TY - JOUR
T1 - The anorexigenic effects of metformin involve increases in hypothalamic leptin receptor expression
AU - Aubert, Grégory
AU - Mansuy, Virginie
AU - Voirol, Marie Jeanne
AU - Pellerin, Luc
AU - Pralong, François P.
N1 - Funding Information:
This work was supported by grants from the Swiss National Science Foundation ( 320000-112075 and 310000-122094 ) to FPP.
PY - 2011/3
Y1 - 2011/3
N2 - Metformin demonstrates anorectic effects in vivo and inhibits neuropeptide Y expression in cultured hypothalamic neurons. Here we investigated the mechanisms implicated in the modulation of feeding by metformin in animals rendered obese by long-term high-fat diet (diet-induced obesity [DIO]) and in animals resistant to obesity (diet resistant [DR]). Male Long-Evans rats were kept on normal chow feeding (controls) or on high-fat diet (DIO, DR) for 6 months. Afterward, rats were treated 14 days with metformin (75 mg/kg) or isotonic sodium chloride solution and killed. Energy efficiency, metabolic parameters, and gene expression were analyzed at the end of the high-fat diet period and after 14 days of metformin treatment. At the end of the high-fat diet period, despite higher leptin levels, DIO rats had higher levels of hypothalamic neuropeptide Y expression than DR or control rats, suggesting a central leptin resistance. In DIO but also in DR rats, metformin treatment induced significant reductions of food intake accompanied by decreases in body weight. Interestingly, the weight loss achieved by metformin was correlated with pretreatment plasma leptin levels. This effect was paralleled by a stimulation of the expression of the leptin receptor gene (ObRb) in the arcuate nucleus. These data identify the hypothalamic ObRb as a gene modulated after metformin treatment and suggest that the anorectic effects of the drug are potentially mediated via an increase in the central sensitivity to leptin. Thus, they provide a rationale for novel therapeutic approaches associating leptin and metformin in the treatment of obesity.
AB - Metformin demonstrates anorectic effects in vivo and inhibits neuropeptide Y expression in cultured hypothalamic neurons. Here we investigated the mechanisms implicated in the modulation of feeding by metformin in animals rendered obese by long-term high-fat diet (diet-induced obesity [DIO]) and in animals resistant to obesity (diet resistant [DR]). Male Long-Evans rats were kept on normal chow feeding (controls) or on high-fat diet (DIO, DR) for 6 months. Afterward, rats were treated 14 days with metformin (75 mg/kg) or isotonic sodium chloride solution and killed. Energy efficiency, metabolic parameters, and gene expression were analyzed at the end of the high-fat diet period and after 14 days of metformin treatment. At the end of the high-fat diet period, despite higher leptin levels, DIO rats had higher levels of hypothalamic neuropeptide Y expression than DR or control rats, suggesting a central leptin resistance. In DIO but also in DR rats, metformin treatment induced significant reductions of food intake accompanied by decreases in body weight. Interestingly, the weight loss achieved by metformin was correlated with pretreatment plasma leptin levels. This effect was paralleled by a stimulation of the expression of the leptin receptor gene (ObRb) in the arcuate nucleus. These data identify the hypothalamic ObRb as a gene modulated after metformin treatment and suggest that the anorectic effects of the drug are potentially mediated via an increase in the central sensitivity to leptin. Thus, they provide a rationale for novel therapeutic approaches associating leptin and metformin in the treatment of obesity.
UR - http://www.scopus.com/inward/record.url?scp=79951783938&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79951783938&partnerID=8YFLogxK
U2 - 10.1016/j.metabol.2010.02.007
DO - 10.1016/j.metabol.2010.02.007
M3 - Article
C2 - 20303124
AN - SCOPUS:79951783938
SN - 0026-0495
VL - 60
SP - 327
EP - 334
JO - Metabolism: clinical and experimental
JF - Metabolism: clinical and experimental
IS - 3
ER -