protein breakdown begins in the digestive system of the human body.
protein breakdown begins in the digestive system of the human body.
where does protein breakdown begin in the human body?
digestive system
the highly acidic environment in the stomach lumen causes proteins from food to lose their characteristic folded structure (or denature). this exposes the protein's peptide bonds. the gastric chief cells of the stomach secrete enzymes for protein breakdown (inactive pepsinogen, and in infancy rennin). hydrochloric acid activates pepsinogen into the enzyme pepsin, which then helps digestion by breaking the bonds linking amino acids, a process known as proteolysis. in addition, many microorganisms have their growth inhibited by such an acidic environment, which is helpful to prevent infection.









































section::::secretion.
gastric acid
resistance training and subsequent consumption of a protein-rich meal promotes muscle hypertrophy and gains in muscle strength by stimulating myofibrillar muscle protein synthesis (mps) and inhibiting muscle protein breakdown (mpb). the stimulation of muscle protein synthesis by resistance training occurs via phosphorylation of the mechanistic target of rapamycin (mtor) and subsequent activation of mtorc1, which leads to protein biosynthesis in cellular ribosomes via phosphorylation of mtorc1's immediate targets (the p70s6 kinase and the translation repressor protein 4ebp1). the suppression of muscle protein breakdown following food consumption occurs primarily via increases in plasma insulin. similarly, increased muscle protein synthesis (via activation of mtorc1) and suppressed muscle protein breakdown (via insulin-independent mechanisms) has also been shown to occur following ingestion of β-hydroxy β-methylbutyric acid.
exercise