scholarly journals Radiation-Induced Bystander Effect: Loss of Radioprotective Capacity of Rosmarinic Acid In Vivo and In Vitro

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 231
Author(s):  
Amparo Olivares ◽  
Miguel Alcaraz-Saura ◽  
Daniel Gyingiri Achel ◽  
Juan de Dios Berná-Mestre ◽  
Miguel Alcaraz
Keyword(s):  
Cell Survival ◽  
Rosmarinic Acid ◽  
Bystander Effect ◽  
In Vitro Assays ◽  
X Rays ◽  
Direct Exposure ◽  
Radiation Induced ◽  
Radiation Induced Bystander Effect

In radiation oncology, the modulation of the bystander effect is a target both for the destruction of tumor cells and to protect healthy cells. With this objective, we determine whether the radioprotective capacity of rosmarinic acid (RA) can affect the intensity of these effects. Genoprotective capacity was obtained by determining the micronuclei frequencies in in vivo and in vitro assays and the cell survival was determined by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay) (MTT) assay in three cell lines (PNT2, TRAMPC1 and B16F10), both in direct exposure to X-rays and after the production of radiation-induced bystander effect. The administration of RA in irradiated cells produced a decrease in the frequency of micronuclei both in vivo and in vitro, and an increase in cell survival, as expression of its radioprotective effect (p < 0.001) attributable to its ability to scavenge radio-induced free radicals (ROS). However, RA does not achieve any modification in the animals receiving serum or in the cultures treated with the irradiated medium, which expresses an absence of radioprotective capacity. The results suggest that ROS participates in the formation of signals in directly irradiated cells, but only certain subtypes of ROS, the cytotoxic products of lipid peroxidation, participate in the creation of lesions in recipient cells.

scholarly journals Biological Entanglement–Like Effect After Communication of Fish Prior to X-Ray Exposure

Dose-Response ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 155932581775006 ◽  
Author(s):  
Carmel Mothersill ◽  
Richard Smith ◽  
Jiaxi Wang ◽  
Andrej Rusin ◽  
Cris Fernandez-Palomo ◽  
...  
Keyword(s):  
Bystander Effect ◽  
X Ray ◽  
Before And After ◽  
Group A ◽  
Signal Production ◽  
Radiation Induced ◽  
Plant Photosynthesis ◽  
Radiation Induced Bystander Effect ◽  
Proteomic Responses

The phenomenon by which irradiated organisms including cells in vitro communicate with unirradiated neighbors is well established in biology as the radiation-induced bystander effect (RIBE). Generally, the purpose of this communication is thought to be protective and adaptive, reflecting a highly conserved evolutionary mechanism enabling rapid adjustment to stressors in the environment. Stressors known to induce the effect were recently shown to include chemicals and even pathological agents. The mechanism is unknown but our group has evidence that physical signals such as biophotons acting on cellular photoreceptors may be implicated. This raises the question of whether quantum biological processes may occur as have been demonstrated in plant photosynthesis. To test this hypothesis, we decided to see whether any form of entanglement was operational in the system. Fish from 2 completely separate locations were allowed to meet for 2 hours either before or after which fish from 1 location only (group A fish) were irradiated. The results confirm RIBE signal production in both skin and gill of fish, meeting both before and after irradiation of group A fish. The proteomic analysis revealed that direct irradiation resulted in pro-tumorigenic proteomic responses in rainbow trout. However, communication from these irradiated fish, both before and after they had been exposed to a 0.5 Gy X-ray dose, resulted in largely beneficial proteomic responses in completely nonirradiated trout. The results suggest that some form of anticipation of a stressor may occur leading to a preconditioning effect or temporally displaced awareness after the fish become entangled.

scholarly journals Oxidative Stress and Gene Expression Modifications Mediated by Extracellular Vesicles: An In Vivo Study of the Radiation-Induced Bystander Effect

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 156
Author(s):  
Rita Hargitai ◽  
Dávid Kis ◽  
Eszter Persa ◽  
Tünde Szatmári ◽  
Géza Sáfrány ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Lipid Peroxidation ◽  
Cell Cycle Arrest ◽  
Antioxidant Enzyme ◽  
Extracellular Vesicles ◽  
Bystander Effect ◽  
Cycle Arrest ◽  
Radiation Induced ◽  
Radiation Induced Bystander Effect

Radiation-induced bystander effect is a biological response in nonirradiated cells receiving signals from cells exposed to ionising radiation. The aim of this in vivo study was to analyse whether extracellular vesicles (EVs) originating from irradiated mice could induce modifications in the redox status and expression of radiation-response genes in bystander mice. C57BL/6 mice were whole-body irradiated with 0.1-Gy and 2-Gy X-rays, and EVs originating from mice irradiated with the same doses were injected into naïve, bystander mice. Lipid peroxidation in the spleen and plasma reactive oxygen metabolite (ROM) levels increased 24 h after irradiation with 2 Gy. The expression of antioxidant enzyme genes and inducible nitric oxide synthase 2 (iNOS2) decreased, while cell cycle arrest-, senescence- and apoptosis-related genes were upregulated after irradiation with 2 Gy. In bystander mice, no significant alterations were observed in lipid peroxidation or in the expression of genes connected to cell cycle arrest, senescence and apoptosis. However, there was a systemic increase in the circulating ROM level after an intravenous EV injection, and EVs originating from 2-Gy-irradiated mice caused a reduced expression of antioxidant enzyme genes and iNOS2 in bystander mice. In conclusion, we showed that ionising radiation-induced alterations in the cellular antioxidant system can be transmitted in vivo in a bystander manner through EVs originating from directly irradiated animals.

A in Vivo Assay for Standardizing Heparin Preparations

1979 ◽  
Vol 41 (03) ◽  
pp. 576-582
Author(s):  
A R Pomeroy
Keyword(s):  
In Vitro Assays ◽  
British Pharmacopoeia ◽  
In Vitro Method ◽  
Standard Preparation ◽  
Reliable Estimation ◽  
Assay Procedure ◽  
Accuracy And Precision ◽  
Heparin Preparation

SummaryThe limitations of currently used in vitro assays of heparin have demonstrated the need for an in vivo method suitable for routine use.The in vivo method which is described in this paper uses, for each heparin preparation, four groups of five mice which are injected intravenously with heparin according to a “2 and 2 dose assay” procedure. The method is relatively rapid, requiring 3 to 4 hours to test five heparin preparations against a standard preparation of heparin. Levels of accuracy and precision acceptable for the requirements of the British Pharmacopoeia are obtained by combining the results of 3 to 4 assays of a heparin preparation.The similarity of results obtained the in vivo method and the in vitro method of the British Pharmacopoeia for heparin preparations of lung and mucosal origin validates this in vivo method and, conversely, demonstrates that the in vitro method of the British Pharmacopoeia gives a reliable estimation of the in vivo activity of heparin.

Potentially Thrombogenic Materials in Factor IX Concentrates

1975 ◽  
Vol 33 (03) ◽  
pp. 617-631 ◽  
Author(s):  
H. S Kingdon ◽  
R. L Lundblad ◽  
J. J Veltkamp ◽  
D. L Aronson
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Factor Ix ◽  
In Vitro Assays ◽  
Substantial Agreement ◽  
Coefficient Of Correlation

SummaryFactor IX concentrates manufactured from human plasma and intended for therapeutic infusion in man have been suspected for some time of being potentially thrombogenic. In the current studies, assays were carried out in vitro and in vivo for potentially thrombogenic materials. It was possible to rank the various materials tested according to the amount of thrombogenic material detected. For concentrates not containing heparin, there was substantial agreement between the in vivo and in vitro assays, with a coefficient of correlation of 0.77. There was no correlation between the assays for thrombogenicity and the antithrombin III content. We conclude that many presently available concentrates of Factor IX contain substantial amounts of potentially thrombogenic enzymes, and that this fact must be considered in arriving at the decision whether or not to use them therapeutically.

In-silico Studies of Isolated Phytoalkaloid Against Lipoxygenase: Study Based on Possible Correlation

2018 ◽  
Vol 21 (3) ◽  
pp. 215-221
Author(s):  
Haroon Khan ◽  
Muhammad Zafar ◽  
Helena Den-Haan ◽  
Horacio Perez-Sanchez ◽  
Mohammad Amjad Kamal
Keyword(s):  
In Silico ◽  
Docking Studies ◽  
In Vivo Studies ◽  
In Vitro Assays ◽  
Chronic Obstructive ◽  
Lipoxygenase Inhibitors ◽  
Lipoxygenase Inhibition ◽  
In Silico Studies

Aim and Objective: Lipoxygenase (LOX) enzymes play an important role in the pathophysiology of several inflammatory and allergic diseases including bronchial asthma, allergic rhinitis, atopic dermatitis, allergic conjunctivitis, rheumatoid arthritis and chronic obstructive pulmonary disease. Inhibitors of the LOX are believed to be an ideal approach in the treatment of diseases caused by its over-expression. In this regard, several synthetic and natural agents are under investigation worldwide. Alkaloids are the most thoroughly investigated class of natural compounds with outstanding past in clinically useful drugs. In this article, we have discussed various alkaloids of plant origin that have already shown lipoxygenase inhibition in-vitro with possible correlation in in silico studies. Materials and Methods: Molecular docking studies were performed using MOE (Molecular Operating Environment) software. Among the ten reported LOX alkaloids inhibitors, derived from plant, compounds 4, 2, 3 and 1 showed excellent docking scores and receptor sensitivity. Result and Conclusion: These compounds already exhibited in vitro lipoxygenase inhibition and the MOE results strongly correlated with the experimental results. On the basis of these in vitro assays and computer aided results, we suggest that these compounds need further detail in vivo studies and clinical trial for the discovery of new more effective and safe lipoxygenase inhibitors. In conclusion, these results might be useful in the design of new and potential lipoxygenase (LOX) inhibitors.

Growth Retardation of Poorly Transfectable Tumor by Multiple Injections of Plasmids Encoding PE40 Based Targeted Toxin Complexed with Polyethylenimine

2020 ◽  
Vol 20 (4) ◽  
pp. 289-296
Author(s):  
Yuriy Khodarovich ◽  
Darya Rakhmaninova ◽  
German Kagarlitskiy ◽  
Anastasia Baryshnikova ◽  
Sergey Deyev
Keyword(s):  
Growth Retardation ◽  
Bystander Effect ◽  
Dna Encoding ◽  
Complex Preparation ◽  
Human Telomerase ◽  
Linear Polyethylenimine ◽  
Cag Promoter ◽  
Targeted Toxin

Background:: One of the approaches to cancer gene therapy relies on tumor transfection with DNA encoding toxins under the control of tumor-specific promoters. Methods:: Here, we used DNA plasmids encoding very potent anti-ERBB2 targeted toxin, driven by the human telomerase promoter or by the ubiquitous CAG promoter (pTERT-ETA and pCAG-ETA) and linear polyethylenimine to target cancer cells. Results:: We showed that the selectivity of cancer cell killing by the pTERT-ETA plasmid is highly dependent upon the method of preparation of DNA-polyethylenimine complexes. After adjustment of complex preparation protocol, cell lines with high activity of telomerase promoter can be selectively killed by transfection with the pTERT-ETA plasmid. We also showed that cells transfected with pTERT-ETA and pCAG-ETA plasmids do not exert any detectable bystander effect in vitro. Conclusion:: Despite this, three intratumoral injections of a plasmid-polyethylenimine complex resulted in substantial growth retardation of a poorly transfectable D2F2/E2 tumor in mice. There were no significant differences in anti-tumor properties between DNA constructs with telomerase or CAG promoters in vivo.

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