Antidiabetic effect of nepodin, a component of Rumex roots, and its modes of action in vitro and in vivo. (23rd April 2014)

• Record Type: Journal Article
• Authors: Ha, Byung Geun; Yonezawa, Takayuki; Son, Myoung Jin; Woo, Je Tae; Ohba, Shinsuke; Chung, Ung‐Il; Yagasaki, Kazumi
• Is Part Of: BioFactors. Volume 40:Number 4(2014:Jul./Aug.)
• Page Start: 436
• Page End: 447
• Publication Date: 2014-04-23
• Subjects: Vitamins -- Physiological effect -- Periodicals; Trace elements -- Physiological effect -- Periodicals; Growth factors -- Physiological effect -- Periodicals; Plant growth promoting substances -- Physiological effect -- Periodicals; Biochemistry -- Periodicals; Nutritional Physiological Phenomena -- Periodicals; Trace Elements -- metabolism -- Periodicals; Vitamins -- metabolism -- Periodicals; Molecular Biology -- Periodicals; 612.399
• DOI: 10.1002/biof.1165
• Languages: English
• ISSNs: 0951-6433

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Many active components derived from edible natural resources such as plant extracts have recently attracted attention for their potential use as functional foods or drugs for preventing and treating metabolic diseases such as diabetes. To obtain a novel modulator of glucose metabolism, we conducted screening of a small compound library in cultured L6 myotubes. We identified nepodin that stimulated glucose uptake dose‐dependently in differentiated L6 myotubes. The stimulatory effect of nepodin on glucose uptake was abrogated by a 5′‐adenosine monophosphate‐activated protein kinase (AMPK) inhibitor. In addition, nepodin stimulated the phosphorylation of AMPK. Nepodin also stimulated the translocation of GLUT4 to the plasma membrane in L6 myoblasts transfected with a Glut4 cDNA‐coding vector and in differentiated L6 myotubes. In <italic>in vivo</italic> study, nepodin suppressed the increases in fasting blood glucose levels and improved the glucose intolerance of C57BL/KsJ‐<italic>db/db</italic> mice, a type 2 diabetic animal model. Nepodin rescued the impaired phosphorylation of AMPK in the skeletal muscle of <italic>db/db</italic> mice. These results suggest that nepodin has an antidiabetic effect, which is at least partly mediated by stimulation of GLUT4 translocation via AMPK activation by nepodin. © 2014 BioFactors, 40(4):436–447, 2014</p> </abstract>