Atrophy Flashcards
What are some common causes of atrophy
- inactivity
- aging
- malnutrition
- neuro conditions
- chronic conditions
- injury/surgery
what are some symptoms of muscle atrophy?
- muscle weakness
- decreased muscle mass
- fatigue
- difficulty moving
- balance issues
- joint pain
what are some risk factors for atrophy
- age
- sedentary lifestyle
- chronic disease
- neuro disease
- poor nutrition
T or F: with atrophy, both myofiber size and muscle quality is reduced
T
what are mechanisms of initiating muscle atrophy
- cortical steroids
- FOXO
- cytokines
- myostatin
what are some mechanisms to mitigate muscle atrophy
- anabolic steroids
- growth factors
- exercise stimulus
- follistatin (sequesters myostatin and inhibits it)
what are some inflammatory cytokines
IL-6
TNF-a
IL-1
what are some cytokine-like inflammatory markers
- HMGB1
- S100
- myostatin
what is HMBG1
an immune response modulator
what happens if you don’t have a myostatin gene? is this a viable therapy?
- lack of myostatin gene increases muscle mass but altering it to prevent muscle loss does not work well
what are 2 ways proteins can be recycled?
proteasome system
autophagy via lysosome
explain the ubiquitin system
- attaches to protein to signal
- 4+ tags = target for degradation
_________ expedites the wasting of skeletal muscle by selectively targeting and degrading sarcomeric proteins through the ubiquitin-proteasome pathway
MuRF1
MuRF1 expedites the wasting of skeletal muscle by selectively targeting and degrading sarcomeric proteins through the ______________ pathway
ubiquitin-proteasome
what’s another word for MAFbx
Atrogin
