Metab2: T3 Vitamin C
name the four symptoms of scurvy
4H's hemorrhagic signs hyperkeratosis of hair follicles hypochondriasis hematologic abnormalities
Vitamin C functions as a(n) ___ by reversing oxidation by donating electrons and hydrogen atoms
antioxidant
Endogenous Vitamin C is involved in the synthesis of ___ from cholesterol
bile acids
Oxyradicals contribute to formation of ____
cataracts
A (deficiency/toxicity) of vitamin C will cause scurvy
deficiency
High intakes of vitamin C may decrease ___ and macular degneration
cataracts
Xenobiotics undergo reactions using monooxygenases and ____. These reactions require Vitamin C as a reducing agent
cytochrome P450
At risk populations for a deficiency in vitamin C include those people with poor ___
diets
Very little evidence is out there to show that taking vitamin C will decrease a cold's ___
duration
In the most general sense, the function of Vitamin C as it is used in the body is to donate ___ and ___
electrons and hydrogen ions
Large amounts of iron may (enhance/inhibit) absorption of vitamin C
inhibit
Large doses of vitamin C are not recommended for people who have impaired ___ function
kidney
Large doses of vitamin C may increase the risk of ___
kidney stones
Vitamin C helps with getting rid of ___, which contribute to formation of cataracts
oxyradicals
Vitamin C is absorbed via GLUT transporter or ____
passive diffusion
Vitamin C functions as an antioxidant in blood or intracellularly by giving ___ an electron (hydrogen ion)
radicals
A deficiency in vitamin C is (rare/common)
rare
A toxicity in vitamin C is (rare/common)
rare
Vitamin E and glutathione reduce ____ ... aka eliminate free radicals
reactive oxygen species
A deficiency of vitamin C will cause what is known as ___
scurvy
Vitamin C functions as a pro-oxidant by reducing ____
transition metals
High intakes of vitamin C, greater than 12 g, result in a ___% absorption
16%
Vitamin C intakes of 1.5g daily for __ months, decreased ceruloplasmin
2
Name the sources of vitamin C:
Citrus, Broccoli, Brussels sprouts, green peppers, cantaloupe, strawberries, papaya and supplements
Vitamin C is involved in ____ , ____ and ___ synthesis
Collagen, Carnitine and Catecholamine synthesis
Carnitine synthesis involves Vitamin C working together with Fe, while catecholamine synthesis involves working together with ___
Copper
Carnitine synthesis requires both ___ and ___ for 2 steps
Fe and Vit C
Vitamin C puts ___ into digestible form, but that puts vitamin C into a poor form
Fe iron
Vitamin C is absorbed via ___ or passive diffusion
GLUT transporter
(increased/decreased) vitamin C intakes are associated with lower risk of heart disease and stroke
Increased
Catecholamine synthesis involves working together with Copper, while Carnitine synthesis involves working together __
Iron
The main form of vitamin C that is found in supplements is ____
free ascorbic acid
Dehydroascorbic acid and ascorbic acid are actually absorbed by ___ receptors since they're so similar in form
glucose
Vitamin C closely resembles ___
glucose
Vitamin C has a (high/low) UL
high
Regarding assessment of vitamin C, leukocyte levels are (direct/indirect)
indirect
(high/low) vitamin C status has been correlated with increased blood total cholesterol concentrations
low
Increased vitamin C intakes are associated with (higher/lower) risk of heart disease and stroke
lower
Vitamin C functions as an antioxidant by reversing ___ by donating electrons and hydrogen atoms
oxidation
In carnitine synthesis, enzymes serve to (oxidize/reduce) iron
oxidize
As a pro-oxidant, Vitamin C is ___ to semi-dehydroascorbate
oxidized
Dopamine monooxygenase (oxidizes/reduces) Cu+ to Cu2+
oxidizes
For assessment of vitamin C, ___ will only tell you if the levels are very high or very low
urinary excretion
Fruits and vegetables are high in ___
vitamin C
Vitamin C is involved in synthesizing ___ from dopamine
Norepinephrine
___ is characterized by impaired hydroxyproline and hyroxylysine synthesis (needed for collagen formation)
Scurvy
During collagen synthesis, Iron is converted from ferric to ferrous form by ____
Vitamin C
When Vitamin C functions as a pro-oxidant, ___ is oxidized to semi-dehydroascorbate
Vitamin C
Xenobiotics undergo reactions using monooxygenases and cytochrome P450. These reactions require ____ as a reducing agent
Vitamin C
Vitamin C regenerates ___ and ___
Vitamin E and Glutathione
Drugs, carcinogens, food additives and pollutants are examples of ____
Xenobiotics
____ undergo reactions using monooxygenases and cytochrome P450. These reactions require Vitamin C as a reducing agent
Xenobiotics
Endogenous Vitamin C is involved in the synthesis of bile acids, as well as ___ and ___
aldosterone and coristol
Vitamin C functions as a(n) ___ in blood or intracellularly by giving radicals an electron (hydrogen ion)
antioxidant
Vitamin C functions as an antioxidant by regenerating other ___
antioxidants
Vitamin C was the first vitamin to be ____
artificially made in a lab
Vitamin C is also known as ____ acid
ascorbic acid
The two forms of Vitamin C are ___ and ___
ascorbic acid and dehydroascorbic acid
4-butyrobutaine becomes carnitine via the enzyme ____
butyrobutaine hydroxylase
At risk populations include people with ___, increase turnover rate
cancer
Increased intakes of fruits and vegetables are linked with decreased risk of some ___
cancers
The job of ___ is to transport fatty acids from the cytosol to mitochondria for B-oxidation
carnitine
Vitamin C intakes of 1.5g daily for 2 months, decreased _____
ceruloplasmin (copper)
Low vitamin C status has been correlated with increased blood total ___ concentrations
cholesterol
Adequate levels of vitamin c may help prevent a __
cold
Scurvy is characterized by impaired hydroxyproline and hyroxylysine synthesis (needed for ___ formation)
collagen
___ synthesis involves the conversion of proline to hydroxyproline
collagen
People who have alcoholism and drug abuse are at risk for a vitamin C (deficiency/toxicity)
deficiency
Regarding assessment of vitamin C, serum and urinary are (direct/indirect)
direct
Norepinephrine is synthesized from dopamine using the enzyme ___
dopamine monooxygenase
_____ is the enzyme that oxidizes Cu+ to Cu2+ during catecholamine synthesis
dopamine monooxygenase
Name examples of xenobiotics:
drugs, carcinogens, food additives and pollutants
At risk populations for a deficiency in vitamin C include the (elderly/young)
elderly
Vitamin C functions as an antioxidant in blood or intracellularly by giving radicals a(n) ___
electron (hydrogen ion)
Vitamin C functions as an antioxidant by reversing oxidation by donating ___ and hydrogen atoms
electrons
Ascorbate will (enhance/inhibit) the absorption of non-heme iron
enhance
The job of carnitine is to transport ___ from the cytosol to mitochondria for B-oxidation
fatty acids
At risk populations for a deficiency in vitamin C include the elderly because they don't eat a lot of ___
fruits and vegetables
In general, the best sources of vitamin C are __ and __
fruits and vegetables
Vitamin C is synthesized from glucose or ___ in most animals and plants
galactose
Humans cannot synthesize Vitamin C because we lack the enzyme ___
gluconolactone oxidase
Vitamin C is synthesized from ___ or galactose in most animals and plants
glucose
This symptom of scurvy is associated with impaired iron absorption
hematologic abnormalities
This symptom of scurvy is characterized by bleeding gums, and petechia
hemorrhagic signs
___ are on of the few mammals unable to synthesize Vitamin C due to the lack of the enzyme gluconolactone oxidase
humans
Collagen synthesis involves the conversion of proline to ___
hydroxyproline
Scurvy is characterized by impaired ___ and hyroxylysine synthesis (needed for collagen formation)
hydroxyproline
One symptom of scurvy is ___ of the hair follicles, especially on the arms, legs and buttocks
hyperkeratosis
This symptom of scurvy is characterized by psychological manifestations
hypochondriasis
Scurvy is characterized by (impaired/increased) hydroxyproline and hyroxylysine synthesis (needed for collagen formation)
impaired
Low vitamin C status has been correlated with (increased/decreased) blood total cholesterol concentrations
increased
Large amounts of ___ may inhibit absorption of vitamin C
iron
For assessment of vitamin C, vitamin C is found in high levels in ___
leukocytes
Vitamin C's anti-scurvy properties were first shown through prescription of __ juice to the british navy
lime
High intakes of vitamin C may decrease cataracts and ____ degeneration
macular
Vitamin C acts as a reducing agent during ___ metaboism
microsomal
Xenobiotics undergo reactions using ____ and cytochrome P450. These reactions require Vitamin C as a reducing agent
monooxygenases
Name the cancers positively associated with increased intakes of fruits and vegetables:
mouth, throat, stomach, lung, colorectal
Ascorbate will enhance the absorption of (heme/non-heme) iron
non-heme
___ contribute to formation of cataracts
oxyradicals
The ___ diet in its strictest form, puts people at risk for a deficiency in vitamin C
paleo
___ is pin point hemorrhages underneath the skin
petechia
As a ___, Vitamin C is oxidized to semi-dehydroascorbate
pro-oxidant
Vitamin C functions as a(n) ____ by reducing transition metals
pro-oxidant
Collagen synthesis involves the conversion of ____ to hydroxyproline
proline
During collagen synthesis, Iron is converted from ferrous to ferric form by ____
prolyl hydroxylase
_____ is when someone is continuously on high doses of vitamin C. Once they stop the high doses, their body thinks it is deficient instead of at normal levels.
rebound scurvy
In both steps of Carnitine synthesis, Vitamin C is used to (oxidize/reduce) iron
reduce
Vitamin C acts as a(n) (oxidizing/reducing) agent during Microsomal metabolism
reducing
Vitamin C functions as a pro-oxidant by (reducing/oxidizing) transition metals
reducing
Xenobiotics undergo reactions using monooxygenases and cytochrome P450. These reactions require Vitamin C as a (oxidizing/reducing) agent
reducing
As a pro-oxidant, Vitamin C is oxidized to ___
semi-dehydroascorbate
Regarding assessment of vitamin C, __ and ___ are direct
serum and urinary
For assessment of vitamin C, __ levels are the most common way of assessment
serum levels
Symptoms of vitamin c (deficiency/toxicity) are diarrhea and abdominal pain
toxicity
Toxicity of vitamin C is not common since it is ___ soluble
water
Low intakes of vitamin C, less than 20mg, result in a ___% absorption
98%
