Hybridogenesis in an interspecific hybrid frog is a coupling mechanism in the gametogenic cell line that eliminates the genome of one parental species with endoduplication of the remaining genome of the other parental species. It has been intensively investigated in the edible frog Pelophylax kl. esculentus (RL), a natural hybrid between the marsh frog P. ridibundus (RR) and the pool frog P. lessonae (LL). However, the genetic mechanisms involved remain unclear. Here, we investigated the water frogs in the western Russian territory. In three of the four populations, we genetically identified 16 RL frogs living sympatrically with the parental LL species, or with both parental species. In addition, two populations contained genome introgression with another species, P. bedriagae (BB) (a close relative of RR). In the gonads of 13 RL frogs, the L genome was eliminated, producing gametes of R (or R combined with the B genome). In sharp contrast, one RL male eliminated the L or R genome, producing both R and L sperm. We detected a variation in genome elimination within a population. Based on the genetic backgrounds of RL frogs, we hypothesize that the introgression of the B genome resulted in the change in choosing a genome to be eliminated.

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Authors analyzed the relationship of the most studied polymorphisms of glutathione-S-transferase genes (GSTT1, GSTM1, GSTP1) with the risk of developing diseases in the territory of the Russian Federation. The authors analyzed domestic articles on gene polymorphisms and their association with various conditions. A systematic review of scientific papers was carried out using the following electronic databases: Cyberleninka, Electronic Library and Google Scholar, which searched for glutathione transferase (GST) gene polymorphisms from 1900 to 2020. The following keywords were used for the search: “GST polymorphism”. The search for articles was carried out in English but took into account the results obtained only in the territory of the Russian Federation. The search for scientific publications was independently checked and compared to filter out duplicate articles. The sample size, the number of loci included in the analysis, and the analyzed population (ethnic group) are essential in studying the relationship between glutathione S-transferase gene polymorphisms and the development of diseases. In general, the analysis of the articles makes it possible to reveal the association between the polymorphisms of the glutathione-S-transferase genes and the high risk of developing oncological diseases, respiratory diseases and other pathologies. This article did not consider the relationship of polymorphisms with reproductive pathologies because this topic includes a large amount of work and requires separate consideration. The least studied issue is the relationship between polymorphisms of genes for biotransformation of xenobiotics and the development of occupational diseases.

Introduction. Industrial pollution of the workplace air and the environment with lead oxide nanoparticles (PbO NPs) poses the risk of neurodegenerative diseases in workers of lead and copper smelters and the population living around these enterprises. Various studies showed the involvement of N-methyl-D-aspartate (NMDA) receptor expression in the mechanisms of lead toxicity. Materials and methods. During two months, outbred female rats were exposed to lead nanoparticles (PbO NPs) at a concentration of 0.2 mg/m3 in a “nose-only” inhalation exposure system. The behavioral responses of the rats were assessed using the open field and the elevated plus maze tests. Quantitative expression of the NMDA receptor genes (GRIN1, GRIN2A, GRIN2B) in the rat hippocampus was assessed using a real-time PCR. Statistical data analysis was carried out using the Mann-Whitney U test. Results. The neurotoxic effect of PbO NPs manifested itself in the suppression of GRIN2A gene expression in the hippocampus of experimental rats. The expression of the GRIN1 gene also showed a tendency to decrease in rats under effect of PbO NPs, while the expression of the GRIN2B gene did not change. The results of the open field test did not reveal any differences between the experimental and control groups of rats. The elevated plus maze test revealed a significant decrease in the number of entries into the open arms of the maze in rats from the experimental group. Limitations. This work was performed on female Wistar rats and does not take into account possible inter-gender differences. Conclusion. The results of the experiment demonstrated the neurotoxic effect of PbO NPs including the reduced expression level of the GRIN2A gene of the NMDA receptor and a decrease in the proportion of time spent in the open arms in the elevated plus maze test.

Introduction. Copper plays an important role in the metabolism of the brain, but particles of copper, in the nanometer range, exhibit neurotoxic properties and cause malfunctioning of brain cells. Material and methods. For 6 weeks, 3 times a week, the animals were injected with a suspension of NPs of copper oxide. The determination of the expression of the genes GRIN1, GRIN2a, and GRIN2b, encoding the proteins GluN1, GluN2a, and GluN2b, respectively, was carried out by real-time PCR with probes. Results. A statistically significant decrease in the expression level of genes encoding NMDA receptor proteins was determined when exposed to 0.5 mg/ml CuO nanoparticles (ΔCt(GRIN1) = 0.813; ΔCt(GRIN2A) = 3.477; ΔCt(GRIN2B) = 1.37) in comparison with control group (ΔCt(GRIN1) = 6.301; ΔCt(GRIN2A) = 7.823; ΔCt(GRIN2B) = 4.747). Conclusion. Evaluation of gene expression of the NMDA receptor may be present in a genetic marker to determine the toxic effect of copper oxide nanoparticles; however, further studies are needed, including behavioral tests to confirm the clinical manifestations of neurodegenerative disorders.

Introduction. Cardiovascular diseases are the leading cause of death in the population, their diagnosis and prevention are of great importance nowadays. Ferrous metallurgy workers are exposed to occupational risk factors, which, together with a genetic predisposition, can induce and affect progression of diseases of the circulatory system. The Ala16Val (rs4880) polymorphism influences the functioning of the superoxide dismutase enzyme, which catalyzes the first step in the removal of reactive oxygen species, and can be therefore associated with cardiovascular diseases and comorbidities. Our objective was to study the relationship between SOD2 gene Ala16Val polymorphism and blood pressure, body mass index, and biochemical blood test parameters (total cholesterol and glucose levels) in iron and steel production employees. Materials and methods. The study cohort included ninety eight 24 to 66 years (mean: 48.8 ± 8.3 years) male patients working in the converter shop of a metallurgical plant. Genomic DNA was isolated using the LumiPure kit (Lumiprobe, Russia) in accordance with the manufacturer’s instructions for use. Genotyping was performed using a QuantStudioTM 3 real-time PCR system (ThermoFisher, USA) and a commercial SNP-Screen kit (Synthol, Russia). Results. The Val/Val genotype was associated with higher systolic and diastolic blood pressure, and total blood cholesterol. Limitations. The study limitations include the lack of comprehensive data on working conditions in the sanitary and hygienic characteristics presented. There is no control group in the study, which does not allow assessing the contribution of occupational risk factors to the development of cardiovascular diseases in carriers of the Val/Val genotype. However, our sample can be considered representative, which allows applying the findings to assessing health risks for the adult working-age population involved in ferrous metals production with account for regional features. Conclusion. We assume that the Val/Val genotype is associated with risk factors for cardiovascular disease in the metallurgists due to the reduced antioxidant potential.

Copper is an essential trace element for human health and, at the same time, a major industrial metal widely used both in its elemental form and in compounds. We conducted a dose-dependent assessment of the response of outbred albino male rats to subchronic low-dose exposure to copper oxide nanoparticles administered intraperitoneally at cumulative doses of 18 and 36 mg/kg during 6 weeks to exposure groups 1 and 2, respectively. We observed disorders at different levels of organization of the body in the exposed animals, from molecular to organismal. The observed decrease in the activity of succinate dehydrogenase in nucleated blood cells gave evidence of impaired bioenergetics processes. In view of the results of the metabolomics analysis, we assume mitochondrial damage and contribution of apoptotic processes to the pathology induced by copper poisoning. We also assume neurodegenerative effects based on the assessed morphological parameters of the nervous system, results of behavioral tests, and a decreased level of expression of genes encoding NMDA receptor subunits in the hippocampus. The hepatotoxic effect noted by a number of metabolomics-based, biochemical, and cytological indicators was manifested by the impaired protein-synthesizing function of the liver and enhanced degenerative processes in its cells. We also observed a nephrotoxic effect of nanosized copper oxide with a predominant lesion of proximal kidney tubules. At the same time, both doses tested demonstrated such positive health effects as a statistically significant decrease in the activity of alkaline phosphatase and the nucleated blood cell DNA fragmentation factor. Judging by the changes observed, the cumulative dose of copper oxide nanoparticles of 18 mg/kg body weight administered intraperitoneally approximates the threshold one for rats. The established markers of health impairments may serve as a starting point in the development of techniques of early diagnosis of copper poisoning.

Introduction. This review is devoted to the association of GSTM1, GSTT1, GSTP1 gene polymorphisms with various diseases in foreign literature sources. Material and methods. For this article, we used data published in foreign literature over the past 11 years. medline was extensively searched for eligible studies using the Pubmed search engine, and 30 studies were eventually selected for inclusion in this review. Results. This review showed that researchers all over the world have repeatedly tried to evaluate the relationship between GST polymorphisms and various diseases, but in some cases received conflicting results. At the same time, many studies have found an association of pathologies with both single GST gene polymorphisms and combined polymorphic variants, which indicates a complex effect of antioxidant system genes. Limitation of the study. The limitation of this review is the lack of domestic literary sources. Conclusion. Further research of functional polymorphisms of the GST family genes are needed to develop effective systems for the diagnosis, prevention, and treatment of diseases.