Projects / Programmes
Identification of novel genes, microRNAs and innate immunity biomarkers for hypercholesterolemia
| Code |
Science |
Field |
Subfield |
| 3.07.00 |
Medical sciences |
Metabolic and hormonal disorders |
|
| Code |
Science |
Field |
| B000 |
Biomedical sciences |
|
| Code |
Science |
Field |
| 3.02 |
Medical and Health Sciences |
Clinical medicine |
hypercholesterolemia, genome wide association study (GWAS), prepubertal pediatric population, prognostic markers, miRNA, innate immunity, inflammatory response, inflammasome, cholesterol crystals, atherosclerosis
Researchers (18)
Organisations (3)
Abstract
This project proposal is aimed at providing new knowledge and develop novel strategies for the prevention and treatment for hypercholesterolemia and associated cardiovascular disease (CVD), a prime killer in developed as well as in developing countries.
OBJECTIVES
The first objective is to identify novel genetic factors and micro RNA (miRNA) biomarkers for hypercholesterolemia in prepubertal children. We propose to employ a so-called pooled-sample genome wide association study (GWAS) as a cost-effective alternative for filtering genetic variability. The underlying hypothesis is that our case DNA pool (children at the high-end of plasma cholesterol distribution) will contain more susceptibility alleles than the control pool. We will also search for blood miRNAs as potential non-invasive biomarkers for hypercholesterolemia and CVD in very early asymptomatic stages. We focus on the Slovenian children for which a whole-population cholesterol screening has been performed since 1995. This is a unique screening scheme worldwide and presents a powerful sampling base for the proposed studies. Additional advantage of studying prepubertal population is that co-morbidities (obesity, diabetes, metabolic syndrome etc.) have not yet developed, as is the case with adults, increasing the likelihood to identify primary genetic and environmental risk factors. Additionally, results obtained on paediatric population have more immediate clinical value as clinicians can more effectively follow up young patients and design early prevention or therapeutic steps.
Within the second objective, we aim to examine the same cohort of case-control children as in the first objective for exploring the link of hypercholesterolemia to innate immunity. Namely, recent studies in mouse models and adult human cells have clearly shown that cholesterol crystals activate a so-called second signalling pathway of innate immunity by activating NLRP3 inflammasome. This, in turn, contributes to chronic inflammation and atherosclerosis progression. It is not known, however, to what extent the inflammasome activation is already present in prepubertal hypercholesterolemic children and how to explore the knowledge about perturbations of this inflammatory pathway for potential novel treatment strategies. We hence aim to characterise peripheral monocytes (PBMC) and macrophages of prepubertal hypercholesterolemic children for various immunity parameters. We will also examine how innate immunity/inflammasome activation is correlated with early signs of nascent atherosclerosis assayed by carotid intima-media thickness and vascular function.
RESEARCH GROUP
We reckon that we chose the most experienced research groups in Slovenia, which should be able to successfully tackle implementation of proposed research. Coordinator (S. Horvat, Biotechnical faculty (Univ. of Ljubljana) has expertise in genetic linkage and miRNA analyses, T. Battelino (University Medical Centre) is a clinician and scientist in paediatric metabolic diseases, R. Jerala (National Institute of Chemistry) will provide expertise in innate immunity.
RELEVANCE.
The proposed research is within the general area of “functional studies for health”, a priority area of our Ministry for Science, Slovenian Research Agency and EU framework programmes. Our study has a potential to add useful predictive information for DNA based and blood-borne miRNA marker-based diagnostics of children at risk for CVD and provide information on candidates for more targeted therapeutic interventions. Proposed in vitro studies on human blood cells are complementary and can help to explain the link to inflammatory response in promoting atherosclerosis and open up novel strategies for treatments. We strongly believe that this integrative proposal should yield important insights of basic and applied research interest addressing disorders and diseases that present a major problem to the current and future health of all populations and health c
Significance for science
The importance of the research results of this project is defined mainly from three aspects: the contribution of new basic knowledge, the acquisition of new genetic resources and the development and introduction of new methods. PROGRESS IN BASIC RESEARCH: The main outcome of the reserach in the first module is the identification of novel genes that contribute to the complex pathogenesis of hypercholesterolaemia. In addition to the known monogenic mutations that cause hypercholesterolaemia, the results of the published genetic studies so far can explain a relatively small proportion of other hereditary factors for hypercholesterolaemia. The new genes, and therefore targets for further preclinical and clinical studies, contribute to a better understanding of the cumulative effect of hypercholesterolemic genes and serve as potential new drug development targets. With the results of the second set of experiments, we helped to advance the understanding of the role of innate immunity and the inflammatory response in the development of hypercholesterolemia, which can lead to cardiovascular disease. The results of module 2 experiments are an excellent basis for the study of mechanistic mechanisms of the role of cholesterol homeostasis in inflammatory processes of innate immunity. DEVELOPMENT OF GENETIC RESOURCES: Obtaining new genetic resources is one of the most important aspects of this project. In the first module, we managed to establish a comprehensive collection of DNA samples and clinical data of children with hypercholesterolaemia and healthy control subjects. Especially samples of randomly selected healthy pediatric controls are extremely valuable genetic sources, which are rare in children at the age of only five years on a global scale. In addition, we have obtained samples and data from parents that allow for the study of inheritance. In the second module, we succeeded in collecting and appropriately storing plasma and peripheral blood cells for further studies, which can be used in cell-based trials after defrosting. Thus, the research and monitoring of these patients can be continued during follow-up treatment and subsequently performed even more precise clinical studies with reference to cells or other collected tissue samples of the same patient prior to therapy. INTRODUCTION OF NEW METHODS: Despite the fact that GWAS studies in the last few years have been the main approach to investigate the genetic basis of human diseases, such a study in Slovenia has not yet been performed. The introduction of the GWAS method on pooled DNA samples, and in particular the development of computer programs and approaches to large-scale data analyses, represent an important step towards the advancement of clinical genetic research in Slovenia. The experiments and the optimized protocols described in the second module will enable further development of the use of cell models in genetic studies of human diseases and for the first time be combined with clinical research.
Significance for the country
IMMEDIATE AND INDIRECT EFFECTS OF THE RESULTS:The results of our studies in the first module (identification of new hypercholesterolemic genes) will allow an additional risk assessment of genetic factors for the development of hypercholesterolaemia specifically in the Slovenian population. Newly detected genetic markers will allow early detection of individuals with a higher risk of developing cardiovascular disease and atherosclerosis. On the basis of this, early prevention of disease development, individualized treatment and consequently improvement of the quality of life of patients and their relatives will be possible. In vitro and in vivo studies of the second module of experiments provide a new insight into the currently unknown mechanisms that link cholesterol metabolism and the immune system. These results are potentially useful in the development of new medicines for the treatment of cardiovascular diseases, such as atherosclerosis. The results of this project can therefore serve as a basis for future cooperation with Slovenian pharmaceutical companies aimed at finding new markers or inhibitors of early inflammatory processes of innate immunity and the development of more effective drugs for the treatment of hypercholesterolaemia and atherosclerosis with less side effects. In the long term, the results of our research will contribute to more effective detection and treatment of the consequences of hypercholesterolaemia. This will affect the prolongation of the active and productive working lives of patients with hypercholesterolaemia and consequently reduce the burden on the state health budget. PROMOTION OF SLOVENIAN SCIENCE:Development and application of new genetic resources (GWAS data, DNA and tissue collections, in vitro and in vivo models) in combination with new technologies ("omics") are of vital importance today in the advancement of clinical genetics and immunological sciences. Slovenia is internationally not recognizable in these areas, therefore we consider that the study is also important in terms of the progress of Slovenian science as well as the scientific visibility of Slovenia. EDUCATIONAL ASPECT: Within this research, two master's theses were completed and two doctoral students were included. Two of these are appropriately trained to design new research projects and lead new research in the area of cholesterol or metabolic diseases and innate immune responses.
Most important scientific results
Final report
Most important socioeconomically and culturally relevant results
Annual report
2014,
2015,
final report
