B5-054 Nutrition Metabolism II Flashcards
proportion of nutrient which the fraction of amount consumed that reaches the systemic circulation
bioavailability
fat soluble vitamins require […] for absorption
micelles
what minerals are reduced in untreated fat malabsorption?
2
Ca
Mg
where is B12 absorbed?
ileum
ileus resection
where is Mg absorbed?
distal small intestine and colon
iron deficiency increases the absorption of
non-heme iron
fat soluble vitamins
ADEK
absorption is dependent on incorporation into micelles
fat soluble vitamins
ADEK
[…] deficiency often looks like folate deficiency
B12
what causes B12 deficiency?
decreased absorption ability
(achlorhydria in elderly)
causes….
- pernicious anemia
- nerve degeneration
- parasthesia
- paralysis/death
B12 deficiency
achlorhydria in eldery typically causes […] deficiency
B12
intestinal transport of calcium is regulated by
1-25 dihydroxycholecalciferol
vitamin D
Fe3+ is reduced to Fe2+ by […] in the lumen
ascorbic acid
why is it important to monitor iron in CKD?
- kidney looses ability to transport erythropoietin
- need adequate iron to supply erythroid cells
- reactions that form a variety of cellular molecules
- energy requiring
anabolic
- CHO, protein, and fat oxidized to CO2 and H2O
- liberated electrons passed to O2 to make ATP
catabolic
in muscle and adipose, insulin stimulates the uptake of glucose via the translocation of
GLUT4
in adipose tissue, insulin increases FA uptake and TAG storage via upregulation of
lipoprotein lipase
in adipose tissue, insulin decreases lipolysis by downregulation of
hormone sensitive lipase
where is glucagon synthesized?
a cells of pancreas
when is glucagon secreted?
when circulating glucose is low
sometimes alanine
glucagon primary site of action
liver
increases cAMP levels in the cell
glucagon
what happens to glucose in the fed state?
liver takes it up and stores as glycogen or converts excess to FA
what happens to lipids in the fed state?
- packaged into chylomicrons (exogenous)
- packaged into VLDLs at liver (endogenous)
what happens to amino acids in the fed state?
processed in liver to make glycogen, fat, or sent to muscle
what provides the main source of glucose for the entire body in the early fasted state?
liver glycogen
[…] from muscle and RBCs becomes an important source of carbons for liver GNG
lactate
[…] is important to provide pyruvate for GNG
alanine cycle
glycogen stores are usually depleted by hour […] of fasting
24
how does the ESRD dialysis diet differ from the CKD diet?
fat soluble vitamins are too big to pass through dialyzer membrane
must be monitored carefully
[…] is limited in the CKD diet
protein
after fasting then consuming a large meal, the liver will replenish
glycogen stores
cleaves lactose to galactose and glucose
lactase
cleaves sucrose to fructose and glucose
sucrase
starches are digested by
pancreatic a-amylases
disaccharides
3
maltose
sucrose
lactose
converts glucose into pyruvate
glycolysis
anaerobic respiration
glycolysis
when does GNG become a major process for maintaining blood glucose?
18-20 hours of fasting
liver glycogen depletes about […] hours after fasting
30
insulin stimulates glucose transport into
adipose and skeletal muscle
