Myostatin expression is regulated by underfeeding and neonatal programming in rats
Isabel Carneiro1, Tamara González, Miguel López
1Department of Physiology, School of Medicine, Instituto de Investigación Sanitaria, University of Santiago de Compostela, S. Francisco s/n, Santiago de Compostela, A Coruña, Spain.
Journal of Physiology and Biochemistry
|June 12, 2012
Summary
Neonatal food restriction programs long-lasting changes in muscle myostatin expression in rats. Adult nutritional status, however, does not significantly alter myostatin levels, suggesting early life nutrition is key.
Area of Science:
- Muscle physiology and developmental biology.
- Endocrinology and nutritional science.
Background:
- Conflicting reports exist on how nutritional status affects myostatin levels.
- Myostatin is a key regulator of muscle mass.
Purpose of the Study:
- To investigate the impact of different food deprivation patterns on muscle myostatin expression.
- To compare effects in neonatal versus adult rats.
Main Methods:
- Utilized a rat model with adjusted litter sizes to simulate neonatal underfeeding.
- Assessed myostatin mRNA and protein levels at various ages (24 and 60 days).
- Implemented short-term (7 days) and long-term (7 weeks) food restriction in adult rats, including leptin treatment.
Main Results:
- Neonatal underfeeding (large litters) led to decreased muscle myostatin mRNA and protein in rat pups.
- These myostatin changes persisted into adulthood (60 days) despite ad libitum feeding post-weaning.
- Adult rats subjected to food restriction or leptin treatment showed no significant changes in myostatin mRNA levels.
Conclusions:
- Nutritional status during neonatal life appears to program myostatin gene expression.
- Myostatin expression in adult rats is less sensitive to short-term or prolonged nutritional changes.
- Early life nutrition plays a critical role in long-term regulation of myostatin.
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