Leptin controls adipose tissue lipogenesis via central, STAT3-independent mechanisms.
Leptin (encoded by Lep) controls body weight by regulating food intake and fuel partitioning. Obesity is characterized by leptin resistance and increased endocannabinoid tone. Here we show that leptin infused into the mediobasal hypothalamus (MBH) of rats inhibits white adipose tissue (WAT) lipogenesis, which occurs independently of signal transducer and activator of transcription-3 (STAT3) signaling. Correspondingly, transgenic inactivation of STAT3 signaling by mutation of the leptin receptor (s/s mice) leads to reduced adipose mass compared to db/db mice (complete abrogation of leptin receptor signaling). Conversely, the ability of hypothalamic leptin to suppress WAT lipogenesis in rats is lost when hypothalamic phosphoinositide 3-kinase signaling is prevented or when sympathetic denervation of adipose tissue is performed. MBH leptin suppresses the endocannabinoid anandamide in WAT, and, when this suppression of endocannabinoid tone is prevented by systemic CB1 receptor activation, MBH leptin fails to suppress WAT lipogenesis. These data suggest that the increased endocannabinoid tone observed in obesity is linked to a failure of central leptin signaling to restrain peripheral endocannabinoids.
Buettner
Christoph
C
Department of Medicine, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1005, New York, New York 10029, USA. christoph.buettner@mssm.edu
Muse
Evan D
ED
Cheng
Andrew
A
Chen
Linghong
L
Scherer
Thomas
T
Pocai
Alessandro
A
Su
Kai
K
Cheng
Bob
B
Li
Xiasong
X
Harvey-White
Judith
J
Schwartz
Gary J
GJ
Kunos
George
G
Rossetti
Luciano
L
Buettner
Christoph
C
D052436:Adipose Tissue, White / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D063385:Cannabinoid Receptor Modulators / Q000032:analysis; D002395:Catecholamines / Q000032:analysis; D007031:Hypothalamus / Q000378:metabolism; D007262:Infusions, Intravenous; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000008:administration & dosage / Q000378:metabolism* / Q000502:physiology; D050155:Lipogenesis; D008297:Male; D008954:Models, Biological; D051381:Rats; D017207:Rats, Sprague-Dawley; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors
D001786:Blood Glucose; D063385:Cannabinoid Receptor Modulators; D002395:Catecholamines; D007328:Insulin; D020738:Leptin; D050796:STAT3 Transcription Factor