Inflammation and Coronary Artery Disease Flashcards
Atherosclerosis
Deposition of plaques of fatty materials on the inner walls of arteries
What underlies the pathogenesis of coronary, cerebral and peripheral vascular disease?
Atherosclerosis
What is a major contributor to the development of atherosclerosis?
INFLAMMATION
What are a few non-modifiable risk factors for atherosclerosis?
Genetics - higher for males (XY)
Family History
Increasing age
What are a few modifiable risk factors for atherosclerosis?
Hyperlipidemia Hypertension Smoking Obesity Chronic inflammation
What are the 5 main steps to the development of atherosclerosis?
- Chronic Endothelial Injury
- Endothelial Dysfunction
- Macrophage activation and Smooth muscle recruitment
- Macrophage and Smooth muscle cells engulf lipids
- Smooth muscle cell proliferation and deposition of collagen and ECM
What are the layers of the blood vessel from superficial to deep?
Endothelium
Intima
Media
Adventitia
What layer of the blood vessel houses the smooth muscle cells?
Media
What causes a chronic endothelial injury?
Risk factors such as hyperlipidemia, hypertension, smoking that induce chronic inflammation that try to repair the damage
Where are the most common areas for development of atherosclerosis and why?
Openings of exiting vessels
Branch points
Posterior abdominal aorta
– Due to flow disturbances (turbulence)
What is the response to the chronic endothelial injury?
Endothelial dysfunction - acute inflammatory response activated
== Increased leukocyte and monocyte adhesion
What immune factors are important in recruiting leukocytes during endothelial dysfunction?
IL-1, IL-6 and TNF
Describe what IL-1 and TNF do in the recruitment of leukocytes?
- Increase expression of P and E selectins on endothelium and the ligands on leukocytes
= Leukocyte ROLLING (bind,detach,bind)
== Leukocyte SLOWS DOWN
What does slowing down of a leukocyte allow?
Allows them to respond to chemokines in the area
What do chemokines do for leukocyte adhesion?
- INCREASE affinity of integrins on the leukocyte for binding
- Leukocytes then attach to the endothelium, flatten and migrate through to the intima
Long term effect of the recruitment of leukocytes?
Changes in hemodynamics in microenvironment
What 4 types of plasma proteins does the inflammatory exudate during endothelial dysfunction bring into contact with the injured area?
- Clotting proteins - clot formation
- Complement proteins - destroy bacteria
- Kinin cascade - increase permeability of blood vessels
- Fibrinolytic proteins - degrade clots
The Endothelial Dysfunction phase activates the Acute inflammatory response. What does this increase the expression of?
Procoagulants
Adhesion molecules
Proinflammatory factors
What are the most common circulating lipids?
Cholesterol and Cholesterol Esters
Describe how Foam Cells are are stimulated via an inflammatory response?
- Circulating lipids (cholesterol and cholesterol esters) deposit and accumulate in the Intima
- Lipids are phagocytosed and modified by macrophages
- Modified LDL accumulated in macrophages and smooth muscle cells
== Stimulates Foam Cell inflammatory response