Aquaporin 7 deficiency is associated with development of obesity through activation of adipose glycerol kinase

Toshiyuki Hibuse, Norikazu Maeda, Tohru Funahashi, Kaori Yamamoto, Azumi Nagasawa, Wataru Mizunoya, Ken Kishida, Kazuo Inoue, Hiroshi Kuriyama, Tadashi Nakamura, Tohru Fushiki, Shinji Kihara, Iichiro Shimomura

Research output: Contribution to journalArticlepeer-review

212 Citations (Scopus)

Abstract

In adipocytes, hydrolysis of triglycerides results in the release of free fatty acids and glycerol. Aquaporin 7 (AQP7), a member of aquaglyceroporins, is known to permeabilize glycerol and water. We recently generated Aqp7-knockout (KO) mice and demonstrated that such mice have low plasma glycerol levels and impaired glycerol release in response to β3-adrenergic agonist, suggesting that AQP7 acts as a glycerol gateway molecule in adipocytes for the efficient release of glycerol in vivo. Although there was no difference in body weight between WT and KO mice until 10 weeks of age, here we found that KO mice developed adult-onset obesity. The body weight and fat mass increased significantly in KO mice compared with WT mice after 12 weeks of age. Adipocytes of KO mice were large and exhibited accumulation of triglycerides compared with WT mice. The KO mice developed obesity and insulin resistance even at a young age after consumption of high-fat/high-sucrose diet. We demonstrated the enhanced glycerol kinase enzymatic activity in Aqp7-KO and -knockdown adipocytes. A series of our results indicate that AQP7 disruption elevates adipose glycerol kinase activity, accelerates triglycerides synthesis in adipocytes, and, finally, develops obesity.

Original languageEnglish
Pages (from-to)10993-10998
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume102
Issue number31
DOIs
Publication statusPublished - Aug 2 2005

All Science Journal Classification (ASJC) codes

  • General

Fingerprint Dive into the research topics of 'Aquaporin 7 deficiency is associated with development of obesity through activation of adipose glycerol kinase'. Together they form a unique fingerprint.

Cite this