Antiparasitic Effects of Sulfated Polysaccharides from Marine Hydrobionts

This review presents materials characterizing sulfated polysaccharides (SPS) of marine hydrobionts (algae and invertebrates) as potential means for the prevention and treatment of protozoa and helminthiasis. The authors have summarized the literature on the pathogenetic targets of protozoa on the host cells and on the antiparasitic potential of polysaccharides from red, brown and green algae as well as certain marine invertebrates. Information about the mechanisms of action of these unique compounds in diseases caused by protozoa has also been summarized. SPS is distinguished by high antiparasitic activity, good solubility and an almost complete absence of toxicity. In the long term, this allows for the consideration of these compounds as effective and attractive candidates on which to base drugs, biologically active food additives and functional food products with antiparasitic activity.     

Autoreactive B cell responses to RNA-related antigens due to TLR7 gene duplication

Antibodies against nuclear self-antigens are characteristic of systemic autoimmunity, although mechanisms promoting their generation and selection are unclear. Here, we report that B cells containing the Y-linked autoimmune accelerator (Yaa) locus are intrinsically biased toward nucleolar antigens because of increased expression of TLR7, a single-stranded RNA-binding innate immune receptor. The TLR7 gene is duplicated in Yaa mice because of a 4-Megabase expansion of the pseudoautosomal region. These results reveal high divergence in mouse Y chromosomes and represent a good example of gene copy number qualitatively altering a polygenic disease manifestation.     

Effects of castration-induced visceral obesity and antioxidant treatment on lipid profile and insulin sensitivity in New Zealand white rabbits

Molecular mechanisms, responsible for the impaired insulin-sensitivity state due to the obesity are not fully understood in both humans and animals. The purpose of this study was to investigate the effects of castration-induced visceral obesity and the influence of two antioxidants on constituents of blood lipid profile and insulin sensitivity in New Zealand white rabbits. Twenty-six clinically healthy male New Zealand white rabbits were used in the experiment and were divided into 3 groups: first group (CI, n = 7) - castrated-obese and treated with antioxidants “Immunoprotect” for 2 months; second group (CO, n = 7) - castrated-obese; third group (NC, n = 12) - control group (non-castrated, non-obese). At the end of the follow-up period of 2 months after castration an intravenous glucose tolerance test (IVGTT) was performed after a 12-h fasting period as the blood samples for determination of glucose and insulin and their kinetic parameters were obtained at 5 and 0 min before and at 5, 10, 30, 60 and 120 min after the infusion of the glucose. The constituents of lipid profile, triglycerides (TG), total cholesterol (TC) and HDL-cholesterol (HDL-C) were also assessed in the overnight fasting blood samples. The body weight (BW), body mass index (BMI), amount of the visceral fat (VF) and VF/BW ratio were both measured and calculated before the IVGTT and at the end of the experimental period. All measured markers of obesity (BW, BMI, VF, VF/BW) were significantly higher in both groups of castrated rabbits than in the control group. Apart HDL-C, the plasma concentrations of all constituents of lipid profile (TG, TC, HDL-C) were the highest in CO group. There were generally no differences between CI and NC groups for the same traits. After glucose injection blood glucose concentrations and glucose and insulin kinetic parameters were considerably higher (except of glucose elimination rate) in CO rabbits than in NC ones. Castrated rabbits treated with “Immunoprotect” showed lower fasting plasma insulin and improved glucose kinetics dynamics than CO rabbits, but commensurable values of glucose and insulin kinetics parameters than NC group. The results of the current study clearly indicated that castration-induced visceral obesity affected negatively the lipid profile and insulin sensitivity and/or responsiveness. Treatment with antioxidant supplementation, consisted of d-limonene and vitamin E, improved blood lipid profile, fatty liver, glucose homeostasis and insulin sensitivity in obese rabbits. In addition, based on our results we may suggest that castrated male New Zealand white rabbits might be considered as an appropriate animal model to study various metabolic abnormalities related to visceral obesity, such as dyslipidemia and impaired insulin sensitivity.     

Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH) families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases.     

Fucoidans as Potential Inhibitors of HIV-1

The antiviral activity of different structure fucoidans (α-l-fucans and galactofucans) was studied using two model viral systems based on a lentiviral vectors and a replication competent Moloney murine leukemia virus (Mo-MuLV). It was found that investigated fucoidans have no cytotoxic effects on Jurkat and SC-1cell at the concentration range of 0.001–100 µg/mL. Fucoidans with different efficiency suppressed transduction of Jurkat cell line by pseudo-HIV-1 particles carrying the envelope protein of HIV-1 and infection of SC-1 cells by Mo-MuLV. According to our data, all natural fucoidans can be considered as potential anti-HIV agents regardless of their carbohydrate backbone and degree of sulfating, since their activity is shown at low concentrations (0.001–0.05 µg/mL). High molecular weight fucoidans isolated from Saccharina cichorioides (1.3-α-l-fucan), and S. japonica (galactofucan) were the most effective inhibitors.     

Anticancer and Cancer Preventive Properties of Marine Polysaccharides: Some Results and Prospects

Many marine-derived polysaccharides and their analogues have been reported as showing anticancer and cancer preventive properties. These compounds demonstrate interesting activities and special modes of action, differing from each other in both structure and toxicity profile. Herein, literature data concerning anticancer and cancer preventive marine polysaccharides are reviewed. The structural diversity, the biological activities, and the molecular mechanisms of their action are discussed.     

Pools and fluxes of biogenic carbon in the Former Soviet Union

The Former Soviet Union (FSU) was the largest country in the world. It occupied one-sixth of the land surface of the Earth. An understanding of the pools and fluxes of biogenic C in the FSU is essential to the development of international strategies aimed at mitigation of the negative impacts of global climate change. The territory of the FSU is represented by a variety of climate conditions. The major part of the FSU territory is in the boreal and temperate climatic zones. The climate in the FSU changes from arctic and subarctic in the North to subtropical and desert in the South. From west to east, the climate makes a transition from maritime to continental to monsoon. The vegetation of the FSU includes the following principal types: forest, woodland, shrubland, grassland, tundra, desert, peatlands and cultivated land. Arctic deserts and tundra formations are found in the northern part of the FSU; deserts and semi-deserts are found in the southern part.     

Substitution of Hordeum marinum ssp. gussoneanum chromosome 7HL into wheat homoeologous group-7

Ditelosomic (Dt) 7HL^mar(7D) and monotelosomic (Mt) 7HL^mar(7A) and 7HL^mar(7B) wheat–barley substitution lines were developed by crossing monosomic 7A, 7B and 7D lines of common wheat cv. Saratovskaya 29 with disomic wheat–barley addition lines (2n = 44) that carry telocentric chromosomes 7HL^mar from Hordeum marinum ssp. gussoneanum 4×. Genomic in situ hybridisation confirmed the presence of barley chromosomes in the wheat genome. The compensating ability of the telosome in each combination was assessed by its transmission rate to progenies of plants with 2n = 41 + t chromosomes. Seed set and transmission rates of the telosome depended on the identity of the competing wheat homoeologue. Of the three chromosomes wheat, the telosome 7HL^mar compensated better for chromosome 7D and poorly for 7B. These and other data are discussed with respect to the phylogenetic relationships between the wheat chromosomes of group 7 and the chromosome of H. marinum, and the practical utility of these lines for wheat improvement is evaluated.