Statins and Lipid Lowering Drugs I Flashcards
What is atheroma?
Build up of fatty deposits which form a plaque.
What are the stages of atheroma formation?
Endothelial Dysfunction
Inflammation
Adhesion
Thrombus Formation
What are the risk factors for atheroma formation?
Hypertension
Dyslipidemia
What is dyslipidemia?
This is when an ABNORMAL amount of lipids in the blood is present = Body can’t remove LDL from the blood.
What are the primary disorders of dyslipidaemia?
Familial Hypercholesterolaemia
Polygenic lipid disorders
What are the secondary disorders of dyslipidaemia?
Hypothyroidism Type 2 diabetes Alcohol Abuse Thiazide Diuretics Beta Blockers
What type of fats are triglycerides?
Dietary Fats
What is used for screening of lipids?
Total cholesterol levels
LDL + HDL cholesterol
Triglycerides
What is the strong correlation between LDL cholesterol levels in the blood and the risk of coronary heart disease?
HIGHER levels of cholesterol in the blood results in being at a greater risk of suffering from coronary heart disease.
What are lipoproteins?
A core FULL of fat and cholesterol alongside lipid membranes which contains proteins called APOLIPOPROTEINS.
What are Apolipoproteins?
Act like identification tags for DIFFERENT lipoproteins in the body.
Allow transport of lipoproteins.
Why are apolipoproteins known as ligands?
They bind lipids in order to form lipoproteins.
Where are the exogenous sources of lipids made from?
These arise from dietary fats.
Where are the endogenous sources of lipids made from?
These are made in the liver.
In what form are exogenous sources of lipids absorbed from the intestine?
These are absorbed from the intestine in the form of chylomicrons.
How are endogenous sources of lipids secreted?
Secreted as vLDL.
What is the purpose of lipoprotein lipase?
These remove triglycerides so that it can be taken up into the tissues for storage alongside being used for energy.
What are the 3 sources when metabolised can produce Acetyl - coA?
Glycogen
Triglycerides
Proteins
What can Acetyl - coA be converted into?
Cholesterol.
What percentage of the cholesterol made in the body is made by the liver?
50%
Where is cholesterol synthesised?
Cholesterol is synthesised by the liver and the hepatic tissues.
What is the purpose of HMG - CoA reductase?
This inhibits the synthesis of cholesterol.
Known as a ‘Rate Limiting Step’.
What is the purpose of vLDL?
This is the MAIN transporter of fatty acids.
Where does LDL transport cholesterol?
To the tissues.
What is the purpose of HDL?
When the liver empties -> EXCESS cholesterol is picked up and brought back to the liver.
This removes cholesterol from tissues and bloodstream.
What is the ligand for LDL receptors?
Apo - B100.
What are high levels of App - B100 associated with?
High risk of cardiovascular disease.
What is the name of the subspecies of LDL?
Lipoprotein A
What causes there to be a subspecies of LDL?
It is a genetic variation.
What does Lipoprotein A contain?
APO - A and APO - B.
What are high levels of Lipoprotein A associated with?
Atherosclerosis -> due to these lipoproteins depositing in the blood vessels when in high quantity.
What substance do LDL receptors recognise on LDL?
Apoprotein B100.
What is the link between LDL receptors and cholesterol levels?
The HIGHER the levels of LDL receptors -> the LOWER the levels of cholesterol.
What happens when the LDL binds to the receptor?
Receptor is ENDOCYTOSED.
LDL is removed for usage in the cell.
Receptor is RECYCLED back to the membrane.
Why does the condition familial hypercholesterolaemia occur?
There is either a reduction // defect in the LDL receptors.
What is PCSK9?
It is a proprotein convertase = Activates OTHER proteins.
Where does PCSK9 circulate?
In the bloodstream.
What happens when LDL binds to LDL - PCSK9 receptors?
When the LDL binds -> the receptors are endocytosed as usual but the PCSK9 presence means the LDL receptors are sent to the lysosome where it is DEGRADED.
What is the health condition associated with high levels of PCSK9?
Cardiovascular Disease.
