Hyperlipidemia Flashcards
VLDL
liver
delivers hepatic TGs to peripheral tissue
LDL
formed from IDL
delivers hepatic cholesterol to peripheral tissues
chylomicrons
intestine
delivers dietary TGs to peripheral tissue and cholesterol to the liver
Lp(a)
LDL + protein (a) that resembles plasminogen
found in atherosclerosis and CAD (inhibits thrombolysis)
desired LDL level
160
desired HDL level
men: > 40
women: >50
high: >60
desired TG level
200
LDL receptor
in liver and peripheral tissues
bind ApoB
apolipoproteins
hydrophobic core with cholesteryl esters and TGs surrounded by unesterfied cholesterol, phospholipids and apoproteins
CETP
found on vascular surface
transfers cholesterol esters to other lipoprotein particles
LPL
degrades TGs circulating in chylomicrons and VLDLs
ApoC-II
cofactor for LPL
ApoC-III
inhibits lipoportein binding to receptors
PPAR-a
nuclear transcription factor
upregulates LPL and HDL
ApoB-48
intestine
found in chylomicrons
ApoB-100
liver
found in VLDL, IDL, LDL
ligand for LDL receptors
primary chylomicronemia
apoC-II or LPL defect
elevated chylomicrons, VLDL
pancreatitis
familial hypertriglyceridemia
LPL defect (defective VLDL metabolism)
elevated VLDL, TG
pancreatitis
familial dysbetalipoproteinemia
defective metabolism of VLDL, chylomicrons, ApoE defect
elevated IDL, VLDL, cholesterol, TG
atherosclerosis
familal combined hyperlipidemia
increased ApoB
elevated VLDL, LDL
premature atherosclerosis
familial hypercholesterolemia
LDL receptor, ApoB defet
elevated LDL
premature atherosclerosis
desirable total cholesterol
240
secondary hyperlipidemia causes: hypertriglyceridemia
DM, alcohol, severe nephrosis, estrogen, uremia, corticosteroids, myxedema, hypopituitarism, acromegaly, immunoglobulin-lipoprotein complex disorders, lipodystrophy, protease inhibitors
secondary hyperlipidemia causes: hypercholesterolemia
hypothyroidism, early nephrosis, resolving lipemia, immunoglobulin-lipoprotein complex disorders, anorexia, cholestasis, hypopituitarism, corticosteroids
dietary management of hyperlipidemia
limit calories from fat and cholesterol
eat complex carbs and fiber
weight reduction, calorie restriction and alcohol restriction
dietary factors that influence hyperlipidemia
increased TGs: excess calories, alcohol, total fat
increased LDL: cholesterol, saturated, and trans fat
increased VLDL: sucrose and fructose
statins
competitive and reversible HMG-CoA reductase inhibitors and upregulate LDL receptors (promote ER to Golgi transport and cleavage of SREBP)
strongest effect on LDL
UGT1A1 responsible for biotransformation of all statins
reduce CHD risk
AE: rhabdomyolysis (creatinine and kidney failure), teratogen, hepatic, GI distress, sleep disturbance/memory loss
bile acid resins
bind bile acids and prevent reabsorption
AE: GI, bad taste, hypertriglyceridemia, prevents absorption of other drugs and fat soluble vitamins
ezetimibe
prevents absorption of dietary cholesterol
niacin
inhibits release of FFA from adipocytes, decrease TG syn., decrease VLDL, increase transfer of cholesterol from macrophage to HDL, and enhances LPL to convert VLDL to LDL
decrease LDL and TG
reduces Lp (a) and increases HDL
reduces VLDL synthesis
AE: flushing (less for ER), hepatic, GI, hyperucemia, insulin resistance, myositis, eyes (conjunctivitis, cystoid macular edema, retinal detachment), and skin (dry, pruritus, ichthyosis, acanthuses nigricans)
lovastatin
metabolized by CYP3A4
intermediate potency and efficacy
simvastatin
metabolized by CYP3A4 intermediate potency and efficacy
pravastatin
metabolized by sulfating, oxidation and glucoronidation
low potency, low efficacy
atorvastatin
metabolized by CYP3A4 (and beta oxidation and glucoronidation)
long T1/2
high potency, high efficacy
rosuvastatin
metabolized by CYP2C9 (and glucoronidation)
long T1/2
high potency, high efficacy
fluvastatin
metabolized by CYP2C9
fibrates
bind PPARalpha nuclear receptor: upregulates LPL and HDL
AE: gallstones, myopathy, increased liver enzymes, reflux, diarrhea, possible teratogen
gemfibrozil
metabolized by glucoronidation (UGT1A1)
reduces statin metabolism UGT1A1 responsible for biotransformation of all statins
fenofibrate
active metabolite: fenofibiric acid
CI: renal disease
N-3 fatty acids
decrease TG, BP, platelet
anti-arrhythmic
reduce CHD
sources: fatty fish, fish oils, walnuts, flaxseed, rapeseed, soybean, canola oil