lecture 14 - lipoproteins: CVD risk factors Flashcards
Which lipoprotein increases the risk of heart disease?
LDL - low density lipoprotein
What are the atherogenic properties of LDL?
- Has a high affinity to arterial wall (binds to proteoglycans)
- lipids oxidise easily which promotes inflammation then thrombosis
Which cell type becomes foam cells in an atherosclerotic plaque?
Macrophages
What are some of the current interventions for reducing LDL?
Diet, statins, weight loss, exercise
What is the enzyme targeted by statins?
HMG CoA reductase inhibitors
What are the 2 key ways that statins reduce LDL cholesterol levels?
Lower cholesterol synthesis, upregulate LDL receptor
Why do statins not work to treat patients with Familial Hyperchoelsterolaemia?
Statins upregulate LDL receptors, but patients with FH have defective receptors so this doesn’t work
What is Lipoprotein(a)?
A lipoprotein that is essentially modified LDL, and has similar atherogenic effects.
If a patient has genetically elevated Lp(a) levels, is their risk of CVD elevated or reduced?
Elevated
What are the 2 reasons that Lp(a) is a risk factor for CVD?
It is atherogenic, and immunogenic (promotes inflammation)
Can statins be used to treat high Lp(a) levels?
No - Lp(a) does not respond to LDL receptors in the same way.
What are some of the genetic causes of low HDL?
Familial hypoalphalipoporoteinamia, Tangiers Disease
What medical conditions can cause secondary low HDL levels?
Liver disease, TII Diabetes
What is Tangier Disease?
A genetic disease where there is a deficiency of HDL, due to mutations in the ABCA1 cholesterol transporter.
What are the manifestations of Tangier Disease?
Orange tonsils, low HDL, peripheral neuropathy, premature heart disease