RNA interference (RNAi)-based therapeutics hold the potential for dominant genetic disorders, enabling sequence-specific inhibition of pathogenic gene products. We aimed to direct RNAi for the selective suppression of the heterozygous GNAO1 c.607 G > A variant causing GNAO1 encephalopathy. By screening short interfering RNA (siRNA), we showed that GNAO1 c.607G>A is a druggable target for RNAi. The si1488 candidate achieved at least twofold allelic discrimination and downregulated mutant protein to 35%. We created vectorized RNAi by incorporating the si1488 sequence into the short hairpin RNA (shRNA) in the adeno-associated virus (AAV) vector. The shRNA stem and loop were modified to improve the transcription, processing, and guide strand selection. All tested shRNA constructs demonstrated selectivity toward mutant GNAO1, while tweaking hairpin structure only marginally affected the silencing efficiency. The selectivity of shRNA-mediated silencing was confirmed in the context of AAV vector transduction. To conclude, RNAi effectors ranging from siRNA to AAV-RNAi achieve suppression of the pathogenic GNAO1 c.607G>A and discriminate alleles by the single-nucleotide substitution. For gene therapy development, it is crucial to demonstrate the benefit of these RNAi effectors in patient-specific neurons and animal models of the GNAO1 encephalopathy.

The development of personalized medicine for genetic diseases requires preclinical testing in the appropriate animal models. GNAO1 encephalopathy is a severe neurodevelopmental disorder caused by heterozygous de novo mutations in the GNAO1 gene. GNAO1 c.607 G>A is one of the most common pathogenic variants, and the mutant protein Gαo-G203R likely adversely affects neuronal signaling. As an innovative approach, sequence-specific RNA-based therapeutics such as antisense oligonucleotides or effectors of RNA interference are potentially applicable for selective suppression of the mutant GNAO1 transcript. While in vitro validation can be performed in patient-derived cells, a humanized mouse model to rule out the safety of RNA therapeutics is currently lacking. In the present work, we employed CRISPR/Cas9 technology to introduce a single-base substitution into exon 6 of the Gnao1 to replace the murine Gly203-coding triplet (GGG) with the codon used in the human gene (GGA). We verified that genome-editing did not interfere with the Gnao1 mRNA or Gαo protein synthesis and did not alter localization of the protein in the brain structures. The analysis of blastocysts revealed the off-target activity of the CRISPR/Cas9 complexes; however, no modifications of the predicted off-target sites were detected in the founder mouse. Histological staining confirmed the absence of abnormal changes in the brain of genome-edited mice. The created mouse model with the “humanized” fragment of the endogenous Gnao1 is suitable to rule out unintended targeting of the wild-type allele by RNA therapeutics directed at lowering GNAO1 c.607 G>A transcripts.

Duchenne muscular dystrophy (DMD) is a severe hereditary disease caused by a deficiency in the dystrophin protein. The most frequent types of disease-causing mutations in the DMD gene are frameshift deletions of one or more exons. Precision genome editing systems such as CRISPR-Cas9 have shown potential to restore open reading frames in numerous animal studies. Here, we applied an AAV-CRISPR double-cut strategy to correct a mutation in the DMD mouse model with exon 8-34 deletion, encompassing the N-terminal actin-binding domain. We report successful excision of the 100-kb genomic sequence, which includes exons 6 and 7, and partial improvement in cardiorespiratory function. While corrected mRNA was abundant in muscle tissues, only a low level of truncated dystrophin was produced, possibly because of protein instability. Furthermore, CRISPR-Cas9-mediated genome editing upregulated the Dp71f dystrophin isoform on the sarcolemma. Given the previously reported Dp71-associated muscle pathology, our results question the applicability of genome editing strategies for some DMD patients with N-terminal mutations. The safety and efficacy of CRISPR-Cas9 constructs require rigorous investigation in patient-specific animal models.

Mutations that prevent the production of proteins in the DMD gene cause Duchenne muscular dystrophy. Most frequently, these are deletions leading to reading-frame shift. The "reading-frame rule" states that deletions that preserve ORF result in a milder Becker muscular dystrophy. By removing several exons, new genome editing tools enable reading-frame restoration in DMD with the production of BMD-like dystrophins. However, not every truncated dystrophin with a significant internal loss functions properly. To determine the effectiveness of potential genome editing, each variant should be carefully studied in vitro or in vivo. In this study, we focused on the deletion of exons 8-50 as a potential reading-frame restoration option. Using the CRISPR-Cas9 tool, we created the novel mouse model DMDdel8-50, which has an in-frame deletion in the DMD gene. We compared DMDdel8-50 mice to C57Bl6/CBA background control mice and previously generated DMDdel8-34 KO mice. We discovered that the shortened protein was expressed and correctly localized on the sarcolemma. The truncated protein, on the other hand, was unable to function like a full-length dystrophin and prevent disease progression. On the basis of protein expression, histological examination, and physical assessment of the mice, we concluded that the deletion of exons 8-50 is an exception to the reading-frame rule.

Disease-causing genes have been identified for many severe muscular and neurological genetic disorders. Advances in the gene therapy field offer promising solutions for drug development to treat these life-threatening conditions. Depending on how the mutation affects the function of the gene product, different gene therapy approaches may be beneficial. Gene replacement therapy is appropriate for diseases caused by mutations that result in the deficiency of the functional protein. Gene suppression strategy is suggested for disorders caused by the toxic product of the mutant gene. Splicing modulators, genome editing, and base editing techniques can be applied to disorders with different types of underlying mutations. Testing potential drugs in animal models of human diseases is an indispensable step of development. Given the specific gene therapy approach, appropriate animal models can be generated using a variety of technologies ranging from transgenesis to precise genome editing. In this review, we discuss technologies used to generate small and large animal models of the most common muscular and neurological genetic disorders. We specifically focus on animal models that were used to test gene therapies based on adeno-associated vectors and antisense nucleotides.

Mutations in the Dmd gene encoding the membrane protein dystrophin are associated with the development of severe X-linked muscle diseases Duchenne and Becker myodystrophy. At the same time, along with the classic symptoms of striated muscles, dystrophin mutations can lead to a decrease in cognitive functions and behavioral abnormalities. Objective: conducting a pilot analysis of behavioral and cognitive characteristics in mice with a genetic defect that reproduces the phenotype of Duchenne myodystrophy. Materials and methods. To assess the features of motor functions and behavior, DmdDel8-34(n=13) and control animals of the wild type (n=12) were subjected to research in the tests "Load retention", "Rotarod", "Elevated plus maze" and "Object recognition". Results. It was found that mice carrying the DmdDel8-34 mutation are characterized by a decrease in motor functions, show signs of anxiety, and also show low exploratory activity. The detected features of the cognitive and emotional status are consistent with clinical observations indicating an increased risk of developing autism spectrum disorders and obsessive-compulsive disorder in patients with Dmd gene mutations. Thus, it was proved that from the 8th week of life, mice of the DmdDel8-34 line show a decrease in performance in the Rotarod and Load Retention tests. Behavioral testing in the Elevated Plus Maze test revealed a decrease in time reaching a statistically significant difference compared to the wild-type control at week 12, and when assessing cognitive functions in the Object Recognition test, it was shown that DmdDel8-34mice show an increase in the discrimination index value, which is a sign of increased efficiency of hippocampal memory. Conclusion. The study made it possible to identify some behavioral anomalies in genetically modified mice carrying a large deletion of exons 8-34 of the Dmd gene encoding dystrophin.

High expectations have been set on gene therapy with an AAV-delivered shortened version of dystrophin (µDys) for Duchenne muscular dystrophy (DMD), with several drug candidates currently undergoing clinical trials. Safety concerns with this therapeutic approach include the immune response to introduced dystrophin antigens observed in some DMD patients. Recent reports highlighted microutrophin (µUtrn) as a less immunogenic functional dystrophin substitute for gene therapy. In the current study, we created a human codon-optimized µUtrn which was subjected to side-by-side characterization with previously reported mouse and human µUtrn sequences after rAAV9 intramuscular injections in mdx mice. Long-term studies with systemic delivery of rAAV9-µUtrn demonstrated robust transgene expression in muscles, with localization to the sarcolemma, functional improvement of muscle performance, decreased creatine kinase levels, and lower immunogenicity as compared to µDys. An extensive toxicity study in wild-type rats did not reveal adverse changes associated with high-dose rAAV9 administration and human codon-optimized µUtrn overexpression. Furthermore, we verified that muscle-specific promoters MHCK7 and SPc5-12 drive a sufficient level of rAAV9-µUtrn expression to ameliorate the dystrophic phenotype in mdx mice. Our results provide ground for taking human codon-optimized µUtrn combined with muscle-specific promoters into clinical development as safe and efficient gene therapy for DMD.

На основе инверсии синтетических данных, полученных путем двумерного и трехмерного моделирования, проведено сравнение разрешающей способности нескольких установок электротомографии, применяемых при решении рудных задач до глубин 400-500 м. Установки AMN + MNB и ABMN, используемые в протоколах многоканальных станций, сравнивались с нестандартными установками электротомографии, позволяющими проводить измерения с одноканальной или малоканальной аппаратурой. Использовались количественные оценки, показывающие суммарное отклонение всех границ аномалиеобразующих объектов и разницу удельного электрического сопротивления в исходной и инверсионной моделях. Широкий модельный ряд, использование разных вмещающих разрезов и глубин залегания целевых тел позволили получить обширную статистику, отражающую преимущества и недостатки той или иной установки ЭТ. Based on the inversion of synthetic data obtained by two-dimensional and three-dimensional modeling, a comparison was made of several electrotomography arrays used in solving ore problems to depths of 400-500 m. The AMN+MNB and ABMN arrays used in the protocols of multichannel stations were compared with non-standard electrotomography arrays used with single-channel or low-channel equipment. Quantitative estimates were used showing the total deviation of all boundaries of anomalous objects and the difference in electrical resistivity in the initial and inversion models. A wide range of models, different host medium and depths of cover of anomalous bodies made it possible to obtain extensive statistics reflecting the advantages and disadvantages of electrotomography arrays.

A new approach to the synthesis of isomeric 19-hydroxypregn-4-en-20-one (1) and 19-hydroxy-5β-pregn-3-en-20-one (2), the selective ligands of membrane progesterone receptors, in a ratio of 1.5:1 is presented. The effect of these steroids on the gene expression of several cytokines (TNFα, IL-1β, IL-6, and TGFβ) in K562 cells was studied. Progesterone and compound 1 acted unidirectionally, significantly decreasing the TGFβ mRNA levels in these cells. The highest activity was exhibited by compound 2 which regulated the expression of the three studied genes, increasing the level of TNFα mRNA and IL-1β mRNA and decreasing the level of TGFβ mRNA. The immunomodulatory effect of the synthesized selective ligands of membrane progesterone receptors found in K562 cells is comparable (for 1) or even surpasses (for 2) the effect of a natural hormone.

Duchenne muscular dystrophy is a complex and severe orphan disease. It develops when the organism lacks the expression of dystrophin - a large structural protein. Dystrophin is transcribed from the largest gene in the human genome. At the moment, there is no cure available. Dozens of groups all over the world search for cure. Animal models are an important component of both the fundamental research and therapy development. Many animal models reproducing the features of disease were created and actively used since the late 80’s until present. The species diversity spans from invertebrates to primates and the genetic diversity of these models spans from single mutations to full gene deletions. The models are often non-interchangeable; while one model may be used for particular drug design it may be useless for another. Here we describe existing models, discuss their advantages and disadvantages and potential applications for research and therapy development.

Summary The goal is to assess the possibilities of electrotomography for the study of heavy oil deposits. The main object of study is the largest tar sand deposit - Alberta (western province of Canada).There are some problems with the production of such oil: 1) Reservoir heterogeneity associated with interlayers of clays and shales. This is a significant obstacle to vertical vapor migration; 2) watercut zones. Based on this, the following tasks arise before the electrotomography: 1) Select tar sand layers and estimate their thickness; 2) Select the conductive horizons (clay, shale, water) that may be present in the oil-bearing strata. The assessment of the capabilities of electrotomography was carried out using simulation with subsequent inversion. Models were created to match the geological structure of the region (Alberta, Canada). Comparing the results of solving the inverse problem (inversion) with the starting model gives this estimate. In the process of modeling, a pole-dipole + dipole-dipole electrotomography unit was used.

Electrical geophysical prospecting methods are widely used at different stages of geological exploration. In the last two decades, new computer technologies and satellite navigation systems were successfully introduced in the geophysical industry. As a result, exploration technologies have improved, and new geophysical methods have been developed, such as electrical resistivity tomography (ERT) and spectral induced polarization (SIP) methods. An important role in ore geophysics is played by magnetotelluric (MT) methods. In this article, we focus on the issues of methodology and interpretation of electrical prospecting data for solving ore exploration problems. Special attention is paid to the induced polarization (IP) method that is most widely used in mineral exploration and mining industry as one of the most important and most dynamically developing techniques of ore geophysics. In addition, the issues of correct choices of survey scales and the use of automatic 2D and 3D inversion programs are considered.

Summary The works by the method of electrotomography (ET) were carried out on the right bank of the riverwtkm Volga. The primary goal of the work is to study the geological structure of the upper part of the section for the selection of sites for the installation of the road bridge supports. On the slope, measurements were made along 9 (10) profiles oriented across the river bed. Several profiles were made on the slope. A Syscal Pro Switch 72 multichannel station manufactured by Iris Instruments (France) was used for measurements. Interpretation of ET data was performed in 2D inversion modes (ZONDRES2D program, author – A.E. Kaminskiy, [ 2 ]) and 3D inversion (ZONDRES3D program by the same author). One of the methodological tasks was to compare the 2D and 3D results for the depth and detail of the final geoelectric model. In addition, in the course of interpretation, we estimated the equivalence of solving the inverse 2D problem, depending on the choice of the starting model.

AAV-delivered microdystrophin genes hold great promise for Duchenne muscular dystrophy (DMD) treatment. It is anticipated that the optimization of engineered dystrophin genes will be required to increase the efficacy and reduce the immunogenicity of transgenic proteins. An in vitro system is required for the efficacy testing of genetically engineered dystrophin genes. We report here on the proof of concept for an in vitro assay based on the assessment of sarcolemma damage after repetitively applied electrical stimuli. The primary cell culture of myoblasts was established from wild-type C57BL/10ScSnJ and dystrophin-deficient mdx mice. The preparation parameters and the differentiation of contractile myotubes were optimized. DAPI and TO-PRO-3 dyes were used to assess myotubular membrane permeability in response to electrical pulse stimulation (EPS). Myotubes derived from mdx mice exhibited a greater increase in membrane damage, as assessed by TO-PRO-3-measured permeability after EPS, than was exhibited by the healthy control myotubes. AAV-DJ particles carrying the microdystrophin gene were used to transduce mdx-derived differentiated myotubes. Microdystrophin delivery ameliorated the disease phenotype and reduced the EPS-induced membrane damage to a level comparable to that of the healthy controls. Thus, the in vitro system was shown to be capable of supporting studies on DMD gene therapy.

Exon skipping is a promising strategy for Duchenne muscular dystrophy (DMD) disease-modifying therapy. To make this approach safe, ensuring that excluding one or more exons will restore the reading frame and that the resulting protein will retain critical functions of the full-length dystrophin protein is necessary. However, in vivo testing of the consequences of skipping exons that encode the N-terminal actin-binding domain (ABD) has been confounded by the absence of a relevant animal model. We created a mouse model of the disease recapitulating a novel human mutation, a large de novo deletion of exons 8-34 of the DMD gene, found in a Russian DMD patient. This mutation was achieved by deleting exons 8-34 of the X-linked mouse D md gene using CRISPR/Cas9 genome editing, which led to a reading frame shift and the absence of functional dystrophin production. Male mice carrying this deletion display several important signs of muscular dystrophy, including a gradual age-dependent decrease in muscle strength, increased creatine kinase, muscle fibrosis and central nucleation. The degrees of these changes are comparable to those observed in mdx mice, a standard laboratory model of DMD. This new model of DMD will be useful for validating therapies based on skipping exons that encode the N-terminal ABD and for improving our understanding of the role of the N-terminal domain and central rod domain in the biological function of dystrophin. Simultaneous skipping of exons 6 and 7 should restore the gene reading frame and lead to the production of a protein that might retain functionality despite the partial deletion of the ABD.

Progesterone (P4) and its analogues regulate various reproductive processes, such as ovulation, implantation, pregnancy maintenance and delivery. In these processes, an important role is played by the immune cells recruited to the female reproductive organs and tissues, where they are exposed to the action of P4. Progestins regulate cellular processes, acting through nuclear steroid receptors (nSRs), membrane P4 receptors (mPRs), and through the sensors. It remains unclear, what type of receptors is used by P4 and its derivatives to exert their effect on the immune cells and how similar their effects are in different types of these cells. We have previously synthesized new progesterone derivatives, among which two selective mPRs ligands, not interacting with nSRs were identified. The objective of this study was to examine the effects of P4 and new selective mPRs ligands on the expression of pro- and anti-inflammatory cytokines in activated human peripheral blood mononuclear cells (PBMCs), THP-1 monocyte cells, and Jurkat T cells. It was demonstrated that the action of P4 and selective ligands was unidirectional, but in different types of the immune cells, their effects were different, and sometimes even opposite. In PBMCs, exposure to these steroids resulted in the increase of mRNA and secreted protein levels of IL-1β, TNFα, and IL-6 cytokines, as well as in the increase of INFγ mRNA level, decrease of IL-2 mRNA level, increase of TGFβ mRNA level, and decrease of IL-4 mRNA and IL-10 secreted protein levels. In monocytes, similarly to PBMCs, expression of IL-1β and TNFα mRNA was increased, but expression of IL-10 was also increased, and the TGFβ expression statistically significantly remained the same. In Jurkat T cells, expression of IL-2 and TNFα mRNA decreased, while expression of IL-10 increased, and expression of TGFβ did not change. Thus, progestins act on the immune cells through mPRs and have both pro- and anti-inflammatory effects, depending on the phenotypes of these cells. The data obtained are important for understanding the complexity of the immune system regulation by progestins, which depends on the type of the immune cells and individual characteristics of the immune system.

We studied changes in the expression of mRNA for mucins and claudins in the medial part of the colon in male C57Bl/6 mice on the model of acute and chronic colitis induced by substitution of drinking water with 1% solution of dextran sodium sulphate for 5 days. In acute colitis, the expression of the main structural component of glycocalyx, mucin Muc3, decreased and expression of pore-forming claudin Cldn2 increased, which reflected enhanced permeability of tight junctions. In the chronic colitis group, in comparison with the normal group, we observed an increase in expression of mRNA of main structural mucus component Muc2, enhanced of expression of Muc1 associated with carcinogenesis, and reduced expression of Muc13, which led to a more severe course of colitis; the expression of pore-forming claudin Cldn2 was elevated. These findings indicate that the imbalance in the expression of mucins and claudins plays an important role in the mechanisms of development of acute and chronic colitis.

Identification of progesterone selective agonists and antagonists that act through one of the nuclear progesterone receptor isoforms is of particular importance for the development of tissue-specific drugs in gynecology and anticancer therapy. Fourteen pregna-D′ 6 - and pregna-D′ 3 -pentarane progesterone derivatives with 16α,17α-cycloalkane groups and two progesterone 3-deoxyderivatives were examined for their ability to regulate transcriptional activity of human nuclear progesterone receptor isoform B (nPR-B) expressed in Saccharomyces cerevisiae yeast. Transcriptional activity of nPR-B was measured from the expression of the β-galactosidase reporter gene with a hormone-responsible element in the promoter. Among the compounds tested, two were full progesterone agonists, four were partial agonists, one compound possessed both agonistic and antagonistic activity, one compound displayed only partial antagonistic activity, and eight compounds did not show any activity. Modifications of the pentarane structure, precisely, introduction of an additional double bound in the A or B rings and/or modification at the 6th position of progesterone, lead to a switch from the complete agonistic activity to partial agonistic or mixed activities. These modifications enable progestins to act as selective modulators of progesterone receptor. Steroids with reduced A-ring and 3-ketogroups lose their ability to regulate PR-B activity. Both 3-deoxycompounds, being selective ligands of progesterone membrane receptors, do not affect PR-B activity.

Актуальность. Селектированная на проявление судорог в ответ на сильный звук (аудиогенную эпилепсию, АЭ) линия крыс Крушинского-Молодкиной (КМ) - модель судорожных состояний человека, c быстрым развитием судорожного припадка в ответ на включение звука (100-120 дБ). Однако у крыс с АЭ изменений уровня кортикостерона (КС) в крови в связи с судорогами не определяли, хотя анализ связи АЭ и стресс-реакции - важная практическая задача. Методы. Уровень КС в образцах сыворотки крови определяли с помощью набора у крыс линии КМ, а также у крыс линии «0», селектированных из гибридной популяции КМ х Вистар на отсутствие АЭ, и у крыс популяции Вистар. Результаты. У всех крыс КМ был зарегистрирован аудиогенный припадок, тогда как у крыс линии «0» и Вистар судорог не было. Через 30 мин после действия звука (и судорог) у крыс КМ повышеается уровень КС, тогда как сразу после судорог (через 1-3 мин) данная реакция не обнаруживается. У крыс линии «0» обнаружен достоверно более высокий фоновый уровень КС, по сравнению с КМ и Вистар. Уровень КС у них, как и у крыс Вистар, после действия звука не изменялся. Заключение. Подъем уровня КС в крови после действия звука наблюдали только у крыс КМ через 30 мин после припадка АЭ. Крысы линии «0», у которых нет судорог в ответ на звук, обнаружили более высокий, чем у КМ и Вистар уровень КС в фоне. Aims. The Krushinsky-Molodkina (KM) rat strain, which was selected for a seizure response to a sound (audiogenic epilepsy, AE), is known as a model of human seizure states. Although the association of blood CS with stress reaction is an important practical issue, blood levels of corticosterone (CS) have never been analyzed in rats with AE in relation with seizures. Methods. Serum concentration of CS was measured using IBL International Corticosterone ELISA kits in KM rats, rats of the «0» strain, which was selected (based on F2 KM х Wistar hybrids) for the lack of seizures in response to a sound, and Wistar rats. Results. All KM rats developed AE seizures in response to a sound while no seizures were observed in rats of the «0» strain and Wistar rats. The increase in blood CS was observed only in KM rats at 30 min after AE seizure. At background, the level of CS was significantly higher in rats of the «0» strain, which did not develop seizures in response to a sound, than in KM and Wistar rats. CS levels remained unchanged in both «0» and Wistar rats after the sound exposure. Conclusions. The increase in blood CS occurred in KM rats at 30 min after the seizure episode. At background, the CS level was higher in rats of the «0» strain, which did not respond with seizures to a sound, than in Wistar and KM rats. Therefore, the blood level of CS depends in a complicated way on both AE and the selection history of the «0» rat strain.