Toxicity of paclobutrazol-based pesticide on Lactuca sativa L.: germination, seedling development, and DNA damage.

Paclobutrazol, a fungicide of the triazole class, is widely used as an inducer of early flowering and fruiting by inhibiting gibberellin formation. However, biological assays using model organisms to evaluate their cytogenotoxic and mutagenic potential are still scarce. Therefore, this study aimed to investigate the effects of the commercial product Cultar® 250 SC (CP) and the pure substance (PBZ) on the germination and initial seedling development of Lactuca sativa L. (lettuce), in addition to evaluating the effects of CP on the mitotic activity and DNA, as we believe that PBZ has a greater toxic potential than CP on seed germination, and that the latter has cytogenotoxic and mutagenic effects on L. sativa. Lettuce seeds treated with CP and with PBZ in the doses of 0.25, 0.50, 1, 1.5, and 2 g L-1 showed significant reductions in germination rate, as well the CP reduced the root and initial development seedling development. PBZ showed greater inhibition of germination compared to CP. In direct exposure to PBZ, there was not sufficient seedling development for analysis, while in discontinuous treatment, there was inhibition of root growth (except for doses of 0.25 and 0.50 g L-1) and in the development of the aerial part. While no mitodepressive effect was observed in meristematic cells treated with CP, increased frequencies of chromosomal alterations, including condensed nuclei and micronuclei, were evident in both meristematic cells and the F1 region. The Comet assay further demonstrated higher levels of DNA damage at higher paclobutrazol doses, supporting the findings of increased micronucleus frequencies. Consequently, it can be concluded that the CP exhibits greater toxicity towards seed germination compared to lettuce seedlings, and PBZ has a greater toxic potential than CP in relation to these parameters. However, the impact of CP on seedlings was relatively minimal, as evidenced by their limited effects on development, cell proliferation, and DNA, suggesting a slight toxicity of this agent. Therefore, we infer that Cultar® 250 SC should be used with caution. Thus, this study emphasizes the importance of employing joint analyses to better elucidate and correlate the mechanisms of action of potentially toxic substances. Furthermore, it provides a basis for discussing the application of Cultar® 250 SC and seeking more sustainable alternatives in food production.

Aberrant nuclei with amplified DNA in cancer.

Gene amplification in the form of extrachromosomal DNA (ecDNA) or intrachromosomal homogenous staining regions (HSRs) is an emerging hallmark in cancer. Recent studies implicate abnormal nuclear structures in the biogenesis and evolution of amplified DNA. Here, we discuss how the interplay between aberrant nuclei and gene amplification drives cancer therapy resistance and metastasis.

Revealing the hidden threats: Genotoxic effects of microplastics on freshwater fish.

New evidence regarding the risks that microplastics (MP) ingestion pose to human and wildlife health are being revealed with progress made in ecotoxicological research. However, comprehensive and realistic approaches that evaluate multiple physiological responses simultaneously are still scarce despite their relevance to understand whole-organism effects. To address this information gap, we performed an experiment to assess the effects of MP on freshwater fish physiology from the molecular to the organismal level. Using a model species of global commercial importance (Cyprinus carpio) and MP type (recycling industry fragments), size (range between 125-1000 µm), and two concentrations of environmental relevance (0.75 and 8.25 µg/L). Experimental design included 5 blocks containing 3 treatment levels each one: control, low, and high MP concentration, with 6 fish each aquarium (5 blocks x 3 treatments x 6 fish per aquarium = 90 fish). Our results suggest that, under the experimental conditions applied, MP exposure did not cause adverse effects at the morphological (variation in size of gut), metabolic (variation of standard metabolic rate), or ecological (growth performance) levels. Nonetheless, we observed an increased frequency of micronucleated cells with increasing MP concentration (df = 42, t-value = 3.68, p-value < 0.001), showing the potential genotoxicity of MP, which can clearly harm fish health in long-term. Thus, despite being a highly resistant species, exposure to MP may generate negative effects in juvenile C. carpio at cellular or subcellular levels. Our findings highlight that the manifestation of MP effects may vary over time, emphasizing the need for future studies to consider longer exposure durations in experimental designs.

Isolation and comparative genotoxicity screening of trichokonins VI and VIII on CHO-K1 cells.

Peptaibols are fungal peptides that exhibit efficacy against pathogen microorganisms. Trichokonin VI (TK-VI) and trichokonin VIII (TK-VIII) are known peptaibols isolated from the endolichenic fungi Hypocrea sp. Previous investigations reported that trichokonin VI presents antiproliferative effects on tumor cells. This study is pioneering in elucidating the genotoxic effects of TK-VI and TK-VIII, contributing to the thorough assessment of their safety as potential therapeutic agents. The present investigation aimed to evaluate the genotoxicity of TK-VI and TK-VIII on CHO-K1 cells. Cytotoxicity was evaluated using the XTT assay and clonogenic survival assays, followed by evaluation of DNA damage using the comet assay and micronucleus test conducted in vitro. The XTT assay results indicated IC50 values of 10.30 µM and 9.89 µM for TK-VI and TK-VIII, respectively. The clonogenic survival assay indicated that concentrations of 10 µM or higher completely inhibited the cell colony formation. In the comet assay, both TK-VI and TK-VIII increased the DNA damage score and the frequency of comet nuclei in all tested concentrations. In the micronucleus assay, TK-VI and TK-VIII at 10 µM increased the frequency of MN in CHO-K1 cells. Both TK-VI and TK-VIII exhibited genotoxic effects. Our findings underscore the importance of considering the genotoxicological safety of peptaibols, particularly when assessing their potential for other biological activities.

Objectives and achievements of the HUMN project on its 26th anniversary.

Micronuclei (MN) are a nuclear abnormality that occurs when chromosome fragments or whole chromosomes are not properly segregated during mitosis and consequently are excluded from the main nuclei and wrapped within nuclear membrane to form small nuclei. This maldistribution of genetic material leads to abnormal cellular genomes which may increase risk of developmental defects, cancers, and accelerated aging. Despite the potential importance of MN as biomarkers of genotoxicity, very little was known about the optimal way to measure MN in humans, the normal ranges of values of MN in healthy humans and the prospective association of MN with developmental and degenerative diseases prior to the 1980's. In the early 1980's two important methods to measure MN in humans were developed namely, the cytokinesis-block MN (CBMN) assay using peripheral blood lymphocytes and the Buccal MN assay that measures MN in epithelial cells from the oral mucosa. These discoveries greatly increased interest to use MN assays in human studies. In 1997 the Human Micronucleus (HUMN) project was founded to initiate an international collaboration to (i) harmonise and standardise the techniques used to perform the lymphocyte CBMN assay and the Buccal MN assay; (ii) establish and collate databases of MN frequency in human populations world-wide which also captured demographic, lifestyle and environmental genotoxin exposure data and (iii) use these data to identify the most important variables affecting MN frequency and to also determine whether MN predict disease risk. In this paper we briefly describe the achievements of the HUMN project during the period from the date of its foundation on 9th September 1997 until its 26th Anniversary in 2023, which included more than 200 publications and 23 workshops world-wide.

RCC1 depletion drives protein transport defects and rupture in micronuclei.

Micronuclei (MN) are a commonly used marker of chromosome instability that form when missegregated chromatin recruits its own nuclear envelope (NE) after mitosis. MN frequently rupture, which results in genome instability, upregulation of metastatic genes, and increased immune signaling. MN rupture is linked to NE defects, but the cause of these defects is poorly understood. Previous work from our lab found that chromosome identity correlates with rupture timing for small MN, i.e. MN containing a short chromosome, with more euchromatic chromosomes forming more stable MN with fewer nuclear lamina gaps. Here we demonstrate that histone methylation promotes rupture and nuclear lamina defects in small MN. This correlates with increased MN size, and we go on to find that all MN have a constitutive nuclear export defect that drives MN growth and nuclear lamina gap expansion, making the MN susceptible to rupture. We demonstrate that these export defects arise from decreased RCC1 levels in MN and that additional loss of RCC1 caused by low histone methylation in small euchromatic MN results in additional import defects that suppress nuclear lamina gaps and MN rupture. Through analysis of mutational signatures associated with early and late rupturing chromosomes in the Pan-Cancer Analysis of Whole Genomes (PCAWG) dataset, we identify an enrichment of APOBEC and DNA polymerase E hypermutation signatures in chromothripsis events on early and mid rupturing chromosomes, respectively, suggesting that MN rupture timing could determine the landscape of structural variation in chromothripsis. Our study defines a new model of MN rupture where increased MN growth, caused by defects in protein export, drives gaps in nuclear lamina organization that make the MN susceptible to membrane rupture with long-lasting effects on genome architecture.

Eco-toxicological effects assessment: comparative characteristics of environmental conditions and status of vertebrate indicator species in the "Dnepr" launch vehicle accident zone.

Space rockets are regularly launched from the Baikonur Cosmodrome in Kazakhstan. The ecological impact of territories affected by the consequences of space rocket activities on the environment is a significant concern. On July 27, 2006, the Dnepr rocket was launched from the Baikonur Cosmodrome, resulting in an abnormal situation and its emergency fall. The rocket fuel components, heptyl, and amyl, led to decontamination and reclamation activities. However, the self-restoration of soil and vegetation cover is currently in the earliest stages. Consequently, an assessment of the remote consequences of the accidental fall of the Dnepr launch vehicle for environmental objects was conducted. The study involved eco-toxicological characterization of habitat conditions, assessment of species diversity, determination of key morphophenetic indicators, and the genetic status of indicator species as the main parameters. The results revealed an increased level of genotoxicity in soils at the accident site. While there were deviations from the norm in some morphophenetic and cytogenetic parameters in indicator animals, they were not critical for their existence in this territory. Possibly, at the physiological level, they exhibit a high enough adaptation potential and compensatory mechanism.

Inheritance patterns of male asexuality in hybrid males of a water frog Pelophylax esculentus.

Gametogenesis produces gametes as a piece of genetic information transmitted to the offspring. While during sexual reproduction, progeny inherits a mix of genetic material from both parents, asexually reproducing organisms transfer a copy of maternal or paternal DNA to the progeny clonally. Parthenogenetic, gynogenetic and hybridogenetic animals have developed various mechanisms of gametogenesis, however, their inheritance is not fully understood. Here, we focused on the inheritance of asexual gametogenesis in hybrid Pelophylax esculentus (RL), emerging after crosses of P. lessonae (LL) and P. ridibundus (RR). To understand the mechanisms of gametogenesis in hybrids, we performed three-generation experiments of sexual P. ridibundus females and hybrids from all-male hybrid populations. Using fluorescent in situ hybridization, micronuclei analysis, flow cytometry and genotyping, we found that most adult hybrid males simultaneously produced two types of clonal sperm. Also, most male tadpole progeny in two successive backcrossed generations simultaneously eliminated L and R parental genomes, while some progeny produced only one type of sperm. We hypothesize that the reproductive variability of males producing two kinds of sperm is an adaptive mechanism to reproduce in mixed populations with P. ridibundus and may explain the extensive distribution of the all-male lineage across the European River Basin.

Cytome analysis (micronuclei and nuclear anomalies) in bioindication of environmental pollution in animals with nuclear erythrocytes.

Assessment of cytogenetic homeostasis of indicator animals is of great importance in ecological monitoring. The simplest method of its study is micronucleus analysis. Animals with nuclear erythrocytes are often used as indicator animals. In addition to the micronuclei usually recorded, a wide range of cytological nuclear and cellular abnormalities (cytomic analysis) is encountered when assessing the spontaneous level and under the influence of anthropogenic factors. Spontaneous frequency of cytogenetic disorders in 36 species of fish, amphibians, reptiles and birds was studied. Ecological monitoring of territories of Kazakhstan with different types of pollution (radiation, petrochemical, pesticide, heavy metals, due to rocket and space activities) was carried out with the help of separate species of animals. The results of the study include comparative descriptions, schematics and microphotographs clearly demonstrating a wide range of cytological anomalies of nuclear erythrocytes of animals of different classes. The greatest spectrum of nuclear anomalies in the studied animals was registered at petrochemical and pesticide contamination of territories. Depending on the tasks and climatic-geographical conditions, all investigated species can be used as bioindicators. Testudo horsfieldii is an exception for desert regions due to high spontaneous micronuclei level in this species. A review of the names of the main nuclear anomalies is carried out and variants of its ordering are proposed.

Polyethylene Terephthalate Microplastics Generated from Disposable Water Bottles Induce Interferon Signaling Pathways in Mouse Lung Epithelial Cells.

Microplastics (MPs) are present in ambient air in a respirable size fraction; however, their potential impact on human health via inhalation routes is not well documented. In the present study, methods for a lab-scale generation of MPs from regularly used and littered plastic articles were optimized. The toxicity of 11 different types of MPs, both commercially purchased and in-lab prepared MPs, was investigated in lung epithelial cells using cell viability, immune and inflammatory response, and genotoxicity endpoints. The underlying mechanisms were identified by microarray analysis. Although laborious, the laboratory-scale methods generated a sufficient quantity of well characterized MPs for toxicity testing. Of the 11 MPs tested, the small sized polyethylene terephthalate (PETE) MPs prepared from disposable water bottles induced the maximum toxicity. Specifically, the smaller size PETE MPs induced a robust activation of the interferon signaling pathway, implying that PETE MPs are perceived by cells by similar mechanisms as those employed to recognize pathogens. The PETE MPs of heterogenous size and shapes induced cell injury, triggering cell death, inflammatory cascade, and DNA damage, hallmark in vitro events indicative of potential in vivo tissue injury. The study establishes toxicity of specific types of plastic materials in micron and nano size.

The Fanconi anemia pathway induces chromothripsis and ecDNA-driven cancer drug resistance.

Chromothripsis describes the catastrophic shattering of mis-segregated chromosomes trapped within micronuclei. Although micronuclei accumulate DNA double-strand breaks and replication defects throughout interphase, how chromosomes undergo shattering remains unresolved. Using CRISPR-Cas9 screens, we identify a non-canonical role of the Fanconi anemia (FA) pathway as a driver of chromothripsis. Inactivation of the FA pathway suppresses chromosome shattering during mitosis without impacting interphase-associated defects within micronuclei. Mono-ubiquitination of FANCI-FANCD2 by the FA core complex promotes its mitotic engagement with under-replicated micronuclear chromosomes. The structure-selective SLX4-XPF-ERCC1 endonuclease subsequently induces large-scale nucleolytic cleavage of persistent DNA replication intermediates, which stimulates POLD3-dependent mitotic DNA synthesis to prime shattered fragments for reassembly in the ensuing cell cycle. Notably, FA-pathway-induced chromothripsis generates complex genomic rearrangements and extrachromosomal DNA that confer acquired resistance to anti-cancer therapies. Our findings demonstrate how pathological activation of a central DNA repair mechanism paradoxically triggers cancer genome evolution through chromothripsis.

Examining the interaction between pesticides and bioindicator plants: an in-depth analysis of their cytotoxicity.

Agrochemicals are substances used to prevent, destroy, or mitigate any pest. Their indiscriminate use can cause serious problems in ecosystems, contaminating surface and groundwater and affecting surrounding biota. However, in the environment, various natural processes such as biological degradation and photodegradation can mitigate their persistence and, consequently, their ecotoxicological impact. In this regard, this study aimed to obtain relevant data on the cytotoxic effects produced by pesticides on bioindicator plants. As observed in the literature review, cellular inhibition, nuclear anomalies, and micronucleus index are some of the different impacts commonly known from pesticides. These chemical substances can cause cytogenetic alterations in a plant bioassay. Plant bioindicators such as Allium cepa L, Vicia faba L, Pisum sativum L, Lactuca sativa L, and Lens culinaris Med are very important and effective experimental models for identifying the cytogenotoxicity of pesticides. These have been available for many years. However, they are still used today for their effectiveness in detecting and monitoring chemical substances such as agrochemicals.

Comparison of sensitivity between blood parameters and a genotoxic biomarker at low blood Pb levels: A population-based study.

BACKGROUND: Previous studies reported that lead (Pb) exposure induced adverse health effects at high exposure concentrations, however, there have been limited data on sensitivity comparisons among different health outcomes at low blood Pb levels. OBJECTIVES: To compare sensitivity between blood parameters and a genotoxic biomarker among workers exposed to low blood Pb levels (< 20 µg/dl), and to estimate a benchmark dose (BMD). METHODS: Pb-exposed workers were recruited from a lead-acid storage battery plant. Their blood lead levels (BLLs) were measured. Blood parameters and micronuclei (MN) frequencies were determined. Multivariate linear or Poisson regression was used to analyze relationships between blood parameters or MN frequencies with BLLs. Two BMD software were used to calculate BMD and its 95 % lower confidence limit (BMDL) for BLLs. RESULTS: The median BLL for 611 workers was 10.44 µg/dl with the 25th and 75th percentile being 7.37 and 14.62 µg/dl among all participants. There were significantly negative correlations between blood parameters and BLLs. However, MN frequencies correlated positively with BLLs (all P<0.05). Results from the two BMD software revealed that the dichotomous model was superior to the continuous model, and the BMDL for BLL derived from red blood cell (RBC) was 15.11 µg/dl, from hemoglobin (HGB) was 8.50 µg/dl, from mean corpuscular hemoglobin (MCH) was 7.87 µg/dl, from mean corpuscular hemoglobin concentration (MCHC) was 3.98 µg/dl, from mean corpuscular volume (MCV) was 11.44 µg/dl, and from hematocrit (HCT) was 6.65 µg/dl. The conservative BMDL obtained from the MN data was 7.52 µg/dl. CONCLUSION: Our study shows that low dose Pb exposure caused decrease of blood parameters and increase of MN frequencies. The genotoxic biomarker was more sensitive than most blood parameters. BMDLs for BLL derived from MN frequencies and the red blood cell indicators should be considered as new occupational exposure limits. Our results suggest that MN assay can be considered as a part of occupational health examination items.

Genotoxicity of selected cannabinoids in human lymphoblastoid TK6 cells.

Natural non-psychoactive cannabinoids such as cannabigerol (CBG), cannabidiol (CBD), cannabichromene (CBC), cannabidivarin (CBDV), and cannabinol (CBN) are increasingly consumed as constituents of dietary products because of the health benefits claims. Cannabinoids may reduce certain types of pain, nausea, and anxiety. Anti-inflammatory and even anti-carcinogenic properties have been discussed. However, there are insufficient data available regarding their potential (geno-)toxic effects. Therefore, we tested CBG, CBD, CBC, CBDV, and CBN for their genotoxic potential and effects on mitosis and cell cycle in human lymphoblastoid TK6 cells. The selected cannabinoids (except CBDV) induced increased micronuclei formation, which was reduced with the addition of a metabolic activation system (S9 mix). CBDV induced micronuclei only after metabolic activation. Mitotic disturbances were observed with all tested cannabinoids, while G1 phase accumulation of cells was observed for CBG, CBD and CBDV. The genotoxic effects occurred at about 1000-fold higher concentrations than are reported as blood levels from human consumption. However, the results clearly indicate a need for further research into the genotoxic effects of cannabinoids. The mechanism of the mitotic disturbance, the shape of the dose-response curves and the possible effects of mixtures of cannabinoids are aspects which need clarification.

R-loops and impaired autophagy trigger cGAS-dependent inflammation via micronuclei formation in Senataxin-deficient cells.

Senataxin is an evolutionarily conserved DNA/RNA helicase, whose dysfunctions are linked to neurodegeneration and cancer. A main activity of this protein is the removal of R-loops, which are nucleic acid structures capable to promote DNA damage and replication stress. Here we found that Senataxin deficiency causes the release of damaged DNA into extranuclear bodies, called micronuclei, triggering the massive recruitment of cGAS, the apical sensor of the innate immunity pathway, and the downstream stimulation of interferon genes. Such cGAS-positive micronuclei are characterized by defective membrane envelope and are particularly abundant in cycling cells lacking Senataxin, but not after exposure to a DNA breaking agent or in absence of the tumor suppressor BRCA1 protein, a partner of Senataxin in R-loop removal. Micronuclei with a discontinuous membrane are normally cleared by autophagy, a process that we show is impaired in Senataxin-deficient cells. The formation of Senataxin-dependent inflamed micronuclei is promoted by the persistence of nuclear R-loops stimulated by the DSIF transcription elongation complex and the engagement of EXO1 nuclease activity on nuclear DNA. Coherently, high levels of EXO1 result in poor prognosis in a subset of tumors lacking Senataxin expression. Hence, R-loop homeostasis impairment, together with autophagy failure and unscheduled EXO1 activity, elicits innate immune response through micronuclei formation in cells lacking Senataxin.

Hyaluronic acid impacts hematological endpoints and spleen histological features in African catfish (Clarias gariepinus).

Since its identification in the vitreous humour of the eye and laboratory biosynthesis, hyaluronic acid (HA) has been a vital component in several pharmaceutical, nutritional, medicinal, and cosmetic uses. However, little is known about its potential toxicological impacts on aquatic inhabitants. Herein, we investigated the hematological response of Clarias gariepinus to nominal doses of HA. To achieve this objective, 72 adult fish were randomly and evenly distributed into four groups: control, low-dose (0.5 mg/l HA), medium-dose (10 mg/l HA), and high-dose (100 mg/l HA) groups for two weeks each during both the exposure and recovery periods. The findings confirmed presence of anemia, neutrophilia, leucopoenia, lymphopenia, and eosinophilia at the end of exposure to HA. In addition, poikilocytosis and a variety of cytomorphological disturbances were observed. Dose-dependent histological alterations in spleen morphology were observed in the exposed groups. After HA removal from the aquarium for 2 weeks, the groups exposed to the two highest doses still exhibited a notable decline in red blood cell count, hemoglobin concentration, mean corpuscular hemoglobin concentration, and an increase in mean corpuscular volume. Additionally, there was a significant rise in neutrophils, eosinophils, cell alterations, and nuclear abnormalities percentages, along with a decrease in monocytes, coupled with a dose-dependent decrease in lymphocytes. Furthermore, only the highest dose of HA in the recovered groups continued to cause a significant increase in white blood cells. White blood cells remained lower, and the proportion of apoptotic RBCs remained higher in the high-dose group. The persistence of most of the haematological and histological disorders even after recovery period indicates a failure of physiological compensatory mechanisms to overcome the HA-associated problems or insufficient duration of recovery. Thus, these findings encourage the inclusion of this new hazardous agent in the biomonitoring program and provide a specific pattern of hematological profile in HA-challenged fish. Further experiments are highly warranted to explore other toxicological hazards of HA using dose/time window protocols.

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.

In vitro genomic damage caused by glyphosate and its metabolite AMPA.

Glyphosate is the most widely used systemic herbicide. There is ample scientific literature on the effects of this compound and its metabolite aminomethylphosphonic acid (AMPA), whereas their possible combined genotoxic action has not yet been studied. With the present study, we aimed to determine the level of genomic damage caused by glyphosate and AMPA in cultured human lymphocytes and to investigate the possible genotoxic action when both compounds were present at the same concentrations in the cultures. We used a micronuclei assay to test the genotoxicity of glyphosate and AMPA at six concentrations (0.0125, 0.025, 0.050, 0.100, 0.250, 0.500 µg/mL), which are more realistic than the highest concentrations used in previous published studies. Our data showed an increase in micronuclei frequency after treatment with both glyphosate and AMPA starting from 0.050 µg/mL up to 0.500 µg/mL. Similarly, a genomic damage was observed also in the cultures treated with the same concentrations of both compounds, except for exposure to 0.0065 and 0.0125 µg/mL. No synergistic action was observed. Finally, a significant increase in apoptotic cells was observed in cultures treated with the highest concentration of tested xenobiotics, while a significant increase in necrotic cells was observed also at the concentration of 0.250 µg/mL of both glyphosate and AMPA alone and in combination (0.125 + 0.125 µg/mL). Results of our study indicate that both glyphosate and its metabolite AMPA are able to cause genomic damage in human lymphocyte cultures, both alone and when present in equal concentrations.

Study of Radiosensitivity and Induction of Radiation Adaptive Response in Peripheral Blood Lymphocytes of Patients with Oncological Diseases Using the Micronuclear Test.

Radiosensitivity to low and medium doses of X-ray radiation and the ability to induce a radiation adaptive response (RAR) of lymphocytes during in vitro irradiation of peripheral blood of patients with cancer were studied. The criterion for cytogenetic damage was the frequency of micronuclei (MN) in cytochalasin-blocked binucleate lymphocytes in culture. It was found that the spontaneous level of cytogenetic damage in the lymphocytes of patients was 2.6 times higher than in healthy volunteers, and there was also significant interindividual variability in values compared to the control cohort. There were no differences in mean values for radiosensitivity to low and medium doses of X-ray between the study groups. There was no correlation between the spontaneous level of MN in lymphocytes and the radiosensitivity of individuals in both groups. RAR was induced with the same frequency and to the same extent in lymphocytes from both patients and healthy individuals.

Modulatory effect of the fruit rind extract of Garcinia indica Choisy against gamma radiation induced damage in human peripheral blood lymphocytes: a preliminary study.

PURPOSE: Nowadays people are exposed to radiation due to various reasons, including natural, diagnostic, occupational or accidental exposure. High level of exposure to ionizing radiation can be fatal to human body. Synthetic drugs used to prevent radiation-induced damage are toxic in nature. Recently, Herbal drugs are being screened as an alternative due to their mechanism of action. Garcinia indica (G. indica) is one of the traditional medicinal plant which contains phytochemicals having several medicinal properties. MATERIALS AND METHODS: In this study, G. indica extract was observed for its modulatory effect against 3 Gray (Gy) gamma radiation-induced damages in human peripheral blood lymphocytes. Various concentrations of G. indica extract ranging from 1 to 25 µg/mL was added to the blood post irradiation at 0 hr. Chromosomal aberration (CA) and Cytochalasin B blocked Micronuclei Cytome (CBMN) Assay were performed as per standard procedure. RESULTS: Radiomodulatory effect of Garcinia indica fruit rind extract (GIFRE) on CA and MN formation was observed in this study. Treatment of GIFRE did not affect the mitotic index. Positive inhibition percentages for dicentrics, total chromosomal aberrations and micronuclei were observed except for one instance. CONCLUSION: Owing to the various properties of Garcinia extracts, it makes it a potential candidate to be tested for its radiomodulatory effect. Based on the results observed in this preliminary study, it could act as a radiomodulatory agent. Radiomodulatory effect of GIFRE could possibly serve it as a potential herbal medicinal alternative to current drugs. However, results of this study need to be validated on larger sample size.