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Povzetek: Bisphenols (BPs) are industrial chemicals extensively used in polycarbonate plastics and epoxy resins for everyday products, including food and beverage containers, toys, and thermal paper, representing major sources of human exposure. Bisphenol A (BPA) is the most prevalent; however, due to its endocrine-disrupting, reproductive, and genotoxic effects, it is classified as a substance of high concern by the European Chemicals Agency. Regulatory restrictions have prompted the use of structural analogues, including bisphenol AP (BPAP) and bisphenol C (BPC); however, emerging evidence suggests they may pose similar or greater health risks. Comprehensive data on their toxicity and human exposure, especially in mixtures, remain limited. This study assessed the cytotoxic and genotoxic effects of BPA, and less studied analogues BPAP, BPC, and their binary mixtures using a human-relevant 3D HepG2 spheroid model, representing an advanced in vitro system. Spheroids were exposed for 24 and 96 h, and effects were evaluated by ATP-based viability assays, comet assay, and targeted transcriptomics. None of the bisphenols induced significant cytotoxicity, although slight reductions in viability were observed for BPAP, BPC, and mixtures. DNA strand breaks were detected after exposure to BPA, BPC, and mixtures. Transcriptomic analysis revealed modest stress responses and strong upregulation of xenobiotic metabolism genes (CYP1A1, CYP1A2, CYP3A4, UGT1A1, NAT2), indicating cellular recognition of the tested bisphenols as bioactive xenobiotics. Antioxidant and DNA repair genes were largely unchanged, except for upregulation of oxidative stress markers HMOX1 and SRXN1 and a slight increase in OGG1, indicating oxidative DNA damage. Importantly, mixture effects were predominantly additive, with no evidence of synergistic interactions under the tested conditions. Overall, bisphenol exposure primarily triggered oxidative stress and metabolic responses rather than robust DNA damage signalling, suggesting that genotoxicity is largely mediated by reactive oxygen species. By integrating multiple endpoints in a 3D liver model, this study provides a more comprehensive assessment of bisphenol toxicity and highlights potential risks associated with BPA analogues and their mixtures, supporting the need for a comprehensive safety assessment to evaluate their suitability as replacements in consumer products.
Ključne besede: bisphenol, DNA damage, oxidative stress, complex mixtures, metabolism
Objavljeno v DiRROS: 10.07.2026; Ogledov: 167; Prenosov: 178
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Povzetek: Ypsolopha chazariella (Mann, 1866) (Lepidoptera: Ypsolophidae) is a European moth species known to feed on Tatar maple (Acer tataricum L.), a tree species naturally present in Europe. In 2009–2023, characteristic damage provisionally attributed to Y. chazariella was documented in botanical gardens in Novosibirsk, Krasnoyarsk (Russia, Siberia), suggesting the occurrence of a new pest. In 2024, significant damage was observed in an arboretum in Krasnoyarsk (Eastern Siberia) on the introduced A. tataricum and East Asian Acer ginnala Maxim. Two adult specimens of Y. chazariella were reared from larvae collected on both maple hosts and identified using genital morphology. Seven DNA barcodes (mitochondrial COI gene fragments) obtained for the specimens from Krasnoyarsk (6 specimens) and Novosibirsk (1) analyzed together with available DNA barcodes from Belarus and Finland showed low intraspecific divergence (0.7%). Among six haplotypes detected, two of them were formed solely by the Siberian specimens connected with the haplotypes recorded in Europe through two mutation steps. Genetic distance analyses revealed clear differentiation from closely related species (Y. dorsimaculella, Y. arizonella, and Y. rubrella) in the Barcode of Life Database (BOLD), with pairwise minimal distances between Y. chazariella and above-mentioned species ranging from 10.6% to 12.9%. A brief species essay was compiled, providing a note on the species biology, molecular genetics, present species range, and impact in ornamental plantings. Photographic documentation includes characteristic feeding damage and images of adult moths, along with detailed illustrations of male and female genitalia.
Ključne besede: alien pest, moth, maple, Acer tataricum, damage, DNA barcoding, Asian Russia
Objavljeno v DiRROS: 16.06.2026; Ogledov: 218; Prenosov: 219
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Povzetek: Given the growing interest in nanosized spinel-type ferrite nanoparticles for biomedical applications and the limited information on their safety, this study aimed to assess their cellular and genotoxic effects in an in vitro 3D human hepatic cell model (HepG2 spheroids). Ferrite nanoparticles – γFe2O3 (FeNPs; 14 ± 4 nm), Zn0.7Fe2.3O4 (ZnNPs; 14 ± 5 nm), and Mn0.4Fe2.6O4 (MnNPs; 7 ± 2 nm) – were synthesised through a microwave-assisted polyol route, functionalized with citric acid, and characterised using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). Nanoparticle uptake was analysed using TEM, cytotoxicity was measured with CellTiter-Glo®, and oxidative stress induction was assessed using the 2′,7′-Dichlorodihydrofluorescein diacetate (DCFH-DA) and malondialdehyde (MDA) assay. Genotoxic effects were evaluated using the comet, γH2AX and p-H3 assays. Cellular stress responses were assessed using toxicogenomic analysis. Significant cytotoxicity of the tested nanoparticles (0.1–250 µg/mL) was observed; however, TEM analysis revealed limited penetration to the outermost cell layers of spheroids. Notably, only FeNPs induced ROS generation, while MDA levels remained unchanged in all tested samples. Low DNA damage was detected at 24 h, but a significant increase was observed at 96 h (5–50 µg/mL). No increase in γH2AX or p-H3 was found. No substantial alterations in DNA damage or oxidative stress-response gene expression were detected. Altogether, our findings suggest that the effects of ferrite nanoparticles are time- and composition-dependent, underlining the importance of further mechanistic and chronic exposure evaluations in 3D cell models.
Ključne besede: DNA damage, genotoxicity, HepG2 spheroids, magnetic ferrite-based nanoparticles, ROS induction, safety assessment, toxicogenomics
Objavljeno v DiRROS: 27.01.2026; Ogledov: 609; Prenosov: 793
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Povzetek: Based on the intensive monitoring conducted by our team and volunteers in 2021, the secondary range of an alien horse-chestnut leaf miner, Cameraria ohridella Deschka & Dimić, 1986 (Lepidoptera: Gracillariidae), was specified in European Russia. This invasive pest was confirmed in 24 out of 58 administrative regions of Russia, which it has occupied for approximately 16 years. Analysis of the COI mtDNA gene sequenced in 201 specimens collected in 21 regions of the European part of Russia indicates the occurrence of two haplotypes (A and B), which are also present in the secondary range of C. ohridella in Eastern and Western Europe. The haplotype A dominated and was present in 87.5% of specimens from European Russia. In 2021, C. ohridella produced spectacular outbreaks in Aesculus hippocastanum in southern Russia, where it damaged more than 50% of the leaves in trees in 24 out of 30 distant localities. In the south of the country, the pest infested Acer pseudoplatanus, whereas other species of Acer of European, East Asian, and North American origin showed no signs of attacks. Taking into account that Ae. hippocastanum is present in most regions of European Russia, we expect a further range expansion of C. ohridella up to the Ural Mountains.
Ključne besede: leaf-mining moth, invasion, European Russia, citizen science, DNA barcoding, phylogeography, Aesculus, Acer, damage level
Objavljeno v DiRROS: 17.01.2025; Ogledov: 1156; Prenosov: 830
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Povzetek: The comet assay is used to measure DNA damage induced by chemical and physical agents. High concentrations of test agents may cause cytotoxicity or cell death, which may give rise to false positive results in the comet assay. Systematic studies on genotoxins and cytotoxins (i.e. non-genotoxic poisons) have attempted to establish a threshold of cytotoxicity or cell death by which DNA damage results measured by the comet assay could be regarded as a false positive result. Thresholds of cytotoxicity/cell death range from 20% to 50% in various publications. Curiously, a survey of the latest literature on comet assay results from cell culture studies suggests that one-third of publications did not assess cytotoxicity or cell death. We recommend that it should be mandatory to include results from at least one type of assay on cytotoxicity, cell death or cell proliferation in publications on comet assay results. A combination of cytotoxicity (or cell death) and proliferation (or colony forming efficiency assay) is preferable in actively proliferating cells because it covers more mechanisms of action. Applying a general threshold of cytotoxicity/cell death to all types of agents may not be applicable; however, 25% compared to the concurrent negative control seems to be a good starting value to avoid false positive comet assay results. Further research is needed to establish a threshold value to distinguish between true and potentially false positive genotoxic effects detected by the comet assay.
Ključne besede: comet assay, cytotoxicity, genotoxicity, DNA damage, cell death
Objavljeno v DiRROS: 17.07.2024; Ogledov: 1907; Prenosov: 974
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