Open AccessHeat induces myogenic transcription factors of myoblast cells via transient receptor potential vanilloid 1 (Trpv1)
Author(s) -
Obi Syotaro,
Nakajima Toshiaki,
Hasegawa Takaaki,
Nakamura Fumitaka,
Sakuma Masashi,
Toyoda Shigeru,
Tei Chuwa,
Inoue Teruo
Publication year - 2019
Publication title -
febs open bio
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.718
H-Index - 31
ISSN - 2211-5463
DOI - 10.1002/2211-5463.12550
Subject(s) - hsf1 , microbiology and biotechnology , trpv1 , protein kinase b , transient receptor potential channel , heat shock factor , pi3k/akt/mtor pathway , myocyte , chemistry , phosphorylation , heat shock , heat shock protein , biology , hsp70 , signal transduction , biochemistry , receptor , gene
Exercise generates heat, blood flow, and metabolic changes, thereby inducing hypertrophy of skeletal muscle cells. However, the mechanism by which heat incudes hypertrophy in response to heat is not well known. Here, we hypothesized that heat would induce differentiation of myoblast cells. We investigated the underlying mechanism by which myoblast cells respond to heat. When mouse myoblast cells were exposed to 42 °C for over 30 min, the phosphorylation level of protein kinase C ( PKC ) and heat shock factor 1 (Hsf1) increased, and the mRNA and protein expression level of heat shock protein 70 (Hsp70) increased. Inhibitors of transient receptor potential vanilloid 1 (Trpv1), calmodulin, PKC , and Hsf1, and the small interfering RNA‐mediated knockdown of Trpv1 diminished those heat responses. Heat exposure increased the phosphorylation levels of thymoma viral proto‐oncogene 1 (Akt), mammalian target of rapamycin ( mTOR ), eukaryotic translation initiation factor 4E binding protein 1 (Eif4ebp1), and ribosomal protein S6 kinase, polypeptide 1 (S6K1). The knockdown of Trpv1 decreased these heat‐induced responses. Antagonists of Hsp70 inhibited the phosphorylation level of Akt. Finally, heat increased the protein expression level of skeletal muscle markers such as myocyte enhancer factor 2D, myogenic factor 5, myogenic factor 6, and myogenic differentiation 1. Heat also increased myotube formation. Knockdown of Trpv1 diminished heat‐induced increases of those proteins and myotube formation. These results indicate that heat induces myogenic transcription factors of myoblast cells through the Trpv1, calmodulin, PKC , Hsf1, Hsp70, Akt, mTOR , Eif4ebp1, and S6K1 pathway. Moreover, heat increases myotube formation through Trpv1.