Physiological Features of Erythrocytes in the Aging Organism
Elena Sergeevna Tkacheva, Ilya Nikolaevich Medvedev*, Nadezhda Viktorovna Vorobyeva, Valerii Panteleevich Kartashev, Galina Sergeevna Mal
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Elena Sergeevna Tkacheva Department of Epizootiology and Microbiology, Vologda State Dairy Farming Academy named after N.V. Vereshchagin, 160555, Vologda, Russia.
Ilya Nikolaevich Medvedev*, Valerii Panteleevich Kartashev Faculty of Medicine, Russian State Social University, 129226, Moscow, Russia.
Nadezhda Viktorovna Vorobyeva Department of Physical Education, South-West State University, 305040, Kursk, Russia. Laboratory of the physiology of digestion and interstitial metabolism, All-Russian Research Institute of Physiology, Biochemistry and Animal Nutrition - Branch of the Federal Scientific Research Center for Livestock - All-Russian Institute of Livestock named after Academician L.K. Ernst, 249013, Kaluga Region, Borovsk, Russia.
Galina Sergeevna Mal Department of Pharmacology, Kursk State Medical University, 305041, Kursk, Russia.
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*E-mail: [email protected]
Abstract
The progression of aging affects various blood parameters, which can weaken the viability of the body. Clarification of various aspects of this process requires additional observations, especially with the use of animals. The study was conducted on 43 healthy outbred male rats aged 24 months. Also, 32 healthy outbred male rats 3 months old, which formed the control group, were taken under observation. The examined 24-month-old rats showed standard aging phenomena. In their erythrocytes, there was an increase in lipid peroxidation caused by a weakening of the activity of their antioxidant defense. In the blood of two-year-old rats, there was a decrease in the level of erythrocyte-discocytes. This was accompanied in them by an excess content of erythrocytes in the blood, which had a changed shape to varying degrees. In rats of the older group, erythrocyte aggregation was increased, as indicated by an increase in the numberof erythrocytes that entered the aggregates in the blood and an increase in the number of most erythrocyte aggregates with a decrease in the level of free erythrocytes. For two-year-old rats, low content of erythrocytes-disconcytes in the blood and an excess number of erythrocytes with a modified shape, as well as an increase in their aggregation, are characteristics. An important reason for these changes is the weakening of the antioxidant protection of erythrocytes, leading to a pronounced activation of lipid peroxidation in them.
Keywords: Erythrocytes, Aging, Rats, Rheology, Physiology, Hematology
Introduction
Science recognizes aging as one of the most common processes in nature. It affects all structures of the body of living beings (Dontsov et al., 2010). The continuation of the development of biological science requires a detailed elucidation of the manifestations and mechanisms of the appearance and development of signs of aging, which is especially convenient to do during the experiment (Vatnikov et al., 2018). This is recognized as necessary for the further development of gerontology and biology (Kishkun, 2008).
The ongoing scientific research is increasingly aimed at studying in detail the main stages of the implementation of aging and the processes of formation of age-related pathology with a deep consideration of the mechanisms of gerontogenesis on various models (Klebanov et al., 2019). Modern researchers attach particular importance to monitoring various parameters of blood cells (Kulikov et al., 2020) and especially the most numerous group - erythrocytes (Zavalishina et al., 2018) in different conditions of the body (Zavalishina et al., 2019) and of course in the course of aging (Vakhtin, 2009). The significance of these studies is that aging affects the state of all cells in the body, as a rule, leading to a weakening of their work, with the occurrence of dysfunctions, and sometimes pathological processes.
Under conditions of aging, especially in the presence of obvious pathological manifestations, there is an excessive activity of platelets, which worsens many hematological parameters (Usha et al., 2019). The emerging situation weakens the implementation of microcirculation and lowers the level of metabolism in all organs (Bespalov et al., 2018; Vorobyeva et al., 2018). At the same time, the state of microrheological parameters of erythrocytes under aging conditions cannot be considered fully elucidated.
Rats remain one of the leading objects of research in gerontology. They test various hypotheses and carry out experimental effects on the body with different goals (Dontsov & Krutko, 2019). As a rule, various changes in morphology and physiology, including those associated with the development of aging, are monitored in rats. In this regard, the work aims to determine the degree of physiologically acceptable changes in the microrheological characteristics of erythrocytes in aging rats.
Materials and Methods
This work was carried out in accordance with ethical standards and fundamentals of humane work with laboratory animals, which are formulated in the European Convention for the Protection of Vertebrate Animals used in any experiments.
43 healthy outbred male rats at the age of 24 months were taken into work. During their lives, these animals did not get sick and did not take part in any acute or chronic experiments. 32 outbred healthy male rats, aged 3 months, were also taken into the study. They formed a control group. All rats were examined once.
The level of plasma lipid peroxidation was assessed in the course of determining the active substances contained in plasma using a kit manufactured by Agat-Med (Russia) and by the content of acyl hydroperoxides in plasma (Ashtiani et al., 2021; Ong et al., 2021). In all cases, the level of plasma antioxidant activity was determined (Abdaltif et al., 2021). The level of lipid peroxidation processes in erythrocyte structures was recorded by the content of malondialdehyde and acyl hydroperoxides in them. In rat erythrocytes, using the enzymatic method using a kit manufactured by Vitaldiagnostikum (Russia), the cholesterol content was determined, and the total content of phospholipids was determined by the amount of phosphorus in them. The ratio of cholesterol content in erythrocytes to phospholipids was calculated. The activity of erythrocyte catalase and superoxide dismutase was determined.
Surface features of red blood cells were determined by phase contrast microscopy. According to the shape of erythrocytes, they were divided into three groups: discocytes, reversibly altered erythrocytes, and irreversibly altered erythrocytes. The severity of erythrocyte aggregation was determined using a light microscope and a Goryaev camera. The number of erythrocyte aggregates, the number of erythrocytes that entered into aggregation, and the erythrocytes that remained free were assessed.
The results found during the study were processed statistically by calculating the Student's t-test and indicators of systemic multivariate analysis.
Results and Discussion
When examining aging rats, standard manifestations of aging were found. They consisted of a dulling of the coat, a weakening of the severity of appetite, and a decrease in interest in the outside world. In the control group, the appearance of the animals had no features.
The rats of the older group had high plasma levels of molecules of acyl hydroperoxides and molecules of substances capable of combining with thiobarbituric acid, which exceeded the control levels by 24.3% and 16.9%, respectively. The found increase in lipid peroxidation in aging rats occurred due to the weakening of the plasma antioxidant system to a level of 24.3 ± 0.47%, yielding to the level of the control group by 19.7% (Table 1).
Table 1. Dynamics of hematological parameters in observed rats
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Registered indicators |
A group of aging rats, M±m, n=43 |
Control group, M±m, n=32 |
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Level of acyl hydroperoxides in plasma, D233/1ml |
1.94±0.032 р<0.01 |
1.56±0.023 |
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The content of thiobarbituric acid-active products in plasma, µmol/l |
4.29±0.039 р<0.01 |
3.67±0.028 |
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Plasma antioxidant potential, % |
24.3±0.47 р<0.01 |
29.1±0.42 |
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Erythrocyte cholesterol level, µmol/1012 erythrocytes |
1.03±0.029 р<0.05 |
0.91±0.038 |
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The level of total erythrocyte phospholipids, µmol/1012 erythrocytes |
0.65±0.029 |
0.69±0.020 |
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Cholesterol/total erythrocyte phospholipids ratio |
1.58±0.036 р<0.01 |
1.32±0.032 |
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Number of erythrocyte acyl hydroperoxides, D233/1012 erythrocytes |
3.43±0.028 р<0.01 |
2.71±0.041 |
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The amount of malonic dialdehyde in erythrocytes, nmol/1012 erythrocytes |
1.14±0.036 р<0.01 |
0.88±0.027 |
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Erythrocyte catalase activity, IU/1012 erythrocytes |
7940.0±15.7 р<0.01 |
9920.0±9.5 |
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Erythrocyte superoxide dismutase activity, IU/1012 erythrocytes |
1660.0±6.11 р<0.05 |
1870.0±7.6 |
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The content of erythrocytes-discocytes, % |
73.0±0.52 р<0.05 |
85.1±0.53 |
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Number of reversibly altered erythrocytes, % |
17.9±0.41 р<0.01 |
9.3±0.26 |
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Number of irreversibly altered erythrocytes, % |
9.1±0.24 р<0.01 |
5.6±0.17 |
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The total number of all erythrocytes in the aggregate, cells |
47.9±0.12 р<0.01 |
36.5±0.09 |
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Number of aggregates, units |
12.3±0.10 р<0.01 |
8.5±0.10 |
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The number of free erythrocytes, cells |
222.0±0.69 р<0.05 |
251.3±0.32 |
Symbols: p – reliability of differences between the recorded indicators and the control group.
In rats of the older group, the amount of cholesterol in the composition of erythrocytes was increased with a slight decrease in the content of total phospholipids in them. This led to an increase in the ratio of cholesterol to total phospholipids in erythrocytes.
In older rats in the structures of erythrocytes, activation of lipid peroxidation was noted, which was caused by a decrease in the biological capabilities of their antioxidant system (Ahmed & Althanoon, 2022). The revealed changes in the levels of products resulting from lipid peroxidation in the composition of erythrocytes in rats of the older group were carried out as a result of a decrease in their antioxidant protection, and primarily due to a weakening of catalase and superoxide dismutase.
In rats of the older group, there was a significant decrease in the amount of disk-shaped erythrocytes in the blood (Abdaltif et al., 2021; Ahmed, 2021). At the same time, in the blood of these rats, there was an excess of erythrocytes having a changed shape. In rats of the older group, an increase in the number of erythrocytes included in the aggregates and an increase in the number of these aggregates in their blood was noted, with a simultaneous decrease in the number of erythrocytes that did not involved in aggregation.
The processing of the data found in the work by systemic multivariate analysis in older rats made it possible to calculate the value of the pro-aggregation potential of erythrocytes and the size of the disaggregation potential of erythrocytes in them, to determine the contribution of all indicators recorded in the work, and also to calculate the value of the erythrocyte total aggregation potential.
When calculating the pro-aggregation potential of erythrocytes in rats of the older age group, the average size of the erythrocyte aggregate (Pi=579.3), the content of erythrocyte aggregates in the blood (Pi=481.3), the number of erythrocytes that have an irreversibly changed shape (Pi=433.6) and the total number of erythrocytes included in the aggregates (Pi=411.6). The size of the weighted average pro-aggregation potential of erythrocytes, which comprehensively characterizes erythrocyte aggregation in rats of the older age group, was 0.109.
The most significant in the disaggregation potential of erythrocytes in rats of the older age group were the activity of erythrocyte superoxide dismutase (Pi = 526.4), the content of erythrocytes in their blood with a discoid shape (Pi = 524.3) and the biological capabilities of catalase (Pi = 518.7). The weighted average of the disaggregation potential of erythrocytes in aging rats, which generally characterized the functioning of the mechanisms that inhibit aggregation of erythrocytes, reached a value of 0.086, while the total aggregation potential of erythrocytes in these animals was 0.023.
In the pro-aggregation potential of erythrocytes in rats of the control group, the average aggregate size (Pi=452.6), the number of erythrocyte aggregates (Pi=437.0), the level of irreversibly changed erythrocytes (Pi=373.0) and the total number of erythrocytes that entered into the aggregate (Pi=362.6). The value of the weighted average of the pro-aggregation potential of erythrocytes in the control reached 0.095.
The most important in the disaggregation potential of erythrocytes in control rats was the level in their blood of erythrocytes with a discoid shape (Pi=617.5), the severity of the enzymatic capabilities of erythrocyte catalase (Pi=598.5) and superoxide dismutase (Pi=598.2). The value of the weighted average disaggregation potential of erythrocytes in control rats reached 0.098, while their total aggregation potential of erythrocytes was -0.003.
The development of all phenomena of aging can be considered a consequence of the complex simultaneous interaction of the hereditary program and the range of environmental effects on the body (Dyleva et al., 2023). From this point of view, one can also look at age-related changes in the rheological parameters of erythrocytes. They are very convenient to study in rats, which are a recognized physiological model. The life span of rats is short, and the development of the aging process in them is similar to that in other mammals, therefore the mechanisms and manifestations of aging revealed in this living object can be transferred to other mammals with some caution.
Aging under standard conditions in the observed rats was manifested by the appearance of some hematological disorders, which were established in our work at the age of 24 months of life. The authors consider their presence to be a consequence of the development of natural aging. In many ways, they are associated with the formation of membranopathies in blood cells caused by the aging process and external influences on the body.
With aging, the observed rats had a weakening of the antioxidant capacity of the blood, which led to an increase in the content of acyl hydroperoxides and substances capable of reacting with thiobarbituric acid, which inhibits metabolism in tissues. The resulting increase in the phenomena of lipid peroxidation in the liquid part of the blood leads to increased alteration of the vascular endothelium and outer membranes of blood cells (Kotova et al., 2017). This fully applies to their most numerous population, erythrocytes, which may exhibit various dysfunctions in the course of aging (Tabeeva, 2019). This situation can be significantly aggravated due to the development of hypoxia, which forms during aging, primarily against the background of the appearance of membranopathy in erythrocytes caused by an increase in cholesterol in them, a decrease in phospholipids and activation of lipid peroxidation due to a decrease in the antioxidant defense of erythrocytes (Dorontsev et al., 2022).
The current situation leads to the loss of some of the erythrocytes of their discoid shape, worsening the entire microcirculation in the capillary zone. Developing changes in the erythrocyte structure leads to an increase in their level in the blood with the reversible and irreversible transformation of the form (Yashkichev, 2018). In rats with signs of aging, the blood level of erythrocytes with signs of echinocytosis and stomatocytosis significantly exceeded that in the control group. In the future, their transformation inevitably leads to an increase in the number of erythrocytes in the blood, which are spheroechinocytes, spherostomatocytes, and spherocytes, which do not participate in gas exchange, which weakens metabolism (Karpov et al., 2020).
It can be thought that shape disturbances in a significant part of the erythrocyte population in the blood can be caused by damage to the intraerythrocytespectrin network, leading to changes in many erythrocytes of the optimal distance between adjacent spectrin strands.
The increase in erythrocyte aggregation found in older rats is caused by the development of changes in the charge of their surface with age due to degradation under the influence of lipid peroxidation activation of some of the glycoproteins located on it, which have a negative charge (Karpov et al., 2021). An increase in the synthesis of ionized oxygen species in the blood and, especially, in the erythrocytes of aging rats, even those kept under optimal conditions, is inevitable. This is accompanied by oxidative alteration of many membrane lociand changes in the optimal tertiary structure of various proteins in blood plasma. These changes stimulate the interaction of damaged blood proteins with free erythrocytes, activating the phenomena of their aggregation. The excess lipid peroxidation products present in this case accelerate the onset of erythrocyte aggregation as a result of the development of multiple oxidative damages to their membranes and inhibition of erythrocyte disaggregation processes by increasing the strength of the bond between erythrocytes in aggregates of any size (Mikhaylova et al., 2021).
The activation of erythrocyte aggregation phenomena in aging rats is also largely due to the increased action of catecholamines on their surface, the concentration of which in the blood increases very often during aging. This can be realized during the activation of erythrocyte α1-receptors with subsequent stimulation of the Ca2+-calmodulin system and involvement of erythrocyte phosphatidylinositols in the activation processes. Also, aggregation of erythrocytes increases in aging rats due to an increase in the functionality of α2-adrenergic receptors of erythrocytes. This leads to depression of the adenylate cyclase enzyme in them and an increase in the amount and activity of cytoplasmic Gi proteins. This situation contributes to a decrease in the amount of cytoplasmic cyclic adenosine monophosphate in erythrocytes and an increase in the flow of Ca2+ ions into them (Zavalishina et al., 2021). All this greatly enhances the aggregation of red blood cells directly in the bloodstream, causing several undesirable consequences.
An increase in the content of small erythrocyte aggregates in the blood of aging rats leads to an increase in the number of injuries to the internal endothelial lining of blood vessels. This increases the degree of expression of subendothelial structures in the blood, thereby stimulating the mechanisms of hemostasis and inhibiting hemocirculation in general (Zavalishina, 2020). An increase in the number of erythrocyte aggregates suspended in the blood impairs blood perfusion through the existing vasavasorum. This leads to a clear weakening of all types of metabolism in the walls of blood vessels, causing a significant decrease in the level of generation in endotheliocytes of substances that have disaggregation activity (Zdravomyslova, 2022) and are extremely important for hemocirculation (nitric oxide and prostacyclin).
Conclusion
In aging rats in the blood, there is a low level of erythrocytes having a discoid shapeand an increase in the number of their varieties with an altered surface. Also, their erythrocytes are characterized by an increased tendency to aggregate. This is largely due to an increase in the content of the ratio of cholesterol and phospholipids in the structures of erythrocytes and a weakening of the antioxidant capabilities of their structures, leading to the intensification of lipid peroxidation processes. This situation in the body of aging rats creates conditions for increased injury to the vascular endothelial layer, which makes elements of their subendothelium available to them and enhances the work of hemostasis. violations. They can exacerbate the manifestations of aging, closing the vicious circle: "senile changes - microrheological disorders."
Acknowledgments: The team of authors thanks the administration of th Vologda State Dairy Farming Academy named after N.V. Vereshchagin e for the opportunity to research its basis.
Conflict of interest: None
Financial support: None
Ethics statement: The study was approved by the local ethics committee of the Vologda State Dairy Farming Academy named after N.V. Vereshchagin on September 15, 2018 (protocol №11).
Abdaltif, A., Abdallah, M. D., Yagowb, M. Y., Mustafa, M. G., Alameen, T. A., Attar, A. O. G., Abdelgani, S. & Eltayeb, L. B. (2021). Transfusion related Hepatitis C virus antibodies and possible risk factors in healthy blood donors. Pharmacophore, 12(5), 32-37.
Ahmed, F. (2021). ficusbenghalensis bark extract shows blood pressure lowering effect in normotensive and angiotensin ii-induced hypertensive Rats. Pharmacophore, 12(5), 7-10.
Ahmed, R. J., & Althanoon, Z. A. (2022). Effects of Hydroxychloroquine on markers of oxidative stress and antioxidant reserve in rheumatoid arthritis patients. Journal of Advanced Pharmacy Education & Research, 12(3), 65-71.
Ashtiani, A. R. A., Galdavi, R., & Jafari, M. (2021). Investigating endurance training with ergometer bicycle in changes the plasma levels of chemerin on overweight women. Archives of Pharmacy Practice, 12(1), 50-54.
Bespalov, D. V., Kharitonov, E. L., Zavalishina, S. Yu., Mal, G. S., & Makurina, O. N. (2018). Physiological basis for the distribution of functions in the cerebral cortex. Research Journal of Pharmaceutical, Biological, and Chemical Sciences, 9(5), 605-612.
Dontsov, V. I., & Krutko, V. N. (2019). Is the treatment of age-related diseases an anti-aging therapy: the role of aging syndromes in the general scheme of the pathogenesis of aging. Clinical Gerontology, 25(9-10), 48.
Dontsov, V. I., Krutko, V. N., & Trukhanov, A. I. (2010). Antiaging medicine: fundamental principles. Moscow: KRASAND, 680.
Dorontsev, A. V., Vorobyeva, N. V., Kumantsova, E. S., Shulgin, A. M., Sharagin, V. I., & Eremin, M. V. (2022). Functional Changes in the Body of Young Men Who Started Regular Physical Activity. Journal of Biochemical Technology, 13(1), 65-71. doi:10.51847/X03w75Xldo
Dyleva, Yu. A., Belik, E. V., & Gruzdeva, O. V. (2023). Obesity and aging. General aspects. Russian Journal of Physiology, 109(3), 267-282.
Karpov, V. Y., Zavalishina, S. Y., Bakulina, E. D., Dorontsev, A. V., Gusev, A. V., Fedorova, T. Y., & Okolelova, V. A. (2021). The Physiological Response of the Body to Low Temperatures. Journal of Biochemical Technology, 12(1), 27-31. doi:10.51847/m1aah69aPr
Karpov, V. Yu., Zavalishina, S. Yu., Komarov, M. N., & Koziakov, R. V. (2020). The Potential of Health Tourism Regarding Stimulation of Functional Capabilities of the Cardiovascular System. Bioscience Biotechnology Research Communications, 13(1), 156-159. doi:10.21786/bbrc/13.1/28
Kishkun, A. A. (2008). Biological age and aging: the possibility of determining and ways of correction: A guide for doctors. Moscow: Geotar-Media, 973.
Klebanov, A. A., Morgunova, G. V., & Khokhlov, A. N. (2019). On the study of the patterns of aging and longevity in experiments with non-subcultured cell cultures. Clinical Gerontology, 25(9-10), 14-16.
Kotova, O. V., Zavalishina, S. Yu., Makurina, O. N., Kiperman, Ya. V., Savchenko, A. P., Skoblikova, T. V., Skripleva, E. V., Zacepin, V. I., Skriplev, A. V., & Andreeva, V. Yu. (2017). Impact estimation of long regular exercise on hemostasis and blood rheological features of patients with incipient hypertension. Bali Medical Journal, 6(3), 514-520. doi:10.15562/bmj.v6i3.552
Kulikov, E. V., Zavalishina, S. Y., Vatnikov, Y. A., Seleznev, S. B., Parshina, V. I., Voronina, Y. Y., Popova, I. A., Bondareva, I. V., Petrukhina, O. A., Troshina, N. I., et al. (2020). The effects of meldonium on microrheological abnormalities of erythrocytes in rats with obesity: An experimental study. Bali Medical Journal, 9(2), 444-450. doi:10.15562/bmj.v9i2.1150
Mikhaylova, I. V., Zavalishina, S. Yu., Zbrueva, Yu. V., Bakulina, E. D., Rysakova, O. G., & Eremin, M. V. (2021). Dynamics of General Functional Characteristics of an Individual in the Process of Chess Training. Journal of Biochemical Technology, 12(4), 61-66. doi:10.51847/a7DmaeQ9UD
Ong, A. G., Kumolosasi, E., Islahudin, F., Chan, S. Y., Lim, X. Y., Hanapiah, S. M., & Ahmat, A. N. M. F. (2021). Bloodstream Infections in Solid Tumor Malignancy: Risk Factors and Clinical Outcome. Archives of Pharmacy Practice, 12(3), 33-39.
Tabeeva, G. R. (2019). Neurocognitive aging and cognitive disorders. Journal of Neurology and Psychiatry named after C.C. Korsakov, 119(6), 160-167.
Usha, B. V., Zavalishina, S. Y., Vatnikov, Y. A., Kulikov, E. V., Kuznetsov, V. I., Sturov, N. V., Kochneva, M. V., Poddubsky, A. A., Petryaeva, A. V., & Glagoleva, T. I. (2019). Diagnostics of early dysfunctions of anticoagulant and fibrinolytic features of rats’ vessels in the course of metabolic syndrome formation with the help of fructose model. Bali Medical Journal, 8(1), 201-205. doi:10.15562/bmj.v8i1.923
Vakhtin, Yu. B. (2009). Dissymbiotic concept of aging (intracellular evolution is the cause of aging and death). Medical and Biological Problems of Life, 2(2), 5-16.
Vatnikov, Yu. A., Zavalishina, S. Yu., Seleznev, S. B., Kulikov, E. V., Notina, E. A., Rystsova, E. O., Petrov, A. K., Kochneva, M. V., & Glagoleva, T. I. (2018). Orderly muscle activity in elimination of erythrocytes microrheological abnormalities in rats with experimentally developed obesity. Bali Medical Journal, 7(3), 698-705. doi:10.15562/bmj.v7i3.739
Vorobyeva, N. V., Mal, G. S., Zavalishina, S. Yu., Glagoleva, T. I., & Fayzullina, I. I. (2018). Influence of physical exercise on the activity of brain processes. Research Journal of Pharmaceutical, Biological and Chemical Sciences, 9(6), 240-244.
Yashkichev, V. I. (2018). Cells pulsations as the living base and at the same time – mechanism of dehydration of cells and insenescence of the organism. Science and Peace, 5-2 (57), 24-28.
Zavalishina, S. Y., Karpov, V. Y., Zagorodnikova, A. Y., Ryazantsev, A. A., Alikhojin, R. R., & Voronova, N. N. (2021). Functional Mechanisms for Maintaining Posture in Humans during Ontogenesis. Journal Biochemical Technology, 12(1), 36-39. doi:10.51847/5LNdtyTcdH
Zavalishina, S. Y., Vatnikov, Y. A., Kulikov, E. V., Kubatbekov, T. S., Vilkovysky, I. F., Petrov, A. K., Tishchenko, A. L., Drukovsky, S. G., Zharov, A. N., & Grishin, V. N. (2019). Effect of a combination of arterial hypertension and insulin resistance on hemostasis activity. Bali Medical Journal, 8(1), 211-215. doi:10.15562/bmj.v8i1.1151
Zavalishina, S. Yu. (2020). Functional Activity of the Cardiorespiratory System and the General Level of Physical Capabilities Against the Background of Regular Physical Exertion. Bioscience Biotechnology Research Communications. 13(4), 2327-2331. doi:10.21786/bbrc/13.4/105
Zavalishina, S. Yu., Vatnikov, Yu. A., Kubatbekov, T. S., Kulikov, E. V., Nikishov, A. A., Drukovsky, S. G., Khomenets, N. G., Zaykova, E. Yu., Aleshin, M. V., Dinchenko, O. I., et al. (2018). Diagnostics of erythrocytes’ early microrheological abnormalities in rats with experimentallydeveloped obesity. Bali Medical Journal, 7(2), 436-441. doi:10.15562/bmj.v7i2.740
Zdravomyslova, E. A. (2022). Men and women: aging in the optics of a gender approach. Sociodigger, 3,5-6 (18), 16-26.
