Flashcards in Starvation and Malnutrition Deck (17)
How does your body get its energy in the fed state?
glycolysis, aerobic respiration
How does your body get its energy fasting b/w meals?
4-6 hours gluconeogenesis begins
glycogenolysis persists until 10-18 hours after meal
a little bit of FFA release from adipose tissue
**glucagon and epinephrine stimulate
What is the main source of energy after fasting 1-3 days?
also get some glucose (solely from gluconeogenesis) and ketone bodies
Starving after 5 days, what is the main energy source?
also some glucose and fatty acids
Once again, when are the glycogen stores depleted?
after 1 day
really after 10-18 hours
Main source of energy for brain and muscles:
1 day of fasting
2 days of fasting
5 days of fasting
1 day of fasting: brain-glucose, muscles--mainly fatty acids, some glucose
2 days of fasting: brain-glucose, some ketone bodies, muscles--mainly fatty acids, some ketones
5 days of fasting: brain-ketone bodies, muscle--mainly fatty acids, some ketone bodies
Once again, when does the ketone body formation begin?
after 2 days of fasting
What is the one part of the body that can't use ketones?
RBCs, lack mitochondria
Describe the circumstances that favor ketone formation?
oxaloacetate has been all used up b/c of gluconeogenesis
so now acetyl CoA can't enter TCA. Instead, it goes on to make ketone bodies.
Acetyl CoA increases b/c of beta oxidation of fatty acids
Fatty Acids and amino acids-->acetoacetate + beta hydroxybutyrate
Rate limiting enzyme: HMG CoA synthase
What type of ketone does the urine test detect?
only detects acetoacetate
Why does a patient in diabetic ketoacidosis have fruity breath?
b/c of acetoacetate-->acetone (fruity smell)
Why does EtoH on an empty stomach set you up for fasting hypoglycemia?
b/c alcohol causes the formation of NADH.
the increase in NADH favors the formation of pyruvate-->lactate and oxaloacetate-->malate
these then can't be used for gluconeogenesis.
Basically, the liver can only metabolized ETOH or give body glucose. not both. Fasting hypoglycemia.
What are 4 possible fates of acetyl CoA?
Fatty acid synthesis
What are the important features of kwashiorkor?
fatty liver (b/c of lack of ApoB100)
malnutrition (of protein, may have adequate calories)
Edema (distended abdomen)
Skin lesions and depigmentation of hair and skin
What are the key features of marasmus?
totally energy malnutrition
also get variable edema, and loss of subcutaneous fat