15 mai 2014: Prof. Philipp Scherer
Thursday, May 15th 2014
Professor and Director
Touchstone Diabetes Center
University of Texas Southwestern Medical Center, Dallas
«Diabetes, Obesity and the Central Role of the Adipocyte
in Maintaining Systemic Homeostasis»
During the progression from the lean to the obese state, adipose tissue undergoes hyperplasia as well as hypertrophy in an attempt to cope with the increased demand for triglyceride storage. Even though adipose tissue as a whole seems to be a relatively static tissue containing many adipocytes that turn over slowly, these cells are embedded in an environment that can rapidly adapt to the needs of expanding and newly differentiating adipocytes. The extracellular matrix of adipose tissue faces unique challenges with respect to adjusting to the need for remodeling and expansion. In parallel, the vasculature has to adapt to altered requirements for nutrient and oxygen exchange. Changes during the expansion process also affect adipocyte-derived secretory factors (adipokines), such as adiponectin. Adiponectin promotes insulin sensitivity, decreases inflammation and promotes cell survival. Its levels are frequently downregulated in the obese state. We have recently demonstrated that adiponectin potently stimulates a ceramidase activity and enhances ceramide catabolism and formation of its anti-apoptotic metabolite – sphingosine-1-phosphate (S1P). Our observations suggest a novel role of adipocyte-derived factors that have beneficial systemic effects, with sphingolipid metabolism as its core upstream component.
Philipp Scherer is Professor and Director of the Touchstone Diabetes Center at the University of Texas Southwestern Medical Center in Dallas. Dr. Scherer received his Ph.D. degree from the University of Basel, Switzerland, followed by post-doctoral training the Whitehead Institute at MIT in Cambridge. In 1997, he joined the faculty of the Albert Einstein College of Medicine where he was a Professor for Cell Biology and Medicine. Throughout his career, he has maintained an interest in processes related to cellular and systemic energy homeostasis. During his Ph.D., he identified several components of the mitochondrial protein import machinery. While a post-doc, he identified adiponectin, one of the first secretory factors to be described that almost exclusively originate in adipose tissue and which is currently widely studied by many different research groups. Current efforts in his laboratory are focused on the identification and physiological characterization of novel proteins that serve as potential links between the adipocyte, liver, the pancreatic beta cell and the processes of whole body energy homeostasis, inflammation, cancer and cardiovascular disease. His research team aims to identify novel targets for pharmacological intervention and to further define the role of adipose tissue as an endocrine organ. Scherer has been on the faculty of UT Southwestern Medical Center since 2007 as a member of the Departments of Internal Medicine and Cell Biology. He holds the Gifford O. Touchstone Jr. and Randolph G. Touchstone Distinguished Chair in Diabetes Research and is a member of the Simmons Comprehensive Cancer Center.