Investigation of multidirectional toxicity induced by high-dose molybdenum exposure with Allium test.

In this study, the multifaceted toxicity induced by high doses of the essential trace element molybdenum in Allium cepa L. was investigated. Germination, root elongation, weight gain, mitotic index (MI), micronucleus (MN), chromosomal abnormalities (CAs), Comet assay, malondialdehyde (MDA), proline, superoxide dismutase (SOD), catalase (CAT) and anatomical parameters were used as biomarkers of toxicity. In addition, detailed correlation and PCA analyzes were performed for all parameters discussed. On the other hand, this study focused on the development of a two hidden layer deep neural network (DNN) using Matlab. Four experimental groups were designed: control group bulbs were germinated in tap water and application group bulbs were germinated with 1000, 2000 and 4000 mg/L doses of molybdenum for 72 h. After germination, root tips were collected and prepared for analysis. As a result, molybdenum exposure caused a dose-dependent decrease (p < 0.05) in the investigated physiological parameter values, and an increase (p < 0.05) in the cytogenetic (except MI) and biochemical parameter values. Molybdenum exposure induced different types of CAs and various anatomical damages in root meristem cells. Comet assay results showed that the severity of DNA damage increased depending on the increasing molybdenum dose. Detailed correlation and PCA analysis results determined significant positive and negative interactions between the investigated parameters and confirmed the relationships of these parameters with molybdenum doses. It has been found that the DNN model is in close agreement with the actual data showing the accuracy of the predictions. MAE, MAPE, RMSE and R2 were used to evaluate the effectiveness of the DNN model. Collective analysis of these metrics showed that the DNN model performed well. As a result, it has been determined once again that high doses of molybdenum cause multiple toxicity in A. cepa and the Allium test is a reliable universal test for determining this toxicity. Therefore, periodic measurement of molybdenum levels in agricultural soils should be the first priority in preventing molybdenum toxicity.

Genotoxic effects induced by iprodione and tebuconazole in meristematic cells of Allium cepa: responses dependent on concentration and exposure time.

The present work explores the genotoxicity of the fungicides iprodione (IP) and tebuconazole (TB) using the Allium cepa assay as an in vivo biological model. Both short-term and long-term exposures were studied, revealing concentration- and time-dependent cytological and genotoxic effects. IP exhibited genotoxicity over a wider concentration range (5-50 µg/ml) and required 30 h of exposure, while TB showed genotoxicity at higher concentrations (10 and 30 µg/ml) within a 4-h exposure period. The study highlights the importance of assessing potential risks associated with fungicide exposure, including handling, disposal practices, and concerns regarding food residue. Moreover, the research underscores the genotoxic effects of IP and TB on plant cells and provides valuable insights into their concentration and time-response patterns.

In-vivo and in-silico studies to identify toxicity mechanisms of permethrin with the toxicity-reducing role of ginger.

In this study, the toxic effects of permethrin on Allium cepa L. and the protective role of Zingiber officinale rhizome extract (Zoex) were investigated. In this context, 6 different groups were formed. While the control group was treated with tap water, the groups II and III were treated with 10 µg/mL and 20 µg/mL Zoex, respectively, and the group IV was treated with 100 µg/L permethrin. The protective effect of Zoex against permethrin toxicity was studied as a function of dose, and groups V and VI formed for this purpose were treated with 10 µg/mL Zoex + 100 µg/L permethrin and 20 µg/mL Zoex + 100 µg/L permethrin, respectively. After 72 h of germination, cytogenetic, biochemical, physiological, and anatomical changes in meristematic cells of A. cepa were studied. As a result, permethrin application decreased the mitotic index (MI) and increased the frequency of micronuclei (MN), and chromosomal abnormalities. The increase in malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) and the decrease in glutathione (GSH) indicate that permethrin causes oxidative damage. Compared to the control group, a 68.5% decrease in root elongation (p < 0.05) and an 81.8% decrease (p < 0.05) in weight gain were observed in the permethrin-treated group. It was found that the application of Zoex together with permethrin resulted in regression of all detected abnormalities, reduction in the incidence of anatomical damage, MN and chromosomal aberrations, and improvement in MI rates. The most significant improvement was observed in group VI treated with 20 µg/mL Zoex, and Zoex was also found to provide dose-dependent protection. The toxicity mechanism of permethrin was also elucidated by molecular docking and spectral studies. From the data obtained during the study, it was found that permethrin has toxic effects on A. cepa, a non-target organism, while Zoex plays a protective role by reducing these effects.

In vitro and in vivo genotoxicity evaluation of ALP1018, a nanomineral food supplement.

The use of nano-based dietary supplements is increasing around the world, as nanotechnology can help enhance nutrient bioavailability. ALP1018 is a newly developed iron-zinc complex supplement designed as a nanoformulation to improve the efficacy of iron and zinc supplementation. However, safety concerns have been raised, as there is no clear evaluation of ALP1018 toxicity. The goal of this study was to determine the potential mutagenicity and genotoxicity of ALP1018 through three standard screenings: the Ames test, which evaluates bacterial reverse mutations; the in vitro test of chromosomal aberration in Chinese hamster lung cells; and the in vivo micronucleus assay using ICR mice. ALP1018 showed no mutagenic effect, as no increase was observed in the presence or absence of metabolic activation (S9 mix) in revertant colonies on all the bacterial strains used in the Ames test. No structural chromosomal abnormalities were observed in the presence or absence of the S9 mix in mammalian cells used in the chromosomal aberration assay. In the micronucleus test, the frequency of micronucleated polychromatic erythrocytes was not significantly increased in mouse bone marrow cells. Based on these findings, we can conclude that ALP1018 is safe to use and has no mutagenic or genotoxic potential.

Effect of Melissa officinalis L. leaf extract on manganese-induced cyto-genotoxicity on Allium cepa L.

Although the antioxidant properties of Melissa officinalis extract (Mox) are widely known, little work has focused on its protective capacity against heavy metal stress. The primary objective of this study was to determine the potential of Mox to mitigate manganese (II) chloride (MnCI2)-induced cyto-genotoxicity using the Allium and comet assays. Physiological, genotoxic, biochemical and anatomical parameters as well as the phenolic composition of Mox were examined in Allium cepa (L.). Application of 1000 µM MnCl2 reduced the rooting percentage, root elongation, weight gain, mitotic index and levels of chlorophyll a and chlorophyll b pigments compared to the control group. However, it increased micronuclei formation, chromosomal abnormality frequencies, tail DNA percentage, proline amount, lipid peroxidation level and meristematic damage severity. The activities of superoxide dismutase and catalase also increased. Chromosomal aberrations induced by MnCl2 were fragment, sticky chromosome, vagrant chromosome, unequal distribution of chromatin and bridge. Application of 250 mg/L Mox and 500 mg/L Mox along with MnCl2 significantly alleviated adverse effects dose dependently. The antioxidant activity bestowed by the phenolic compounds in Mox assisted the organism to combat MnCl2 toxicity. Consequently, Mox exerted remarkable protection against MnCl2 toxicity and it needs to be investigated further as a potential therapeutic option.

Evaluation of the probable synergistic toxicity of selected potentiated antiretroviral and antibiotics on some aquatic biomarker organisms.

Environmental effects of active pharmaceutical compounds (APCs) in the environment are not well characterized, hence the need for comprehensive evaluation. This study employed three bioassays using three organisms, namely, Allium cepa, Daphnia magna, and Salmonella typhimurium, in the ecotoxicity study of lone and a mixture of selected APCs, namely, lamivudine (L), an antiretroviral, and ciprofloxacin (C) and sulfamethoxazole (S), antibiotics, at a concentration range between 10 and 100 ppb, in order to evaluate the potential of the lone and ternary mixture to exert synergistic toxicity. Study results from exposure to lone APCs showed that the L, C, and S trio individually had fatal impacts on daphnids, with mortality rates of 100, 75, and 95%, respectively, after 48 h. Sulfamethoxazole showed a mutagenic tendency, with a mutation ratio (background/sample ratio) of 2.0. Lamivudine showed a lethal impact on the root length of A. cepa (p > 0.05, p = 3.60E-3). Further microscopic examination of the A. cepa root tip revealed chromosomal aberrations on exposure to each compound. The LCS-mix ecotoxicology bioassays indicated a synergistic effect on the daphnids, probably due to potentiation. Although the LCS mix had a cytotoxic effect (evidenced by the absence of bacteria colonies) on exposed TA 98 P450 Salmonella typhimurium strain, this effect was not observed in other bacterial strains. Microscopic examination of A. cepa exposed to the LCS-mix revealed an aberration in the mitotic stage of the cell. The impact of combination of the pharmaceuticals in aqueous ecosystems was greater than when exposed to the tested individual pharmaceutical compounds. Study result showed that these compounds have tendencies to pose a higher risk to exposed living entities when in combined/potentiated forms, and this could lead to distortion of the regular functioning of the ecosystem, particularly bacterial and other microbial populations that are listed among primary producers of the aquatic food web.

Eco-corona formation diminishes the cytogenotoxicity of graphene oxide on Allium cepa: Role of soil extracted-extracellular polymeric substances in combating oxidative stress.

Graphene oxide (GO) is widely acknowledged for its exceptional biological and industrial applications. However, its discharge into the environment negatively impacts the ecosystem. This study aimed to investigate the toxicity of GO in Allium cepa root tip cells and the role of extracellular polymeric substances (EPS) in modulating its toxic effects. To evaluate toxicity, various endpoints like cell viability using Evans blue dye, cytotoxicity (mitotic index), genotoxicity (chromosomal aberrations), and oxidative stress assessments (total ROS, superoxide, hydroxyl radical production, and lipid peroxidation) were considered. The results suggest that pristine GO caused a dose-dependent increase in various toxicity parameters, especially the genotoxic effects. Oxidative stress generation by GO is proposed to be the principal mode of action. The EPS-corona formed on GO could potentially counteract the toxic effects, substantially reducing the oxidative stress within the cells.

In silico interactions and deep neural network modeling for toxicity profile of methyl methanesulfonate.

In this study, the toxicity induced by the alkylating agent methyl methanesulfonate (MMS) in Allium cepa L. was investigated. For this aim, bulbs were divided into 4 groups as control and application (100, 500 and 4000 µM MMS) and germinated for 72 h at 22-24 °C. At the end of the germination period root tips were collected and made ready for analysis by applying traditional preparation methods. Germination, root elongation, weight, mitotic index (MI) values, micronucleus (MN) and chromosomal abnormality (CAs) numbers, malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activities and anatomical structures of bulbs were used as indicators to determine toxicity. Moreover the extent of DNA fragmentation induced by MMS was determined by comet assay. To confirm the DNA fragmentation induced by MMS, the DNA-MMS interaction was examined with molecular docking. Correlation and principal component analyses (PCA) were performed to examine the relationship between all parameters and understand the underlying structure and relationships among these parameters. In the present study, a deep neural network (DNN) with two hidden layers implemented in Matlab has been developed for the comparison of the estimated data with the real data. The effect of MDA levels, SOD and CAT activities at 4 different endpoints resulting from administration of various concentrations of MMS, including MN, MI, CAs and DNA damage, was attempted to be estimated by DNN model. It is assumed that the predicted results are in close agreement with the actual data. The effectiveness of the model was evaluated using 4 different metrics, MAE, MAPE, RMSE and R2, which together show that the model performs commendably. As a result, the highest germination, root elongation, weight gain and MI were measured in the control group. MMS application caused a decrease in all physiological parameters and an increase in cytogenetic (except MI) and biochemical parameters. MMS application caused an increase in antioxidant enzyme levels (SOD and CAT) up to a concentration of 500 µM and a decrease at 4000 µM. MMS application induced different types of CAs and anatomical damages in root meristem cells. The results of the comet assay showed that the severity of DNA fragmentation increased with increasing MMS concentration. Molecular docking analysis showed a strong DNA-MMS interaction. The results of correlation and PCA revealed significant positive and negative interactions between the studied parameters and confirmed the interactions of these parameters with MMS. It has been shown that the DNN model developed in this study is a valuable resource for predicting genotoxicity due to oxidative stress and lipid peroxidation. In addition, this model has the potential to help evaluate the genotoxicity status of various chemical compounds. At the end of the study, it was concluded that MMS strongly supports a versatile toxicity in plant cells and the selected parameters are suitable indicators for determining this toxicity.

Phytotoxicity and cytogenotoxicity of pesticide mixtures: analysis of the effects of environmentally relevant concentrations on the aquatic environment.

In this study, we investigate the toxicity of commercial formulations based on glyphosate, 2,4-D, imidacloprid, and iprodione, in isolation and mixed, on Allium cepa. The mixtures consisted of combinations in the lowest (M1), intermediate (M2), and highest concentrations (M3) of each pesticide. We measured physiological (germination rate, germination speed, and radicular length) and cyto-genotoxic (mitotic index and frequency of aberrant cells) parameters. In addition, we analyzed the cell cycle progression and cell death induction by flow cytometry. When applied in isolation, the pesticides changed the parameters evaluated. M1 and M2 inhibited root length and increased the frequency of aberrant cells. Their genotoxic effect was equivalent to that of pesticides applied in isolation. Furthermore, M1 and M2 caused cell death and M2 changed the cell cycle progression. M3 had the greatest deleterious effect on A. cepa. This mixture inhibited root length and promoted an additive or synergistic effect on the mitotic index. In addition, M3 changed all parameters analyzed by flow cytometry. This research clearly demonstrates that the pesticides tested, and their mixtures, may pose a risk to non-target organisms.

DNA fragmentation, chromosomal aberrations, and multi-toxic effects induced by nickel and the modulation of Ni-induced damage by pomegranate seed extract in Allium cepa L.

This study was designed to assess the recovery effect of pomegranate seed extract (PSEx) against nickel (Ni)-induced damage in Allium cepa. Except for the control group treated with tap water, five experimental groups were exposed to 265 mg L-1 PSEx, 530 mg L-1 PSEx, 1 mg L-1 NiCI2, 265 mg L-1 PSEx + 1 mg L-1 NiCI2, and 530 mg L-1 PSEx + 1 mg L-1 NiCI2, respectively. The toxicity of Ni was examined through the analysis of physiological (germination percentage, weight gain, and root length), cytotoxicity (mitotic index), genotoxicity (micronucleus, chromosomal anomalies, and Comet test), and biochemical (malondialdehyde, proline, chlorophyll a and chlorophyll b contents, the activities of superoxide dismutase and catalase) parameters. Meristematic cell defects were also investigated. The NiCl2-DNA interaction was evaluated through spectral shift analysis. Values of all physiological parameters, mitotic index scores, and chlorophyll contents decreased while micronucleus frequency, DNA tail percentage, chromosomal anomalies, proline, MDA, and enzyme activities increased following Ni administration. According to the tail DNA percentage scale, Ni application caused "high damage" to DNA. Ni-induced chromosomal anomalies were fragment, sticky chromosome, vagrant chromosome, bridge, unbalanced chromatin distribution, reverse polarization, and nucleus with bud. NiCl2-DNA interaction caused a hyperchromic shift in the UV/Vis spectrum of DNA by spectral profile analysis. Ni exposure impaired root meristems as evidenced by the formation of epidermis cell damage, flattened cell nucleus, thickened cortex cell wall, and blurry vascular tissue. Substantial recovery was seen in all parameters with the co-administration of PSEx and Ni. Recovery effects in the parameters were 18-51% and 41-84% in the 265 mg L-1 PSEx + 1 mg L-1 NiCI2 and 530 mg L-1 PSEx + 1 mg L-1 NiCI2 groups, respectively. The Comet scale showed that PSEx applied with Ni reduced DNA damage from "high" to "moderate." Ni-induced thickened cortex cell wall and blurry vascular tissue damage disappeared completely when 530 mg L-1 PSEx was mixed with Ni. PSEx successfully reduced the negative effects of Ni, which can be attributed to its content of antioxidants and bioactive ingredients.

Toxicity of Heavy Metals that Affect Germination, Development and Cell Cycle of Allium cepa L.

This study aimed to investigate the impact of heavy metals copper, cadmium, lead, aluminum and nickel, on the growth, physiology, metabolism, and cell cycle of Allium cepa L. Five treatments with increasing concentrations (0, 50, 100, 250, and 500 µM) were applied to the seeds. The results showed that the highest concentrations of copper and cadmium had phytotoxic and biochemical effects on the onion. Additionally, copper concentrations caused an increase in mitodepressive effect and chromosomal abnormalities. Aluminum also induced several chromosomal abnormalities. The study found that Cd > Cu > Pb > Ni > Al and Cu > Al > Ni > Pb > Cd had the highest phytotoxic and cytotoxic potentials, respectively. Furthermore, the UPGMA method revealed three divergent groups. These results suggest that heavy metals, especially copper, have a significant pollution potential when present in high concentrations.

Protective effect of quercetin and thymoquinone against genotoxicity and oxidative stress induced by ZnO nanoparticles in the Wistar rat model.

Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in a variety of consumer and other commercial products. Hence, man faces the risk of exposure to ZnO-NPs and the consequent adverse health effects. Mitigation/prevention of such effects using natural products has drawn the attention of scientists. Therefore, the aim of the present study has been to find the toxic effects associated with exposure to ZnO-NPs, and the protective role of the phytochemicals thymoquinone (TQ) and quercetin (QCT) in the rat model. ZnO-NPs were administered to male Wistar rats through oral route; TQ / QCT was concurrently administered through intra-peritoneal route. The response in the animal was analyzed adopting chromosomal aberration test, micronucleus test, and comet assay of bone marrow cells to assess the genotoxicity, and biochemical assays of superoxide dismutase (SOD), catalase (CAT), lipid peroxidation (LPO), total extractable protein of liver, and reduced glutathione (GSH) of liver homogenate to monitor the changes in the antioxidant defense mechanism in response to the oxidative stress. Treatment of 300 mg/kg body weight (bw) of ZnO-NPs produced adverse effects on all aspects analyzed viz., structural chromosomal aberrations, micronuclei formation, DNA damage, SOD, catalase, lipid peroxidation, GSH, and extractable total protein of liver. Co-treatment of TQ / QCT offered protection against the toxicity induced by ZnO-NPs. The most optimum doses of TQ and QCT that offered the best protection were 18 mg/kg bw and 500 mg/kg bw, respectively. The study reveals that TQ / QCT supplementation is beneficial in the context of toxic effects of ZnO-NPs.

Genetic Counseling and Prenatal Diagnosis of a Maternally Inherited 15q11.2 Microduplication.

Unbalanced chromosome abnormalities (UBCA) are large genomic region variations that often result in minimal clinical effects. Copy number variants (CNVs), such as microdeletions and microduplications in 15q11.2, have been linked to various health issues, making prenatal diagnosis and genetic counselling challenging. Microdeletions and microduplications in the genomic region 15q11.2 are associated with congenital heart defects, autism, schizophrenia, epilepsy, mental retardation and developmental delay. The literature on this microduplication is confusing and extensive, which is a great difficulty for prenatal diagnosis and genetic counselling. A 35-year-old female undergoing amniocentesis at Week 19 due to advanced maternal age revealed a normal 46,XX karyotype through G-banding analysis. However, Chromosomal microarray analysis (CMA) on the same amniocytes detected a 550-Kb maternally inherited chromosomal microduplication in 15q11.2. An integrated approach combining karyotype analysis, CMA, genetic counseling, and prenatal ultrasound is crucial for the accurate prenatal diagnosis of UBCAs and CNVs.

Allium cepa tests: A plant-based tool for the early evaluation of toxicity and genotoxicity of newly synthetized antifungal molecules.

Many fungal genera such as Aspergillus, Penicillium, Fusarium and Alternaria are able to produce, among many other metabolites, the aflatoxins, a group of toxic and carcinogenic compounds. To reduce their formation, synthetic fungicides are used as an effective way of intervention. However, the extensive use of such molecules generates long-term residues into the food and the environment. The need of new antifungal molecules, with high specificity and low off-target toxicity is worth. The aim of this study was to evaluate: i) the toxicity and genotoxicity of newly synthesized molecules with a good anti-mycotoxic activity, and ii) the suitability of the Allium cepa multi-endpoint assay as an early screening method for chemicals. Eight compounds were tested for toxicity by using the A. cepa bulb root elongation test and for genotoxicity using the A. cepa bulb mitotic index, micronuclei and chromosome aberrations tests. Three molecules showed no toxicity, while two induced mild toxic effects in roots exposed to the highest dose (100 µM). A more pronounced toxic effect was caused by the other three compounds for which the EC50 was approximately 50 µM. Furthermore, all molecules showed a clear genotoxic activity, both in terms of chromosomal aberrations and micronuclei. Albeit the known good antifungal activity, the different molecules caused strong toxic and genotoxic effects. The results indicate the suitability of experiments with A. cepa as a research model for the evaluation of the toxic and genotoxic activities of new molecules in plants before they are released into the environment.

A gene-nutrient interaction between vitamin B6 and serine hydroxymethyltransferase (SHMT) affects genome integrity in Drosophila.

Pyridoxal 5'-phosphate (PLP), the catalytically active form of vitamin B6, participates as a cofactor to one carbon (1C) pathway that produces precursors for DNA metabolism. The concerted action of PLP-dependent serine hydroxymethyltransferase (SHMT) and thymidylate synthase (TS) leads to the biosynthesis of thymidylate (dTMP), which plays an essential function in DNA synthesis and repair. PLP deficiency causes chromosome aberrations (CABs) in Drosophila and human cells, rising the hypothesis that an altered 1C metabolism may be involved. To test this hypothesis, we used Drosophila as a model system and found, firstly, that in PLP deficient larvae SHMT activity is reduced by 40%. Second, we found that RNAi-induced SHMT depletion causes chromosome damage rescued by PLP supplementation and strongly exacerbated by PLP depletion. RNAi-induced TS depletion causes severe chromosome damage, but this is only slightly enhanced by PLP depletion. dTMP supplementation rescues CABs in both PLP-deficient and PLP-proficient SHMTRNAi . Altogether these data suggest that a reduction of SHMT activity caused by PLP deficiency contributes to chromosome damage by reducing dTMP biosynthesis. In addition, our work brings to light a gene-nutrient interaction between SHMT decreased activity and PLP deficiency impacting on genome stability that may be translated to humans.

DNA fragmentation and multifaceted toxicity induced by high-dose vanadium exposure determined by the bioindicator Allium test.

In this study, the toxicity of vanadium (VCI3) in Allium cepa L. was studied. Germination-related parameters, mitotic index (MI), catalase (CAT) activity, chromosomal abnormalities (CAs), malondialdehyde (MDA) level, micronucleus (MN) frequency and superoxide dismutase (SOD) activity were investigated. The effects of VCI3 exposure on the DNA of meristem cells were investigated with the help of comet assay, and the relationships between physiological, cytogenetic and biochemical parameters were revealed by correlation and PCA analyses. A. cepa bulbs were germinated with different concentrations of VCI3 for 72 h. As a result, the maximum germination (100%), root elongation (10.4 cm) and weight gain (6.85 g) were determined in the control. VCI3 treatment caused significant decreases in all tested germination-related parameters compared to the control. The highest percentage of MI (8.62%) was also observed in the control. No CAs were found in the control, except for a few sticky chromosomes and unequal distribution of chromatin (p > 0.05). VCI3 treatment caused significant decreases in MI and increases in the frequencies of CAs and MN, depending on the dose. Similarly, the comet assay showed that DNA damage scores increased with increasing VCI3 doses. The lowest root MDA (6.50 µM/g) level and SOD (36.7 U/mg) and CAT (0.82 OD240nmmin/g) activities were also measured in the control. VCI3 treatment caused significant increases in root MDA levels and antioxidant enzyme activities. Besides, VCI3 treatment induced anatomical damages such as flattened cell nucleus, epidermis cell damage, binuclear cell, thickening in the cortex cell wall, giant cell nucleus, damages in cortex cell and unclear vascular tissue. All examined parameters showed significant negative or positive correlations with each other. PCA analysis confirmed the relations of investigated parameters and VCI3 exposure.

A scoping review of recent advances in the application of comet assay to Allium cepa roots.

The comet assay is a sensitive method for the evaluation of DNA damages and DNA repair capacity at single-cell level. Allium cepa is a well-established plant model for toxicological studies. The aim of this scoping review was to investigate the recent application of the comet assay in Allium cepa root cells to assess the genotoxicity. To explore the literature a search was performed selecting articles published between January 2015 and February 2023 from Web of Science, PubMed, and Scopus databases using the combined search terms "Comet assay" and "Allium cepa". All the original articles that applied the comet assay to Allium cepa root cells were included. Of the 334 records initially found, 79 articles were identified as meeting the inclusion criteria. Some studies reported results for two or more toxicants. In these cases, the data for each toxicant were treated separately. Thus, the number of analyzed toxicants (such as chemicals, new materials, and environmental matrices) was higher than the number of selected papers and reached 90. The current use of the Allium-comet assay seems to be directed towards two types of approach: the direct study of the genotoxicity of compounds, mainly biocides (20% of analyzed compounds) and nano- and microparticles (17%), and assessing a treatment's ability to reduce or eliminate genotoxicity of known genotoxicants (19%). Although the genotoxicity identified by the Allium-comet assay is only one piece of a larger puzzle, this method could be considered a useful tool for screening the genotoxic potential of compounds released into the environment.

Clinical features and magnesium levels: Novel insights in 15q11.2 BP1-BP2 copy number variants.

BACKGROUND: Investigating copy number variations (CNVs) such as microdeletions or microduplications can significantly contribute to discover the aetiology of neurodevelopmental disorders. 15q11.2 genomic region, including NIPA1 and NIPA2 genes, contains a recurrent but rare CNV, flanked by the break points BP1 and BP2. Both BP1-BP2 microdeletion and microduplication have been associated with intellectual disability (ID), neuropsychiatric/behavioural disturbances and mild clinical features, even if with incomplete penetrance and variable expressivity. The pathogenic role of this CNV is quite unclear though. Unknown variants in other DNA regions and parent-of-origin effect (POE) are some of the mechanisms that have been proposed as an explanation of the wide phenotypic variability. As NIPA1 and NIPA2 encode for proteins that mediate magnesium (Mg2+ ) metabolism, it has been suggested that urinary Mg2+ levels could potentially represent informative and affordable biomarkers for a rapid screening of 15q11.2 duplications or deletions. Furthermore, magnesium supplementation has been proposed as possible therapeutic strategy. METHODS: Thirty one children with ID and/or other neurodevelopmental disorders carrying either a duplication or a deletion in 15q11.2 BP1-BP2 region have been recruited. When available, blood samples from parents have been analysed to identify the CNV origin. All participants underwent family and medical data collection, physical examination and neuropsychiatric assessment. Electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) scan were performed in 15 children. In addition, 11 families agreed to participate to the assessment of blood and urinary Mg2+ levels. RESULTS: We observed a highly variable phenotypic spectrum of developmental issues encompassing ID in most subjects as well as a variety of behavioural disorders such as autism and attention-deficit disorder/attention-deficit hyperactivity disorder. Dysmorphic traits and malformations were detected only in a minority of the participants, and no clear association with growth anomalies was found. Abnormal brain MRI and/or EEG were reported respectively in 64% and 92% of the subjects. Inheritance assessment highlighted an excess of duplication of maternal origin, while cardiac alterations were detected only in children with 15q11.2 CNV inherited from the father. We found great variability in Mg2+ urinary values, without correlation with 15q11.2 copy numbers. However, the variance of urinary Mg2+ levels largely increases in individuals with 15q11.2 deletion/duplication. CONCLUSIONS: This study provides further evidence that 15q11.2 BP1-BP2 CNV is associated with a broad spectrum of neurodevelopmental disorders and POE might be an explanation for clinical variability. However, some issues may question the real impact of 15q11.2 CNV on the phenotype in the carriers: DNA sequencing could be useful to exclude other pathogenic gene mutations. Our results do not support the possibility that urinary Mg2+ levels can be used as biomarkers to screen children with neurodevelopmental disorders for 15q11.2 duplication/deletion. However, there are evidences of correlations between 15q11.2 BP1-BP2 CNV and Mg2+ metabolism and future studies may pave the way to new therapeutic options.

Monitoring genotoxic, biochemical and morphotoxic potential of penoxsulam and the protective role of European blueberry (Vaccinium myrtillus L.) extract.

The present study aimed at exploring to explore the penoxsulam toxicity and protective effects of blueberry extract in roots of Allium cepa L. The effective concentration (EC50) of penoxsulam was determined at 20 µg/L by the root growth inhibition test as the concentration reducing the root length by 50%. The bulbs of A. cepa L. were treated with tap water, blueberry extracts (25 and 50 mg/L), penoxsulam (20 µg/L) and combination of blueberry extracts (25 and 50 mg/L) with penoxsulam (20 µg/L) for 96 h. The results revealed that penoxsulam exposure inhibited cell division, rooting percentage, growth rate, root length and weight gain in the roots of A. cepa L. In addition, it induced chromosomal anomalies such as sticky chromosome, fragment, unequal distribution of chromatin, bridge, vagrant chromosome and c-mitosis and DNA strand breaks. Further, penoxsulam treatment enhanced malondialdehyde content and SOD, CAT and GR antioxidant enzyme activities. Molecular docking results supported the up-regulation of antioxidant enzyme SOD, CAT and GR. Against all these toxicity, blueberry extracts reduced penoxsulam toxicity in a concentration-dependent manner. The highest amount of recovery for cytological, morphological and oxidative stress parameters was observed when using blueberry extract at a concentration of 50 mg/L. In addition, blueberry extracts application showed a positive correlation with weight gain, root length, mitotic index and rooting percentage whereas a negative correlation with micronucleus formation, DNA damage, chromosomal aberrations, antioxidant enzymes activities and lipid peroxidation indicating its protecting effects. As a result, it has been seen that the blueberry extract can tolerate all these toxic effects of penoxsulam depending on the concentration, and it has been understood that it is a good protective natural product against such chemical exposures.

Use of the Allium cepa Model to Assess the Cytogenotoxicity of Luffariella herdmani Marine Sponge Extract.

Marine sponge extracts are known to contain potentially toxic compounds that have biological activities of possible pharmacological interest. Thus, it is vital that biological models are used for the preliminary toxicity screening of such extracts. The present study reports the use of Allium cepa, a low-cost plant-based in vivo model, to assess the cytotoxicity and genotoxicity of Luffariella herdmani marine sponge crude extract (SCE). Pre-germinated onion bulbs, exposed for 96 hours to different concentrations of SCE (ranging from 0.3125 to 20 µg/ml), were used to determine general cytotoxicity. Root length as well as morphological abnormalities were recorded. Genotoxicity was assessed by exposing the root tips to SCE (0.3125-20 µg/ml) and the appropriate controls for 48 hours, and then staining with acetocarmine. The Mitotic Index (MI), Mitotic Phase Indices (MPIs) and chromosomal aberrations were evaluated and recorded. SCE inhibited A. cepa root growth (EC50 = 10.34 µg/ml) and elicited a mitodepressive effect (LC50 = 1.95 µg/ml) in a dose-dependent and significant manner. In addition, macroscopic alterations as well as chromosomal aberrations were detected. Overall, our findings indicate that L. herdmani crude extract exhibits cytotoxic and genotoxic activity, suggesting that it might contain substances with anti-proliferative/anticancer potential that could be subject to further characterisation.