TY - GEN A1 - Hocher, Berthold A1 - Reichetzeder, Christoph A1 - Dwi Putra, Sulistyo Emantoko A1 - Slowinski, Torsten A1 - Neuber, Corinna A1 - Kleuser, Burkhard A1 - Pfab, Thiemo T1 - Increased global placental DNA methylation levels are associated with gestational diabetes N2 - Background: Gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes. It is known that GDM is associated with an altered placental function and changes in placental gene regulation. More recent studies demonstrated an involvement of epigenetic mechanisms. So far, the focus regarding placental epigenetic changes in GDM was set on gene-specific DNA methylation analyses. Studies that robustly investigated placental global DNA methylation are lacking. However, several studies showed that tissue-specific alterations in global DNA methylation are independently associated with type 2 diabetes. Thus, the aim of this study was to characterize global placental DNA methylation by robustly measuring placental DNA 5-methylcytosine (5mC) content and to examine whether differences in placental global DNA methylation are associated with GDM. Methods: Global DNA methylation was quantified by the current gold standard method, LC-MS/MS. In total, 1030 placental samples were analyzed in this single-center birth cohort study. Results: Mothers with GDM displayed a significantly increased global placental DNA methylation (3.22 ± 0.63 vs. 3.00 ± 0.46 %; p = 0.013; ±SD). Bivariate logistic regression showed a highly significant positive correlation between global placental DNA methylation and the presence of GDM (p = 0.0009). Quintile stratification according to placental DNA 5mC levels revealed that the frequency of GDM was evenly distributed in quintiles 1–4 (2.9–5.3 %), whereas the frequency in the fifth quintile was significantly higher (10.7 %; p = 0.003). Bivariate logistic models adjusted for maternal age, BMI, ethnicity, recurrent miscarriages, and familiar diabetes predisposition clearly demonstrated an independent association between global placental DNA hypermethylation and GDM. Furthermore, an ANCOVA model considering known predictors of DNA methylation substantiated an independent association between GDM and placental DNA methylation. Conclusions: This is the first study that employed a robust quantitative assessment of placental global DNA methylation in over a thousand placental samples. The study provides large scale evidence that placental global DNA hypermethylation is associated with GDM, independent of established risk factors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 370 KW - Placenta KW - Gestational diabetes KW - Insulin resistance KW - LC-MS/MS KW - Global DNA methylation KW - Epigenetics KW - Hypermethylation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400914 ER - TY - GEN A1 - Camargo, Rodolfo Gonzalez A1 - Riccardi, Daniela Mendes dos Reis A1 - Ribeiro, Henrique Quintas Teixeira A1 - Carnevali Junior, Luiz Carlos A1 - Matos-Neto, Emidio Marques de A1 - Enjiu, Lucas A1 - Neves, Rodrigo Xavier A1 - Lima, Joanna Darck Carola Correia A1 - Figuerêdo, Raquel Galvão A1 - Alcântara, Paulo Sérgio Martins de A1 - Maximiano, Linda A1 - Otoch, José A1 - Batista Jr., Miguel Luiz A1 - Püschel, Gerhard Paul A1 - Seelaender, Marilia T1 - NF-kappa Bp65 and expression of its pro-inflammatory target genes are upregulated in the subcutaneous adipose tissue of cachectic cancer patients N2 - Cancer cachexia, of which the most notable symptom is severe and rapid weight loss, is present in the majority of patients with advanced cancer. Inflammatory mediators play an important role in the development of cachexia, envisaged as a chronic inflammatory syndrome. The white adipose tissue (WAT) is one of the first compartments affected in cancer cachexia and suffers a high rate of lipolysis. It secretes several cytokines capable of directly regulating intermediate metabolism. A common pathway in the regulation of the expression of pro-inflammatory cytokines in WAT is the activation of the nuclear transcription factor kappa-B (NF-κB). We have examined the gene expression of the subunits NF-κBp65 and NF-κBp50, as well as NF-κBp65 and NF-κBp50 binding, the gene expression of pro-inflammatory mediators under NF-κB control (IL-1β, IL-6, INF-γ, TNF-α, MCP-1), and its inhibitory protein, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκB-α). The observational study involved 35 patients (control group, n = 12 and cancer group, n = 23, further divided into cachectic and non-cachectic). NF-κBp65 and its target genes expression (TNF-α, IL-1β, MCP-1 and IκB-α) were significantly higher in cachectic cancer patients. Moreover, NF-κBp65 gene expression correlated positively with the expression of its target genes. The results strongly suggest that the NF-κB pathway plays a role in the promotion of WAT inflammation during cachexia. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 349 KW - cancer cachexia KW - inflammation KW - white adipose tissue KW - NF-κB KW - IκB Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400163 ER - TY - GEN A1 - Henze, Andrea A1 - Raila, Jens A1 - Kempf, Caroline A1 - Reinke, Petra A1 - Sefrin, Anett A1 - Querfeld, Uwe A1 - Schweigert, Florian J. T1 - Vitamin A metabolism is changed in donors after living-kidney transplantation BT - an observational study N2 - Background The kidneys are essential for the metabolism of vitamin A (retinol) and its transport proteins retinol-binding protein 4 (RBP4) and transthyretin. Little is known about changes in serum concentration after living donor kidney transplantation (LDKT) as a consequence of unilateral nephrectomy; although an association of these parameters with the risk of cardiovascular diseases and insulin resistance has been suggested. Therefore we analyzed the concentration of retinol, RBP4, apoRBP4 and transthyretin in serum of 20 living-kidney donors and respective recipients at baseline as well as 6 weeks and 6 months after LDKT. Results As a consequence of LDKT, the kidney function of recipients was improved while the kidney function of donors was moderately reduced within 6 weeks after LDKT. With regard to vitamin A metabolism, the recipients revealed higher levels of retinol, RBP4, transthyretin and apoRBP4 before LDKT in comparison to donors. After LDKT, the levels of all four parameters decreased in serum of the recipients, while retinol, RBP4 as well as apoRBP4 serum levels of donors increased and remained increased during the follow-up period of 6 months. Conclusion LDKT is generally regarded as beneficial for allograft recipients and not particularly detrimental for the donors. However, it could be demonstrated in this study that a moderate reduction of kidney function by unilateral nephrectomy, resulted in an imbalance of components of vitamin A metabolism with a significant increase of retinol and RBP4 and apoRBP4 concentration in serum of donors. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 373 KW - Donors KW - glomerular filtration rate KW - kidney transplantation KW - retinol KW - retinol-binding protein 4 KW - transthyretin Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400942 ER - TY - GEN A1 - Hocher, Berthold A1 - Oberthür, Dominik A1 - Slowinski, Torsten A1 - Querfeld, Uwe A1 - Schaefer, Franz A1 - Doyon, Anke A1 - Tepel, Martin A1 - Roth, Heinz J. A1 - Grön, Hans J. A1 - Reichetzeder, Christoph A1 - Betzel, Christian A1 - Armbruster, Franz Paul T1 - Modeling of oxidized PTH (oxPTH) and non-oxidized PTH (n-oxPTH) receptor binding and relationship of oxidized to non-oxidized PTH in children with chronic renal failure, adult patients on hemodialysis and kidney transplant recipients N2 - Background: The biological properties of oxidized and non-oxidized PTH are substantially different. Oxidized PTH (oxPTH) loses its PTH receptor-stimulating properties, whereas non-oxidized PTH (n-oxPTH) is a full agonist of the receptor. This was described in more than 20 well published studies in the 1970(s) and 80(s). However, PTH oxidation has been ignored during the development of PTH assays for clinical use so far. Even the nowadays used third generation assay systems do not consider oxidation of PTH. We recently developed an assay to differentiate between oxPTH and n-oxPTH. In the current study we established normal values for this assay system. Furthermore, we compare the ratio of oxPTH to n-oxPTH in different population with chronic renal failure: 620 children with renal failure stage 2-4 of the 4C study, 342 adult patients on dialysis, and 602 kidney transplant recipients. In addition, we performed modeling of the interaction of either oxPTH or n-oxPTH with the PTH receptor using biophysical structure approaches. Results: The children had the highest mean as well as maximum n-oxPTH concentrations as compared to adult patients (both patients on dialysis as well as kidney transplant recipients). The relationship between oxPTH and n-oxPTH of individual patients varied substantially in all three populations with renal impairment. The analysis of n-oxPTH in 89 healthy control subjects revealed that n-oxPTH concentrations in patient with renal failure were higher as compared to healthy adult controls (2.25-fold in children with renal failure, 1.53-fold in adult patients on dialysis, and 1.56-fold in kidney transplant recipients, respectively). Computer assisted biophysical structure modeling demonstrated, however, minor sterical- and/or electrostatic changes in oxPTH and n-oxPTH. This indicated that PTH oxidation may induce refolding of PTH and hence alters PTH-PTH receptor interaction via oxidation induced three-dimensional structure alteration of PTH. Conclusion: A huge proportion of circulating PTH measured by current state-of-the-art assay systems is oxidized and thus not biologically active. The relationship between oxPTH and n-oxPTH of individual patients varied substantially. Non-oxidized PTH concentrations are 1.5 - 2.25 fold higher in patients with renal failure as compared to health controls. Measurements of n-oxPTH may reflect the hormone status more precise. The iPTH measures describes most likely oxidative stress in patients with renal failure rather than the PTH hormone status. This, however, needs to be demonstrated in further clinical studies. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 343 KW - n-oxPTH KW - chronic renal failure KW - kidney transplantation KW - hemodialysis KW - oxidation KW - PTH KW - chronic renal failure in children Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-399980 ER - TY - THES A1 - Wittenbecher, Clemens T1 - Linking whole-grain bread, coffee, and red meat to the risk of type 2 diabetes T1 - Der Einfluss von Vollkornbrot, Kaffee, und rotem Fleisch auf das Typ 2 Diabetesrisiko BT - using metabolomics networks to infer potential biological mechanisms BT - Verwendung von Metabolomics-Netzwerken, um auf biologische Mechanismen zu schließen N2 - Background: Consumption of whole-grain, coffee, and red meat were consistently related to the risk of developing type 2 diabetes in prospective cohort studies, but potentially underlying biological mechanisms are not well understood. Metabolomics profiles were shown to be sensitive to these dietary exposures, and at the same time to be informative with respect to the risk of type 2 diabetes. Moreover, graphical network-models were demonstrated to reflect the biological processes underlying high-dimensional metabolomics profiles. Aim: The aim of this study was to infer hypotheses on the biological mechanisms that link consumption of whole-grain bread, coffee, and red meat, respectively, to the risk of developing type 2 diabetes. More specifically, it was aimed to consider network models of amino acid and lipid profiles as potential mediators of these risk-relations. Study population: Analyses were conducted in the prospective EPIC-Potsdam cohort (n = 27,548), applying a nested case-cohort design (n = 2731, including 692 incident diabetes cases). Habitual diet was assessed with validated semiquantitative food-frequency questionnaires. Concentrations of 126 metabolites (acylcarnitines, phosphatidylcholines, sphingomyelins, amino acids) were determined in baseline-serum samples. Incident type 2 diabetes cases were assed and validated in an active follow-up procedure. The median follow-up time was 6.6 years. Analytical design: The methodological approach was conceptually based on counterfactual causal inference theory. Observations on the network-encoded conditional independence structure restricted the space of possible causal explanations of observed metabolomics-data patterns. Given basic directionality assumptions (diet affects metabolism; metabolism affects future diabetes incidence), adjustment for a subset of direct neighbours was sufficient to consistently estimate network-independent direct effects. Further model-specification, however, was limited due to missing directionality information on the links between metabolites. Therefore, a multi-model approach was applied to infer the bounds of possible direct effects. All metabolite-exposure links and metabolite-outcome links, respectively, were classified into one of three categories: direct effect, ambiguous (some models indicated an effect others not), and no-effect. Cross-sectional and longitudinal relations were evaluated in multivariable-adjusted linear regression and Cox proportional hazard regression models, respectively. Models were comprehensively adjusted for age, sex, body mass index, prevalence of hypertension, dietary and lifestyle factors, and medication. Results: Consumption of whole-grain bread was related to lower levels of several lipid metabolites with saturated and monounsaturated fatty acids. Coffee was related to lower aromatic and branched-chain amino acids, and had potential effects on the fatty acid profile within lipid classes. Red meat was linked to lower glycine levels and was related to higher circulating concentrations of branched-chain amino acids. In addition, potential marked effects of red meat consumption on the fatty acid composition within the investigated lipid classes were identified. Moreover, potential beneficial and adverse direct effects of metabolites on type 2 diabetes risk were detected. Aromatic amino acids and lipid metabolites with even-chain saturated (C14-C18) and with specific polyunsaturated fatty acids had adverse effects on type 2 diabetes risk. Glycine, glutamine, and lipid metabolites with monounsaturated fatty acids and with other species of polyunsaturated fatty acids were classified as having direct beneficial effects on type 2 diabetes risk. Potential mediators of the diet-diabetes links were identified by graphically overlaying this information in network models. Mediation analyses revealed that effects on lipid metabolites could potentially explain about one fourth of the whole-grain bread effect on type 2 diabetes risk; and that effects of coffee and red meat consumption on amino acid and lipid profiles could potentially explain about two thirds of the altered type 2 diabetes risk linked to these dietary exposures. Conclusion: An algorithm was developed that is capable to integrate single external variables (continuous exposures, survival time) and high-dimensional metabolomics-data in a joint graphical model. Application to the EPIC-Potsdam cohort study revealed that the observed conditional independence patterns were consistent with the a priori mediation hypothesis: Early effects on lipid and amino acid metabolism had the potential to explain large parts of the link between three of the most widely discussed diabetes-related dietary exposures and the risk of developing type 2 diabetes. N2 - Hintergrund: Evidenz aus prospektiven Kohortenstudien belegt, dass der gewohnheitsmäßige Verzehr von Vollkorn, Kaffee und rotem Fleisch mit dem Risiko an Typ 2 Diabetes zu erkranken assoziiert ist. Dieser Risikobeziehung eventuell zugrunde liegende Mechanismen sind allerdings noch weitgehend unklar. Des Weiteren wurde gezeigt, dass Metabolitenprofile im Blut durch die oben genannten Ernährungs-expositionen beeinflusst werden und außerdem in Zusammenhang mit dem Typ 2 Diabetesrisiko stehen. Zusätzlich wurde beschrieben, dass grafische Netzwerkmodelle von Metabolitenprofilen die zugrunde liegenden Stoffwechselprozesse gut abbilden. Zielstellung: Das Ziel dieser Arbeit war es, Hypothesen bezüglich biologischer Mechanismen zu generieren, die die Assoziationen des Vollkornverzehrs, des Kaffeekonsums und des Fleischverzehrs mit dem Typ 2 Diabetesrisiko erklären könnten. Im speziellen sollten Aminosäure- und Lipidprofile als mögliche Mediatoren des Risikozusammenhangs untersucht werden. Studienpopulation: Analysen wurden auf Grundlage von Daten aus der prospektiven EPIC-Potsdam Kohortenstudie (n=27,548) durchgeführt, wobei ein Fall-Kohorten-Design verwendet wurde (n=2317, darunter 692 inzidente Typ 2 Diabetesfälle). Ernährungsgewohnheiten wurden mit einem validierten, semiquantitativen Verzehrshäufigkeitsfragebogen erfasst. Die Konzentrationen von 126 Metaboliten (Aminosäuren, Acylcarnitine, Sphingomyeline und Phosphatidylcholine) wurden zur Basiserhebung genommen Blutproben gemessen. Inzidente Typ 2 Diabetesfälle wurden im Rahmen einer aktiven Folgeerhebung detektiert und verifiziert. Die mediane Dauer des berücksichtigten prospektiven Erhebungszeitraums lag für diese Studie bei 6,6 Jahren. Aufbau der Analysen: Die theoretische Grundlage für den methodischen Ansatz dieser Arbeit bildete die kontrafaktische Theorie der Kausalinferenz. Die in Netzwerken kodierte konditionale Unabhängigkeitsstruktur wurde genutzt, um den Raum möglicher Modelle zu begrenzen, die die beobachteten Zusammenhänge zwischen den Metaboliten erklären könnten. Unter Annahme weniger grundlegender Effektrichtungen (von der Ernährung auf die Netzwerke gerichtete Effekte; von den Netzwerken auf das Diabetesrisiko gerichtete Effekte) genügt die Adjustierung für eine Teilmenge der direkten Nachbarn im Netzwerk, um netzwerkunabhängige direkte Effekte konsistent zu schätzen. Eine weitere Spezifizierung der Modelle war allerdings aufgrund fehlender Richtungsinformationen zu den Metaboliten-abhängigkeiten nicht möglich. Deshalb wurde ein Multi-Modellierungsansatz gewählt, um die Grenzen möglicher Effekte zu schlussfolgern. Alle möglichen Ernährungs-Metaboliten-Beziehungen und Metaboliten-Typ 2 Diabetesrisiko-Beziehungen wurden dadurch in eine der folgenden drei Kategorien klassifiziert: Direkter Effekt, Unklar, Kein Effekt. Querschnittsbeziehungen wurden in multivariabel adjustierten linearen Regressionsmodellen untersucht. Longitudinale Zusammenhänge wurden mit Cox-Regressionsmodellen geschätzt. Alle Modelle wurden für Alter, Geschlecht, Body-Mass-Index, prävalente Hypertonie, Ernährungs- und Lebensstilfaktoren und die Einnahme von Medikamenten adjustiert. Ergebnisse: Der Verzehr von Vollkornbrot stand im Zusammenhang mit niedrigeren Konzentrationen gesättigter und einfach ungesättigter Fettsäuren. Kaffee stand in Beziehung zu niedrigeren Konzentrationen verzweigtkettiger und aromatischer Aminosäuren und hatte potentielle Effekte auf das Fettsäureprofil in den Lipidmetaboliten. Rotes Fleisch zeigte einen Zusammenhang mit niedrigeren Glyzinspiegeln und mit höheren Konzentrationen verzweigtkettiger Aminosäuren. Außerdem stand das Fettsäureprofil in den verschieden Gruppen von Lipidmetaboliten in Zusammenhang mit dem Fleischverzehr. Des Weiteren wurden potentielle Effekte der Metabolite auf das Typ 2 Diabetesrisiko gefunden. Aromatische Aminosäuren und Lipidmetabolite mit geradzahligen, gesättigten (C14-C16) und mit spezifischen mehrfach ungesättigten Fettsäureseitenketten standen mit einem erhöhten Typ 2 Diabetesrisiko in Beziehung. Glyzin, Glutamin und Lipidmetabolite mit einfach ungesättigten und anderen mehrfach ungesättigten Fettsäureseitenketten zeigten einen günstigen Zusammenhang mit dem Diabetesrisiko. Mögliche Mediatoren der Beziehung der Ernährungsexpositionen wurden identifiziert, indem diese Informationen in gemeinsamen grafischen Modellen integriert wurden. Mediationsanalysen zeigten, dass die möglichen Effekte von Vollkornverzehr auf die Lipidmetabolite ungefähr ein Viertel des günstigen Einflusses von Vollkornverzehr auf das Diabetesrisikos erklären könnten. Die möglichen Effekte von Kaffeekonsum und von Fleischverzehr auf Aminosäuren und Lipidmetabolite könnten jeweils ungefähr zwei Drittel der Zusammenhänge mit dem Diabetesrisiko erklären. Schlussfolgerung: Grundlage für die Ergebnisse dieser Arbeit war die Entwicklung eines Algorithmus, der externe Faktoren (kontinuierlich Expositionsvariablen, Ereigniszeit-Daten) und hochdimensionale Metabolitenprofile in einem gemeinsamen grafischen Modell integriert. Die Anwendung dieses Algorithmus auf Daten aus der EPIC-Potsdam Kohortenstudie hat gezeigt, dass die beobachteten konditionalen Unabhängigkeitsstrukturen mit der a priori Mediationshypothese konsistent waren. Der frühe Einfluss auf den Aminosäure- und Lipidstoffwechsel könnte die beobachteten Zusammenhänge zwischen drei wichtigen Ernährungsfaktoren und dem Risiko an Typ 2 Diabetes zu erkranken zu großen Teilen erklären. KW - type 2 diabetes KW - nutrition KW - lipid metabolism KW - metabolomics KW - epidemiology KW - networks KW - graphical models KW - mediation analysis KW - red meat KW - whole-grain KW - Diabetes mellitus Typ 2 KW - Ernährung KW - Fettstoffwechsel KW - Metabolomics KW - Epidemiologie KW - Netzwerke KW - grafische Modelle KW - Mediationsanalyse KW - rotes Fleisch KW - Vollkorn KW - Kaffee KW - coffee Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-404592 ER - TY - GEN A1 - Schmiedchen, Bettina A1 - Longardt, Ann Carolin A1 - Bührer, Christoph A1 - Raila, Jens A1 - Loui, Andrea A1 - Schweigert, Florian J. T1 - The Relative Dose Response Test Based on Retinol-Binding Protein 4 Is Not Suitable to Assess Vitamin A Status in Very Low Birth Weight Infants N2 - Background: The relative dose response (RDR) test, which quantifies the increase in serum retinol after vitamin A administration, is a qualitative measure of liver vitamin A stores. Particularly in preterm infants, the feasibility of the RDR test involving blood is critically dependent on small sample volumes. Objectives: This study aimed to assess whether the RDR calculated with retinol-binding protein 4 (RBP4) might be a substitute for the classical retinol-based RDR test for assessing vitamin A status in very preterm infants. Methods: This study included preterm infants with a birth weight below 1,500 g (n = 63, median birth weight 985 g, median gestational age 27.4 weeks) who were treated with 5,000 IU retinyl palmitate intramuscularly 3 times a week for 4 weeks. On day 3 (first vitamin A injection) and day 28 of life (last vitamin A injection), the RDR was calculated and compared using serum retinol and RBP4 concentrations. Results: The concentrations of retinol (p < 0.001) and RBP4 (p < 0.01) increased significantly from day 3 to day 28. On day 3, the median (IQR) retinol-RDR was 27% (8.4-42.5) and the median RBP4-RDR was 8.4% (-3.4 to 27.9), compared to 7.5% (-10.6 to 20.8) and -0.61% (-19.7 to 15.3) on day 28. The results for retinol-RDR and RBP4-RDR revealed no significant correlation. The agreement between retinol-RDR and RBP4-RDR was poor (day 3: Cohen's κ = 0.12; day 28: Cohen's κ = 0.18). Conclusion: The RDR test based on circulating RBP4 is unlikely to reflect the hepatic vitamin A status in preterm infants. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 342 KW - relative dose response test KW - vitamin A KW - preterm infant Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-399853 ER - TY - THES A1 - Kasch, Juliane T1 - Impact of maternal high-fat consumption on offspring exercise performance, skeletal muscle energy metabolism, and obesity susceptibility T1 - Einfluss der maternalen Ernährung auf den Energiestoffwechsel des Skelettmuskels, die Ausdauerleistung und die Adipositasentwicklung der Nachkommen N2 - Background: Obesity is thought to be the consequence of an unhealthy nutrition and a lack of physical activity. Although the resulting metabolic alterations such as impaired glucose homeostasis and insulin sensitivity can usually be improved by physical activity, some obese patients fail to enhance skeletal muscle metabolic health with exercise training. Since this might be largely heritable, maternal nutrition during pregnancy and lactation is hypothesized to impair offspring skeletal muscle physiology. Objectives: This PhD thesis aims to investigate the consequences of maternal high-fat diet (mHFD) consumption on offspring skeletal muscle physiology and exercise performance. We could show that maternal high-fat diet during gestation and lactation decreases the offspring’s training efficiency and endurance performance by influencing the epigenetic profile of their skeletal muscle and altering the adaptation to an acute exercise bout, which in long-term, increases offspring obesity susceptibility. Experimental setup: To investigate this issue in detail, we conducted several studies with a similar maternal feeding regime. Dams (C57BL/6J) were either fed a low-fat diet (LFD; 10 energy% from fat) or high-fat diet (HFD; 40 energy% from fat) during pregnancy and lactation. After weaning, male offspring of both maternal groups were switched to a LFD, on which they remained until sacrifice in week 6, 15 or 25. In one study, LFD feeding was followed by HFD provision from week 15 until week 25 to elucidate the effects on offspring obesity susceptibility. In week 7, all mice were randomly allocated to a sedentary group (without running wheel) or an exercised group (with running wheel for voluntary exercise training). Additionally, treadmill endurance tests were conducted to investigate training performance and efficiency. In order to uncover regulatory mechanisms, each study was combined with a specific analytical setup, such as whole genome microarray analysis, gene and protein expression analysis, DNA methylation analyses, and enzyme activity assays. Results: mHFD offspring displayed a reduced training efficiency and endurance capacity. This was not due to an altered skeletal muscle phenotype with changes in fiber size, number, and type. DNA methylation measurements in 6 week old offspring showed a hypomethylation of the Nr4a1 gene in mHFD offspring leading to an increased gene expression. Since Nr4a1 plays an important role in the regulation of skeletal muscle energy metabolism and early exercise adaptation, this could affect offspring training efficiency and exercise performance in later life. Investigation of the acute response to exercise showed that mHFD offspring displayed a reduced gene expression of vascularization markers (Hif1a, Vegfb, etc) pointing towards a reduced angiogenesis which could possibly contribute to their reduced endurance capacity. Furthermore, an impaired glucose utilization of skeletal muscle during the acute exercise bout by an impaired skeletal muscle glucose handling was evidenced by higher blood glucose levels, lower GLUT4 translocation and diminished Lactate dehydrogenase activity in mHFD offspring immediately after the endurance test. These points towards a disturbed use of glucose as a substrate during endurance exercise. Prolonged HFD feeding during adulthood increases offspring fat mass gain in mHFD offspring compared to offspring from low-fat fed mothers and also reduces their insulin sensitivity pointing towards a higher obesity and diabetes susceptibility despite exercise training. Consequently, mHFD reduces offspring responsiveness to the beneficial effects of voluntary exercise training. Conclusion: The results of this PhD thesis demonstrate that mHFD consumption impairs the offspring’s training efficiency and endurance capacity, and reduced the beneficial effects of exercise on the development of diet-induced obesity and insulin resistance in the offspring. This might be due to changes in skeletal muscle epigenetic profile and/or an impaired skeletal muscle angiogenesis and glucose utilization during an acute exercise bout, which could contribute to a disturbed adaptive response to exercise training. N2 - Hintergrund: Übergewicht ist die Folge einer ungesunden Ernährung und einem Mangel an körperlicher Aktivität. Obwohl die daraus resultierenden metabolischen Veränderungen wie die beeinträchtigte Glukose-Homöostase und die Insulinsensitivität in der Regel durch körperliche Aktivität verbessert werden können, sind einige adipöse Patienten nicht in der Lage ihren Skelettmuskel-Metabolismus durch regelmäßiges Training zu verbessern. Da dies weitgehend vererbbar sein könnte, wird vermutet, dass die maternale Ernährung während der Gestation und Laktation einen beeinträchtigten Energiestoffwechsel des Skelettmuskels der Nachkommen begünstigt. Ziel: Ziel dieser Dissertation war es, den Einfluss der maternalen Hochfett-Diät (mHFD) auf den Skelettmuskel des Nachkommens zu untersuchen. Wir konnten zeigen, dass eine mHFD während der Gestation und Laktation die Trainingseffizienz und die Ausdauerleistung der Nachkommen verringert, verursacht durch die Veränderung des epigenetischen Profils des Skelettmuskels der Nachkommen und der verminderten Anpassung an eine akute Trainingsleistung, was langfristig die Anfälligkeit für die Entwicklung einer Adipositas im Nachkommen erhöht. Experimentelles Setup: Um dieses Thema ausführlich zu erforschen, hatten wir ein komplexes Studiendesign. Allen vier Studien ging dasselbe maternale Fütterungsregime voraus. Weibliche C57BL/6J Mäuse wurden entweder mit einer Niedrigfett-Diät (LFD; 10 Energie% aus Fett) oder Hochfett-Diät (HFD; 40 Energie% aus Fett) während der Gestation und Laktation gefüttert. Nach Absatz wurden die männlichen Nachkommen beider Gruppen auf eine LFD umgestellt, auf der sie bis zum Ende der jeweiligen Studie in der Woche 6, 15 oder 25 blieben. In einer Studie folgte auf die LFD-Fütterung eine HFD-Versorgung von Woche 15 bis Woche 25, um den Einfluss der maternalen Diät auf die Entwicklung einer Adipositas der Nachkommen aufzuklären. In der 7. Woche wurden alle Mäuse zufällig einer sesshaften Gruppe (ohne Laufrad) oder einer Trainingsgruppe (mit Laufrad für freiwilliges Trainingstraining) zugewiesen. Darüber hinaus wurden Laufband-Ausdauertests durchgeführt, um die Trainingsleistung und -effizienz zu untersuchen. Um die regulatorischen Mechanismen aufzudecken, wurde jede Studie mit einem spezifischen analytischen Aufbau kombiniert, wie z. B. einer Mikroarray-Analyse, Gen- und Protein-Expressionsanalysen, DNA-Methylierungsanalysen und Enzymaktivitäts-Assays. Ergebnisse: mHFD Nachkommen zeigten eine reduzierte Trainingseffizienz und Ausdauerkapazität. Dies ist nicht auf einen veränderten Skelettmuskel-Phänotyp mit Veränderungen der Muskelfasergröße, der Anzahl und der Muskelfasertypen zurückzuführen. DNA-Methylierungsmessungen bei 6 Wochen alten Nachkommen zeigten eine Hypomethylierung des Nr4a1-Gens in mHFD-Nachkommen, was wiederum in einer erhöhten Genexpression resultierte. Da Nr4a1 eine wichtige Rolle bei der Regulierung des Skelettmuskel-Energiestoffwechsels und der frühen Trainingsanpassung spielt, könnte dies die Trainingseffizienz und -leistung der Nachkommen im späteren Leben beeinflussen. Bei der Untersuchung der Reaktion auf eine akute Ausdauerleistung zeigten die mHFD-Nachkommen eine reduzierte Genexpression von Vaskularisierungsmarkern (Hif1a, Vegfb usw.), die auf eine reduzierte Angiogenese hindeuteten, welche eine Ursache für ihre verminderte Ausdauerkapazität darstellen könnte. Darüber hinaus wurde eine beeinträchtigte Glucoseverwertung des Skelettmuskels während des akuten Ausdauertrainings durch eine beeinträchtigte Glucose-Nutzung des Skelettmuskels mit erhöhten Blutzuckerwerten, einer verminderten GLUT4-Translokation und Laktatdehydrogenase-Aktivität in mHFD-Nachkommen unmittelbar nach dem Ausdauertest gezeigt. Dies weist auf eine gestörte Verwertung der Glucose als Substrat während des Ausdauertrainings hin. Länger andauernde HFD-Fütterung während des Erwachsenenalters erhöht die Fettmasse in mHFD-Nachkommen im Vergleich zu mLFD-Nachkommen und verringert zudem ihre Insulinsensitivität, was Hinweise auf eine erhöhte Adipositas- und Diabetes-Anfälligkeit gibt. Folglich führt die mHFD zu einer verminderten Anpassung der Nachkommen an die positiven Effekte des freiwilligen Laufrad-Trainings. Schlussfolgerung: Die Ergebnisse dieser Dissertation zeigen, dass der mHFD-Konsum die Trainingseffizienz und Ausdauerkapazität der Nachkommen beeinträchtigt, was die Adipositas- und Diabetes-Anfälligkeit im Erwachsenenalter erhöhen kann. Dies könnte auf Veränderungen im epigenetischen Profil des Skelettmuskels und/oder Beeinträchtigungen der Angiogenese und Glukoseverwertung im Skelettmuskel während eines akuten Ausdauertrainings zurückzuführen sein, was zu einer gestörten Anpassung der Nachkommen an das Training beitragen könnte. KW - maternal diet KW - offspring KW - exercise performance KW - skeletal muscle KW - obesity KW - maternale Ernährung KW - Nachkommen KW - Ausdauerleistung KW - Skelettmuskel KW - Adipositas Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-409703 ER - TY - GEN A1 - Raila, Jens A1 - Schweigert, Florian J. A1 - Kohn, Barbara T1 - C-reactive protein concentrations in serum of dogs with naturally occurring renal disease N2 - The current study was undertaken to investigate the relation between serum C-reactive protein (CRP) concentrations and parameters of renal function in dogs with naturally occurring renal disease. Dogs were assigned to groups according to plasma creatinine concentration, urinary protein-to-creatinine ratio (UP/UC), and exogenous plasma creatinine clearance (P-Cl(Cr)) rates. Group A (healthy control dogs; n = 8): non-azotemic (plasma creatinine <125 mu mol/l) and nonproteinuric (UP/UC <0.2), with P-Cl(Cr) rates >90 ml/min/m(2); group B (n = 11): non-azotemic, nonproteinuric dogs with reduced P-Cl(Cr) rates (50-89 ml/min/m(2)); group C (n = 7): azotemic, borderline proteinuric dogs (P-Cl(Cr) rates: 22-67 ml/min/m(2)); and group D (n = 6): uremic, proteinuric dogs (not tested for P-Cl(Cr)). The serum CRP concentrations were measured via commercial enzyme-linked immunosorbent assay. The CRP concentrations in the clinically healthy dogs (group A) ranged from 2.09 mg/l to 8.60 mg/l (median: 3.21 mg/l). In comparison with dogs of group A, median CRP concentrations were significantly (P < 0.01) elevated in dogs of group B (17.6 mg/l, range: 17.0-19.2 mg/l), group C (24.8 mg/l, range: 18.0-32.5 mg/l), and group D (59.7 mg/l, range: 17.7-123 mg/l). Serum CRP was significantly related to P-Cl(Cr) (r = -0.83; P < 0.001), plasma creatinine (r = 0.81; P < 0.001), UP/UC (r = 0.70; P < 0.001), and leukocytes (r = 0.49; P < 0.01). The significant relations between serum CRP concentrations and biochemical parameters of kidney function in plasma and urine suggest that a stimulation of the acute phase response is implicated in the pathogenesis of canine renal disease. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 407 KW - C-reactive protein KW - dogs KW - proteinuria KW - renal disease Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-402942 ER - TY - GEN A1 - Gerecke, Christian A1 - Edlich, Alexander A1 - Giulbudagian, Michael A1 - Schumacher, Fabian A1 - Zhang, Nan A1 - Said, Andre A1 - Yealland, Guy A1 - Lohan, Silke B. A1 - Neumann, Falko A1 - Meinke, Martina C. A1 - Ma, Nan A1 - Calderón, Marcelo A1 - Hedtrich, Sarah A1 - Schäfer-Korting, Monika A1 - Kleuser, Burkhard T1 - Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes N2 - Novel nanogels that possess the capacity to change their physico-chemical properties in response to external stimuli are promising drug-delivery candidates for the treatment of severe skin diseases. As thermoresponsive nanogels (tNGs) are capable of enhancing penetration through biological barriers such as the stratum corneum and are taken up by keratinocytes of human skin, potential adverse consequences of their exposure must be elucidated. In this study, tNGs were synthesized from dendritic polyglycerol (dPG) and two thermoresponsive polymers. tNG_dPG_tPG are the combination of dPG with poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)) and tNG_dPG_pNIPAM the one with poly(N-isopropylacrylamide) (pNIPAM). Both thermoresponsive nanogels are able to incorporate high amounts of dexamethasone and tacrolimus, drugs used in the treatment of severe skin diseases. Cellular uptake, intracellular localization and the toxicological properties of the tNGs were comprehensively characterized in primary normal human keratinocytes (NHK) and in spontaneously transformed aneuploid immortal keratinocyte cell line from adult human skin (HaCaT). Laser scanning confocal microscopy revealed fluorescently labeled tNGs entered into the cells and localized predominantly within lysosomal compartments. MTT assay, comet assay and carboxy-H2DCFDA assay, demonstrated neither cytotoxic or genotoxic effects, nor any induction of reactive oxygen species of the tNGs in keratinocytes. In addition, both tNGs were devoid of eye irritation potential as shown by bovine corneal opacity and permeability (BCOP) test and red blood cell (RBC) hemolysis assay. Therefore, our study provides evidence that tNGs are locally well tolerated and underlines their potential for cutaneous drug delivery. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 335 KW - Drug delivery KW - nanoparticles KW - particle characterization KW - keratinocytes KW - nanotoxicology Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-395325 ER - TY - GEN A1 - Lohren, Hanna A1 - Bornhorst, Julia A1 - Fitkau, Romy A1 - Pohl, Gabriele A1 - Galla, Hans-Joachim A1 - Schwerdtle, Tanja T1 - Effects on and transfer across the blood-brain barrier in vitro BT - Comparison of organic and inorganic mercury species N2 - Background: Transport of methylmercury (MeHg) across the blood-brain barrier towards the brain side is well discussed in literature, while ethylmercury (EtHg) and inorganic mercury are not adequately characterized regarding their entry into the brain. Studies investigating a possible efflux out of the brain are not described to our knowledge. Methods: This study compares, for the first time, effects of organic methylmercury chloride (MeHgCl), EtHg-containing thiomersal and inorganic Hg chloride (HgCl2) on as well as their transfer across a primary porcine in vitro model of the blood-brain barrier. Results: With respect to the barrier integrity, the barrier model exhibited a much higher sensitivity towards HgCl2 following basolateral incubation (brain-facing side) as compared to apical application (blood-facing side). These HgCl2 induced effects on the barrier integrity after brain side incubation are comparable to that of the organic species, although MeHgCl and thiomersal exerted much higher cytotoxic effects in the barrier building cells. Hg transfer rates following exposure to organic species in both directions argue for diffusion as transfer mechanism. Inorganic Hg application surprisingly resulted in a Hg transfer out of the brain-facing compartment. Conclusions: In case of MeHgCl and thiomersal incubation, mercury crossed the barrier in both directions, with a slight accumulation in the basolateral, brain-facing compartment, after simultaneous incubation in both compartments. For HgCl2, our data provide first evidence that the blood-brain barrier transfers mercury out of the brain. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 406 KW - organic mercury KW - inorganic mercury KW - methylmercury KW - thiomersal KW - mercuric mercury KW - in vitro blood-brain barrier model Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-401776 ER -