title: Progranulin compensates for blocked IGF-1 signaling to promote myotube hypertrophy in C2C12 myoblasts via the PI3K/Akt/mTOR pathway.
abstract: It is well known that growth hormone (GH)-induced IGF-1 signaling plays a dominant role in postnatal muscle growth. Our previous studies have identified a growth factor, progranulin (PGRN), that is co-induced with IGF-1 upon GH administration. This result prompted us to explore the function of PGRN and its association with IGF-1. In the present study, we demonstrated that, similar to IGF-1, PGRN can promote C2C12 myotube hypertrophy via the PI(3)K/Akt/mTOR pathway. Moreover, PGRN can rescue the muscle atrophy phenotypes in C2C12 myotube when IGF-1 signaling is blocked. This result shows that PGRN can substitute for IGF-1 signaling in the regulation of muscle growth. Our findings provide new insights into IGF-1-modulated complicated networks that regulate muscle growth.
authors.affiliation: Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung 912, Taiwan.
authors.forename: Shao-Yang
authors.initials: SY
authors.lastname: Hu
authors.forename: Chen-Chen
authors.initials: CC
authors.lastname: Tai
authors.forename: Yen-Hsing
authors.initials: YH
authors.lastname: Li
authors.forename: Jen-Leih
authors.initials: JL
authors.lastname: Wu
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers / Q000235:genetics; D000077155:Granulins; D006984:Hypertrophy; D007334:Insulin-Like Growth Factor I / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D008954:Models, Biological; D024510:Muscle Development / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000378:metabolism* / Q000473:pathology; D009133:Muscular Atrophy / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D032446:Myoblasts / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000077153:Progranulins; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism
chemical_list: D017931:DNA Primers; D000077155:Granulins; D007334:Insulin-Like Growth Factor I; D036341:Intercellular Signaling Peptides and Proteins; D019869:Phosphatidylinositol 3-Kinases; D000077153:Progranulins; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger; D058570:TOR Serine-Threonine Kinases; C120204:Grn protein, mouse; C546843:mTOR protein, mouse