Abstract
Background. Both fasting and ageing processes lead to muscle wasting. We studied the effect of single 48 h fasting on soleus skeletal muscle mass and force in young and old mice.Methods. The study involved 18 young and 13 old mice. Body and soleus (SOL) muscle mass were measured followed by assessment of peak and specific SOL force under ex vivo conditions. SOL muscle half-relaxation time and 20 Hz to 100 Hz force ratio were also measured.Results. After fasting, weight loss was greater (p < .05) in young mice compared to old mice (17.0 ± 2.6 versus 12.0 ± 1.7%, respectively). Fasted young, but not old mice showed reduction (p < .05) in SOL mass compared to the control values. On the other hand, specific SOL force was reduced (p < .05) only in old mice, while 20 Hz to 100 Hz force ratio decreased (p < .05) only in young mice after fasting.Conclusions. Our results showed that 48 h fasting caused lower SOL muscle peak and specific force in old but not young mice. Keywords: starvation, peak force, specific force, ageing.
Highlights
Periodic fasting or restriction of the exogenous nutrient intake is a popular strategy to limit energy intake and improve health (Longo & Mattson, 2014)
Our results showed that 48 h fasting caused lower SOL muscle peak and specific force in old but not young mice
These changes are associated with imbalance between protein breakdown and synthesis, which are key determinants of muscle mass (Bowen, Schuler, & Adams, 2015)
Summary
Periodic fasting or restriction of the exogenous nutrient intake is a popular strategy to limit energy intake and improve health (Longo & Mattson, 2014). It is not surprising that skeletal muscle is highly sensitive to fasting which is reflected in activation of FoxO transcription factors leading to increased capacity of proteolysis pathways even after relatively short periods of fasting (Egerman & Glass, 2014) These changes are associated with imbalance between protein breakdown and synthesis, which are key determinants of muscle mass (Bowen, Schuler, & Adams, 2015). Food intake of older persons in their seventies decreases by nearly 30% compared to the intake of younger persons in their twenties (Morley, 2017) Both malnutrition and ageing processes act synergistically to promote muscle wasting and further compound elderly to the poorest quality of life and prognosis (Morley, 2017). We studied the effect of single 48 h fasting on soleus skeletal muscle mass and force in young and old mice
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
