Biochem- starvation and malnutrition

Question 1

Post-absorptive period fuels produced/used

Answer 1

Produced: glucose from hepatic glycogenolysis and gluconeogenesis
Fatty acids from adipose tissue

Used: glucose by all

Question 2

Gluconeogenesis begin and when fully active

Answer 2

4-6 hours after last meal begins

fully active at 10-18 hours after last meal – glycogen stores depleted

Question 3

Fuel production and usage in early starvation (24 hours last meal)

Answer 3

Produced: glucose from gluconeogenesis
Fatty acids from adipose tissue

Used:
Brain: glucose – can used ketone bodies
Muscles and other tissues: some glucose, mostly fatty acids

Question 4

Fatty acid breakdown

Answer 4

FA -> acetoacetate – +NADH to NAD+ –> b-hydroxybutyrate

Ketone bodies

Urine test for ketones only detects acetoacetate, not b-hydroxylbutyrate

Question 5

Fuel production and usage in intermediate starvation (48 hrs after last meal)

Answer 5

Produced:
Glucose
Fatty acids
Ketone bodies from liver

Used:
Brain: mostly glucose, some ketone bodies
Muscles, other tissues: fatty acids, some ketone bodies

Question 6

Metabolic scenario favoring synthesis of ketone bodies

Answer 6

When production of acetyl CoA from b-oxidation of FA exceeds oxidative capacity of the TCA cycle

Question 7

Fuel production and usage in prolonged starvation (5 days after last meal)

Answer 7

Produced:
Glucose
Fatty acids
Ketone bodies

Used:
Brain: ketone bodies -> 2 acetyl CoA -> TCA cycle
Other tissues: fatty acids, some ketone bodies and glucose

Question 8

Overnight fast vs 3 day fast glucose to ketone body usage

Answer 8

Overnight: 90% glucose, 5% ketone body

3 day: 60% ketone body, 40% glucose

Question 9

Ethanol metabolism effect on gluconeogenesis

Answer 9

NAD+ regeneration by liver

When liver metabolizing ethanol it can’t perform gluconeogenesis -> severe fasting hypoglycemia when consume a lot of alcohol in a fasting state

Question 10

Fate of Aceytl CoA

Answer 10

TCA cycle
Fatty acid synthesis
Cholesterol synthesis
Ketone synthesis

Question 11

Refeeding syndrome

Answer 11

Negligible nutrient intake at least 5 days

Cells intracellular depleted

Eat -> nutrients pulled back into cells, drops serum levels of Mg2+, phosphate, K+
-> arrhythmias and neurological problems

monitor electrolytes closely
slow feeding

phosphorylate to keep in cells -> depletion of ATP

Question 12

Kwashiorkor

Answer 12

“FLAMES”

Fatty Liver disease – can’t make apoB100 -> lipid accumulation
Anemia
Malnutrition – protein
Edema – lack serum proteins
Skin lesion s- depigmetnaiton of skin and hair

Question 13

Marasmus

Answer 13

Total energy malnutrition
Muscle wasting
SQ fat loss
Edema