Frequency Of Chromosomal Aberrations Research Articles

Vitamin B12 Protects Against Genotoxicity Induced by Cisplatin.

Cisplatin is an effective synthetic chemotherapeutic drug used for cancer treatment. Vitamin B12 has been shown to possess anti-genotoxic activity. This study aimed to investigate the effect of vitamin B12 on chromosomal damage induced by cisplatin. The level of sister chromatid exchanges (SCEs) and chromosomal aberrations (CAs) were measured in cultured human blood lymphocytes treated with cisplatin and/or vitamin B12. The results showed a significantly elevated frequency of CAs and SCEs of cisplatin-treated cultures compared to the control (P < 0.05). The CAs and SCEs induced by cisplatin were significantly lowered by pretreatment of cell cultures with vitamin B12. In addition, cisplatin caused a slight reduction in the mitotic index (MI), while vitamin B12 did not modulate the effect of cisplatin on MI. Vitamin B12 can protect human lymphocytes against genotoxicity associated with cisplatin.

Biological effects of radiation exposure in patients treated with X-ray guided endovascular aortic repair

Abstract Background X-ray guided cardiovascular interventions such as endovascular aortic repair (EVAR) expose patients and operators to significant amounts of repeated ionising radiation over a long period of time. The biological effect of such protracted radiation exposure is poorly understood. We have previously demonstrated a higher incidence of dicentric chromosome (DC) aberrations in high-volume endovascular interventionalists and differences in acute DNA damage in lymphocytes between individuals following in vitro irradiation. Studies suggested a higher incidence of cancer in patients who underwent EVAR compared with those who have had open aneurysm repair, but the evidence is inconclusive. Further work is required to evaluate the biological radiation risk of X-ray guided cardiovascular interventions. Purposes We aimed to examine radiation-induced genome instability from patients after complex EVAR. We also aimed to investigate the intrinsic response of each patient to radiation using biomarkers of acute DNA damage following in vitro irradiation of their blood and to correlate this response to the expression of radiation-responsive genes. Methods Lymphocytes were isolated from patients after complex (branched/fenestrated) EVAR and non-irradiated controls. DC, a type of chromosomal aberration caused by radiation exposure were enumerated. γ-H2AX, a marker of acute DNA damage/repair, was measured by immunofluorescence after in vitro irradiation at 0.2 Gy and 1 Gy, along with the expression of the radiation-responsive genes FDXR, CCNG1, P21 and PHPT1 using qPCR. Results 17 patients (82% male, median age 73[59 – 85years]) and 16 controls (56% male, median age 68[53 – 83years]) were recruited. The mean incidence of DC was 3.782 (95% CI 3.13 - 4.43) and 0.898 (95% CI 0.48 -1.32) per 1000 cells for patients and controls, respectively (P&amp;lt;0.0001). Patients had higher background of γ-H2AX foci than unexposed controls, (0.7056, 95% CI 0.316 - 1.10) vs (0.241 95% CI 0.077 - 0.405) per cell, P&amp;lt;0.05. FDXR expression was most increased following irradiation (P&amp;lt;0.0001), reaching a mean 13.1-fold and 11.4-fold increase at 4-hour and 24-hour time-point, respectively, but this upregulation was not significantly different between the two groups. Conclusion We have shown an increased frequency of chromosomal aberrations in patients after complex EVAR, a biological finding that may support a propensity to developing malignancies. Patients also have higher basal DNA damage/repair (γ-H2AX) activity. Expression of ferredoxin reductase, FDXR gene could be a potential radio-responsive biomarker to provide personalised biological dosimetry information for clinical monitoring. Our study further underlines the long-term radiation risk of X-ray guided cardiovascular interventions and the potential of biological assays that may guide personalised care.

Germline and somatic alterations in NBN and their putative impact on the pathogenesis of malignant neoplasms

Disruption of mechanisms that maintain genome stability is an essential factor of tumor progression. Accordingly, predisposition to the development of neoplasms is often associated with germline mutations in genes involved in DNA damage detection and repair. At the same time, impairment of DNA repair systems may be a predictor of antitumor treatment efficacy while overexpression of genes involved in DNA repair is a frequent event in various types of malignancies that can lead to development of tumor cells’ resistance to chemo- and radiotherapy. NBN (nibrin) gene encodes the subunit of the MRN complex which acts as a sensor of double-strand DNA breaks and participates in their repair by homologous recombination. Germline variants in NBN which are associated with increased risk of tumor development are generally represented by frameshift mutations that lead to the synthesis of truncated protein as well as by nonsense and some missense mutations which occur in functionally significant domains. These germline mutations result in partial loss of nibrin function and in increased frequency of spontaneous and induced chromosomal aberrations in the cells of the carriers. On the contrary, amplification of NBN locus is a predominant type of somatic mutations affecting this gene, which indicates a dual role of NBN protein in tumor progression. The results of several studies demonstrate the influence of NBN expression level and its mutational status on anti-tumor drug resistance in particular types of tumor cells and on the survival rate of patients. These data indicate that an in-depth study of different variants and their functional significance is necessary since NBN status may be essential for the choice of treatment tactics for some types of tumors.

DNA Damage, Cell Death, and Alteration of Cell Proliferation Insights Caused by Copper Oxide Nanoparticles Using a Plant-Based Model.

The speedy growth of copper oxide nanoparticle (CuO NP) manufacturing due to their wide application in industries has caused concerns due to their increased discharge into the environment from both purposeful and accidental sources. Their presence at an elevated concentration in the environment can cause potential hazards to the plant kingdom, specifically to staple food crops. However, limited research is available to determine the consequences of CuO NPs. The present study aimed to assess the morphological and cytological changes induced by CuO NPs on Pisum sativum L., a key staple food crop. Seeds of Pisum sativum were exposed to various concentrations of CuO NPs (0, 25, 50, 75, 100, and 125 ppm) for 2 h, and their effects on seed germination (SG), radicle length (RL), cell proliferation kinetics (CPK), mitotic index (MI), cell death (CD), micronucleus frequency (MNF), and chromosomal aberration frequency (CAF) were studied. The results indicate a significant reduction in SG, RL, CPK, and MI and a significant dose-dependent increase in CD, MNF, and CAF. CuO NP treatment has led to abnormal meiotic cell division, increased incidence of micronucleus frequency, and chromosomal aberration frequency. Additionally, the CuO NP-treated groups showed an increase in the percentage of aberrant meiotic cells such as laggard (LG), double bridge (DB), stickiness (STC), clumped nuclei (CNi), precocious separation (PS), single bridge (SB), and secondary association (SA). CuO NP treatment led to reductions in SG as follows: 55% at 24 h, 60.10% at 48 h, and 65% at 72 h; reductions in RL as follows: 0.55 ± 0.021 cm at 24 h, 0.67 ± 0.01 cm at 48 h, and 0.99 ± 0.02 cm at 72 h; reductions in CPK as follows: 34.98% at prophase, 7.90% at metaphase, 3.5% at anaphase, and 0.97% at telophase. It also led to a 57.45% increase in CD, a 39.87% reduction in MI, and a 60.77% increase in MNF at a higher concentration of 125 ppm. The findings of this study clearly show that CuO NPs have a genotoxic effect on the food crop plant Pisum sativum.

Chromosomal aberrations and early mortality in a non-mammalian vertebrate: example from pressure-induced triploid Atlantic salmon.

In commercial aquaculture, the production of triploid fish is currently the most practical approach to prevent maturation and farm-to-wild introgression following escapes. However, triploids often exhibit poor welfare, and the underlying mechanisms remain unclear. Inheritance issues associated with sub-optimal hydrostatic pressure treatments used to induce triploidy, or the genetic background of parental fish, have been speculated to contribute. We tested this by quantifying the frequency and type of chromosomal aberrations in Atlantic salmon subjected to a gradient of sub-optimal pressure treatments (Experiment 1) and from multiple mothers (Experiment 2). From these experiments, we genotyped a subsample of ~900 eyed eggs and all ~3300 surviving parr across ~20 microsatellites. In contrast to the low frequency of chromosomal aberrations in the diploid (no hydrostatic pressure) and triploid (full 9500 PSI treatment) controls, eyed eggs subjected to sub-optimal pressure treatments (6500-8500 PSI) had a higher incidence of chromosomal aberrations such as aneuploidy and uniparental disomy, corresponding to lower triploidization success and higher egg mortality rates. We also observed maternal effects on triploidization success and incidence of chromosomal aberrations, with certain half-sibling families exhibiting more aberrations than others. Chromosomal aberrations were rare among surviving parr, suggesting a purge of maladapted individuals during early development. This study demonstrates that sub-optimal hydrostatic pressure treatments and maternal effects not only influence the success of triploidization treatments, but may also affect the incidence of chromosomal aberrations and early mortality. The results have important implications for aquaculture breeding programs and their efforts to prevent farm-to-wild introgression.

Array Comparative Genomic Hybridization (aCGH) Results among Patients Referred to Invasive Prenatal Testing after First-Trimester Screening: A Comprehensive Cohort Study.

Introduction: Invasive prenatal testing with chromosomal microarray analysis after first-trimester screening is a relevant option but there is still debate regarding the indications. Therefore, we evaluated the prevalence of numerical chromosomal aberrations detected by classic karyotype and clinically relevant copy number variants (CNVs) in prenatal samples using array comparative genomic hybridization (aCGH) stratified to NT thickness: <the 95th percentile, the 95th percentile-2.9 mm, 3.0-3.4 mm, 3.5-3.9 mm, 4.0-4.5 mm, and >4.5 mm, and by the presence/absence of associated structural anomalies detected by ultrasonography. Materials and Methods: Retrospective cohort study carried out at two tertiary Polish centers for prenatal diagnosis (national healthcare system) in central and south regions from January 2018 to December 2021. A total of 1746 prenatal samples were received. Indications for invasive prenatal testing included high risk of Down syndrome in the first-trimester combined test (n = 1484) and advanced maternal age (n = 69), and, in 193 cases, other reasons, such as parental request, family history of congenital defects, and genetic mutation carrier, were given. DNA was extracted directly from amniotic fluid (n = 1582) cells and chorionic villus samples (n = 164), and examined with classic karyotype and aCGH. Results: Of the entire cohort of 1746 fetuses, classical karyotype revealed numerical chromosomal aberrations in 334 fetuses (19.1%), and aCGH detected CNV in 5% (n = 87). The frequency of numerical chromosomal aberrations increased with NT thickness from 5.9% for fetuses with NT < p95th to 43.3% for those with NT > 4.5 mm. The highest rate of numerical aberrations was observed in fetuses with NT > 4.5 mm having at least one structural anomaly (50.2%). CNVs stratified by NT thickness were detected in 2.9%, 2.9%, 3.5%, 4.3%, 12.2%, and 9.0% of fetuses with NT < 95th percentile, 95th percentile-2.9 mm, 3.0-3.4 mm, 3.5-3.9 mm, 4.0-4.5 mm, and >4.5 mm, respectively. After exclusion of fetuses with structural anomalies and numerical aberrations, aCGH revealed CNVs in 2.0% of fetuses with NT < 95th percentile, 1.5% with NTp95-2.9 mm, 1.3% with NT 3.0-3.4 mm, 5.4% with NT 3.5-3.9 mm, 19.0% with NT 4.0-4.5 mm, and 14.8% with NT > 4.5 mm. Conclusions: In conclusion, our study indicates that performing aCGH in samples referred to invasive prenatal testing after first-trimester screening provides additional clinically valuable information over conventional karyotyping, even in cases with normal NT and anatomy.

Trends in the cytogenetic and immunologic status of healthy persons; Kazakhstan, 2007–2022

Environmental pollution can affect immune health and genome stability. We have studied the immunological and cytogenetic status of healthy urban (Almaty City, which has high levels of air pollution) and rural residents of southern Kazakhstan, over the past 15 years. Differences between the groups in plasma immunoglobulin levels and chromosomal aberration frequencies were noted. Over the 15-year study period, decreases of immunoglobulin levels and increases of chromosomal aberration frequencies were observed and correlated with place of residence and ecological status of the region of residence; both ecological deterioration and the coronavirus pandemic are likely to have had negative effects.

Frequencies of chromosomal aberrations and related biochemical parameters in welders

Stainless steel welders are exposed to heavy filler metals. We evaluated the concentration of these metals in whole blood and urine, and the relevant biochemical parameters in relation to the total chromosomal aberrations (CAs), chromatid-type (CTA-type, CTAs) and chromosome-type (CSA-type, CSAs), in 117 welders and control individuals. Statistically higher concentrations of the total Cr, Ni and Mn were observed in whole blood and urine of welders, and the concentrations were higher in welders who smoked. On the contrary, concentrations of urinary heavy metals Cr and Mn adjusted for creatinine were significantly higher in the control groups. A statistically higher frequency of total CAs was observed in the whole group of welders, and also in the non-smoking welders, as compared to controls. The frequency of total CAs significantly correlated with the concentration of Cr, Ni and Mn in whole blood (R=0.61, P˂0.0001, R=0.33, P˂0.0001 and R=0.66, P˂0.0001, respectively), with urinary concentrations of Ni and Mn (R=0.27, P=0.003 and R=0.28, P=0.003, respectively) and with urinary concentrations of Cr, Ni and Mn adjusted for creatinine (R=0.22, P=0.029, R=0.26, P=0.005 and R=0.20, P=0.030, respectively). Likewise, the frequency of CTA-types significantly correlated with the concentration of Cr and Mn in whole blood (R=0.31, P=0.0007 and R=0.34, P=0.0002). The frequency of CSA-types significantly correlated with concentrations of Cr, Ni and Mn in whole blood (R=0.43, P˂0.0001, R=0.38, P˂0.0001 and R=0.46, P˂0.0001, respectively). The statistically higher values of serum creatinine and total bilirubin were detected in all welders, as well as in smokers when compared to the corresponding controls. The exposure to heavy metals in welders increased the frequencies of CAs and altered the balance between urinary excretion of heavy metals and their possible accumulation.

Cytogenetic monitoring of spontaneous mutagenesis

Due to the challenging environmental situation in Ukraine, there is a need for cytogenetic monitoring, establishing cause-and-effect relationships, and assessing the toxic-mutagenic activity of environmental components. The results of such monitoring can serve as a basis for developing rehabilitation measures aimed at improving the environmental condition. Cytogenetic bioassay methods allow the evaluation of ecological and genetic risks to biota, considering the overall impact of pollutants, predicting changes in ecosystems, and making timely management decisions to improve environmental quality and preserve the nation’s gene pool. The article provides cytogenetic monitoring of apical meristems of the roots of Raphanus sativus subsp. radicula (Pers.) DC. and Allium cepa L. seedlings., grown on soils of residential areas, and the effect of ions of some elements on the cytological parameters of Pisum sativum L. was studied. It was noted that the spectrum of mitosis abnormalities and chromosome aberrations was expanded due to lagging chromosomes and micronuclei. Residential areas with a consistently high level of spontaneous cytogenetic disorders require the development of a local monitoring system to identify genetic hazards. The research on the proliferative activity of apical meristem cells confirms the hypothesis of aluminum toxicity to plants. Cytotoxic effects are assessed at the micro- and macroscopic levels. Macroscopically, reduced root growth of bioindicator plants was observed, which may result from several possible mechanisms: cell death, inhibition of division, cell elongation, or nutrient absorption. It was found that the duration of the prophase is directly influenced by the mobile forms of Zn and Pb, while Cu has a reverse effect. According to the results of multiple regression analysis, the most significant influence on these processes is exerted by the mobile forms of Zn, Cu, and Pb in the surface layers of the soils of the studied residential areas. Under the influence of AlCl3, the proportion of cells in the anaphase stage increases; CdCl2 affects the prophase stage; Na2SeO3 affects the meta- and anaphase stages; X-ray irradiation affects the telophase stage. Regarding the ability to induce the frequency of aberrant anaphases, a ranking can be constructed: Na2SeO3 (3.75·10–6 M) &gt; AlCl3 (3.86·10–5 M) &gt; CdCl2 (8.44·10–5 M). A radiation dose of 9.03·10–3 C/kg leads to the frequency of chromosomal aberrations, similar to the effects of AlCl3 (3.86·10–4 M) and Na2SeO3 (8.34·10–6 M). High concentrations of aluminum are associated with an increase in anaphases with fragments and two to three bridges.

Conversion from the frequency of chromosome translocations in T-lymphocytes to the bone marrow dose in the long-term period after internal 89,90 Sr exposure

Cytogenetic Fluorescence In Situ Hybridization studies, that allow assessing the frequency of stable chromosome aberrations in circulating T lymphocytes, are commonly used in retrospective dosimetry in cases of uniform whole-body exposure. In the event of 89,90Sr exposure, interpretation of cytogenetic data is challenging, especially if blood sampling occurs long after the start of exposure. The weighted average dose to T-lymphocytes at the time of donor blood sampling in the long-term period after exposure to 89,90Sr does not coincide with the red bone marrow dose. Previously, we developed a model that allows us to estimate the weighted average doses to T-lymphocytes upon 89,90Sr ingress into the body of people belonging to various age groups. In this study, the modeling results were used to estimate the conversion factors from the frequency of translocations to the red bone marrow dose, which is important for assessing radiobiological effects associated with hematological diseases. The objective of our study is to estimate numerically the conversion factors (Brbm) from the dose to lymphocytes to the dose to red bone marrow for various scenarios of 89,90Sr ingestion depending on age, sex, and time after the start of exposure. The following scenarios are considered: single, uniform chronic for six months, uniform chronic for 1-5 years, non-uniform intake for 5 years (simulates the dynamics of intake in the Techa riverside settlements in 1950-1954). As a result, it has been found that the Brbm values significantly depend on the age at the time of 89,90Sr intake. The older the person is at the start of exposure, the more the cytogenetic dose differs (it is significantly lower) from the dose to the red bone marrow. We can say that the cytogenetic dose corresponds to the red bone marrow dose only in newborns and infants. This is due to the age-related dynamics of T-cell populations. Sex does not have a significant effect on Brbm. The effect of the 89,90Sr intake duration on Brbm is the most pronounced for 15-year-old adolescents. For them, the difference in Brbm values for a single and chronic 5-year ingress reaches 13%. Non-uniform intake of 90Sr over several years does not have a significant effect on Brbm and can be modelled by a uniform intake of the same duration.

P-355 Effect of biphasic CAPA-IVM on ovarian tissue oocytes of transgender men

Abstract Study question Can CAPA-IVM (Biphasic in-vitro maturation) with C-type natriuretic peptide (CNP), followed by in vitro maturation (IVM) improve ovarian tissue oocyte (OTO) maturation in transgender patients? Summary answer CAPA-IVM did not show any significant difference in maturation competence and frequency of chromosomal aberrations when compared with standard and in-house IVM. What is known already OTO-IVM is a method of fertility preservation in patients where prior ovarian stimulation is undesired. It has resulted in live births in cancer and polycystic ovarian syndrome (PCOS) patients. CAPA-IVM has further improved oocyte competency in these patients by synchronizing nuclear and cytoplasmic maturity. Similarly, OTO can be collected from transgender men without ovarian stimulation during gender reassignment surgery. While oocytes do survive and mature, OTO-IVM in transgender men is characterized by decreased fertilization rate and severely compromised developmental competency. We investigated whether CAPA-IVM can improve cytoplasmic immaturity for transgender OTO. Study design, size, duration Patients were recruited from July 2022 to July 2023. Both ovaries were collected from 9 transgender patients (age= 20-24 years, mean age=22 years) who underwent gender reassignment surgery after testosterone treatment (mean length= 34 months). All ovaries were collected in cold medium (4oC) and manipulation was performed within 30 minutes of the collection for the retrieval of cumulus oocyte complexes (COCs). Participants/materials, setting, methods Collected COCs were cultured either in in-house IVM and Standard (Medicult) IVM medium for 48 hours or in biphasic CAPA-IVM for 54 hours (24 hours pre-maturation culture and 30 hours IVM). Following maturation, oocytes were analyzed for calcium (Ca2+)-releasing potential and developmental competency after ICSI. In vitro matured MI (metaphase I) oocytes from stimulated IVF patients served as controls. Genetic analysis was performed on subsequent embryos to detect chromosomal abnormalities in all groups. Main results and the role of chance After culturing 330 COCs, the survival rate following maturation was similar in the in-house IVM (79%) compared to Medicult (72%, p = 0.221) and CAPA-IVM (73%, p = 0.251). A similar maturation rate (i.e. 55-57%) was observed in the different groups. Following ICSI, 15/25 (60%) CAPA-IVM, 13/19 (68.5%) Medicult IVM, and 17/28 (61%) in-house IVM oocytes were normally fertilized, which was lower than controls (24/29, 83%). Blastocyst rate was inferior in all OTO groups and significantly lower (p = 0.031) in Medicult-IVM (0/13) compared to controls (7/24). Ca2+-releasing potential of oocytes was determined as a product of amplitude and frequency, in arbitrary units (AU). The average values for CAPA-IVM (1.74AU), Medicult IVM (1.24AU), and in-house IVM (1.54AU) were significantly lower (p = 0.022, p = 0.008 and p = 0.017 respectively) compared to controls (4.76AU). Shallow whole genome sequencing of developed embryos (Day 2- Day 5) showed that 8/13 (61.5%) in CAPA-IVM, 4/8 (50%) in In-house IVM, 1/6 (17%) in Medicult, and 4/12 (33%) in the Control group were chromosomally normal. Limitations, reasons for caution The limited inclusion of patients warrants caution in the interpretation of the results. Moreover, the lack of a better control group might mask the properties of OTO-IVM. Wider implications of the findings Our preliminary results do not demonstrate an improvement in oocyte maturation and embryo development with the implementation of CAPA-IVM. However, future proteomics and transcriptomic studies would shed more light on the advantages of the current IVM systems and decipher the true potential of OTO-IVM from transgender men. Trial registration number not applicable

Approach regarding the biosafety evaluation of black and red currant pomace extracts using Allium cepa test

Abstract In the present work, biosafety evaluation of black and red currant pomace extracts was conducted using in vivo plant test system, such as Allium cepa, a sustainable method which can provide valuable information on the cytotoxic and genotoxic effect of extracts from natural sources in relation with their phytochemical composition. In this view, different aqueous and hydroethanolic extractions from black and red currant pomaces were carried out. For revealing the differences in the phytochemical profile of the studied extracts, rapid, efficient and easy-to-operate analytical techniques such as colorimetry, UV-Vis spectrometry and electrometry were used. Cytogenetic analysis of pomace extracts was achieved using Allium cepa test by scoring the mitotic index, the limit value of cytotoxicity, the phase index of mitosis and presence of chromosomal aberrations for all samples and comparing to the control (tap water). The results have shown that the cytogenetic response depends both on the type of pomaces and on the experimental extraction conditions. Compared to the control sample (22.58 %), a decrease in mitotic index for each analyzed sample was observed. As well, an increase in the cells with chromosomal aberrations was detected in onion root tips exposed to the tested extracts compared to the control (0.69 %). The lowest value of mitotic index (12.44 %) and the highest value of chromosomal aberrations (1.91 %) were recorded from the root tip cells of onion bulbs exposed to the hydroalcoholic extract obtained from red currants pomace using water/ethanol (60:40 v/v). Even if the mitotic index decreased, the limit value of cytotoxicity was higher than 50 %, level considered as a sublethal condition for the organisms. At the same time, the increase of the frequency of chromosomal aberrations is not so significant, and in correlation with the cytotoxicity limit, it does not indicate a genotoxic effect on onion cells. Following these results, it can be concluded that black and red currant pomace extracts can be safely used for possible therapeutic benefits.

Evaluation with physiological, cytogenetic, biochemical and anatomical aspects of dose-dependent inhibitory activity of jasmonic acid, a lipidderived growth regulator, in onion root tip cells

The effects of different doses of exogenous jasmonic acid (JA), were investigated on physiological parameters such as germination percentage, root length, root number and fresh weight, cytogenetic parameters such as mitotic index (MI), micronucleus (MN), frequency and chromosome aberration (CA), biochemical parameters as such superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and proline (PR) contents of Allium cepa L., known as onion. In addition, the changes in the root anatomical structures of the bulbs were examined under the microscope by taking cross-sections. Onion bulbs were divided into four groups as one control (C) and three treatments. The bulbs of the C group were kept in cuvettes containing tap water for 7 days and the bulbs of the treatment groups were kept in cuvettes containing 100 µM, 250 µM and 500 µM JA. JA administration caused a decrease in all physiological parameters examined, an increase in the frequency of MN and CA, and a reduce in MI compared to group C. In addition, the mentioned application caused a dosedependent increase in CAT and SOD activities and MDA and PR contents compared to group C. Moreover, 500 µM JA, the highest application dose, caused quite significant damages such as giant cell nucleus, unclear vascular tissue, binuclealar cell and accumulation of some substances in the cells of the epidermis/cortex in root anatomical structure of the bulbs. In summary, it was concluded that JA is a chemical with inhibitory functions and the Allium cepa test is a useful bioindicator for monitoring these effects.

Lanthanum nitrate demonstrated no genotoxicity in the conducted tests

Given the widespread applications in industrial and agricultural production, the health effects of rare earth elements (REEs) have garnered public attention, and the genotoxicity of REEs remains unclear. In this study, we evaluated the genetic effects of lanthanum nitrate, a typical representative of REEs, with guideline-compliant in vivo and in vitro methods. Genotoxicity assays, including the Ames test, comet assay, mice bone marrow erythrocyte micronucleus test, spermatogonial chromosomal aberration test, and sperm malformation assay were conducted to assess mutagenicity, chromosomal damage, DNA damage, and sperm malformation. In the Ames test, no statistically significant increase in bacterial reverse mutation frequencies was found as compared with the negative control. Mice exposed to lanthanum nitrate did not exhibit a statistically significant increase in bone marrow erythrocyte micronucleus frequencies, spermatogonial chromosomal aberration frequencies, or sperm malformation frequencies compared to the negative control (P > 0.05). Additionally, after a 24-h treatment with lanthanum nitrate at concentrations of 1.25, 5, and 20 μg/ml, no cytotoxicity was observed in CHL cells. Furthermore, the comet assay results indicate no significant DNA damage was observed even after exposure to high doses of lanthanum nitrate (20 μg/ml). In conclusion, our findings suggest that lanthanum nitrate does not exhibit genotoxicity.

A comprehensive analysis of royal jelly protection against cypermethrin-induced toxicity in the model organism Allium cepa L., employing spectral shift and molecular docking approaches

In this study, the toxicity of the pesticide cypermethrin and the protective properties of royal jelly against this toxicity were investigated using Allium cepa L., a model organism. Toxicity was evaluated using 6 mg/L cypermethrin, while royal jelly (250 mg/L and 500 mg/L) was used in combination with cypermethrin to test the protective effect. To comprehend toxicity and protective impact, growth, genotoxicity, biochemical, comet assay and anatomical parameters were employed. Royal jelly had no harmful effects when applied alone. On the other hand, following exposure to cypermethrin, there was a reduction in weight increase, root elongation, rooting percentage, mitotic index (MI), and chlorophyll a and b. Cypermethrin elevated the frequencies of micronucleus (MN) and chromosomal aberrations (CAs), levels of proline and malondialdehyde (MDA), and the activity rates of the enzymes catalase (CAT) and superoxide dismutase (SOD). A spectral change in the DNA spectrum indicated that the interaction of cypermethrin with DNA was one of the reasons for its genotoxicity, and molecular docking investigations suggested that tubulins, histones, and topoisomerases might also interact with this pesticide. Cypermethrin also triggered some critical meristematic cell damage in the root tissue. At the same time, DNA tail results obtained from the comet assay revealed that cypermethrin caused DNA fragmentation. When royal jelly was applied together with cypermethrin, all negatively affected parameters due to the toxicity of cypermethrin were substantially restored. However, even at the maximum studied dose of 500 mg/L of royal jelly, this restoration did not reach the levels of the control group. Thus, the toxicity of cypermethrin and the protective function of royal jelly against this toxicity in A. cepa, the model organism studied, were determined by using many different approaches. Royal jelly is a reliable, well-known and easily accessible protective functional food candidate against the harmful effects of hazardous substances such as pesticides.

Model of age-dependent dynamics and biokinetics of T-cells as natural biodosimeters.

Circulating T-lymphocytes are used as "natural biodosimeters" for estimating radiation doses, since the frequency of chromosomal aberrations induced in them is proportional to the accumulated dose. Moreover, stable chromosomal aberrations (translocations) are detected years and decades after exposure. Internal incorporation of radionuclides often leads to non-uniform exposure, which resulted in difficulties in the application of retrospective biodosimetry using T-lymphocytes. Some properties of T-lymphocytes complicate retrospective biodosimetry in this case: (1) the thymic production of T-cells depends significantly on age, the maximum is observed in early childhood; (2) the "lymphocyte-dosimeter" accumulates changes (translocations) while circulating through the body. The objective of this paper is to describe the technical characteristics of the model of age dynamics and T-cell biokinetics and approaches to assessing the dose to circulating lymphocytes under various exposure scenarios. The model allows to quantify the fractions of T-lymphocytes that were formed before and after exposure. The model takes into account the time fractions that circulating lymphocytes spend in various lymphoid organs. Age-related thymic involution was also considered. The model predicts that after internal exposure to 90Sr, the doses to T-lymphocytes can differ significantly from the doses to the bone marrow and other tissues. For uniform external γ-exposure, and for internal exposure due to non-bone -seeking radionuclides (for example, 144Ce), predicted doses to T-lymphocytes are very close to bone marrow doses. The model allows to quantify the correction factors for FISH-based doses to obtain doses to organs and tissues.

Genotoxicity detected during cyanobacteria bloom in a water supply reservoir

The aquatic ecosystems are susceptible to cyanobacterial blooms due to the eutrophication of water bodies caused by human activities. In this study, phytoplankton and cyanotoxins analysis, as well as cellular and genetic biomarkers of toxicity (Allium cepa test - higher plant test system), were evaluated in water samples of Alagados Reservoir during a cyanobacterial bloom in South Brazil. The water samples were collected during the wet season at two sites in the Reservoir. Paralytic shellfish toxins (PSTs) were detected in both samples (sites 1 and 2); however, the levels of PSTs were higher in site 1. Gonyautoxin 2 was the major cyanotoxin found in the Reservoir. Both samples were able to induce cytotoxic effects (reduced Mitotic Index) and damage the genetic material (i.e., increased frequencies of chromosome aberration and micronuclei) of meristematic cells of A. cepa. The cellular and genetic damages were higher in the sample site 1, wherein high levels of PSTs were verified. Thus, our findings suggested that cyanotoxins-contaminated waters may damage the genetic material of living organisms, and therefore this group of contaminants should be assessed for their potential genotoxicity.

Protective Effect of Boric Acid Against Ochratoxin A-Induced Toxic Effects in Human Embryonal Kidney Cells (HEK293): A Study on Cytotoxic, Genotoxic, Oxidative, and Apoptotic Effects.

The present study evaluates the protective properties of boric acid (BA) against the toxic effects induced by ochratoxin A (OTA) in human embryonic kidney cells (HEK293). The focus is on various parameters such as cytotoxicity, genotoxicity, oxidative stress, and apoptosis. OTA is a known mycotoxin that has harmful effects on the liver, kidneys, brain, and nervous system. BA, on the other hand, a boron-based compound, is known for its potential as a vital micronutrient with important cellular functions. The results show that BA administration not only increases cell viability but also mitigates the cytotoxic effects of OTA. This is evidenced by a reduction in the release of lactate dehydrogenase (LDH), indicating less damage to cell membranes. In addition, BA shows efficacy in reducing genotoxic effects, as the frequency of micronucleus (MN) and chromosomal aberrations (CA) decreases significantly, suggesting a protective role against DNA damage. In addition, the study shows that treatment with BA leads to a decrease in oxidative stress markers, highlighting its potential as a therapeutic intervention against the deleterious effects of OTA. These results emphasize the need for further research into the protective mechanisms of boron, particularly BA, in combating cell damage caused by OTA.

Chromosomal disorders in Triticum aestivum subject to prolonged radionuclide pollution of soil from the Exclusion Zone of the Chornobyl Nuclear Power Plant

Due to the large number of nuclear power plants around the globe and the growing threat of radioactive accidents, a complex assessment of the biological consequences of the Chornobyl disaster is a relevant issue. Study of mutagenic activity of prolonged and chronic action of radionuclide pollution of soil in the Chornobyl Exclusion Zone long after the accident will allow us to identify the current level of threat they pose to the human genome and can reveal specific cytogenic markers of radionuclide environmental pollution. For this purpose, we germinated seeds of wheat of soft winter varieties Smuhlianka and Bohdana in soil samples from the Chornobyl Exclusion Zone 35 years after the disaster. Specific activity of Cs-137 and Sr-90 accounted for 4.5–28.2 kBq/kg. To determine the frequency and range of chromosomal aberrations, we used the anaphase-telophase method. In aberrant cells, we studied extracellular distribution of chromosomal disorders. The frequency of aberrant cells was 3.53–7.55 times above the spontaneous level. High mutagenic activity remained in the conditions of the lowest density of radionuclide pollution of soil. The range of chromosomal disorders mostly included paired fragments and bridges and containd chromosomal acentric rings, binding of chromosomes, myocardium, and lagging and leading chromosomes. Radionuclide pollution in the Chornobyl Exclusion Zone induced multiple cellular aberrations in the rhizome meristem, the share of which was the highest in case of low specific radionuclide pollution of soil, and exhibited a tendency towards decrease against the background of the highest density of radionuclides. Pollution of the environment with radionuclides as a result of disasters at nuclear energy objects poses a threat to the human genome and is a global problem, requiring state support to solve through systematic genetic monitoring in readionuclide-polluted territories and areas adjacent to them.

Influence of Sayanogorsk Aluminum Plant emissions on morphological characteristics and phytopathology of Scots pine (&lt;i&gt;Pinus sylvestris&lt;/i&gt; L., 1753)

This article presents data on the variability of morphological features and cytogenetic indicators in Scots Pine (Pinus sylvestris) growing in areas affected by the industrial activity of the Sayanogorsk Aluminum Plant (SAP). We demonstrated that in polluted plots located at a distance of 1 and 5 km from the plant, the reproductive organ indicators of pine significantly decreased, germination energy and viability decreased, and needle necrosis frequency increased compared with the control. A significant increase in the frequency of class III needle necrosis in experimental plots by 7.2–8.6 times compared with the control, as well as a decrease in germination energy and seed germination in experimental plots by 1.1 and 1.3–1.5 times indicates the strong negative impact of SAP emissions on pine. Mitotic index and frequency of chromosomal aberrations in the apical meristem cells of Scots Pine seedlings were determined by cytogenetic analysis. A considerable reduction in mitotic activity by 1.35 to 0.8 times was observed in the meristem cells of Scots Pine growing in experimental plots, compared with the control plot. A tendency toward an increase in the frequency of abnormal mitoses of Scots Pine in the experimental areas was observed. Thus, the data obtained made it possible to assess the condition of Scots Pine in areas exposed to the influence of SAP.