This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Fang, C.-H. Articles by Hasselgren, P.-O. Search for Related Content PubMed PubMed Citation Articles by Fang, C.-H. Articles by Hasselgren, P.-O. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB (L)-PHENYLALANINE COLCHICINE D-MANNITOL L-TYROSINE TRITIUM Medline Plus Health Information Burns Social Bookmarking                         What's this?

The Anabolic Effects of IGF-1 in Skeletal Muscle After Burn Injury Are not Caused by Increased Cell Volume

Department of Surgery, University of Cincinnati, and Shriners Hospital for Children, Cincinnati

Bing Guo Li, MD

Department of Surgery, University of Cincinnati, and Shriners Hospital for Children, Cincinnati

J. Howard James, PHD

Department of Surgery, University of Cincinnati, and Shriners Hospital for Children, Cincinnati

Josef E. Fischer, MD

Department of Surgery, University of Cincinnati, and Shriners Hospital for Children, Cincinnati

Per-Olof Hasselgren, MD

Department of Surgery, University of Cincinnati, and Shriners Hospital for Children, Cincinnati

Background: In a recent report, insulin-like growth factor 1 (IGF-1) stimulated protein synthesis and inhibited protein breakdown in skeletal muscle after burn injury. The mechanism of the anabolic effects of IGF-1 in skeletal muscle is not known. We tested the hypotheses that IGF-1 stimulates protein synthesis and inhibits protein breakdown in skeletal muscle secondary to cell swelling and that cell swelling in itself induces an anabolic response in muscle tissue. Methods: Extensor digitorum longus muscles from control and burned rats were incubated in the absence or presence of 1 µg/mL of IGF-1. Protein synthesis and breakdown rates were determined by measuring incorporation of ¹⁴C-phenylalanine into protein and net release of tyrosine, respectively. Cell volume was measured by determining wet and dry weight and by using ³H-mannitol as an extracellular marker. Results: IGF-1 stimulated protein synthesis and inhibited protein breakdown in muscles from nonburned and burned rats without influencing cell volume. Incubating muscles in hypo-osmotic medium increased cell volume by 17% and inhibited protein breakdown by 14% but did not influence protein synthesis. Conclusions: The anabolic effects of IGF-1 in skeletal muscle are not caused by increased cell volume. The results differ from those reported previously in liver cells in which the anabolic effects of IGF-1 were associated with cell swelling. The role of changes in cell volume in the regulation of protein metabolism may be different in skeletal muscle than in other tissues. (Journal of Parenteral and Enteral Nutrition 22:115-119, 1998)

Journal of Parenteral and Enteral Nutrition, Vol. 22, No. 3, 115-119 (1998)
DOI: 10.1177/0148607198022003115


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				C.-H. Fang, B.-G. Li, J. H. James, J.-K. King, A. R. Evenson, G. D. Warden, and P.-O. Hasselgren Protein Breakdown in Muscle from Burned Rats Is Blocked by Insulin-Like Growth Factor I and Glycogen Synthase Kinase-3{beta} Inhibitors Endocrinology, July 1, 2005; 146(7): 3141 - 3149. [Abstract] [Full Text] [PDF]

				L. J. Van Winkle Amino Acid Transport Regulation and Early Embryo Development Biol Reprod, January 1, 2001; 64(1): 1 - 12. [Abstract] [Full Text]

				T. Tashiro, T. Sugiura, Y. Morishima, N. Shimoda, H. Yamamori, K. Takagi, and N. Nakajima Effect of IGF-1 on Protein Metabolism in Burned Rats JPEN J Parenter Enteral Nutr, September 1, 1999; 23(5_suppl): S93 - S97. [Abstract] [PDF]

				C.-H. Fang, B.-G. Li, J. J. Wang, J. E. Fischer, and P.-O. Hasselgren Treatment of burned rats with insulin-like growth factor I inhibits the catabolic response in skeletal muscle Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1998; 275(4): R1091 - R1098. [Abstract] [Full Text] [PDF]