Search Results (16)

The quality of riverine water is largely influenced by anthropogenic activity; however, worldwide monitoring practices remain largely limited to assessing water physicochemical parameters. To evaluate the potential of river contaminants to cause biological effects, two standard tests with the Tradescantia plant were used: Trad-SHM (stamen hair mutations) and Trad-MN (appearance of micronuclei in sporogenic cells). Water samples were collected from nine localities along the two rivers of the Kura basin: before and after the towns of Spitak, Vanadzor, Tumanyan, Alaverdi, and before Akhtala. The sampling locations were impacted by different anthropogenic sources—domestic and agricultural (Spitak and Vanadzor) and domestic and mining (Tumanyan, Alaverdi, and Akhtala). The biological responses were compared to water quality monitoring data based on physicochemical parameters (ions and metals). Monitoring results indicated “good” or “average” water quality, except for the exceedance of Fe, Mn, Cu, and Pb concentrations in the mining-affected areas. However, Tradescantia showed significantly increased frequency of hair cell mutations and micronucleus formation from urban/agricultural to mining-affected samples. The multivariate PCA analysis distinguished between the samples by associating ammonium and nitrate levels with the samples from urban/agricultural areas and the concentrations of Fe, Mn, Co, and Al with the biological responses in mining-affected samples. However, most likely, toxic substances in the riverine waters acted synergistically. The results indicated that compliance with chemical standards does not necessarily equate to biological safety. They emphasize the need to incorporate biological effects into monitoring programs to improve their contribution to informed decision-making regarding environmental impacts. Full article

This study evaluates the cytotoxic and genotoxic-like potential of an ipfencarbazone-based herbicide formulation (IPF-BH; commercial product Hokuto, containing 250 g/L of the triazolinone herbicide ipfencarbazone) in human peripheral lymphocytes in vitro across a concentration range of 62.5–1000 µg/mL. Cytotoxicity was monitored via the mitotic index (MI), while cytogenetic damage was assessed using the cytokinesis-block micronucleus (MN) assay and the alkaline comet assays. Comparisons were performed using one-way ANOVA, followed by Dunnett’s post hoc test, against the negative control. Results indicated a concentration-dependent cytotoxic effect, with a marked reduction in MI observed at all tested concentrations (p < 0.001). MN frequency was significantly elevated at concentrations ≥125 µg/mL, whereas the 62.5 µg/mL concentration did not induce significant micronuclei formation. The comet assay revealed increased DNA damage parameters (tail length, tail intensity (%), and tail moment) across the tested concentration range, albeit with a non-monotonic profile for tail length and tail intensity. These findings suggest that IPF-BH exposure is associated with marked cytotoxicity and a genotoxic response in this in vitro model at concentrations within the OECD 487-acceptable cytotoxicity window, together with cytotoxicity-associated genotoxic-like effects at strongly cytotoxic concentrations in human peripheral lymphocytes under in vitro conditions. Because IPF-BH is a commercial formulation, and no direct mechanistic endpoints (e.g., reactive oxygen species, mitochondrial transmembrane potential, lipid peroxidation, glutathione) were measured, and because the present design was performed without exogenous metabolic activation (no S9 supplementation), the observed effects cannot be unambiguously attributed to ipfencarbazone alone or to a defined mechanism of action; extrapolation to in vivo genotoxicity requires complementary +S9 and rodent in vivo follow-up studies. Full article

Humans spend a substantial proportion of their time indoors, where exposure to environmental pollutants such as radon gas and particulate contaminants in household dust is common. While radon is a well-established risk factor for lung cancer, household dust may serve as a reservoir for a complex mixture of indoor and outdoor pollutants. However, the biological effects of such exposures, particularly under sequential conditions, remain incompletely understood. This study aimed to investigate the cytotoxic and genotoxic effects of sequential exposure to household dust extract followed by indoor radon using human lung adenocarcinoma (A549) cells as an in vitro model. Household dust samples from upper northern Thailand were extracted and applied to cells, followed by controlled radon exposure. Cellular responses were evaluated using cell viability assays, cytokinesis-block micronucleus (MN) formation assays, and Western blot analysis of oxidative stress-related (Nrf2/HO-1), DNA damage-related (γ-H2AX), autophagy-related (LC3), and inflammatory-related (IL-6) protein expression. Exposure to household dust extract was associated with reduced cell viability and increased MN formation, while radon exposure alone produced relatively modest effects under the present conditions. Sequential exposure to household dust extract followed by indoor radon was associated with increased oxidative stress-related responses and elevated DNA damage than either treatment alone under the present experimental conditions. A trend toward autophagy-related responses was also observed, and the overall findings may indicate possible combined biological responses under sequential exposure conditions. These findings suggest that sequential exposure may be associated with changes in oxidative stress-related pathways, DNA damage responses, and autophagy-related processes in this in vitro model. However, the results should be interpreted with caution as they are derived from a single cancer cell line and there are limitations to the in vitro exposure model. Further studies using additional cell models and in vivo systems are warranted to further clarify the potential biological and human health relevance of these findings. Full article

The fruits of Solanum lycopersicum L. cultivar “Microtom” are a powerful source of antioxidants. We investigated whether two light-quality regimes, i.e., fluorescent white (FL) and red-blue (RB), influenced the antioxidant composition in such fruits, and assessed the potential radioprotective properties of their extracts on normal human cells exposed to clinical photons as used in cancer radiotherapy (RT). Increasing normal-tissue tolerance to radiation is critical for reducing the risk of RT-associated sequelae. Biochemical characterization showed that RB enhanced the content of antioxidant phytochemicals (i.e., polyphenols, flavonoids, total carotenoids, lycopene), while FL promoted ascorbic acid synthesis. Initially tested at 200 µg/mL, RB-derived extracts decreased radiation-induced DNA damage as measured by the cytokinesis-block micronucleus (CBMN) assay in epidermal HaCaT cells. Both RB and FL regimes were subsequently studied in MCF-10A breast cancer (BC) cells, a model of normal-tissue radioresponse in BC RT, using extracts at 100 and 200 µg/mL and also evaluating oxidative stress by a ROS detection assay. Both FL and RB afforded radioprotection. However, RB suppressed radiation-induced MN formation and oxidative stress to a greater extent compared to FL. Therefore, modulation of light-quality regimes represents an innovative approach for developing radionutraceuticals with potential benefits for RT patients. Full article

Birds have played a crucial role as environmental monitors throughout history, ranging from the use of canaries to detect methane and carbon monoxide in mines to the decline of raptors and seabirds during the DDT era due to widespread organochlorine pesticide contamination. Owing to their high diversity and capacity for bioaccumulation, birds are widely recognized as effective indicators of environmental change and pollutant exposure. Cytogenetic techniques have been increasingly applied over the past two decades to assess micronuclei formation resulting from interactions with clastogenic and aneugenic chemical compounds. The main goals of this study were (a) to evaluate a subset of the bird community in the southeastern Brazilian Cerrado as potential environmental indicators of pesticide exposure using the erythrocyte micronucleus test and (b) to investigate possible associations between bird morphometric traits and micronuclei frequency. Birds were sampled from three groups of coffee farms in the Brazilian Cerrado. Blood samples were collected from 152 individuals (122 on farms and 30 at the reference site) via the metatarsal vein, followed by slide preparation for micronucleus analysis. Two slides were prepared per bird; each slide was scored for 10,000 erythrocytes, and MN frequency was reported as the mean across slides. The species Leptotila rufaxilla, Volatinia jacarina, Galbula ruficauda, Gnorimopsar chopi, Molothrus bonariensis, Passer domesticus, Turdus leucomelas, and Turdus rufiventris exhibited six or more micronuclei per 10,000 erythrocytes, indicating the highest potential as bioindicators of environmental contamination. Micronuclei frequency in erythrocytes was positively correlated with the use of mixed pesticides, with variation depending on the size of the coffee farms. Although a slight negative biological trend was observed between micronuclei frequency and certain morphometric traits, particularly bill length, no statistically significant correlations were found. Similarly, birds from large farms exhibited a slight reduction in certain morphometric features, though these differences were also not statistically significant. These results highlight the utility of selected bird species as early-warning bioindicators for pesticide exposure in tropical agroecosystems. Full article

Triadimenol is a systemic fungicide widely used in agriculture to manage plant diseases, especially fungal infections. This study aims to evaluate the short-term (24, 48, 72 and 96 h) and long-term (10, 20, and 30 days) genotoxic effects of different concentrations of triadimenol on zebrafish (Danio rerio) erythrocytes using micronucleus (MN) and erythrocyte nuclear abnormal (ENA) assay. Fish were treated with 1.5, 3, and 6 mg/L concentrations of triadimenol for short and long-term periods. After the treatment period, blood was collected with heparin syringe, smears were prepared, the preparations were fixed and stained. For MN assay in short-term treatments, statistically significant MN formation was found at all concentrations of triadimenol for 24 h treatment, at the highest triadimenol concentration for 48 h, at 1.5 and 3 mg/L concentrations for 72 h, and at 3 mg/L concentrations for 96 h, compared to the negative control. In long-term treatments, significant increases in MN formation were observed at all concentrations of triadimenol for 10 and 20 days of treatment compared to the negative control. Mortality occurred at 3 and 6 mg/L concentrations in the 30-day treatment. The most frequently detected abnormalities included echinocytes and binuclear cells. For ENA assay, abnormalities such as echinocytes, binuclear cells, segmented cells, and kidney-shaped nuclei were detected in fish erythrocytes treated with different concentrations of triadimenol. All concentrations of triadimenol caused an increase in the total abnormality level in Danio rerio erythrocytes at all treatment times. These increases were concentration dependent for both short-term and long-term treatments. In conclusion, this study emphasized the potential genotoxic risks of triadimenol fungicide for aquatic organisms in both short-term and long-term treatments and the need for further ecotoxicological evaluation. Full article

Environmental exposure to microplastics (MPs) and nanoplastics (NPs) is an increasing concern from human health perspectives. Little information on the genotoxic and cytotoxic potential of NP particles in human cells is available. We aimed to assess the cytotoxic and genotoxic potential of polystyrene nanoplastics (PSNPs) at different concentrations (2000μg/mL, 1000μg/mL, and 500μg/mL) by using chromosomal aberration (CA) and cytokinesis-block micronucleus assays (CBMN) on human peripheral lymphocytes. Dose-dependent hemolytic activity and cell viability were observed against the PSNPs exposure. Increased chromosomal aberrations, such as chromosomal breaks and dicentric chromosomes, and an increase in nucleoplasmic bridge (NBP) formation and nuclear budding (NBUD) were observed. The frequency of mitotic index (MI) decreased significantly in the PSNP-exposed groups from lower to higher concentrations. A significant increase in micronuclei (MN) formation and cytostasis% and a dose-dependent reduction in nuclear division index (NDI) in PSNP-exposed groups indicated oxidative stress-mediated cytotoxicity, DNA damage, and genomic instabilities due to PSNP exposure in human lymphocyte cells. This study highlights the importance of understanding the toxic mechanisms and associated chronic and acute health effects on humans due to exposure to this pervasive environmental pollutant. Full article

Indiscriminate use of pesticides in agriculture has many negative implications on both abiotic and biotic components of the environment [¹]. One of the alternative methods to maintaining productivity and quality of life is using compounds produced by the secondary metabolism of plants, such as essential oils [²]. Due to their rapid efficacy and degradability, essential oils are used as bioherbicides, biostimulants, anti-microbial agents, insect repellents, etc. Evaluations of essential oils toxic, cytotoxic, and genotoxic potentials employing ecotoxicological bioassays are of great importance in determining possible risks [³]. To determine genotoxicity and clastogenic effects of various factors, mitotic divisions are used, with the evaluated parameters being the mitotic index (MI) and the frequency of micronuclei [⁴]. This study aims to analyze the potential phytotoxic effect of thyme essential oil given its potential use as a plant biostimulant. This phytotoxic assay was done by investigating the clastogenic effect on Vicia faba root meristems. After sterilization, seeds were left to hydrate for 24 h in sterile water. Sterile deionized water was used for the control variant and thyme essential oil at a 0.1% concentration for the sample. The seed plates were placed at 23 °C under dark conditions until the length of rootlets reached 2–3 cm. For cytological analysis of the mitotic index (MI) and micronucleus (MN) tests, 1–2 cm of rootlets were subjected to Carnoy fixation solution for 24 h. The samples were then rinsed with distilled water and hydrolyzed with 1N HCl at 60 °C for 6 min. Schiff’s reagent was used for staining. The mitotic index was calculated as the number of cells in mitosis divided by the total number of cells, x 100, per 1000 scored cells/sample resulting from 10 separate roots for each group. The mitotic index of Vicia faba in the 0.1% essential oil sample did not show significant differences compared to the control sample. The mean values of MI were 31.4% for the control and 31.2% for the sample with thyme essential oil, indicating a similar cell division ratio. Additionally, this essential oil concentration did not significantly lead to micronuclei formation at root meristems relative to the control. Various types of physiological (C-metaphase, stickiness, bridge, laggard, etc.) and clastogenic chromosomal aberrations (chromosomal breaks, fragments, etc.) were not observed when analyzing the cell division phases. Following the study performed on Vicia faba, it was noted that 0.1% thyme essential oil has no cytotoxic effect, as no chromosomal aberrations were observed in the samples, and it did not induce the inhibition of cell proliferation in root meristems. The relative frequencies of the various mitotic phases were not affected by thyme essential oil. Full article

Considering that electronic wastes (e-wastes) have been recently recognized as a potent environmental and human threat, the present study aimed to assess the potential risk of personal computer motherboards (PCMBs) leaching into aquatic media, following a real-life scenario. Specifically, PCMBs were submerged for 30 days in both distilled water (DW) and artificial seawater (ASW). Afterwards, PCMBs leachates were chemically characterized (i.e., total organic carbon, ions, and trace elements) and finally used (a) for culturing freshwater (Chlorococcum sp. and Scenedesmus rubescens) and saltwater (Dunaliella tertiolecta and Tisochrysis lutea) microalgae for 10 days (240 h), (b) as the exposure medium for mussel Mytilus galloprovincialis (96 h exposure), and (c) for performing the Cytokinesis Block Micronucleus (CBMN) assay in human lymphocytes cultures. According to the results, PCMBs could mediate both fresh- and marine algae growth rates over time, thus enhancing the cytotoxic, oxidative, and genotoxic effects in the hemocytes of mussels (in terms of lysosomal membrane impairment, lipid peroxidation, and NO content and micronuclei formation, respectively), as well as human lymphocytes (in terms of MN formation and CBPI values, respectively). The current findings clearly revealed that PCMBs leaching into the aquatic media could pose detrimental effects on both aquatic organisms and human cells. Full article

Cylindrospermopsin (CYN) and microcystins (MC) are cyanotoxins that can occur simultaneously in contaminated water and food. CYN/MC-LR mixtures previously investigated in vitro showed an induction of micronucleus (MN) formation only in the presence of the metabolic fraction S9. When this is the case, the European Food Safety Authority recommends a follow up to in vivo testing. Thus, rats were orally exposed to 7.5 + 75, 23.7 + 237, and 75 + 750 μg CYN/MC-LR/kg body weight (b.w.). The MN test in bone marrow was performed, and the standard and modified comet assays were carried out to measure DNA strand breaks or oxidative DNA damage in stomach, liver, and blood cells. The results revealed an increase in MN formation in bone marrow, at all the assayed doses. However, no DNA strand breaks nor oxidative DNA damage were induced, as shown in the comet assays. The histopathological study indicated alterations only in the highest dose group. Liver was the target organ showing fatty degeneration and necrotic hepatocytes in centrilobular areas, as well as a light mononuclear inflammatory periportal infiltrate. Additionally, the stomach had flaking epithelium and mild necrosis of epithelial cells. Therefore, the combined exposure to cyanotoxins may induce genotoxic and histopathological damage in vivo. Full article

During almost 40 years of use, the micronucleus assay (MN) has become one of the most popular methods to assess genotoxicity of different chemical and physical factors, including ionizing radiation-induced DNA damage. In this minireview, we focus on the position of MN among the other genotoxicity tests, its usefulness in different applications and visibility by international organizations, such as International Atomic Energy Agency, Organization for Economic Co-operation and Development and International Organization for Standardization. In addition, the mechanism of micronuclei formation is discussed. Finally, foreseen directions of the MN development are pointed, such as automation, buccal cells MN and chromothripsis phenomenon. Full article

Rhaphidophora pinnata is suggested to prevent or treat cancer of genetic mutations. In this study, antimutagenic activity of an ethanol extract of Rhaphidophora pinnata leaves was evaluated by using a bone marrow micronucleus assay on mice. Male mice (20–30 g) were treated for sevendays with an ethanol extract of Rhaphidophora pinnata leaves at a dose of 500, 750 and 1000 mg/kg/day/orally, prior to exposure to cyclophosphamide (i.p. 30 mg/kg), 24 h after the end of the treatment. Antimutagenic activity was determined by the decrease of micronuclei (MN). The results showed that a single administration of all variant doses of the extract had significantly decreased the micronucleus formation in bone marrow cell of mice as compared to the cyclophosphamide group. The ethanol extract of Rhaphidophora pinnata leaves had antimutagenic activity against cyclophosphamide-induced gene mutation. Full article

Background: To investigate the effects of S-phase kinase protein 2 (SKP2) expression on the radiation induced bystander effect (RIBE) in esophageal cancer (EC) cells. Materials and Methods: Western blot was used to detect the levels of SKP2, Rad51, and Ku70 in EC cells. Positive transfection, RNAi, micronucleus (MN), and γ-H2AX focus formation assay were used to investigate the effects of SKP2 on RIBE induced by irradiated cells. Results: We found a significant negative correlation between SKP2 expression and MN frequency (p < 0.05) induced by RIBE. The results were further confirmed by positive transfection, RNAi, and rescue experiments.γ-H2AX focus formation assay results indicated that overexpression of SKP2 in the irradiated cells inhibited the DNA damage of RIBE cells. However, when SKP2 expression decreased in irradiated cells, the DNA damage of RIBE cells increased. Increased or decreased expression levels of SKP2 had effects on Rad51 expression under the conditions of RIBE. Conclusions: These results showed, for the first time, that SKP2 expression can inhibit RIBE of EC cells. The mechanism may function, at least partly, through the regulation of Rad51 in the ability to repair DNA damage. Full article

During radiotherapy procedures, radiation-induced bystander effect (RIBE) can potentially lead to genetic hazards to normal tissues surrounding the targeted regions. Previous studies showed that RIBE intensities in cell cluster models were much higher than those in monolayer cultured cell models. On the other hand, low-concentration carbon monoxide (CO) was previously shown to exert biological functions via binding to the heme domain of proteins and then modulating various signaling pathways. In relation, our previous studies showed that exogenous CO generated by the CO releasing molecule, tricarbonyldichlororuthenium (CORM-2), at a relatively low concentration (20 µM), effectively attenuated the formation of RIBE-induced DNA double-strand breaks (DSB) and micronucleus (MN). In the present work, we further investigated the capability of a low concentration of exogenous CO (CORM-2) of attenuating or inhibiting RIBE in a mixed-cell cluster model. Our results showed that CO (CORM-2) with a low concentration of 30 µM could effectively suppress RIBE-induced DSB (p53 binding protein 1, p53BP1), MN formation and cell proliferation in bystander cells but not irradiated cells via modulating the inducible nitric oxide synthase (iNOS) andcyclooxygenase-2 (COX-2). The results can help mitigate RIBE-induced hazards during radiotherapy procedures. Full article

To investigate the cellular effects of terahertz (THz) exposure, human corneal epithelial (HCE-T) cells derived from human eye were exposed to 0.12 THz radiation at 5 mW/cm² for 24 h, then the genotoxicity, morphological changes, and heat shock protein (Hsp) expression of the cells were examined. There was no statistically significant increase in the micronucleus (MN) frequency of cells exposed to 0.12 THz radiation compared with sham-exposed controls and incubator controls, whereas the MN frequency of cells treated with bleomycin for 1 h (positive control) did increase significantly. Similarly, there were no significant morphological changes in cells exposed to 0.12 THz radiation compared to sham-exposed controls and incubator controls, and Hsp expression (Hsp27, Hsp70, and Hsp90α) was also not significantly different between the three treatments. These results indicate that exposure to 0.12 THz radiation using the present conditions appears to have no or very little effect on MN formation, morphological changes, and Hsp expression in cells derived from human eye. Full article