will take place on Tuesday, March 1, 2016 from 17:15 to 18:15 in Lecture Hall H1.
Host: Prof. Hendrik Lehnert
Department of Internal Medicine I
Universität zu Lübeck
Abstract
Using incorporation of 14C from the atmosphere into DNA and lipids of human fat cells it is possible to determine the age of fat cells and their triglyceride content (the major lipid component of the fat cell lipid droplet). The average age of adult human fat cells is about 10 years and relative constant over the adult human life span. However, the turnover rate of fat cell is doubled among obese compared to non-obese. In spite of this fat cell number does not decrease following marked weight reduction. A low turnover of fat cell is associated with a pernicious adipose morphology (few but large fat cells), which is subjects to genetic regulation. Low fat cell levels of a transcription factor, EBF1, causes this morphology and is accompanied by insulin resistance and altered fat cell lipid metabolism. A major source of renewal of human fat cells is the bone marrow. In obese up to 20% of all fat cells are derived from this source. There is also a high turnover of the fat cell triglycerides. During 10-year the life span of an adult fat cell its lipids are renewed 6 times. Lipid turnover is decreased in obesity due to a combination of increased storage capacity and decreased removal capacity of fat cell triglycerides. In a common hereditary dyslipidemia, familial combined dyslipidemia, the turnover of fat cell triglycerides is also decreased and, in the general population, there is a strong correlation between dyslipidemia and low turnover of fat cell triglycerides. The findings above will be reviewed in detail and also information about novel preliminary findings about triglyceride turnover in human adipose tissue will be discussed.
CV
Peter Arner studied medicine at Karolinska Institutet and became a licensed physician in 1970. He was clinically trained at the Karolinska University Hospital Huddinge and became a specialist in internal medicine in 1976 and in endocrinology 1980. He worked as a postdoctoral fellow at University of Rochester, NY, USA from 1980 to 1982. He is currently Deputy Chairman of the Diabetes Research Program at Karolinska Institutet. Peter Arner has primarily worked with experimental and clinical research on how fat metabolism is regulated in humans and is especially interested in fat tissue function. He has studied how fat cells and their genes control this at the molecular level, in both healthy and sick people, and the role adipose tissue plays in order to develop diabetes and atherosclerosis. His research group has shown, for instance, that fat cells are formed throughout life and not just in childhood. Proferssor Arner is well recognized for his work with numerous prestigious awards, e.g. Wasserman Award in Obesity Research in 2005, Eric K. Fernström Nordic Award in Medicine in 2012 and Esko Nikkkilä International Award in Medicine in 2014.
