INTRODUCTION:Adenylyl cyclase (AC) is an important enzyme that mediates stem cells' response to hormonal stimuli. Despite the fact that currently there are ten described isoforms of AC little is known about their individual significance in different aspects of stem cell functions control. This study focuses on elucidating the significance of AC isoforms in the control of multipotent mesenchymal stromal cells (MSCs) differentiation. We investigated changes in adenylyl cyclase expression (ADCY) during adipogenic and osteogenic differentiation of MSCs. Our results suggest that the expression only of ADCY1 elevates during MSCs' both osteogenic and adipogenic differentiations. RESULTS:We used the CRISPR/Cas9 D10A system to knock out the ADCY1 gene in MSCs. The ADCY1 knockout MSC cell line demonstrated reduced ADCY1 expression in the undifferentiated state compared to control cells. Moreover, ADCY1 expression in the ADCY1-KO cell line didn't increase during the differentiation process, which confirms the successful knockout. The ADCY1-KO cell line demonstrated an impaired differentiation potential in both adipogenic and osteogenic directions. However, the ability for adipogenic differentiation was restored by a direct PPARγ agonist addition. CONCLUSIONS:Our findings indicate that ADCY1 expression upregulation is critical for MSC differentiation into osteogenic and adipogenic lineages.
The global mental health study has revealed a steady increase in the prevalence of mental disorders worldwide. This trend reflects not only the improvements in diagnostics but also the global population ageing and the intensification of negative environmental impacts that provoke the manifestation of such disorders. One of such primary external causes for mental disorders is stress, which accompanies humans throughout their lives. Stressful exposure, particularly chronic stress, can alter the expression of genes involved in the development, maturation, and functioning of the nervous system, which in turn may provoke the manifestation of mental disorders in susceptible individuals. The effects of stress can explain the increasing prevalence of mental illnesses (depression, anxiety disorders), and their aggravation with age. Stress seems to have the greatest impact during critical periods of brain development: intrauterine and early postnatal stages. The molecular mechanisms mediating the impact of stress on the expression of genes crucial for brain development and function, as well as the list of genes involved, remain poorly understood. In this review, we have attempted to summarize the known information on the influence of stress on the activity of epigenetic modifiers and the state of the epigenome, the expression of target genes, brain development, and changes in behavioral patterns. Studying such mechanisms and the genes involved opens up opportunities for diagnosing mental disorders at a new methodological level and potentially offers new precision approaches to their therapeutic correction at the epigenomic level.
IntroductionGenetic technologies provide an opportunity to study the molecular basis of a wide range of hereditary pathologies, including mental disorders. Reproducing of potentially pathogenic genomic variants in cellular and animal models allows establishing their functional significance and possible mechanisms of involvement in the pathogenesis of certain disorders.MethodsIn this study, a genetic variant of urokinase type plasminogen activator (uPA, gene Plau) was modeled in mice using CRISPR/Cas genome editing tool, enabling a better understanding of the role of this molecule and its associated pathways in brain development. The protease uPA plays an important role in the directed migration of neural progenitors, glial, endothelial and immune cells, it participates in axon guidance and maturation of synaptic connections, activation of growth factors and degradation of the extracellular matrix. To study the contribution of the catalytic function of uPA to brain development, we have created for the first time a mouse line carrying the D277N (rs1243306395) mutation. We assessed social activity, anxiety, memory, problem-solving ability and stress resistance of these mice, as well as histological features of their brains.ResultsTimely and correct functioning of the Plau gene ensures adequate positioning of crucial cellular components in the developing nervous system. According to bioinformatic calculations, the D277N (corresponds to the human single nucleotide variant rs1243306395) substitution that happens due to C-to-T mutation in the murine Plau gene may impair the catalytic activity of the uPA protein. While retaining their ability to find solutions in the escape test, this mouse line is characterized by high levels of anxiety, impaired social behavior, slowed learning dynamics (spatial memory), and impaired adaptation to stressors. This behavioral pattern can potentially be interpreted as autism spectrum disorder Histological analysis of the brain and cerebral cortex in Plau-D277N mice revealed brain volume enlargement and cortical thickening of approximately 10-15% compared to wild-type mice.DiscussionIn this study, we draw attention for the first time to the genomic variant rs1243306395 in the Plau gene as a potential cause of autism spectrum disorder and propose the genetically modified Plau-D277N mouse line as a model object for studying the pathogenesis of this disorder. These models can also be used for the development and testing of promising therapeutic approaches and pharmacological agents.
The secretome of mesenchymal stromal cells (MSCs) can efficiently stimulate regeneration and therefore is a tempting remedy for “cell-free cellular therapy”. However, the usage of primary MSC cultures as secretome producers for translation studies has obvious obstacles, including the rapid aging of MSC cultures, the need for a large number of verified donors, and donor-to-donor variability of secretome content. MSCs immortalization makes it possible to overcome those limitations and to obtain secretome-producing cultures with a prolonged lifetime. However, the efficacy and safety of such secretomes are critical issues that limit their usage as therapeutic agents. In this study, we tested in large detail how the immortalization of MSC cultures affects the content, biological activity and safety of their secretome. MSCs immortalization via the overexpression of human TERT gene does not significantly alter the qualitative and quantitative composition of their secretome or its activity according to the results of proteomic analysis, ELISA, qPCR and functional tests in vitro. Moreover, we have demonstrated that the secretome of immortalized MSCs does not contain detectable amounts of telomerase and does not possess any transforming activity. Altogether, our data suggest that immortalized MSC cultures may become a reliable source for obtaining standardized active secretome in large-scale quantities for clinical use.
IntroductionImpaired function of brain morphogenic genes is considered one of the predisposing factors for the manifestation of psychiatric and cognitive disorders, such as paranoid schizophrenia (SCZ) and major depressive disorder (MDD). Identification of such genes (genes of neurotrophic factors and guidance molecules among them) and their deleterious genetic variants serves as a key to diagnosis, prevention, and possibly treatment of such disorders. In this study, we have examined the prevalence of genomic variants in brain morphogenic genes in individuals with SCZ and MDD within a Russian population.MethodsWe have performed whole-exome sequencing of 21 DNA samples: 11 from individuals with SCZ and 10 with MDD, followed by ARMS (Amplification-Refractory Mutation System) based screening of detected single nucleotide variants (SNVs) in larger groups: 102 for individuals with SCZ, 79 for those with MDD and 103 for healthy donors.ResultsWhole-exome sequencing has revealed 226 missense mutations in 79 genes (out of 140 studied), some of which occur in patients with psychiatric disorders significantly more frequently than in healthy donors. We have identified previously undescribed genomic variants in brain morphogenic genes: CDH2 (rs1944294-T and rs17445840-T), DCHS2 (rs11935573-G and rs12500437-G/T) and CDH23 (rs1227051-G/A), significantly associated with the incidence of SCZ and MDD in the Russian population. For some SNVs (rs6265-T, rs1944294-T, rs11935573-G, rs4760-G) sex-biased differences in their prevalence between SCZ/MDD patients and healthy donors was detected.DiscussionHowever, the functional significance of the SNVs identified has still to be confirmed in cellular and animal models. Once it is fulfilled, these SNVs have the potential to complement the diagnostic toolbox for assessing susceptibility to mental disorders. The data obtained indirectly confirm the importance of adequate brain structure formation for its correct functioning and preservation of mental health.
Genome editing technologies and their modifications are an indispensable tool for studying the functions of individual molecules, obtaining cell lines and animals with specified properties, and developing promising approaches to the therapy of previously untreatable diseases. This review covers various aspects of genome editing technologies: from their biological significance to the principles of their functioning and the most promising areas of application in basic and applied research. Particular attention is paid to discussing the limitations of genome editing technologies, as well as the legal and ethical aspects of their application to human genome modification. This review may be of interest to a wide range of readers, including researchers wishing to learn more about genome editing technologies and planning their practical application.
Multipotent mesenchymal stromal cells (MSCs) integrate hormone and neuromediator signaling to coordinate tissue homeostasis, tissue renewal and regeneration. To facilitate the investigation of MSC biology, stable immortalized cell lines are created (e.g., commercially available ASC52telo). However, the ASC52telo cell line has an impaired adipogenic ability and a depressed response to hormones, including 5-HT, GABA, glutamate, noradrenaline, PTH and insulin compared to primary cells. This markedly reduces the potential of the ASC52telo cell line in studying the mechanisms of hormonal control of MSC’s physiology. Here, we have established a novel immortalized culture of adipose tissue-derived MSCs via forced telomerase expression after lentiviral transduction. These immortalized cell cultures demonstrate high proliferative potential (up to 40 passages), delayed senescence, as well as preserved primary culture-like functional activity (sensitivity to hormones, ability to hormonal sensitization and differentiation) and immunophenotype up to 17–26 passages. Meanwhile, primary adipose tissue-derived MSCs usually irreversibly lose their properties by 8–10 passages. Observed characteristics of reported immortalized human MSC cultures make them a feasible model for studying molecular mechanisms, which regulate the functional activities of these cells, especially when primary cultures or commercially available cell lines are not appropriate.
Mental illness and cognitive disorders represent a serious problem for the modern society. Many studies indicate that mental disorders are polygenic and that impaired brain development may lay the ground for their manifestation. Neural tissue development is a complex and multistage process that involves a large number of distant and contact molecules. In this review, we have considered the key steps of brain morphogenesis, and the major molecule families involved in these process. The review provides many indications of the important contribution of the brain development process and correct functioning of certain genes to human mental health. To our knowledge, this comprehensive review is one of the first in this field. We suppose that this review may be useful to novice researchers and clinicians wishing to navigate the field.
Hyperlipidemia is a major risk factor for vascular lesions in diabetes mellitus and other metabolic disorders, although its basis remains poorly understood. One of the key pathogenetic events in this condition is mitochondrial dysfunction associated with the opening of the mitochondrial permeability transition (MPT) pore, a drop in the membrane potential, and ROS overproduction. Here, we investigated the effects of bongkrekic acid and carboxyatractyloside, a potent blocker and activator of the MPT pore opening, respectively, acting through direct interaction with the adenine nucleotide translocator, on the progression of mitochondrial dysfunction in mouse primary lung endothelial cells exposed to elevated levels of palmitic acid. Palmitate treatment (0.75 mM palmitate/BSA for 6 days) resulted in an 80% decrease in the viability index of endothelial cells, which was accompanied by mitochondrial depolarization, ROS hyperproduction, and increased colocalization of mitochondria with lysosomes. Bongkrekic acid (25 µM) attenuated palmitate-induced lipotoxicity and all the signs of mitochondrial damage, including increased spontaneous formation of the MPT pore. In contrast, carboxyatractyloside (10 μM) stimulated cell death and failed to prevent the progression of mitochondrial dysfunction under hyperlipidemic stress conditions. Silencing of gene expression of the predominate isoform ANT2, similar to the action of carboxyatractyloside, led to increased ROS generation and cell death under conditions of palmitate-induced lipotoxicity in a stably transfected HEK293T cell line. Altogether, these results suggest that targeted manipulation of the permeability transition pore through inhibition of ANT may represent an alternative approach to alleviate mitochondrial dysfunction and cell death in cell culture models of fatty acid overload.
Recent research indicates that some types of mental illnesses (schizophrenia, autism, depressive disorders) may be associated with impaired functioning of a number of genes, including those involved in brain morphogenesis. To assess the possible contribution of brain morphogenesis genes in the formation of predisposition to depressive disorders in Russian population, we performed whole-exome sequencing of genomic DNA of such patients. We identified 166 missense genomic variants in 66 genes (out of 140 studied) involved in the formation of brain tissue. The prevalence of some of them was estimated by allele-specific PCR. For the first time, a significantly higher frequency of occurrence of genomic variants rs17445840‑T (CDH2 gene), rs12923655‑C (CDH3 gene), rs1227051‑G/A (CDH23 gene), and rs12500437‑G/T (DCHS2 gene) was shown in a group of patients suffering from endogenous depressive disorder, and an association of some of the identified genomic variants with gender was established. The data obtained confirm the previously stated assumption that genes of brain tissue morphogenesis may be associated with a predisposition to the development of mental and cognitive disorders. The functional significance of the identified genetic variants remains to be established. The identification of pathogenic genomic variants with the confirmation of their functional significance allows better understanding of the pathogenesis of mental disorders and opens prospects for the development of approaches to objective diagnosis of such diseases, their early prevention, and pathogenetic therapy.
Ischemic and hemorrhagic strokes, traumatic brain injury, bacterial and viral encephalitis, toxic and metabolic encephalopathies are very different pathologies. But, they have much more in common than it might seem at first glance. In this review, the authors propose to consider these brain pathologies from the point of view of the unity of their pathogenetic mechanisms and approaches to therapy. Particular attention is paid to promising therapeutic approaches, such as therapy using cells and their secretion products: an analysis of the accumulated experimental data, the advantages and limitations of these approaches in the treatment of brain damage was carried out. The review may be of interest both to specialists in the field of neurology, neurosurgery and neurorehabilitation, and to readers who want to learn more about the progress of regenerative biomedicine in the treatment of brain pathologies.
Intracerebral hemorrhage is an unmet medical need that often leads to the disability and death of a patient. The lack of effective treatments for intracerebral hemorrhage makes it necessary to look for them. Previously, in our proof-of-concept study (Karagyaur M et al. Pharmaceutics, 2021), we have shown that the secretome of multipotent mesenchymal stromal cells (MSC) provides neuroprotection of the brain in a model of intracerebral hemorrhage in rats. Here, we have conducted a systematic study of the therapeutic potential of the MSC secretome in the model of hemorrhagic stroke and provided answers to the questions that need to be addressed in order to translate the secretome-based drug into clinical practice: routes and multiplicity of administration, optimal dose and door-to-treatment time. We have found that MSC secretome reveals prominent neuroprotective activity when administered intranasally or intravenously within 1–3 h after hemorrhage modeling, even in aged rats, and its multiple injections (even within 48 h) are able to reduce the delayed negative effects of hemorrhagic stroke. To our knowledge, this study provides the first systematic investigation of the therapeutic activity of a biomedical MSC-based cell-free drug in intracerebral hemorrhage and is an integral part of its preclinical studies.
Non-coding RNA (ncRNAs) genes have attracted increasing attention in recent years due to their widespread involvement in physiological and pathological processes and regulatory networks. The study of the function and molecular partners of ncRNAs opens up opportunities for the early diagnosis and treatment of previously incurable diseases. However, the classical "loss-of-function" approach in ncRNA function analysis is challenged due to some specific issues. Here, we have studied the potency of two CRISPR/Cas9 variants, wild-type (SpCas9wt) and nickase (SpCas9D10A) programmable nucleases, for the editing of extended DNA sequences in human mesenchymal stromal cells (MSCs). Editing the genes of fibrosis-related hsa-miR-21-5p and hsa-miR-29c-3p, we have shown that a pair of SpCas9D10A molecules can effectively disrupt miRNA genes within the genomes of MSCs. This leads not only to a decrease in the level of knockout miRNA in MSCs and MSC-produced extracellular vesicles, but also to a change in cell physiology and the antifibrotic properties of the cell secretome. These changes correlate well with previously published data for the knockdown of certain miRNAs. The proposed approach can be used to knock out ncRNA genes within the genomes of MSCs or similar cell types in order to study their function in biological processes.
Introduction The prevalence of depression averages approximately 6 % of the total population. The heritability of depression ranges from 28 % to 44 %. Genetic predisposition may be due to polymorphisms of genes involved in the processes of functioning and morphogenesis of the brain: the balance of monoamines, the action of navigational molecules and their receptors.Purpose of the study To determine the role of genes that regulate the processes of nerve cell migration and directed growth of nerve fibers of navigation receptors (PLAUR and CDH13) or their ligands (PLAU, PLAT, ADIPOQ) in the development of endogenous depression and schizophrenia in the Russian population.Materials and methods At the first stage of the study, the scientific literature was searched in the MEDLINE database. The primary prevalence of genomic variants will be established using whole genome sequencing of 20 patients with severe forms of schizophrenia and endogenous depression. Further, at least 100 patients in each group and 100 healthy donors will take part in the study.Results and discussion The urokinase receptor (uPAR) is involved in neurogenesis by regulating the trajectory of axonal growth. The level of suPAR in blood plasma can act as a biomarker of mild inflammation underlying the etiology of depression. The level of suPAR in plasma can be considered a predictor of the effectiveness of combination therapy with antidepressants and anti-inflammatory drugs. Molecules of the cadherin superfamily are involved in the development of the nervous system, the transmission of intercellular signals, and the regulation of neuronal plasticity. Polymorphisms of the CDH7, CDH9, CDH13, CDH17 genes demonstrate a correlation with the presence of depression. Adiponectin is a hormone secreted by adipose tissue. One of the adiponectin receptors, AdipoR2, stimulates neuronal plasticity and inhibits inflammation and oxidative stress. Plasma concentrations of adiponectin are reduced in depressed patients.Conclusion The results accumulated by researchers testify in favor of the important role of uPAR and T-cadherin in the processes of brain development, and most importantly, in the pathogenesis of the development of endogenous depressions.
The growing interest in potassium channels as pharmacological targets has stimulated the development of their fluorescent ligands (including genetically encoded peptide toxins fused with fluorescent proteins) for analytical and imaging applications. We report on the properties of agitoxin 2 C-terminally fused with enhanced GFP (AgTx2-GFP) as one of the most active genetically encoded fluorescent ligands of potassium voltage-gated Kv1.x (x = 1, 3, 6) channels. AgTx2-GFP possesses subnanomolar affinities for hybrid KcsA-Kv1.x (x = 3, 6) channels and a low nanomolar affinity to KcsA-Kv1.1 with moderate dependence on pH in the 7.0–8.0 range. Electrophysiological studies on oocytes showed a pore-blocking activity of AgTx2-GFP at low nanomolar concentrations for Kv1.x (x = 1, 3, 6) channels and at micromolar concentrations for Kv1.2. AgTx2-GFP bound to Kv1.3 at the membranes of mammalian cells with a dissociation constant of 3.4 ± 0.8 nM, providing fluorescent imaging of the channel membranous distribution, and this binding depended weakly on the channel state (open or closed). AgTx2-GFP can be used in combination with hybrid KcsA-Kv1.x (x = 1, 3, 6) channels on the membranes of E. coli spheroplasts or with Kv1.3 channels on the membranes of mammalian cells for the search and study of nonlabeled peptide pore blockers, including measurement of their affinity.
Extracellular vesicles are macromolecular complexes produced by virtually all types of eukaryotic and prokaryotic cells. According to modern concepts, they allow cells to exchange information, regulate each other’s activity and coordinate their actions during the complex processes of development, maintaining homeostasis, tissue regeneration, etc. Extracellular vesicles have a number of unique properties: the ability to accumulate certain types of proteins and nucleic acids, protect them from degradation and ensure their delivery to target cells, which can be used to create biomimetic approaches to the therapy of a wide range of diseases. The composition of vesicles, the preference for docking with a particular cell type, and ultimately their therapeutic potential are very flexible parameters and are highly dependent on the type and properties of the producer cell culture, as well as cultivation conditions. This review gives an idea of the state and prospects of the therapeutic strategies implied the application of extracellular vesicles for neuroprotection and stimulation of brain tissue regeneration after injury, and also considers existing clinical studies which use extracellular vesicles in the field of neurology and neurosurgery. Particular attention in the review is given to new promising approaches to increasing the production of extracellular vesicles, manipulating their contents, and increasing the efficiency of targeted docking in order to increase their therapeutic activity and specificity.
Prolonged hyperglycemia related to diabetes and its complications leads to multiple cellular disorders, the central one being the dysfunction of mitochondria. Voltage-dependent anion channels (VDAC) of the outer mitochondrial membrane control the metabolic, ionic, and energy cross-talk between mitochondria and the rest of the cell and serve as the master regulators of mitochondrial functions. Here, we have investigated the effect of pharmacological suppression of VDAC1 by the newly developed inhibitor of its oligomerization, VBIT-4, in the primary culture of mouse lung endotheliocytes and downregulated expression of VDAC1 in human skin fibroblasts on the progression of mitochondrial dysfunction upon hyperglycemic stress. The cells were grown in high-glucose media (30 mM) for 36 h. In response to hyperglycemia, the mRNA level of VDAC1 increased in endotheliocytes and decreased in human skin fibroblasts. Hyperglycemia induced overproduction of mitochondrial ROS, an increase in the susceptibility of the organelles to mitochondrial permeability transition (MPT) pore opening and a drop in mitochondrial membrane potential, which was accompanied by a decrease in cell viability in both cultures. Treatment of endotheliocytes with 5 µM VBIT-4 abolished the hyperglycemia-induced increase in susceptibility to spontaneous opening of the MPT pore and ROS generation in mitochondria. Silencing of VDAC1 expression in human skin fibroblasts exposed to high glucose led to a less pronounced manifestation of all the signs of damage to mitochondria. Our data identify a mitochondria-related response to pharmacological and genetic suppression of VDAC activity in vascular cells in hyperglycemia and suggest the potential therapeutic value of targeting these channels for the treatment of diabetic vasculopathies.
Relevance. The use of gene therapy drugs for the treatment of genetic diseases and stimulation of regeneration processes is lengthy and involves repeated injections, which may lead to increased dissemination of gene therapy constructs from the injection site and undesirable ectopic expression of growth factors encoded in them. Existing approaches to study the pharmacokinetics of a drug to assess the dissemination of a gene therapy drug from the site of administration are not applicable. Objective: to evaluate the suitability of the real-time PCR method for studying the biodistribution of a promising gene therapy drug in mice during a course of use. Methods. Male F1 CBA×C57/Black mice after nerve injury were injected with the test plasmid into the denervated tibial muscle after nerve injury, as well as after 4, 9 and 13 days at a dosage of 60 and 120 μg/mouse. After 7, 14, and 28 days, organ and tissue samples were removed, total DNA was isolated, and plasmid DNA content was assessed by real-time PCR. Results. We have shown that the studied genetic construct is able to disseminate from the injection site. We have found that the peak of dissemination for this construct in the organs and tissues of the mouse is reached 14–28 days after the end of the course application, while ectopic expression of growth factors is not observed in them. Conclusion. The proposed method is specific, highly sensitive, and linear over a wide range of concentrations. Thus, it can be recommended for studying the biodistribution of potential gene therapy drugs in the body of experimental animals as part of a preclinical studies complex.