Several inter‐organ networks have been proposed. In general, gastrointestinal hormone gastric inhibitory polypeptide (GIP), which is synthesized in and secreted from K cells, regulates nutrient absorption via inhibition of gastric contraction and acid secretion. GIP receptor On the other hand, GIPR expresses in not only a gastrointestinal tract but also β cells in the pancreas. Since GIP also modulates glucose metabolism via insulin synthesis and secretion, GIP is also a member of incretin. Recently, the expression of GIP is also confirmed in skeletal muscle. However, there is no evidence for the inter‐organ network between gastrointestine and skeletal muscle. In the present study, we investigated a physiological role of the inter‐organ network between gastrointestine and skeletal muscle via GIP. GIP stimulates myogenic differentiation of C2C12 cells. Expression of GIPR was observed in C2C12 myoblasts and myotubes. Knockdown of GIPR induced the down‐regulation of Pax7 in C2C12 myoblasts. In addition, GIPR‐knockdown‐associated depression of myotube formation of C2C12 cells were observed. On the other hand, GIPR‐knockdown stimulated proliferation of C2C12 myoblasts. Therefore, GIP‐GIPR intracellular signal(s) might play a role in the regulation of skeletal muscle volume via the mediation of myogenic differentiative potential.Support or Funding InformationThis study was supported, in part, by Grants‐in‐Aid for Challenging Exploratory Research (16K13022), and Grants‐in‐Aid for Scientific Research (17K01762, 18H03160) from the Japan Society for the Promotion of Science, the Descente Sports Foundation, the All Japan Coffee Association, the Science Research Promotion Fund from Promotion and Mutual Aid Corporation for Private Schools of Japan, and the research grants from Graduate School of Health Sciences, Toyohashi SOZO University.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
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