Molecular & Cellular Toxicology

The Korean Society of Toxicogenomics and Toxicoproteomics (대한독성유전 단백체학회)
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Eucommia ulmoides Extract Stimulates Glucose Uptake through PI 3-kinase Mediated Pathway in L6 Rat Skeletal Muscle Cells

  • Hong, Eui-Jae (Graduate School of East-West Medical Science, Kyung Hee University) ;
  • Hong, Seung-Jae (Kohwang Medical Research Institute, Kyung Hee University) ;
  • Jung, Kyung-Hee (Kohwang Medical Research Institute, Kyung Hee University) ;
  • Ban, Ju-Yeon (Kohwang Medical Research Institute, Kyung Hee University) ;
  • Baek, Yong-Hyeon (Department of Acupuncture & Moxibustion, East-West Neo Medical Center, Kyung Hee University) ;
  • Woo, Hyun-Su (Department of Acupuncture & Moxibustion, East-West Neo Medical Center, Kyung Hee University) ;
  • Park, Dong-Suk (Department of Acupuncture & Moxibustion, East-West Neo Medical Center, Kyung Hee University)
  • Published : 2008.09.30
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Abstract

Eucommia ulmoides (Duchung) is commonly used for treatment of diabetes in Korean traditional medicine. However, the exact mechanism of its anti-diabetic effect has not yet been fully elucidated. In this study, the effect of E. ulmoides extract on glucose uptake was investigated in L6 rat skeletal muscle cells. E. ulmoides extract stimulated the activity of phosphatidylinositol (PI) 3-kinase that is a major regulatory molecule in glucose uptake pathway. Protein kinase B (PKB) and protein kinase C-${\xi}$ (PKC-${\xi}$), downstream mediators of PI 3-kinase, were also activated by E. ulmoides extract. We assessed the activity of AMP-activated protein kinase (AMPK), another regulatory molecule in glucose uptake pathway. Phosphorylation level of AMPK did not change with treatment of E. ulmoides extract. Phosphorylations of p38 mitogen activated protein kinase (p38 MAPK) and acetyl-CoA carboxylase (ACC), downstream mediators of AMPK, were not significantly different. Taken together, our results suggest that E. ulmoides may stimulate glucose uptake through PI 3-kinase but not AMPK in L6 skeletal muscle cells.

Keywords

References

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