METABOLIC SYNDROME, ADIPONECTIN AND FAT ROS
Iichiro Shimomura1, Tohru Funahashi1, and Yuji Matsuzawa2
1Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan and
2Sumitomo Hospital, Osaka, Japan
The metabolic syndrome, a cluster of insulin resistance, elevated blood pressure, and atherogenic dyslipidemia, is a common basis of atherosclerosis. Accumulation of intra-abdominal visceral fat stands upstream of the metabolic syndrome. Adipose tissue expresses a variety of genes for bioactive secretory proteins conceptualized as adipocytokines. We discovered a novel adipose-specific protein named adiponectin from human fat cDNAs. Adiponectin circulates in the plasma and its serum level is decreased in visceral fat accumulation. Results of experimental and clinical researches have demonstrated that hypoadiponectinemia underlies the pathogenesis of multiple diseases related to visceral fat accumulation, including atherosclerosis, hypertension, cardiac failure, insulin resistance, diabetes, hepatic steatosis, inflammatory bowel disease, and cancers. Recently, we revealed fat-derived reactive oxygen species (fat ROS) as an upstream factor in the development of hypoadiponectinemia and metabolic syndrome. Intervention targeting visceral fat accumulation, hypoadiponectinemia and fat ROS should be the way to therapeutically tackle the metabolic syndrome. Biomed Rev 2006; 17: 1-10.
Key words: Adipocytokines, adiponectin, fat ROS, metabolic syndrome, visceral fat
Received 15 December 2006, received revised 21 December 2006, accepted 22 December 2006.
Correspondence and reprint request to Dr Iichiro Shimomura, Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, 2-2, Yamada-oka, Suita, Osaka, 565-0871, Japan. Tel: 81 6 6879 3732, Fax: 81 6 6879 3739