7 research outputs found
Determination of modulation of inflammatory immune response in Bifidobacterium longum strains isolated from biopsies of children with inflammatory bowel diseases
No full textCharles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Author: Anežka Hlavatá Supervisor: RNDr. Klára Konečná, Ph.D. Consultant: Ing. Tomáš Hudcovic, CSc. Title of diploma: Determination of modulation of inflammatory immune response in Bifidobacterium longum strains isolated from biopsies of children with inflammatory bowel diseases Aim of the study: The aim of this study was to test 20 strains of Bifidobacterium longum isolated from biopsy tissue of young patients with a diagnosis of IBD or suspicion of IBD (aged 4-18 years) and to determine their ability to elicit or modulate immune responses using suitable cell models, such as the human Caco-2 cell line and the HEK293 cell line. Methods: Twenty strains of Bifidobacterium longum ssp. longum were cultured and subsequently heat- inactivated. Their ability to modulate immune responses was assessed using the Caco-2 cell line. An inflammatory response was induced by interleukin-1β, which was added to the Caco-2 cells in both prophylactic and therapeutic setups. Parallel experiments were conducted under non-inflammatory conditions (an immunomodulatory model without interleukin-1β). Control conditions included pure medium and PAM3CSK4 at various concentrations. Furthermore, signaling by these bacterial...Univerzita Karlova Farmaceutická fakulta v Hradci Králové Katedra biologických a lékařských věd Kandidátka: Anežka Hlavatá Školitelka: RNDr. Klára Konečná, Ph.D. Konzultant: Ing. Tomáš Hudcovic, CSc. Název diplomové práce: Stanovení modulace zánětlivé imunitní odpovědi u kmenů Bifidobacterium longum izolovaných z biopsií dětí se zánětlivým střevním onemocněním Cíl práce: Cílem této práce bylo otestovat 20 kmenů Bifidobacterium longum izolovaných z bioptické tkáně mladých pacientů s diagnózou zánětlivého střevního onemocnění nebo podezřením na zánětlivé střevní onemocnění (ve věku 4-18 let) a stanovit jejich schopnost vyvolat nebo modulovat imunitní odpověď na vhodných buněčných modelech, jako je lidská buněčná linie Caco-2 a linie HEK293. Metody: 20 kmenů Bifidobacterium longum ssp. longum bylo kultivováno a následně tepelně inaktivováno. Byla stanovena schopnost těchto kmenů modulovat imunitní odpověď v Caco-2 buněčné linii. Zánětlivá reakce byla vyvolána pomocí interleukinu-1β, který byl ke Caco-2 buňkám přidáván v profylaktickém a terapeutickém nastavení. Souběžně byly provedeny i experimenty v nezánětlivém nastavení (model imunomodulace bez interleukinu-1β). Jako kontrola bylo zařazeno čisté medium a PAM3CSK4 v různých koncentracích. Dále byla ověřována signalizace těchto bakteriálních kmenů s...Katedra biologických a lékařských vědDepartment of Biological and Medical SciencesFarmaceutická fakulta v Hradci KrálovéFaculty of Pharmacy in Hradec Králov
Determination of modulation of inflammatory immune response in Bifidobacterium longum strains isolated from biopsies of children with inflammatory bowel diseases
No full textCharles University Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Author: Anežka Hlavatá Supervisor: RNDr. Klára Konečná, Ph.D. Consultant: Ing. Tomáš Hudcovic, CSc. Title of diploma: Determination of modulation of inflammatory immune response in Bifidobacterium longum strains isolated from biopsies of children with inflammatory bowel diseases Aim of the study: The aim of this study was to test 20 strains of Bifidobacterium longum isolated from biopsy tissue of young patients with a diagnosis of IBD or suspicion of IBD (aged 4-18 years) and to determine their ability to elicit or modulate immune responses using suitable cell models, such as the human Caco-2 cell line and the HEK293 cell line. Methods: Twenty strains of Bifidobacterium longum ssp. longum were cultured and subsequently heat- inactivated. Their ability to modulate immune responses was assessed using the Caco-2 cell line. An inflammatory response was induced by interleukin-1β, which was added to the Caco-2 cells in both prophylactic and therapeutic setups. Parallel experiments were conducted under non-inflammatory conditions (an immunomodulatory model without interleukin-1β). Control conditions included pure medium and PAM3CSK4 at various concentrations. Furthermore, signaling by these bacterial..
The Gut Microbiota Affects Corticosterone Production in the Murine Small Intestine
No full textGlucocorticoids (GCs) are hormones that are released in response to stressors and exhibit many activities, including immunomodulatory and anti-inflammatory activities. They are primarily synthesized in the adrenal gland but are also produced in peripheral tissues via regeneration of adrenal 11-oxo metabolites or by de novo synthesis from cholesterol. The present study investigated the influence of the microbiota on de novo steroidogenesis and regeneration of corticosterone in the intestine of germ-free (GF) and specific pathogen-free mice challenged with a physical stressor (anti-CD3 antibody i.p. injection). In the small intestine, acute immune stress resulted in increased mRNA levels of the proinflammatory cytokines IL1β, IL6 and Tnfα and genes involved in de novo steroidogenesis (Stard3 and Cyp11a1), as well as in regeneration of active GCs from their 11-oxo metabolites (Hsd11b1). GF mice showed a generally reduced transcriptional response to immune stress, which was accompanied by decreased intestinal corticosterone production and reduced expression of the GC-sensitive marker Fkbp5. In contrast, the interaction between stress and the microbiota was not detected at the level of plasma corticosterone or the transcriptional response of adrenal steroidogenic enzymes. The results indicate a differential immune stress-induced intestinal response to proinflammatory stimuli and local corticosterone production driven by the gut microbiota
Immunomodulation by diet : individual differences in sensitivity in layer hens
No full textEnhancing relevant immunity of production animals to achieve more robust animals is receiving more and more attention. Several epidemics have hit production animals recently and with devastating consequences, but enhancing diseases resistance increasingly provides new opportunities. Furthermore, welfare and health of production animals is becoming a more and more consumer driven topic. Several routes are being used to approach the possibility of enhancing immunity such as selective breeding, enriched and altered housing conditions, vaccination programs, diet supplementation with immune stimulating components, and other management procedures. Disease susceptibility has been shown to be related to stress reactivity, which in turn is related to differences in HPA axis reactivity. Interestingly, independent of selection criteria used, the extremes of various selection procedures result in a recurrent dichotomy in HPA axis reactivity, either being hyperresponsive or hyporesponsive to stress. Animals with a hyperresponsive HPA axis show greater environmental sensitivity, while the hyporeactive animals are more intrinsically regulated. Often, research on immunomodulation is performed with compromised animals and/or exaggerated supplementation of dietary components in one generation of animals, but epigenetics by definition seems to be the mechanism for mothers to prepare their offspring for the environment they will be born into. Enhancing immunity through normal diet in uncompromised animals is rarely investigated, let alone over generations. In this thesis the aim was to induce immunomodulation through diet in selection lines of chicken that have previously been selected on their antibody response to sheep red blood cells over two generations of chicken. First, potential HPA axis differences were examined in these selection lines to establish their environmental sensitivity, whereafter immunomodulation through normal diet was investigated in humoral and cellular parameters of immunity. As humoral immunocompentence was not easily modulated, an immune trigger was used to detect potential differences in humoral reactivity. The selection lines showed differential sensitivity to immunomodulation by diet in both generations, suggesting that adaptation to environmental factors may be a line-specific (genetically based) process, with differential neuroendocrine regulation. Most interestingly, the second generation showed effects of the diets in all the selection lines, albeit in different manners. It is concluded that normal diet can cause immunomodulation, mainly in animals with hyper HPA axis reactivity, and that introducing such practices may be more beneficial when mothers are treated, as all offspring showed immunomodulation, irrespective of selection line. While genetic background and/or epigenetic processes on neuroendocrine and immune regulation of the individual form the framework wherein individual immunomodulation by diet can take place, environmental conditions determine if the modulation is beneficial or not. <br/
Unique Gene Expression Signatures in the Intestinal Mucosa and Organoids Derived from Germ-Free and Monoassociated Mice
No full textCommensal microbiota contribute to gut homeostasis by inducing transcription of mucosal genes. Analysis of the impact of various microbiota on intestinal tissue provides an important insight into the function of this organ. We used cDNA microarrays to determine the gene expression signature of mucosa isolated from the small intestine and colon of germ-free (GF) mice and animals monoassociated with two E. coli strains. The results were compared to the expression data obtained in conventionally reared (CR) mice. In addition, we analyzed gene expression in colon organoids derived from CR, GF, and monoassociated animals. The analysis revealed that the complete absence of intestinal microbiota mainly affected the mucosal immune system, which was not restored upon monoassociation. The most important expression changes observed in the colon mucosa indicated alterations in adipose tissue and lipid metabolism. In the comparison of differentially expressed genes in the mucosa or organoids obtained from GF and CR mice, only six genes were common for both types of samples. The results show that the increased expression of the angiopoietin-like 4 (Angptl4) gene encoding a secreted regulator of lipid metabolism indicates the GF status
Health and disease status of Australia's most critically endangered mammal the Gilbert's potoroo (Potorous gilbertii)
No full textThe Gilbert's potoroo (Potorous gilbertii) is a small marsupial endemic to the Two Peoples Bay Nature Reserve in the south-west of Western Australia. The Gilbert's potoroo is classified as Australia's most critically endangered mammal (IUCN 2006) with an estimated population of only 35 individuals. This thesis examines the health and disease status of the Gilbert's potoroo, presenting a strong case for the relatively new concept of disease as a potential threatening factor and modifier of population decline.
Specific diseases, including Cryptococcus, ectoparasitism, endoparasitism, haemoparasitism, Toxoplasma and a novel Treponema organism are extensively studied. An assessment of the clinical significance of these diseases is made, and management strategies are recommended to minimise the impact of these diseases on both the wild and captive population.
The novel Treponema organism which clinically presents with tenacious, green discharge and an associated balanoposthitis in males is molecularly characterized. Epidemiological studies show the effects of this agent on reproductive function and a penicillin-based treatment regime is trialled in the analogous long-nosed potoroo (Potorous tridactylus) with a recommendation to then trial this treatment regime in the critically endangered Gilbert's potoroo.
Standard haematological and urinalysis findings are tabulated to form reference ranges for this species. A treatment regime for Cryptococcus in the analogous long-nosed potoroo is reported and parasitological findings, including the identification of a novel tick species are discussed.
This thesis addresses key health issues, which have subsequently been incorporated into the Recovery Plan of the Gilbert's potoroo. A document encompassing multiple disciplines and expertise to support the recovery of this critically endangered marsupial in its current environment. In addition, this thesis outlines a recommended health monitoring and treatment protocol for future translocation procedures and provides a working example of the emerging importance of health monitoring in threatened species recovery programs
Sotagliflozin in patients with diabetes and recent worsening heart failure
No full textBACKGROUND Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of hospitalization for heart failure or death from cardiovascular causes among patients with stable heart failure. However, the safety and efficacy of SGLT2 inhibitors when initiated soon after an episode of decompensated heart failure are unknown. METHODS We performed a multicenter, double-blind trial in which patients with type 2 diabetes mellitus who were recently hospitalized for worsening heart failure were randomly assigned to receive sotagliflozin or placebo. The primary end point was the total number of deaths from cardiovascular causes and hospitalizations and urgent visits for heart failure (first and subsequent events). The trial ended early because of loss of funding from the sponsor. RESULTS A total of 1222 patients underwent randomization (608 to the sotagliflozin group and 614 to the placebo group) and were followed for a median of 9.0 months; the first dose of sotagliflozin or placebo was administered before discharge in 48.8% and a median of 2 days after discharge in 51.2%. Among these patients, 600 primary end-point events occurred (245 in the sotagliflozin group and 355 in the placebo group). The rate (the number of events per 100 patient-years) of primary end-point events was lower in the sotagliflozin group than in the placebo group (51.0 vs. 76.3; hazard ratio, 0.67; 95% confidence interval [CI], 0.52 to 0.85; P<0.001). The rate of death from cardiovascular causes was 10.6 in the sotagliflozin group and 12.5 in the placebo group (hazard ratio, 0.84; 95% CI, 0.58 to 1.22); the rate of death from any cause was 13.5 in the sotagliflozin group and 16.3 in the placebo group (hazard ratio, 0.82; 95% CI, 0.59 to 1.14). Diarrhea was more common with sotagliflozin than with placebo (6.1% vs. 3.4%), as was severe hypoglycemia (1.5% vs. 0.3%). The percentage of patients with hypotension was similar in the sotagliflozin group and the placebo group (6.0% and 4.6%, respectively), as was the percentage with acute kidney injury (4.1% and 4.4%, respectively). The benefits of sotagliflozin were consistent in the prespecified subgroups of patients stratified according to the timing of the first dose. CONCLUSIONS In patients with diabetes and recent worsening heart failure, sotagliflozin therapy, initiated before or shortly after discharge, resulted in a significantly lower total number of deaths from cardiovascular causes and hospitalizations and urgent visits for heart failure than placebo. (Funded by Sanofi and Lexicon Pharmaceuticals; SOLOIST-WHF ClinicalTrials.gov number, NCT03521934.)
