11 research outputs found

    Selective Role of TNFα and IL10 in Regulation of Barrier Properties of the Colon in DMH-Induced Tumor and Healthy Rats

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    Recently it has been reported that the tumor adjacent colon tissues of 1,2-dymethylhydrazine induced (DMH)-rats revealed a high paracellular permeability. We hypothesized that the changes might be induced by cytokines. Colorectal cancer is accompanied by an increase in tumor necrosis factor alpha (TNFα) and interleukin 10 (IL10) that exert opposite regulatory effects on barrier properties of the colon, which is characterized by morphological and functional segmental heterogeneity. The aim of this study was to analyze the level of TNFα and IL10 in the colon segments of DMH-rats and to investigate their effects on barrier properties of the proximal and distal parts of the colon in healthy rats. Enzyme immunoassay analysis showed decreased TNFα in tumors in the distal part of the colon and increased IL10 in proximal tumors and in non-tumor tissues. Four-hour intraluminal exposure of the colon of healthy rats with cytokines showed reduced colon barrier function dependent on the cytokine: TNFα decreased it mainly in the distal part of the colon, whereas IL10 decreased it only in the proximal part. Western blot analysis revealed a more pronounced influence of IL10 on tight junction (TJ) proteins expression by down-regulation of the TJ proteins claudin-1, -2 and -4, and up-regulation of occludin only in the proximal part of the colon. These data may indicate a selective role of the cytokines in regulation of the barrier properties of the colon and a prominent role of IL10 in carcinogenesis in its proximal part

    Prednisolone Targets Claudins in Mouse Brain Blood Vessels

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    Endothelial cells in brain capillaries are crucial for the function of the blood–brain barrier (BBB), and members of the tight junction protein family of claudins are regarded to be primarily responsible for barrier properties. Thus, the analysis of bioactive substances that can affect the BBB’s permeability is of great importance and may be useful for the development of new therapeutic strategies for brain pathologies. In our study, we tested the hypothesis that the application of the glucocorticoid prednisolone affects the murine blood–brain barrier in vivo. Isolated brain tissue of control and prednisolone-injected mice was examined by employing immunoblotting and confocal laser scanning immunofluorescence microscopy, and the physiological and behavioral effects were analyzed. The control tissue samples revealed the expression of barrier-forming tight junction proteins claudin-1, -3, and -5 and of the paracellular cation and water-channel-forming protein claudin-2. Prednisolone administration for 7 days at doses of 70 mg/kg caused physiological and behavioral effects and downregulated claudin-1 and -3 and the channel-forming claudin-2 without altering their localization in cerebral blood vessels. Changes in the expression of these claudins might have effects on the ionic and acid–base balance in brain tissue, suggesting the relevance of our findings for therapeutic options in disorders such as cerebral edema and psychiatric failure

    Circulating Ouabain Modulates Expression of Claudins in Rat Intestine and Cerebral Blood Vessels

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    The ability of exogenous low ouabain concentrations to affect claudin expression and therefore epithelial barrier properties was demonstrated previously in cultured cell studies. We hypothesized that chronic elevation of circulating ouabain in vivo can affect the expression of claudins and tight junction permeability in different tissues. We tested this hypothesis in rats intraperitoneally injected with ouabain (1 ÎĽg/kg) for 4 days. Rat jejunum, colon and brain frontal lobes, which are variable in the expressed claudins and tight junction permeability, were examined. Moreover, the porcine jejunum cell line IPEC-J2 was studied. In IPEC-J2-cells, ouabain (10 nM, 19 days of incubation) stimulated epithelial barrier formation, increased transepithelial resistance and the level of cSrc-kinase activation by phosphorylation, accompanied with an increased expression of claudin-1, -5 and down-regulation of claudin-12; the expression of claudin-3, -4, -8 and tricellulin was not changed. In the jejunum, chronic ouabain increased the expression of claudin-1, -3 and -5 without an effect on claudin-2 and -4 expression. In the colon, only down-regulation of claudin-3 was observed. Chronic ouabain protected the intestine transepithelial resistance against functional injury induced by lipopolysaccharide treatment or by modeled acute microgravity; this regulation was most pronounced in the jejunum. Claudin-1 was also up-regulated in cerebral blood vessels. This was associated with reduction of claudin-3 expression while the expression of claudin-5 and occludin was not affected. Altogether, our results confirm that circulating ouabain can functionally and tissue-specifically affect barrier properties of epithelial and endothelial tissues via Na,K-ATPase-mediated modulation of claudins expression

    Genome-wide association studies targeting the yield of extraembryonic fluid and production traits in Russian White chickens

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    Background: The Russian White is a gene pool breed, registered in 1953 after crossing White Leghorns with local populations and, for 50 years, selected for cold tolerance and high egg production (EL). The breed has great potential in meeting demands of local food producers, commercial farmers and biotechnology sector of specific pathogen-free (SPF) eggs, the former valuing the breed for its egg weight (EW), EL, age at first egg (AFE), body weight (BW), and the latter for its yield of extraembryonic fluid (YEF) in 12.5-day embryos, ratio of extraembryonic fluid to egg weight, and embryo mass. Moreover, its cold tolerance has been presumably associated with day-old chick down colour (DOCDC) white rather than yellow, the genetic basis of these traits being however poorly understood. Results: We undertook genome-wide association studies (GWASs) for eight performance traits using single nucleotide polymorphism (SNP) genotyping of 146 birds and an Illumina 60KBeadChip. Several suggestive associations (p <5.16*10(-5)) were found for YEF, AFE, BW and EW. Moreover, on chromosome 2, an association with the white DOCDC was found where there is an linkage disequilibrium block of SNPs including genes that are responsible not for colour, but for immune resistance. Conclusions: The obtained GWAS data can be used to explore the genetics of immunity and carry out selection for increasing YEF for SPF eggs production.Peer reviewe

    The Groundhog Day stock market anomaly

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    This paper discovers a distinct calendar anomaly on the US stock market associated with the Groundhog Day prognostication tradition across 1928-2021. There are significant positive abnormal returns around the “prediction” of an early spring, while buy-and-hold returns around the “prediction” of a long winter are 2.78% lower. The results are robust in subsamples, to a set of placebo tests for international stock indices, and cannot be explained by January effect, the “Halloween Indicator”, turn-of-the-month effect, or other seasonalities. The findings imply major and persistent irrational optimism of US investors revolving around Groundhog Day early spring prognostications

    Ecosystem services of soil microorganisms and microbiological component condition assessment of the quarry Pechurki.

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    The obligatory component of any biogeocenosis is soil microorganisms, which perform a number of cruical metabolic and ecophysiological functions. They participate in plant cover recovery and in circulation of elements, promote maintaining of soil fertility and regulate parts of humification. The prime role of soil biota in a root delivery of plants consists in returning nutrients to their mineral forms, which plants can take up again. Soil microorganisms are shown to influence acid-base balance stabilization and transformation of root exudates. The decrease of toxic substances negative consequences level on biogeocenoses components was also established. Soil formation criterion is the biological soils condition which is estimated on microbiological activity. In stability maintaining of communities and ecosystems development an important role is played by a condition of replantozem microbiocenoses though it has not been studied. It is relevant to study the microbiological component condition at the technogenic habitats. The aim of this research was to assess the quantitative maintenance of a microbial component and its activity in the quarry Pechurki. The microbial biomass content varied from 0,98 to 4,6 microg C/g of the soil, values increase with overgrowing term. In Cmik value the studied samples can be arranged in this row: underlay&gt; organomineral horizon&gt; rock. Values of the microbial metabolic coefficient was not higher than 0,021 microg СO2–С/mg Сmic per hour, what is showing an instable functioning of microbial societies. Thus the restitution of microbiological activity of disturbed lands is slowed down considerably and does not depend on the type of substrate and the plant community. The received results shown the low stability of microbial societies and the ineffectiveness of using the organic substrate, especially in the first stage of quarry overgrowing. In order to analyze succession of soil microbial communities investigation of metagenomics of soil samples has been conducted. Taxonomic analysis of communities at the phyla level did not reveal differences between different age dumps. In all cases, the largest phyla was the Proteobacteria (55.7%), Actinobacteria (17.0%), Bacteroidetes (10.3%), Acidobacteria (6.4%), and Chloroflexi (3.8%). The dominant taxa in young dumps were Acinetobacter (8.8% of the total community), Micrococcaceae (8%) and Pseudomonas (6%). In the middle-aged dumps, representatives of Micrococcaceae (4.5%) and Sphingomonadaceae (1.4%) prevailed. Old age dumps showed a high proportion of representatives of Bradyrhizobiaceae (5%), Chitinophagaceae (2.9%) and Hyphomicrobiaceae (2.5%) in the community. This work was supported by Russian Scientific Foundation, project № 17-16-01030 “Soil biota dynamics in chronoseries of posttechnogenic landscapes: analyses of soil-ecological effectiveness of ecosystems restoration”peerReviewe

    Selective Role of TNF&alpha; and IL10 in Regulation of Barrier Properties of the Colon in DMH-Induced Tumor and Healthy Rats

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    Recently it has been reported that the tumor adjacent colon tissues of 1,2-dymethylhydrazine induced (DMH)-rats revealed a high paracellular permeability. We hypothesized that the changes might be induced by cytokines. Colorectal cancer is accompanied by an increase in tumor necrosis factor alpha (TNF&alpha;) and interleukin 10 (IL10) that exert opposite regulatory effects on barrier properties of the colon, which is characterized by morphological and functional segmental heterogeneity. The aim of this study was to analyze the level of TNF&alpha; and IL10 in the colon segments of DMH-rats and to investigate their effects on barrier properties of the proximal and distal parts of the colon in healthy rats. Enzyme immunoassay analysis showed decreased TNF&alpha; in tumors in the distal part of the colon and increased IL10 in proximal tumors and in non-tumor tissues. Four-hour intraluminal exposure of the colon of healthy rats with cytokines showed reduced colon barrier function dependent on the cytokine: TNF&alpha; decreased it mainly in the distal part of the colon, whereas IL10 decreased it only in the proximal part. Western blot analysis revealed a more pronounced influence of IL10 on tight junction (TJ) proteins expression by down-regulation of the TJ proteins claudin-1, -2 and -4, and up-regulation of occludin only in the proximal part of the colon. These data may indicate a selective role of the cytokines in regulation of the barrier properties of the colon and a prominent role of IL10 in carcinogenesis in its proximal part

    Dose- and Segment-Dependent Disturbance of Rat Gut by Ionizing Radiation: Impact of Tight Junction Proteins

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    The damaging effect of ionizing radiation (IR) exposure results in the disturbance of the gut natural barrier, followed by the development of severe gastrointestinal injury. However, the dose and application segment are known to determine the effects of IR. In this study, we demonstrated the dose- and segment-specificity of tight junction (TJ) alteration in IR-induced gastrointestinal injury in rats. Male Wistar rats were subjected to a total-body X-ray irradiation at doses of 2 or 10 Gy. Isolated jejunum and colon segments were tested in an Ussing chamber 72 h after exposure. In the jejunum, 10-Gy IR dramatically altered transepithelial resistance, short-circuit current and permeability for sodium fluorescein. These changes were accompanied by severe disturbance of histological structure and total rearrangement of TJ content (increased content of claudin-1, -2, -3 and -4; multidirectional changes in tricellulin and occludin). In the colon of 10-Gy irradiated rats, lesions of barrier and transport functions were less pronounced, with only claudin-2 and -4 altered among TJ proteins. The 2-Gy IR did not change electrophysiological characteristics or permeability in the colon or jejunum, although slight alterations in jejunum histology were noted, emphasized with claudin-3 increase. Considering that TJ proteins are critical for maintaining epithelial barrier integrity, these findings may have implications for countermeasures in gastrointestinal acute radiation injury

    Technology of semi-hard cheese using protein fat simulator

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    The annual increase in the production of protein-sensitive dairy products leads to an increase in the available amount of their by-product of production – whey. A promising direction in the implementation of its biotechnological potential is the production of a protein imitator of the fat properties – whey protein microparticulate. The aim of this work was to study the possibility of its use in the technology of semi-hard cheeses. The introduction of a fat simulator in a normalized mixture changes its composition, including the ratio of protein fractions, the ratio of fat to protein, and calcium content. With a mass fraction of microparticulate more than 10 %, a flabby clot forms, which is extremely difficult to undergo further processing to obtain elastic cheese grain. High hydration of whey proteins increases the moisture content in the cheese mass after pressing and in the ripening process. Hydrolysis of paracasein and its fractions proceeds more intensively in the cheese with fat simulator. The developed product is characterized by a higher value of the moisture content, which, together with the preservation of the protein clot particles of the simulator by the mesh structure, increases the yield of cheese

    Chronic Ouabain Prevents Radiation-Induced Reduction in the &alpha;2 Na,K-ATPase Function in the Rat Diaphragm Muscle

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    The damaging effect of ionizing radiation (IR) on skeletal muscle Na,K-ATPase is an open field of research. Considering a therapeutic potential of ouabain, a specific ligand of the Na,K-ATPase, we tested its ability to protect against the IR-induced disturbances of Na,K-ATPase function in rat diaphragm muscle that co-expresses the &alpha;1 and &alpha;2 isozymes of this protein. Male Wistar rats (n = 26) were subjected to 6-day injections of vehicle (0.9% NaCl) or ouabain (1 &micro;g/kg/day). On the fourth day of injections, rats were exposed to one-time total-body X-ray irradiation (10 Gy), or a sham irradiation. The isolated muscles were studied 72 h post-irradiation. IR decreased the electrogenic contribution of the &alpha;2 Na,K-ATPase without affecting its protein content, thereby causing sarcolemma depolarization. IR increased serum concentrations of ouabain, IL-6, and corticosterone, decreased lipid peroxidation, and changed cellular redox status. Chronic ouabain administration prevented IR-induced depolarization and loss of the &alpha;2 Na,K-ATPase electrogenic contribution without changing its protein content. This was accompanied with an elevation of ouabain concentration in circulation and with the lack of IR-induced suppression of lipid peroxidation. Given the crucial role of Na,K-ATPase in skeletal muscle performance, these findings may have therapeutic implications as countermeasures for IR-induced muscle pathology
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