity, with p53 mutant and deficient cell lines representing precancerous lesions. Cytotoxicity was assessed using clonogenic assays, and macroscopic colony counts were used to quantify cell survival. The results demonstrate that the bile acids, ursodeoxycholate and tauroursodeoxycholate, exhibit selective cytotoxicity toward nonfunctional p53 cell lines suggesting a p53-mediated role in inhibition of cell clonogenicity and potential chemopreventative properties. Although each compound displays this described effect, the tauroursodeoxycholate demonstrates high significance suggesting it might have practical uses in vivo., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no conflicts of interest with respect to the research, authorship and/or publication of this article.

Chemoprevention strategies employ the use of compounds to inhibit the initiation, promotion, and progression phases of carcinogenesis. The successful chemopreventative candidate must therefore (1) selectively inhibit growth of transformed cells and (2) be administered on a frequent basis to confer maximal protection. Phytochemicals are a subclass of bioactive plant secondary metabolites that exhibit antioxidative, anticarcinogenic, and anti-inflammatory properties contributing to proper cell function. To assess the effectiveness of these compounds warrants an understanding of their cytotoxic mode of action. In this study, p53 variant human colon carcinoma cell lines were chronically exposed to varying concentrations of the phytochemicals-curcumin, andrographolide, and d-limonene-to determine the role of p53-induced cytotoxicity, with p53-mutant and p53-deficient cell lines representing precancerous lesions. Cytotoxicity was assessed using clonogenic assays and macroscopic colony counts were used to quantify cell survival. The results demonstrate that each phytochemical exhibits selective cytotoxicity toward nonfunctional p53 cell lines, suggesting a p53-mediated role in inhibition of cell clonogenicity and potential chemopreventative properties. Although each compound displays this described effect, only the d-limonene demonstrates considerable chemoprotection, suggesting it might have practical implications in vivo., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The question of whether bystander and abscopal effects are the same is unclear. Our experimental system enables us to address this question by allowing irradiated organisms to partner with unexposed individuals. Organs from both animals and appropriate sham and scatter dose controls are tested for expression of several endpoints such as calcium flux, role of 5HT, reporter assay cell death and proteomic profile. The results show that membrane related functions of calcium and 5HT are critical for true bystander effect expression. Our original inter-animal experiments used fish species whole body irradiated with low doses of X-rays, which prevented us from addressing the abscopal effect question. Data which are much more relevant in radiotherapy are now available for rats which received high dose local irradiation to the implanted right brain glioma. The data were generated using quasi-parallel microbeams at the biomedical beamline at the European Synchrotron Radiation Facility in Grenoble France. This means we can directly compare abscopal and "true" bystander effects in a rodent tumour model. Analysis of right brain hemisphere, left brain and urinary bladder in the directly irradiated animals and their unirradiated partners strongly suggests that bystander effects (in partner animals) are not the same as abscopal effects (in the irradiated animal). Furthermore, the presence of a tumour in the right brain alters the magnitude of both abscopal and bystander effects in the tissues from the directly irradiated animal and in the unirradiated partners which did not contain tumours, meaning the type of signal was different., (Copyright © 2015. Published by Elsevier Ltd.)