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卷 70, 编号 4 (2025)
Molecular biophysics
The Nature of Thiol-Containing Ligands in Dinitrosyl Iron Complexes as a Factor Determining the Stability of These Complexes
摘要
The stability of the binuclear form of dinitrosyl iron complexes with various thiol-containing ligands, such as glutathione, L-cysteine, N-acetyl-L-cysteine, mercaptoethanol, and mercaptosuccinate, has been compared based on the results of exposure of these complexes in an aqueous medium at pH 1.0–2.0, leading to their decomposition as a result of protonation of the thiol group of thiol-containing ligands with the release of nitric oxide from the complexes (NO) and nitrosonium (NO+) cations. Complexes with L-cysteine and mercaptosuccinate turned out to be the least stable: they decomposed in acidic solutions at room temperature, whereas the more stable complexes with N-acetyl-L-cysteine, mercaptoethanol, or glutathione decomposed when their solutions were heated at 70–80°C. The decomposition of all these complexes under these conditions occurred within a few minutes with a concentration ratio of “free” (not included in the complexes) thiols and the complexes themselves not exceeding 1 : 2. With an increase in this ratio, the decay time of the complexes increased symbatically with the level of free thiols. The mononuclear form of the thiosulfate complexes decomposed at a thiosulfate-to-complex concentration ratio of 2 for several minutes in an aqueous solution at neutral pH values.
Biophysics. 2025;70(4):629–645
629–645
Effect of Thr-Ser-Lys-Tyr Peptide on Actin Polymerization in vitro
摘要
The effect of the peptide Thr-Ser-Lys-Tyr isolated from the brain of the obligate hibernating long-tailed ground squirrel Urocitellus undulatus (formerly Citellus undulatus, Spermophilus undulatus) on the polymerization/depolymerization of actin in vitro was studied by electron microscopy. Upon incubation of the peptide with globular (monomeric) actin at concentrations of 0.1 mg/ml (in a ratio of 1 : 1), the formation of single filaments of actin was observed. When the peptide was added to the formed actin filaments, no effects were observed, in particular, actin depolymerization. The possible involvement of the peptide in the polymerization of actin in vivo and a possible contribution to the restoration of the functional activity of the central nervous system after the hibernating animal leaves the state of hypothermia are discussed.
Biophysics. 2025;70(4):646–651
646–651
Cell biophysics
Oxygenic Photosynthesis in silico: Ferredoxin and Alternative Electronic Transport Pathways
摘要
The paper is devoted to the mathematical analysis of alternative electron transport routes in chloroplasts related to the functioning of ferredoxin molecules located at the “fork” of electron transport pathways on the acceptor side of photosystem I. This study is based on the kinetic model proposed by us earlier, which describes the phototransformation of the reaction centers of photosystem I and photosystem II, ferredoxin, plastoquinone, and plastocyanin molecules, as well as the processes of trans-thylakoid proton transfer and ATP synthesis. The effect of alternative channels of electron outflow from ferredoxin molecules (reduction of molecular oxygen, cyclic electron transport around photosystem I, reduction of thioredoxin) on the dynamics of light-induced redox transformations of electron transport chain carriers has been studied. It has been shown that increased electron outflow from photosystem I contributes to an increase in the efficiency of photosystem I centers, which is especially important at the initial stages of chloroplast illumination when the Calvin-Benson cycle is inactive. Alternative electron fluxes make it possible to maintain a sufficiently high trans-thylakoid pH difference (ΔpH ≈ 1.8), ensuring efficient synthesis of ATP molecules.
Biophysics. 2025;70(4):652–663
652–663
Investigation of the Interaction of Charged Nanoparticles with the Cell Membrane of Erythrocytes
摘要
Aerosols made of highly charged nanoparticles of non-volatile substances are of interest for the development of new highly effective methods of targeted drug delivery. However, for safe use, it is necessary to study their possible damaging effect on cell membranes. Human erythrocytes were selected as a model system. The experiments were carried out under conditions of partial dehydration of cells with exposure of a part of the surface of red blood cells to air to ensure contact of the sprayed particles with the cell membrane. It was found that, while highly charged nanoaerosolic particles during direct electron spraying are capable of disrupting the structure of the lipid monolayer, they do not cause damage to the cell membrane of erythrocytes. Thus, the results of the work can be used in the development of an electro-spraying method for the delivery of medicinal drugs to wound surfaces, the olfactory bulb, etc. The developed devices can also be used in studies of the interaction of nanoaerosols of various substances with the cell membrane.
Biophysics. 2025;70(4):664–669
664–669
Optimization of the Method for Measuring 2,3-Diphosphoglycerate in Erythrocytes Using 31P NMR Analysis
摘要
It has been shown by 31P NMR spectroscopy that reducing the number of washes of rat erythrocytes significantly increases the stability of 2,3-diphosphoglycerate in these samples. The level of 2,3-diphosphoglycerate remains unchanged for 3.5 hours with a single wash and for 4 hours without washing. At the same time, with standard double washing, the content of 2,3-diphosphoglycerate decreases already after 2.5 hours. Analysis of its distribution between red blood cells and removed plasma, as well as analysis of the serum of one animal, showed that all 2,3-diphosphoglycerate remains in the suspension of red blood cells and is absent in plasma and serum. The results obtained should be taken into account when working with intact erythrocytes.
Biophysics. 2025;70(4):670–676
670–676
Heterogenous Properties of Potassium Glutamate Neurones in the Ventral and Dorsal Zones of the CA1 Hippocampus
摘要
A comparative study of the electrophysiological characteristics of pyramidal (PC) neurons of the dorsal and ventral parts of the CA1 zone of the hippocampus of mice was conducted using the patch-clamp method in the “whole cell” configuration. The potassium load was used as a parameter for cell type discrimination (an increase in [K+]o from 3.0 to 8.5 mM in the medium). It has been established that two types of cells with different sensitivity to potassium are registered in both parts of the CA1 zone. In PC-A type cells, the burst activity caused by a step of current I (from 10 to 200 pA) is potentiated by potassium with an increase in [K+]o to 8.5 mM, whereas in PC-I type cells at currents I < 100 pA there is no effect of potassium loading, and at currents ≥ 125 pA, suppression of burst activity is observed. The ratio of the number of PC-A/PC-I cells in the ventral and dorsal parts is 16 : 5 and 8 : 8, respectively. Potassium potentiation of burst activity is higher in ventral PC-A cells than in dorsal cells. Only in PC-A cells with potassium loading, the threshold current (Ith) decreases by 2.5 times and a spontaneous burst (pacemaker) activity is manifested. The Sag potential and the adaptation index of induced impulse activity are higher in the ventral PC-A cells than in the dorsal ones. The potassium load reduces the Sag potential. An analysis of the voltage characteristics shows that incoming and outgoing (predominantly) slow potassium currents are activated under potassium load. The currents in the ventral neurons of both types are 1.5–2.0 times lower than in the dorsal ones (at –100 mV and +20 mV). Taken together, these data suggest that K+ o-sensitive ventral PC-A cells can play an important role in hyper-excitation of neural networks and induction of epileptogenesis.
Biophysics. 2025;70(4):677–689
677–689
Betahistine Normalizes the State of Mitochondria in Deiters Neurons during Vestibular Stimulation
摘要
The state of mitochondria in neurons of the lateral vestibular nucleus of Deiters in mice after 8-hour vestibular stimulation was studied. It was shown that an hour after stimulation, significant changes occurred in the mitochondria of Deiters neurons: an increase in area, a disruption in the structure of cristae, and the presence of mitophagosomes. At the same time, the mRNA levels of proteins-markers of mitochondrial biogenesis (PGC-1α), their division (DRP-1), and fusion of the outer and inner mitochondrial membranes (MFN1, MFN2, OPA) increased, indicating activation of mitogenesis in Deiters neurons as a result of stimulation of the vestibular system. The administration of betahistine 30 minutes before stimulation at a dose of 300 mg/kg prevented mitochondrial disorders and the formation of mitophagosomes. The obtained data indicate that under increased vestibular stimulation, Deiters neurons can undergo significant damage. The revealed mechanisms of mitochondrial damage allow us to define a potential strategy for the treatment of diseases associated with impaired mitochondrial dynamics (e.g., neurodegenerative diseases or ischemia).
Biophysics. 2025;70(4):690–698
690–698
The Effect of the Peptide TSKY on the Physiological Activity of the Bovine Spermatozoa
摘要
The development of cryopreservation methods for testicular spermatozoa makes it possible to safely and economically reproduce genetically diverse agricultural and numerous endangered animal species. The effect of the peptide TSKY (Thr-Ser-Lys-Tyr) isolated from the brain of winter-sleeping ground squirrels (Spermophillus undulatus) in a state of deep hibernation on the physiological activity of bovine sperm cells was studied. A decrease in the activity of bovine fast-moving spermatozoa was shown when TSKY peptide was added at the thawing stage after cryopreservation of reproductive cells in liquid nitrogen (–196°C).
Biophysics. 2025;70(4):699–703
699–703
The Effect of Cholesterol on Spermatozoa Membranes: Investigation Using Spin Probes
摘要
Cholesterol plays an important role in the structural organization and functioning of sperm membranes. The purpose of this work was to study the structural changes of human sperm membranes using spin probes after removing cholesterol from them with the help of methyl-β-cyclodextrin, which binds cholesterol. Using a model system (liposomes with different cholesterol content), it was shown that the presence of cholesterol in liposomes affects the EPR spectra of the spin probe of 5-doxyl-stearic acid dissolved in the lipid bilayer, causing an increase in the microviscosity of the membrane. The extraction of cholesterol from sperm membranes by spermatozoa treatment with methyl-β-cyclodextrines caused changes in the EPR spectra of 5-doxyl-stearic acid dissolved in sperm membranes, demonstrating the membrane fluidization.
Biophysics. 2025;70(4):704–714
704–714
Effect of Ethanol on Proliferation, Contraction and Migration of Vascular Smooth Muscle Cells from Rat Aorta
摘要
The aim of the work is to study the effect of 24-hour effect of ethanol (50 and 100 mmol/L) on proliferation, contraction and migration of vascular smooth muscle cells (VSMCs) from rat thoracic aorta. The following age groups of rats were studied: early neonatal period of development (1-week-old rats), puberty age (5-month-old rats) and the initial period of aging (1-year-old rats). The following methods were used in the work: real-time PCR to assess the proliferation of VSMCs by comparing the relative amount of genomic DNA between the control and the experiment; wound healing assay to determine the migration of VSMCs; the collagen gel contraction assay to assess the contraction of VSMCs. Ethanol 50 mmol/L did not have effect on the studied parameters of VSMCs. Ethanol 100 mmol/L resulted in: increase of proliferation ~38% (р ≤0.01) and decrease the contraction ~12% (р ≤ 0.01) of VSMCs of rats of the early neonatal period of development; decrease the contraction ~7% (р ≤ 0.01) and proliferation ~21% (р ≤ 0.01) of VSMCs of rats of puberty age and animals of the initial period of aging, respectively. Thus, ethanol 100 mmol/L had different effects on VSMCs of rats depending on age group of animals. It is worth noting that VSMCs of rats of the early neonatal period of development are more sensitive to effects of ethanol.
Biophysics. 2025;70(4):715–723
715–723
Expression of Cellular Chaperones and Co-Chaperones Associated with Heat Shock Proteins Hsp90 and Hsp70 in Human Fibrosarcoma HT1080 Cells That Do Not Synthesize Hsp90β
摘要
Heat shock protein Hsp90 is an important cellular chaperone, it contributes to the folding, stabilization, and regulation of specific target proteins involved in many cellular processes. Mammalian cells contain two isoforms of Hsp90 – the inducible isoform of Hsp90α and the constitutive isoform of Hsp90β. Recently, we showed that knockout of the HSP90AB1 gene encoding the constitutive isoform of Hsp90β in human fibrosarcoma HT1080 cells (Hsp90β-KO cells) did not affect cell proliferation and resistance to heat shock and oxidative stress, and slightly reduced cell migration. This indicates the adaptation of cells and the cellular chaperone machinery to the loss of one of the key cellular chaperones, Hsp90β. In this work, using real-time quantitative PCR and Western blotting, we found that knockout of the gene encoding Hsp90β was accompanied by changes in the expression and content of individual chaperones and co-chaperones associated with Hsp90 and Hsp70 chaperone machinery. In the HSP90 family of chaperones/co-chaperones, an increase in the expression and content of the cytosolic isoform of Hsp90α remaining in the cell and up-regulation of a number of important Hsp90 co-chaperones (FKBP4, HOP) were observed. In the HSP70 family of chaperones/co-chaperones, the expression and content of key chaperones, inducible Hsp70, constitutive Hsc70 and mitochondrial GRP75, were significantly increased. As a result, some mechanisms of adaptation of Hsp90 and Hsp70 chaperone machineries in response to the loss of one of the key chaperones, Hsp90β, by cells have been established for the first time. The Hsp90b-KO cells we created that do not express Hsp90β can be considered as a cellular model of pharmacological inhibition of Hsp90β function by promising Hsp90β-specific inhibitors created for tumor therapy. The revealed changes in Hsp90- and Hsp70-associated chaperones and co-chaperones in response to the loss of Hsp90β demonstrate probable changes in the cellular chaperone machine caused by the suppression of Hsp90β by such inhibitors and can be taken into account when developing combined therapeutic strategies using Hsp90β-specific inhibitors.
Biophysics. 2025;70(4):724–735
724–735
Mechanisms of Drug Resistance of Acute Myeloid Leukemia Cells in Three-Dimensional High-Density Cultures: A Study of Intracellular Accumulation of Chemotherapeutic Drugs
摘要
Intracellular accumulation of chemotherapeutic drugs in resistant cells of acute myeloid leukemia cultured in a three-dimensional high-density culture was studied. It was shown that neither the dense arrangement of cells, nor the main ABC family transporter proteins most likely affect the increase in drug resistance of acute myeloid leukemia cells in a three-dimensional high-density cell culture. These data indicate the involvement of other mechanisms in increasing drug resistance in three-dimensional high-density cell cultures of acute myeloid leukemia.
Biophysics. 2025;70(4):736–741
736–741
The Role of Generation of Reactive Oxygen Species in the Mechanism of Cytotoxic Action of Gold And Silver Polyacrylates on Tumor Cells
摘要
The possible role of the formation of intracellular reactive oxygen species in the cytotoxic effect of gold (aurumacryl) and silver (argacryl) polyacrylates on tumor cells (MCF-7 cell culture) was studied. For this purpose, the effect of the antioxidant N-acetyl cysteine, known as a free radical scavenger, on the cytotoxic effect of drugs and on the value of the specific reactive oxygen species marker was investigated. Argacryl was found to have a higher cytotoxic activity than aurumacryl, with an IC50 coefficient of 55 and 300 μg/ml, respectively, at 24 h exposure. It has been shown that the generation of reactive oxygen species is one of the key mechanisms in realizing the cytotoxic effect of aurumacryl, while the cytotoxic effect of argacryl is not associated with the production of intracellular reactive oxygen species in tumor cells under the influence of the drug. The presented results indicate that gold and silver polyacrylates, being active cytotoxic agents, have significant differences in the mechanism of action due to the nature of the metals contained in the preparations, which is in good agreement with the data we obtained earlier.
Biophysics. 2025;70(4):742–748
742–748
Genotoxicity of Nitroprusside As a Nitrosonium Cation Donor
摘要
The genotoxicity of sodium nitroprusside on human MCF-7 mammary gland adenocarcinoma cells was studied using the neutral comet method and the contribution of the nitrosonium ion (NO+) to the genotoxicity of sodium nitroprusside was determined. Genotoxicity was assessed by the yield of double-stranded DNA breaks after incubation of a cell culture with the agent for 1.5 hours. The genotoxicity of NO+ in sodium nitroprusside was determined after the procedure of reducing sodium nitroprusside using sodium dithionite, which converts nitroprusside from a NO+ donor to a NO only donor. It has been shown that sodium nitroprusside induces double-stranded DNA breaks in MCF-7 cells after 1.5 hours. This ability of nitroprusside does not depend on the stage of the cell cycle: the proportions of damaged cells in the G0/G1 and G2/M+S stages are 29 ± 7% and 27 ± 6%, respectively. As a result of 90-minute incubation with 100 μM of sodium nitroprusside, the proportion of cells severely damaged in the form of double-stranded DNA breaks is 25−30%, which is close to the proportion of non-viable cells according to the results of the MTT test at 24 h and 48 h of incubation (22 ± 4%). Sodium dithionite, by removing the toxic effect of NO+, protected MCF7 cells from the genotoxic effects of nitroprusside, which indicates the involvement of NO+ in the formation of double-strand breaks.
Biophysics. 2025;70(4):749–756
749–756
Stochastic Modeling of Energy Balance in MCF-7 Breast Cancer Cells Taking into Account Transposon Activity and Different Methylation States
摘要
Cancer cells exhibit increased activity of mobile genetic elements (transposons). A possible anticancer strategy involves exploiting the energy costs associated with abnormal activity of these elements to create conditions of energy starvation within the cell and initiate cell death programs. Here, we propose a stochastic model of energy balance in a cell population considering the energy expenditure associated with retrotransposition of LINE-1 and SINE mobile elements. Parameter values in the model were derived from published data and new experimental measurements of ATP quantities in MCF-7 cells under normal and hypomethylation conditions. Numerical stochastic simulations generated distributions of variables representing the number of mRNA molecules, proteins participating in principal energy-intensive cellular processes, and the number of active LINE-1 and SINE retrotransposons in the genome. Energy expenditure distributions across major cellular processes were also calculated under stationary conditions. Results show that low-energy costs linked to retrotransposition of mobile elements under normal conditions rise considerably upon perturbation of model parameters. These findings could inform practical scenarios influencing energetically mediated initiation of cell death programs in cancer cells through activation of mobile elements.
Biophysics. 2025;70(4):757–770
757–770
Self-Protection of Cells From Damage: Is This Atavistic Mechanism Activаted during the Development of Various Forms of Cancer?
摘要
The review analyzes the hypothesis of the retained ability of various specialized mammalian cells to protect themselves from lethal damage by reactivating the protective atavistic mechanism of cellular plasticity. The development of such protection is accompanied by the transition of differentiated cells from an oxygen-dependent to an oxygen-independent type of metabolism. This transition increases the threshold of cell resistance to death under cancer-inducing damaging effects. At the same time, the level of cell differentiation decreases, and embryonic markers appear. Such immature cells are necessary for the regeneration of damaged tissues. However, the regeneration programs of the embryo and the adult body differ significantly. As a result, the process of cellular redifferentiation would be forced to develop not in embryonic conditions but in “nonhealing wound” conditions, in which increases the risk of cancer initiation.
Biophysics. 2025;70(4):771–779
771–779
Complex systems biophysics
Binuclear Dinitrosyl Iron Complexes with Cysteine Inhibite the Development of Experimental Tumor
摘要
Binuclear dinitrosyl iron complexes with cysteine (B-DNIC-Cys), which are donors of nitrosonium cations (NO+), exhibit high antitumor activity when exposed to a formed tumor weighing 0.42 grams (12 days after transplantation), causing a 90% inhibition of tumor growth for 11 days and a 9.3-fold increase in the time of tumor mass doubling compared to the control (Lewis lung carcinoma). With early initiation of the complex administration − the next day after tumor transplantation – any noticeable effect on the tumor growth rate was not observed. It is assumed that the detected difference in the antitumor action of dinitrosyl iron complexes with cysteine depending on the tumor size is due to different ratios between the level of immunocompetent cells (macrophages) that selectively transfer these complexes and retain this ability, and the concentration of tumor cells that accept the complexes. With late initiation of the administration of dinitrosyl iron complexes with cysteine, this ratio increases due to a decrease in the number of tumor cells accessible to immunocompetent cells: it is limited to cells localized only in the peripheral (“superficial”) layer of the tumor.
Biophysics. 2025;70(4):780–786
780–786
Dihydroquercetin Normalizes Glucose Levels and Suppresses Oxidative Stress in the Aorta of Alloxan-Treated Rats
摘要
Pathological changes in blood vessels in diabetes are determined by oxidative stress. The effect of flavonoids on oxidative stress in blood vessels in diabetes has not been studied. In this work, we investigated the effect of flavanonol dihydroquercetin on blood glucose levels, the activity of angiotensin-converting enzyme, and the formation of reactive oxygen species in the aorta of rats with alloxan-induced diabetes. The activity of the angiotensin converting enzyme in the aortic segments was determined by the hydrolysis of hypuryl-L-histidylL-leucine, and the formation of reactive oxygen species was evaluated by the oxidation of dichlorodihydrofluorescein. It has been shown that dihydroquercetin reduces blood glucose levels, angiotensin-converting enzyme activity, and formation of reactive oxygen species in the aorta of diabetic rats to the values of these parameters in the aorta of control rats. Dihydroquercetin also normalizes the glucose tolerance test in diabetic rats. The effects of dihydroquercetin disappear after stopping its consumption. Thus, dihydroquercetin may be useful for the treatment of diabetes, but its consumption should be continuous.
Biophysics. 2025;70(4):787–793
787–793
Effect of Quercetin on Radiosensitivity and Adaptive Response in Mice
摘要
The work is devoted to the study of action of quercetin on radiosensitivity and induction of radiation adaptive response according to the criterion of cytogenetic damage in bone marrow cells under irradiation of mice with low and medium doses of X-rays. It was found that a single intraperitoneal administration of quercetin at a dose of 27.9 mg/kg leads to a significant increase in the radioresistance of mice to X-ray radiation at a dose of 1.5 Gy 5 and 24 h after injection, but not 20 min and 1 h, and does not change the value of adaptive response. Administration of quercetin at a concentration of 279 mg/kg 1 h before irradiation increased the radiosensitivity of mice but resulted in the disappearance of adaptive response. The involvement of oxidative stress levels and heat shock proteins at different stages of induction and formation of adaptive response depending on quercetin concentration is discussed.
Biophysics. 2025;70(4):794–803
794–803
Should Wistar Laboratory Rats Be Used in Experimental Studies on Visual Image-Related Learning?
摘要
A new method has been developed that allows rats to use visual rather than olfactory or tactile information when searching for food. It has been found that visually impaired white Wistar rats are not well suited for experimental studies on learning related to visual images. There is no linear relationship between the time of foraging after 96 hours of fasting.
Biophysics. 2025;70(4):804–808
804–808
Medical biophysics
The Effect of Gel Materials Based on Collagen and Taxifolin Derivatives on the Healing of Burn Wounds Induced by Acetic Acid
摘要
The aim of the work was to evaluate the effect of gel materials containing pentaglutarate of taxifolin and a conjugate of taxifolin with glyoxylic acid on the healing of skin wounds caused by acetic acid. It was shown that collagen materials containing polyphenols accelerated re-epithelialization and formation of granulation tissue compared with the control (collagen alone). The data obtained indicate that taxifolin derivatives can be considered as promising agents that not only cross-link collagen molecules, but also have a wound-healing effect. In turn, materials based on collagen and these polyphenols can be considered as dual purpose materials: as wound-healing agents and as a delivery system of biologically active substances to the area of injury.
Biophysics. 2025;70(4):809–817
809–817
Discussions
The XXI Century: Study of the Semantics of Languages of Describing Interactions of Competing Biosystems and the Principle of Complementarity of the Language of Theology to the Language of Natural Sciences
摘要
It has been shown that when two biosystems compete with each other, their struggle can intensify, which leads to uncertainty of the final result. When describing these phenomena, instead of binary logic (there is no third), ternary logic appears. In the interval between “Yes” and “No” there is a distance, which is filled with an additional “Possible” option, implemented with different probability values depending on its position on the “Yes”–“No” scale. The same phenomenon is typical for quantum theory, which implements one of two events. Various languages used to describe such phenomena are considered.
Biophysics. 2025;70(4):818–832
818–832