Biochem 23

Front 1

Major fuel and energy supply during fasting and increased energy demand

Back 1

Fatty acids

Front 2

Energy source for the brain during fasting

Back 2

ketone bodies

Front 3

What type of fatty acid is stored and released form adipose tissue

Back 3

Long chain fatty acids

Front 4

How are fatty acids carried in the blood

Back 4

bound to albumin

Front 5

Acyl CoA synthetase

Back 5

converts fatty acids to fatty acyl CoA

Front 6

What binds to acyl CoA to transport fatty acids into the mitochondriA

Back 6

Carnitine

Front 7

Fate of Acetyl CoA from beta oxidation

Back 7

TCA cycle or ketone body or cholesterol

Front 8

Where does medium chain fatty acid oxidation occure

Back 8

only in the liver and does not need carnitine because it is more soluble then long chains

Front 9

Fate of the terminal 3 carbons of odd chain fatty acids

Back 9

The propionyl CoA is transformed into succylny CoA and enters the TCA cycle.

Front 10

Site of initiation of very long chain fatty acid metabolism

Back 10

peroxisome

Front 11

Site of ketone body synthesis

Back 11

The liver produces ketones but can not use them as an energy source

Front 12

Liver enzymes AST and ALT

Back 12

Aspartate amino transferase and alanine amino transferase, both are released when there is damage to the liver cell plasma membrane

Front 13

Effect of epi and noreepi on adipose cells

Back 13

increase lipolysis

Front 14

Principle fatty acid oxidized for fuel

Back 14

long chain fatty acids

Front 15

Three main long chain fatty acids

Back 15

Palmitate, oleate, and stearate

Front 16

Triacylglycerol

Back 16

3 fatty acids bound to a glycerol backbone

Front 17

Fatty acids of animals and veggies

Back 17

animals contain saturated and monounsaturated long chains. Veggies contain linoleate and long chain poly unsaturated fatty acids, also have a small amount of branched fatty acids and odd chain fatty acids

Front 18

Product of fatty acid synthesis

Back 18

palmitate. Made by the liver and packaged in VLDL

Front 19

How do fatty acids enter a cell

Back 19

through a membrane transported and by diffusion

Front 20

Fatty acids are activated to

Back 20

fatty acyl CoA, by the enzye acyl CoA synthetase. Also called thiokinase, ATP is needed for the reaction

Front 21

Three location of acyl CoA synthetase

Back 21

ER, outer mitochondrial membrane, and peroxisome

Front 22

Location of medium chain fatty acid Acyl CoA synthetase

Back 22

Outer mitochondrial membrane of the liver and kidney

Front 23

Three fates of fatty acyl CoA

Back 23

Energy; beta oxidation and ketogenesis. Storage as triacylglycerides. Membrane lipids; phospholipids and sphingolipids.

Front 24

Classic presentation of CPT II deficiency. Most common deficiency of fatty acid metabolism.

Back 24

Patient is weak, hypoglycemic and hypoketosis. Metabolic decomp is not severe. CPK levels and long chain acylcanitines are elevated in the blood.

Front 25

SAM

Back 25

S-adenosylmethionine

Front 26

Carnitine:palmitoyltransferase AKA canitine acyl tranferase

Back 26

I is located on the outer mitochodrial membrane and adds carnitine to acyl CoA in exchange for CoA. The Acyl carnitine is transported across the membrane by translocase. II is in the inner mitochondrial membrane and transfers the CoA back to fatty acyl in exchange for carnitine. Both I and II need ATP

Front 27

What tissue takes up the largest amount of carnitine

Back 27

skeletal muscle

Front 28

Vitamin precurser for FAD

Back 28

Riboflavin

Front 29

CoQ

Back 29

recipient in the electron transport chain

Front 30

Precursor of CoA

Back 30

Pantothenate

Front 31

How does beta oxidation conserve energy

Back 31

FAD(2H), NADH go to electron transport chain and FADH gives 2 ATP and NADH gives 3 ATP. The acetyl CoA goes into the TCA cycle or converted to ketones

Front 32

Steps of beta oxidation with enzymes

Back 32

1. Acyl CoA dehydrogenase adds a double bond between C2 and C3, FADH is made. 2. Enoyl CoA hydratase adds water to the double bound putting the OH group on the beta carbon. 3. Beta hydroxy acyl CoA dehydrogenase oxidizes the OH group to a double bonds O, gives NADH. Beta keto thiolase along with CoA cleaves off acetyl CoA and a fatty acyl CoA.

Front 33

MCAD, medium chain acyl CoA dehydrogenase deficiency.

Back 33

oxidation of fatty acids is blocked at the 6-10 carbon stage. The medium chain fatty acids will accumulate in the blood and urine as decanoic and octanoic acid. If it was LCAD deficiency long fatty acids would appear in the blood but not urine since they are not water soulable

Front 34

Adding double bonds to fatty acids

Back 34

Human body can only add a double bond up until carbon 9. If a fatty acid has a double bond after the ninth carbon then it is essential.

Front 35

Unsaturated fatty acid metabolism

Back 35

The cis bond must be made trans and moved to between carbon 2 and 3. the beta oxidation can continue. If there is conjugated double bounds at C2 and C4 then a reductase, NADPH dependent, can form one double bond at C3

Front 36

Linoleate

Back 36

essential fatty acids with a double bond at C12, is required for arachidonate production.

Front 37

Odd chain fatty acid metabolism

Back 37

Beta oxidation continues at normal until 5 carbons are left. The remaining 5 carbons are split to acetyl CoA and propyl CoA. Propionyl CoA is converted to methylmalonyl CoA by propionyl CoA carboxilase (ATP, Biotin, CO2). Methylmalonyl CoA is then converted to succinyl CoA by methylmalonyl CoA Mutase (B12). This can then enter the TCA cycle. Its the only fatty acid carbons that can be made into glucose. in the TCA cycle by making oxaloacitate.

Front 38

Storage of fatty acids

Back 38

long chain are stored in adipocytes but medium chain are more water soluble and not stored this way. They enter the mitochondrial matrix after a meal.

Front 39

Actions of ADP dependent protein kinase B in fatty acid oxidation.

Back 39

Glucagon has the came actions. Causes phosphorylation of Acetyl CoA carboxylase with lowers the amount of Malatyl CoA with inhibits CAT I. Insulin has the reverse action of acetyl CoA carboxylase (ABC) activating it. After a high glucose meal you want to store energy not break it down.

Front 40

Regulation of beta oxidation

Back 40

the cells energy level. Amount of ATP and NADH available.

Front 41

AMP levels during exercise

Back 41

they increase activating AMP dependent kinase with increases beta oxidation but also recruits more GLUT transporters to the muscle surface.

Front 42

Beta oxidation depends on

Back 42

oxygen, strictly aerobic pathway. Good blood supply. Can not happen in cells that lack mitochondria ( RBC).

Front 43

Omega oxidation

Back 43

adds a carboxylic acid to the omega end a a fatty acid creating a dicarboxilic acid. Will accumulate is there is an enzyme deficiency in beta oxidation. Happens in the ER.

Front 44

Oxidation of xenobiotics

Back 44

by omega oxidation in the peroxisome.

Front 45

Very long chain fatty acids, over 20 carbons

Back 45

oxidation begins in the peroxisome. When the chain length becomes shorter it is transferred to the mitochondria for beta oxidation Short and medium chains can be attached to carnitine in the peroxisome before transport.

Front 46

Zellweger's syndrome

Back 46

defective peroxysomal biogenesis

Front 47

Refsum's disease

Back 47

defect in a peroxisome enzyme that leads to retinitis pigmentosa, cerebellar ataxia, and chronic polyneuropathy

Front 48

Biproduct of peroxide oxidation of fatty acid

Back 48

hydrogen peroxide.

Front 49

Fatty acids from chlorophyll

Back 49

branched chain fatty acids. Phytanic and pristanic acid.

Front 50

Ketone body synthesis

Back 50

occurs in the mitochondrial matrix from acetyl CoA generated from fatty acid oxidation. Only when fatty acid levels are high because this is not the favored direction of the reaction, ketone body breakdown is favored.

Front 51

Ketone metabolism

Back 51

beta hydroxybuterate is transformed into acetoacetate by hydroxybuterate dehydrogenase. This is then metabolised to 2 acetyl CoA that enter the TCA cycle.

Front 52

1 ketone body produces 21.5 ATP

Back 52

random fun fact

Front 53

When are fatty acids used for energy

Back 53

when ever there level become high in the blood. Fasting, and exercise, and low carb diet. Decrease in insulin, increase in glucogon, epi, norepi.

Front 54

Why are children more prone to ketacidosis

Back 54

they metabolize glycogen faster and there fore enter the fasting state sooner. usually 1 day compared to 3 days for adult to get ketoacidosis.

Front 55

ATP homeostasis

Back 55

controlled by all factors that deal with metabolism; insulin, glucogon, epi, amp kinase.

Front 56

fatty acid oxidation of gluconeogenasis

Back 56

if fatty acid levels are high enough ATP is present to stop glucose production. The drug meformin turn on AMP kinase which increases beta oxidation and decreases glucose need and level.

Front 57

Insulin effect on glucose-6-P hexokinase

Back 57

a decrease in insulin inhibits Glucose-6-P hexokinase thereby decreasing the rate of glucose entry into glycolysis and uptake from the blood. In this case fatty acid oxidation would be favored.

Front 58

What used fatty acid as major fuel source

Back 58

skeletal muscles, heart, and the liver.

Front 59

When is acetyl CoA shifted to ketone production

Back 59

when the level of NADH and FADH are high enough to supply the needed ATP of the liver. At this time oxaloacetate is diverted to malate for gluconeogenysis

Front 60

Lactate use

Back 60

some can be used by the heart and the rest is converted to glucose.

Front 61

Manifestation of MCAD deficiency

Back 61

Hypoglycemia and hypoketosis. Fatty acids are metabolized until they reach medium chain length. Treat these patients with a high carb diet and avoid fasting.

Front 63

correlation of hyperosmolar sate and nervous system dysfunction

Back 63

high correlation.