TY - JOUR
T1 - Role of hepatic STAT3 in brain-insulin action on hepatic glucose production
AU - Inoue, Hiroshi
AU - Ogawa, Wataru
AU - Asakawa, Akihiro
AU - Okamoto, Yasuo
AU - Nishizawa, Akihiko
AU - Matsumoto, Michihiro
AU - Teshigawara, Kiyoshi
AU - Matsuki, Yasushi
AU - Watanabe, Eijiro
AU - Hiramatsu, Ryuji
AU - Notohara, Kenji
AU - Katayose, Koji
AU - Okamura, Hitoshi
AU - Kahn, C. Ronald
AU - Noda, Tetsuo
AU - Takeda, Kiyoshi
AU - Akira, Shizuo
AU - Inui, Akio
AU - Kasuga, Masato
N1 - Funding Information:
We previously showed that STAT3 regulates the expression of gluconeogenic genes and thereby controls glucose production in the liver ( Inoue et al., 2004 ). Our present study revealed that hepatic STAT3 is activated by insulin action in the brain at postprandial states. This notion was supported by the inhibition of hepatic STAT3 phosphorylation in NIRKO mice after glucose administration and by the induction of STAT3 phosphorylation in response to ICV infusion of insulin in normal mice. Moreover, the suppression of glucose production induced by ICV infusion of insulin was attenuated in mice lacking STAT3 specifically in the liver. These results indicate that STAT3 is a hepatic effector of the brain-insulin action that leads to the inhibition of hepatic glucose production. Phosphorylation of STAT3 in the liver of NIRKO mice was markedly but not completely inhibited after glucose administration, suggesting that a mechanism independent of the brain-insulin action also contributes to postprandial activation of STAT3 in the liver. Such mechanisms remain to be elucidated.
Funding Information:
We thank D. LeRoith for Alb- Cre mice. This work was supported by grants from the Ministry of Education, Culture, Sports, Science, and Technology of Japan (MEXT) to M.K., W.O., and H.I.; a grant for the 21st Century COE Program “Center of Excellence for Signal Transduction Disease: Diabetes Mellitus as Model” from MEXT to M.K.; a grant for the Cooperative Link of Unique Science and Technology for Economy Revitalization (CLUSTER) from MEXT to M.K.; and a grant from Kanae Foundation for Life & Socio-medical Science to H.I.
PY - 2006/4
Y1 - 2006/4
N2 - STAT3 regulates glucose homeostasis by suppressing the expression of gluconeogenic genes in the liver. The mechanism by which hepatic STAT3 is regulated by nutritional or hormonal status has remained unknown, however. Here, we show that an increase in the plasma insulin concentration, achieved either by glucose administration or by intravenous insulin infusion, stimulates tyrosine phosphorylation of STAT3 in the liver. This effect of insulin was mediated by the hormone's effects in the brain, and the increase in hepatic IL-6 induced by the brain-insulin action is essential for the activation of STAT3. The inhibition of hepatic glucose production and of expression of gluconeogenic genes induced by intracerebral ventricular insulin infusion was impaired in mice with liver-specific STAT3 deficiency or in mice with IL-6 deficiency. These results thus indicate that IL-6-STAT3 signaling in the liver contributes to insulin action in the brain, leading to the suppression of hepatic glucose production.
AB - STAT3 regulates glucose homeostasis by suppressing the expression of gluconeogenic genes in the liver. The mechanism by which hepatic STAT3 is regulated by nutritional or hormonal status has remained unknown, however. Here, we show that an increase in the plasma insulin concentration, achieved either by glucose administration or by intravenous insulin infusion, stimulates tyrosine phosphorylation of STAT3 in the liver. This effect of insulin was mediated by the hormone's effects in the brain, and the increase in hepatic IL-6 induced by the brain-insulin action is essential for the activation of STAT3. The inhibition of hepatic glucose production and of expression of gluconeogenic genes induced by intracerebral ventricular insulin infusion was impaired in mice with liver-specific STAT3 deficiency or in mice with IL-6 deficiency. These results thus indicate that IL-6-STAT3 signaling in the liver contributes to insulin action in the brain, leading to the suppression of hepatic glucose production.
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U2 - 10.1016/j.cmet.2006.02.009
DO - 10.1016/j.cmet.2006.02.009
M3 - Article
C2 - 16581004
AN - SCOPUS:33645579324
VL - 3
SP - 267
EP - 275
JO - Cell Metabolism
JF - Cell Metabolism
SN - 1550-4131
IS - 4
ER -