Volume 72, Nº 2 (2017)

There exist numerous experimental and epidemiological data indicating that malnutrition in early development may influence the risk of developing metabolic disorders in adult life, including type 2 diabetes mellitus (T2DM). Epidemiological evidence for such a relationship was mostly obtained in quasi-experimental studies (natural experiments) carried out on the populations of different countries. These studies revealed that exposure to famine in prenatal and/or early postnatal development is associated with increased risk of developing type 2 diabetes in adult life. Epigenetic regulation of gene activity is considered to be the main mechanism linking starvation in early life and increased risk of type 2 diabetes in adulthood. It is believed that exposure to famine during pregnancy may induce persistent epigenetic variations that are thought to have some adaptive value in the early postnatal development but that also lay grounds for metabolic disorders, including type 2 diabetes, in later life. The present review consolidates and discusses the data indicating the possibility of early developmental programming of type 2 diabetes obtained in the course of quasi-experimental studies.

Diatom species composition in the ice of Velikaya Salma strait of Kandalaksha Bay of the White Sea was studied in 5 stations in March, 2013–2014—prior to the spring algal bloom. Under-ice water salinity and ice thickness did not differ significantly between the two years. In total 59 diatom taxa (47 species and 12 taxa of higher taxonomic ranks) were found in the ice of Velikaya Salma strait, which makes 61% of the number of diatom taxa found in Velikaya Salma ice during the whole ice period and 22% of all the White Sea ice species. Species Stenoneis obtuserostrata (Hustedt) Poulin and Gyrosigma concilians (Cleve) Okolodkov were identified in the White Sea ice for the first time. Szymkiewicz-Simpson similarity coefficient for pairs of stations with significant difference was 0.44–0.80.

Early stage interactions between the powdery mildew pathogen and a host plant are studied. Treatment of wheat leaves with various concentrations of hydrogen peroxide and 3-amino-1,2,4-triazole resulted in the formation of morphological anomalies of germ tubes and nonviable colonies on host plant leaves. The observed effect of oxidative stress on germination anomalies of powdery mildew is similar to previously reported interactions between the pathogen and mildew resistant plants. We conclude that abnormal infectious structure formation of wheat powdery mildew may be associated with increased presence of reactive oxygen species during plant defense responses.

Production and application of therapeutic monoclonal antibodies are second only to vaccines in the world pharmaceutical market. The most common therapeutic antibodies are monoclonal antibodies (mAbs) of the IgG isotype that are produced in eukaryotic CHO cells. In recent years, there has been a considerable interest in developing treatment medications based on IgA antibodies, which can have a wide range of effector functions on human mucous membranes. To study the expression level of immunoglobulin A (IgA) in mammal cells, we designed a set of bipromoter (CMV and EF1α) vectors. The vectors contain gene fragments that encode the heavy chain variable domain (VH) and the light chain variable domain (VL) of the human monoclonal antibody FI6v3 against the hemagglutinin of influenza virus A. They also contain gene fragments that encode the light chain (kappa type) constant domain and the heavy chain constant domain of the human antibody IgA1. The expression vectors differed in the orientation of the promoters and the presence or absence of introns. Two variants of the full-length light and heavy chains were cloned into a eukaryotic expression vector in head-to-head and head-to-tail orientations. The resulting plasmids were transfected into CHO-DG44 and HEK-293T cells. The antibody expression level for the stable transfection of CHO-DG44 and HEK-293T cell cultures was determined by ELISA. The results of the experiments showed that the expression of FI6v3-IgA1 antibodies significantly increased when eukaryotic cells were transfected with the plasmid pBiPr-ABIgA1FI6-Iht in which the heavy chain of IgA1 contains introns and the promoters are arranged head-to-tail.

The ion-exchange properties of cell wall polymers isolated from the roots of wheat (Triticum aestivum L.) plants grown on either nitrate-free (N-deficient) or nitrate-containing (+N) hydroponic nutrient medium have been investigated. Irrespective of the nitrogen nutrition regimen, the studied cell walls contained four types of ion-exchange groups: primary amino groups of structural proteins (pK_a < 3), carboxyl groups of polygalacturonic acid in pectin (pK_a ~4.7), carboxyl groups of hydroxycinnamic acids (pK_a ~7.3), and phenolic OH-groups of lignin (pK_a ~10.2). The quantitative ratio between these types of ion-exchange groups, the mass fraction of cell walls in the dry weight of roots, and the swelling coefficient of cell walls depended on the nitrate presence in the growing medium. Compared to the +N variant, the N-deficient variant was characterized by a 2.4 times higher content of phenolic OH-groups in cell walls and 1.24 times higher mass fraction of cell walls; at the same time, the swelling coefficient for this variant was lower by 10%. The obtained data indicate that nitrogen deficiency results in a formation of thicker root cell walls with a higher degree of polymer cross-linking that may be caused by the increased lignin content.

Functional characterization of new short glyproline peptides, which are able to provide a regulatory effect on the functional state of the hemostasis system, as well as lipid and carbohydrate metabolism in the body, is an actual task of physiology and medicine. In the present study, we used a model of experimental metabolic syndrome developed in animals due to continuous feeding with high-calorie food. This leads to increased clotting, glucose concentration, low-density lipoprotein cholesterol, triglycerides, and the level of total cholesterol in the blood, which is accompanied by an increase in the body weight of rats. Arginine-containing peptides (Arg-Glu-Arg-Pro-Gly-Pro, Arg-Glu-Arg-Val-Gly-Pro, Arg-Glu-Arg-Gly-Pro) were intranasally administered every 24 h to rats seven times 6 weeks after the development of metabolic syndrome. These peptides provided a unique combined effect on the body, restoring parameters of lipid metabolism, the hemostasis system, and the concentration of blood glucose to normal values. The corrective effect of the studied peptides was detected 20 h after the last administration and was maintained for 168 h even under further feeding of rats with high-calorie diet. The studied glyproline peptides belong to therapeutic normoglycemic and lipid-lowering drugs. They block the accumulation of new fat deposits in the body, and also have anticoagulant and antithrombotic effects in disorders of lipid metabolism. The Arg-Glu-Arg-Pro-Gly-Pro peptide possessed the most pronounced and stable positive effect on the body.

Substrate topography influences cell shape, direction and rate of migration, nucleus shape, and gene expression levels. This influence is commonly studied using substrates with predefined surface structure and chemical composition. In the current work, we studied the state of HaCaT keratinocyte nuclei and actin cytoskeleton on poly(ε-caprolactone) scaffolds obtained by electrospinning. Two types of fibrous scaffolds were prepared and characterized. In the random scaffolds, the fibers were arranged in a nonsystematic fashion; however, most of the fibers had the same direction in the aligned scaffolds. When cultured on the aligned scaffolds, HaCaT cells exhibited oriented actin filaments and had more elongated nuclei.

Dynamics of carbon dioxide exchange in the Common Spruce (Picea abies L.) in relation to environmental factors was monitored during several seasons. Direct linear dependence of photosynthesis rate from the levels of air temperature and illumination was found, and correlation coefficients were 0.860 (p < 0.001) and 0.704 (p < 0.001). It was found that seasonal maximum of net photosynthesis production was attained at temperatures of 23–25°C. A decrease in temperature optimum was associated with reduction of the CO₂ assimilation intensity level. The impact of environmental factors on photosynthesis intensity is discussed in terms of the developed model. Using this model, we demonstrated that temperature and illumination dynamics in toto accounts for 82% of changes in photosynthesis rate. It is the air temperature that exerts the strongest influence on the process of photosynthesis. According to our calculations, the net photosynthesis level was three times higher than the level of respiration. This is indicative of a positive carbon dioxide balance in the needles of the Common Spruce.