Lipoprotein Pathophysiology

Question 1

ApoA-I
Lipoprotein Association
Primary Source
Functions

Answer 1

HDL
Intestine, Liver
Structural protein for HDL, activator of LCAT binds ABCA1, SR-B1

Question 2

ApoA-II
Lipoprotein Association
Primary Source
Functions

Answer 2

HDL
Liver
Inhibits reverse chol transport

Question 3

ApoA-IV
Lipoprotein Association
Primary Source
Functions

Answer 3

HDL, CM, VLDL
Intestine
Unknown (satiety?)

Question 4

ApoB-48
Lipoprotein Association
Primary Source
Functions

Answer 4

CM
Intestine
Chylomicron synthesis and secretion

Question 5

ApoB-100
Lipoprotein Association
Primary Source
Functions

Answer 5

VLDL, IDL, LDL, LP(a)
Liver
VLDL synthesis and secretion; ligand for binding to LDL-receptor

Question 6

ApoC-I
Lipoprotein Association
Primary Source
Functions

Answer 6

CM, VLDL, HDL
Liver
Inhibits CETP & particle removal

Question 7

ApoC-II
Lipoprotein Association
Primary Source
Functions

Answer 7

CM, VLDL, HDL
Liver
Cofactor for LPL

Question 8

ApoC-III
Lipoprotein Association
Primary Source
Functions

Answer 8

CM, VLDL, HDL
Liver
Inhibits LPL & particle removal

Question 9

ApoE
Lipoprotein Association
Primary Source
Functions

Answer 9

CM, IDL, HDL
Liver & Macrophages
Ligand for binding to LDL receptor and LRP

Question 10

Familial Chylomicronemia Syndrome
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 10

LPL deficiency, apoC-II deficiency
Chylomicrons
Eruptive xanthomas, hepatosplenomegaly,
pancreatitis

Question 11

Familial Dysbetalipoproteinemia
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 11

Abnormal apoE  (i.e., apoE- 2/2) Chylomicrons, VLDL remnants  beta-VLDL
Palmar and tubero-eruptive xanthomas, premature atherosclerosis

Question 12

Familial Combined Hyperlipidemia
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 12

Unknown
VLDL, IDL, LDL
premature atherosclerosis

Question 13

Familial Hypertriglyceridemia
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 13

Unknown
VLDL, occasionally chylomicrons
Usually none

Question 14

Familial Hepatic Lipase Deficiency
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 14

Hepatic lipase Deficiency
VLDL remnants
premature atherosclerosis

Question 15

Familial Hypercholesterolemia
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 15

LDL-receptor deficiency
LDL
Tendon xanthomas
premature atherosclerosis

Question 16

Familial defective ApoB-100
Molecular Defect
Lipoproteins Elevated
Clinical Findings

Answer 16

Abnormal apoB-100 (i.e., Arg3500 Gln)
LDL
Tendon xanthomas
premature atherosclerosis

Question 17

Familial apoA-l deficiency
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 17

apoA-l deficiency
HDL < 5mg/dl TG normal
Planar xanthomas, Corneal opacities
premature atherosclerosis

Question 18

Familial apoA-l structural mutants
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 18

Abnormal apoA-l
HDL 15–30 TG increased
Often none; sometimes corneal opacities

Question 19

Familial LCAT deficiency
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 19

LCAT deficiency (complete)
HDL <10 mg/dl TG increased
Corneal opacities, anemia, proteinuria, renal insufficiency

Question 20

Fish-eye disease
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 20

LCAT deficiency (partial)
HDL < 10mg/dl TG increased
Corneal opacities

Question 21

Tangier disease
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 21

ABCA1 deficiency
HDL < 5mg/dl; TG usually increased
Corneal opacities, enlarged, orange tonsils, hepatosplenomegaly, peripheral neuropathy
premature atherosclerosis

Question 22

Familial hypoalpha-lipoproteinemia
Molecular Defect
Lipoprotein Abnormalities
Clinical Findings

Answer 22

Unknown
HDL 15–35 TG normal
Often none, sometimes corneal opacities
premature atherosclerosis possible