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Abstract Background The use of organotypic human tissue models in genotoxicity has increased as an alternative to animal testing. Genotoxicity is generally examined using a battery of in vitro assays such as Ames and micronucleus (MN) tests that cover gene mutations and structural and numerical chromosome aberrations. At the 7th International Workshop on Genotoxicity Testing, working group members agreed that the skin models have reached an advanced stage of maturity, while further efforts in liver and airway models are needed [Pfuhler et al., Mutat. Res. 850–851 (2020) 503135]. Organotypic human airway model is composed of fully differentiated and functional respiratory epithelium. However, because cell proliferation in organotypic airway models is thought to be less active, assessing their MN-inducing potential is an issue, even in the cytokinesis-blocking approach using cytochalasin B (CB) [Wang et al., Environ. Mol. Mutagen. 62 (2021) 306–318]. Here, we developed a MN test using EpiAirway™ in which epidermal growth factor (EGF) was included as a stimulant of cell division. Results By incubating EpiAirway™ tissue with medium containing various concentrations of CB, we found that the percentage of binucleated cells (%BNCs) almost plateaued at 3 μg/mL CB for 72 h incubation. Additionally, we confirmed that EGF stimulation with CB incubation produced an additional increase in %BNCs with a peak at 5 ng/mL EGF. Transepithelial electrical resistance measurement and tissue histology revealed that CB incubation caused the reduced barrier integrity and cyst formation in EpiAirway™. Adenylate kinase assay confirmed that the cytotoxicity increased with each day of culture in the CB incubation period with EGF stimulation. These results indicated that chemical treatment should be conducted prior to CB incubation. Under these experimental conditions, it was confirmed that the frequency of micronucleated cells was dose-dependently increased by apical applications of two clastogens, mitomycin C and methyl methanesulfonate, and an aneugen, colchicine, at the subcytotoxic concentrations assessed in %BNCs. Conclusions Well-studied genotoxicants demonstrated capability in an organotypic human airway model as a MN test system. For further utilization, investigations of aerosol exposure, repeating exposure protocol, and metabolic activation are required.

Abstract Background Genotoxicity in tissues other than hematopoietic tissues, such as the liver and gastrointestinal (GI) tract, is an important focus in the risk assessment of chemicals in humans. We previously developed a rat micronucleus test for the GI tract, which is the first contact tissue where chemicals are introduced into the body through oral exposure. Target cells were obtained from fresh tissue samples by ethylenediaminetetraacetic acid disodium salt (EDTA) treatment. As an improvement to this method, we have used formalin-fixed tissues instead of fresh tissues; this approach can be used for tissues that are sampled from other toxicological tests and that are archived for several years. This new method can be used for examining micronucleus induction retrospectively when needed. In the present study, we compared the performance of the EDTA method and the new method with formalin-fixed tissues (formalin-fixation method). Results Histological examination showed that both the EDTA and formalin-fixation methods could be used for collecting cells located in or above the proliferative zone of the GI tract tissues of rats. In addition, the collected cells were similar in shape. We conducted micronucleus tests with rat GI tract tissues by the two methods using model chemicals, which were used as positive control chemicals (a combination of diethylnitrosamine, 1,2-dimethylhydrazine dihydrochloride, and potassium bromate). The two methods showed similar results. We additionally evaluated the aging effect of tissues stored in formalin fixative. The results showed that 1 year of storage did not affect the frequency of micronucleated cells. Conclusion The equivalence of the EDTA and formalin-fixation methods was confirmed, and micronucleus analysis was possible up to at least 1 year after formalin fixation of the GI tract, indicating that the formalin-fixation method is valuable for the rat GI tract micronucleus test.

Background Chloramine-T (CL-T) is a synthetic sodium salt used as a disinfectant in fish farms to combat bacterial infections in fish gills and skin. While its efficacy in pathogen control is well-established, its reactivity with various functional groups has raised concerns. However, limited research exists on the toxicity of disinfection by-products to aquatic organisms. Therefore, this study aims to assess the sublethal effects of CL-T on adult zebrafish by examining biomarkers of nucleus cytotoxicity and genotoxicity, acetylcholinesterase (AChE) inhibition, and histopathological changes. Methods Male and female adult zebrafish (wildtype AB lineage) specimens were exposed to 70, 140, and 200 mg/L of CL-T and evaluated after 96 h. Cytotoxic and genotoxic effects were evaluated by estimating the frequencies of nuclear abnormalities (NA), micronuclei (MN), and integrated optical density (IOD) of nuclear erythrocytes. Histopathological changes in the gills and liver were assessed using the degree of tissue changes (DTC). AChE activity was measured in brain samples. Results and conclusions At a concentration of 200 mg/L, NA increased, indicating the cytogenotoxic potential of CL-T in adult zebrafish. Morphological alterations in the nuclei were observed at both 70 and 200 mg/L concentrations. Distinct IOD profiles were identified across the three concentrations. There were no changes in AChE activity in adult zebrafish. The DTC scores were high in all concentrations, and histological alterations suggested low to moderate toxicity of CL-T for adult zebrafish.

Cytogenetic studies of Pinus sylvestris seed progeny have been carried out for the first time in the Murmansk region of Russia. Seeds were collected in the territory of 6 district forestries: Zelenoborsky, Kovdorsky, Kandalakshsky, Zasheikovsky, Umbsky and Nickelsky, which were at different distances from large copper-nickel plants. Analysis revealed higher S, Cu, and Ni content in Pinus sylvestris tree seeds from the Zasheikovsky and Nickelsky district forestries. Seeds from the Zelenoborsky district forestry had a higher Cu content (13.6 ± 0.5 mg/kg) compared to other areas. It was found that the frequency of mitotic pathologies in all areas of the study exceeded the level of spontaneous mutation in 5%. The most frequent aberrant cells were registered in the root meristem of seedlings from the Zasheikovsky district forestry, and their proportion averaged 9.4 ± 1.3% of the total number of cells studied at the metaphase and ana-telophase of mitosis stages. In Pinus sylvestris seedlings, micronuclei were noted in the cells at the interphase stage, often varying on average from 0.2 ± 0.1% in plants from the Kandalakshsky district forestry to 0.9 ± 0.3% from the Zasheikovsky district forestry. The data obtained testify to the colossal impact of heavy metals on the living organism cell genetic apparatus. The negative effect from industries, as sources of air pollutants, extends over tens of kilometers. Therefore, regularly monitoring the cytogenetic parameters of bioindicators such as Pinus sylvestris is necessary. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Industrial Hygiene & Toxicology / Arhiv za Higijenu Rada I Toksikologiju is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pollution generated by the mining industry can cause harm to wildlife. This study aimed to evaluate the cytotoxicity, genotoxicity and mutagenicity in bats environmentally exposed to open pit mining. Thus, 62 bats of the following species, Carollia perspicillata, Glossophaga soricina, Phyllostomus hastatus, and Desmodus rotundus exposed to mining activities (ferronickel) were used in the analysis. The animals were obtained in samplings in July and November of 2021, totaling 8 days of sampling in the field. The results indicated that species differ in the frequency of genotoxic damage between sampling points within the mining landscape. Cytotoxicity was observed by scoring of karyorrhexis, pyknosis and karyolysis. The most captured species, C. perspicillata, showed differences in DNA damage between exposed and unexposed populations, but no differences were observed between males (n = 14) and females (n = 20). G. soricina was also a sensitive species for indicating a high frequency of DNA damages compared to the omnivore P. hastatus. Elements such as Mn, Cr, Pb, and Zn observed in water samples were at high levels in the mining area. We conclude that bats in mining areas are susceptible to increased DNA damage as already identified for other species. [ABSTRACT FROM AUTHOR]

Since, fish is a significant native species of the aquatic environment and are exposed to multiple pollution states, they are used as models for ecotoxicological investigations of aquatic contaminants, particularly metal toxicity. We investigated genotoxicity induced in whole blood and gill tissues through comet assay and micronucleus (MN) test in Labeo rohita after 96-hour in vivo static exposure to copper oxide nanomaterials at three sublethal (SL) test concentrations, including sublethal concentration I (SL-I; 1/4th of LC50 = 29.5 µg/liter), sublethal concentration II (SL-II; 1/2nd of LC 50 = 59 µg/liter) and sublethal concentration III (SL-III; 3/4th of LC50 = 88.5 µg/liter), along with a control. The 96-hour LC50 value for copper oxide nanomaterials was estimated to be 118.7 µg/L in a static system in the test species. Tissue samples were collected at 24, 48, 72 and 96 hours postexposure. Results indicated the mean percent DNA damage in the comet tail and MN induction in gills and whole blood showed a concentration-dependent increase up to 96-hour exposure. The results of this investigation will be useful in determining the organ-specific risk of CuO-NM-induced genotoxicity in fish. [ABSTRACT FROM AUTHOR]

Background/Aim: Exposure to chromium (VI) [Cr(VI)] has been postulated to be associated with the induction of cancer. In vivo studies utilizing biomarkers of genotoxic damage could aid in elucidating the mechanisms underlying the genotoxic effects of Cr(VI) and their relationship with carcinogenesis. In this study, the origin (clastogenic and/or aneugenic damage) and kinetics of micronuclei (MN) induced by Cr(VI) were investigated. Materials and Methods: Hsd:ICR female mice were divided into groups of five individuals each. MN kinetics were measured in groups treated with 20 or 25 mg/kg CrO3 intraperitoneally using acridine orange-coated slides in peripheral blood obtained from the caudal vein 0, 12, 24, 36, 48, 60, and 72 h after treatment. Whereas identification of MN with centromeric DNA (MNK+) was measured at the dose of 20 mg/kg of CrO3, using fluorescence in situ hybridization (FISH) with a centromere-specific probe in peripheral blood obtained at 0, 12, and 48 h after treatment. Control groups were administered vehicle only. Results: Total MN were quantified and the clastogenic/aneugenic effects of Cr(VI) were evaluated based on the proportion of MNK+ versus micronuclei without centromeric DNA (MNK-). There was a significant increase in MN frequencies beginning at 12 h in the Cr(VI)-treated groups demonstrating its genotoxicity. When calculating the MNK+ as a percentage of the total MN, the increase was significant beginning 12 h after treatment. Conclusion: The fact that the MNK+ and MNK-were observed at both evaluation times corroborates Cr(VI) as a genotoxic agent and demonstrates that both clastogenic and aneugenic damages are involved in the formation of MN. [ABSTRACT FROM AUTHOR]

To evaluate the risks of hair dye exposure, we investigated cellular and molecular effects of Arianor Ebony dye, which is a mixture of azo and anthraquinone dyes, used in the composition of the black color. Cytotoxicity, genotoxicity, and gene expression of relevant molecules of apoptotic and oxidative stress mechanisms were investigated in HepG2 cells exposed to Arianor Ebony. Results showed that the dye did not induce cytotoxicity to exposed cells at a concentration up to 50 µg/mL compared to the negative control. However, genotoxic assays indicated that the dye was able to damage the genetic material at a concentration of 25 µg/mL, with induction factor values of exposed cells two- to five-fold higher than those recorded for the negative control. Moreover, the lowest observed effect concentration was 12.5 µg/mL. For gene expression, relevant changes were observed in cytochrome c and caspase 9, which decreased in cells incubated with the dye in a dose-dependent manner when compared with the negative control. In parallel, the expression of genes for antioxidant enzymes was increased in exposed cells, suggesting the presence of metabolic routes that protect cells against the toxic effect of the dye, avoiding exacerbated cellular death. Results suggested that the dye disrupted cellular homeostasis through mitochondrial dysfunction, which may be hazardous to human health. Thus, further investigations are necessary to deeply understand the mechanisms of action of the dye, considering its toxic potential found in our ex vivo assays.

Mesenchymal stromal/stem cells stem (MSC) have been widely studied due to their great potential for application in tissue engineering and regenerative and translational medicine. In MSC-based therapy for human diseases, cell proliferation is required to obtain a large and adequate number of cells to ensure therapeutic efficacy. During in vitro culture, cells are under an artificial environment and manipulative stress that can affect genetic stability. Several regulatory agencies have established guidelines to ensure greater safety in cell-based regenerative and translational medicine, but there is no specific definition about the maximum number of passages that ensure the lowest possible risk in MSC-based regenerative medicine. In this context, the aim of this study was to analyze DNA damage and chromosome alterations in adipose-derived mesenchymal stromal cells (ADMSC) until the eleventh passage and to provide additional subsidies to regulatory agencies related to number of passages in these cells. Thus, two methods in genetic toxicology were adopted: comet assay and micronucleus test. The comet assay results showed an increase in DNA damage from the fifth passage onwards. The micronucleus test showed a statistically significant increase of micronucleus from the seventh passage onwards, indicating a possible mutagenic effect associated with the increase in the number of passages. Based on these results, it is important to emphasize the need to assess genetic toxicology and inclusion of new guidelines by regulatory agencies to guarantee the safety of MSC-based therapies for human diseases.

Plants with medicinal potential may also produce adverse effects in humans. This seems to be the case for the species Rubus rosifolius, where preliminary studies demonstrated genotoxic effects attributed to extracts obtained from leaves and stems of this plant using on HepG2/C3A human hepatoma cells as a model. Considering the beneficial properties of this plant as an antidiarrheal, analgesic, antimicrobial, and antihypertensive and its effects in the treatment of gastrointestinal diseases, the present study was developed with the aim of determining the cytotoxic and genotoxic potential of extracts of leaves and stems of R. rosifolius in primary without metabolic competence in human peripheral blood mononuclear cells (PBMC). Cell viability analyses at concentrations of between 0.01 and 100 µg/ml of both extracts did not markedly affect cell viability. In contrast, assessment of the genotoxic potential using the comet assay demonstrated significant damage to DNA within PBMC from a concentration of 10 µg/ml in the stem extract, and a clastogenic/aneugenic response without cytokinesis-block proliferation index (CBPI) alterations at concentrations of 10, 20, or 100 µg/ml for both extracts. Under our experimental conditions, the data obtained demonstrated genotoxic and mutagenic effects attributed to extracts from leaves and stems of R. rosifolius in cells in the absence of hepatic metabolism. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Safety concerns about medical devices playing important role in health sciences and bioengineering research are rising day by day. Although there are specific standards regarding disposable medical materials, the information is updating with the toxicological studies. In this study, cytotoxic/genotoxic effects of chemicals leaking from serum infusion sets that have an important place in the clinic were investigated. Media containing leakage chemicals were prepared from equal samples taken from the plastic line sections of 13 different brands of serum infusion sets containing phthalates and the effects on the cultured cells were compared with the untreated control groups. To obtain leaking chemicals, extracting period was selected as 72 h, a routine set-change time in the clinic as indicated in various publications. Neutral red uptake and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tests were performed in L929 cells to determine cytotoxicity, and cytokinesis blocked micronucleus technique was performed in lymphocytes to determine genotoxicity. Cytotoxic and genotoxic damage levels were compared by evaluating cell-viability rates relative to control, micronucleus frequency, and nuclear division index values. The results showed that all sets caused a decrease in cell viability revealing the effects both on lysosomal and mitochondrial activity and increase in micronucleus frequencies in general. The number of similar studies is extremely limited, and in this study in addition to the short-term effects of using the serum infusion sets, the information about the sample tests to determine the biosecurity of disposable medical materials is given. [ABSTRACT FROM AUTHOR]

Objectives 1-Methylnaphthalene (1-MN) is composed of 2 benzene rings and belongs to polycyclic aromatic hydrocarbons. The metabolism of 1-MN in laboratory animals and bacteria leads to the formation of 1-naphthoic acid (1-NA). Material and Methods In this study the distribution of 1-NA in lung, liver, spleen, kidney and urinary excretion of 1-NA in rats after single and repeated inhalation exposure to 1-MN vapors were investigated. The activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and cytochrome were measured of the rats. Genotoxic effects were evaluated with the in vitro micronucleus test on V79 hamster fibroblasts. Results The concentrations of 1-NA in the tissues of rats after single and repeated exposure to 1-MN were dependent on the exposure dose. High levels of 1-NA were found in kidneys of animals after the single and repeated exposure to 1-MN. With an increase of 1-MN dose, an increase in the activity of cytochrome P450 (CYP1A1 and CYP1A2) was observed in the liver of rats. Compared to control animals, significantly higher ALT activity was noted in serum of rats exposed to 1-MN. The micronuclei frequency in V79 cells exposed to 1-MN (in the range of analyzable concentrations; i.e., 5–25 μg/ml) did not differ significantly from the vehicle control, whereas urine extracts from rats exposed to 1-MN induced a significant increase in the frequency of micronuclei compared to urine extracts from the group of control animals. Conclusions Metabolism of 1-MN in rats after the inhalation exposure leading to 1-NA was mainly observed during the first day after the end of exposure. It is likely that 1-MN metabolites present in rat urine can induce the increased micronuclei frequency as was shown in V79 cells. Int J Occup Med Environ Health. 2022;35(6):731–46

Pesticides are applied to plants all over the world to boost food production and lower the spread of diseases carried by insects. Exposure to the pesticides may cause genotoxic effects on target and non-target organisms, including humans. In agriculture, acetamiprid (ACE), a neonicotinoid insecticide, is frequently applied either alone or in conjunction with other pesticides. A combined approach employing the micronucleus test (MNT) and chromosomal aberrations (CAs) assay was used to evaluate the genotoxic effects of acetamiprid in the bone marrow of male Swiss albino mice. Acetamiprid was administered i.p. daily at 4.6 and 2.3 mg/kg/day along with 3% gum acacia as a negative control for 30 days. ACE treatment resulted in a small dose dependent increase in the frequencies of micronuclei per cell (0.28 ± 0.04, 0.38 ± 0.03, and 0.45 ± 0.02 for the control, 2.3 and 4.6 mg/kg b.wt. groups, respectively) and chromosomal aberrations (3.67 ± 0.61, 5.00 ± 0.45, and 7.00 ± 1.43 for the control, 2.3 and 4.6 mg/kg b.wt. groups, respectively) in bone marrow cells, but no significant differences were observed between these data sets. In conclusion, daily i.p. exposure of ACE @ 2.3 and 4.6 mg/kg b.wt. for 30 days did not produce significant genotoxic effects in the somatic cells of Swiss albino male mice. [ABSTRACT FROM AUTHOR]

Cadmium sulfide quantum dots (CdS QDs) are being developed for sensors, fluorescent probes, and other platforms and are attracting increasing attention. Given the growing demand for QDs, it is clear that there is a need to understand their potential toxicity to organisms. However, little is known regarding the genotoxicity of CdS QDs to humans. Therefore, this study used CdS QDs as the research object, cultured human peripheral blood lymphocytes, and randomly divided them into a control group, CdS I group (CdS QDs), and CdS II group (CdS QDs coated with thioglycolic acid). After cultivation, we measured the olive tail distance, tail length, tail DNA%, lymphocyte micronucleus rate, and aneuploid rate. The comet test results indicated that the indices of the QD group were significantly larger than those of the control group (P < 0.05). The results of the micronucleus and chromosome aberration tests showed that the lymphocyte micronucleus rate and chromosome aneuploid rate in the QD group were significantly increased (P < 0.05) compared with those in the control group. In conclusion, CdS QDs have certain genotoxicity to human peripheral blood lymphocytes, and the DNA damage caused by CdS QDs encapsulated with thioglycolic acid is less severe than that caused by nonencapsulated CdS QDs.

Abstract Background We previously developed a rodent gastrointestinal (GI) tract micronucleus (MN) test using the glandular stomach and/or colon, and evaluated this test method using several genotoxic carcinogens (clastogens) and genotoxic non-carcinogens; we demonstrated that this test method could detect genotoxic stomach and/or colon carcinogens with target organ specificity. In the present study, we further evaluated the sensitivity and specificity of the MN test for the rat glandular stomach and colon using three aneugens (colchicine, vinblastine sulfate, and docetaxel hydrate) and two non-genotoxic non-carcinogens (sodium chloride and sucrose). Results Male Crl:CD (SD) rats were administered test compounds through clinical administration route (orally or intravenously) for four consecutive days and then examined for the micronucleated cell frequencies in the glandular stomach and colon. We observed that all three aneugens significantly and dose-dependently increased the micronucleated cell frequencies in the stomach and colon. In contrast, neither of the two non-genotoxic non-carcinogens increased the micronucleated cell frequency in these tissues. Notably, an increase in cell proliferation was observed in the glandular stomach of rats administered a stomach toxicant, sodium chloride, but this increase did not affect the induction of micronuclei in the gastric cells. Conclusions In the present study, it was demonstrated that the glandular stomach and colon MN tests could detect aneugens as positive and could adequately evaluate non-genotoxic non-carcinogens as negative, including a chemical that enhances cell proliferation. These results provide important evidence supporting good performance of the rat glandular stomach and colon MN tests with a 4-day treatment regimen.

3‐(3,4‐Dihydroxyphenyl)‐7,8‐dihydroxycoumarin is a newly synthesized coumarin derivative with a potent antioxidant effect. The aim of the present study is to investigate the safety of this compound, determining the in vitro cytotoxic and genotoxic in human peripheral blood mononuclear cells (PBMC) and in HepG2/C3A cells. Cell viability has been investigated by the trypan blue staining test and MTT assay and the genotoxicity by the comet assay and micronucleus test, using concentrations between 0.01 and 10 μg/ml. The compound proved to be noncytotoxic in both cell lines, at all tested concentrations, protecting the cells from the DNA damage. In addition, this molecule does not show clastogenic/aneugenic effects when performing the micronucleus test with cytokinesis blockade. Based on the obtained data, and the conditions of the experiments, we can conclude that the 3‐(3,4‐dihydroxyphenyl)‐7,8‐dihydroxycoumarin is a safe molecule up to a concentration of 10 μg/ml, which encourages further studies aiming to explore its potential as a drug candidate. 3‐(3,4‐Dihydroxyphenyl)‐7,8‐dihydroxycoumarin is a newly synthesized coumarin derivative with an antioxidant effect. The objective of this study was to investigate the safety of this compound, assessing the in vitro cytotoxicity and genotoxicity. Concentrations between 0.01 and 10 μg/ml proved to be noncytotoxic by the trypan blue staining test and MTT assay. In addition, this molecule does not show genotoxic damage by the comet assay or clastogenic/aneugenic effects when performing the micronucleus test with cytokinesis blockade. [ABSTRACT FROM AUTHOR]

Background: Genotoxicity in tissues other than hematopoietic tissues, such as the liver and gastrointestinal (GI) tract, is an important focus in the risk assessment of chemicals in humans. We previously developed a rat micronucleus test for the GI tract, which is the first contact tissue where chemicals are introduced into the body through oral exposure. Target cells were obtained from fresh tissue samples by ethylenediaminetetraacetic acid disodium salt (EDTA) treatment. As an improvement to this method, we have used formalin-fixed tissues instead of fresh tissues; this approach can be used for tissues that are sampled from other toxicological tests and that are archived for several years. This new method can be used for examining micronucleus induction retrospectively when needed. In the present study, we compared the performance of the EDTA method and the new method with formalin-fixed tissues (formalin-fixation method). Results: Histological examination showed that both the EDTA and formalin-fixation methods could be used for collecting cells located in or above the proliferative zone of the GI tract tissues of rats. In addition, the collected cells were similar in shape. We conducted micronucleus tests with rat GI tract tissues by the two methods using model chemicals, which were used as positive control chemicals (a combination of diethylnitrosamine, 1,2-dimethylhydrazine dihydrochloride, and potassium bromate). The two methods showed similar results. We additionally evaluated the aging effect of tissues stored in formalin fixative. The results showed that 1 year of storage did not affect the frequency of micronucleated cells. Conclusion: The equivalence of the EDTA and formalin-fixation methods was confirmed, and micronucleus analysis was possible up to at least 1 year after formalin fixation of the GI tract, indicating that the formalin-fixation method is valuable for the rat GI tract micronucleus test. [ABSTRACT FROM AUTHOR]

Background: Orthodontic and orthopedic materials are made of stainless steel, with chemical elements such as nickel and chromium, generally associated with allergenic effects and hypersensitivity, expressed locally. Purpose: To examine, using the micronucleus test in oral mucosa cells, DNA damage in patients undergoing removable metallic orthopedics. Methods: Samples were collected before the appliance adaptation and 30 days later, the buccal cells of each individual were collected by gently brushing the internal part of the cheeks with a cytological brush. The plates were immersed in a Coplin jar with 0.2 % Light Green solution for 1 minute, and then were rinsed with deionized water or Milli Q to remove excess dye. Later, these were placed on a drying plate between 50℃ and 80℃ for 10 to 15 minutes. Results: Compared with the initial samples, after 1 month of orthopedic treatment, a significant increase in the frequency of cells with micronuclei, nuclear budding and karyorrhexis was observed. No changes or evidence of an increase were observed in cells with condensed chromatin. Conclusions: The stages of nuclear alteration that took place during the development of this study were MN frequency, nuclear budding and karyorrhexis, registering a higher frequency in the second sampling and attributed to the presence of removable appliances in the patients. Pyknosis, karyolysis, and karyorrhexis do not constitute stages of nuclear alteration, the latter being the one with the greatest trend observed in the first and second sampling. For this stage, a significant increase in number was found, attributed to the presence of removable appliances in the patients. [ABSTRACT FROM AUTHOR]

It is generally assumed that French fries are likely to have weak in vitro mutagenic activity, but most studies thereof have only assessed gene mutations. In this article, the genotoxicity of 10 extracts of French fries was assessed using the in vitro micronucleus test (following the principles of the OECD 487 guidelines). Each sample was obtained from a different mass catering company in Navarra (Spain). This assay, together with the Ames test, is recommended in the basic in vitro phase included in the European Food Safety Authority Opinion on Genotoxicity Testing Strategies Applicable to Food and Feed Safety Assessment. Eight of 10 samples from mass catering companies induced chromosomal aberrations in the in vitro micronucleus test. Moreover, French fries deep-fried in the laboratory for different periods of time (0, 3, 5, 10, 20, 30 min) were assessed using the in vitro micronucleus test. Genotoxicity was observed in all time periods from 3 min on. The biological relevance of these results must be further explored. [ABSTRACT FROM AUTHOR]

The combination of immunomodulators and antibiotics in the treatment of animals with diseases of bacterial etiology is one of the effective strategies for animal therapy. The drug gentabiferon-B combines antibiotic gentamicin and speciesspecific (bovine) recombinant interferons -α and -γ. The study aimed to evaluate the effect of course application of gentabiferon-B on the cytogenetic stability of bone marrow cells of outbred mice after administering mitomycin C (MMC). The proportion of polychromatophilic erythrocytes in the bone marrow was assessed. There was no effect of gentabiferon-B on the frequency of polychromatophilic erythrocytes with micronuclei in both healthy animals and mice with MMC-induced cytogenetic instability. The course application of gentabiferon-B before the administration of MMC led to an increase in the proportion of polychromatophilic erythrocytes (46.03±2.61%) which was non-significantly different than the negative control group. The administration of MMC alone caused a decrease in the proportion of polychromatophilic erythrocytes to 33.33±1.83%. The antitoxic effect of gentabiferon-B led to an increase in the level of polychromatophilic erythrocytes by 38.1% compared to the group that received only MMC. Studies have shown that gentabiferon-B does not have mutagenic activity and anticlastogenic properties, however, it reduces the toxic effect of MMC. In conclusion, it is indicative that gentabiferon-B has antitoxic properties and can be safely used in animal therapy.

Cellulose nanofibrils (CNFs) are identified as novel nanomaterials with many potential applications. Since CNFs are fibrous manufactured nanomaterials, their potential carcinogenic effects and mesothelial toxicity raise some concerns. In this study, we conducted a standard battery of in vitro and in vivo assays to evaluate the genotoxicity of two CNF types using different manufacturing methods and physicochemical properties. Namely, one was CNF produced via chemical modification by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation, while the other was CNF produced via mechanical defibrillation using needle bleached kraft pulp. A bacterial reverse mutation test and a mouse lymphoma TK assay revealed that CNFs at 100 μg/mL did not induce bacterial reverse mutations and in vitro mammalian cell gene mutation. Further, in vitro chromosomal aberration tests demonstrated that CNFs at 100 μg/mL did not induce chromosomal aberration in Chinese hamster lung fibroblasts. From the mammalian erythrocyte micronucleus test, no statistically significant increase was observed in the proportion of micronucleated polychromatic erythrocytes in the bone marrow cells of rats intratracheally instilled with any concentration of CNFs (0.25–1.0 mg/kg) compared with values from respective negative control groups. Therefore, this battery of in vitro and in vivo assays illustrated that the CNFs examined in this study did not induce genotoxicity, suggesting our results provide valuable insight on the future use of these materials in various industrial applications.

Background: Adjunct chlorhexidine mouthrinse is used routinely in orthodontic clinical practice for plaque control. However, chlorhexidine has genotoxic effects on the oral cells. Moreover, orthodontic appliance leach Ni, Cr metals ions into saliva causing toxicity of surrounding mucosa. Hence, the aim of the study was to assess the periodontal status and genotoxicity in orthodontic patients on fixed mechanotherapy with and without adjunct chlorhexidine using micronucleus (MN) test. Materials and Methods: A randomized control clinical trial was conducted in 30 patients who were on fixed mechanotherapy. The patients were randomly assigned into two treatment groups; Group-A (Control Group): Included 15 patients who are on fixed orthodontic therapy with mechanical plaque control measures only., Group-B (Experimental Group:) included 15 patients on fixed orthodontic therapy with mechanical plaque control and adjunct chlorhexidine mouthrinse (0.2%) for 2 weeks. Periodontal status and genotoxicity using MN test were done at following time points; T0: Just before start of the orthodontic treatment., T1: 2 weeks after start of the orthodontic treatment., T2: 6 weeks after start of the orthodontic treatment., T3: 12 weeks after start of the orthodontic treatment. Results: Plaque index (PI) and bleeding on probing (BOP) were significantly decreased in Group B as compared to Group A in the time intervals; T0-T2, T0-T3, T1-T3 (P < 0.05). Probing pocket depth (PPD) and Clinical attachment level (CAL) showed no significant change in both the groups. The genotoxicity assessed by MN test was significantly increased in Group B than Group A at time intervals; T0-T1, T0-T2 and T0-T3. Conclusion: Adjunct chlorhexidine resulted in decreased PI and BOP scores but nonsignificant change in PPD and CAL. However, the genotoxicity increased significantly in both the groups but more with adjunct chlorhexidine.

Pesticides are considered to be one of the biggest economic and ecological problems in the aquatic ecosystem. Monitoring for toxic effects and screening for different insecticides is vital and crucial for reducing adverse effects on aquatic organisms and public health. Therefore, in this study, we aimed to determine genotoxic effect of acetamipridine in a model fish species, Cyprinus carpio, using the micronucleus test and Comet assay. Common carp (average weight of 1.35 ±0.11g) were exposed to three different concentrations of acetamipridine (0.2, 0.4, and 0.8 g/L) based on previously detected aquatic environmental concentrations, constituting an acute test for a week. At the end of study, the Damage frequency (%), Arbitrary unit and Genetic damage index (%) were evaluated in gill and liver cells of carp by Comet assay. Also, micronucleus frequencies and erythrocyte abnormalities were determined in erythrocytes cells of carp by micronucleus test. Our results revealed significant increases in the frequencies of micronuclei and DNA strand breaks in C. carpio, following exposure to acetamipridine and thus demonstrated the genotoxic potential of this pesticide on fish. Our findings also indicated the suitability of the fish micronucleus test and comet assay in assessment of aquatic genotoxicity of insecticides. [ABSTRACT FROM AUTHOR]

Isotretinoin (ISO), one of vitamin A-derived retinoids, is comparatively the most widely prescribed drug in acne vulgaris pathogenesis. Despite its excellent therapeutic success, the systemic use of this drug showed undesirable serious side effects such as teratogenesis, oxidative stress, and genotoxicity. The uses of retinoids in cancer therapy are limited due to severe adverse reactions. This has led the scientific community to ask for further studies qualifying ISO features and comparing their efficacy and safety. The purpose of this study was to evaluate the cytogenotoxicity of multiple oral doses (5, 10, 15, and 20 mg/kg, daily for seven consecutive days) of ISO in male Sprague-Dawley rats. The micronucleus assay was used to investigate genotoxicity biomarkers such as the percentage of micronucleated polychromatic erythrocytes (%MNPCEs) and the percentage of aberrant cells (%Abc). Another goal was to test the cytotoxicity of the drug by measuring the ratio between PCEs and normochromatic erythrocytes (NCEs) (PCEs/NCEs). In comparison with the control, the three cytogenetic endpoints: %MNPCEs, P/N, and %Abc significantly (P ≤ 0.0017) dose-dependent increase. This suggested genotoxicity and cytotoxicity of the tested ISO doses. Therefore, the therapeutic uses of ISO should be restricted to a very narrow range border. Further studies are needed to shed more light on the safety profile of ISO therapy. [ABSTRACT FROM AUTHOR]

Plant‐based 1,2‐unsaturated Pyrrolizidine Alkaloids (PAs) are responsible for liver genotoxicity/carcinogenicity following metabolic activation, making them a relevant concern for safety assessment. Due to 21st century toxicology approaches, risk of PAs can be better discerned though an understanding of differing toxic potencies, but it is often mixtures of PAs that are found as contaminants in foods, for example, herbal teas and honey, food supplements and herbal medicines. Our study investigated whether genotoxicity potency of PAs dosed individually or in mixtures differed when measured using micronuclei formation in vitro in HepaRG human liver cells, which we and others have shown to be suitable for observing genotoxic potency differences across different PA structural classes. When equipotent concentrations of up to six different PAs representing a wide range of potencies in vitro were tested as mixtures, the observed genotoxic potency aligned favorably with results for single PAs. Similarly, when the BMD confidence intervals of these equipotent mixtures were compared with the confidence intervals of the individual PAs, only minimal variation was observed. These data support a conclusion that for this class of plant impurities, all acting via the same DNA‐reactive mode of action, genotoxic potency can be regarded as additive when assessing the risk of mixtures of PAs. [ABSTRACT FROM AUTHOR]

Coumarins and chalcones are compounds widely found in plants or obtained by synthetic methods which possess several biological properties including antioxidant, anti-inflammatory, and antitumor effects. A series of coumarin-chalcone hybrids were synthesized to improve their biological actions and reduce potential adverse effects. Considering the applications of these molecules, a coumarin-chalcone hybrid [7-methoxy-3-(E)-3-(3,4,5-trimethoxyphenyl) acryloyl-2 H-chromen-2-one] (4-MET) was synthesized and the genotoxic, cytotoxic, and protective effects assessed against damage induced by different mutagens. First, in silico tools were used to predict biological activity of 4-MET which indicated a chemopreventive potential. Subsequently, the genotoxic/antigenotoxic activities of 4-MET were determined both in vitro (Ames test) and in vivo (micronucleus (MN) test and comet assay). In addition, molecular docking simulations were performed between 4-MET and glutathione reductase, an important cellular detoxifying enzyme. Our results indicated that 4-MET was not mutagenic in the Ames test; however, when co-treated with sodium azide or 4-nitroquinoline 1-oxide (4-NQO), 4-MET significantly reduced the harmful actions of these mutagens. Except for a cytotoxic effect after 120 hr treatment, 4-MET alone did not produce cytotoxicity or genotoxicity in the MN test and comet assay. Nonetheless, all treatments of 4-MET with cyclophosphamide (CPA) showed a chemoprotective effect against DNA damage induced by CPA. Further, molecular docking analysis indicated a strong interaction between 4-MET and the catalytic site of glutathione reductase. These effects may be related to (1) damage prevention, (2) interaction with detoxifying enzymes, and (3) DNA-repair induction. Therefore, data demonstrated that 4-MET presents a favorable profile to be used in chemopreventive therapies. [ABSTRACT FROM AUTHOR]

Objectives: 1-Methylnaphthalene (1-MN) is composed of 2 benzene rings and belongs to polycyclic aromatic hydrocarbons. The metabolism of 1-MN in laboratory animals and bacteria leads to the formation of 1-naphthoic acid (1-NA). Material and Methods: In this study the distribution of 1-NA in lung, liver, spleen, kidney and urinary excretion of 1-NA in rats after single and repeated inhalation exposure to 1-MN vapors were investigated. The activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and cytochrome were measured of the rats. Genotoxic effects were evaluated with the in vitro micronucleus test on V79 hamster fibroblasts. Results: The concentrations of 1-NA in the tissues of rats after single and repeated exposure to 1-MN were dependent on the exposure dose. High levels of 1-NA were found in kidneys of animals after the single and repeated exposure to 1-MN. With an increase of 1-MN dose, an increase in the activity of cytochrome P450 (CYP1A1 and CYP1A2) was observed in the liver of rats. Compared to control animals, significantly higher ALT activity was noted in serum of rats exposed to 1-MN. The micronu-clei frequency in V79 cells exposed to 1-MN (in the range of analyzable concentrations; i.e., 5-25 µg/ml) did not differ significantly from the vehicle control, whereas urine extracts from rats exposed to 1-MN induced a significant increase in the frequency of micronuclei compared to urine extracts from the group of control animals. Conclusions: Metabolism of 1-MN in rats after the inhalation exposure leading to 1-NA was mainly observed during the first day after the end of exposure. It is likely that 1-MN metabolites present in rat urine can induce the increased micronuclei frequency as was shown in V79 cells. [ABSTRACT FROM AUTHOR]

Alternariol (AOH) is one of the toxins of Alternaria, and it has been widely detected in a variety of foods. It has been reported to be cytotoxic, dermally toxic, genotoxic, and potentially carcinogenic in vitro. However, in vivo toxicity data are lacking. This study used a novel in vivo 28-day multi-endpoint (Pig-a assay + micronucleus test + comet assay) genotoxicity evaluation system to evaluate the general toxicity and genotoxicity of AOH. A total of 42 male Sprague–Dawley rats were randomly distributed into three AOH-treated groups (5.51, 10.03, and 22.05 µg/kg bw), one AOH high-dose recovery group (AOH-HR, 22.05 µg/kg bw), one positive control group (N-ethyl-N-nitrosourea, 40 mg/kg bw), and two vehicle control groups (corn oil and PBS). Treatments were administered by oral gavage for 28 consecutive days. Histopathological lesions were observed in the liver, kidney, and spleen in all AOH-treated groups. No statistical difference was found in each genotoxicity index within 28 days in the AOH-treated groups compared with those in the corn oil group. On day 42, in the AOH-HR group, the rate of Pig-a mutant phenotype reticulocytes (RETCD59−) significantly increased. On day 56, both RETCD59− and the rate of Pig-a mutant phenotype erythrocytes (RBCCD59−) were significantly reduced. These findings indicated that AOH might cumulatively induce genetic mutations. [ABSTRACT FROM AUTHOR]

Heavy metals contamination in the coastal ecosystem is a source of major concern due to their toxic nature, persistence, and accumulative behaviours. The present study reports the seasonal variability of the biological responses of European hake (Merluccius merluccius, L.1758) collected from the Bay of Oran on the Algerian coast. Besides the condition indexes (gonadosomatic index GSI and Fulton’s condition factor K) and the analysis of metallic trace elements: zinc (Zn), lead (Pb) and cadmium (Cd) in tissues, the micronucleus test was performed in erythrocyte and gill cells to assess the genotoxicity status of the fish. The results revealed a significant correlation between the two fish condition indexes, in link with their reproduction cycle. Highlighting the fact that the study site is under intense stress from toxic contaminants, a significant increase (p value < 0.05) in the frequency of micronuclei occurrence, especially, in the summer period is correlated with significantly (p value < 0.05) high levels of Zn, Pb and Cd. Thus, the test of micronucleus and pollution indicators may serve as a valuable tool in biomonitoring studies of the marine environment since they allowed to reveal genotoxic effects of the investigated fish populations and, consequently, the quality of their biotope. [ABSTRACT FROM AUTHOR]

Socioeconomic and demographic factors, lifestyle and cultural characteristics may play an important role in the development of genetic damage. This damage represents a potential health risk to an individual and increases the risk of developing negative outcomes. The aim of this study was to investigate the association of a set of factors and genetic damage by gathering data from previously studied populations in southern Brazil. This study analyzed data related to genetic damage and socioeconomic, demographic, and lifestyle variables of 514 individuals aged 18 to 64 years, residing in 8 cities located in the extreme south of the Brazil. A total of twelve factors were considered in the analysis, and of these seven had some association with the frequency of micronucleus or some parameter of the comet assay. Interestingly, age was a factor weakly associated with genetic damage, while skin color, occupational exposure, drug use, exposure to radiation, and the cultural habit of consuming chimarrão were shown to be associated with genetic damage when analyzed using multivariate regression. Therefore, we suggest that yerba mate consumption is a confounding factor and should be considered in cytogenetic studies in the southern region of South America. These results reinforce the need for human biomonitoring studies to include consideration of a broad range of population and cultural characteristics when seeking to identify relevant associations. [ABSTRACT FROM AUTHOR]

Introduction. The antiviral properties of imidazolyl ethanamide pentandioic acid (IPA), the active compound of the drug product, has been proven in various experimental models. However, the literature data on the toxicological properties of IPA are limited.Purpose. To evaluate mutagenic and genotoxic properties in in vitro and in vivo models, as well as to study the toxicity of IPA following chronic oral administration to rats and dogs.Materials and methods. Mutagenic and genotoxic properties of IPA were assessed using the Ames test, the test of chromosomal aberrations in human lymphocytes, and the micronucleus test in rats. The chronic toxicity of IPA was studied in Sprague Dawley rats and beagle dogs of both sexes, to which IPA was administered orally at doses of 30-300 mg/kg/day for 26 and 39 weeks, respectively.Results and discussion. In the Ames test, the addition of IPA up to the maximum dose (5000 mcg/plate) did not result in the increase in the number of revertant colonies. At a concentration of up to 5000 mcg/ml, IPA did not cause chromosomal aberrations in human leukocytes. At doses doses ≤ 2000 mg/kg, IPA did not increase the amount of micronuclei in the bone marrow of rats. In chronic experiments, animals tolerated the administration of IPA well: the dose without an observed effect (NOEL) for rats and dogs was 300 mg/kg/day.Conclusion. IPA did not show mutagenic and genotoxic properties in standard in vitro and in vivo tests. With chronic oral administration to rats and dogs, NOEL IPA equal to 300 mg/kg/day provided a systemic exposure that was 8-10 and 41-65 times higher than that in humans, respectively. The results obtained allow us to consider the safety profile of the prolonged use in humans as favorable.

Isotretinoin (ISO), one of vitamin A-derived retinoids, is comparatively the most widely prescribed drug in acne vulgaris pathogenesis. Despite its excellent therapeutic success, the systemic use of this drug showed undesirable serious side effects such as teratogenesis, oxidative stress, and genotoxicity. The uses of retinoids in cancer therapy are limited due to severe adverse reactions. This has led the scientific community to ask for further studies qualifying ISO features and comparing their efficacy and safety. The purpose of this study was to evaluate the cytogenotoxicity of multiple oral doses (5, 10, 15, and 20 mg/kg, daily for seven consecutive days) of ISO in male Sprague-Dawley rats. The micronucleus assay was used to investigate genotoxicity biomarkers such as the percentage of micronucleated polychromatic erythrocytes (%MNPCEs) and the percentage of aberrant cells (%Abc). Another goal was to test the cytotoxicity of the drug by measuring the ratio between PCEs and normochromatic erythrocytes (NCEs) (PCEs/NCEs). In comparison with the control, the three cytogenetic endpoints: %MNPCEs, P/N, and %Abc significantly (P ≤ 0.0017) dose-dependent increase. This suggested genotoxicity and cytotoxicity of the tested ISO doses. Therefore, the therapeutic uses of ISO should be restricted to a very narrow range border. Further studies are needed to shed more light on the safety profile of ISO therapy.

Abstract Pyrostegia venusta (Ker Gawl.) Miers, popularly known as “Cipó-de São-João”, has been used in traditional medicine for its therapeutic properties. Nanotechnology is able to enhance the pharmacological activity of plant extracts. In this context, liposomes and polymeric nanoparticles containing P. venusta ethanolic extract were developed and then physico-chemically characterized to evaluate the mutagenic/antimutagenic effects of P. venusta. In addition, transaminases and serum creatinine were biochemically analyzed for liver and renal damage, respectively. The micronucleus test was performed with male Swiss mice treated orally for 15 consecutive days with free extracts and nanostructured with P. venusta, and then intraperitoneally with N-ethyl-N-nitrosurea (50 mg/kg) on the 15th day of treatment. Micronucleated polychromatic erythrocytes (MNPCE) were evaluated in bone marrow. There was a significant reduction in the frequency of MNPCE (LPEPV = 183% and NPEPV = 114%, p < 0.001), indicating antimutagenic potential of the nanostructured extracts with P. venusta. The groups treated with only nanostructured extract did not show an increase in MNPCE frequency, and biochemical analyzes showed no significant difference between treatments. The liposomes and polymeric nanoparticles containing Pyrostegia venusta ethanolic extract showed biological potential in preventing the first step of carcinogenesis under the experimental conditions.

Abstract We have examined the mutagenic effects of the fungicide Elatus® on tadpoles of Rana catesbeiana and Leptodactylus latrans. Sixty-four tadpoles of each species have been exposed to three concentrations of Elatus® (10, 20, and 50 µg/L-1) during 96 hours. We’ve carried out the micronucleus test (MN) and erythrocyte nuclear abnormalities (ENAs) in 32 tadpoles of each species, the others 32 tadpoles of each species remained in a solution free of Elatus® during 96 hours, in order to assess the ability to recover from the damage caused by the fungicide. There was significant difference in MNs frequency between the treatment exposed to 50µg/L-1 and the control groups for R. catesbeiana, while for L. latrans, we’ve found difference between the treatment of 20 µg/L-1, followed by a period without exposure to the contaminant and the control group when all ENAs were analyzed. When we compared the two species, R. catesbeiana presented a higher frequency of MNs than L. latrans in the treatment exposed to 50 µg/L-1of the fungicide. Our findings highlight the need to monitor amphibians in places where this product is widely used.

Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants, of which BDE-47 could be activated by human cytochrome P450s (CYPs) for chromosome-damaging effects. However, the metabolic activation and mutagenicity of other PBDEs remain unknown. In this study, 14 representative PBDEs were analyzed by molecular docking as potential substrates for several human CYPs. The results showed negative free energies for each pair of binding, however, different CYPs demonstrated largely varied frequencies of binding conformations favoring a substrate potential: CYP2E1, 3A4, and 2B6 being suitable for all/most compounds. Using BDE-99 (5 ∼ 40 μM) as a model compound (exposing for 2 cell cycles), it did not induce micronucleus in a human hepatoma HepG2 cell line, however, positive result was observed in C3A cells (derived from HepG2 but with enhanced expression of CYPs). Pretreatment of HepG2 cells with each of bisphenol A (1 μM, inducer of CYPs) and CITCO (10 μM, inducer of CYP2B6) led to micronucleus formation by BDE-99, while the effect of BDE-99 in C3A cells was abolished by 1-aminobenzotriazole (60 μM, inhibitor of CYPs). In a V79-derived cell line genetically engineered for expressing human CYP2B6 BDE-99 induced micronucleus, while it was negative in V79-Mz and its derivatives expressing several other human CYPs. The micronuclei formed in HepG2 cells pretreated with BPA and CITCO were free of centromere protein B immunofluorescence staining. Finally, BDE-99 weakly induced PIG-A gene mutations in C3A, while negative in HepG2 cells. In conclusion, our study suggest that BDE-99 may be activated by human CYP2B6 for chromosome-breaking effects. [Display omitted] • By molecular docking PBDEs appeared to be substrates for multiple human CYPs. • BDE-99 induced centromere-positive micronucleus and gene mutations in human cells. • BDE-99 mutagenicity depended on metabolic activation, primarily by human CYP2B6. • Induction of CYP2B6 potentiated micronucleus formation by BDE-99 in HepG2 cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • α-glucosidase inhibition, antioxidant and chemopreventive potential were assessed in marolo seeds. • Myricetin and p-coumaric acid were the predominant in marolo seed film flour (MSFF). • Quercetin and rutin were predominant in marolo seed almond flour (MSAF). • MSFF had higher TPC, TFC and antioxidant potential than MSAF. • MSFF showed greater chemopreventive effect and α-glucosidase inhibition than MSAF. The biological effects of marolo (Annona crassiflora Mart.) seed byproducts, a native fruit of Brazilian Cerrado, have not been extensively studied. We evaluated the chemopreventive potential of marolo seed almond flour (MSAF) and marolo seed film flour (MSFF) and correlated the results obtained with the antioxidant capacity presented by the seed. Total phenolic content (TPC) and total flavonoid content (TFC) were determined by spectrophotometric analysis and phenolics profile composition by Ultra-Performance Liquid Chromatography (UPLC). In addition, the in vitro antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+) expressed in trolox equivalent (TE) of MSFF (165 and 325 µmol TE/g) and MSAF (7.21 and 4.34 µmol TE/g), respectively. MSFF displayed of antioxidant activity values by DPPH (165.98 µmol TE/g) and ABTS•+ (323.13 µmol TE/g) and TPC, expressed in gallic acid equivalent (GAE), of 54.28 mg GAE/g with predominance of myricetin (368.17 µg/g), and TFC, expressed in catechin equivalent (CE), of 50.86 mg CE/g, representing ∼ 93 % of the TPC. MSAF presented TPC of 1.52 mg GAE/g, with TFC of 0.76 mg CE/g (∼50 % of TPC), with predominance of quercetin (29.08 µg/g). The chemopreventive activity against DNA damage induced by doxorubicin (DXR) [20 mg/kg body weight (bw)]) was evaluated in Swiss mice peripheral blood by micronucleus test. Toxicological parameters, such as food and water consumption and animal weight, as well as blood glucose levels, were monitored during 14 days of treatment. The results showed that MSFF and MSAF presented no significant cytotoxic and mutagenic effects. The MSFF at doses of 3.5, and 7.0 mg/day showed a chemopreventive effect, while in the doses of 14.0 and 28.0 mg/day, no effect was observed. On the other hand, in the MSAF, a chemopreventive effect was observed only in the dose of 28 mg/day. The interference of one or more of the bioactive compounds with antioxidant activity presents in the MSFF may explain the best protective effect against DNA damage. Therefore, both marolo seed flours (MSFF and MSAF) can be considered potential food ingredients products that could be applied in food or pharmaceutical preparations with antioxidant and chemopreventive properties. [ABSTRACT FROM AUTHOR]

Schinus molle L. is a medicinal species belonging to the Anacardiaceae family. It is commonly referred to as "aroeira" and its leaves and roots are utilized for treating different pathological conditions. However, despite its widespread use in traditional medicine, there is a lack of in-depth toxicological studies. To evaluate the acute toxicity and genotoxicity of S. molle aqueous extract/ethanol-soluble fraction in rats. First, a purified aqueous extract was obtained from the leaves of S. mole through infusion (referred to as EESM) and its compounds were identified using LC-DAD-MS data. Female rats were then subjected to acute oral toxicity tests using doses of 5, 50, 300, and 2000 mg/kg of ESSM. Studies on genetic material, including the micronucleus test and comet assay, were conducted on male and female Wistar rats using the same doses as in the acute toxicity test. For both assays, ESSM was administered orally. The main metabolites annotated from ESSM were dimeric proanthocyanidins, phenylpropanoids acids, flavan-3-ols, simple organic acids (C6–C1), a flavonol di- O -glycosylated (rutin), and O -glycosylated megastigmane. The ESSM did not exhibit any acute toxic effects, such as changes in biochemical, hematologic, or histopathological analysis. Furthermore, no changes were observed in comet assay or micronucleus tests when rats were given doses of 5, 50, 300, or 2000 mg/kg of ESSM. The results showed that the ESSM does not induce acute toxicity or exhibit genotoxicity up to a dose of 2000 mg/kg. [Display omitted] • Schinus molle L. is a medicinal species belonging to the Anacardiaceae family. • Despite its widespread use there is a lack of in-depth toxicological studies. • The aqueous extract/ethanol-soluble fraction (ESSM) did not exhibit any acute toxic effects. • No changes were observed in comet assay or micronucleus tests. • ESSM does not induce toxicity up to a dose of 2000 mg/kg. [ABSTRACT FROM AUTHOR]

Lancehead snakes of the genus Bothrops are responsible for 90% of the snakebites in Latin America. The objective of this study was to assess the LD 50 , physical, and hematological manifestations induced by B. atrox venom in male and female mice inoculated by different routes. B. atrox venom was inoculated in male and female mice by intramuscular (IM), subcutaneous (SC), intravenous (IV), and intraperitoneal (IP) routes. B. atrox venom LD 50 was lower in male than female groups, regardless of the injection route. However, it was the lowest when the venom was inoculated by the IP route. Moreover, comparisons between male and female responses according to the injected venom dose showed higher edema-forming, local hemorrhagic, dermonecrotic, and myotoxic activities in male than in female mice. While the minimal hemorrhagic, and necrotic doses were not statistically different between the two groups, the difference between males and females was more pronounced at high venom doses. Hematological parameter changes were also more significant in male than in female mice. The venom decreased the levels of total leukocytes after 24 h of injection in male and female mice, with a more profound decrease in the male group. The micronucleus test, a tool for genotoxicity assessment, documented the mutagenic effects of B. atrox on leucocytes. We demonstrate the higher susceptibility of male mice to B. atrox venom than females. Sex differences must be considered when conducting experimental studies on snake venoms. [Display omitted] • Studies on toxic manifestations related to snake venom did not provide information on the laboratory animals' sex. • Sexual dimorphism can affect the innate and adaptive immune responses. • Male mice are more susceptible to B. atrox venom than females. • The intraperitoneal route of venom injection showed the most serious toxic effect in mice. • Sex differences must be considered when conducting experimental studies on snake venoms. [ABSTRACT FROM AUTHOR]

Carboplatin is amongst the most commonly used anticancer drugs for the management of several human malignancies. However, it has displayed genotoxic properties against normal cells. Evaluation of natural products for their protective effects against chemotherapeutic drug induced toxicity has been growing in recent years. A naturally occurring flavonoid, chrysin, has strong antioxidant abilities and protects against DNA impairment. This study used multiple assays to evaluate the levels of damage to DNA in normal cells and to examine any possible protective role of chrysin against such damage. Male BALB/c mice were administered chrysin orally in two doses of 20 and 40 mg/kg for 10 consecutive days and then a single injection of carboplatin [90 mg/kg body weight (b.w.)] was administered intraperitoneally to induce carboplatin toxicity. 24 h after the carboplatin injection, mice were sacrificed. DNA damage was evaluated using several genotoxicity tests (8-Hydroxydeoxy-guanosine marker, comet assay, micronucleus test, and chromosomal aberration assay) to identify diverse types of damage to the DNA. The results suggest that pretreatment with chrysin significantly decreased the level of DNA damage caused by carboplatin probably due to its potent antioxidant traits. Therefore, chrysin can be considered to be developed as a chemoprotective agent against chemotherapy associated side-effects. [ABSTRACT FROM AUTHOR]

Methanol extracts of A. absinthium, A. annua, A vulgaris, A. scoparia, and A. alba from Serbia at concentrations of 1.00; 2.00 and 4.00 μg/ml, and as pure compounds identified in examined extracts (ferulic acid, rutin, rosmarinic acid, and quercetin) were examined for their effects on micronucleus distribution in human lymphocytes in vitro. All extracts greatly reduced the number of micronuclei in the concentration of 2.00 μg/ml comparing to the control, whereby A. alba extract exhibited the most prominent effect on decreasing frequency of micronucleus (45.2%), followed by extracts of A. vulgaris, A. absinthium, A. scoparia and A. annua. The same declining trend was observed for the extracts at concentrations of 4.00 µg/ml, and 1.00 µg/ml, respectively. Among pure compounds (concentration 2.00 μg/ml), rutin showed the most pronounced effect on decreasing frequency of micronucleus (41.7%), higher than ferulic acid, quercetin, and rosmarinic acid comparing to the control. [ABSTRACT FROM AUTHOR]

Background: Adjunct chlorhexidine mouthrinse is used routinely in orthodontic clinical practice for plaque control. However, chlorhexidine has genotoxic effects on the oral cells. Moreover, orthodontic appliance leach Ni, Cr metals ions into saliva causing toxicity of surrounding mucosa. Hence, the aim of the study was to assess the periodontal status and genotoxicity in orthodontic patients on fixed mechanotherapy with and without adjunct chlorhexidine using micronucleus (MN) test. Materials and Methods: A randomized control clinical trial was conducted in 30 patients who were on fixed mechanotherapy. The patients were randomly assigned into two treatment groups; Group-A (Control Group): Included 15 patients who are on fixed orthodontic therapy with mechanical plaque control measures only., Group-B (Experimental Group:) included 15 patients on fixed orthodontic therapy with mechanical plaque control and adjunct chlorhexidine mouthrinse (0.2%) for 2 weeks. Periodontal status and genotoxicity using MN test were done at following time points; T0: Just before start of the orthodontic treatment., T1: 2 weeks after start of the orthodontic treatment., T2: 6 weeks after start of the orthodontic treatment., T3: 12 weeks after start of the orthodontic treatment. Results: Plaque index (PI) and bleeding on probing (BOP) were significantly decreased in Group B as compared to Group A in the time intervals; T0-T2, T0-T3, T1-T3 (P < 0.05). Probing pocket depth (PPD) and Clinical attachment level (CAL) showed no significant change in both the groups. The genotoxicity assessed by MN test was significantly increased in Group B than Group A at time intervals; T0-T1, T0-T2 and T0-T3. Conclusion: Adjunct chlorhexidine resulted in decreased PI and BOP scores but nonsignificant change in PPD and CAL. However, the genotoxicity increased significantly in both the groups but more with adjunct chlorhexidine. [ABSTRACT FROM AUTHOR]

Background: Fluorides are an essential component of oral hygiene products used to prevent dental decay. Therefore, a question arises about the potential harms of joint use of fluoridated toothpaste and mouthwashes regarding the increased amount of fluoride in the oral mucosa. Methods: This prospective, double-blinded parallel randomized clinical trial was conducted using a buccal micronucleus cytome assay (BMCyt assay). Forty-one participants were randomly assigned to the two groups. All participants used the same kinds of toothpaste for 12 weeks, designed explicitly for this study (non-fluoride, 1050 ppm F, and 1450 ppm F each for 4 weeks). Simultaneously, during the 3 months of the research, one group used mouthwash with fluoride (450 ppm) and another without fluoride. The buccal mucosal sampling was taken before using the tested products and after 4, 8, and 12 weeks of their use. Results: The frequency of micronuclei and the majority of other scored endpoints from the BMCyt assay showed no statistically significant differences within and between the studied groups. Comparing two groups, only statistically significant increases in the number of cells with nuclear buds (p = 0.048) and karyorrhexis (p = 0.020) at four weeks of usage were observed in the group that used mouthwash with fluoride. Conclusion: On the basis of the results, it can be concluded that simultaneous application of fluoridated toothpaste and fluoride mouthwash does not lead to cytogenetic damage in buccal mucosal cells. [ABSTRACT FROM AUTHOR]

Pistacia lentiscus L. is one of the most popular medicinal plants attributed to its beneficial properties on human health. However, few toxicogenetic studies have been carried out. Therefore, the aim of this study was to examine the potential genotoxic/antigenotoxic and mutagenic/antimutagenic properties of oil, ethyl acetate and ethanolic extracts of P. lentiscus L. fruits using in vitro the Ames and Umu assays, as well as in vivo micronucleus (MN) test. Extracts did not exert any significant mutagenic/genotoxic effects but provided protection against standard mutagenic and genotoxic agents including 2 nitrofluorene (2-NF) at 2.5 and 5 µg/ml; sodium azide at 5 and 10 µg/ml; 3-methylcholanthrene (3-MC) at 25 and 50 μg/ml; cyclophosphamide (CP) at 50 and 100 μg/ml; 4-nitroquinoline 1-oxide (4-NQO) at 0.05 µg/ml and 2-amino-anthracene (AA) at 0.2 µg/ml. Further, cytotoxicity and selectivity were examined on human hepatocarcinoma (HepG2), and MCF-7 breast cancer cell lines as well as a human normal-like fibroblast cell line (TelCOFS02MA) using MTT assay. Among all extracts, PF1 (ethanolic) showed the most significant selectivity index (SI) (HepG2:11.98; MCF7:4.83), which led to further investigations using an animal model. Oral administration of PF1 (125–1000 mg/kg b.w.) significantly decreased the number of micronucleated cells in CP -initiated (50 mg/kg b.w.) mice, while the number of micronucleated reticulocytes (MNRET), micronucleated polychromatic erythrocytes (MNPCE) or mitotic index (MI) were not markedly affected. Further, PF1 significantly enhanced catalase (CAT) and superoxide dismutase (SOD) activities in the livers and kidneys of these animals. The obtained results indicated the beneficial properties of P. lentiscus L. fruits for use in therapy against harmful effects of genotoxic and mutagenic agents. However, while promising it should be noted that the obtained results are preliminary and need to be confirmed prior to therapeutic use. [ABSTRACT FROM AUTHOR]

• Libidia ferrea aqueous extract is rich in tannins and flavonoids. • The fractions were able to reduce biofilm formation up to 71%. • The fractions do not present cytotoxicity and genotoxicity according to in vitro asssays. Libidibia ferrea (Mart. Ex Tul) L. P. Queiroz (Fabaceae) is a typical Caatinga species, 53 commonly known as "Brazilian ironwood" and "leopard tree" and has been used in folk 54 medicine in the treatment of several diseases such as anemia, ulcer, hypertension, 55 diabetes, and antimicrobial agent. However, its adverse effects on human health are not 56 entirely known. The present work aimed to investigate the chemical composition, 57 antibiofilm formation, and cytogenotoxicity potential of Libidia ferrea aqueous extract 58 (AELf). Phytochemical screening, chromatographic analyses, and fractionation were 59 performed to characterize AELf. Additionally, the AELf effect on Staphylococcus aureus 60 biofilm formation was also investigated. Also, twelve extract concentrations were tested 61 by the MTT assay to verify cytotoxicity, while genotoxic (cytokinesis-block 62 micronucleus assay - CBMN) evaluations were carried out on PBMC cells using three 63 different concentrations (10, 20, and 30 mg/mL). The phytochemical analysis revealed 64 the presence of flavonoids, proanthocyanidins, leucoanthocyanidins, and hydrolyzable 65 tannins in higher concentrations. As also, AELf was able to inhibit biofilm formation (≥ 66 50%) on the tested strain by up to 55.3% (44.7 ± 7.8) and 71.1% (28.9 ± 3.4) at 67 concentrations 1.25 mg/mL and 2.5 mg/mL, respectively. AELf concentrations used in 68 the MTT and CBMN assays showed no cytotoxic and genotoxicity activity. The aqueous 69 extract of L. ferrea var. ferrea fruit presents good potential for the future development of 70 antimicrobial products since concentrations around 2.5 mg/mL showed antibiofilm 71 activity. Additionally, the aqueous extract has a good safety profile. [ABSTRACT FROM AUTHOR]

The impact of atrazine and nitrate, the most used pesticide and fertilizer, on the health of Sclerophrys regularis was investigated in this study. We exposed the tadpole of Sclerophrys regularis to atrazine and nitrates to assess abnormalities and genotoxicity as biomarkers for environmental impacts. The proportional malformed toads were shown to be high when treated with nitrate alone (17%) or in combination (13%) or even treated with atrazine alone (the minimal, 5%), limbs and tail deformities are the most observed. Also, abnormal activity and movement were detected at all treated groups. In addition, Genotoxicity was measured by micronucleus test (MN) in detection of nuclear abnormalities in given species. The results indicate that individuals exposed to atrazine or nitrate or that exposed to both, exhibited a significantly higher degree (p < 0.01) of nuclear lesions. These results constitute key assessment of developing abnormalities and MN test in this species in Egypt and suggest that developing abnormalities and/or MN test and the degree of nuclear lesions of RBCs can be a useful indicator of the degree of environmental stress and ecosystem disrupting experienced by amphibian populations. [ABSTRACT FROM AUTHOR]

Abstract Background and aim Approximately, 2 million tonnes of pesticides are utilized annually worldwide. Phosalone (Pln), an organophosphorus pesticide, acts as an insecticide and acaricide to control pests of crops such as nuts, citrus fruits, pomegranates, stone fruits, grapes, potatoes, and artichokes. The purpose of this study was to evaluate the possible genotoxic effects following exposure to Pln in the cells derived from mouse red bone marrow. Materials and methods Sixty mice were divided into 6 groups including cyclophosphamide (40 mg/kg, IP) and Pln (6, 12, 20, and 40 mg/kg) exposure by gavage. After 1 and 5 days of exposure, animals were euthanized and the genotoxicity assays were done on bone marrow extracted cells. Results Comet assay shows a time and dose-dependent toxicity which further DNA degradation is observed after 5-day exposure (p