Module 12 Flashcards
Coronary heart disease occurs when coronary blood circulation fails to adequately supply the ______ with blood.
heart
Coronary heart disease is primarily caused by _________.
atherosclerosis
__________ occurs when plaque builds up on the walls of the arteries. This causes the _______ to narrow and results in decreased blood flow to the ______.
Atherosclerosis
artery
heart
The risk of developing CHD (coronary heart disease) is _________ related to the levels of __________ in the blood.
directly
cholesterol
Those with high blood __________ are at high risk of developing CHD.
cholesterol
In Canada, CV disease causes _____ of all deaths. This is _____ than any other illness.
1/3rd
more
Cholesterol is an important molecule that supports many physiological roles. Where is it found (primarily) and what is it a precursor of?
Found in cell membranes
Precursor of steroid hormones and bile salts
Where do humans obtain cholesterol from?
Exogenous (dietary) sources and through synthesis (endogenous) which primarily occurs in the liver
Approximately __% of the cholesterol in humans is acquired where? Where is the rest acquired from?
80% of cholesterol is synthesized by the liver, the remaining 20% is acquired from dietary sources
Where do most drugs targeting cholesterol act?
Since the liver produces 80% of cholesterol in the body, most drugs target the liver to decrease cholesterol synthesis
The basic structure of lipoproteins includes an outer ________ ____ made up of _________. This allows lipoproteins to be _______ in ________.
hydrophilic shell
phospholipids
soluble
plasma
What is the core of lipoproteins composed of?
The core is lipophilic, composed of triglycerides and cholesterol.
What is the primary function of lipoproteins
Transport cholesterol and triglycerides in the blood.
Why are lipoproteins required for transport of cholesterol and triglycerides?
Triglycerides and cholesterol are lipophilic and thus require a transporter (i.e. lipoproteins) to be soluble in the blood
All lipoproteins have __________ embedded in the phospholipid shell.
apolipoproteins
Apolipoproteins have three functions, what are they?
1 - Allow recognition by cells which may bind and ingest lipoproteins
2 - Activate enzymes that metabolize lipoproteins
3 - Increase the structural stability of lipoproteins
Lipoproteins that contain __________ __ transport cholesterol from non-hepatic tissue back to the liver whereas lipoproteins that contain _________ ____ transport cholesterol to non-hepatic tissue
Lipoproteins w/ apolipoprotein A-1 –> transport cholesterol from non-hepatic tissue, back to the liver
Lipoproteins w/ apolipoprotein B-100 –> transport cholesterol to non-hepatic tissue
Lipoproteins are named based on what quality?
What are the different names following this classification?
Their density
VLDL - very low density lipoprotein
LDL - low density lipoprotein
HDL - high density lipoprotein
Describe how the density of lipoproteins indicates the protein:lipid ratio.
Low density means there is relatively more lipid than protein in the lipoprotein.
High density indicates that there is more protein than lipid.
What is the function of VLDL?
Deliver triglycerides from the liver to adipose tissue and muscle.
VLDL:
They have a ________ rich core and account for almost all of the ________ content in the blood.
triglyceride
triglyceride
Almost all of the triglyceride content in the blood comes from what source?
VLDL
Describe the link between VLDL and atherosclerosis.
The link is controversial, as some studies indicate a link, and others do not. There is a suggestion that high VLDL levels contributes to atherosclerosis.
What apolipoprotein does VLDL contain? Where is the “cargo” deposited?
Contains apolipoprotein B-100 –> allows them to bind to cells and transfer their lipid (mostly triglyceride) to cells
What is the whole purpose of VLDL in the body?
It transports triglycerides from the liver, to adipose tissue and muscle cells.
Apolipoprotein B-100 allows them to bind to non-hepatic cells.
What is the purpose of LDL?
Deliver cholesterol to non-hepatic tissue
LDL has a _______ rich core and accounts for ___-___ of ________ in the blood.
LDL has a CHOLESTEROL rich core and accounts for 60-70% of CHOLESTEROL in the blood
Since LDL transports cholesterol from the liver to non-hepatic cells, what apolipoprotein does it contain?
Apolipoprotein B-100
Describe the link between LDL cholesterol and atherosclerosis.
There is a clear link between LDL cholesterol and development of atherosclerosis.
The higher the blood LDL level, the greater the risk of developing CHD
How does reducing LDL levels in the blood affect atherosclerosis development?
Reducing LDL levels halts or even reverses atherosclerosis and has been proven to decrease death from CHD
LDL cholesterol is often referred to as what?
Bad cholesterol
What is the role of HDL in the body?
HDL’s deliver cholesterol from non-hepatic tissue back to the liver.
Thus, HDL promotes cholesterol removal from the blood
What is the main core lipid of HDL?
Cholesterol
HDL accounts for __-
__% of total blood cholesterol.
20-30%
Describe the link between HDL and CHD.
Elevated HDL decreases the risk of CHD
What apolipoprotein does HDL contain?
HDL particles may contain multiple apolipoproteins including A-I, A-II and A-IV
Which apolipoprotein from HDL particles mediates their beneficial effects.
A-1 –> allows delivery of cholesterol from non-hepatic cells to the liver
HDL protects against ________ and is thus also called what?
Atherosclerosis
Good cholesterol
The initiation of atherosclerosis begins with what?
Damage to the endothelium
There are many factors that may damage the endothelium, what are they?
HTN, smoking, elevated blood lipids, hemodynamic factors, immune reactions
After damage to the endothelium occurs, what accumulates in the sub-endothelial space?
LDL cholesterol
What occurs to LDL cholesterol that accumulates in the sub-endothelial space?
It may become oxidized
What does oxidation of LDL cholesterol lead to?
Oxidation of LDL cholesterol causes recruitment of monocytes to the sub-endothelial space
Recruitment of monocytes by oxidized LDL particles leads to what?
Conversion of monocytes to macrophages, which ingest oxidized LDL cholesterol. The cells then become larger and vacuolated = foam cells
As foam cells accumulate, a _____ _______ appears.
fatty streak
The formation of a fatty streak is followed by what processes?
Platelet adhesion, smooth muscle migration, and collagen synthesis
What is the end result of LDL accumulation in the sub-endothelial space?
Atherosclerotic lesion characterized by a lipid core and tough fibrous plaque
Although LDL cholesterol plays a critical role in the development of atherosclerosis, it is important to note that atherosclerosis is primarily an __________ process.
inflammatory
Cholesterol screening is recommended for who?
All males over 40, and all females over 50, or females that are post-menopausal
Cholesterol screening is also recommended for people with these conditions/characteristics.
Have diabetes
Have heart disease or a (prominent) family history of heart disease
Have HTN
Have central obesity
Smoke or has recently stopped smoking
Have inflammatory (i.e. arthritis/lupus) or renal disease
_________ ______ assessment is used by HCPs to estimate the risk a patient has of developming CV disease.
CV risk assessment
What is the most commonly used form of CV risk assessment?
Framingham Risk Score
What are the different components used in the FRS to calculate a risk score?
Gender, age, total blood cholesterol, smoking status, HDL cholesterol and systolic BP
The risk score from the FRS represents the patient’s ___ year risk of developing CHD.
Patients with a risk score above __% are considered high risk, between __-___% are considered moderate risk, and below __% are considered low risk.
10 year risk
20%+ - high risk
10-19% - moderate risk
<10% - low risk
It has been shown that the Framingham score tends to ________ the risk in what groups?
underestimate risk in youth, women and pts with metabolic syndrome
Why would we treat low risk (FRS identified) patients?
Because it doesn’t take into account LDL cholesterol levels in the blood
Combination of medical disorders that cause increased risk of CHD and type II diabetes
metabolic syndrome
Metabolic syndrome is diagnosed when patients have three or more of these factors.
1 - Central obesity 2 - Elevated triglycerides 3 - Low HDL cholesterol 4 - Hyperglycemia 5 - HTN
Estimates suggest that __ in ____ Canadians have metabolic syndrome.
Treatment of metabolic syndrome is directed at decreasing the risk for ____ and ________
1 in 4
CHD and type II diabetes
