Exam 3 Ketone Body Metabolism

Front 1

fates of FAs in the liver:
-storage as triglycerides
-Kreb's/TCA cycle and ATP production
-... production
-cholesterol synthesis
-lipoprotein synthesis
-release of free fatty acids in blood (you complex FAs with albumin)

Back 1

ketone body

Front 2

when you fast or starve, you increase ... and decrease ...

Back 2

glucagon
insulin

Front 3

3 primary responses we will see within 1st days of starvation:
-liver cells will break down ... into ... (first 24 hours)
-adipose tissue undergoes ... (breaking down fat) releasing free fatty acids into blood for fuel
-liver ... fatty acids and synthesizes ... to release into blood for fuel

Back 3

glycogen
glucose
lypolysis
oxidizes
ketone bodies

Front 4

ketogenesis:
... deficiency (or increased glucagon) --> mobilize ... from adipose --> increase fats to ... --> increased uptake and ... of fats --> increased production of ...

Back 4

insulin
free fatty acids
liver
oxidation
ketone bodies

Front 5

during longterm starvation, which energy substrate continues to increase over a matter of weeks?

Back 5

ketone bodies

Front 6

during longterm starvation, glucose levels drop at first, and then is maintained at a pretty constant level due to ... (liver making glucose from fatty acids)

Back 6

gluconeogenesis

Front 7

during long term starvation, free fatty acids show a slight increase and then ...

Back 7

levels off

Front 8

in the morning before breakfast, ... levels are at their highest, and ... are at their lowest

Back 8

ketone
glucose

Front 9

the body quickly shuts off ... production once glucose is introduced in the diet

Back 9

ketone body

Front 10

while we sleep, ketone bodies are produced and used for ...

Back 10

fuel (energy)

Front 11

ketone bodies:
-products of partial ... of fatty acids
-derived directly from ...
-used for ... by various tissues

Back 11

beta-oxidation
acetyl CoA
energy

Front 12

what are the 3 ketone bodies found in the bloodstream?

Back 12

acetoacetic acid
3-hydroxybutanoic acid
acetone

Front 13

ketogenesis:
-results from ... acetyl CoA production through fatty acid oxidation (TCA cycle can't keep up)
-occurs in ...
-ketone bodies provide fuel source for ... and ... muscle
-provide a fuel source for neurons in the brain once ... is completely depleted

Back 13

excess
mitochondria
cardiac
skeletal
glucose

Front 14

synthesis of ketone bodies occurs only in the ... and only when the production of acetyl CoA exceeds the capacity of the ... to oxidize it

Back 14

liver
TCA cycle

Front 15

during fasting, the TCA cycle has low levels of ..., which causes the cycle to slow down

Back 15

oxaloacetate

Front 16

which ketone body is blown off in lungs and makes a very characteristic smell (like over-ripe apples) when ketone is over produced?

Back 16

acetone

Front 17

what enzyme is absolutely necessary to use (breakdown) ketone bodies for energy?

Back 17

succinyl CoA: acetoacetate CoA transferase

Front 18

oxidation (reverse of synthesis) of ketone bodies:
-succinyl CoA:acetoacetate CoA transferase is an enzyme that is not expressed by ... cells, so ... make ketone bodies but can't use them

Back 18

liver
hepatocytes

Front 19

the acetyl CoAs formed from oxidation of ketone bodies enter the ... to produce ATP

Back 19

TCA cycle

Front 20

what kind of amino acids are these?
-leucine, isoleucine, lysine, tryptophan, phenylalanine, tyrosine

Back 20

ketogenic amino acids

Front 21

ketogenic amino acids can be catabolized to what 3 things?

Back 21

acetyl CoA
acetoacetyl CoA
acetoacetate

Front 22

regulation of ketone body synthesis:
-anything that affects ... affects ketone body synthesis also.
-the difference is when ... of the TCA cycle is low, it stimulates the production of more ketone bodies

Back 22

fatty acid oxidation
oxaloacetate

Front 23

elevated levels of ketone bodies in the blood can result from extended periods of ..., high -..., low-... diets, fasting, starvation, diabetes

Back 23

exercise
fat
carb

Front 24

during short-term fasting, plasma concentration of different factors change in order to try to spare the breakdown of ...

Back 24

protein (muscle)

Front 25

during sustained fasting, fatty acids begin to increase in blood 3-4 hours after a meal and progressively ... (with fasting) up to approximately 2-3 days before ... off

Back 25

increase
leveling off

Front 26

during sustained fasting, blood levels of ketone bodies begin to increase after about # hours, however, their levels continue to ... steadily over several days (10-20 days) before leveling off

Back 26

4
rise

Front 27

the brain prefers ... as its energy source

Back 27

glucose

Front 28

the brain cannot use ... as fuels because they cannot cross the blood-brain barrier

Back 28

fatty acids

Front 29

after 2-3 days of starvation, ketone body levels are high enough in the blood to enable them to enter cells of the ... and be utilized by ... (as opposed to glucose)

Back 29

brain
neurons

Front 30

ketone bodies may supply as much as ... of the energy requirement of the brain during starvation

Back 30

2/3rds

Front 31

ketone bodies can also serve as major substrates for the biosynthesis of neonatal ... and amino acids (building of myelin sheaths)

Back 31

cerebral lipids

Front 32

use of ketone bodies spares ..., which can be used as a source of amino acid precursors for gluconeogenesis (prevents ... wasting )

Back 32

skeletal muscle protein
muscle

Front 33

diabetic ketoacidosis (DKA):
-results from a reduced supply of cellular ... (due to low insulin) and a concomitant increase in fatty acid ... (due to high glucagon)

-ketone body production exceeds ability of peripheral tissue to ... them

Back 33

glucose
oxidation

oxidize

Front 34

diabetic ketoacidosis (DKA):
-ketone bodies are acidic (pKa ~ 3.5) and can lower blood pH ("..." pH < 7.35)
-can affect protein ... and ...
-can impair ability of ... to bind O2

Back 34

acidosis
structure and function
hemoglobin

Front 35

DKA:
-excess ... blown off during respiration
-gives a characteristic smell of "over-ripe apples"
-ketone bodies excreted in urine (...) - can also give urine a characteristic odor

Back 35

acetone
ketonuria

Front 36

ketonuria:
-levels of excess ketone bodies must be extremely ... to develop this
-can result from diabetes, fasting, dieting, starvation, and eating ...

Back 36

high
disorders

Front 37

early symptoms of DKA:
-extreme ...
-constant ...
-extreme weight loss
-lethargy
-... smell to breath
-agitation, irritation, aggression, confusion
-muscle wasting

Back 37

thirst
urination
fruity

Front 38

late symptoms of DKA:
-loss of ...
-extreme weakness, lethargy, and apathy
-... (vomiting)
-abdominal pain
-flu-like symptoms
-confusion
-unconsciousness and coma

Back 38

appetite
emesis

Front 39

Ketogenic diets (diets that increase the production of ketone bodies):

-used to prevent or reduce ... in people with epilepsy
-diet high in ...(88%) and low in ...(10%) and ...(2%)
-mimics starvation and raises levels of ketone bodies in blood
-mechanism unknown

Back 39

seizures
fats
protein
carbohydrates

Front 40

which of the following tissues does not use ketone bodies as a fuel source?
-heart
-liver
-skeletal muscle
-brain

Back 40

liver