Hyperlipidemia Flashcards
What’s hyperlipidemia
Abnormally high levels of a lipid or lipids in the blood
Lipids/lipoproteins affected, plasma look, cause of each of the following hyperlipidemias
Type-I familial hyperchylomicronemia
Type-II Familial Hypercholesterolemia
Type-III Familial
dysbetalipoproteinemia
Type-IV Familial Hypertriglyceridemia
How do you diagnose hyperlipidemia
Lipoprotein electrophoresis, lipoproteins have a net negative charge
Movement of DNA on electrophoresis
shorter bands move further
Moves from cathode (-) to anode (+)
Why wouldn’t there be CMs in a lipoprotein profile
Fasting
Hyperlipidemia lipoprotein profiles
Type 1 familial hyperchylomicronemia (causes, symptoms)
Genetic disorder of lipoprotein metabolism
Increased chylomicrons caused by apoCII or lipoprotein lipase deficiencies
symptoms (develop before 10): jaundice, skin xanthomas
Type 3 familial dysbetalipoproteinemia
Clearance of CM/VLDL remnants from the circulation is defective
apoE on the remnant surface is defective
What is apolipoprotein E (apoE)
Ligand on the remnant surface for the remnant receptor
CM/VLDL remnant travels to the liver where the remnant receptor recognizes apoE which triggers receptor-mediated endocytosis and the remnant is broken down and recycled
3 types of apoE? Which one is normal? What are the two important positions
E2, E3, E4
E3 is normal
112 Cysteine
158 Arginine
ApoE2 in Type 3 familial dysbetalipoproteinemia
ApoE2 has reduced affinity for the remnant receptor and can lead to Type 3 Familial dysbetalipoproteinemia
Remnant receptor is functional but Arg158 is changed to Cys which alters the structure
Remnants accumulate in circulation
Treatment: no cure but try to reduce cholesterol
T/F everyone with a mutant ApoE2 develops type 3 familial dysbetalipoproteinemia
false
