Vitamins Flashcards
What are the water soluble vitamins?
B and C
What are the fat soluble vitamins?
A, D, E, K
Thiamine is important in the formation of coenzyme ________ (TPP)
Thiamine is important in the formation of coenzyme thiamine pyrophosphate (TPP)
What are the names for the following B vitamins?
B1
B2
B3
B6
B9
B12
B1 - Thiamine
B2 - Riboflavin
B3 - Niacin
B6 - Pyridoxine
B9 - Folate
B12 - Cobalamin
Mneumonic: The rhythem nearly proved fully contagious
Vitamin C is also important in ____ absorption
Vitamin C is also important in iron absorption
Vitamin C is also called ________
Vitamin C is also called ascorbic acid
Vitamin C is an ____ and can terminate free radicals and regenerate vitamin E to its ____ form
Vitamin C is an antioxidant and can terminate free radicals and regenerate vitamin E to its antioxidant form
____ decreases absorption of vitamin C
____ decreases tissue vitamin C levels
alcohol decreases absorption of vitamin C
smoking decreases tissue vitamin C levels
Vitamin C (Ascorbic Acid) is required for proper ____ formation
Vitamin C (Ascorbic Acid) is required for proper collagen formation
Note: Collagen is important in skin, bone, cartilage, ligaments, tendons, blood vessel walls, and teeth
A deficiency in vitamin C is called ____
This results in a decrease in ____ production, leading to a decrease in tensile strength, affecting connective tissue, skin, vascular/bone lesions
Symptoms include (3 main examples)
A deficiency in vitamin C is called scurvy
This results in a decrease in collagen production, leading to a decrease in tensile strength, affecting connective tissue, skin, vascular/bone lesions
Symptoms include:
- Swollen/bleeding gums
- Slow wound healing
- Depression
- Joint pain
- Muscle weakness
- Easy bruising
- Fatigue
In scurvy you may also see ____ hairs with ____ around the hair follicles
In scurvy you may also see corkscrew hairs with bleeding around the hair follicles
Scruvy can also cause periungual ____ (bleeding under or around the nails)
Scruvy can also cause periungual hemorrhage (bleeding under or around the nails)
Due to poor nutrition, alcoholics may have a ____ deficiency which decreases transketolase activity (as well as other enzymes that require thiamine)
Due to poor nutrition, alcoholics may have a thiamine deficiency which decreases transketolase activity (as well as other enzymes that require thiamine)
Which enzymes require thiamine?
- Branched chain a-keto acid dehydrogenase complex (MSUD)
- a-ketogluterate dehydrogenase (TCA cycle)
- Pyruvate dehydrogenase (links glycolysis to the TCA cycle)
- Transketolase (HMP shunt)
Mneumonic: Be APT
TPP is needed for the synthesis of what neurotransmitter?
Acetylcholine
Which enzymes require thiamine, lipoic acid, CoA, FAD, and NAD?
- Branched chain a-keto acid dehydrogenase complex (MSUD)
- a-ketogluterate dehydrogenase (TCA cycle)
- Pyruvate dehydrogenase (links glycolysis to the TCA cycle)
Mneumonic: Be AP (similar to Be APT just minus the T)
Vitamin B1 (thiamine) deficiency can result in what syndromes/diseases?
- Beri-Beri disease
- Can be Dry Beri-Beri, Wet Beri-Beri, or Cerebral Beri-Beri
- Wernicke encephalopathy
- Korsakoff syndrome
- Wernicke-Korsakoff syndrome
What causes Beri-Beri disease?
What are the different types of Beri-Beri disease and what are their features?
Thiamine deficiency causes Beri-Beri disease
- Dry (paralytic or nervous) beri-beri
- Main feature is peripheral neuropathy
- Wet (cardiaac) beri-beri
- Rapid heart rate, enlarged heart, edema, difficulty breathing, CHF
- Cerebral beri beri
- May lead to Wernicke encephalopathy and Korsakoff psychosis
Why is it important to give alcoholics thiamine before glucose infusion?
To decrease the risk of Wernicke encephalopathy
Note: Thiamine deficiency causes an ATP depletion. Chronic alcoholics are often hypoglycemic and have a thiamine deficiency
Wernicke-Korsakoff syndrome
Cause
Features
Wernicke-Korsakoff syndrome
Caused by a thiamine deficiency in chronic alcoholics
Features include combination of Wernicke encephalopathy and Korsakoff syndrome:
-
Wernicke encephalopathy:
- Confusion
- Opthalmoplegia (paralysis or weakness of the eye muscles)
- Ataxia (slurred speech, stumbling, incoordination)
- Thiamine deficiency
-
Korsakoff syndrome:
- Retrograde amnesia
- Anterograde amnesia
- Confabulation
- Korsakoff’s psychosis
Mneumonic: COAT RACK
Vitamin __ (aka ____) is needed to make FAD
Vitamin B2 (aka riboflavin) is needed to make FAD
Note: FAD is part of the ETC
Vitamin B2 (Riboflavin) deficiencies are rare but result in what?
- Dermatitis
- Cracked and red lips
What are two enzymes that are FAD-dependent (Thus riboflavin/B2 dependent)
- Glutathione reductase
- Xanthine oxidase
____ is needed to make NADH which is required in glycolysis, gluconeogenesis, TCA, and fatty acid oxidation.
It is also needed to make NADPH which is used in the pentose phosphate pathway
Glycogen synthesis does not utilize NAD or NADPH
Niacin (vitamin B3) is needed to make NADH which is required in glycolysis, gluconeogenesis, TCA, and fatty acid oxidation.
It is also needed to make NADPH which is used in the pentose phosphate pathway
Glycogen synthesis does not utilize NAD or NADPH
Niacin is used to make ____, ____, and ____. The first of which is an ________ that participates in oxidation-reduction reactions by accepting a ________ and becoming ____ (the reduced form)
Niacin is used to make NAD+, NADH, and NADPH. NAD+ is an oxidizing agent that participates in oxidation-reduction reactions by accepting a hydride ion (H-) and becoming NADH (the reduced form)
Niacin (Vitamin B3) deficiency results in ____ which has the following characteristics (4 examples):
Uncommon in the U.S, but sometimes found in ____ due to decreased niacin absorption with ____ ingestion
Niacin (Vitamin B3) deficiency results in Pellegra which has the following characteristics (4 examples):
- Dermatitis
- Diarrhea
- Dementia
- Death (if untreated)
Note: Pellegra has the 4 D’s
Uncommon in the U.S, but sometimes found in alcoholics due to decreased niacin absorption with alcohol ingestion
Folic Acid (Vitamin B9) is reducted to its active form ____
One of the “one carbon” donors in biosynthesis needed for purine nucleotide ssynthesis, thymine sythensis, and methionine synthesis from homocysteine
Essential ____ vitamin required for closure of neural tube in fetal development to prevent spina bifida
Folic Acid (Vitamin B9) is reducted to its active form tetrahydrofolate (THF)
One of the “one carbon” donors in biosynthesis needed for purine nucleotide ssynthesis, thymine sythensis, and methionine synthesis from homocysteine
Essential prenatal vitamin required for closure of neural tube in fetal development to prevent spina bifida
Folic acid (vitamin B9) deficiency results in (3 main examples):
Folic acid (vitamin B9) deficiency results in:
- Macrocytic anemia
- Glossitis
- Hypersegmented neutrophils
- Sore mouth, diarrhea, weight loss, heartburn, constipation
Methylmalonyl CoA Mutase requires vitamin ____
Deficiency can lead to elevated levels of ________ which causes metabolic acidosis and ____ problems
Methylmalonyl CoA Mutase requires vitamin B12
Deficiency can lead to elevated levels of methylmalonic acid which causes metabolic acidosis and developmental problems
Cobalamin (Vitamin B12) is required for which to enzymatic reactions?
- Methionine Synthase (converts homocysteine to methionine)
- Methylmalonyl CoA Mutase (converts methylmalonyl CoA to Succinyl CoA)
- Note methylmalonyl CoA is produced during degredation of FAs with an odd number of carbons and via the degredation of some AAs
Cobalamin (Vitamin B12)
Deficiency most commonly seen in patients who fail to absorb B12
________ is required to absorb B12
Cobalamin (Vitamin B12)
Deficiency most commonly seen in patients who fail to absorb B12
Intrinsic Factor is required to absorb B12
B12 deficiency due to a lack of intrinsic factor leads to ____ anemia (a form of megaloblastic anemia)
Deficiency in intrinsic factor can occur from lack of functional parietal cells (e.g. stomach damage or surgery)
B12 deficiency can also be caused by a diet lacking ____ (common in ____ and ____)
B12 deficiency due to a lack of intrinsic factor leads to pernicious anemia (a form of megaloblastic anemia)
Deficiency in intrinsic factor can occur from lack of functional parietal cells (e.g. stomach damage or surgery)
B12 deficiency can also be caused by a diet lacking meat (common in vetarians and vegans)
B12 deficiency symptoms (2 main examples):
- Megaloblastic anemia
- Neurologic symptoms (irreversable)
Note: Some symptoms can be relieved with folate but the nerve damage can not be reversed
Vitamin B9 (Folate) Defiency vs Vitamin B12 (Cobalamin) Defiency
HCT
MCV
Homocysteine
Methylmalonic Acid
Neurological Symptoms
Biotin is required for ____ reactions
Biotin is required for carboxylation reactions
Biotinidase deficiency can result in a functional biotin deficiency
A biotin defiency can result in (4 main examples):
Biotinidase deficiency can result in a functional biotin deficiency
A biotin defiency can result in:
- Hair/scalp problems (inoperative acetyl-CoA carboxylase leads to inability to synthesize FAs)
- Impaired gluconeogenesis, excess pyruvate converted to lactate, increased ketone bodies (inoperative pyruvate carboxylase)
- Elevated propionic acid (inoperative priorionyl-CoA carboxylase)
- Optic atrophy (possibly d/t lack of energy d/t reduced gluconeogenesis, or inability to synthesize FAs within neurons)
Vitamin A is important for ____ which is a component of the visual cycle
Vitamin A is important for 11-cis-retinal which is a component of the visual cycle
Vitamin A acts on ____ receptors
Vitamin A acts on nuclear receptors
Vitamin A deficiency can lead to ____ spots (usually accompanied by night blindness) on the eye which can develop into ____ if not treated
Vitamin A deficiency can lead to bitot spots (usually accompanied by night blindness) on the eye which can develop into xerophthalmia if not treated
Vitamin A deficiency is the leading cause of preventable ____ in children and increases the risk of disease/death from severe ____
Vitamin A deficiency is the leading cause of preventable blindness in children and increases the risk of disease/death from severe infections
Vitamin A deficiency causes:
Vitamin A deficiency causes:
- Night blindness
- Bitot spots on eye –> can progress to xerophthalmia –> blindness
- Follicular hyperkeratosis
Newborns are usually give an injection of vitamin __ to prevent hemorrhagic diseases
Newborns are usually give an injection of vitamin K to prevent hemorrhagic diseases
Functions of vitamin K (2 main examples)
Functions of vitamin K:
- Blood clotting
- Vitamin K-dependent y-carboxylation is essential to the activity of factor II, VII, IX, and X, as well as protein C and S
- Skeletal formation and prevention of soft tissue calcification
- Vitamin K-dependent y-carboxylation is essential to several bone-related proteins, including osteocalcin
Causes of Vitamin K deficiency (3 main examples)
Causes of Vitamin K deficiency:
- Biliary tract disease interfering with enterohepatic circulation, leading to decreased absorption of vitamin K
- Drugs, especially antibiotics, that sterilize the gut and reduce bacterial sources of vitamin K, or other drugs (cholestyramine) that directly block vitamin K absorption
- Poor nutritional status induced by malabsorption, chronic disease, or poor oral intake in acutely ill patients
Vitamins D2 and D3 are first converted to calcidiol and then to ____ (the active vitamin D)
Note: 7-dehydrocholesterol (provitamin D3) is decreased in the skin of older adults
Vitamins D2 and D3 are first converted to calcidiol and then to calcitriol (the active vitamin D)
Note: 7-dehydrocholesterol (provitamin D3) is decreased in the skin of older adults
Vitamin D is also called ____
It’s absorbed in the intestinal ileum and requires bile salts. D3 can be made in our own skin in the presence of ____
Vitamin D is converted into its active form ____ in the liver and kidneys
Vitamin D is also called cholecalciferol
It’s absorbed in the intestinal ileum and requires bile salts. D3 can be made in our own skin in the presence of sundlight
Vitamin D is converted into its active form calcitriol in the liver and kidneys
Vitamin D function
Acts as a hormone to regulate calcium and phosphate:
- Increases absorption of calcium and phosphate in the intestines
- Increases reabsorption of calcium and phosphate in the kidneys
- Stimulates release of calcium and phosphate from bone when calcium and phosphate levels are low
When calcium levels are low, parathyroid hormone (PTH), stimulates 25-hydroxycholecalciferol in the liver and 1-hydroxylase in the kidney to produce ____
When calcium levels are low, parathyroid hormone (PTH), stimulates 25-hydroxycholecalciferol in the liver and 1-hydroxylase in the kidney to produce calcitriol (the active form of vitamin D)
Vitamin D deficiencies can be caused by:
Vitamin D deficiencies can be caused by:
- Lack of sunlight (Cloudy climates/excessive clothing or body covering/etc.)
- Prolonged nursing in infants
- No milk or unsupplemented bovine milk
- Poor diets of older adults (need for multivitamins or improved diet)
Vitamin D deficiency symptoms
Vitamin D deficiency symptoms:
- Bone pain
- Rickets (weakening of bones in children)
- Bowing of femurs
- Decreased bone opacity
- Beaded ribs
Vitamin E (tocopherol)
Function
Deficiency
Vitamin E (tocopherol)
Function: antioxidant (free radical scavenger); protects membranes/lipoproteins from oxidative damage
Deficiency: Very rare; seen in those who poorly absorb fat. Can cause eye problems due to oxidative stress.
Summary of Vitamin Storage
Liver stores large quantities of vitamin __ (10 months), __ (>1 year), and __ (3-4 months)
Storage of most water-soluble vitamins is ________
Clinical symptoms of the __ vitamins deficiencies (except __) can sometimes be recognized within a few days and vitamin __ deficiency within a few weeks
Summary of Vitamin Storage
Liver stores large quantities of vitamin A (10 months), B12 (>1 year), and D (3-4 months)
Storage of most water-soluble vitamins is relatively short
Clinical symptoms of the B vitamins deficiencies (except B12) can sometimes be recognized within a few days and vitamin C deficiency within a few weeks
