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Background High blood glucose and diabetes are amongst the conditions causing the greatest losses in years of healthy life worldwide. Therefore, numerous studies aim to identify reliable risk markers for development of impaired glucose metabolism and type 2 diabetes. However, the molecular basis of impaired glucose metabolism is so far insufficiently understood. The development of so called 'omics' approaches in the recent years promises to identify molecular markers and to further understand the molecular basis of impaired glucose metabolism and type 2 diabetes. Although univariate statistical approaches are often applied, we demonstrate here that the application of multivariate statistical approaches is highly recommended to fully capture the complexity of data gained using high-throughput methods. Methods We took blood plasma samples from 172 subjects who participated in the prospective Metabolic Syndrome Berlin Potsdam follow-up study (MESY-BEPO Follow-up). We analysed these samples using Gas Chromatography coupled with Mass Spectrometry (GC-MS), and measured 286 metabolites. Furthermore, fasting glucose levels were measured using standard methods at baseline, and after an average of six years. We did correlation analysis and built linear regression models as well as Random Forest regression models to identify metabolites that predict the development of fasting glucose in our cohort. Results We found a metabolic pattern consisting of nine metabolites that predicted fasting glucose development with an accuracy of 0.47 in tenfold cross-validation using Random Forest regression. We also showed that adding established risk markers did not improve the model accuracy. However, external validation is eventually desirable. Although not all metabolites belonging to the final pattern are identified yet, the pattern directs attention to amino acid metabolism, energy metabolism and redox homeostasis. Conclusions We demonstrate that metabolites identified using a high-throughput method (GC-MS) perform well in predicting the development of fasting plasma glucose over several years. Notably, not single, but a complex pattern of metabolites propels the prediction and therefore reflects the complexity of the underlying molecular mechanisms. This result could only be captured by application of multivariate statistical approaches. Therefore, we highly recommend the usage of statistical methods that seize the complexity of the information given by high-throughput methods., Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe, 850

We report on a case of very rare autosomal recessive cholesteryl ester storage disease due to lysosomal acid lipase deficiency (LALD). LALD is caused by mutations in the lysosomal acid lipase A (LIPA) gene resulting in cholesteryl ester accumulation in liver, spleen, and macrophages. It can lead to liver failure, accelerated atherosclerosis and premature death. Until recently, treatment options were limited to lipid-lowering medications to control dyslipidemia. Presently, a long-term enzyme replacement therapy with Sebelipase alfa, a recombinant human lysosomal acid lipase, is available for patients with LALD.Our patient's condition became conspicuous at the age of two due to a xanthogranuloma of the chin together with increased lipid levels, elevated liver enzymes and hepatomegaly. It took another five years until our patient was diagnosed with LALD after genetic testing. A bi-weekly therapy with intravenous Sebelipase alfa was started at the age of 26 years. It led to normalization of lipid levels, reduction of liver enzymes and beginning regression of hepatomegaly in the absence of adverse drug reactions after 46 infusions.Since LALD can take a fatal course even in patients with a long-term stable condition, it is essential to identify affected patients early and to treat them appropriately by enzyme replacement therapy. LALD should be suspected in patients with low high-density lipoprotein cholesterol (HDL-C) and high low-density lipoprotein cholesterol (LDL-C) in conjunction with elevated liver enzymes or hepatomegaly.A registry for LALD patients shall help to advance our understanding of the disease as well as improve patient care (NCT01633489). Keywords: Lysosomal acid lipase deficiency (LALD), Cholesteryl ester storage disease, Sebelipase alfa (Kanuma™), LALD registry

1\. Deckblatt 2\. Inhaltsverzeichnis 3\. Einleitung 4\. Material und Methoden 5\. Ergebnisse 6\. Diskussion 7\. Zusammenfassung 8\. Abkürzungsverzeichnis 9\. Literaturverzeichnis 10\. Danksagung 11\. Lebenslauf, Glatte Gefäßmuskelzellen sind aufgrund ihrer Kontraktionsfähigkeit wesentlich an der Regulation des Blutdrucks und der Blutzirkulation beteiligt. Im Gegensatz zu Skelett- und Herzmuskelzellen sind sie jedoch nicht terminal differenziert und können durch verschiedene Stimuli zur phänotypischen Modulation angeregt werden. Diese Veränderung des Phänotyps ist eine wesentliche Voraussetzung zur Entwicklung von Atherosklerose. Im Rahmen dieser Prozesse kommt es zu einer Erhöhung der Proliferationsrate glatter Gefäßmuskelzellen. Parallel dazu kommt es zu einer verminderten Expression kontraktiler Proteine, wie z.B. SM-MHC, die typisch für differenzierte glatte Gefäßmuskelzellen sind. Von therapeutischem Interesse ist es daher diesen Vorgang der Dedifferenzierung zu inhibieren und eine Differenzierung glatter Gefäßmuskelzellen zu induzieren. Das Ziel der vorliegenden Arbeit war es, Signaltransduktionsmechanismen zu identifizieren und zu charakterisieren, die in vitro an der phänotypischen Modulation neonataler glatter Gefäßmuskelzellen beteiligt sind. Um dieser Fragestellung nachzugehen wurde die Thrombin- induzierte Steigerung der SM-MHC-Promotor-Aktivität in neonatalen glatten Gefäßmuskelzellen der Ratte untersucht. Thrombin führt dabei über die Aktivierung eines Proteinase aktivierten Rezeptors zu einer Aktivierung des Gi-Proteins. Eine Beteiligung an der Signalkaskade durch andere G-Proteine, die an den Proteinase aktivierten Rezeptor koppeln, konnte ausgeschlossen werden. Außerdem konnte die Gβγ-Untereinheit des Gi-Proteins als die Untereinheit identifiziert werden, über die das Signal vermittelt wird. Als weiterer Bestandteil der Signalkaskade konnte eine intrazelluläre Ca++-Konzentrationserhöhung nachgewiesen werden. Weiterhin führt das Signal über die Kinase MEK zu einer biphasischen Kinetik der ERK1/2-Phosphorylierung. Diese biphasische Kinetik bewirkt eine Aktivierung des SM-MHC Promotors und somit einer Expression von SM-MHC., Vascular smooth muscle cells (VSMC) are due to their possibility of contraction essentially involved in the regulation of bloodpressure and bloodcirculation. In contrast to skeletalmuscle- or heartmusclecells they are not terminal differentiated and can undergo a phenotypical modulation by many stimuli. This change in the phenotye is an important condition for the pathogenesis of atheriosclerosis. In the context of this process it comes to an increase of proliferation of VSMC. Parallel there is also o a decreased expression of contractile proteins such as smooth muscle- myosin heavy chain (SM-MHC), which are typical for VSMC. It could be therefore of therapeutical interest to inhibit this process of dedifferentiation and to induce a differentiation of VSMC. The target of this work was to identify and to characterize mechanisms of signaling, which are involved in the penotypical modulation of VSMC. To answer these questions, the thrombin induced increased SM-MHC-promoter-CAT-activity in VSMC of the rat which was examined. Thrombin activates trough a proteinase activated receptor a Gi-protein. A paticipation at this signalling cascade of other G-proteins at this receptor could be excluded. Furthermore it could be showed, that the Gβγ-subunit of the Gi- protein is involved in the cascade. As another part of the cascade an intracellular increase of calcium was proven. Further on, the signal leads by the kinase MEK to a biphasic phosphorylation of the extracellular signal- regulated kinase (ERK). This biphasic kinetics affects an activation of the SM-MHC promoter and therefore an expression of SM-MHC.