Anastasiia Mikhel

Scopus Publications

Evaluation of Oxidative Stress Parameters and Activation of Intracellular Signaling Pathways in the Placenta in Experimental Methionine‑Induced Hyperhomocysteinemia
Yuliya P. Milyutina, Irina V. Zalozniaia, Anastasiia V. Mikhel, Alexandra V. Gorbova, Andrey V. Korenevsky, Gulrukhsor Kh. Tolibova, Alexander V. Arutjunyan, Olesya N. Bespalova
Journal of Obstetrics and Women S Diseases, 2026
BACKGROUND: Maternal hyperhomocysteinemia is commonly regarded as a marker of folate deficiency. However, there is ample evidence to designate this condition as an additional risk factor for obstetric complications, which requires a separate approach to conducting clinical and preclinical studies, and accordingly, to selecting an experimental model for in vivo research. The mechanisms underlying the negative impact of homocysteine and its metabolites on the placenta remain poorly understood. Of interest is the investigation of signaling pathways linking hyperhomocysteinemia to the development of oxidative stress and altered angiogenesis, which leads to insufficient blood flow and placental dysfunction.AIM: The aim of this study was to evaluate oxidative stress and activation of intracellular signaling pathways in the placenta in experimental methionine-induced hyperhomocysteinemia.METHODS: A randomized clinical trial was conducted. Hyperhomocysteinemia in female Wistar rats was induced by daily oral administration of methionine (0.6 g/kg body weight) from day 4 of pregnancy until the material was collected. On days 14 and 20 of pregnancy, the placenta was assessed for oxidative stress parameters, the levels of nuclear factor erythroid 2-related factor 2 (NRF2), tumor protein p53, signal transducer and activator of transcription 3 (STAT3), the activation of p38 mitogen-activated protein kinase (p38 MAPK), and apoptosis-inducing factor (AIF) expression levels.RESULTS: In methionine-induced hyperhomocysteinemia in pregnant rats, the placenta showed an increase in malondialdehyde levels on days 14 and 20 of pregnancy, without changes in catalase activity and antiradical activity. On day 14 of pregnancy, hyperhomocysteinemia in the rat placenta revealed no changes in NRF2, STAT3 and p53 leveles, or the phospho-p38/p38 MAPK ratio. However, on day 20, a decrease in NRF2 levels and an increase in p53 and AIF levels, and the phospho-p38/p38 MAPK ratio were observed.CONCLUSION: The data obtained suggest that increased oxidative stress associated with hyperhomocysteinemia activates signaling pathways in the placenta, including those related to cell death regulation. This may cause disruptions in angiogenesis, leading to adverse pregnancy outcomes.
Prenatal Hyperhomocysteinemia Leads to Synaptic Dysfunction and Structural Alterations in the CA1 Hippocampus of Rats
Tatyana Y. Postnikova, Alexandra V. Griflyuk, Natalia L. Tumanova, Nadezhda M. Dubrovskaya, Anastasia V. Mikhel, Dmitriy S. Vasilev, Aleksey V. Zaitsev
Biomolecules, 2025
Prenatal hyperhomocysteinemia (HCY) is associated with neurodevelopmental deficits, yet its long-term impact on hippocampal synaptic function remains poorly understood. This study examines the effects of moderate maternal HCY on excitatory synaptic transmission in the CA1 region of the dorsal hippocampus in rat offspring at juvenile (P21) and adult (P90) stages. Using field postsynaptic potential (fPSP) recordings, electron microscopy, and Western blot analysis, we observed a significant age-dependent decline in the efficiency of excitatory synaptic transmission in HCY-exposed rats. Electron microscopy revealed structural alterations, including synaptic vesicle agglutination in the stratum radiatum, suggesting impaired neurotransmitter release. Additionally, a significant reduction in pyramidal neuron density was observed in the CA1 region, although seizure susceptibility remained unchanged. Western blot analysis showed altered expression of Synapsin I, indicating presynaptic dysfunction. These findings suggest that moderate prenatal HCY leads to persistent deficits in synaptic transmission and structural integrity, potentially contributing to cognitive impairments in adulthood. Our results highlight the importance of maternal homocysteine levels in shaping hippocampal function and could offer insights into neurodevelopmental disorders associated with metabolic disturbances.
Oxidative stress parameters in seminal plasma of men with high sperm DNA fragmentation
A.V. Mikhel, Yu.P. Milyutina, Ya.M. Sagurova, M.A. Ishchuk, E.M. Komarova, A.M. Gzgzyan, A.V. Korenevsky, N.I. Tapilskaya
Russian Journal of Human Reproduction, 2025
ABSRACT Introduction. In recent years, increasing attention has been paid to the issue of male reproductive health. The WHO guidelines state that the primary assessment of male fertility is reduced to a “basic semen examination” (concentration, morphology assessment, etc. of sperm). The study of DNA fragmentation, on the other hand, falls under the “expanded” list of tests. At the same time, a thorough evaluation of the antioxidant system’s activity and, in particular, the amount of oxidative modification products of macromolecules, is not included in this list. Sperm are sensitive cells to the effects of reactive oxygen species. Current research focuses on their condition and microenvironment, aimed at detecting the relationship between sperm quality and the development of oxidative stress. However, the question of whether to conduct an expanded and in-depth analysis in cases of normal sperm motility remains unresolved. Objective. The aim of this study was to evaluate the parameters of the antioxidant system and products of oxidative modifications of proteins and DNA of seminal plasma and spermatozoa at a normal level of their mobility and varying DNA fragmentation. Material and methods. This selective pilot single-center cross-sectional study included healthy men with different DNA fragmentation and normal sperm motility. We assessed the oxidative modifications of macromolecules (8-hydroxy-2’-deoxyguanosine; nitrotyrosine) and components of the antioxidant system (total antioxidant activity, catalase activity, superoxide dismutase activity, uric acid, and zinc ions) in seminal plasma and the cellular fraction of the ejaculate. Differences were considered significant at p<0.050. Results. Using the exclusion criteria, we selected 37 patients. In the seminal plasma of men with TUNEL>15, a decrease in superoxide dismutase activity (p<0.010), zinc ion levels (p<0.050) and uric acid content (p<0.050) was observed, while an increase in nitrotyrosine content (p<0.050) was observed only in the cellular fraction of the ejaculate. Conclusions. The obtained data indicate that in men, despite normal sperm motility, a high degree of DNA fragmentation is associated with abnormal head morphology, highlighting the necessity of conducting an “expanded” semen examination. Changes in the components of the antioxidant system are found not within the cells themselves but in their microenvironment, which may likely lead to an increased formation of oxidative modification products of macromolecules in sperm. This is important to consider when collecting samples for ART protocols, as well as in relation to the overall quality and reproductive potential of sperm, which is crucial when planning for pregnancy.
Autophagy marker dynamics in the fetal brain and placenta of rats in hyperhomocysteinemia
Anastasiia V. Mikhel, Irina V. Zalozniaia, Anastasiia D. Shcherbitskaia, Dmitrii S. Vasilev, Yuliya P. Milyutina, Gleb O. Kerkeshko, Alexandra V. Gorbova, Natalia L. Tumanova, Alexander V. Arutjunyan
Journal of Obstetrics and Women S Diseases, 2025
BACKGROUND: Autophagy is essential for placenta formation and fetal brain development. Maternal hyperhomocysteinemia is a risk factor for pregnancy complications and may affect autophagy processes. However, the dynamics of autophagy markers are not studied enough so far.AIM: The aim of this study was to assess the dynamics of key autophagy markers in the fetal brain and various parts of the placenta of rats throughout pregnancy under normal conditions and in the presence of maternal hyperhomocysteinemia.MATERIALS AND METHODS: Pregnant Wistar rats were induced with hyperhomocysteinemia by chronic administration of L-methionine. Placental and fetal brain tissues were collected on days 14 and 20 of gestation. Levels of autophagy markers (Beclin-1; phosphatidylethanolamine conjugated form microtubule-associated protein 1A/1B light chain 3B (LC3B-II); lysosomal associated membrane protein 2 (LAMP-2)] were determined by Western blotting. Ultrastructural changes were examined using electron microscopy.RESULTS: In the control group, by the end of pregnancy (gestational day 20) compared to gestational day 14, we observed an increase in LAMP-2 level in the maternal part of the placenta and a decrease in LC3B-II level in the fetal part of the placenta. In maternal hyperhomocysteinemia in the maternal part of the placenta, we found an increase in LAMP-2 level on gestational day 14 and in LC3B-II level from gestational day 14 to gestational day 20. In the fetal part of the placenta, under the same conditions, we observed a decrease in LC3B-II level on gestational day 14 and an increase in LAMP-2 level by the end of pregnancy. In the fetal brain, a decrease in Beclin-1 level from gestational day 14 to gestational day 20 was shown in the both study groups, while under the influence of hyperhomocysteinemia, the levels of the autophagy markers remained unchanged. Under L-methionine load, pathological ultrastructural changes were observed in the fetal part of the placenta and fetal brain at the both time points studied. Normally and under the influence of hyperhomocysteinemia, autophagosomes were found in placental cells on gestational days 14 and 20, while in brain cells, they were only present on gestational day 20.CONCLUSIONS: The data obtained suggest that autophagy activity in the placenta and fetal brain in normal conditions and under maternal hyperhomocysteinemia depends on the gestational age. Changes in the dynamics of autophagy may be a reason for impaired placental formation and dysfunction in hyperhomocysteinemia. The absence of significant changes in autophagy markers in the fetal brain under hyperhomocysteinemia conditions may result from protective mechanisms in the placenta or/and the resilience of autophagy processes in nervous tissue.
Placental Transport of Amino Acids in Rats with Methionine-Induced Hyperhomocysteinemia
Yulia P. Milyutina, Gleb O. Kerkeshko, Dmitrii S. Vasilev, Irina V. Zalozniaia, Sergey K. Bochkovskii, Natalia L. Tumanova, Anastasiia D. Shcherbitskaia, Anastasiia V. Mikhel, Gulrukhsor H. Tolibova, Alexander V. Arutjunyan
Biochemistry Moscow, 2024
Maternal hyperhomocysteinemia (HHcy) is a risk factor for intrauterine growth restriction presumably caused by a decrease in the placental transport of nutrients. We investigated the effect of experimental HHcy induced by daily methionine administration to pregnant rats on the free amino acid levels in the maternal and fetal blood, as well as on morphological and biochemical parameters associated with the amino acid transport through the placenta. HHcy caused an increase in the levels of most free amino acids in the maternal blood on gestational day 20, while the levels of some amino acids in the fetal blood were decreased. In rats with HHcy, the maternal sinusoids in the placental labyrinth were narrowed, which was accompanied by aggregation of red blood cells. We also observed an increase in the neutral amino acid transporters (LAT1, SNAT2) protein levels and activation of 4E-BP1, a downstream effector of mTORC1 complex, in the labyrinth zone. Maternal HHcy affected the placental barrier permeability, as evidenced by intensification of the mother-to-fetus transfer of Evans Blue dye. The imbalance in the free amino acid levels in the maternal and fetal blood in HHcy may be due to the competition of homocysteine with other amino acids for common transporters, as well as a decrease in the area of exchange zone between maternal and fetal circulations in the placental labyrinth. Upregulation of the neutral amino acid transporter expression in the labyrinth zone may be a compensatory response to an insufficient intrauterine amino acid supply and fetal growth restriction.
Reference Gene Validation in the Embryonic and Postnatal Brain in the Rat Hyperhomocysteinemia Model
Anna A. Kovalenko, Alexander P. Schwarz, Anastasiia D. Shcherbitskaia, Anastasiia V. Mikhel, Dmitrii S. Vasilev, Alexander V. Arutjunyan
Neurotoxicity Research, 2024
Age-Related COVID-19 Influence on Male Fertility
Anastasiia D. Shcherbitskaia, Evgeniia M. Komarova, Yulia P. Milyutina, Yanina M. Sagurova, Mariia A. Ishchuk, Anastasiia V. Mikhel, Ksenia V. Ob’edkova, Elena A. Lesik, Alexander M. Gzgzyan, Natalya I. Tapilskaya, Olesya N. Bespalova, Igor Y. Kogan
International Journal of Molecular Sciences, 2023
The impact of coronavirus on the reproductive health of men attracts the special attention of many researchers. While studies suggest changes in sperm parameters and the possibility of testicular inflammation, further studies are needed to elucidate any potential age-related changes in these findings, which is the purpose of the present study. The semen quality parameters, cytokine concentration, and markers of the pro- and antioxidant system were assessed in 60 men five to seven months after the coronavirus infection and in 77 controls (without a history of coronavirus infection). Additionally, participants were divided into two age groups: less than 35 years and 35 years or older. Notably increased round cell count in ejaculate and reduced sperm hyaluronan binding ability were observed among post-infection patients younger than 35 years. In the same group, a decline in seminal plasma zinc levels and nitrotyrosine in the cell fraction was found. In men over 35 years of age, Coronavirus Disease 2019 (COVID-19) led to increased sperm DNA fragmentation, a decrease in the total antioxidant capacity, and an elevation in the levels of interleukin-1β and interleukin-10. The concentration of interleukin-1β decreased over time following recovery in all affected patients. The data obtained suggest the potential adverse impact of the coronavirus infection on male reproductive health; however, these effects appear to be age-dependent.
Imbalance of Angiogenic and Growth Factors in Placenta in Maternal Hyperhomocysteinemia
Alexander V. Arutjunyan, Gleb O. Kerkeshko, Yulia P. Milyutina, Anastasiia D. Shcherbitskaia, Irina V. Zalozniaia, Anastasiia V. Mikhel, Daria B. Inozemtseva, Dmitrii S. Vasilev, Anna A. Kovalenko, Igor Yu. Kogan
Biochemistry Moscow, 2023
Abstract Numerous studies have shown that various adverse factors of different nature and action mechanisms have similar negative influence on placental angiogenesis, resulting in insufficiency of placental blood supply. One of the risk factors for pregnancy complications with placental etiology is an increased level of homocysteine in the blood of pregnant women. However, the effect of hyperhomocysteinemia (HHcy) on the development of the placenta and, in particular, on the formation of its vascular network is at present poorly understood. The aim of this work was to study the effect of maternal HHcy on the expression of angiogenic and growth factors (VEGF-A, MMP-2, VEGF-B, BDNF, NGF), as well as their receptors (VEGFR-2, TrkB, p75NTR), in the rat placenta. The effects of HHcy were studied in the morphologically and functionally different maternal and fetal parts of the placenta on the 14th and 20th day of pregnancy. The maternal HHcy caused increase in the levels of oxidative stress and apoptosis markers accompanied by an imbalance of the studied angiogenic and growth factors in the maternal and/or fetal part of the placenta. The influence of maternal HHcy in most cases manifested in a decrease in the protein content (VEGF-A), enzymatic activity (MMP-2), gene expression (VEGFB, NGF, TRKB), and accumulation of precursor form (proBDNF) of the investigated factors. In some cases, the effects of HHcy differed depending on the placental part and stage of development. The influence of maternal HHcy on signaling pathways and processes controlled by the studied angiogenic and growth factors could lead to incomplete development of the placental vasculature and decrease in the placental transport, resulting in fetal growth restriction and impaired fetal brain development.
Maternal Hyperhomocysteinemia Disturbs the Mechanisms of Embryonic Brain Development and Its Maturation in Early Postnatal Ontogenesis
Dmitrii S. Vasilev, Anastasiia D. Shcherbitskaia, Natalia L. Tumanova, Anastasiia V. Mikhel, Yulia P. Milyutina, Anna A. Kovalenko, Nadezhda M. Dubrovskaya, Daria B. Inozemtseva, Irina V. Zalozniaia, Alexander V. Arutjunyan
Cells, 2023
Maternal hyperhomocysteinemia causes the disruption of placental blood flow and can lead to serious disturbances in the formation of the offspring’s brain. In the present study, the effects of prenatal hyperhomocysteinemia (PHHC) on the neuronal migration, neural tissue maturation, and the expression of signaling molecules in the rat fetal brain were described. Maternal hyperhomocysteinemia was induced in female rats by per os administration of 0.15% aqueous methionine solution in the period of days 4–21 of pregnancy. Behavioral tests revealed a delay in PHHC male pups maturing. Ultrastructure of both cortical and hippocampus tissue demonstrated the features of the developmental delay. PHHC was shown to disturb both generation and radial migration of neuroblasts into the cortical plate. Elevated Bdnf expression, together with changes in proBDNF/mBDNF balance, might affect neuronal cell viability, positioning, and maturation in PHHC pups. Reduced Kdr gene expression and the content of SEMA3E might lead to impaired brain development. In the brain tissue of E20 PHHC fetuses, the content of the procaspase-8 was decreased, and the activity level of the caspase-3 was increased; this may indicate the development of apoptosis. PHHC disturbs the mechanisms of early brain development leading to a delay in brain tissue maturation and formation of the motor reaction of pups.
Prenatal hyperhomocysteinemia induces glial activation and alters neuroinflammatory marker expression in infant rat hippocampus
Anastasiia D. Shcherbitskaia, Dmitrii S. Vasilev, Yulia P. Milyutina, Natalia L. Tumanova, Anastasiia V. Mikhel, Irina V. Zalozniaia, Alexander V. Arutjunyan
Cells, 2021
Maternal hyperhomocysteinemia is one of the common complications of pregnancy that causes offspring cognitive deficits during postnatal development. In this study, we investigated the effect of prenatal hyperhomocysteinemia (PHHC) on inflammatory, glial activation, and neuronal cell death markers in the hippocampus of infant rats. Female Wistar rats received L-methionine (0.6 g/kg b.w.) by oral administration during pregnancy. On postnatal days 5 and 20, the offspring’s hippocampus was removed to perform histological and biochemical studies. After PHHC, the offspring exhibited increased brain interleukin-1β and interleukin-6 levels and glial activation, as well as reduced anti-inflammatory interleukin-10 level in the hippocampus. Additionally, the activity of acetylcholinesterase was increased in the hippocampus of the pups. Exposure to PHHC also resulted in the reduced number of neurons and disrupted neuronal ultrastructure. At the same time, no changes in the content and activity of caspase-3 were found in the hippocampus of the pups. In conclusion, our findings support the hypothesis that neuroinflammation and glial activation could be involved in altering the hippocampus cellular composition following PHHC, and these alterations could be associated with cognitive disorders later in life.
Neurotrophins of the Fetal Brain and Placenta in Prenatal Hyperhomocysteinemia
A. V. Arutjunyan, Yu. P. Milyutina, A. D. Shcherbitskaia, G. O. Kerkeshko, I. V. Zalozniaia, A. V. Mikhel
Biochemistry Moscow, 2020

Anastasiia Mikhel

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Scopus Publications