Репозиторий Университета

© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Astrocytes, a class of morphologically and functionally diverse primary homeostatic neuroglia, are key keepers of neural tissue homeostasis and fundamental contributors to brain defence in pathological contexts. Failure of astroglial support and defence facilitate the evolution of neurological diseases, which often results in aberrant synaptic transmission, neurodegeneration and death of neurones. In Alzheimer’s disease (AD), astrocytes undergo complex and multifaceted metamorphoses ranging from atrophy with loss of function to reactive astrogliosis with hypertrophy. Astroglial asthenia underlies reduced homeostatic support and neuroprotection that may account for impaired synaptic transmission and neuronal demise. Reactive astrogliosis which mainly develops in astrocytes associated with senile plaque is prominent at the early to moderate stages of AD manifested by mild cognitive impairment; downregulation of astrogliosis (reflecting astroglial paralysis) is associated with late stages of the disease characterised by severe dementia. Cell-specific therapies aimed at boosting astroglial supportive and defensive capabilities and preventing astroglial paralysis may offer new directions in preventing, arresting, or even curing AD-linked neurodegeneration.

© 2019, Springer Science+Business Media, LLC, part of Springer Nature. Objectives. To study the expression of various neurotransmitter transporters (glutamate, aspartate, lactate, choline) in cultures of astrocytes from different part of the brain (cortex, hippocampus, and brainstem) in rats aged three and 11 days. Materials and methods. An experimental study was performed using 24 Rattus norvegicus rats aged three (n = 12) and 11 days (n = 12). High-throughput sequencing results were analyzed. Results. Expression of the glutamate and aspartate transporters in the brainstem in three-day-old rats was greater than in other areas, though the reverse pattern was seen in rats aged 11 days. Expression of the lactate transporter with age was identical to that in the cortex. Conclusions. The data obtained here demonstrated the nature of neuroastrocyte relationships and the role of astrocytes in the process of signal transmission. The results of the study, carried out using original methods of investigating neurotransmitter transporters, allow them to be recommended for monitoring the processes of neurogenesis and neurohomeostasis, including in cerebrovascular and neurodegenerative diseases.

© 2018, University of Kragujevac, Faculty of Science. All rights reserved. Two sets of reactants for modelling neurogenesis (SRMN) were developed based on the designed and tested genetic structures of lentiviral vectors. SRMN-1 contains the genetic construct LVV-GFAP-GCaMP3 and is intended for cellspecific transduction in astroglia cells. SRMN-2 contains the genetic construct LVV-PRSx8-TN-XXL and is intended for the phenotype-specific transduction in neurons. The present study examined SRMN-1 and SRMN-2 samples and assessed their efficiency in vitro and in vivo in Norvegicus rats. Specificity to particular cell types for all SRMN samples exceeded 97%. The number of induced signalling cascades was determined via activation of intracellular ingsignalling cascades in neurons and astrocytes (purinergic receptors and β-adrenoceptors). The results demonstrated dynamic recording of fluorescent signals and a two-fold increase in intensity after addition of the activator in all samples. The experimental SRMN samples revealed successful and stable transfection of catecholaminergic neurons and astrocytes, data on transfection efficiency, specificity of the developed genetic structures of SRMN, and calcium dynamics in transfected neurons and astrocytes.

© 2017, Springer Science+Business Media New York. Previous studies have indicated that paracrine factors (conditioned medium) increase wound closure and reduce reactive oxygen species in a traumatic brain injury in vitro model. Although the beneficial effects of conditioned medium from human adipose tissue-derived mesenchymal stem cells (hMSCA-CM) have been previously suggested for various neurological diseases, their actions on astrocytic cells are not well understood. In this study, we have explored the effect of hMSCA-CM on human astrocyte model (T98G cells) subjected to scratch assay. Our results indicated that hMSCA-CM improved cell viability, reduced nuclear fragmentation, attenuated the production of reactive oxygen species, and preserved mitochondrial membrane potential and ultrastructural parameters. In addition, hMSCA-CM upregulated neuroglobin in T98G cells and the genetic silencing of this protein prevented the protective action of hMSCA-CM on damaged cells, suggesting that neuroglobin is mediating, at least in part, the protective effect of hMSCA-CM. Overall, this evidence suggests that the use of hMSCA-CM is a promising therapeutic strategy for the protection of astrocytic cells in central nervous system (CNS) pathologies.

© 2018, Media Sphera Publishing Group. All rights reserved. The well apparent signs of the proliferative reaction and activity of the nucleolus organizer in astrocytes within the zone of injury and at its periphery are considered to be the indicators of the participation of these cells in all the phases of the inflammatory and reparative processes associated with the brain injury. The objective of the present study was the evaluation of the changes in the number of the nucleoli in the nuclei of astrocytes during the acute post-traumatic period following the craniocerebral injury. A total of 26 cases of death of the men and women at the age from 36 to 50 years caused by the craniocerebral trauma were available for the examination. The tissue samples were stained with hematoxylin and eosin, based on the use of the Perls’ Prussian blue staining protocol or by means of the AgNOR staining technique. The astrocytes in the regions immediately adjacent to the sites of brain injury were shown to undergo areactive necrosis during the first hours after the damage had been inflicted. The evaluation of the changes in the astrocytes required taking into consideration the influence of autolysis on the character of the signs being identified. The increase of the number of points in the astrocytes in which RNA replication occurs within days 2—4 after the injury can be accounted for by the accumulation of the granules containing silver in the cell nuclei. The cross reactions between hemosiderin and RNA await further investigations. It is concluded that the methods employed in this study may be of diagnostic significance for the purposes of forensic medical histology if used in the combination with other specialized techniques for determining the prescription of the craniocerebral injuries. The combination of the morphological and functional studies opens up the promising prospects for the investigations into the necrotic and proliferative processes in astrocytes associated with brain injuries of different origin.

© 2018, Media Sphera Publishing Group. All rights reserved. The objective of the present study was the development of the additional forensic medical criteria for the diagnostics of the intravitality and prescription of the burning injury making use of the morphological changes in the cerebellar cortex. A total of 82 cases of the death from the second- and third a, b-degree flame burns in 63 men and 19 women at the age from 20 to 65 years were available for the analysis. The condition of the cerebellar cortex was evaluated within 0 to 72 hours after the trauma had been inflicted. The routine histological staining technique using hematoxylin and eosin were employed as well as the Nisslin staining carried out in the combination with the immunohistochemical reaction based on the application of the antibodies against the glial fibrillary acidic protein (GFAP). In the case of death during the acute period after the burning injury, the histological study revealed a characteristic complex of the morphological features including the acute swelling of neurons, the increasing expansion of perivascular and pericellular spaces, as swell as hyperoxyphilia of microglia. The astrocytes of cortical II—III layers proved highly sensitive to tissue hypoxia as appears from their reaction with anti-GFAP antibodies. It is concluded that the results of the evaluation of the blood supply of the cerebral hemisphere cortex with the use of immunohistochemical methods may be helpful as the additional criteria for the purpose of forensic medical documentation of intravitality and prescription of the burning injury.

© Team of authors, 2018. Objective. To investigate the expression of transporters of different neurotransmitters (glutamate, aspartate, lactate, choline) in the culture of astrocytes isolated from different regions of the brain (cortex, hippocampus and brainstem) in 3- and 11-day rats. Material and methods. An experimental study was performed on 24 3-(n=12) and 11-days (n=12) old rats (Rattus norvegicus). The results of high-performance sequencing were analyzed. Results. The expression of glutamate and aspartate transporters in the brainstem of 3-day rats was higher than in other regions, however, an opposite effect was observed in 11-day rats. The expression of lactate transporters with age became identical to those of the cortex. Conclusion. The data demonstrate the particular qualities of neuro-astrocytic connections and the important role of astrocytes in signal transmission. Results of the study performed by using genetic methods developed by the authors for the study of neurotransmitter transporters make it possible to recommend these methods to control the neurogenesis and neurohomeostasis, including in cerebrovascular and neurodegenerative diseases.

© 2018 Irina Nikolaevna Dominova, Vitaly Anvarovich Kasymov, Ekaterina Vladimirovna Silina, Victor Aleksandrovich Stupin, Natalia Nikolaevna Shusharina and Maksim Vladimirovich Patrushev. A fragment of the research project devoted to the development of genetic control of exocytosis is presented in the work, which can further ensure the success of targeted therapy of various diseases, including neurodegenerative ones. For the purpose of specific transfection of intracellular cascades in astrocytes in vivo, we have developed an experimental sample of the reagent kit. The latter represents lentiviral genetic construction LVV-GFAP-Case12. The results of testing of experimental samples of the reagent kit for specific transfection of astroglial cells are presented with the purpose of targeted control of intracellular cascades in vivo on acute slices of different parts of the brain in adult Wistar rats. We selected regions of interest with cells expressing calcium indicator Case12 and responsible for ATP application by >2-fold amplification of fluorescence. We have developed instructions for using the reagent kit for specific transfection of astroglial cells with the purpose of targeted control of intracellular cascades.

© 2018 by the authors. A recently discovered key role of reactive oxygen species (ROS) in mitochondrial traffic has opened a wide alley for studying the interactions between cells, including stem cells. Since its discovery in 2006, intercellular mitochondria transport has been intensively studied in different cellular models as a basis for cell therapy, since the potential of replacing malfunctioning organelles appears to be very promising. In this study, we explored the transfer of mitochondria from multipotent mesenchymal stem cells (MMSC) to neural cells and analyzed its efficacy under normal conditions and upon induction of mitochondrial damage. We found that mitochondria were transferred from the MMSC to astrocytes in a more efficient manner when the astrocytes were exposed to ischemic damage associated with elevated ROS levels. Such transport of mitochondria restored the bioenergetics of the recipient cells and stimulated their proliferation. The introduction of MMSC with overexpressed Miro1 in animals that had undergone an experimental stroke led to significantly improved recovery of neurological functions. Our data suggest that mitochondrial impairment in differentiated cells can be compensated by receiving healthy mitochondria from MMSC. We demonstrate a key role of Miro1, which promotes the mitochondrial transfer from MMSC and suggest that the genetic modification of stem cells can improve the therapies for the injured brain.