Репозиторий Университета

The heme in the active center of peroxidases reacts with hydrogen peroxide to form highly reactive intermediates, which then oxidize simple substances called peroxidase substrates. Human peroxidases can be divided into two groups: (1) True peroxidases are enzymes whose main function is to generate free radicals in the peroxidase cycle and (pseudo)hypohalous acids in the halogenation cycle. The major true peroxidases are myeloperoxidase, eosinophil peroxidase and lactoperoxidase. (2) Pseudo-peroxidases perform various important functions in the body, but under the influence of external conditions they can display peroxidase-like activity. As oxidative intermediates, these peroxidases produce not only active heme compounds, but also protein-based tyrosyl radicals. Hemoglobin, myoglobin, cytochrome c/cardiolipin complexes and cytoglobin are considered as pseudo-peroxidases. Рeroxidases play an important role in innate immunity and in a number of physiologically important processes like apoptosis and cell signaling. Unfavorable excessive peroxidase activity is implicated in oxidative damage of cells and tissues, thereby initiating the variety of human diseases. Hence, regulation of peroxidase activity is of considerable importance. Since peroxidases differ in structure, properties and location, the mechanisms controlling peroxidase activity and the biological effects of peroxidase products are specific for each hemoprotein. This review summarizes the knowledge about the properties, activities, regulations and biological effects of true and pseudo-peroxidases in order to better understand the mechanisms underlying beneficial and adverse effects of this class of enzymes. View Full-Text

Purpose

The interaction between malignant cells and surrounding healthy tissues is a critical factor in the metastatic progression of breast cancer (BC). Extracellular vesicles, especially exosomes, are known to be involved in inter-cellular communication during cancer progression. In the study presented herein, we aimed to evaluate the role of circulating plasma exosomes in the metastatic dissemination of BC and to investigate the underlying molecular mechanisms of this phenomenon.

Methods

Exosomes isolated from plasma of healthy female donors were applied in various concentrations into the medium of MDA-MB-231 and MCF-7 cell lines. Motility and invasive properties of BC cells were examined by random migration and Transwell invasion assays, and the effect of plasma exosomes on the metastatic dissemination of BC cells was demonstrated in an in vivo zebrafish model. To reveal the molecular mechanism of interaction between plasma exosomes and BC cells, a comparison between un-treated and enzymatically modified exosomes was performed, followed by mass spectrometry, gene ontology, and pathway analysis.

Репликативный полипротеин 1а вируса желтухи свеклы (ВЖС) содержит консервативные домены лидерной папаин-подобной протеиназы (РСР), метилтрансферазы (MTR) и РНК хеликазы (HEL). Центральный район (central region, CR) между MTR и HEL ранее считали «вариабельным». Нами проведен компьютерный анализ CR, который позволил выявить новый консервативный домен между позициями 1287-1390 (здесь и далее приводится нумерация аминокислотных остатков белка 1а вируса желтухи свеклы, BYV), сохраняющийся у всех представителей рода Closterovirus. Этот домен содержит 4 предсказанных альфа-спиральных участка (альфа А – D) и три строго консервативные позиции – глютамат-1291, пролин-1380 и аргинин-1384. Кроме того, биоинформатический анализ позволил предсказать амфипатическую спираль в позициях 1368-1380 (входящую в состав участка альфа D). Гидрофобный домен CR-2 (позиции 1305-1494 белка 1а), вызывающий при экспрессии в растениях реструктуризацию эндоплазматического ретикулюма и образование подвижных глобул диаметром ~1 мкм, включает участки альфа В, С и D. Установлено, что экспрессия в растениях слитных белков CR-2:GFP и GFP:CR-2 вызывает сходный «глобулообразующий» фенотип, т.е. N-концевое или C-концевое положение маркера GFP в слитном белке не влияет на переформатирование мембран эндоплазматического ретикулюма. Проведен делеционный анализ CR-2 BYV. Показано, что делеционные варианты 1355-1494 и 1325-1484 сохраняют фенотип дикого типа (образование глобул и реструктуризация ЭР вокруг ядра клетки). Варианты 1375-1484, 1368-1484 и 1368-1432 индуцировали образование глобул, но утрачивали способность к реструктуризации ЭР. Внесение замен гидрофобных аминокислотных остатков на остатки серина и глицина в «минимальном» делеционном мутанте 1368-1432 блокировало образование глобул. Предложена рабочая гипотеза о влиянии консервативной амфипатической спирали 1368-1385 в белке 1а BYV на ремоделирование мембран ЭР растительной клетки и создание репликативных платформ при клостеровирусной инфекции.

Autophagy is an evolutionary conserved intracellular catabolic process of vital importance to cell and tissue homeostasis. Autophagy is implicated in the pathogenesis of atherosclerosis but participating cells, molecular mechanisms and functional outcomes have not been fully elucidated. T-cadherin, an atypical glycosylphosphatidylinositol-anchored member of the cadherin superfamily of adhesion molecules, is upregulated on smooth muscle cells (SMCs)¹ in atherosclerotic lesions. Here, using rat and murine aortic SMCs as experimental models, we surveyed the ability of T-cadherin to regulate autophagy in SMCs during serum-starvation stress. Ectopic upregulation of T-cadherin in SMCs resulted in augmented autophagy characterized by increased autophagic flux, LC3-II abundance and autophagosome formation. Analysis of signal transduction pathway effectors and use of specific pharmacological inhibitors demonstrated that T-cadherin-associated enhancement of the autophagic response to serum-deprivation was dependent on MEK1/2/Erk1/2 activation and independent of PI3K/Akt/mTORC1, reactive oxygen species or endoplasmic reticulum stress. T-cadherin upregulation on SMCs conferred a survival advantage during prolonged serum-starvation which was sensitive to inhibition of MEK1/2/Erk1/2 by PD98059 or UO126 and to blockade of autophagy by chloroquine. Loss of T-cadherin expression in SMCs diminished autophagy responsiveness and compromised survival under conditions of serum-starvation. Overall our findings have identified T-cadherin as a novel positive regulator of autophagy and survival in SMCs.

The goal of this study was to find genes that encode cytoskeletal proteins that are potential candidates for the role of triggers in cell mechanosensitivity in the fruit fly. Centrifugation was used to simulate the hypergravity effects (2g group); the constantly changing orientation of the larvae in the gravity field was performed in order to simulate the effects of microgravity (0g group) for 1.5, 6, 12 and 24 h. mRNA levels of different genes that encode the components of both tubulin and actin cytoskeleton were assessed by qRT-PCR. In the 0g group the mRNA levels of beta-tubulin and Msps were reduced after 1.5 h of the exposure and remained unchanged until 12 h, while they exceeded the control level after 24 h. The mRNA level of chaperonin containing T-complex 1 polypeptide subunits recovered earlier: after 6 and 12 h of the microgravity exposure. At the same time, the hypergravity effect led to more significant changes in the mRNA level of TCP1 complex components compared with those of tubulin and Msps. The mRNA level of beta-actin isoforms under micro- and hypergravity was decreased up to 12 h of the exposure, however, it remained reduced under microgravity conditions, while it recovered (Act87E) and even exceeded (Act57B) the reference level under hypergravity conditions. The mRNA level of supervillin was almost unchanged. Under microgravity conditions the mRNA level of fimbrin was decreased (it recovered by the 24 h time point), while the mRNA level of alpha-actinin was significantly increased by the 12 h time point of the exposure and after 24 h it was reduced to the control level. In contrast, under hypergravity conditions the mRNA level of fimbrin initially increased, and after 24 h it dropped below the control, while the mRNA level of alpha-actinin was significantly reduced, and after 24 h it was higher than the reference level. Similar results were obtained earlier in the experiments in rodents, but similar dynamics were observed for alpha-actinin isoforms 1 and 4, although no changes were observed for fimbrin. Since Drosophila melanogaster has no alpha-actinin isoform 4, it is hypothesized that its role in the cell is played by fimbrin.

В области изучения нейробиологии униполярных депрессивных расстройств (УДР) перспективными считаются нейровизуализационные методы, особенно позитронно-эмиссионная томография (ПЭТ) и функциональная магнитно-резонансная томография (фМРТ). В статье приводится обзор современных нейровизуализационных данных, касающихся структурно-функциональных особенностей головного мозга у лиц, страдающих УДР. Результаты отдельных исследований представлены в зависимости от особенностей методов их проведения (состояние покоя, выполнение когнитивных и эмоциональных тестов) и соотнесены с основными нейробиологическими концепциями развития депрессивных расстройств. Отдельно рассмотрены возможности нейровизуализационных исследований для оценки и прогнозирования результатов антидепрессивной терапии.

Цель исследования. Изучение связи между генами иммунной системы и депрессией, а также ее эндофенотипами (невротизм и личностная тревожность) при ишемической болезни сердца (ИБС). Материал и методы. Исследование проведено в группе мужчин с ИБС с депрессией (78 человек) и без нее (91 человек), а также у здоровых добровольцев мужского пола (127 человек). Изучены полиморфизмы генов интерлейкина-4 (IL-4 –589C/T), интерлейкина-6 (IL-6 –174G/C), фактора некроза опухолей-α (TNF-α –308G/A) и С-реактивного белка (CRP –717A/G). Результаты. Обнаружена ассоциация полиморфизма IL-6 –174 G/C с депрессией, коморбидной ИБС (р=0,01; ОШ=2,3 ДИ 95% 1,2—4,3), которая выражалась в повышении частоты высокоэкспрессивного аллеля G в группе больных с депрессией. Полиморфизм IL-4 –589C/T был ассоциирован с ИБС: частота генотипа СС IL-4 –589C/T была выше в группе больных по сравнению с контрольной группой независимо от наличия депрессии (р=0,007; ОШ=2,1 ДИ 95% 1,2—3,4). Полиморфизмы TNF-α –308G/A и CRP –717A/G не были ассоциированы с депрессией при ИБС. Значимых различий в выраженности невротизма и личностной тревожности у носителей различных генотипов по локусам IL-4 –589 C/T, IL-6 –174 G/C, TNF-α –308 G/A, CRP –717A/G выявлено не было. Заключение. Ассоциация полиморфизма IL-6 –174G/C с депрессией, коморбидной ИБС, согласуется с данными литературы о роли IL-6 в развитии депрессии у кардиологических больных.

Objective. To assess antioxidant therapy (ascorbic acid (AA), Cytoflavin) prescribed as part of the standard treatment scheme based on clinical and morphological data in cerebral infarct. Materials and methods. The study was performed from 2010 to 2014 in eight vascular centers in the Russian Federation. A total of 373 patients with acute ischemic stroke in the carotid basin were studied. Group 1 consisted of 132 patients who received 5% AA solution at a daily dose of 20 ml; group 2 consisted of 113 patients receiving the antioxidant Cytoflavin at a daily dose of 20 ml for 10 days; group 3 consisted of 108 patients receiving Cytoflavin for 20 days, the dose being decreased to 10 ml from day 11 to day 20. Patients’ status was evaluated using a set of clinical, laboratory, and instrumented methods. Results and conclusions. Analysis of CT scan results obtained on treatment days 1 and 21 showed that Cytoflavin led to significant regression of the volume of cerebral ischemia, by an average factor of 1.5–1.7. No significant morphological changes were seen in the AA-treated group; among Cytoflavin-treated patients there was a two-fold reduction in the proportion of patients in which the volume of cerebral ischemia increased during the period 1–21 days. In patients with initial assessments of at least 14 points on the NIH scale, Cytoflavin treatment for 20 days promoted more marked improvements in neurological, functional, and cognitive status than seen in patients given infusions for 10 days.

Background Urethral reconstruction is one of the great surgical challenges for urologists. A cell-based tissue-engineered urethra may be an alternative for patients who have complicated long strictures and need urethral reconstruction. Here, we demonstrated the feasibility of using autologous urine-derived stem cells (USCs) seeded on small intestinal submucosa (SIS) to repair a urethral defect in a rabbit model. Methods Autologous USCs were obtained and characterized, and their capacity to differentiate into urothelial cells (UCs) and smooth muscle cells (SMCs) was tested. Then, USCs were labeled with PKH67, seeded on SIS, and transplanted to repair a urethral defect. The urethral defect model was surgically established in New Zealand white male rabbits. A ventral urethral gap was created, and the urethral mucosa was completely removed, with a mean rabbit penile urethra length of 2 cm. The urethral mucosal defect was repaired with a SIS scaffold (control group: SIS with no USCs; experimental group: autologous USC-seeded SIS; n = 12 for each group). A series of tests, including a retrograde urethrogram, histological analysis, and immunofluorescence, was undertaken 2, 3, 4, and 12 weeks after the operation to evaluate the effect of the autologous USCs on urethral reconstruction. ResultsAutologous USCs could be easily collected and induced to differentiate into UCs and SMCs. In addition, the urethral caliber, speed of urothelial regeneration, content of smooth muscle, and vessel density were significantly improved in the group with autologous USC-seeded SIS. Moreover, inflammatory cell infiltration and fibrosis were found in the control group with only SIS, but not in the experimental autologous USC-seeded SIS group. Furthermore, immunofluorescence staining demonstrated that the transplanted USCs differentiated into UCs and SMCs in vivo. Conclusions Autologous USCs can be used as an alternative cell source for cell-based tissue engineering for urethral reconstruction.

The discovery and development of effective antihypoxic drugs is an important issue in modern experimental and clinical pharmacology. Complexes of zinc containing imidazole cycles as ligands are promising candidates for the design of novel drugs, including pharmacotherapeutic tools for patient’s protection under conditions of oxygen deficiency. Herein, we report antihypoxic activity of zinc complexes with N-alkenylimidazoles, and, specifically, a novel drug Acyzol, which can be used as efficient antidote after poisoning by carbon monoxide and other combustion products.

The present study investigates the hepatoprotective effect of a novel zinc-containing drug acyzol in comparison with silymarin, a medicinal extract of milk thistle (Silybum marianum). The hepatoprotective effect was studied in 40 albino nonlinear male rats in a model of toxic liver injury induced by intragastric administration of carbon tetrachloride. Both drugs were diluted in water and administered intragastrically at doses 10 mg/kg (acyzol) and 100 mg/kg (silymarin) for 10 days twice daily, after development of clinical toxic hepatitis. Biochemical and functional indicators of the liver parenchyma demonstrated that both drugs reduced mortality, normalized the body and relative liver weight, reduced intensity of cytolytic, cholestatic, and mesenchymal inflammatory syndromes, and restored liver function. The study demonstrates that acyzol and silymarin have comparable hepatoprotective effect, thus, providing a rationale for the use of acyzol in complex therapy of toxic hepatitis and hepatosis.

One the current challenges of modern hepatology is to find new approaches to stimulate liver regeneration and to find new methods for liver disease treatment. Cell therapies, which are based on using regional stem cells for disease treatment, are under active development. However, studies, devoted to their transplantation, are currently scarce. In recent years, hepatic stellate cells are considered to be hepatic stem cells. It is known that activated hepatic stellate cells can transdifferentiate into myofibroblasts and lead to liver fibrosis. The aim of our work was to study the influence of native and activated hepatic stellate cells in vivo by lead nitrate injection after transplantation into partial hepatectomized rats, which is considered to be a classical model to study liver regeneration. Injection of 2-acetylaminofluorene (AAF), which selectively eliminates hepatocyte proliferation, was used to understand the hepatic stellate cells role in liver regeneration process better. Our results suggest that transplanted native and activated hepatic stellate cells can differentiate into hepatocyte-like cells and positively influence liver regeneration without inducing liver fibrosis.

The TRPV1 receptor plays a significant role in many biological processes, such as perception of external temperature (above 43°C), inflammation development, and thermoregulation. Activation of TRPV1 leads to the pain occurrence and decrease in the body temperature, while inhibition of this receptor can lead to an increase in the temperature. The TRPV1 peptide modulators from sea anemone Heteractis crispa extract (APHC1 and APHC3) have been previously characterized as molecules, which generated a pronounced analgesic effect and a decrease in the body temperature in experimental animals. Using the combined APHC1 and APHC3 amino acid sequences, we have prepared a hybrid peptide molecule named A13 that contains all residues potentially important for the activity of the peptide precursors. Biological tests on animals have shown that the hybrid molecule not only combines the analgesic properties of both peptides but, unlike the peptide precursors, also raises the body temperature of experimental animals.

Изучено влияние лектинов растительного происхождения на цитотоксическую активность мононуклеаров периферической крови (МНПК) здоровых доноров. Установлено, что лектин гороха вызывает статистически значимый цитотоксический эффект МНПК по отношению к клеткам колоректального рака.

Бронхиальная астма - мультифакторное заболевание, в основе которого лежат генетическая предрасположенность и агрессивное воздействие различных аллергенов. Заболевание сопровождается такими симптомами, как кашель, дистанционные свистящие хрипы, одышка. Однако данные симптомы сопровождают и бронхообструктивный синдром (БОС), который наблюдается у детей в возрасте 5 лет и младше в связи с инфекциями верхних дыхательных путей, которые часто встречаются в этой возрастной группе. При оказании помощи ребенку с бронхиальной обструкцией необходимо оценить тяжесть БОС до лечения. В педиатрии для купирования остро возникающих нарушений бронхиальной проходимости используют ß2-агонисты, антихолинергические препараты и их комбинацию.

Цель работы — совершенствование диагностики и лечения односторонних параличей возвратных гортанных нервов с преходящим рефлекторным спазмом функционирующей голосовой складки. Проведено обследование и лечение 49 больных (46 женщин и 3 мужчин) в возрасте от 21 года до 75 лет с односторонним параличом возвратного гортанного нерва и преходящим рефлекторным спазмом функционирующей голосовой складки, возникшим вследствие операции на щитовидной железе. Для диагностики и объективизации результатов лечения проводились электромиографический тест на скрытую тетанию, исследование уровня ионизированного кальция крови и видеоларингостробоскопия. Лечение включало дыхательную гимнастику, рефлексотерапию (новокаиновые блокады зон Захарьина—Геда для гортани, аурикулотерапию), медикаментозную терапию (витаминно-кальциевая терапия, миорелаксанты и седативные препараты), фонопедию. У всех 49 больных был восстановлен достаточно громкий и звучный голос, а также нормализовано дыхание и прекращены или минимизированы приступы рефлекторного кашля и ларингоспазмы. Ни одному больному в дальнейшем не потребовалось проведение трахеотомии.