Lipid Lowering Agents Flashcards
What are Lipid Carriers (Lipoproteins)?
Triacylglycerols and cholesterol can’t flow freely in blood at high levels
- require “carriers”
What are the 4 types of Lipid Carriers (Lipoproteins)?
- Chylomicron
- Very Low Density Lipoprotein (VLDL)
- Low Density Lipoprotein (LDL)
- High Density Lipoproteins (HDL)
What are Chylomicrons?
- Carrier of dietary lipids from intestine
to liver - TG-rich, some Chol
What are Very Low Density Lipoprotein (VLDL)?
- Carrier of lipids from liver to periphery * TG-rich, some Chol
What are Low Density Lipoprotein (LDL)?
“BAD chol”
* Carrier of lipids from liver to periphery * Chol-rich,someTG
What are High density Lipoproteins (HDL)?
“GOOD chol”
* Scavenge cholesterol from artery wall
Dietary and liver-synthesized lipids are absorbed @ _______
small intestine
_______ carry absorbed fat to adipose tissue (and ~muscle)
Chylomicrons
Lipoprotein lipases on endothelial cell surfaces liberates ________ + ______
free fatty acid + glycerol
Chylomicron remnant taken up by the ________ for processing
liver
Cholesterol is synthesized in the _____
liver
Describe the process of Cholesterol
- Cholesterol is synthesized in the liver
- Liver packages TG and cholesterol into VLDL
- VLDL carries these lipids to tissues, especially adipose
- Lipoprotein lipases on endothelial cell surfaces liberates free fatty acid + glycerol
- VLDL->IDL->LDL as FA are removed
- LDL carries cholesterol to other peripheral tissues; excess is taken up again by liver
- HDL carries excess cholesterol scavenged from vessels and tissues back to the liver
What are 2 Lipid Disorders?
- Pancreatitis
- Atherosclerosis
What is Pancreatitis?
Pancreatitis: Inflammation of the pancreas
* Caused by elevated plasma Triglycerides
* Primarily elevated chylomicrons, VLDL as well.
What is Atherosclerosis?
Atherosclerosis - Deposition of cholesterol in arteries
* Problem in coronary and cerebral blood flow
* Caused by elevated plasma CHOLESTEROL & TRIGLYCERIDES
* Primarily derived from low density lipoproteins (LDL’s)
- 50% of Western Society have ↑ LDL levels
- favors “abnormal deposition” to vessel walls
Where do emboli lodge in Atherosclerosis?
- Carotid artery thrombosis
- Coronary artery thrombosis
- Other sites?
What are risk factors for Coronary Heart Disease?
- Age
o Male >45 years of age or female >55 years of age - Family history of premature CHD
o 1st degree relative (male <55 years of age or female <65 years of age when the first CHD clinical event occurs) - Current cigarette smoking
- Hypertension
o Blood pressure ≥140/90 or use of antihypertensive medication
What steps in exogenous or endogenous pathway could you disrupt to ↓ plasma chol?
Cholesterol:
* ↓ GI uptake
- ↓ dietary intake in gut
- ↓ reabsorption of bile acids in gut
- ↓ absorption of cholesterol in gut
- ↓ endogenous cholesterol synthesis in liver
- ↓ LDL levels
- ↓ VLDL production by the liver
- ↑ LDL receptors on hepatocyte surface
What are the drugs for Hypercholesterolemia?
- Non-pharmacological approach – Dietary fiber
- Cholesterol synthesis inhibition - Statins
- Cholesterol Absorption Inhibitor – Ezetimibe
- Bile Acid Binding Resins –
Cholestyramine, Colestipol - Inhibiting LDL receptor degradation - Evolocumab
Non-pharmacological approach for Hypercholesterolemia?
Dietary fiber
Cholesterol synthesis inhibition drugs for Hypercholesterolemia?
Statins
Cholesterol Absorption Inhibitor drugs for Hypercholesterolemia?
Ezetimibe
Bile Acid Binding Resins drugs for Hypercholesterolemia?
Cholestyramine, Colestipol
Inhibiting LDL receptor degradation drugs for Hypercholesterolemia?
Evolocumab
What is Dietary Fiber?
is dietary material that is resistant to the action of digestive enzymes (soluble and insoluble)
What is insoluble fiber?
is indigestible
* Sources: vegetables, whole grains
What is soluble fiber?
can be broken down by gut microbiome * Sources: oatmeal, oat bran, fruit
What does the non-pharmacological approach for dietary fiber do?
Soluble fiber binds chol in gut to reduce plasma chol
What does 100g/day oat bran diet (cereal and muffins) for 3 weeks do?
- Total Cholesterol 19%
- LDL Cholesterol 23%
What are the Choleterol Synthesis Inhibition drugs?
- Rosuvastatin, atorvastatin, simvastatin, lovastatin etc
- Drug of 1st choice for most patients with risk for coronary heart
disease (atherosclerosis) - ↓ LDL levels (modest HDL increase).
- Also ↓ triglyceride levels.
- In patients with coronary artery disease – decreased cardiac morbidity, mortality, reduced incidence of stroke
- Benefits seen with initial high or normal cholesterol