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The process of apoptosis is known that play an important role in cellular homeostasis, and the altered cell death may lead to development of pathological disorders. Evolving autoimmune conditions, in particular, rheumatoid arthritis, are associated with decreased rates of apoptosis as a form of programmed cell death. The aim of this study was to evaluate expression of activation and proliferation markers on T lymphocytes during initiation of apoptotic cell death under the conditions of “cell neighborhood” in healthy individuals and patients with rheumatoid arthritis. Patients and methods. The study was performed with blood samples of the patients with rheumatoid arthritis (RA) and healthy women of comparable age. During the study, we conducted experiments aimed to identify the in vitro influence of non-stimulated apoptosis-induced cells, as well as aCD3-and dexamethasone (Dexa)-stimulated apoptosis-induced cells upon autologous T lymphocytes cultured under physiological conditions. Development of a “cell neighborhood” model, i.e., co-cultures of CFSE-T cells subjected to incubation under crowding condition and depletion of the culture medium which is the most physiological variant of apoptosis activation, and CFSE+autologous cells placed in the complete culture medium, has revealed some relationships. We have revealed an opportunity of secondary induction of early and late apoptosis by means of humoral and cellular components of autologous cell culture subjected to activation apoptosis. We determined the features of apoptosis in unstimulated, as well as aCD3-and dexamethasone-stimulated cultures, compared with controls. There were no differences in these parameters of apoptosis between RA patients and healthy people for all variants of cultures. An increased proportion of viale cells was found in the CFSE-culture of patients with RA when compared to donors. The donor group had more lymphocytes with activation parameters CD25+, CD69+and low level of proliferation marker Ki-67 than patients. In contrast to healthy, the RA patients demonstrated a significantly increased expression of Ki 67 in T lymphocytes when co-culturing CFSE-and CFSE+cells. An increased number of living cells in apoptotic cultures of patients with RA relative to healthy people, in absence of significant differences in the parameters of apoptosis and activation markers in dynamics, as well as pattern of changes in the Ki-67+cell contents suggested a contribution of the non-autonomous effects of apoptosis to cellular homeostasis in RA patients.

The review considers the properties of polyploid giant tumor cells a new target for the development of cancer therapy. Various number of polyploid giant tumor cells are detected in almost all human solid tumors. Their number increases under the influence of hypoxia, radiation, and after chemotherapy. Previously, these cells were not considered to be worth studying as they do not proliferate and eventually die as a result of one of the cell death mechanisms action. Recent data have demonstrated that polyploid giant cells can give rise to daughter cells that possess tumorigenicity and are characterized as stem tumor cells. Giant tumor cells and daughter cells are involved in the processes of metastasis, recurrence, drug resistance formation and radio-resistance of tumors. The search is under way for molecular targets that could prevent the appearance or contribute to the elimination of previously formed polyploid giant tumor cells. The combination of traditional therapy that causes the death of proliferating tumor cells and allows their elimination, with the use of tools that could prevent the appearance of resistant polyploid giant cells and their daughter cells, can be the key to the effective treatment of malignancies.

Mitochondria are intracellular organelles in eukaryotic cells that participate in bioenergy metabolism and cell homeostasis, including ATP generation through electron transport and oxidative phosphorylation in combination with oxidation of metabolites by the tricarboxylic acid cycle and fatty acid catabolism via β-oxidation. the production of reactive oxygen species, as well as the initiation and implementation of apoptosis. Mitochondria play a crucial role in cellular energy metabolism and the regulation of programmed cell death. mitochondria activate numerous signaling pathways associated with cell death. Mitochondria have the ability to control the activation of programmed cell death by regulating the translocation of proapoptotic proteins from the intermediate space of mitochondria to the cytosol. This is the reason for the emergence of a new discipline — mitochondrial medicine. The review examined and analyzed scientific publications on the role of mitochondria in the life support of transformed cells, the study of their functioning and structurally functional dysfunctions, as part of mitochondrial medicine. Mitochondrial medicine is a developing discipline whose significance stems from the central function of mitochondria in the production of adenosine triphosphate, the generation of reactive oxygen species, and cell death due to necrosis or apoptosis. Consequently, mitochondrial dysfunction plays an important role in the pathophysiology of cancer, many other common diseases and side effects of drugs. Perhaps the combined use of modulators of mitochondrial metabolism and antitumor therapy will contribute to the emergence of a new direction in antitumor treatment, which will significantly increase the effectiveness of cancer treatment.

Apoptosis is the leading mechanism of pancreatic β-cell destruction in type 1 diabetes mellitus (T1DM). Assessment of activation apoptosis in response to stimulation with mitogen or a specific antigen is considered more significant when studying apoptosis markers in peripheral blood mononuclear cells to clarify the role of programmed cell death in pathogenesis of various diseases, since the role of apoptosis in immune response is increased in activated cells. It has been established that the stimuli that activate resting Tlymphocytes initiate apoptotic death of activated T lymphocytes. Therefore, detection of spontaneous apoptosis only is not very informative. In addition, determination of cell sensitivity to apoptosis induction makes it possible to identify relations of pathological process to the enhancement or weakening of this sensitivity. The key point in the T1DM initiation is apoptosis resistance of activated autoreactive T lymphocytes, that migrate from bloodstream to the pancreas and take an active part in destruction of the pancreatic insular structures. Despite long studies of T1DM pathogenesis, the exact causes of resistance of effector T cell clones to apoptosis remain unclear. There are no facts that answer the question: to what extent is the ability of T lymphocytes of peripheral blood to enter into apoptosis associated with severity and duration of the disease. In this regard, the aim of the study was to evaluate the effectiveness of in vitro activation-induced apoptosis of T lymphocytes in the patients with T1DM, depending on the state of compensation and duration of the disease. The features of activationinduced apoptosis have been studied in cultures of peripheral blood mononuclear cells (PBMC) in the patients with T1DM. Phytohemagglutinin (PHA) and insulin were used as apoptosis inducers. Increased in vitro sensitivity of PBMC to activation-induced apoptosis was revealed in T1DM patients. The strongest apoptotic response to PHA was detected in cases of T1DM decompensation. Considering predominantly Tcells to undergo apoptosis in response to PHA stimulation, one may speak about high sensitivity of activated T lymphocytes to induced apoptosis in the patients with T1DM. The highest level of activation-induced apoptosis in response to insulin stimulation was revealed in the compensation phase of T1DM. We have found that the intensity of spontaneous and activation-induced apoptosis correlates with decompensation of the disease and the degree of β-cells secretory function disorder. In fact, strong direct correlation was observed between the percentage of hypodiploid cells and blood concentration of glucose, and the inverse correlation was shown between the number of apoptotic cells and serum levels of C-peptide. The data obtained are in accordance with the modern concept of T1DM immunopathogenesis, which includes a development of autoimmune diseases associated not only with enhanced apoptosis of target cells, but also with a defect in phagocytic clearance of apoptotic cells due to impaired efferocytosis, i.e., phagocytosis of apoptotic cells. Thus, the maximal increase in spontaneous and activation-induced apoptosis levels of peripheral blood lymphocytes during the DM-1 decompensation is explained not only by the hyperglycemia effects, but also by the secondary immune response to the so-called “late apoptotic” or “secondary necrotic” β-cells, due to their ineffective phagocytic clearance.

In recent decades, the methods based on the cell technologies have become more relevant for medical and pharmaceutical research. In this paper, weconsidered the BioStation CT using for continuous in vivo observation of Ehrlich ascitic carcinoma cell culture under the influence of two active substances in different concentrations (from 1.25 to 20 mg/l). As a result of the carcinoma cells condition monitoring for 4.5 days it was shown that substance No 2 does not affect the cell viability while substance No 1 causes the carcinoma cell death, and this active substance effect is dose-dependent. Photodocumentation at two-hour intervals allowed us to research differences in the rate of cell destruction (intensive disintegration in the first day with further stabilization of the living cells number or gradual cell death throughout the experiment), as well as differences in the time of 50 % mortality reaching. Thus in the study it was demonstrated that due to the fact that the BioStation CT combines the properties of a CO2 -incubator and a microscope this device is promising for toxicological studies and significantly expands the detection possibilities of processes occurring with living cells for a sufficiently long time period making possible further analysis of the cell behavior characteristics throughout the experiment, and that is fundamentally different from the systems allowing only the final result fixation of long-term active substance exposure.

Тhe protein TRIM16 is involved in key intracellular processes, such as proliferation, cell differentiation and programmed death, including intrinsic and extrinsic apoptosis, autophagy-dependent cell death and immunogenic cell death. The TRIM16 protein acts the proteins TPD43, Gli-1, RARβ, Snail components and MAPK signaling pathway, cadherins, caspases and is also associated with the regulation of the immune system via direct and indirect mechanisms. The influence of TRIM16 protein on the pathogenesis of hormone-dependent tumors is well-known. Further study of the TRIM16 role in the development and progression of malignant neoplasms will form the basis for the development of new methods for predicting the course of the malignant process.

The paper presents an overview of the structure and functions of caspase group enzymes. The main stages and ways of development of programmed cell death - apoptosis were demonstrated. The mechanisms of inhibition and activation of caspasesand their role in cell apoptosis are demonstrated. The different stages of caspase activation in the body are still insufficiently studied. At present, the structure, properties, key points of the functioning and regulation of caspases in the body have been studied in detail, but at the molecular and cellular levels it is not enough to directly regulate their activity. Modern studies of the effect of artificially created substances of different nature on these enzymes, in turn, open up prospects for further search for methods of their regulation, which in turn would allow using the knowledge gained in the treatment of oncological, autoimmune and neurodegenerative diseases.

Apoptosis is defined as a highly regulated form of programmed cell death with typical morphological and biochemical features. A variety of factors, including heavy metals, may influence the intensity of programmed cell death. The aim of the work was to simulate apoptosis in an in vitrosystem under the conditions of stable strontium exposure. The children’s population consuming drinking water with high strontium (Sr2+) content (n = 49) was observed. The level of lymphocyte apoptosis was determined with flow cytometry technique, by means of labeled annexin V-FITC conjugate (AnnV-FITC) and propidium iodide (PI) staining. AnnV-FITC+PI- cells were regarded as early apoptotic forms, whereas late apoptotic and/or necrotic cells were AnnV-FITC+PI+. The isolated leukocytes were incubated with Sr2+ at a concentration of 7.0 mg/l, the maximal permitted concentration (MPC) for water of aqueous objects, for 4 hours at 37 ºC. Expression of CD95 and p53 apoptosis markers was performed by flow cytometry using labeled monoclonal antibodies.In vitroexposure to strontium was associated with significantly decreased expression of apoptosisregulating factors, i.e., membrane marker CD95 and intracellular transcription protein p53, 1.56- and 1.68-fold, respectively. Meanwhile, we revealed a significantly (4.68-fold) decreased amounts of AnnV-FITC+PI--cells, as well as a statistically significant (1.35-fold) increase of the AnnV-FITC+PI+-cells. Moreover, the amounts of AnnV-FITC+ PI--lymphocytes in all samples were below the physiological ranges and control values. The number of samples with higher contents of AnnV-FITC+PI+-lymphocyte exceeding the established standards and control values, was 30.8%. Thus, it has been experimentally proven that strontium, at a concentration corresponding to MPC for water objects may significantly inhibit cell death along apoptotic pathways, with switching to necrotic cell death mechanisms, according to phosphatidylserine contents, as detected by annexin V binding test. The data have revealed an ability of strontium to have a significant effect upon the parameters of regulation and maintenance of cellular homeostasis, by influencing the apoptosis intensity, due to shifting a balance towards necrosis and reducing expression of apoptosis-regulating factors. The results of this study may be used in order to identify some marker indexes of immune disorders potentially induced by external influence of strontium upon human health under specific environmental factors.

Данная работа посвящена оценке способности некоторых абиотических и биотических стрессирующих факторов индуцировать программируемую клеточную гибель (ПКГ) в тканях проростков ячменя Hordeum vulgare L. В качестве абиотических факторов выступали хлорид натрия, хлорид алюминия, дефицит калия в среде выращивания и кратковременный тепловой шок. В качестве биотического фактора использовался раствор хитозана, имитирующего грибное заражение в тканях растения. Факторы были выбраны среди наиболее важных стрессоров, которым подвергаются посевы ячменя при культивировании на полях РФ, а также исходя из современных экологических проблем, грозящих существенным снижением урожайности данного злака. Результаты экспериментальных воздействий, проведенных в данной работе, анализировались с помощью методик выделения ДНК из корней и листьев ячменя и электрофоретической визуализацией в агарозном геле. Оценка способности эффекторов приводить к программируемой клеточной гибели производилась на основании одного из важнейших симптомов ПКГ, а именно - формирования межнуклеосомных разрывов геномной ДНК специализированными нуклеазами. При индукции нуклеазной активности происходило образование смеси фрагментов ДНК, что выявлялось по появлению характерной «лесенки» в агарозном геле. Установлено, что хлорид натрия в диапазоне концентраций от 50 до 500 мМ в течение 24 ч инкубации не индуцирует ПКГ в клетках корней проростков ячменя сортов Donaria и Донецкий-8. Хлорид алюминия в диапазоне концентраций 0,1-1 мМ при длительном воздействии (от 3 до 48 ч) не приводит к межнуклеосомной фрагментации ДНК в клетках корней проростков ячменя сортов Donaria и мутанта clo f2 3613. Дефицит калия в среде выращивания не индуцирует ПКГ в клетках корня 7 суточных проростков ячменя. Кратковременный тепловой шок индуцирует ПКГ, сопровождающуюся олигонуклеосомной фрагментацией ДНК, в клетках корня проростков ячменя. Элиситор хитозан, имитирующий биотический фактор, вызывает межнуклеосомную фрагментацию ДНК в клетках корня ячменя только при длительной инкубации в течение 7 суток. Программируемая клеточная гибель играет существенную роль во множестве важных процессов, необходимых для роста и развития растений. Несмотря на это, на сегодняшний день ПКГ остается явлением, не до конца охарактеризованным на цитологическом и молекулярно-биохимическом уровне. В связи с увеличением перспективности изучения ПКГ растений, становится особенно важным создание общепринятой классификации типов клеточной гибели, чего невозможно достичь без понимания механизмов действия провоцирующих клеточную гибель индукторов. На изучение индукторов ПКГ у растений и направлена данная работа., This work aimed at investigation of the ability of several abiotic or biotic stress factors to induce programmed cell death (PCD) in the tissues of barley (Hordeum vulgare L.) seedlings. The abiotic stress factors were elevated levels of sodium chloride or of aluminum chloride in the growth medium, potassium deficiency in the growth medium, or short-term heat shock. Solution of chitosan was used as an imitation of a fungal infection in plant tissues (a biotic stress factor). These stress factors were selected based on their prevalence and importance for the sustained growth of barley. The experiments presented in this study were based on DNA isolation techniques and subsequent visualization of the isolated DNA samples on agarose gels using electrophoresis. The ability of the stress factors to induce PCD was assessed on the basis of one of the main PCD symptoms, namely, the formation of internucleosomal cuts of genomic DNA by specific nucleases. The induction of the nuclease activity was visualized on agarose gels as a specific "ladder" of DNA fragments. It was found that sodium chloride in the concentration range from 50 to 500 mM during 24 h of incubation did not induce PCD in the root cells of Donaria and Donetsky-8 seedlings. Similarly, aluminum chloride in the concentration range of 0.1-1 mM with prolonged exposure (from 3 to 48 h) did not lead to internucleosomal DNA fragmentation in the root cells of Donaria and the clo f2 3613 mutant. Potassium deficiency in the growing medium did not induce PCD in root cells of 7 day seedlings of barley. On the contrary, short-term heat shock induced PCD in the barley root cells which was accompanied by oligonucleosomal DNA fragmentation. The elicitor chitosan caused internucleosomal DNA fragmentation in barley root cells after long-term incubation for 7 days. PCD plays a significant role in many important functions necessary for plant growth and development, but despite this, PCD remains not fully characterized at the cytological and molecular level. It becomes increasingly important to create a generally accepted classification of cell death types in plants, and this requires understanding the mechanisms of cell death induction and the steps leading to the different types of cell death.

Defects in programmed death of peripheral blood lymphocytes may result into autotolerance and chronic persistence of inflammatory reaction in rheumatoid arthritis. According to recent data, apoptosis is not an autonomous process, i.e., an excessive accumulation of cells in conjunction with a depleted medium leads to cellular excess, thus causing effect of cells already committed to apoptosis upon surrounding cells, by morphogenetic damage due to mechanical forces. Such effects are called compensatory proliferation or apoptosis-induced proliferation. Extracellular vesicles (ectosomes and apoptotic bodies) also have a negative effect on cultured cells, triggering their programmed apoptotic death. In turn, apoptosis can also be controlled by neighboring cells in non-autonomous manner. We conducted studies that allowed us to optimize methods aimed at the initiation of apoptotic cell death and to investigate the effects of apoptotic environment upon autologous cells under physiological conditions. The selected conditions in combination with a fluorescent labeling of lymphocytes and subsequent separate flow cytometric analysis allowed us to evaluate parameters of early apoptosis in subpopulations of peripheral blood T-lymphocytes in rheumatoid arthritis. In vitro studies of cells from the patients with rheumatoid arthritis allowed us to reveal a pronounced readiness of primary (CFSE) and secondary (CFSE+)-induced T lymphocytes for early apoptosis after stimulation with anti-CD3 antibodies. It was observed both against initial level of apoptosis, and when compared to cells induced for apoptosis. The obtained data suggest that stimulation of T lymphocytes with antibodies against CD3, and, as a result, an in vitro rise in cell proliferation rate leading to increased levels of early apoptosis not only among the cells directly receiving a proliferative stimulus, but also to increased effect of cellular and humoral components from anti-CD3-stimulated cultures upon normally proliferating lymphocytes. The transfer of an autologous apoptotic “aCD3” and dexamethasone-stimulated cultures, which were initially induced under conditions of cell overcrowding and medium exhaustion, was shown to activate the process of early apoptosis among normally proliferating cells. Glucocorticoids are known to serve as agents of cell death induced by activation. At pharmacological concentrations, glucocorticoids and their synthetic analogues stimulate endonucleases in activated lymphocytes. These enzymes destroy DNA in the internucleosomal regions thus resulting into cell apoptosis. The results obtained in present study suggest an opportunity of an in vitro early-stage apoptosis induction in T lymphocytes from the patients with rheumatoid arthritis, by means of cells subjected to activation-induced apoptosis.

Objective. To study the change of expression of TrkA, p75 receptors and their ratio on the human anaplastic astrocytoma, glioblastoma and medulloblastoma cells cultures exposed to nerve growth factor (NGF) and its combination with cisplatin or temozolomide, to establish participation of expression of the receptors in sensitivity tumor cells to NGF and its combinations with chemotherapeutical drugs. Materials and methods . In primary cell cultures of anaplastic astrocytoma, glioblastoma and medulloblastoma were studied: 1) cytotoxicity effects of nerve growth factor and its combination with cisplatin or temozolomide; 2) the expression of TrkA, p75 receptors and the its ratio by immunofluorescence; 3) correlation between expression of TrkA, p75 receptors, the its ratio and index of cytotoxicity of reagents. Results. It is found that the expression of the receptors and the relationship depends on the tumor type and reagents’ mechanism of action. Expression of TrkA and p75 receptors and their ratio correlated with sensitivity of anaplastic astrocytoma and glioblastoma cells to NGF and its combination with cisplatin or temozolomide. Conclusion. Relative expression of TrkA/p75 receptor, and its coefficient of correlation with index of cytotoxicity point to a mechanism (signaling pathway), on which there is cell death.

Цель исследования оценка токсичности кальцийфосфатных бионов (КФБ) и магнийфосфатных бионов (МФБ) для культур эндотелиальных клеток. Методика. Эндотелиотоксичность бионов изучена при помощи добавления равных концентраций МФБ или КФБ к: 1) разреженным или конфлюэнтным культурам иммортализованных венозных эндотелиальных клеток человека линии EA.hy 926 с последующим культивированием в течение 24 ч или 4 ч соответственно 2) конфлюэнтным культурам коммерческих первичных эндотелиальных клеток коронарной и внутренней грудной артерии человека с последующим культивированием в течение 24 ч. Эндотелиотоксические эффекты бионов оценивали при помощи сочетанного окрашивания клеток флюоресцентными красителями Hoechst 33342 и бромистым этидием, а также посредством колориметрического теста. Кроме того, методом проточной цитометрии оценивали пути и стадии гибели клеток вышеуказанных культур. Результаты. В отличие от МФБ, КФБ индуцировали гибель эндотелиальных клеток всех 3 линий путем апоптоза. Устойчивость культур к токсическому действию КФБ определялась степенью их конфлюэнтности (конфлюэнтные культуры более устойчивы чем разреженные) и типом клеточной линии (эндотелиальные клетки внутренней грудной артерии продемонстрировали большую устойчивость в сравнении с эндотелиальными клетками коронарной артерии). Заключение. Токсичность КФБ для культур эндотелиальных клеток специфична, то есть определяется их специфическим минеральным составом, а не общей для всех типов бионов корпускулярной природой. Добавление КФБ к конфлюэнтным культурам первичных артериальных эндотелиальных клеток и к иммортализованным венозным эндотелиальным клеткам вызывало их гибель, при этом экспозиция МФБ не оказывает значимого токсического действия. Эндотелиальные клетки внутренней грудной артерии менее чувствительны к воздействию КФБ в сравнении с эндотелиальными клетками коронарной артерии человека., Aim. To compare toxicity of calcium phosphate bions (CPB) and magnesium phosphate bions (MPB) for endothelial cells. Methods. To assess endothelial toxicity of the bions, we first added equal concentrations of either MPB or CPB to: 1) nonconfluent or confluent cultures of immortalized human venous endothelial cells EA.hy 926 with the exposure time of 24 h or 4 h, respectively 2) confluent cultures of commercially available primary human coronary artery and internal thoracic artery endothelial cells, with the exposure time of 24 h. Endothelial toxicity was then evaluated by combined Hoechst 33342 and ethidium bromide staining following fluorescence microscopy and by colorimetric cytotoxicity assay. In addition, we attempted to determine the pathway of bioninduced cell death utilizing flow cytometry. Results. In contrast to the MPB, CPB induced apoptosis of all studied endothelial cell lines. Resistance of endothelial cells to the CPB was defined by their confluence (confluent cultures demonstrated higher resistance), and cell type (internal thoracic artery endothelial cells were more resistant to the CPB as compared to the coronary artery endothelial cells). Conclusions. Endothelial toxicity of the CPB is defined by their specific mineral composition but not by their corpuscular nature, which is common for all nanoparticles. Addition of the CPB to the confluent cultures of primary human arterial cells and to immortalized human venous endothelial cells evoked their death. On the contrary, exposure to the MPB did not cause any toxic effects. Human internal thoracic artery endothelial cells are more resistant to the CPB in comparison with coronary artery endothelial cells., №1 (2019)

Цель исследования - изучение структурно-функциональных изменений нейронов сенсомоторной коры головного мозга белых крыс в норме и после 20-минутной окклюзии общих сонных артерий. Методика. С помощью световой (окраска гематоксилином и эозином, по Нисслю), флуоресцентной (окраска DAPI), иммунофлуоресцентной (нейронспецифическая енолаза - NSE) и электронной микроскопии была изучена нейроцитоархитектоника сенсомоторной коры (СМК) головного мозга белых крыс в норме (n =5) и в динамике - 1, 3, 7, 14, 21 и 30 сут.; после 20-минутной окклюзии общих сонных артерий (n =30). Согласно рекомендациям Nomenclature Committee on Cell Death (2009), проведено детальное описание и сравнение всех морфотипов измененных пирамидных нейронов СМК мозга белых крыс после острой ишемии. Морфометрический анализ проведен с помощью программы ImageJ 1.46. Результаты . Использование комплекса морфологических методов позволило классифицировать нейроны на основании четких структурных маркеров и доказать возможность апоптоза гиперхромных нейронов СМК после воспроизведения ишемии. Показано, что через 3 сут. в слое III 6-12% гиперхромных нейронов подвергалось апоптозу, 13,4-24,6% - коагуляционному некрозу, а остальные выходили из патологического состояния в отдаленном восстановительном периоде. Необратимо измененные клетки-тени составляли 11,5% (95% ДИ: 7,4-16,8%). Общая численная плотность пирамидных нейронов в течение 30 сут. постишемического периода в слое III СМК снижалась на 30,5% (95% ДИ: 24,2-38,7%), а в слое V - на 14,4% (95% ДИ: 9,9-20,0%). Заключение. Показана смешанная природа гибели нейронов - одновременное сочетание процессов некроза и апоптоза (парапоптоз). Однако основную роль в гибели нейронов играли процессы быстрого и отдаленного ишемического некроза., №2 (2018)

Programmed cell death (PCD) was first studied in eukaryotic organisms. This system also operates in the development life cycle of prokaryotes. The system PCD in microorganisms is activated a wide range of signals in response to the stresses associated with adverse environmental conditions or exposure to antibacterial agents. The results of numerous studies in the past decade allow considering the system PCD in prokaryotes as an evolutionary conservation of the species. These results significantly expanded understanding of the role of PCD in microorganisms and opened a number of important areas of research of the morphological and molecular genetic approaches to the study of death strategies for the survival in bacterial populations. The purpose of the review is to summarize the morphological and molecular genetic characteristics of PCD in prokaryotes which are real manifestations of the mechanisms of this phenomenon.

Apoptosis is a variant of programmed cell death. This term was introduced by Kerr et al. in 1972, but information on the important role of apoptosis of some cells in critical conditions has recently appeared. The review of literature considers the basic mechanisms of induction, development, and regulation of apoptosis. Based on a literature update, the authors analyze the role of apoptosis in the pathogenesis of various critical conditions: acute lung lesion (neutrophilic and epithelial hypotheses), sepsis, myocardial infarction, and ischemic stroke (apoptosis of tubular epithelial cells), hepatic dysfunction in sepsis, myopathies in critical conditions. The data of studies dealing with the effects of inhaled and non-inhaled anesthetics on the apoptosis of neurons of the brain and lymphocytes are given. The review of literature presents the options of therapeutic apoptosis modulation by pharmacological methods.

The present work provides results of a number of biotechnological studies aimed at creating cell lines and entire plants resistant to anaerobic stress. Developed biotechnological approaches were based on earlier fundamental researches into anaerobic stress in plants, so “Introduction” briefly covers the importance of the problem and focuses on works considering two main strategies of plants adaptation to anaerobic stress. Those are adaptation at molecular level where key factor is anaerobic metabolism of energy (true tolerance) and adapta-tion of the entire plant via formation of aerenchyma and facilitated transportation of oxygen (apparent toler-ance). Thus, sugarcane and wheat cells resistant to anaerobic stress were obtained through consecutive in vitro selection under conditions of anoxia and absence of exogenous carbohydrates. Tolerant wheat cells were used to regenerate entire plants of higher resistance to root anaerobiosis. It has been demonstrated that cells toler-ance to anoxia is significantly supported by their ability to utilize exogenous nitrate. Cells tolerance established itself at the genetic level and was inherited by further generations. Apart from that, other successful attempts to increase tolerance of plants to anaerobic stress by means of stimulation of glycolysis and overexpression of genes responsible for cytokinin synthesis and programmed cell death are also discussed. The presented data proved the notion of two main strategies of plants adaptation to anaerobic stress proposed earlier on the base of fundamental studies. KeyWordS anaerobic stress, growth index, in vitro cell selection, programmed cell death, transgenic plants, mi-tochondrial ultrastructure.abbreViationS PDC – pyruvate decarboxylase; ADH – alcohol dehydrogenase; ISPA- International Society for Plant Anaerobiosis.introductionAs plants are obligate aerobes, oxygen deficiency (hy-poxia) and especially its total absence (anoxia) cause dramatic ecological stress. Meanwhile plants often suf-fer from sudden molecular oxygen deprivation both under natural condition and as a result of human activ-ity. Most often plants are subject to oxygen depriva-tion on hydromorphic and flooded soils for the oxygen’s poor solubility and low diffusion rate in the water [1, 2]. nowadays, there are vast areas of hydromorphic soils in many countries [3–5]. It is believed that melting of permafrost and polar ice, together with ensuing rise of the world ocean level, may lead to a flooding of nu-merous regions of the planet. Oxygen scarcity is also observed in firm soils [6]. In this respect, roots and seeds of plants are the most vulnerable. In northern countries and countries with a moderate climate winter cereals and perennials can be damaged by ice crust, imperme-able to gas, that appears on the surface of soil in au-tumn and winter [7]. Anaerobic stress may damage and even lead to a total failure of crop and wildings thus causing considerable ecologic and economic losses. Problem of hypoxia and anoxia is also important in regard to long-term storage of agricultural commodi-ties like fruits, grain, vegetables [8]. In last decades anaerobic stress in plants has become a topical subject of study not only among physiologists and biochemists, but molecular biologists and geneti-cists as well. number of publications and ISPA confer-ences devoted to study of hypoxia and anoxia in plants is constantly rising. Anaerobic stress has been discussed in numerous special issues of international journals (see Annals of Botany (special section). 1994. V. 74. no 3. ed. Jackson M.B.; Annals of Botany (special Issue). 1997. V. 79. ed. Jackson M.B.; Annals of Botany (special section). 2002. V. 90. no 4. ed. Smirnov n.; Annals of Botany (spe-cial Issue). 2003. V. 91. eds Visser e., Voesenek L.A.c.J., Jackson M.B.; russian J. of Plant Physiology (Special

An influence of cold hardening (8 °С, 7 days) on the respiration intensity, the content of reactive oxygen species and DNA fragmentation in coleoptiles of maize etiolated seedlings of different ages and a possibility of the cold hardening to prevent execution of the cell death, induced by treatment with 10 mM H 2O 2 (for 4 hours) of seedlings have been studied. It has been shown that H 2O 2 induces total DNA fragmentation in coleoptiles of maize etiolated seedlings, and a preliminary cold hardening prevents this process.

Vitamin E derivatives are known to act as agents exhibiting cytotoxity against tumor cells. The effect of vitamin E succinate on human epidermoid carcinoma cell line A431 was investigated in this study using live imaging, immunocytochemistry, and transmission electron microscopy. α -Tocopheryl succinate-induced apop-totic cell death in A431 cells was shown to be both dose- and time-dependent. The hyperproduction of reactive oxygen species, changes in size, shape and ultrastructural characteristics of mitochondria followed by the release of cytochrome c from mitochondria to cytosol were observed. These results suggest that α -tocopheryl succinate induces apoptosis that occurs via the mitochondrial pathway. Mitochondria are shown to be crucial targets in α -tocopheryl succinate-induced caspase-dependent cell death in human carcinoma A431 cells.KEYWORDS α -tocopheryl succinate; apoptosis; mitochondrial pathway; ROS; cytochrome cABBREVIATIONS α -TS – α -tocopheryl succinate; ROS – reactive oxygen species; AI – apoptotic indexINTRODUCTIONMany researchers are now focusing on searching for anti-tumor agents that would selectively affect ma-lignant cells while being nontoxic to normal cells and tissues. Vitamin e derivatives are among such com-pounds.the term “vitamin e” is now used to refer to a large group of both the natural and synthetic compounds known as tocopherols and tocotrienols, as well as to the acetyl and succinyl derivatives of tocopherol. the biological effects of vitamin e are diverse and remain understudied. certain forms of vitamin e can be con-sidered as potential anti-tumor agents, since they can scavenge free radicals, suppress growth and induce differentiation in transformed cells, affect the course of the cell cycle, induce apoptosis, and activate the im-mune system [1–3].It has been shown that α-tocopherol exhibits virtually no anti-tumor activity, whereas a number of its deriva-tives, including vitamin e succinate (α-tocopheryl succi-nate, α-tS), exhibit antitumor properties. unhydrolized α-tS is a redox-silent compound ; however, as opposed to free α-tocopherol, it exhibits unique antiproliferative and proapoptotic properties [4]. α-tS can affect tumor cells in culture [5, 6], as well as human tumor xenografts in animal models and tumors induced by chemical can-cerogenes [7–11]. α-tS can induce cell death and cell cy-cle arrest [12, 13], inhibit angiogenesis [14], and protect the organism against ionizing radiation [15].Intracellular targets of α-tS in cell lines of different origins have been subjected to intense investigation in recent years. α-tS has been demonstrated to induce the apoptotic death of a number of tumor cells (breast cancer, malignant mesothelioma, neuroblastoma cells) via the mitochondrial pathway [16–21]. nevertheless, the mech-anisms of α-tS -induced apoptosis remain rather poorly understood. the effect of α-tS has been investigated on tumor cell lines of different origins. Skin neoplastic dis-eases are characterized by high malignancy and belong to poorly treatable tumors; however, there are almost no studies devoted to the effect of vitamin e derivatives on transformed keratinocytes thus far. Malignant skin diseases often have an unfavorable prognosis.Hence, the effect of α-tocopheryl succinate on hu-man epidermoid carcinoma A431 cells was investigated in this study.EXPERIMENTALCell culture and experimental procedureA431 cells (human epidermoid carcinoma) (Institute of cytology of the russian Academy of Sciences, russia) were cultured in a DMeM medium (Paneco, russia) supplemented with 10% fetal bovine serum (PAA Lab-oratories, Austria) and 80 mg/ml gentamycin (Paneco) at 37°c with 5% cO