WILLENDORF AWARD AW0001 Establishment of the concept of visceral fat syndrome and the discovery of adiponectin

Clinical studies in recent years have demonstrated that the extent of obesity does not necessarily determine the development of obesity-related diseases such as type2 diabetes, hyperlipidemia, hypertension, but fat distribution is a much more important determinant In 1983, we reported a method for fat analysis using CT scan which enabled us to analyze in intraabdominal adipose tissue, namely visceral fat as well as subcutaneous fat. Then we demonstrated that visceral fat accumulation correlated to the disturbance of lipid and glucose metabolism, insulin resistance, hypertension and cardiovascular disease in obese subjects and even in non-obese subjects. From these clinical studies, we proposed the concept of ‘visceral fat syndrome’ in which multiple risk factors cluster through visceral fat accumulation. Besides, this syndrome is designated to be a very atherogenic state. Visceral fat syndrome is corresponding to the concept of metabolic syndrome recently noted. In order to clarify the molecular mechanism why visceral fat accumulation correlates to plural common diseases and also directly to atherosclerosis, we started a project for the analysis of adipose tissue using random sequence of expressed genes in adipose tissues. We found unexpectedly that adipose tissue, especially visceral fat, expressed strongly the genes encoding secretory proteins most of which are important bioactive substances (named as adipocytokines). In addition to known adipocytokines, several novel adipose-specific genes were identified. Among them, a collagen-like protein encoded by an adipose most abundant gene (apM-1) is the most important novel adipocytokine which is named adiponectin. Adiponectin has anti-diabetic, anti-atherogenic, anti-oncogenic and anti-inflammatory properties and its plasma levels decreases with visceral fat accumulation, suggesting that this molecules may play a central role in the visceral fat syndrome or metabolic syndrome. In this lecture, I would like to present the importance of adiponectin together with other adipocytokines in lifestyle-related diseases relevant to visceral fat accumulation.