33 - Integration of Metabolism Flashcards
***Study the 3 main decisions (Slides 4-6)
Study 5 minutes
What are the fuel reserves of the muscle?
Glycogen
Protein
What are the energy pathways of the muscle?
Beta-oxidation
Glycolysis
Proteolysis
Citric acid cycle
What are the fuel reserves of the liver?
Triacylglycerols
Glycogen
What are the energy pathways of the liver?
Glycolysis
Gluconeogenesis
Beta-oxidation
Fatty acid synthesis
What are the fuel reserves the brain?
None
What are the energy pathways of the brain?
Glycolysis
Citric acid cycle
What are the fuel reserves of the heart?
None
What are the energy pathways of the heart?
Beta-oxidation
Citric acid cycle
What are the fuel reserves of the adipose tissue?
Triacylglycerols
What are the energy pathways of the adipose tissue?
Beta-oxidation
Triacylglycerol synthesis
What is the preferred fuel of the brain? During starvation?
Glucose
Ketone bodies
What is the preferred fuel of the skeletal muscle at rest?
Fatty acids
What is the preferred fuel of the skeletal muscle during exertion?
Glucose
What are the fuel producers?
1) Liver (glucose)
2) Adipocytes (fatty acids)
3) Kidneys (glucose – during starvation only)
What are the fuel consumers?
1) Skeletal muscle (glycogen – creatine phosphate – lactate)
2) Brain (glucose – ketone bodies)
3) Heart (fatty acids – lactate/ketone bodies)
The liver can store a day’s worth of fuel as ________, and its primary fuel is _______ _______, not glucose.
Glycogen
Fatty acids
In the liver during the fed state, there is an (INCREASE/DECREASE) in available glucose. This means there is an increased reaction rate of ________ and synthesis of fatty acids/TAG occurs.
Increase
Glucokinase
In the liver during the starving state, there is an (INCREASE/DECREASE) in available glucose. This means there is a decreased reaction rate of ________ and synthesis of ketone bodies occurs.
Decrease
Glucokinase
Glucokinase has a higher Km than _________ (vmax and saturation).
Hexokinase
Along with kidneys, the only organ to contain G6P (ability to “finish” gluconeogenesis) is the _______.
Liver
What are the only 2 organs that are able to convert back to glucose (gluconeogenesis).
Kidney
Liver
The liver lacks _________, meaning it can produce but not use ketone bodies.
CoA Transferase
Along with kidneys, the liver is the only organ to contain ______ cycle enzymes.
Urea
Alcohol consumption tips the balance. Metabolizing alcohol to acetate oxidizes 2 ______ to 2 ______.
NAD+
NADH
In ________ metabolization, less NAD+ means lowered gluconeogenesis, glycolysis, TCA cycle, Beta-oxidation and increased lactate + ketone bodies (acidosis) and TAG (fatty liver disease).
Alcohol
When we are _______, at the conclusion of the meal, influx of food stimulates energy production and storage.
Fed
When we are ________, greater than 1 hour after meal, preferred metabolic fuel stores are released for use.
Fasting
When we are ________, 4-5 days without food, shift to using fat stores (TAG) and derivatives (ketone bodies). Trying to prevent protein degradation.
Starving
With lipoproteins, the higher the density the more _______ there is than lipids.
Protein
What is the good lipoprotein? The bad?
HDL
LDL
If we have too much LDL in our body, _________ gets with ROS and oxidize LDLs. This makes them stick in vessels causing plaques.
Cholesterol
***Study slide 12
Study 5 minutes
_______ mimics starvation conditions.
Diabetes
In a normal response, insulin binding to insulin receptors activates downstream signaling pathways, leading to _______ uptake.
Glucose
In _______ diabetes, insulin is not produced by the pancreas, and blood glucose levels are high.
Type I
In _______ diabetes, insulin receptors do not activate downstream signaling pathways, and blood glucose levels are high.
Type II
Metabolism enzyme regulators are ______ and ______, which are Serine/Threonine kinases with opposite functions.
AMPK
mTOR
This is a Serine/Threonine protein kinase that is off when the cell is in a fed state.
AMPK (AMP-Activated Protein Kinase)
AMPK is activated by increased ______, which signifies that energy charge of cell is low and ATP is low.
AMP
AMPK is inhibited by increased ______, which signifies that energy charge of the cell is high.
ATP
AMPK activates enzymes in energy-_______ (_______) pathways.
Producing
Catabolic
AMPK inactivates enzymes in energy-________ (_______) pathways.
Requiring
Anabolic
This is a Serine/Threonine protein kinase and is turned on when the cell is in a fed state.
mTOR (mammalian target of Rapamycin)
The activator of mTOR is…
Insulin
The inhibitor of mTOR is…
AMPK
mTOR activates enzymes in energy-_______ (_______) pathways.
Requiring
Anabolic
mTOR inactivates enzymes in energy-_______ (_______) pathways.
Producing
Catabolic
AMPK is heterotrimeric (3 peptide subunits). The ______ subunit has an N-terminus kinase domain and C-terminus is phosphorylated (by Threonine). The _______ subunit is the structural component. The _______ subunit binds 4 AMPs (allosteric site – if ATP binds then it’s inhibited).
Alpha
Beta
Gamma
AMPK activates PPARy Coactivator 1A, which is the same as _______.
PGC-1A
The function of _______ are to deacetylate lysine by using NAD+ as a redox sensor. It is activated when NAD+ is high and NADH is low, inactivated in the reverse.
Sirtuins
Sirtuins are important for PGC-1A because it deacetylates Lysine and leads to transcriptional activation. The end result is increased _________ in the liver and increased _______ _______ oxidation in skeletal muscle and heart.
Gluconeogenesis
Fatty acid
PPAR has ______ isozymes.
Four
This PPAR isozyme stimulates fatty acid oxidation in the liver and skeletal muscle.
PPAR-alpha
This PPAR isozyme stimulates lipid synthesis and improves insulin sensitivity in liver and adipose tissue.
PPAR-gamma
This PPAR isozyme increases rates of fatty acid oxidation and thermogenesis in adipose tissue and skeletal muscle. It stimulates flux through the pentose phosphate pathway.
PPAR-delta
This hormone signals the fed state to decrease blood glucose level, increase fuel storage, and increase cell growth and differentiation.
Insulin
This hormone signals the fasting state to increase glucose release from the liver, increase blood glucose levels, and increase ketone bodies as alternative fuel for the brain.
Glucagon
This hormone signals stress to increase glucose release from the liver, and increase blood glucose level.
Epinephrine
This hormone is released from the pancreas and is a blood glucose sensor. Its actions delineate the fed state.
Insulin
This hormone is released from adipocytes and is a TAG store sensor. Its actions delineate the full state.
Leptin
T/F. Leptin and insulin work in concert.
True
_______ and ________ are peptide hormones that signal the full state, like leptin. But, these hormones action is brief and leptin action is longer.
CCK (Cholecystokinins)
GLP1 (Glucagon-like Peptide 1)
_________ neurons disseminate fed/full signals from Leptin and Insulin.
Anorexigenic (reduces appetite)
_________ neurons disseminate hungry signals from Ghrelin, Adiponectin, and PYY 3-36.
Orexigenic (induces appetite)
This hormone is slow-acting, for periods of prolonged stress. It has tissue-specific actions and is a cholesterol derivative.
Cortisol
Cortisol induces adipocytes to release…
Fatty acids
Cortisol induces skeletal muscle to…
Protein degradation and export amino acids
Cortisol induces the liver to increase ________ _______ and thus increase _________.
Pyruvate carboxylase
Gluconeogenesis