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Preeclampsia is a multisystem pregnancy disorder that occurs after 20 weeks of gestation, leading to e.g. preterm labor. It is characterized by hypertension, proteinuria, edema, and multiple organ dysfunction. Up to 8% of pregnancies are complicated by preeclampsia, which is one of the most serious causes of maternal and perinatal mortality [1]. For research of pregnancy disorders and development of therapy for it, a mouse model can be used due of the fact that pregnancy development in mice, especially at early stages, is somewhat similar to human and is well-studied, in particular, in terms of molecular biology [2]. One of the possible options for creating mouse models of preeclampsia is considered to be a mutation in the COMT gene encoding сatechol-O-methyltransferase [3]. This enzyme plays an important role in the catecholamines conversion and it also catalyzes the O-methylation of hydroxyestradiol producing methoxyestradiol. COMT gene knockout results in a phenotype similar to preeclampsia with elevated blood pressure and proteinuria [3]. The previous model was obtained through classic transgenesis methods with Neomycin cassette insertion in the COMT locus potentially influencing the results of the experiments. The development of the genome editing systems and its active utilization at Saint Petersburg State University made it possible to obtain a COMT-KO mouse line using CRISPR/Cas9 technology which had not been done in Russia before. This model will allow to effectively study the development of preeclampsia and ways to prevent and treat it. This work was supported by a Saint Petersburg State University grant for the development of scientific research (ID 92561695).

In the modern world, due to the overconsumption of sugar-containing products, the problem of obesity is relevant. Among the many sweeteners that minimize sugar intake, a group of sweet-tasting proteins is up-and-coming. Brazzein is the smallest of the sweet proteins (54 aa, 6473 Da), and it is also safe for obese and diabetic people since it does not affect blood sugar and insulin levels. Brazzein has high thermal stability over a wide pH range: from 2 to 8 [1]. To increase the level of sweetness of brazzein, mutant variants of this protein were created through site-directed mutagenesis, the sweetest of which is triple mutant H31R/E36D/E41A, which is 22,500 times sweeter than sucrose [2]. Since the content of brazzein in the fruits of the natural source (Pentadiplandra brazzeana) is extremely low (0.2%), various methods have been developed to obtain brazzein using heterologous expression systems, which used as producers: bacteria (Escherichia coli, Lactococcus lactis), yeast (Pichia pastoris, Kluyveromyces lactis, Saccharomyces cerevisiae), plants (Zea mays, Oryza sativa, Lactuca sativa, Nicotiana tabacum) and animals (Mus musculus) [35]. Despite the short peptide sequence, the industrial production of recombinant protein faced several problems, including low protein yield (e.g in mouse milk it was detectable on western blot analysis only) and loss of sweetness. Аn extremely relevant and promising way to obtain recombinant brazzein is the optimization of extracellular expression in bakers yeasts with the GRAS (Generally recognized as safe) status, since the safety of these microorganisms for human health can potentially significantly reduce the number of brazzein purification steps and thereby reduce its cost to consumers.

The identification and characterization of ligand-receptor binding sites are important for drug development. Trace amine-associated receptors (TAARs, members of the class A GPCR family) can interact with different biogenic amines and their metabolites, but the structural basis for their recognition by the TAARs is not well understood. In this work, we have revealed for the first time a group of conserved motifs (fingerprints) characterizing TAARs and studied the docking of aromatic (β-phenylethylamine, tyramine) and aliphatic (putrescine and cadaverine) ligands, including gamma-aminobutyric acid, with human TAAR1 and TAAR6 receptors. We have identified orthosteric binding sites for TAAR1 (Asp68, Asp102, Asp284) and TAAR6 (Asp78, Asp112, Asp202). By analyzing the binding results of 7500 structures, we determined that putrescine and cadaverine bind to TAAR1 at one site, Asp68 + Asp102, and to TAAR6 at two sites, Asp78 + Asp112 and Asp112 + Asp202. Tyramine binds to TAAR6 at the same two sites as putrescine and cadaverine and does not bind to TAAR1 at the selected Asp residues. β-Phenylethylamine and gamma-aminobutyric acid do not bind to the TAAR1 and TAAR6 receptors at the selected Asp residues. The search for ligands targeting allosteric and orthosteric sites of TAARs has excellent pharmaceutical potential.

Cell repair machinery is responsible for protecting the genome from endogenous and exogenous effects that induce DNA damage. Mutations that occur in somatic cells lead to dysfunction in certain tissues or organs, while a violation of genomic integrity during the embryonic period often leads to death. A mammalian embryo’s ability to respond to damaged DNA and repair it, as well as its sensitivity to specific lesions, is still not well understood. In this review, we combine disparate data on repair processes in the early stages of preimplantation development in mammalian embryos.

The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) - RNA-guided Cas9 endonuclease system has provided a fast and efficient method for precise genome editing in diverse mammalian species, including humans. The CRISPR/Cas9 technology allows generation of modifications into site-specific locations of the selected genes in one major step by carrying deletions, insertions or DNA donor-directed precise sequence modifications. Cas9 forms a nucleoprotein complex with a sequence-specific guide RNA to create double-stranded breaks in complementary DNA target. Further, double-stranded break repair machinery leads to the intended gene modifications. The CRISPR/Cas9 system is widely used technique for genome modification, editing and other biotechnology applications, such as functional annotation, a system for visualization of specific genomic loci and transcriptional control of genes. CRISPR/Cas9-mediated manipulation of the laboratory animal genomes has contributed to the understanding of gene functions and has become a popular approach for modeling human disorders. Furthermore, the growing application of CRISPR-Cas9 system to human genes emerges as an extremely powerful technology for the molecular characterization and treatment of human disease. In this review we present the essential principles of CRISPR/Cas9 technology and the recent advances in its use in translational biomedicine.

Introduction. Investigation of relationships between interstitial lung diseases (ILD) and development of heart failure would be useful for determining target therapy of heart failure (HF) among such patients. Aims.To study intracardiac hemodynamic and factors associated with its dysfunction among patients with ILD. 40 patients including: 34 with Chronic Hypersensitivity Pneumonitis (HP) and 6 with idiopathic pulmonary fibrosis (IPF). Methods. Pulmonary high-resolution computed tomography, echocardiography, spirometry, diffusing lung capacity for carbon monoxide (DLCO), bodypletysmography, blood oxygen (PaO ) were estimated. Results. 55.9% of patients with HP and all patients with IPF had a «cor pulmonale» with diastolic disfunction (DD), and 40% of them also had systolic dysfunction of right ventricle (RV). DD of left ventricle (LV) of I type was found among 10% of patients. 20% of patients were diagnosed with high pulmonary pressure (PP). The basal diameter of right ventricle (BDRV) correlated with DLCO (r=-0,718, p=0,004), PaO (r=-0,690, p=0,006), lung fibrosis (LF) (r=0,602, p=0,002). Tricuspid Annular Plane Systolic Excursion (TAPSE) correlated with mitral E/E’ ratio, tricuspid E/E’ ratio, total lung capacity (TLC) and LF (r=-0,753, p=0,002). Parameters of DD of RV significantly correlated with BDRV, TLC, DLCO, LF. Mitral E/E’ ratio correlated with DLCO and LF. PP corresponded with DLCO, DD of LV, LF (r=0,536, p=0,03) Conclusions. Correlation of LF with parameters of heart failure makes it one of the targets for ILD therapy as well as HF associated with ILD.

Background Heparan sulfate proteoglycan (HSPG) syndecan-1 (Sdc1) acts as a receptor for triglyceride-rich lipoproteins (TRLs), growth factors, chemokines and enzymes. Due to the disordered structure, its function is as diverse as its ligands. In this paper, we have analyzed hepatic and aortic arch expression of Sdc1 in ApoE-/- mice and examined their association with biochemical changes in plasma during the atheroma formation. Methods ApoE knockout (ApoE-/-) mice as a model of atherosclerosis were used. Plasma chemistry parameters were estimated by automatic biochemical analyzer. The ELISA test was used to detect soluble Sdc1. The mRNA level of syndecan-1 in liver cells and aortic arch was determined by real time PCR. Results The Sdc1 mRNA level in liver cells was 1.5-2.5 times higher in ApoE-/- mice compared to the wild-type species and increased with age, whereas it remained at the same level in wild-type mice upon aging. Furthermore, the plasma cholesterol level was 4-6 times higher in ApoE-/- mice compared to the wild type; in contrast, triglyceride (TG) remained at the same level. Simultaneously, the expression of Sdc1 in the aortic arch of ApoE-/- mice decreases with age; however, it increases in wild-type mice of the same age. We determined that the Sdc1 mRNA expression in liver cells is significantly higher compared to the cells of aortic arch. In addition, our research demonstrated that the level of soluble Sdc1 slightly increased with age and did not depend on mouse genotype; yet, the total amount of soluble Sdc1 was higher in ApoE-/- mice. Conclusion Our data suggest that the level of soluble Sdc1 in serum of mice can be associated with chronic inflammation. In addition, we hypothesized that a compensatory increase in the Sdc1 expression in ApoE-/- mice may prevent accumulation of triglycerides in serum, yet having no effect on cholesterol accumulation.

Syndecans are transmembrane heparan sulfate proteoglycans involved in the regulation of cell growth, differentiation, adhesion, neuronal development, and lipid metabolism. Syndecans are expressed in a tissue-specific manner to facilitate diverse cellular processes. As receptors and co-receptors, syndecans provide promising therapeutic targets that bind to a variety of physiologically important ligands. Negatively charged glycosaminoglycan chains of syndecans, located in the extracellular compartment, are critical for such binding. Functions of syndecans are as diverse as their ligands. For example, hepatic syndecan-1 mediates clearance of triglyceride-rich lipoproteins. Syndecan-2 promotes localization of Alzheimer's amyloid Aβ peptide to the cell surface, which is proposed to contribute to amyloid plaque formation. Syndecan-3 helps co-localize the appetite-regulating melanocortin-4 receptor with its agonist, leading to an increased appetite. Finally, syndecan-4 initiates the capture of modified low-density lipoproteins by macrophages and thereby promotes the atheroma formation. We hypothesize that syndecan modifications such as desulfation of glycosaminoglycan chains may contribute to a wide range of diseases, from atherosclerosis to type 2 diabetes. At the same time, desulfated syndecans may have beneficial effects, as they can inhibit amyloid plaque formation or decrease the appetite. Despite considerable progress in understanding diverse functions of syndecans, the complex physiological roles of this intriguing family of proteoglycans are far from clear. Additional studies of syndecans may potentially help develop novel therapeutic approaches and diagnostic tools to alleviate complex human diseases such as cardiovascular and Alzheimer's diseases.

Because intrinsically disordered proteins are incapable of forming unique tertiary structures in isolation, their interaction with partner structures enables them to play important roles in many different biological functions. Therefore, such proteins are usually multifunctional, and their ability to perform their major function, as well as accessory functions, depends on the characteristics of a given interaction. The present paper demonstrates, using predictions from two programs, that the transmembrane proteoglycans syndecans are natively disordered because of their diverse functions and large number of interaction partners. Syndecans perform multiple functions during development, damage repair, tumor growth, angiogenesis, and neurogenesis. By mediating the binding of a large number of extracellular ligands to their receptors, these proteoglycans trigger a cascade of reactions that subsequently regulate various cell processes: cytoskeleton formation, proliferation, differentiation, adhesion, and migration. The occurrences of 20 amino acids in syndecans 1–4 from 25 animals were compared with those in 17 animal proteomes. Gly + Ala, Thr, Glu, and Pro were observed to predominate in the syndecans, contributing to the lack of an ordered structure. In contrast, there were many fewer amino acids in syndecans that promote an ordered structure, such as Cys, Trp, Asn, and His. In addition, a region rich in Asp has been identified between two heparan sulfate-binding sites in the ectodomains, and a region rich in Lys has been identified in the conserved C1 site of the cytoplasmic domain. These particular regions play an essential role in the various functions of syndecans due to their lack of structure.

Syndecans are transmembrane heparan sulfate proteoglycans involved in the regulation of cell growth, differentiation, adhesion, neuronal development, and lipid metabolism. Syndecans are expressed in a tissue-specific manner to facilitate diverse cellular processes. As receptors and co-receptors, syndecans provide promising therapeutic targets that bind to a variety of physiologically important ligands. Negatively charged glycosaminoglycan chains of syndecans, located in the extracellular compartment, are critical for such binding. Functions of syndecans are as diverse as their ligands. For example, hepatic syndecan-1 mediates clearance of triglyceride-rich lipoproteins. Syndecan-2 promotes localization of Alzheimer’s amyloid Aβ peptide to the cell surface, which is proposed to contribute to amyloid plaque formation. Syndecan-3 helps co-localize the appetite-regulating melanocortin-4 receptor with its agonist, leading to an increased appetite. Finally, syndecan-4 initiates the capture of modified low-density lipoproteins by macrophages and thereby promotes the atheroma formation. We hypothesize that syndecan modifications such as desulfation of glycosaminoglycan chains may contribute to a wide range of diseases, from atherosclerosis to type 2 diabetes. At the same time, desulfated syndecans may have beneficial effects, as they can inhibit amyloid plaque formation or decrease the appetite. Despite considerable progress in understanding diverse functions of syndecans, the complex physiological roles of this intriguing family of proteoglycans are far from clear. Additional studies of syndecans may potentially help develop novel therapeutic approaches and diagnostic tools to alleviate complex human diseases such as cardiovascular and Alzheimer’s diseases.