What happens to Bifidobacterium adolescentis and Bifidobacterium longum ssp. longum in an experimental environment with eukaryotic cells?

BACKGROUND: The impact of probiotic strains on host health is widely known. The available studies on the interaction between bacteria and the host are focused on the changes induced by bacteria in the host mainly. The studies determining the changes that occurred in the bacteria cells are in the minority. Within this paper, we determined what happens to the selected Bifidobacterium adolescentis and Bifidobacterium longum ssp. longum in an experimental environment with the intestinal epithelial layer. For this purpose, we tested the bacteria cells' viability, redox activity, membrane potential and enzymatic activity in different environments, including CaCo-2/HT-29 co-culture, cell culture medium, presence of inflammatory inductor (TNF-α) and oxygen. RESULTS: We indicated that the external milieu impacts the viability and vitality of bacteria. Bifidobacterium adolescentis decrease the size of the live population in the cell culture medium with and without TNF-α (p < 0.001 and p < 0.01 respectively). In contrast, Bifidobacterium longum ssp. longum significantly increased survivability in contact with the eukaryotic cells and cell culture medium (p < 0.001). Bifidobacterium adolescentis showed significant changes in membrane potential, which was decreased in the presence of eukaryotic cells (p < 0.01), eukaryotic cells in an inflammatory state (p < 0.01), cell culture medium (p < 0.01) and cell culture medium with TNF-α (p < 0.05). In contrast, Bifidobacterium longum ssp. longum did not modulate membrane potential. Instead, bacteria significantly decreased the redox activity in response to milieus such as eukaryotic cells presence, inflamed eukaryotic cells as well as the culture medium (p < 0.001). The redox activity was significantly different in the cells culture medium vs the presence of eukaryotic cells (p < 0.001). The ability to ß-galactosidase production was different for selected strains: Bifidobacterium longum ssp. longum indicated 91.5% of positive cells, whereas Bifidobacterium adolescentis 4.34% only. Both strains significantly reduced the enzyme production in contact with the eukaryotic milieu but not in the cell culture media. CONCLUSION: The environmental-induced changes may shape the probiotic properties of bacterial strains. It seems that the knowledge of the sensitivity of bacteria to the external environment may help to select the most promising probiotic strains, reduce research costs, and contribute to greater reproducibility of the obtained probiotic effects.

Studies of the Impact of the Bifidobacterium Species on Inducible Nitric Oxide Synthase Expression and Nitric Oxide Production in Murine Macrophages of the BMDM Cell Line.

Bifidobacterium species are one of the most important probiotic microorganisms which are present in both, infants and adults. Nowadays, growing data describing their healthy properties arise, indicating they could act at the cellular and molecular level. However, still little is known about the specific mechanisms promoting their beneficial effects. Nitric oxide (NO), produced by inducible nitric oxide synthase (iNOS), is involved in the protective mechanisms in the gastrointestinal tract, where it can be provided by epithelial cells, macrophages, or bacteria. The present study explored whether induction of iNOS-dependent NO synthesis in macrophages stems from the cellular action of Bifidobacterium species. The ability of ten Bifidobacterium strains belonging to 3 different species (Bifidobacterium longum, Bifidobacterium adolescentis, and Bifidobacterium animalis) to activate MAP kinases, NF-κB factor, and iNOS expression in a murine bone-marrow-derived macrophages cell line was determined by Western blotting. Changes in NO production were determined by the Griess reaction. It was performed that the Bifidobacterium strains were able to induce NF-қB-dependent iNOS expression and NO production; however, the efficacy depends on the strain. The highest stimulatory activity was observed for Bifidobacterium animalis subsp. animals CCDM 366, whereas the lowest was noted for strains Bifidobacterium adolescentis CCDM 371 and Bifidobacterium longum subsp. longum CCDM 372. Both TLR2 and TLR4 receptors are involved in Bifidobacterium-induced macrophage activation and NO production. We showed that the impact of Bifidobacterium on the regulation of iNOS expression is determined by MAPK kinase activity. Using pharmaceutical inhibitors of ERK 1/2 and JNK, we confirmed that Bifidobacterium strains can activate these kinases to control iNOS mRNA expression. Concluding, the induction of iNOS and NO production may be involved in the protective mechanism of action observed for Bifidobacterium in the intestine, and the efficacy is strain-dependent.

Polysaccharide BAP1 of Bifidobacterium adolescentis CCDM 368 is a biologically active molecule with immunomodulatory properties.

Bifidobacteria are among the most common bacteria used for their probiotic properties and their impact on the maturation and function of the immune system has been well-described. Recently, scientific interest is shifting from live bacteria to defined bacteria-derived biologically active molecules. Their greatest advantage over probiotics is the defined structure and the effect independent of the viability status of the bacteria. Here, we aim to characterize Bifidobacterium adolescentis CCDM 368 surface antigens that include polysaccharides (PSs), lipoteichoic acids (LTAs), and peptidoglycan (PG). Among them, Bad368.1 PS was observed to modulate OVA-induced cytokine production in cells isolated from OVA-sensitized mice by increasing the production of Th1-related IFN-γ and inhibition of Th2-related IL-5 and IL-13 cytokines (in vitro). Moreover, Bad368.1 PS (BAP1) is efficiently engulfed and transferred between epithelial and dendritic cells. Therefore, we propose that the Bad368.1 PS (BAP1) can be used for the modulation of allergic diseases in humans. Structural studies revealed that Bad368.1 PS has an average molecular mass of approximately 9,99 × 106 Da and it consists of glucose, galactose, and rhamnose residues that are creating the following repeating unit: →2)-ß-D-Glcp-1→3-ß-L-Rhap-1→4-ß-D-Glcp-1→3-α-L-Rhap-1→4-ß-D-Glcp-1→3-α-D-Galp-(1→n.

Mechanism of Molecular Activity of Yolkin-a Polypeptide Complex Derived from Hen Egg Yolk-in PC12 Cells and Immortalized Hippocampal Precursor Cells H19-7.

Food-derived bioactive peptides able to regulate neuronal function have been intensively searched and studied for their potential therapeutic application. Our previous study showed that a polypeptide complex yolkin, isolated from hen egg yolk as a fraction accompanying immunoglobulin Y (IgY), improved memory and cognitive functions in rats. However, the mechanism activated by the yolkin is not explained. The goal of the present study was to examine what molecular mechanism regulating brain-derived neurotrophic factor (BDNF) expression is activated by the yolkin complex, using in vitro models of PC12 cell line and fetal rat hippocampal cell line H19-7. It was shown that yolkin increased the proliferative activity of rat hippocampal precursor cells H19-7 cells and upregulated the expression/production of BDNF in a cyclic adenosine monophosphate (cAMP)-response element-binding protein (CREB)-dependent manner. Additionally the upregulation of carboxypeptidase E/neurotrophic factor-α1 (CPE/(NF-α1) expression was shown. It was also determined that upregulation of CREB phosphorylation by yolkin is dependent on cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) and phosphoinositide 3-kinases/protein kinase B (PI3K/Akt) signaling pathway activation. Moreover, the impact of yolkin on the level of intracellular Ca2+, nitric oxide, and activation of extracellular signal-regulated kinases 1/2 (ERK 1/2 kinase) was excluded. These results emphasize that yolkin can act comprehensively and in many directions and may participate in the regulation of neurons' survival and activity. Therefore, it seems that the yolkin specimen can be used in the future as a safe, bioavailable, natural nutraceutical helping to improve the cognition of older people.

The NLRP3 inflammasome as a new target in respiratory disorders treatment.

In recent years a continuous increase in new cases of respiratory disorders, such as rhinitis, asthma, and chronic obstructive pulmonary disease (COPD), has been observed. The exact pathomechanism of these diseases is still blurry, resulting in the lack of targeted and effective therapy. The conventional use of treatment strategies, such as antihistamine drugs and/or glucocorticosteroids act mainly symptomatically and have significant side effects. Specific allergen immunotherapy is only useful in the management of specific allergies and selected patients. Therefore, new therapeutic solutions are constantly being sought. The novelty of recent years has been the association between NLRP3 inflammasome activation and the development of airway inflammatory diseases. This seems to be an interesting therapeutic target that may support or even replace traditional therapies in the future. The review presented, discusses the contribution of NLRP3 inflammasome to the development of allergic rhinitis, allergic asthma, and COPD. Moreover, the modulatory properties of probiotics as potential inhibitors of NLRP3 inflammasome are emphasised.

A Novel Mechanism of Macrophage Activation by the Natural Yolkin Polypeptide Complex from Egg Yolk.

Ageing is accompanied by the inevitable changes in the function of the immune system. It provides increased susceptibility to chronic infections that have a negative impact on the quality of life of older people. Therefore, rejuvenating the aged immunity has become an important research and therapeutic goal. Yolkin, a polypeptide complex isolated from hen egg yolks, possesses immunoregulatory and neuroprotective activity. Considering that macrophages play a key role in pathogen recognition and antigen presentation, we evaluated the impact of yolkin on the phenotype and function of mouse bone marrow-derived macrophages of the BMDM cell line. We determined yolkin bioavailability and the surface co-expression of CD80/CD86 using flow cytometry and IL-6, IL-10, TGF-ß and iNOS mRNA expression via real-time PCR. Additionally, the impact of yolkin on the regulation of cytokine expression by MAPK and PI3K/Akt kinases was determined. The stimulation of cells with yolkin induced significant changes in cell morphology and an increase in CD80/CD86 expression. Using pharmaceutical inhibitors of ERK, JNK and PI3K/Akt, we have shown that yolkin is able to activate these kinases to control cytokine mRNA expression. Our results suggest that yolkin is a good regulator of macrophage activity, priming mainly the M1 phenotype. Therefore, it is believed that yolkin possesses significant therapeutic potential and represents a promising possibility for the development of novel immunomodulatory medicine.

Impact of Probiotic Bacteria on Respiratory Allergy Disorders.

Respiratory allergy is a common disease with an increased prevalence worldwide. The effective remedy is still unknown, and a new therapeutic approach is highly desirable. The review elaborates the influence of probiotic bacteria on respiratory allergy prevention and treatment with particular emphasis on the impact of the current methods of their administration - oral and intranasal. The background of the respiratory allergy is complex thus, we focused on the usefulness of probiotics in the alleviation of different allergy factors, in particular involved in pathomechanism, local hypersensitive evidence and the importance of epithelial barrier. In this review, we have shown that (1) probiotic strains may vary in modulatory potential in respiratory allergy, (2) probiotic bacteria are beneficial in oral and intranasal administration, (3) recombinant probiotic bacteria can modulate the course of respiratory allergy.

The Effectiveness of Probiotics in the Treatment of Inflammatory Bowel Disease (IBD)-A Critical Review.

Inflammatory bowel disease (IBD), which affects millions of people worldwide, includes two separate diseases: Crohn's disease (CD) and ulcerative colitis (UC). Although the background (chronic inflammatory state) and some of the symptoms of CD and UC are similar, both diseases differ from each other. It is becoming clear that a combination of many factors, in particular genetic background, host immune response and microbial reduced diversity status are associated with IBD. One potential strategy to prevent/treat IBD is gut modulation by probiotics. Over the last twenty years, many publications have focused on the role of probiotics in the course of IBD. The review discusses the utility of different strains of probiotics, especially Bifidobacterium spp., in all factors potentially involved in the etiology of IBD. The probiotic modulatory properties among different study models (cell lines, animal models of colitis, clinical study) are discussed and probiotic usefulness is assessed in relation to the treatment, prevention, and remission of diseases.

Coagulation abnormalities identified by thromboelastometry in patients with severe sepsis: the relationship to endotoxemia and mortality.

The aim of this study was to monitor the development of coagulation abnormalities in patients with severe sepsis using thromboelastometry and to assess whether increased endotoxin activity was associated with a change in coagulation. Data collected on ICU admission, day 2, 3, and 4 were analysed in 61 patients. Thromboelastometry made it possible to identify patients with a normal (group 1), hypercoagulable (group 2), or hypocoagulable (group 3) pattern. The best accuracy of thromboelastometry parameters as potential indices of coagulation abnormalities was yielded by the clot formation time and maximum clot firmness. The mortality rate was low in group 1(16%) and the presence of abnormalities, indicating either a hyper or hypocoagulation pattern, was associated with significantly higher mortality (42 and 39% respectively; P = 0.05). In group 1, baseline endotoxin activity was low [0.22 endotoxin activity units (EAU), 0.15-0.43] and did not change significantly during the observation period. In group 2, baseline endotoxin activity was elevated (0.52 EAU (0.39-0.62)) and remained high on day 2, 3, and 4. In group 3, baseline endotoxin activity was elevated (0.56 EAU (0.28-0.80)) and similarly to group 2, remained high on day 2, 3, and 4. The presence of coagulation disorders indicates a high-risk subpopulation of critically ill patients as reflected in significantly higher mortality rates and increased endotoxin activity.

Elevated Serum PCT in Septic Shock With Endotoxemia Is Associated With a Higher Mortality Rate.

To examine the effect of endotoxemia on the procalcitonin (PCT) serum levels and mortality rates of adult patients with septic shock diagnosed on the day of admission to the intensive care unit (ICU).A retrospective observational study was performed over a 2-year period. Levels of PCT were compared for septic shock patients with and without endotoxemia on admission to the ICU. Endotoxemia was identified with an Endotoxin Activity Assay.One hundred fifty-seven patients with septic shock were enrolled into the study. Group 1 consisted of patients with elevated endotoxin activity (EA) (n = 95, EA = 0.57 endotoxin activity unit [EAU] [0.46-0.67]) and Group 2 consisted of patients with low EA (n = 62, EA = 0.27 EAU [0.17-0.36]). Acute Physiology And Chronic Health Evaluation II (APACHE II) score and SOFA score were similar in both groups (APACHE II = 23 [16-29] and 19 [16-25]; Sequential Organ Failure Assessment [SOFA] = 10 [7-13] and 11 [8-12] in Groups 1 and 2, respectively) (nonsignificant). The PCT level was 6 times higher in Group 1 than in Group 2 (19.6 ng/mL vs. 3.1 ng/mL, P < 0.001). There was a strong correlation between EA and serum PCT (P < 0.001, R = 0.5). The presence of endotoxemia on admission to the ICU was associated with an increased mortality rate: 52% in the group of patients with endotoxemia and 25% in the group without endotoxemia. EA in survivors was 0.39 EAU (0.26-0.57) and 0.53 EAU (0.4-0.61) in nonsurvivors (P = 0.004). The median PCT level in survivors was 6.7 ng/mL (2.3-28.0), compared with 16.7 ng/mL (5.3-31.0) in nonsurvivors (P = 0.04).This observational study revealed that endotoxemia in patients with septic shock on admission to the ICU was frequently found and was associated with an elevated PCT level and a high mortality rate. Endotoxemia was a common occurrence in patients with septic shock, regardless of the infecting microorganism.