1. Department of Internal Medicine (K.M., D.F., M.B., K.K.), University of Leipzig, Leipzig D-04103, Germany
2. Department of Cell and Molecular Biology (J.M.), Karolinska Institute, Stockholm S-17177, Sweden
3. Division of Endocrinology, Diabetologia and Nephrology, Integrated Research and Treatment Center Adiposity Diseases (N.K.), University of Leipzig, Leipzig D-04103, Germany
4. Department of Medicine (R.E.W.), Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, The University of Chicago, Chicago, Illinois 60637
5. Universite Catholique de Louvain Medical School (M.-C.M.), Brussels B-1200, Belgium
6. Institut of Pathology and Neuropathology (K.W.S.), University of Duisburg-Essen, Essen D-45122, Germany
7. Interdisciplinary Center for Clinical Research (K.K.), University of Leipzig, Leipzig D-04103, Germany