Lipids/obesity

Question 1

critical enzyme mediating the transfer of triglyceride to Apo B48

Answer 1

MTP (microsomal triglyceride transfer protein)

Question 2

defect in MTP leads to what clinical problem

Answer 2

abetalipoproteinemia

Question 3

defect in Apo B48 leads to what clinical problem

Answer 3

hypobetalipoproteinemia

Question 4

lipoprotein of chylomicrons

Answer 4

Apo B48

Question 5

lipoprotein of HDL

Answer 5

Apo A

Question 6

where are chylomicrons formed

Answer 6

brush border intestinal cells

Question 7

which enzyme clears chylomicrons from the blood

Answer 7

lipoprotein lipase

Question 8

where is LPL located

Answer 8

capillary walls

Question 9

lipoprotein activators of LPL

Answer 9

Apo CII

Apo A

Question 10

lipoprotein inhibitors of LPL

Answer 10

Apo CIII

ANGPTL3/4

Question 11

chylomicron remnants are cleared by binding to which receptors in the liver

Answer 11

LDL receptor

Question 12

ligand for chylomicron remnant binding

Answer 12

Apo E

Question 13

Familial chylomicronemia syndrome defect

Answer 13

LPL mutation

Question 14

clinical features of Familial chylomicronemia syndrome

Answer 14

lipemia retinalis

eruptive xanthomas

Question 15

treatment of Familial chylomicronemia syndrome

Answer 15

dietary fat restriction

Question 16

Lipoprotein deficiency syndromes with hypertriglyceridemia (similar to FCS)

Answer 16

Apo CII deficiency
Apo A
(both are activators of LPL)

Question 17

dysbetalipoproteinemia defect

Answer 17

Chylomicron remnant problem
Apo E (E2/E2 genotype)

Question 18

lipid panel phenotype of dysbetalipoproteinemia

Answer 18

elevations in both serum TG and cholesterol (300-500)

Question 19

which lipid disorder causes palmar xanthomas

Answer 19

dysbetalipoproteinemia

Question 20

treatment of dysbetalipoproteinemia

Answer 20

statin, fibrate niacin, secondary causes

Question 21

lipid panel disorder in Familial Lipodystrophy

Answer 21

elevated TG

Question 22

which apolipoprotein is used in endogenous VLDL production

Answer 22

Apo B100

Question 23

which enzyme converts VLDL to LDL in the liver

Answer 23

Hepatic lipase

Question 24

what is the ligand for LDL -LDL receptor

Answer 24

Apo B100

Question 25

which protein binds to LDL receptor and prevents it from recycling

Answer 25

PCSK9

Question 26

defect in FH

Answer 26

LDL receptor

Question 27

defect in Familial defective apolipoprotein B

Answer 27

Apo B (cannot bind to LDL receptor)

Question 28

defect in sitosterolemia

Answer 28

ABCG5 receptor

absorbs plant cytosterols inappropriately

Question 29

how to diagnose sitosterolemia

Answer 29

check sitosterol levels

Question 30

where does HDL pick up excess peripheral cholesterol

Answer 30

peripheral macrophages (foam cells)

Question 31

what does LCAT enzyme do

Answer 31

makes mature HDL from nascent HDL molecules

Question 32

hepatic receptor for HDL

Answer 32

SR-B1 (not may of these receptors, so HDL transfers cholesterol to VLDL/LDL particles)

Question 33

which enzyme allows HDL to transfer cholesterol to VLDL/LDL particles

Answer 33

CETP

Question 34

deficiency that causes very low HDL

Answer 34

Apolipoprotein A1 deficiency

Question 35

defect in Tangier disease

Answer 35

ABCA1 on peripheral macrophages

HDL can’t pick up cholesterol from “foam cell”

Question 36

LCAT deficiency

Answer 36

can’t form mature HDL

fish eye disease

Question 37

CETP deficiency

Answer 37

mostly Japanese

high HDL > 100

Question 38

CETP role in insulin resistance

Answer 38

1) transfers TG from VLDL to HDL particles
HDL particles then take up
leads to LOW HDL levels
2) transfers TG from VLDL to LDL and cholesterol from LDL to VLDL
results in small, dense LDL

Question 39

treatment of pt with DM and partial familial lipodystrophy

Answer 39

metformin

pioglitizone

Question 40

monogenic causes of obesity

Answer 40

melanocortin 4 receptor (MC4R)
fat mass and obesity-associated gene (FTO)
proopiomelanocortin gene (POMC)
leptin deficiency (LEP)
Prader-willi

Question 41

monogenic obesity that starts early in life (3)

Answer 41

MC4R
POMC deficiency
Leptin deficiency

Question 42

obese child with red hair, adrenal insufficiency

Answer 42

POMC deficiency

Question 43

avg age of weight gain in FTO mutation

Answer 43

7

Question 44

underweight infant with hypotonia, wt gain starting around age 5

Answer 44

Prader-Willi

Question 45

role of Coenzyme Q10 in preventing statin-induced myalgias

Answer 45

doesn’t work (recent meta-analyses)