Muscle Protein Synthesis & Satellite Cell Flashcards
Increase muscle mass can help with…
strength
nitrogen balance
protein for immune system
How much is muscle synthesized/catabolized daily?
1-2%
If you want an anabolic (building) you need…
build protein or maintain (RT)
Net balance of breakdown and synthesis
Sources of AA
1) protein breakdown
2) blood
3) de novo synthesis
Myonuclear Domain Theory
Increasing the capacity of skeletal muscle to produce proteins
Myonuclei controls/governs area of cytoplasm, area within the cell that is regional to the nuclei for protein synthesis.
Increase in this in order to have increase protein synthesis as the cell increases.
Where do myonuclei originate?
Satellite cells!
Provides myonuclei, important for hypertrophy! In periphery of cell.
Satellite cells
Myogenic precursor cells, upon activation an proliferate and differentiate into myoblast
Myoblasts are myonuclei prior to fusion w/ existing muscle or to each other to form myotube
Myogenic Regulatory Factors
regulates muscle growth
What causes satellite cell activation?
Muscle disruption
What is released form the ECM to activate c-Met receptor on satellite cells?
HGF, hepatic growth factor
damages:
chemical
physical
exercise induce
Muscle disruption
Strong relationship between muscle damage/disruption, strength and IGF-1, myosynthetic chain
What fatigues quicker? 2B or 1
Type 2B
Benefits of 2B to 2A?
More oxidative, more protected.
Thickest order of fibers, which is more pre disposable to damage?
1>2A>2B
2B more predisposed
Types of factors that tim satellite cells
Immune
Motor
Vasculature
Autocrine Other
