TY - THES A1 - Ganesh, Bhanu Priya T1 - Host-microbe interactions in the inflamed gut T1 - Wirt-Mikroben-Interaktionen im entzündenden Darm N2 - Initiation and perpetuation of inflammatory bowel diseases (IBD) may result from an exaggerated mucosal immune response to the luminal microbiota in a susceptible host. We proposed that this may be caused either 1) by an abnormal microbial composition or 2) by weakening of the protective mucus layer due to excessive mucus degradation, which may lead to an easy access of luminal antigens to the host mucosa triggering inflammation. We tested whether the probiotic Enterococcus faecium NCIMB 10415 (NCIMB) is capable of reducing chronic gut inflammation by changing the existing gut microbiota composition and aimed to identify mechanisms that are involved in possible beneficial effects of the probiotic. To identify health-promoting mechanisms of the strain, we used interleukin (IL)-10 deficient mice that spontaneously develop gut inflammation and fed these mice a diet containing NCIMB (106 cells g-1) for 3, 8 and 24 weeks, respectively. Control mice were fed an identically composed diet but without the probiotic strain. No clear-cut differences between the animals were observed in pro-inflammatory cytokine gene expression and in intestinal microbiota composition after probiotic supplementation. However, we observed a low abundance of the mucin-degrading bacterium Akkermansia muciniphila in the mice that were fed NCIMB for 8 weeks. These low cell numbers were associated with significantly lower interferon gamma (IFN-γ) and IFN-γ-inducible protein (IP-10) mRNA levels as compared to the NCIMB-treated mice that were killed after 3 and 24 weeks of intervention. In conclusion, NCIMB was not capable of reducing gut inflammation in the IL-10-/- mouse model. To further identify the exact role of A. muciniphila and uncover a possible interaction between this bacterium, NCIMB and the host in relation to inflammation, we performed in vitro studies using HT-29 colon cancer cells. The HT-29 cells were treated with bacterial conditioned media obtained by growing either A. muciniphila (AM-CM) or NCIMB (NCIMB-CM) or both together (COMB-CM) in Dulbecco’s Modified Eagle Medium (DMEM) for 2 h at 37 °C followed by bacterial cell removal. HT-29 cells treated with COMB-CM displayed reduced cell viability after 18 h (p<0.01) and no viable cells were detected after 24 h of treatment, in contrast to the other groups or heated COMB-CM. Detection of activated caspase-3 in COMB-CM treated groups indicated that death of the HT-29 cells was brought about by apoptosis. It was concluded that either NCIMB or A. muciniphila produce a soluble and heat-sensitive factor during their concomitant presence that influences cell viability in an in vitro system. We currently hypothesize that this factor is a protein, which has not yet been identified. Based on the potential effect of A. muciniphila on inflammation (in vivo) and cell-viability (in vitro) in the presence of NCIMB, we investigated how the presence of A. muciniphila affects the severity of an intestinal Salmonella enterica Typhimurium (STm)-induced gut inflammation using gnotobiotic C3H mice with a background microbiota of eight bacterial species (SIHUMI, referred to as simplified human intestinal microbiota). Presence of A. muciniphila in STm-infected SIHUMI (SIHUMI-AS) mice caused significantly increased histopathology scores and elevated mRNA levels of IFN-γ, IP-10, tumor necrosis factor alpha (TNF-α), IL-12, IL-17 and IL-6 in cecal and colonic tissue. The number of mucin filled goblet cells was 2- to 3- fold lower in cecal tissue of SIHUMI-AS mice compared to SIHUMI mice associated with STm (SIHUMI-S) or A. muciniphila (SIHUMI-A) or SIHUMI mice. Reduced goblet cell numbers significantly correlated with increased IFN-γ (r2 = -0.86, ***P<0.001) in all infected mice. In addition, loss of cecal mucin sulphation was observed in SIHUMI-AS mice. Concomitant presence of A. muciniphila and STm resulted in a drastic change in microbiota composition of the SIHUMI consortium. The proportion of Bacteroides thetaiotaomicron in SIHUMI, SIHUMI-A and SIHUMI-S mice made up to 80-90% but was completely taken over by STm in SIHUMI-AS mice contributing 94% to total bacteria. These results suggest that A. muciniphila exacerbates STm-induced intestinal inflammation by its ability to disturb host mucus homeostasis. In conclusion, abnormal microbiota composition together with excessive mucus degradation contributes to severe intestinal inflammation in a susceptible host. N2 - Die Initiation and die Manifestation von entzündlichen Darmerkrankungen (inflammatory bowel diseases - IBD) können aus einer übersteigerten mukosalen Immunreaktion auf die luminale Mikrobiota in einem empfänglichen Wirt resultieren. Wir schlagen vor, dass dies entweder durch 1) eine abnormale mikrobielle Zusammensetzung oder 2) die Abschwächung der schützenden Schleimschicht, eingeleitet durch deren fortgeschrittenen Abbau, verursacht werden kann. Diese Entwicklung ermöglicht einen erleichterten Zugang des luminalen Antigens zu der Mukosa des Wirts und somit die Auslösung der Entzündung. Wir haben getestet, ob das probiotische Bakterium Enterococcus faecium NCIMB 10415 (NCIMB) in der Lage ist, der chronischen Darmentzündung durch Veränderung der Zusammensetzung der Darmmikrobiota entgegenzuwirken und strebten an, die zugrunde liegenden Mechanismen der probiotischen Wirkungsweise zu identifizieren. Für die Aufklärung der gesundheitsfördernden Mechanismen dieses Bakterienstammes wurden Interleukin-10 defiziente Mäuse verwendet, die spontan eine Darmentzündung entwickeln. Den Mäusen wurde für 3, 8 und 24 Wochen eine NCIMB enthaltende Diät verabreicht. Nach der Fütterung waren keine eindeutigen Unterschiede zwischen den Gruppen hinsichtlich der Genexpression von pro-inflammatorischen Zytokinen und der Zusammensetzung der Darmmikrobiota zu beobachten, obwohl eine geringere Zellzahl des schleimabbauenden Bakteriums Akkermansia muciniphila in den mit NCIMB gefütterten Mäusen nach 8 Wochen festgestellt wurde. Daraus folgt, dass NCIMB nicht in der Lage ist, dem Verlauf der Darmentzündung im IL-10-/--Mausmodell entgegenzuwirken. In der nachfolgenden Studie wurde untersucht, wie die Anwesenheit von A. muciniphila den Ausprägungsgrad einer intestinalen Salmonella enterica Typhimurium (STm) induzierten Darmentzündung beeinflusst. Dafür wurden gnobiotische C3H-Mäuse mit einem mikrobiellen Hintergrund von acht Bakterienspezies (SIHUMI) verwendet. Die gleichzeitige Anwesenheit von A. muciniphila und STm verursachte eine drastische Veränderung der Mikrobiota-Zusammensetzung des SIHUMI-Konsortiums. Diese Ergebnisse zeigen, dass A. muciniphila durch seine Fähigkeit, die Homöostase/Selbstregulation der Schleimbildung zu stören, die STm-induzierte Darmentzündung verschärft. Es kann geschlußfolgert werden, dass eine abweichende Zusammensetzung der Mikrobiota in Kombination mit einem massiven Abbau des Mucus zur schweren intestinalen Entzündung im empfänglichen Wirt beiträgt. KW - IBD KW - probiotics KW - immune response KW - mucus KW - goblet cells KW - chronic and acute inflammation KW - apoptosis KW - commensal KW - cytokines KW - pathogen KW - infection Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-69558 ER - TY - GEN A1 - Haß, Ulrike A1 - Herpich, Catrin A1 - Norman, Kristina T1 - Anti-Inflammatory Diets and Fatigue T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Accumulating data indicates a link between a pro-inflammatory status and occurrence of chronic disease-related fatigue. The questions are whether the observed inflammatory profile can be (a) improved by anti-inflammatory diets, and (b) if this improvement can in turn be translated into a significant fatigue reduction. The aim of this narrative review was to investigate the effect of anti-inflammatory nutrients, foods, and diets on inflammatory markers and fatigue in various patient populations. Next to observational and epidemiological studies, a total of 21 human trials have been evaluated in this work. Current available research is indicative, rather than evident, regarding the effectiveness of individuals’ use of single nutrients with anti-inflammatory and fatigue-reducing effects. In contrast, clinical studies demonstrate that a balanced diet with whole grains high in fibers, polyphenol-rich vegetables, and omega-3 fatty acid-rich foods might be able to improve disease-related fatigue symptoms. Nonetheless, further research is needed to clarify conflicting results in the literature and substantiate the promising results from human trials on fatigue. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 803 KW - chronic fatigue KW - cancer KW - fatigue reduction diet KW - probiotics KW - polyphenols KW - omega-3 fatty acids KW - anti-inflammatory nutrition KW - cytokines KW - inflammation KW - myalgic encephalomyelitis Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-441172 SN - 1866-8372 IS - 803 ER - TY - GEN A1 - Zwaag, Jelle A1 - Horst, Rob ter A1 - Blaženović, Ivana A1 - Stößel, Daniel A1 - Ratter, Jacqueline A1 - Worseck, Josephine M. A1 - Schauer, Nicolas A1 - Stienstra, Rinke A1 - Netea, Mihai G. A1 - Jahn, Dieter A1 - Pickkers, Peter A1 - Kox, Matthijs T1 - Involvement of lactate and pyruvate in the anti-inflammatory effects exerted by voluntary activation of the sympathetic nervous system T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - We recently demonstrated that the sympathetic nervous system can be voluntarily activated following a training program consisting of cold exposure, breathing exercises, and meditation. This resulted in profound attenuation of the systemic inflammatory response elicited by lipopolysaccharide (LPS) administration. Herein, we assessed whether this training program affects the plasma metabolome and if these changes are linked to the immunomodulatory effects observed. A total of 224 metabolites were identified in plasma obtained from 24 healthy male volunteers at six timepoints, of which 98 were significantly altered following LPS administration. Effects of the training program were most prominent shortly after initiation of the acquired breathing exercises but prior to LPS administration, and point towards increased activation of the Cori cycle. Elevated concentrations of lactate and pyruvate in trained individuals correlated with enhanced levels of anti-inflammatory interleukin (IL)-10. In vitro validation experiments revealed that co-incubation with lactate and pyruvate enhances IL-10 production and attenuates the release of pro-inflammatory IL-1 beta and IL-6 by LPS-stimulated leukocytes. Our results demonstrate that practicing the breathing exercises acquired during the training program results in increased activity of the Cori cycle. Furthermore, this work uncovers an important role of lactate and pyruvate in the anti-inflammatory phenotype observed in trained subjects. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1413 KW - metabolomics KW - LPS KW - endotoxin KW - pyruvate KW - lactate KW - cytokines KW - inflammation KW - human endotoxemia KW - cori cycle KW - warburg effect Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-517784 SN - 1866-8372 IS - 4 ER - TY - GEN A1 - Kessler, Katharina A1 - Hornemann, Silke A1 - Rudovich, Natalia A1 - Weber, Daniela A1 - Grune, Tilman A1 - Kramer, Achim A1 - Pfeiffer, Andreas F. H. A1 - Pivovarova-Ramich, Olga T1 - Saliva samples as a tool to study the effect of meal timing on metabolic and inflammatory biomarkers T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Meal timing affects metabolic regulation in humans. Most studies use blood samples fortheir investigations. Saliva, although easily available and non-invasive, seems to be rarely used forchrononutritional studies. In this pilot study, we tested if saliva samples could be used to studythe effect of timing of carbohydrate and fat intake on metabolic rhythms. In this cross-over trial, 29 nonobese men were randomized to two isocaloric 4-week diets: (1) carbohydrate-rich meals until13:30 and high-fat meals between 16:30 and 22:00 or (2) the inverse order of meals. Stimulated salivasamples were collected every 4 h for 24 h at the end of each intervention, and levels of hormones andinflammatory biomarkers were assessed in saliva and blood. Cortisol, melatonin, resistin, adiponectin, interleukin-6 and MCP-1 demonstrated distinct diurnal variations, mirroring daytime reports inblood and showing significant correlations with blood levels. The rhythm patterns were similar forboth diets, indicating that timing of carbohydrate and fat intake has a minimal effect on metabolicand inflammatory biomarkers in saliva. Our study revealed that saliva is a promising tool for thenon-invasive assessment of metabolic rhythms in chrononutritional studies, but standardisation of sample collection is needed in out-of-lab studies. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1425 KW - meal timing KW - saliva KW - circadian clock KW - adiponectin KW - resistin KW - visfatin KW - insulin KW - melatonin KW - cortisol KW - cytokines Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-512079 SN - 1866-8372 IS - 2 ER - TY - THES A1 - Klauder, Julia T1 - Makrophagenaktivierung durch Hyperinsulinämie als Auslöser eines Teufelkreises der Entzündung im Kontext des metabolischen Syndroms T1 - Macrophage activation by hyperinsulinemia as a trigger of a vicious cycle of inflammation in the context of the metabolic syndrome N2 - Insulinresistenz ist ein zentraler Bestandteil des metabolischen Syndroms und trägt maßgeblich zur Ausbildung eines Typ-2-Diabetes bei. Eine mögliche Ursache für die Entstehung von Insulinresistenz ist eine chronische unterschwellige Entzündung, welche ihren Ursprung im Fettgewebe übergewichtiger Personen hat. Eingewanderte Makrophagen produzieren vermehrt pro-inflammatorische Mediatoren, wie Zytokine und Prostaglandine, wodurch die Konzentrationen dieser Substanzen sowohl lokal als auch systemisch erhöht sind. Darüber hinaus weisen übergewichtige Personen einen gestörten Fettsäuremetabolismus und eine erhöhte Darmpermeabilität auf. Ein gesteigerter Flux an freien Fettsäuren vom Fettgewebe in andere Organe führt zu einer lokalen Konzentrationssteigerung in diesen Organen. Eine erhöhte Darmpermeabilität erleichtert das Eindringen von Pathogenen und anderer körperfremder Substanzen in den Körper. Ziel dieser Arbeit war es, zu untersuchen, ob hohe Konzentrationen von Insulin, des bakteriellen Bestandteils Lipopolysaccharid (LPS) oder der freien Fettsäure Palmitat eine Entzündungsreaktion in Makrophagen auslösen oder verstärken können und ob diese Entzündungsantwort zur Ausbildung einer Insulinresistenz beitragen kann. Weiterhin sollte untersucht werden, ob Metabolite und Signalsubstanzen, deren Konzentrationen beim metabolischen Syndrom erhöht sind, die Produktion des Prostaglandins (PG) E2 begünstigen können und ob dieses wiederum die Entzündungsreaktion und seine eigene Produktion in Makrophagen regulieren kann. Um den Einfluss dieser Faktoren auf die Produktion pro-inflammatorischer Mediatoren in Makrophagen zu untersuchen, wurden Monozyten-artigen Zelllinien und primäre humane Monozyten, welche aus dem Blut gesunder Probanden isoliert wurden, in Makrophagen differenziert und mit Insulin, LPS, Palmitat und/ oder PGE2 inkubiert. Überdies wurden primäre Hepatozyten der Ratte isoliert und mit Überständen Insulin-stimulierter Makrophagen inkubiert, um zu untersuchen, ob die Entzündungsanwort in Makrophagen an der Ausbildung einer Insulinresistenz in Hepatozyten beteiligt ist. Insulin induzierte die Expression pro-inflammatorischer Zytokine in Makrophagen-artigen Zelllinien wahrscheinlich vorrangig über den Phosphoinositid-3-Kinase (PI3K)-Akt-Signalweg mit anschließender Aktiverung des Transkriptionsfaktors NF-κB (nuclear factor 'kappa-light-chain-enhancer' of activated B-cells). Die dabei ausgeschütteten Zytokine hemmten in primären Hepatozyten der Ratte die Insulin-induzierte Expression der Glukokinase durch Überstände Insulin-stimulierter Makrophagen. Auch LPS oder Palmitat, deren lokale Konzentrationen im Zuge des metabolischen Syndroms erhöht sind, waren in der Lage, die Expression pro-inflammatorischer Zytokine in Makrophagen-artigen Zelllinien zu stimulieren. Während LPS seine Wirkung, laut Literatur, unbestritten über eine Aktivierung des Toll-ähnlichen Rezeptors (toll-like receptor; TLR) 4 vermittelt, scheint Palmitat jedoch weitestgehend TLR4-unabhängig wirken zu können. Vielmehr schien die de novo-Ceramidsynthese eine entscheidene Rolle zu spielen. Darüber hinaus verstärkte Insulin sowohl die LPS- als auch die Palmitat-induzierte Ent-zündungsantwort in beiden Zelllinien. Die in Zelllinien gewonnenen Ergebnisse wurden größtenteils in primären humanen Makrophagen bestätigt. Desweiteren induzierten sowohl Insulin als auch LPS oder Palmitat die Produktion von PGE2 in den untersuchten Makrophagen. Die Daten legen nahe, dass dies auf eine gesteigerte Expression PGE2-synthetisierender Enzyme zurückzuführen ist. PGE2 wiederum hemmte auf der einen Seite die Stimulus-abhängige Expression des pro-inflammatorischen Zytokins Tumornekrosefaktor (TNF) α in U937-Makrophagen. Auf der anderen Seite verstärkte es jedoch die Expression der pro-inflammatorischen Zytokine Interleukin- (IL-) 1β und IL-8. Darüber hinaus verstärkte es die Expression von IL-6-Typ-Zytokinen, welche sowohl pro- als auch anti-inflammatorisch wirken können. Außerdem vestärkte PGE2 die Expression PGE2-synthetisierender Enzyme. Es scheint daher in der Lage zu sein, seine eigene Synthese zu verstärken. Zusammenfassend kann die Freisetzung pro-inflammatorischer Mediatoren aus Makro-phagen im Zuge einer Hyperinsulinämie die Entstehung einer Insulinresistenz begünstigen. Insulin ist daher in der Lage, einen Teufelskreis der immer stärker werdenden Insulin-resistenz in Gang zu setzen. Auch Metabolite und Signalsubstanzen, deren Konzentrationen beim metabolischen Syndrom erhöht sind (zum Beispiel LPS, freie Fettsäuren und PGE2), lösten Entzündungsantworten in Makrophagen aus. Das wechselseitige Zusammenspiel von Insulin und diesen Metaboliten und Signalsubstanzen löste eine stärkere Entzündungsantwort in Makrophagen aus als jeder der Einzelkomponenten. Die dadurch freigesetzten Zytokine könnten zur Manifestation einer Insulinresistenz und des metabolischen Syndroms beitragen. N2 - Insulin resistance is a central component of the metabolic syndrome and is a major contributor to the development of type 2 diabetes. One possible cause of insulin resistance is chronic low-grade inflammation, which originates in the adipose tissue of obese individuals. Immigrated macrophages produce increased levels of pro-inflammatory mediators such as cytokines and prostaglandins, resulting in increased concentrations of these substances both locally and systemically. In addition, obese individuals exhibit impaired fatty acid metabolism and increased intestinal permeability. Increased flux of free fatty acids from adipose tissue to other organs results in increased local concentrations in these organs. Increased intestinal permeability facilitates the entry of pathogens and other exogenous substances into the body. The aim of this work was to investigate whether high concentrations of insulin, the bacterial component lipopolysaccharide (LPS), or the free fatty acid palmitate can induce or enhance an inflammatory response in macrophages and whether this inflammatory response can contribute to the development of insulin resistance. Furthermore, to investigate whether metabolites and signaling substances whose concentrations are elevated in the metabolic syndrome can promote the production of prostaglandin (PG) E2 and whether this in turn can regulate the inflammatory response and its own production in macrophages. To investigate the influence of these factors on the production of pro-inflammatory mediators in macrophages, monocyte-like cell lines and primary human monocytes, that were isolated from the blood of healthy volunteers, were differentiated into macrophages and incubated for with insulin, LPS, palmitate and/ or PGE2. In addition, primary rat hepatocytes were isolated and incubated with supernatants of insulin-stimulated macrophages to investigate whether the inflammatory response in macrophages is involved in the development of insulin resistance in hepatocytes. Insulin induced the expression of pro-inflammatory cytokines in macrophage-like cell lines probably primarily via the phosphoinositide 3-kinase (PI3K)-Akt pathway with subsequent activation of the transcription factor NF-κB (nuclear factor 'kappa-light-chain-enhancer' of activated B-cells). The cytokines released in this process inhibited insulin-induced expression of glucokinase by supernatants of insulin-stimulated macrophages in primary rat hepatocytes. Also, LPS or palmitate, whose local concentrations are increased in the course of metabolic syndrome, were able to stimulate the expression of pro-inflammatory cytokines in macrophage-like cell lines. While LPS, according to the literature, undisputedly mediates its effect via activation of toll-like receptor (TLR) 4, palmitate, however, appears to be able to act mainly in a TLR4-independent manner. Rather, de novo ceramide synthesis appeared to play a crucial role. Moreover, insulin enhanced both LPS- and palmitate-induced inflammatory responses in both cell lines. The results obtained in macrophage-like cell lines were largely confirmed in primary human macrophages. Furthermore, both insulin and LPS or palmitate induced PGE2 production in the macrophages studied. The data suggest that this was not due to increased expression of arachidonic acid-synthesizing enzymes but rather to increased expression of PGE2-synthesizing enzymes. On the one hand PGE2 inhibited the stimulus-dependent expression of the pro-inflammatory cytokine tumor necrosis factor (TNF) α in U937 macrophages. However, on the other hand, it enhanced the expression of the pro-inflammatory cytokines interleukin- (IL-) 1β and IL-8. In addition, it enhanced the expression of IL-6-type cytokines, which can be both pro- and anti-inflammatory. In addition, PGE2 enhanced the expression of PGE2-synthesizing enzymes. It therefore appears to be able to enhance its own synthesis. In conclusion, the release of pro-inflammatory mediators from macrophages in the course of hyperinsulinemia may favor the development of insulin resistance. Thus, the hyperinsulinemia might be augmented in a vicious cycle feed forward loop. Metabolites and signaling substances whose concentrations are elevated in the metabolic syndrome (for example, LPS, free fatty acids, and PGE2) also triggered inflammatory responses in macrophages. The synergistic interaction of insulin and these metabolites and signaling substances triggered a stronger inflammatory response in macrophages than any of the individual components. The released cytokines could contribute to the manifestation of insulin resistance and the metabolic syndrome. KW - Metabolisches Syndrom KW - Entzündung KW - Makrophagen KW - Insulin KW - Zytokine KW - Typ-2-Diabetes KW - Prostaglandin KW - inflammation KW - insulin KW - macrophages KW - metabolic syndrom KW - prostaglandine KW - Type-2-diabetes KW - cytokines Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-520199 ER -