Drug therapy in the treatment of hyper lipoproteinemias Flashcards
(41 cards)
what are two roles of apolipoproteins
- ligands for cellular receptors… act as almost a zip code mechanism
- cofactors for various enzymes involved in lipoprotein metabolism
Name some physiologic functions of lipoproteins
- help to transport lipids, triglycerides, and cholesterol in the circulatory system
- supply energy to muscle
- provide cholesterol for synthesis of steroid hormones, bile acids, and cell membrane synthesis
Biggest lipoprotiens have the ____density
- lowest
Name the important lipoproteins from least to most dense
- Chylomicrons
- VLDL
- LDL
- Lp(a)
- HDL
what lipoprotein is the most involved in disease?
- LDL
Hyperlipoproteinemas are associated with what condition?
- atherosclerosis
atherosclerosis is related to what two conditions?
- coronary heart disease
- stroke
LDL does not contain a lot of ____ but contains a lot of ______
- Triglycerides; cholesterol
give the pathophys of hyperlipidemia with LDL
- LDL oxidized in subendothelial space to give inflammatory response via activation of foam cells
How does HDL lower cholesterol?
- binds cholesterol and promotes reverse cholesterol transport from tissues to liver
What three beneficial properties does HDL have?
- anti-inflammatory
- anti-oxidant
- anti-thrombotic
What enzyme is responsible for breaking down lipoproteins?
- Lipoprotein lipase, into free fatty acids and either remnants in the exogenous, or IDL in the endogenous
what are two fates of LDL in normal metabolism?
what would be a pathological fate
- uptake into liver
- uptake into extra hepatic tissue
accumulation of LDL in the subendothelial space
what is LDL-receptor gene regulated by?
- amount of cholesterol and other sterols in the body
Describe role of SCAP?
- sterol sensing domain; cholesterol inhibits SCAP-SREBP complex to golgi for processing to active transcription factor; if sterol is present, no processing to become an active transcription factor
Name 4 challenged in pharmacotherapy of hyperlipediemias?
- inadequate changes in lipid profiles ( so just the efficacy of the drug)
- patient tolerance of drug (toxicity)
- variations in genotype
- multiple dyslipeidemias
What is the most common inhibitor of cholesterol synthesis
- Statins ( reversible competible inhibitor of HMG CoA reductase )
What is the result biochemically of statins
- no mevalonate from HMG CoA… lower cholesterol synthesis so you decrease VLDL levels
what is the result of stains on LDL receptors?
- Statins inhibit cholesterol synthesis; decrease C levels in the liver and you get more LDL receptors TO INCREASE LDL RECEPTORS!
what specific statin is the best at LDL lowerin?
- Crestor (rosuvastatin)
what is the result of statins in HDL?
- increases it
what are the side effects of statins
- muscle complaints (from myalgia to rhabdomyolysis)
- memory loss
- Type II diabetes
What other factors besides HMG-CoA reductase inhibition might affect ability of individual statins to lower LDL (3 of them)
- dose limiting adverse reactions
- differentaial hepatic uptake via SLCO1B1
- metabolism/bioavailability
What is hte main inhibitor of LDL-R degradatin?
PCSK9 inhibitor