Lipoprotein Flashcards
1
Q
Tangier
A
- TD caused by mutation in ABC1 transporter gene
- transporter involved removal of membrane cholesterol by HDL particles
- Nascent apo A-1 do not acquire cholesterol
- Do not produce mature HDL, i.e. LOW plasma HDL
- Cholesterol accumulates in extrahepatic tissues, particularly the reticuloendothelial system
- Engorged macrophages accumulate in lymphoid tissues, eg. tonsils
- Plasa LDL levels 1/3 nl b/c transfer of CE from HDL to VLDL is not possible
2
Q
Type I Hyperlipidemia/Hyperchylomicronemia
A
- Familial LPLase def.
- OR apoC-II deficiency
- production of abnormal LPLase
- increased TAG
- primary hyperlipidemia
- hyperchylomicronemia
- rare
- Type Ia: LPLase def.
- Type Ib: Apo-CII def
- Type 1c: LPL inhibitor protein def.
3
Q
Type IIa Hyperlipidemia/hypercholesteremia
A
- LDL receptor defect
- high LDL levels
- nl VLDL levels
- 4 possible mutations in LDL receptor gene:
- Class 1 mutation: complete loss of receptor synthesis
- Class 2 mutation: LDL receptor synthesized but is not processed
- Class 3 mutation: Receptor unable to bind LDL
- Class 4 mutation: receptor binds LDL but cannot internalise
- increased Cholesterol (LDL)
4
Q
Type IIb Hyperlipidemia
A
- elevated LDL cholesterol
- hypertriglyceridaemia (primarily VLDL) & corresponding decrease in HDL
- most common inherited lipid disorder
5
Q
Type III Hyperlipidemia
A
- ApoE abnormalities interfering with hepatic chylomicron & IDL
- Serum TAG elevated
- increased TAG
- high remnants chylomicron
- high IDL
- high VLDL & beta-VLDL
6
Q
Type IV Hyperlipidemia/Hyperprebetalipoproteinemia
A
- Overproduction of VLDL & decreased elimination
- increased TAG
- high chylomicron
7
Q
Type V Hyperlipidemia
A
- increased VLDL
- decreased LPLase
- increased TAG
- secondary hyperlipidemia
- partial LPL activity and/or partial apo-CII
- elevated VLDL & chylomicrons
- caused by obesity, diabetes, alcholism & oral contraceptives
8
Q
LCAT def.
A
- breakdown in reverse cholesterol transport
