13. Introduction to Physical Activity and Health

Question 1

what has been the leading cause of death since 1970?

Answer 1

heart disease

Question 2

What are the changeable and unchangeable CVD risk factors?

Answer 2

Unchangeable
- Gender, family, age, race
Changeable
- Smoking, physical activity, obesity, diet/high cholesterol, high BP, inulin resistance

Question 3

Why have risk factors such as smoking, high BP and high cholesterol become less of a risk but factors like obesity and physical activity become higher?

Answer 3

We have evolved to conserve as much energy as possible

Question 4

what is atherosclerosis?

Answer 4

plaque build up in the artery. If the plaque is lower in the coronary tree and it ruptures then there is less risk than if it was higher up the tree and ruptures from a clot

Question 5

Discuss the pathophysiology of atherslerosis

Answer 5

Artery has 3 layer: intima, media and adventitia.

Plaque initiation

• Damage occurs to the vascular endothelium exposes underlying connective tissue.
• Artery wall is infected and inflammatory cytokines are released.
• This recruits white blood cells to the area and will attach - making the plaque.

Plaque Progression

• platelets, endothelial cells and macrophages release growth factors and cytokines that promote migration of smooth muscle cells form the media to the intima.
• As plaque grows, it narrows the arterial opening and impedes blood flow. Lipids in the blood are deposited in the plaque-forming foam cells.

Question 6

Where are plaques usually more often found and why?

Answer 6

More often found near branch points because there is less nitric oxide an this causes adhesion molecules expressed n the endothelial layer to increase, causing white blood cells to be more likely to stick.

Question 7

Outline how lipoproteins are involved in the progression and regression of Atherosclerosis

Answer 7

Chylomicrons, VLDL and LDL are atherogenic. TAG and cholesterol rich.

LDL can move into the intima + become modified which is dangerous - this is proinflammatory. More foam cells and more cytokines

HDL promotes cholesterol efflux (moving back into the blood and preventing foam cells). It also inhibits LDL becoming modified. Inhibits expression of adhesion molecules

Question 8

What apolipoprotein is covering the LDL and HDL?

Answer 8

Apolipoprotein B for LDL

Apolipoprotein A for HDL