Chapter 12 - Antioxidants Flashcards

(41 cards)

1
Q

What are free radical and reactive oxygen species?

A
  • Highly unstable compounds
  • Participate in rxns involving transfer of electrons
  • Initiate and propagate chain reactions leading to molecular-cellular damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are antioxidants?

A

Compounds that neutralize free radicals by donating an electron. They also sequester or bind free radicals or ROS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do free radicals and ROS cause damage to?

A
  • Cell membranes
  • Lipoproteins
  • Proteins
  • Lipids and macromolecules in the cell
  • Genetic material (DNA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cellular damage due to free radicals and ROS contributes to what diseases?

A

Markers for:
* Parkinson’s
* Alzheimer’s
* Coronary artery disease
* Atherosclerosis by diabetes
* Renal disease
* Cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are dietary antioxidants?

A

Nutrient or non-nutrients in foods that significantly decrease adverse effects of free radical & ROS on physiological functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What vitamins are dietary antioxidants?

A

Vitamin E and C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What minerals act as dietary antioxidants?

A

Selenium, Zinc, Copper, and Manganese

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the functions of Vitamin A? (2)

A
  • Lipid digestion and absorption patheways
  • Intracellular transport with retinol-binding protein (RBP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is beta-carotene?

A

Precursor for Vitamin A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are three forms of Vitamin A in the body?

A
  • Retinol (alcohol form)
  • Retinal (aldehyde form)
  • Retinoic acid (acid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What form of vitamin a is found animal foods?

A

Retinyl esters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What form of Vitamin A is found in plant foods?

A

Beta-carotene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What form of vitamin a is involved in bone growth and remodelling?

A

Retinol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

RDA Vitamin A

A
  • Males: 900 RAE/day
  • Females: 700 RAE/day
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is 1 RAE equivalent to?

A

1ug of retinol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How many ug of beta-carotene is equivalent to 1ug of retinol?

A

12ug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Food sources of Vitamin A

A
  • Paprika
  • Yellow/orange fruits and vegetables
  • Dark green ‘’
  • Tomatoes
  • Watermelon
  • Carrots
  • Citrus fruits
18
Q

What is the risk of Vitamin A deficiency?

A
  • Increased incidence of infectious disease
  • Increased risk of measles, malaria, HIV/AIDS
  • Night blindness (lack of retinal in retina)
19
Q

What is the UL for Vitamin A?

A
  • Adults: 3000ug/day
  • Infants: 600ug/day
  • Children: 600-1700 ug/day
20
Q

What is the risk of Vitamin A toxicity?

A

Risk of osteoporosis and fractures.

21
Q

What are the functions of Vitamin E?

A
  • Protects lipids for oxidation
  • Cell membrane stabilization
  • Interacts with other antioxidant mechanisms (Vitamin C)
22
Q

RDA Vitamin E

23
Q

Food sources of Vitamin E

A
  • Sunflower, corn, canola, oilve oil
  • Almonds
  • Pumpkin
24
Q

How does Vitamin E deficieny arise?

A

Rare; more likely due to fat malabsorption rather than low dietary intake

25
What are symptoms of Vitamin E deficiency?
* Hemolytic anemia * Neuromuscular dysfunction Can contribute to: * Cancer * Cardiovascular disease * Cataracts * Alzheimers disease
26
UL Vitamin E
1000mg/day
27
Functions of Vitamin C
* Reducing agent or electron donor in enzymatic rxns * Adrenal gland hormones synthesis * Collagen synthesis * Peptide hormone synthesis
28
RDA Vitamin C
* Males: 90mg/day * Females: 75mg/day Smokers +35mg/day
29
What is Vitamin C deficiency?
Scurvy
30
Symptoms of Vitamin C deficiency
* Anemia * Atheroclerotic plaques * Pinpoint hemorrhages, bone fragility, joint pain * Poor wound healing * Bleeding gums and loosened teeth
31
UL Vitamin C
2000mg/day
32
Symptoms of Vitamin C toxicity
* Nausea, abdominal cramps, diarrhea * Headache, fatigue, insomnia * Hot flashes, rashes
33
Functions of selenium?
* Antioxidant functions with Vitamin E/C and glutathione peroxidase
34
RDA Selenium
55ug/day
35
UL Selenium
400 ug/day
36
Food sources of selenium
* Brazil nuts * Seafood * Organ meats * Beans
37
What is selenium deficiency?
Predisposition to Keshan disease, a heart disease associated with virus
38
Symptoms of selenium deficiency
* Brittle hair and nails * Rash * Fatigue and irritability * Garlic breath odour
39
What is a cofactor for superoxide dimutase?
* Vitamin C * Zinc * Copper
40
What is a cofactor for GSH Peroxidase?
* Vitamin C * Selenium * Iron as catalase
41
Why is it prefered that antioxidants are sourced from food?
Supplements carry an increased risk for CHD, lung cancer, and GI cancer for smokers