Role Of Smooth Muscle Cells And Macrophagss In The Pathogenesis Of Atherosclerosis

Question 1

What role do smooth muscle cells play in the development of atherosclerosis?

Answer 1

They are essential for the development of the fibrous lesion (focal intimal thickening)

Question 2

What role do macrophages play in the develpment of atherosclerosis?

Answer 2

Uptake LDLs and become foam cells - have a role in the development of the fibro-fatty plaques

Question 3

Which cells drive the response to injury response?

Answer 3

Smooth muscle cells

Question 4

Summarize the response to injury

Answer 4

Smooth muscle cells migrate to intima, phenotype switch occurs, proliferation of SM cells under PDGF effect, ECM formation - leading to the formation of the focal intimal thickening

Question 5

How do macrophages contribute to atheroma material?

Answer 5

In the presence of hypercholersterolemia, macrophages oxidise and uptake LDLs via scavenger receptors (unregulated), becoming foam cells and continuing to take LDLs in until hey die and contribute to atheroma material of the fibro-fatty plaque

Question 6

Which genes do macrophages which are uptaking LDLs switch on and why?

Answer 6

Genes for cytokines, thus triggeing an inflammatory process which causes further progression of the lesion

Question 7

Is inflammation triggered in the lesion in the absence of hypercholesterolemia?

Answer 7

No