Insulin-like growth factor binding protein (IGFBP)-3 and IGFBP-5 mediate TGF-β- and myostatin-induced suppression of proliferation in porcine embryonic myogenic cell cultures

• Published in: Experimental cell research 2005-11, Vol.311 (1), p.167-176
• Main Authors: Kamanga-Sollo, E., Pampusch, M.S., White, M.E., Hathaway, M.R., Dayton, W.R.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal - pharmacology; Cell Proliferation - drug effects; Cells, Cultured; DNA - metabolism; Fetus; Humans; IGFBP-3; IGFBP-5; Insulin-Like Growth Factor Binding Protein 3 - physiology; Insulin-Like Growth Factor Binding Protein 5 - physiology; Muscle; Myoblasts - cytology; Myoblasts - drug effects; Myoblasts - metabolism; Myostatin; Phosphorylation; Proliferation; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; RNA, Messenger - metabolism; Smad; Smad2 Protein - metabolism; Swine; TGF-β; Transforming Growth Factor beta - pharmacology; Transforming Growth Factor beta1
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1016/j.yexcr.2005.09.003

We have previously shown that cultured porcine embryonic myogenic cells (PEMC) produce both insulin-like growth factor binding protein (IGFBP)-3 and IGFBP-5 and secrete these proteins into their media. Exogenously added recombinant porcine (rp) IGFBP-3 and rpIGFBP-5 act via IGF-dependent and IGF-independent mechanisms to suppress proliferation of PEMC cultures. Furthermore, immunoneutralization of endogenous IGFBP-3 and IGFBP-5 in the PEMC culture medium results in increased DNA synthesis rate suggesting that endogenous IGFBP-3 and IGFBP-5 suppress PEMC proliferation. TGF-β superfamily members myostatin and TGF-β 1 have also been shown to suppress proliferation of myogenic cells, and treatment of cultured PEMC with either TGF-β 1 or myostatin significantly ( P