CVD

Question 1

Causes of high levels of homocysteine (7)

Answer 1

Vitamin deficiencies 
High methionine consumption 
Age
Male
Smoking
Physical inactivity 
Diabetes and renal disease

Question 2

How may homocysteine trigger atherosclerosis (4)

Answer 2

Stimulates VSMC to proliferate in vessel wall
Promotes blood clotting
Increases circulating lipids
Oxidises to hydrogen peroxide and superoxide in the presence of free iron and copper

Question 3

What may Homocysteine be an indicator of?

Answer 3

Oxidative stress

Question 4

How may folate protect against CVD (2)

Answer 4

Protect LDL against oxidation

Stimulates nitric oxide release and healthy endothelial function

Question 5

Main characteristics of atherosclerosis (6)

Answer 5

Monocytes migrate into the arterial wall

And differentiate into macrophages

Cholesterol is take up by macrophages

Increased amounts of extracellular matrix compounds are deposited in the wall

Smooth muscle cell proliferation

Apoptosis of macrophages

Question 6

Tocopherol (vitamin E) (3)

Answer 6

Major antioxidant in fats
Chain-breaking free radical scavenger
Removal of free radicals results in formation of tocopheroxyl radical

Question 7

Fat soluble antioxidants (4)

Answer 7

Alpha-tocopherol
Ubiquinone
Beta carotene
Lycopene

Question 8

How may polyphonels reduce CHD risk?(4)

Answer 8

Increased vasodilation
Reduced platelet aggregation
Down regulation transcription factors and genes which promote inflammation and endothelial dysfunction
Inhibit cytokine signalling to reduce inflammation

Question 9

Main confounding factor of CHD and antioxidants

Answer 9

Social class

Question 10

When do antioxidants seem most effective

Answer 10

When consumed in natural sources

Question 11

Atherosclerosis (4)

Answer 11

Disease that affects arteries

Characterised by thickening of the artery wall

Due to accumulation of smooth muscle cells, macrophages deposits of extracellular matrix

Question 12

Inherited disorders of homocysteine metabolism (4)

Answer 12

Raised plasma homocysteine
Premature atherosclerotic and thrombotic disease
Endothelial injury within vasculature
Vascular smooth muscle proliferation

Question 13

Vitamin supplements that reduce homocysteine (3)

Answer 13

B12
B6
Folate

Question 14

Diet and homocysteine (3)

Answer 14

Diet can modify the genetically high homocysteine
Lowering homocysteine are beneficial for stroke prevention
Does not reduce CVD risk

Question 15

Reasons why studies don’t show folate didn’t reduce risk of CVD (3)

Answer 15

All trials of folate and CVD tend to use people with disease, healthy people may respond differently
May need higher dosage, not just dose to reduce homocysteine
May not be cardio-protective

Question 16

Sodium sensitive characterisation

Answer 16

Blood pressure falls by 3 mmHg with dietary sodium

Question 17

Salt resistance characterisation

Answer 17

Increased in blood pressure in response to salt reduction

Question 18

Vitamin E and CHD (4)

Answer 18

MI patients shown lower beta carotene
MI patients have lower fat soluble antioxidants overall
Supplementation does not reduce CV death
But does reduce risk of non fatal MI

Question 19

Sodium sensitivity (2)

Answer 19

Blood pressure falls by 3 mmHg with dietary sodium restriction
And rises the same degree with sodium loading