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Published on: June 3, 2018
Ghrelin stimulates myocyte development
Weizhen Zhang1, Lili Zhao, Michael W Mulholland
1Department of Surgery, University of Michigan Gastrointestinal Peptide Center, Ann Arbor, MI, USA. weizhenz@umich.edu
Summary
Ghrelin, a gastric hormone, significantly enhances muscle development (myogenesis) in mouse cells. Specific structural elements of ghrelin are crucial for this potent stimulatory effect on muscle cell differentiation.
Area of Science:
- Cell Biology
- Endocrinology
- Muscle Physiology
Background:
- Ghrelin, a peptide hormone primarily produced in the stomach, is known for its role in regulating appetite.
- Emerging evidence suggests ghrelin may influence cellular development beyond its endocrine functions.
- The potential role of ghrelin in mesenchymal cell differentiation, particularly myogenesis, remains largely unexplored.
Purpose of the Study:
- To investigate the effect of ghrelin on myogenesis in vitro.
- To determine if ghrelin promotes the differentiation of mouse myoblasts into myocytes.
- To identify key structural components of ghrelin essential for its myogenic activity.
Main Methods:
- Utilized the mouse myoblast cell line C2C12 for in vitro studies.
- Assessed myogenesis by measuring the myogenic index and MyoD expression.
- Quantified myosin heavy chain (MHC) protein levels via Western blotting.
- Investigated the role of specific ghrelin amino acid sequences through targeted mutations and deletions.
Main Results:
- Ghrelin significantly increased the differentiation of premyocytes into myocytes, with a marked rise in the myogenic index (42% vs. 16%).
- Western blotting confirmed elevated expression of MHC protein in ghrelin-expressing cells.
- Treatment with exogenous ghrelin (10(-7) M) led to increased MyoD expression.
- The stimulatory effect on myogenesis was abrogated by mutating the third amino acid (serine to alanine) or deleting the first nine amino acids of ghrelin.
Conclusions:
- Ghrelin acts as a potent stimulator of myogenesis in vitro.
- The N-terminal region and the third amino acid of ghrelin are critical for its myogenic effects.
- These findings highlight a novel role for ghrelin in muscle development and differentiation.
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