Phytoecdysteroids - National Strength and …€¦ · Protein Synthesis vs. Protein Degradation •...
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Transcript of Phytoecdysteroids - National Strength and …€¦ · Protein Synthesis vs. Protein Degradation •...
Phytoecdysteroids: Implications for Muscle Recovery and
Enhanced Sports Performance
Kevin A. Zwetsloot, Ph.D. Integrative Muscle Physiology Laboratory
Appalachian State University
Learning Objectives
1. Describe the processes involved in skeletal muscle growth, injury, and repair
2. Understand the benefits of naturally‐occurring plant steroids to aid in skeletal muscle growth, repair, and injury
Importance of Skeletal Muscle
• Comprises ~40% of total body mass– required for movement and locomotion
• Muscle mass is an important determinant of muscle function– physiological cross‐sectional area is correlated to peak isometric force (Gans 1982 and Sacks and Roy 1982)
Protein Synthesis vs. Protein Degradation
• The maintenance of skeletal muscle mass exists as a delicate balance between the rates of muscle protein synthesis and muscle protein degradation
Synthesis Degradation
Protein Synthesis vs. Protein Degradation
• The maintenance of skeletal muscle mass exists as a delicate balance between the rates of muscle protein synthesis and muscle protein degradation Conservation of Muscle Mass
Skeletal Muscle Protein Synthesis
Skeletal Muscle Protein Degradation
Normal Activity
Protein Synthesis vs. Protein Degradation
• The maintenance of skeletal muscle mass exists as a delicate balance between the rates of muscle protein synthesis and muscle protein degradation Gain of Muscle Mass (Hypertrophy)
Skeletal Muscle Protein Synthesis
Skeletal Muscle Protein Degradation
Heavy Loading/Repair
Protein Synthesis vs. Protein Degradation
• The maintenance of skeletal muscle mass exists as a delicate balance between the rates of muscle protein synthesis and muscle protein degradation Loss of Muscle Mass (Atrophy)
Skeletal Muscle Protein Synthesis Skeletal Muscle
Protein Degradation
Unloading/Disuse
Muscle Protein Synthesis: PI3k/Akt Pathway
Muscle Protein SynthesisHoppeler et al. 2011
Skeletal Muscle Injury
Urso 2013
Post‐Injury NSAID Treatment
Urso 2013
Phytoecdysteroids
• Found in high abundance in a variety of hardy plant species (Bathori et al. 2008)
• Traditional folk remedy used hardy plants to boost stamina and ward off illness
Phytoecdysteroids
• Contains an array of bioactive properties– Medicinal– Biological– Pharmacological
• Anabolic, but non‐androgenic properties
• No known side effects in mammals
20‐hydroxyecdysone (20E)
Toth et al. (2008)
Anabolic Properties of 20‐E• Increase protein synthesis 120% in C2C12 myotubes
• Works through PI3k‐Akt– Independent of traditional steroid receptor pathway
• Increase strength 18% in young rats fed for 28 daysGorelick‐Feldman et al. 2008
Take Home Messages
• Phytoecdysteroids are natural plant steroids that possess anabolic, but non‐androgenic properties
• Phytoecdysteroids increase signaling mechanisms leading to protein synthesis
• Phytoecdysteroids may enhance skeletal muscle repair after injury