Toxicological studies are important to investigate the genotoxic effects of various substances. Allium cepa can be used as test model for this purpose. This review summarizes the scope and applications for this A. cepa test model. For this, an up-to-date (April 2023) literature search was made in the Science Direct, PubMed, and Web of Science databases to find published evidence on studies performed using A. cepa as a test model. Out of 3,748 studies, 74 fit the inclusion criteria. The results showed that the use of the test model A. cepa contributed considerably to measuring the toxicological potential of plant extracts, proving the efficacy of the test as a potent bioindicator of toxic effects. In addition, 27 studies used more than one test system to verify the toxicological potential of extracts and fractions. Studies have shown that the A. cepa model has the potential to replace other test systems that make use of animals and cell cultures, besides having other advantages such as low cost, ease of execution, and good conditions for the observation of chromosomes. In conclusion, the A. cepa test can be considered one of the potential biomonitoring systems in toxicological studies of crude extracts.

The skin is the largest organ in the body and the only one to come into contact with solar UV radiation (UVR). UVA (320-400 nm) is a significant contributor to UV-related skin damage. The UVA spectrum makes up over 95% of solar-UV energy reaching the earth\'s surface causing the majority of the visible signs of skin photoaging. Many consumer products also emit UVA, including nail dryers. There have been sporadic reports suggesting that these units may be contributing to skin cancer incidence. This notion was recently bolstered by a finding that nail dryer-irradiated mammalian skin cells develop a mutational signature consistent with UVA exposure. This report was surprising considering the comparatively low level of UVA to which the skin is exposed during nail treatments. In this research, we investigated how UVA-emitting devices caused cytotoxic/genotoxic impact after only low levels of UVA exposure. Our data showed that levels of UVA in the unit are highly variable and location dependent. We confirm previous reports that using prolonged exposure protocols could induce significant levels of DNA damage. It was also determined that UV-induced DNA damage only partially correlated with the level of UVA fluency. On investigation, we found that the unit had a rapid increase in internal temperature when in use. Exposing human cells to these elevated temperatures acted synergistically with UVA to magnify the cytotoxic and genotoxic impact of UV irradiation.

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Essential oil content of and phenolic compounds flower-fruit, root, and aerial parts of Heracleum pastinacifolium subsp. incanum were analysed by GC/MS and LC/MS methods, respectively. Antidiabetic, anticholinesterase, and antioxidant activities of flower-fruit, root, aerial parts methanol extracts were evaluated. Apiole (35.0%), myristicine (72.2%), and myristicine (15.1%) were found as major compounds of fruit-flower mixture, root, aerial part essential oils, respectively. Hesperidin was found the highest amount in aerial part and flower-fruit extracts with 8904.2621 ng/mL and 11558.3634 ng/mL values, respectively. Fruit-flower extract showed the highest activity against α-glucosidase (24%). Root extract demonstrating the highest activity (18%) against AChE enzyme. Flowers-fruits mixture methanol extract had a higher % inhibition value on ABTS·+ and DPPH•. Flowers-fruits mixture methanol extract was rich in total phenol, total tannin, and protein content. All the extracts were determined as genetoxically safe according to the results of Ames/Salmonella, Escherichia coli WP2 and Allium cepa assays.

Cancer is a disease resulting from the disruption of cell cycle regulation, leading to the abnormal and unchecked proliferation of cells. Medicinal plants are rich in various bioactive phytochemicals or nutritional compounds. The aim is to determine the cytotoxic and genotoxic effects of ethanolic extracts of Macaranga peltata leaves on human oral cancer cell lines. The study setting was centre for Research on Molecular and Applied Sciences, Azeezia College of Dental Sciences and Research. The study design is a Comparative In Vitro study. Shade dried leaves of Macaranga peltata were subjected to Soxhlet extraction, and ethanolic extract was prepared. In vitro cytotoxic effects on human oral cancer cell lines were evaluated by (3-(4,5-dimethyl thiazole-2yl)-2,5-diphenyl tetrazolium bromide) MTT assay, and genotoxic effect was evaluated by comet assay. Untreated cell lines were used as control, and 5-fluorouracil was used as positive control. All experiments were performed in triplicates, and results were represented as Mean+/- SE. One-way ANOVA and Dunnet test were performed to analyze data. ***P < 0.001 compared with the control group. The ethanolic extract of Macaranga peltata exhibited cytotoxicity against oral cancer cells (LC50: 40.193089 μg/ml). There was a concentration-dependent increase in cell death, and at 100 μg/ml, the extract was most effective, causing 50% inhibition of viability. The comet assay showed significant genotoxic effects compared with 5-fluorouracil and untreated oral cancer cell lines. The ethanolic extract of Macaranga peltata leaves was subjected to MTT assay and comet using KB cell lines. The study concludes that the extract gave promising result for the anticancer activity on the KB cell lines producing cytotoxicity and genotoxicity.

<b>Background and Objective:</b> Gamma irradiation induces genotoxicity, characterized by the formation of extra-nuclear bodies and left behind during the anaphase stage of cell division, often referred to as a micronucleus (MN). The present work aims to monitor exposure to ionizing radiation as a genotoxic agent in the lymphocytes of workers at radiation energy centers. <b>Materials and Methods:</b> The lymphocyte cytokinesis block micronucleus assay used and analyzed the correlation between the Nuclear Division Index (NDI), age, blood type and the number of micronuclei (MN). Blood samples were collected from 20 volunteers in heparin tubes, exposed to 2 Gy gamma rays and cultured <i>in vitro</i>. <b>Results:</b> A significant difference in the number of micronuclei between blood group A and blood groups A, B and AB. The Nuclear Division Index (NDI) value for lymphocytes of radiation energy center workers after gamma radiation was significant (1.74±0.1) but still within the normal range. Neither MN frequency nor NDI values correlated with age, but MN frequency showed a correlation with blood type. <b>Conclusion:</b> The gamma irradiation did not induce a cytostatic effect but proved genotoxic to the lymphocytes of radiation energy center workers. Notably, blood type A demonstrated higher sensitivity to gamma radiation.

The current review intends to regulate and accurately evaluate genotoxic contaminants in drug substance and drug product method and formulation process development, validation, and degradation pathways. The Quality by Design (QbD) principles can be applied to the systematic evaluation and control of impurities enabled by the development of modern analytical techniques, including the performance of risk assessment, the screening of Critical Process Parameters (CPPs), and the identification of the most influential variables in the optimization of the evaluation and control methods. Current difficulties in removing genotoxic contaminants and the procedures for doing so have been outlined in this review, along with the steps necessary to acquire optimum techniques and the most acceptable formulations. In addition to this, division, characterization, assessment, quantification, and formation of genotoxic impurities sources and control strategy for genotoxic impurities, handling of nitrosamine assay content of drug products in different industrial methodologies and their chemometric prospects and associated recent patents are also explored.

UNASSIGNED: DNA damage repair (DDR) is an essential process for living organisms and contributes to genome maintenance and evolution. DDR involves different pathways including Homologous recombination (HR), Nucleotide Excision Repair (NER) and Base excision repair (BER) for example. The activity of each pathway is revealed with particular drug inducing lesions, but the repair of most DNA lesions depends on concomitant or subsequent action of the multiple pathways.
UNASSIGNED: In the present study, we used two genotoxic antibiotics, mitomycin C (MMC) and Bleomycin (BLM), to decipher the interplays between these different pathways in E. coli. We combined genomic methods (TIS and Hi-SC2) and imaging assays with genetic dissections.
UNASSIGNED: We demonstrate that only a small set of DDR proteins are common to the repair of the lesions induced by these two drugs. Among them, RecN, an SMC-like protein, plays an important role by controlling sister chromatids dynamics and genome morphology at different steps of the repair processes. We further demonstrate that RecN influence on sister chromatids dynamics is not equivalent during the processing of the lesions induced by the two drugs. We observed that RecN activity and stability requires a pre-processing of the MMC-induced lesions by the NER but not for BLM-induced lesions.
UNASSIGNED: Those results show that RecN plays a major role in rescuing toxic intermediates generated by the BER pathway in addition to its well-known importance to the repair of double strand breaks by HR.

UNASSIGNED: Waterpipe tobacco smoking (WTS) is an issue all over the world, although it is particularly prevalent in the Middle East, and Southeast Asia. The genotoxic effects of smoking were reported to be associated with nucleus abnormalities such as micronuclei (MN), karyorrhexis (KR), karyolysis, pyknosis, binucleates, broken eggs, condensed chromatin in exfoliated buccal mucosal cells, and was believed to be associated with apoptosis of cells and was not correlated to the exposure time.
UNASSIGNED: The aim of this study was to evaluate and compare the cytotoxic and genotoxic effects of cigarette and WTS on buccal mucosa.
UNASSIGNED: The pertinent search was done through the computerized literature on MEDLINE, EMBASE, and PUBMED databases, which included case-control, clinical and observational studies regarding the mutagenic effects of cigarettes and WTS in oral tissues. The retraction of data in this study was undertaken from May 2010 to May 2022. A total of 60 articles from the search data were retrieved. This investigation was registered with the research center of Riyadh Elm University for institution review board approval (IRB) and obtained the IRB number \"FRP/2021/448/733/707 and the systematic review registration number with respect to PROSPERO is 345417.
UNASSIGNED: After the removal of duplicates, 32 were evaluated for the inclusion and exclusion criteria. Out of 32 articles, twenty studies were evaluated for cytogenetic abnormalities in buccal mucosal cells of waterpipe tobacco smokers (WTS) and cigarette smokers, and 12 were excluded. The mean MN levels in the oral tissues of WTS were more (1.94 ± 0.39) than in non-smokers (1.68 ± 0.35).
UNASSIGNED: Therefore, we conclude that the MN count can be employed as a biomarker and preliminary signal for the identification of changes in oral mucosa among smokers, which develop towards cancer formation.

Complexes of coinage metals can potentially be used as alternatives to platinum-based chemotherapeutic drugs. Silver is a coinage metal that can potentially improve the spectrum of efficacy in various cancers treatment, such as malignant melanoma. Melanoma is the most aggressive form of skin cancer that is often diagnosed in young and middle-aged adults. Silver has high reactivity with skin proteins and can be developed as a malignant melanoma treatment modality. Therefore, this study aims to identify the anti-proliferative and genotoxic effects of silver(I) complexes with mixed-ligands of thiosemicarbazones and diphenyl(p-tolyl)phosphine ligands in the human melanoma SK-MEL-28 cell line. The anti-proliferative effects of a series of silver(I) complex compounds labelled as OHBT, DOHBT, BrOHBT, OHMBT, and BrOHMBT were evaluated on SK-MEL-28 cells by using the Sulforhodamine B assay. Then, DNA damage analysis was performed in a time-dependent manner (30 min, 1 h and 4 h) by using alkaline comet assay to investigate the genotoxicity of OHBT and BrOHMBT at their respective IC50 values. The mode of cell death was studied using Annexin V-FITC/PI flow cytometry assay. Our current findings demonstrated that all silver(I) complex compounds showed good anti-proliferative activity. The IC50 values of OHBT, DOHBT, BrOHBT, OHMBT, and BrOHMBT were 2.38 ± 0.3 μM, 2.70 ± 0.17 μM, 1.34 ± 0.22 μM, 2.82 ± 0.45 μM, and 0.64 ± 0.04 μM respectively. Then, DNA damage analysis showed that OHBT and BrOHMBT could induce DNA strand breaks in a time-dependent manner, with OHBT being more prominent than BrOHMBT. This effect was accompanied by apoptosis induction in SK-MEL-28, as evaluated using Annexin V-FITC/PI assay. In conclusion, silver(I) complexes with mixed-ligands of thiosemicarbazones and diphenyl(p-tolyl)phosphine exerted anti-proliferative activities by inhibiting cancer cell growth, inducing significant DNA damage and ultimately resulting in apoptosis.