Purpose: The aim of the study was to investigate the protective effect of low and high molecular weight beta-glucans on the chosen immunological parameters, markers of antioxidative potential in rats’ colon tissue, the number of lactic acid bacteria (LAB) and the concentration of short-chain fatty acids (SCFA) in rats’ faeces. Methods: The experiment was carried out on 72 8-week old male Sprague–Dawley rats: control (n = 36) and experimental (n = 36). In half of the animals from each group enteritis was induced by LPS (10 mg kg⁻¹). Rats from the experimental group were divided into two groups receiving high (GI) or low (GII) molecular weight beta-glucans for 6 consecutive weeks. Results: LPS evoked enteritis in all the treated animals, manifested by changes in the levels of IL-10, IL-12 and TNF-alpha, as well as in the number of intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) in the colon tissue. Dietary supplementation with beta-glucans following LPS treatment partially reversed this effect. The changes in SCFA concentration were noted, indicating an improvement of the fermentation process in the colon. This effect coincided with an increased number of LAB, pointing at the prebiotic properties of beta-glucans. The positive influence of beta-glucans was also manifested by the improved values of antioxidative potential markers (TAS, SOD, GR and GPx activity, TBARS concentration), noted especially in rats with LPS-induced enteritis. This influence was more pronounced in the case of low molecular weight oat beta-glucan (GII). Conclusions: The present study showed a positive effect of beta-glucans, especially the low molecular weight form, on the colon tissue of healthy rats, as well as animals with LPS-induced enteritis.

Canine atopic dermatitis (cAD) is a common chronic and pruritic skin disease in dogs. The development of cAD involves complex interactions between environmental antigens, genetic predisposition and a number of disparate cell types. The aim of the present study was to perform comprehensive analyses of peripheral blood of AD dogs in relation to healthy subjects in order to determine the changes which would be characteristic for cAD. The number of cells in specific subpopulations of lymphocytes was analyzed by flow cytometry, concentration of chosen pro- and anti-inflammatory cytokines (IL-4, IL-10, IL-13, TNF-α, TGF-β1) was determined by ELISA; and microarray analysis was performed on RNA samples isolated from peripheral blood nuclear cells of AD and healthy dogs. The number of Th cells (CD3+CD4+) in AD and healthy dogs was similar, whereas the percentage of Tc (CD3+CD8+) and Treg (CD4+CD25+ Foxp3+) cells increased significantly in AD dogs. Increased concentrations of IL-13 and TNF-α, and decreased levels of IL-10 and TGF-β1 was observed in AD dogs. The level of IL-4 was similar in both groups of animals. Results of the microarray experiment revealed differentially expressed genes involved in transcriptional regulation (e.g., transcription factors: SMAD2, RORA) or signal transduction pathways (e.g., VEGF, SHB21, PROC) taking part in T lymphocytes lineages differentiation and cytokines synthesis. Results obtained indicate that CD8+ T cells, beside CD4+ T lymphocytes, contribute to the development of the allergic response. Increased IL-13 concentration in AD dogs suggests that this cytokine may play more important role than IL-4 in mediating changes induced by allergic inflammation. Furthermore, observed increase in Treg cells in parallel with high concentrations of TNF-α and low levels of IL-10 and TGF-β1 in the peripheral blood of AD dogs point at the functional insufficiency of Treg cells in patients with AD.

EPA and DHA have been reported to have anti-obesity and anti-inflammatory properties. Recent studies revealed that these positive actions of n-3 PUFA at least partially are connected with their influence on metabolism and secretory functions of the adipose tissue. However, their impact on old adipocytes is still poorly understood. Therefore the aim of the present study was to evaluate the influence of EPA and DHA on markers of inflammation in 3T3-L1 cells at different stages of cellular maturation. Young, mature and old differentiated 3T3-L1 adipocytes were cultured for 48 h in the presence of 100 μM EPA, or 50 μM DHA complexed to albumin, whereas in control conditions only albumin was added to the medium. The Oil Red O staining was used to confirm adipocytes differentiation, and measure triglycerides content in cells. The concentration of adipokines (interleukin 6, adiponectin and leptin) in conditioned media was measured using mouse-specific ELISA kits. The fat accumulation in 3T3-L1 adipocytes was positively correlated with their age; however, EPA and DHA did not affect lipid accumulation on any stage of maturation. EPA and DHA increased the concentration of secreted adiponectin when compared with control, but only in the case of young adipocytes (58% and 35%, respectively). Moreover, EPA supplementation increased interleukin 6 concentration in conditioned medium, while DHA exerted an opposite effect on all stages of cellular maturation. Furthermore, EPA treatment increased leptin release from young cells, while DHA did not affect the secretion of this adipokine. In mature 3T3-L1 adipocytes both experimental factors decreased synthesis of leptin; however, in old cells no impact of these PUFA was noted. In summary, age is an important determinant of fat accumulation in adipocytes and affects adipokines secretion by these cells. Moreover, the impact of investigated fatty acids: EPA and DHA on fat cells varies depending on the stage of maturation, and seems to be stronger in young cells than in mature and old ones. Docosahexaenoic acid exerts an anti-inflammatory action; however, on the basis of the obtained data it was not possible to determine whether eicosapentaenoic acid shows anti- or pro-inflammatory properties.