Protein Turnover Flashcards
protein catabolic signals:
- glucagon
- thyroid hormones
- glucocorticoids
- catecholamines
- cytokines
protein anabolic signals:
- insulin
- AAs
AA oxidation, gluconeogenesis, ureagenesis are active during both fed and starved states, why?
both are required for handling a surplus of AA in fed state + ensure energy production and N excretion in starved state
what is the role of AA oxidation, gluconeogenesis, and ureagenesis in the fed state
AA ox: excess AA oxidized for energy or converted to other metabolites
G: AAs used to maintain blood glucose between meals or in low-carb diets
U: removes excess N from dietary AA breakdown
what is the role of AA oxidation, gluconeogenesis, and ureagenesis in the starved state
AA ox: AA broken down from tissues to provide energy/precursors for gluconeogenesis
G: maintaining blood glucose when glycogen stores are depleted
U: excreting N from AA breakdown following catabolism for energy/gluconeogenesis
what AAs have reversible reactions
Ala, Glu, Gln
what AAs have irreversible reactions
essential AAs (branched + Thr, Lys)
rapid turnover = non-regulatory enzymes
slower turnover = regulatory enzymes
T or F
false, rapid = regulatory / slower = non-regulatory
what types of proteins have the slowest turnover
structural
inflammation/increase in imflammatory cytokines = muscle anabolism/building
T or F
false, inflammation = muscle catabolism/muscle wasting
increased glucocorticoids interfere with what kind of signaling
insulin signaling
mechanical stimulation = local muscle stress = increased protein synthesis
T or F
true, short term only maximal if sufficient energy/AA supply/exercise
how can decreased protein degradation + acute increase in protein synthesis be supported
ingestion of essential AAs, act as an AA store to sustain AA pool
what types of training are anabolic
hypoxia + resistance training
