Flashcards in Nutrients, Oxidation and Antioxidants Deck (85)
Is vitamin E water or lipid soluble?
Is vitamin C water or lipid soluble?
What is oxidative stress?
O2 will steal an electron from a reduced metal, flavin etc and become superoxide) O2-
Superoxide and its products are known as;
Reactive Oxygen Species or ROS
The gas hormone nitric oxide (NO) is known as a;
Reactive Nitrogen Species (RNS)
How are ROS and RNS formed?
By accident in the electron transport chain
On purpose by immune cells
What can have its structure modified by oxidative or nitrosative stress?
Proteins, lipids, carbohydrates, individual nucleotide bases
Is it good or bad that a hydroxyl group can react with anything around it?
What can aldehydes do that are considered bad?
Create cross links between proteins
How is iron important?
Key role in many enzymes (cytochromes)
Catalysis and electron transfer, oxygen transport
How is iron toxic?
It is insoluble in presence of oxygen
Catalyzes the Haber-Weiss-Fenton Reactions
Produces a free radical hydroxyl
How does iron help defend against the toxins it makes?
With Superoxide dismutase to aid in conversion of superoxide to more stable form
Where and how is iron stored?
In ferritin and hemosiderin mostly in the liver
What molecule moves iron from various organs and cells into tissues and bones?
How much iron should a person have in a day to maintain stores?
At least 8 mg
How is the transferrin receptor complex internalized?
By receptor medicated endocytosis
How is iron release?
How is non-heme iron uptake inhibited?
By phytate and polyphenols in common food (plant sources) like;
- black tea
Polyphenols numerous rings chelate the iron increasing its elimination
How is iron uptake stimulated?
What is a hereditary excess in iron called?
What is a dietary overload of iron called and how can someone get it?
Alcohol (red wines) and over using supplements (children)
What drugs does iron decrease the absorption of?
Thyroxine, tetracyclin, ciprofaloxacin
occurs because numerous rings on the molecules act as chelators and this more effectively eliminates the drug and iron along with it
What is anemia?
Abnormally low blood hemoglobin
What enzymes can protect you from reactive oxygen species?
What chemicals can protect you from ROS?
Bilirubin, glutathione, catalase, vitamin E, B-carotene and ascorbate (vit C)
What is glutathione?
A small tripeptide reversibly oxidized/reduced and can be regenerated by NADPH and glutathione reductase
catalyzes superoxide to hydrogen peroxide
What is the danger in an ischemic/reperfusion injury?
the initial return of oxygen creates a burst of ROS species
Reactive Nitrogen species -RNS
Peroxynitrite is ONOO- which is O2- + NO