TN Metabolic Integration Flashcards
RLE for catecholamine synthesis
Tyrosine Hydroxylase
Co enzyme needed for dopa de-carboxylase
Pyridoxal Phosphate
End product of enzyme dopamine b oxidase
NorEpi
End product of enzyme PNMT
Epi
Formula for BMI
kg/m^2
Predominant hormone in WELL FED state
Insulin
What hormones maintain blood glucose levels during Starvation
Glucagon
Epi
Cortisol
GH
First 24h of starvation, what is responsible for maintaining blood glucose levels
Glycogen-o-lysis
After 24h of starvation, what process is mainly responsible for maintaining blood glucose levels
Gluco-neo-genesis
Substrates most commonly used for gluco-neo-genesis
Amino Acids
The only ketogenic amino acids
Lysine
Leucine
Both glucogenic and ketogenic amino acids
1) Phenylalanine,
2) Iso-leucine
3) Tyrosine
4) Tryptophan
5) Threonine
Major fuel of the body
Glucose
Fuel used by the heart, brain and muscle during prolonged starvation
Ketone bodies
2 predominant ketone bodies
Aceto-acetate
B-hydroxy-butyrate
Ketone detected predominantly in urine tests
Aceto-acetate
Organ responsible for ketogenesis
Liver
Immediate precursor of ketones
Acetyl CoA
The liver is able to make ketone bodies but cannot utilize them due to absence of this enzyme
Beta Keto Acyl CoA Transferase (or Thiophorase)
Muscle is unable to provide free glucose from glycogenolysis d/t lack of this enzyme
Glucose 6 phosphatase
Considered the major fuel reserve of the body
Adipose tissue
Triglycerides
Predominant hormone active during glycolysis
Insulin
Storage form of lipids in the body
Triglycerides
Which entities require constant glucose supply to function
CNS
RBCs
What are the glucose transporters in the Brain and RBC
GLUT 1 GLUT 3 (main for brain)
Glucose transporters for insulin-dependent tissues
GLUT 4
Muscle, Adipose, Pancreas
Insulin-dependent tissues
Muscle
Adipose
Pancreas
Major metabolic intermediate that can NEVER be used for gluco-neo-genesis
Acetyl CoA
Enzyme found in the liver that phosphorylates glucose for glycogen systhesis with high Km
Gluco-kinase
What is the net effect of insulin on the key enzymes of glycogen metabolism
Glycogen Phosphorylase is inhibited
Glycogen synthase is stimulated
Coenzyme needed by glycogen phosphorylase
Pyridoxal Phosphate
What is the net effect of insulin on the key enzymes of FA metabolism
Acetyl CoA Carboxylase is STIMULATED
Carnitine Palmitoyl Transferase 1 is INHIBITED
Overall effect of insulin on protein synthesis
INCREASE
Metabolic pathway in which lactate from ANAEROBIC metabolism in the muscle is converted to glucose in the liver and transported back to the muscle to be converted back into lactate
Cori Cycle
Metabolic pathway where muscles degrade amino acids for energy needs, the resulting nitrogen is trans-aminated to pyruvate to form ALANINE which is shuttled to the liver where the nitrogen enters the urea cycle and the pyruvate is used to make glucose and shunted back to muscle
Glucose Alanine Cycle
During prolonged fasting or starvation ketone bodies are utilized by the ff organs as a source of energy
Brain
Sk muscle
Heart
2 major organs responsible for gluco-neo-genesis
Liver
Kidneys
Main metabolic fuel source for the heart
Fatty acids
Example of a drug used for myocardial ischemia which switches cardiac metabolism to glucose by inhibiting FA oxidation
Trimetazidine
Usually the last source of fuel during a prolonged starvation phase
Protein/Amino acids
State of ketoacidosis accompanied by high glucose levels
DKA
State of ketoacidosis with HYPOglycemia
Alcoholism
Prolonged starvation
Pregnancy/Lactation
Which metabolic fuel provides carbon skeletons for triglyceride synthesis and non-essential amino acid synthesis
Glucose
Cellular organelle responsible for triglyceride synthesis and drug metabolism
Endoplasmic reticulum
Critical intermediate necessary to maintain TCA cycle activity usually depleted in prolonged starvation and alcohol intake
Oxalo-acetate
Net effect of starvation on adipose tissue enzymes
Inactivation of Lipo-protein lipase
+ Activation of Hormone sensitive lipase
–> Net release of Free FA
Prodominant hormone that has actions that are counter regulatory to insulin
Glucagon
Effect of insulin on B oxidation
DECREASES B oxidation
Effect of glucagon on glycolysis
Decrease Glycolysis
Net effect of insulin on glycolysis
INC Glycolysis
Effect of Epi/Catecholamine of the FF major metabolic pathway: Glycolysis
INC muscle glycolysis (fight/flight)
DEC liver glycolysis to provide glucose to brain and muscle
Effect of Epi/Catecholamine of the FF major metabolic pathway: Gluco-neo-genesis and glyco-genolysis
INC production of Free glucose
Effect of Epi/Catecholamine of the FF major metabolic pathway: Fat Metabolism
INC Beta oxidation of fats for energy
INC acetyl CoA
Priority goals during starvation
Supply glucose to brain and RBCs
Conserve protein
After 3 days of starvation, brain derives majority of energy from
Ketones
The only components of fats that may be utilized for gluco-neo-genesis
Glycerol from triglycerides
Propionyl CoA from Odd Chain FA metabolism
Energy Yield:
Net amount of ATP produced with anerobic glycolysis of 1 mol of glucose
2 ATP
Energy Yield:
Products produced with 1 Acetyl-Coa in TCA cycle
3 NADH
1 FADH2
2 CO2
1 GTP
Energy Yield:
Net yield of complete oxidation of 1 glucose molecule via malate aspartate shuttle
32 (38)
Energy Yield:
Net yield of complete oxidation of 1 glucose molecule via GLYCERO-PHOSPHATE shuttle
30 (36)
Energy Yield:
Net yield of complete oxidation of 1 molecule of palmitic acid
106 (129)
Energy Yield:
ATP produced by 1 NADH in the ETC
2.5 (3)
Energy Yield:
ATP produced by 1 FADH2 in the ETC
1.5 (2)