Metabolism And Nutrition

Front 1

List the glycogen storage diseases

Back 1

Types 1-8:
1) von Gierke disease
2) Pompe disease
3) Cori disease
4) Andersen disease
5) McArdle disease
6) Hers disease
7) Tarui disease
8) Type VIII Glycogen Storage Disease

Front 2

von Gierke disease

Back 2

-AKA Type 1 Glycogen Storage Disease
-Deficiency in the glucose 6-phosphate enzyme of the liver, kidney blocks gluconeogenesis
-Leads to hepatomegaly and hyperuricemia, severe hypoglycemia, lactic acidosis, ketosis

Front 3

Pompe disease

Back 3

AKA Type 2 Glycogen Storage Disease
-Mutation in a-1,4-glucosidase throughout glycogen-producing organs results in a failure to produce glycogen
-Cardiac failure due to insufficient glycogen is fatal in infancy

Front 4

Cori disease

Back 4

AKA Type 3 Glycogen Storage Disease
-Mutation in the debranching enzyme of glycogen-containing tissues reduces the body's ability to break down glycogen to form glucose 1-phosphate
-Symptoms resemble Type 1: hepatomegaly, hyperuricemia, ketosis, lactic acidosis, hypoglycemia

Front 5

Andersen disease

Back 5

AKA Type 4 Glycogen Storage Disease
-Impairment/mutation in branching enzyme of the liver and myocardium results in impaired glycogen synthesis and death from liver cirrhosis (usu. < 2 years)

Front 6

McArdle disease

Back 6

AKA Type 5 Glycogen Storage Disease
-Deficiency in glycogen phosphorylase of skeletal muscle cells results in easy fatigue and cramping/pain upon physical exertion. Otherwise normal lifespan.

Front 7

Hers disease

Back 7

AKA Type 6 Glycogen Storage Disease
-Deficiency in liver phosphorylase results in impaired glycogen breakdown with symptoms that resemble a mild von Gierke syndrome (hepatomegaly, hyperuricemia, lactic acidosis, ketosis, hypoglycemia) -- note that hypoglycemia much milder

Front 8

Tarui disease

Back 8

AKA Type 7 Glycogen Storage Disease
-Deficiency in phosphofructokinase (affecting the muscle and red blood cells) inhibits the progression of glycolysis and results in symptoms like McArdle disease (easy fatigue, muscle cramping/pain upon exertion) with high levels of muscle glycogen

Front 9

Type 8 Glycogen Storage Disease

Back 9

Deficiency in phosphorylase kinase affects phosphorylation-based mediation of glycogen metabolism
-Deficiency => decreased activation of glycogen phosphorylase
-Deficiency => decreased inactivation of glycogen synthase

Front 10

Describe the two forms of arsenic poisoning, including pathway inhibited, mechanism and severity.

Back 10

Arsenate decouples ATP synthesis from glycolysis by mimicking phosphate at glyceraldehyde-3-phosphate conversion to 1,3-bisphosphoglycerate. Arsenite inhibits pyruvate dehydrogenase in its conversion of pyruvate to acetyl CoA, preventing entry into the TCA cycle, which is very severe.

Front 11

Which metabolic disease is expressed primarily in RBCs (results in hemolytic anemia)?

Back 11

Pyruvate kinase deficiency, which inhibits the final step of glycolysis (PEP --> pyruvate) affects only the isozyme related to which cell type?

Front 12

What are the effects of pyruvate carboxylase deficiency?

Back 12

Build-up of lactate (lactic acidosis), pyruvate/alanine, hypoglycemia from inability to perform gluconeogenesis, neurological defects (myelin sheath and neurotransmitter defects)

Front 13

What is the typical treatment for pyruvate dehydrogrenase deficiency and why does it work?

Back 13

High-fat, low-carbohydrate diest bypass pyruvate for the most part, deriving energy from acetyl CoA from FA beta-oxidation.

Front 14

What are the forms of pyruvate dehydrogenase deficiency, and how do they differ from one another?

Back 14

Metabolic is more severe than chronic neurological pyruvate dehydrogenase deficiency (overwhelming, typically-fatal lactic acidosis v. significant psychomotor retardation accompanied by some lactic acidosis). X-liked presents differently in male as opposed to female patients.

Front 15

What is the mechanism of action of cyanide? What are possible treatments?

Back 15

Cyanide binds and blocks Fe3+ in cytochrome oxidase (Complex 4 in the ETC), resulting in back-up of aerobic respiration and lactic acidosis due to anaerobic shift. Treat by competition (oxidizing Hb iron to 3+).

Front 16

Leigh disease is associated with which part of metabolism?

Back 16

The electron transport chain, especially complexes I and IV

Front 17

MCAD deficiency is associated with which part of metabolism?

Back 17

Fatty acid beta oxidation

Front 18

CPT II deficiency is associated with which part of metabolism?

Back 18

Fatty acyl carnitine conversion to fatty acyl CoA (in preparation for beta oxidation)

Front 19

Jamaican vomiting syndrome is associated with which part of metabolism?

Back 19

Fatty acid beta oxidation (inhibition of short- and medium-chain acylCoA dehydration)

Front 20

Proprionic acidemia is associated with which part of metabolism?

Back 20

Odd-numbered-carbon-chain fatty acid catabolism (conversion of proprionic acid to succinyl-CoA). Also amino acid catabolism of M, T, V, I

Front 21

Methylmalonic acidemia is associated with what part of metabolism?

Back 21

Fatty acid catabolism and catabolism of amino acids V, I, T, M --> conversion of methylmalonyl-CoA to succinyl-CoA in a vitamin B12-mediated pathway

Front 22

The Zellweger spectrum is associated with what area of metabolism?

Back 22

Peroxisome formation disorders affect branched and VLCFAs, which must be broken down by alpha oxidation in the peroxisome.

Front 23

Why do diseases affecting VLCFA and branched FAs cause neurodegenerative disorders?

Back 23

Because elevated blood [VLCFA] and [branched FA] disrupts myelin sheaths and neuronal transmission.

Front 24

Refsum disease affects what part of metabolism?

Back 24

Defect in alpha oxidation of branched FA in peroxisomes. Not the same as infantile refsum diseases, which is a Zellweger spectrum disorder.

Front 25

Adrenoleukodystrophy affects what part of metabolism?

Back 25

Defect in VLCFA transporter results in VLCFA accumulation in blood. Not to be confused with neonatal adenoleukodystrophy, which is a Zellweger spectrum disorder.

Front 26

What is the primary effect of alcohol poisoning on metabolism?

Back 26

Increase in NADH/NAD+ ratio

Front 27

What is the key enzyme regulating cholesterol biosynthesis?

Back 27

HMG-CoA reductase

Front 28

What is the pathology in familial hypercholesterolemia?

Back 28

Deficiency in the LDL receptor results in severely diminished ability to clear LDL from blood => very high serum [LDL] and early atherosclerosis

Front 29

Which apoproteins are expressed on chylomicrons?

Back 29

ApoB-48
--On mature, also:
ApoE
ApoCII

Front 30

Which apoproteins are expressed on VLDL?

Back 30

ApoB-100
ApoE
ApoCII

Front 31

Which apoproteins are expressed on LDL?

Back 31

ApoB-100

Front 32

Which apoproteins are expressed on HDL?

Back 32

ApoCII
ApoE

Front 33

What is the function of pyruvate dehydrogenase?

Back 33

Conversion of pyruvate to acetyl CoA

Front 34

What is the active form of pyruvate dehydrogenase?

Back 34

Dephosphorylated

Front 35

What are the general symptoms of organic acidemia?

Back 35

Low white cell count, presence of carnitine esters

Front 36

Which receptor is responsible for insulin-mediated glucose transport?

Back 36

GLUT4