Title Promoter Affiliations Abstract "Development of a functional model to determine the pathogenicity of COL4A1- and COL4A2-variants of unknown significance in cerebrovascular disorders and aortic aneurysms." "Marije Meuwissen" "Medical Genetics (MEDGEN)" "COL4A1- and COL4A2-related disorders cause a broad spectrum of problems comprising abnormal brain development, brain hemorrhage at any age, aneurysms (local dilatations) of the brain arteries, but also eye or renal problems. In clinical practice, both genes are studied in disorders of brain vasculature or development and are included in gene panels to study individuals with intellectual disability. These investigations sometimes identify variants of unknown significance (VUS). Because of the important consequences of truly disease-causing mutations, it is of great importance to interpret these variants correctly. In addition, in research setting it was found that COL4A1- and COL4A2-mutations may influence the occurrence of aortic aneurysms. However, further studies are needed. We will develop a zebrafish model to study the effect of variants of unknown significance. No zebrafish model currently exists to study COL4A1- and COL4A2-related disorders. We will start with introducing known disease-causing mutations and study their effect on zebrafish development using a fish that has fluorescent blood vessels in order to easily pick up abnormal vessels. We will study the occurrence of brain haemorrhage, changes in movement patterns and the basement membrane, a structure that stabilizes the wall of blood vessels and measure the aortic diameter. After identifying the abnormalities in true disease-causing mutations, it is possible to study whether VUS contribute to disease." "Studies of the ErbB4 receptor in myocardial non-myocytes to create new opportunities for the treatment of cardiac disease." "Gilles De Keulenaer" "Physiopharmacology (PHYSPHAR)" "It has been recently discovered that activation of ErbB2 receptor signaling in cardiac muscle is a physiological response of the heart to cope with overload and injury, and may even lead to cardiac regeneration. Researchers try to translate these findings into pharmacological applications, which would be a significant contribution to clinical cardiology. To date, the easiest way to activate ErbB2 in the heart is treatment with neuregulin-1, a protein growth factor activating ErbB3 and ErbB4, both co-receptors of ErbB2. However, treatment with neuregulin-1 has disadvantages, and there is a need for the development of small chemical molecules, replacing neuregulin-1. This development is starting, but fundamental questions remain. Most importantly, the differential role of ErbB3 or ErbB4 receptors in the different cell types of the heart remains unclear. Based on previous research in our laboratory, we believe that activation of ErbB4 is indispensable for the effects of neuregulin-1 in the heart, both in myocytes and non-myocytes of the cardiac muscle. In this project we test the hypothesis that genetic deletion of ErbB4 in non-myocytes of rodent models makes heart failure a more aggressive disease and attenuates the pharmacological effects of neuregulin-1 in heart failure. If this hypothesis is true, it underscores pharmacological development of chemical agonists of ErbB4 to treat cardiac diseases, and better defines their working mechanism." "Autophagy induction as mechanism of action in cardiovascular disease prevention by olive polyphenols." "Lynn Roth" "Physiopharmacology (PHYSPHAR)" "Atherosclerotic plaque rupture is the leading cause of acute cardiovascular syndromes and is responsible for 3.9 million deaths in Europe every year. Preventive strategies are greatly needed to reduce the health care burden of cardiovascular disease (CVD). The Mediterranean diet results in a lower CVD risk, with virgin olive oil as its key element. Many of the health-promoting effects are ascribed to the olive polyphenols (OPs), which are known to be antioxidants, but recently a link with autophagy induction was shown. Autophagy is a cellular housekeeping mechanism and autophagy deficiency is detrimental in the development of CVD. Thus, inducing autophagy is likely to be an effective preventive strategy. OPs were identified as natural autophagy inducers, but further research is needed to define the contribution of this mechanism to their atheroprotective effects. Therefore, we aim to elucidate the role of endothelial cell autophagy in the atheroprotective properties of OPs. The research objectives are divided in 2 work packages: (1) Selection of the most potent autophagy-inducing OP and the most therapeutically effective dose, (2) Investigation of the atheroprotective effects of an OP and the role of endothelial cell autophagy. This project will give insight in the mechanism of action of OPs and is an important step towards the implementation of OP nutraceuticals for the prevention of cardiovascular disease." "Activating the neuregulin-1/ErbB4 pathway for treatment of heart failure." "Vincent Segers" "Physiopharmacology (PHYSPHAR)" "Neuregulin-1 (NRG-1) is the natural agonist of the ErbB4 receptor. The NRG-1/ErbB4 system has protective effects in various chronic disorders including chronic heart failure. NRG-1 is currently tested in phase 3 clinical trials for the treatment of chronic heart failure. However, recombinant NRG-1 has to be injected intravenously in the hospital, which is an issue that severely limits applicability of NRG-1 in chronic disorders. A small molecule that can act as an ErbB4 agonist could be administered orally; but currently, there are no small molecule agonists of ErbB4. In this project, we will use an assay that detects pairing of 2 subunits of the ErbB4 receptor. Binding of an agonist to one ErbB4 receptor subunit induces it to interact with its partner, resulting in a readable signal. We will use this assay to screen a chemical diversity Library consisting of 10.000 compounds at the VIB Compound Screening Facility. Hits will be further evaluated for potency, dose-dependency, solubility, receptor specificity using different in vitro assays. We will also evaluate pharmacokinetics and in vitro toxicity. We will test the compound with the highest potency and receptor specificity in validated rodent models of heart failure. Success of this project results in a small molecule agonist of ErbB4, which might lead to novel cures for various chronic diseases." "Stabilization of atherosclerotic plaques via inhibition of regulated necrosis." "Guido De Meyer" "Medicinal Chemistry (UAMC), Physiopharmacology (PHYSPHAR)" "Necrosis is a type of cell death characterized by a gain in cell volume, swelling of organelles, rupture of the plasma membrane and subsequent loss of intracellular contents. For a long time, the process has been considered as a merely accidental and uncontrolled form of cell death, but accumulating evidence suggests that it can also occur in a regulated fashion. Necroptosis is the most understood form of regulated necrosis and requires receptor interacting protein (RIP) kinases as key regulators, but also other examples such as ferroptosis are emerging. Morphological studies using transmission electron microscopy indicate that the vast majority of dying cells in advanced human atherosclerotic plaques undergo necrosis. Although the role of necrosis in atherosclerosis remains ill-defined, a growing body of evidence suggests that necrotic death stimulates atherogenesis and plaque instability through induction of inflammation and enlargement of the necrotic core. Therefore, the following objectives are defined in the present research proposal: (1) Identification of potential beneficial effects of macrophage-specific RIP1 gene deletion on atherosclerosis development, and (2) stabilization of atherosclerotic plaques with potent and selective inhibitors targeting RIP1 kinase activity or ferroptosis. The project may contribute to the development of novel (add-on) therapies for stabilization of atherosclerotic plaques." "Carboxypeptidase U - a new drug target for the improvement of treatment in acute ischemic stroke." "Medical Biochemistry" "Thrombolysis with tissue plasminogen activator remains the only approved pharmacological treatment for acute ischemic stroke, AIS. Besides the narrow therapeutic time window, its use is limited by its efficacy: in up to 50% of the treated patients, timely recanalization is not achieved. Moreover, administration involves serious side effects such as intracranial hemorrhage and neurotoxicity. Consequently, the search for new agents for improvement of AIS treatment is urgently needed. Research has demonstrated that the enzyme carboxypeptidase U (CPU, TAFIa) is an important player in thrombus lysis. After activation from its precursor proCPU, the released CPU is able to potently attenuate fibrinolysis. Consequently, inhibition of CPU activity is a novel approach to enhance fibrinolysis. We want to explore the involvement of this enzyme in AIS in more detail. The usefulness of CPU as a diagnostic marker to discriminate ischemic from hemorrhagic stroke and the relationship of CPU with clinical outcome and thrombolytic treatment efficacy will be investigated. We plan to optimize the Thrombodynamics assay in order to assess the effect of CPU-inhibition on clot lysis during thrombolysis. Furthermore, in a preclinical setting, we will evaluate the effect of CPU inhibition in an experimental stroke model in rats. This research will provide essential information on the role of the CPU system and the usefulness of CPU inhibitors as potentially efficient and safer treatment of AIS." "Development of a functional assay to determine the pathogenicity of genetic variants with unknown significance identified in patients with cardiac arrhythmia." "Dirk Snyders" "Veterinary physiology and biochemistry, Molecular, Cellular and Network Excitability (MCNE)" "Inherited Cardiac Arrhythmia (ICA) refers to a group of genetic disorders in which patients present with abnormal and potentially harmful heart rhythm. These episodes often go unnoticed, but can lead to fainting and sudden cardiac death. At present, over 50 ICA genes have been identified. With the advent of next generation sequencing technology it is possible to test all of these genes simultaneously in multiple ICA patients with a single test. This method proficiently identifies clear disease causing genetic alterations. However, as the number of genes involved increases through better mechanistic insight into disease modifier genes and polymorphisms, we are confronted with a high number of genetic alterations for which causality is unsure. These pose a major challenge for the management of ICA patients. Therefore, the aim of this project is to develop a functional tool that will allow to test the functional impact of variants of unknown significance. We have developed a zebrafish assay in which the electrical dynamics of the heart are reported by fluorescent light signals. As zebrafish are translucent in early development, this model lends itself perfectly to visualize these signals 'in vivo' and at an exceptional resolution. After validating this tool with known pathogenic alterations, we will apply this method to evaluate variants of unknown significance and test the possible arrhythmogenic side effects of some drugs. This innovative approach will allow the clinicians to deliver true personalized medicine." "Identificatie van kleine moleculaire ErbB4 agonisten ter behandeling van cardiovasculaire ziekten." "Gilles De Keulenaer" "Physiopharmacology (PHYSPHAR)" "Neuregulin-1 (NRG-1) is the natural paracrine agonist of the ErbB4 receptor. There is overwhelming evidence that the cardiac NRG-1/ErbB4 system is activated in chronic heart failure (CHF), exerting disease mitigating and regenerative effects. Based on these data from both animals and humans, NRG-1 is developed as a drug for CHF. Clinical trials are performed, and have progressed to stage III (NCT01251406, NCT1214096, and NCT01541202). In addition, there is solid evidence from animals studies that the NRG-1/ErbB4 pathway is involved in other chronic diseases, such as diabetic nephropathy, pulmonary hypertension, atherosclerosis and fibrotic disorders. All of these are common chronic disorders, and potential therapeutic targets for NRG-1. To date, the only way to activate the NRG-1/ErbB4 pathway in vivo is to inject recombinant NRG-1 (rhNRG-1) intravenously. In clinical trials, this is performed over the course of 6-8 hours, which limits applicability of rhNRG-1 in chronic disorders. A small molecule, acting as an ErbB4 agonist would circumvent the drawbacks of a recombinant protein and might be more efficacious in treatment of chronic diseases. Currently, there are no small molecule agonists of ErbB4 identified. In this project, we propose a multi-disciplinary project, including a high throughput experiment using a chemical library to identify agonists of the ErbB4 receptor (OBJECTIVE 1), to test the compound with the highest potency and receptor specificity in validated rodent models of CHF (OBJECTIVE 2), and to define specific patient populations in the heterogeneous field of cardiovascular diseases that could benefit from ErbB4 agonists by quantifying serum levels of neuregulin-1 in human patients (OBJECTIVE 3)." "Identification of small molecule ErbB4 agonists for treatment of heart failure." "Vincent Segers" "Physiopharmacology (PHYSPHAR)" "Neuregulin-1 (NRG-1) is the natural activator (agonist) of the ErbB4 receptor. NRG-1 has protective effects in chronic heart failure, which is a common and deadly disorder. NRG-1 is currently tested in patients for the treatment of chronic heart failure. However, NRG-1 is a protein and has to be injected intravenously in the hospital over the course of 6-8 hours, which makes it difficult to administer NRG-1 in chronic disorders. A small molecule that activates ErbB4 similarly to NRG-1 could be administered orally and might be more effective. Currently, there are no small molecule agonists of ErbB4 identified.In this project, we propose a high throughput screening experiment using a library of 10.000 chemical substances to identify agonists of ErbB4. We will use a genetically engineered cell line that detects activation of the ErbB4 receptor upon binding of an agonist. Pairing of the receptors leads to activation of an enzyme which will generate a light emitting product. This signal can rapidly be detected by an automatic reader. After in-house optimization of the assay, we will screen a chemical Library consisting of 10.000 compounds at the VIB Compound Screening Facility.In conclusion, NRG-1 has protective effects in heart failure, but the route of administration is prohibitive for wider applicability in the clinic. If this project is successful in identifying a small molecule agonist of ErbB4, we might have the key to a new treatment for heart failure." "Identification of novel therapeutic targets of Brugada Syndrome through discovery and characterization of genetic modifiers." "Bart Loeys" "Medical Genetics (MEDGEN)" "Brugada syndrome (BrS) is an inherited electrical disorder of the heart, presenting in patients with an irregular heart rhythm. This can go unnoticed throughout life, but also lead to sudden cardiac death, typically in patients between age 25-55. At present, more than 25 genes have been identified that can explain about 30% of BrS cases. The question remains why in the same family individuals with the identical genetic alteration can live without symptoms, have few or many arrhythmia episodes or even experience sudden death. I will look for an answer to this question in a group of families with a known error in the SCN5A gene causing BrS. I will study the exact effect of this genetic error and I will compare the difference in genetic signals between a selection of patients without symptoms and patients with severe symptoms, using whole genome and RNA sequencing techniques. Since it is important to work with heart cells in this study, I will use an advanced method that allows me to create heart cells from the patient's own skin or blood cells. Analysis of the genetic signals will lead us to the 'modifier genes' responsible for the differences in BrS disease severity. Identification of these modifiers will lead to a better insight into the mechanisms causing BrS, drive the development of novel therapies and result in more accurate risk prediction and personalized management of BrS patients."