Abstract |
The c-Jun N-terminal kinase (JNK) pathway is known to be activated under diabetic conditions and to possibly be involved in the progression of insulin resistance. In this study, we examined the effects of modulation of the JNK pathway in liver on insulin resistance and glucose tolerance. Overexpression of dominant-negative type JNK in the liver of obese diabetic mice dramatically improved insulin resistance and markedly decreased blood glucose levels. Conversely, expression of wild type JNK in the liver of normal mice decreased insulin sensitivity. The phosphorylation state of crucial molecules for insulin signaling was altered upon modification of the JNK pathway. Furthermore, suppression of the JNK pathway resulted in a dramatic decrease in the expression levels of the key gluconeogenic enzymes, and endogenous hepatic glucose production was also greatly reduced. Similar effects were observed in high fat, high sucrose diet-induced diabetic mice. Taken together, these findings suggest that suppression of the JNK pathway in liver exerts greatly beneficial effects on insulin resistance status and glucose tolerance in both genetic and dietary models of diabetes.
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Authors | Yoshihisa Nakatani, Hideaki Kaneto, Dan Kawamori, Masahiro Hatazaki, Takeshi Miyatsuka, Taka-Aki Matsuoka, Yoshitaka Kajimoto, Munehide Matsuhisa, Yoshimitsu Yamasaki, Masatsugu Hori |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 279
Issue 44
Pg. 45803-9
(Oct 29 2004)
ISSN: 0021-9258 [Print] United States |
PMID | 15331609
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Dietary Fats
- Insulin Receptor Substrate Proteins
- Irs1 protein, mouse
- Phosphoproteins
- Sucrose
- JNK Mitogen-Activated Protein Kinases
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Topics |
- Animals
- Dietary Fats
(administration & dosage)
- Glucose Tolerance Test
- Insulin Receptor Substrate Proteins
- Insulin Resistance
- JNK Mitogen-Activated Protein Kinases
(physiology)
- Liver
(metabolism)
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- Phosphoproteins
(metabolism)
- Phosphorylation
- Sucrose
(administration & dosage)
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