Lactation Flashcards
what happens to hormone levels post-delivery?
decrease in progesterone and estrogen
sucking stimulus triggers what?
hormone cascade stimulated in the anterior pituitary gland to release prolactin, which stimulates the production of milk in the alveolar cells of the mammary gland
oxytocin released from posterior pituitary gland to contract the milk out
oxytocin role?
- bonding
- suppresses ovulation
- contracts the uterus to control blood loss after delivery
advantages of breastfeeding?
- jaw/tooth development
- bacteriologically safe & always fresh
- contains a variety of anti-infectious agents and immune cells
- nutritionally superior
- decreased risk of food allergy
- decreased risk of metabolic disorders
- decreased risk of asthma
compartments of milk
- micelles
- membrane-bound globules
- live cells
- protein and NPN compounds
- lipids
- vits, mins, trace elements
sources of milk components?
- maternal plasma
- alveolar cells
- other mammary cells in situ
what are the 3 phases of milk production?
- colostrum (first 5-7 days)
- transitional milk (7 days to 3-4 weeks)
- mature milk
describe the proportion of colostrum constituents
higher protein and mineral (Na, K, Cl) and lower energy, lactose, and fat content
describe the proportion of transitional milk constituents
less protein, more lactose and fat
describe the composition of mature milk
depends on the infant’s needs
immunological properties of human breast milk
- direct action against pathogens
- modulation of immune response
- promotion of growth/maturation of GI tract
why is it hard to replicate the immune benefits in baby formula
pasteurization; bovine milk is catered to…. cows
function of whey proteins?
- protect proteins by preserving their S-S bonds
- can bind to pathogens to inhibit their growth
- resistant to proteolysis
what antibodies are relevant in breast milk?
- IgA (most prevalent)
- IgM
- IgE
- IgG
what does IgA do?
- protects against many pathogens
- blocks whole food proteins from absorption by binding them (allergens)
- promotes the closure of leaky junctions
what is bifidus factor
N-containing CHO that promotes the growth of lactobacilli
what do lysozymes do
break down proteoglycans
how does lactoferrin have anti-infectious properties?
bacteria that eat your iron tend to be more pathogenic but lactoferrin says no u can’t have this
what do lactoperoxidases do?
kill streptococci and enteric bacteria
how are lipases anti-infectious?
FFA and MAG have antiviral properties
interferons:
inhibit intracellular viral replication
B12
binding protein
neutrophils
phagocytosis
macrophages
synthesize complement, lactoferrin, lysozymes ,and carry out phagocytosis
lymphocytes
synthesize secretory IgA and other Igs
fibronectin
increase phagocytosis
complement
promotes opsonization
growth factors in breast milk
- cortisol/thyroxine/insulin
- prostaglandins
- polyamines
the protein content of infant formula is (higher/lower) than breast milk
higher
why does milk have a higher concentration of calcium, magnesium, and phosphates?
presence of micelles
what is the early protein hypothesis?
infants fed formula consume more protein and oftentimes more calories, leading them to have higher risk for obesity/overweight
“metabolic programming”
whey:casein ratio? in human milk?
60:40 (ranges from 70:30 to 80:20 to 50:40)
advantages of breast milk over infant formula?
- better catered whey:casein
- more nucleotides
- better balance of essential AAs
- decreased risk of allergic rxns
- bovine has no lactoferrin
why is it beneficial to have more whey than casein?
casein is a slower protein to digest/whey is easier to absorb
whey is also anti-infectious
what bovine milk protein is linked to allergy?
B-lactoglobulin
also happens to be one of the most prominent proteins
significance of taurine in human breast milk?
- needed for bile acid conjugation
- putative neurotransmitter
- conditionally essential AA
describe the methionine content of human breast milk
lower content due to higher whey ratio. this is good because it’s the most cytotoxic amino acid
also bc cystathionase comes later in development, methionine can’t be converted to cysteine
describe the cysteine content of human breast milk
rich cysteine - cystathionase (makes cysteine) is late to develop so having it provided is good
describe the phenylalanine content of human breast milk
lower para-hydroxyphenylpyruvate oxidase (breakdown enzyme) is late to develop
excess can adversely affect CNS
describe the tyrosine content of human breast milk
lower; tyrosine aminotransferase (breakdown enzyme) is late to develop
excess can adversely affect CNS
how many infants are allergic to cow’s milk?
2-7.5%
signs of cow’s milk allergy?
- vomiting, nausea
- sneezing, wheezing, chronic cough
- dermatitis
- headaches
what happens regarding food protein permeability of the GI tract w/cow milk allergy?
increased
how are the allergens in cow’s milk managed?
commercial hydrolysis with enzymes
can you give an infant soy protein formula if they have a cow milk allergy?
likely not, there’s cross reactivity
what is Heiner’s Syndrome?
hypersensitivity to cow’s milk protein
- GI blood loss and iron deficiency anemia
- failure to thrive
