Biochemistry: Vitamins

Front 1

What type of vitamins are most toxic?

Back 1

Fat-soluble since they accumulate in the fat

Front 2

What causes fat-soluble vitamin deficiencies

Back 2

Cystic fibrosis and sprue

Front 3

What vitamins don't wash out of the body?

Back 3

Vitamin B-12 and Folate

Front 4

What do B-Complex deficiency often cause?

Back 4

dermatitis, glossitis, and diarrhea

Front 5

What does Vitamin A deficiency cause?

Back 5

Night blindness, dry skin

Front 6

What is the precursor of Vitamin A (2) and how is it stored?

Back 6

Retinol and Beta Carotene, Chylomicron to the liver released when needed

Front 7

Name two Vitamin B1 deficiencies?

Back 7

Beriberi and Wernicke-Korsakoff syndrome

Front 8

What is the function of Vitamin B1? (2)

Back 8

Cofactor for which helps with Pyruvate dehydrogenase conversion of pyruvate->Acetyl Coa, Cofactor for transketolase in the HMP shunt

Front 9

Name the precursor of Vitamin B1, B2, B5, B6, B12

Back 9

TuRN Pe Pe Color, Thiamine, Riboflavin, Niacin, Pantothenate, Pyridoxine, Cobalamin

Front 10

What happens in a deficiency of Vitamin B2?

Back 10

Riboflavin, get Corneal Vascularization, Cheilosis( Inflammation of the lips), Angular stomatitis (inflammation of the oral mucous lining)

Front 11

What is Vitamin B2's function?

Back 11

Cofactor in oxidation and reduction (FAD- Cofactor associated with succinate dehydrogenase in the citric acid cylcle succinate--> fumirate)

Front 12

What is the function of Vitamin B3 cause? What is it derived from?

Back 12

Makes up NAD and NADP, Derived from tryptophan using Vitamin B6

Front 13

What is a deficiency of Vitamin B3 called and its symptoms?

Back 13

Pellagra- Diarrhea, Dementia, Dermatitis

Front 14

What is Pellagra caused by?

Back 14

Deficiency of Niacin is made by Tryptophan
Hartnup disease (decrease tryptophan absorption since defect in absorption of neutral amino acids), Malignant carcinoid syndrome (increase tryptophan Metabolism since making serotonin), INH (decrease vitamin B6) since caused by lack of Vitamin B3 which is derived from tryptophan with the help of B6

Front 15

What is Vitamin B5 a component of?

Back 15

Component of Fatty acid synthase and CoA (a cofactor for acyl transfer)- Panthothenate

Front 16

What happens in B6 deficiency? What type of patients get it?

Back 16

Either alcoholics or people with Isoniazid therapy for tuberculosis. Convulsion, Hyperirritablity, and peripheral neuropathy.

Front 17

What is the function of B6?

Back 17

A.Required for synthesis of Niacin from tryptophan.
B. Converteed to pyridoxal phosphate a cofactor used in transamination (ALT and AST)

Front 18

How is a deficiency of B12 caused by? What are the symptoms?

Back 18

Caused by pernicous anemia (autoimmune destruction of parietal cells) causes Macrocytic anemia, and neurologic symptoms

Front 19

How does B12 make it to the body?

Back 19

Intrinsic factor made by the parietal cells attach to B12 and they get absorbed in the Illeum where it is stored in the liver for years.

Front 20

What is the function of B12?

Back 20

A. Used as a cofactor to transfer the methyl group making homocysteine to Methoinine
B. Can also be used in odd chain fatty acid synthesis for Methymalonyl-Coa-> Succinyl-Coa

Front 21

How do you get Folic acid in diet? When is folic acid espescially needed?

Back 21

Get folic acid from green leaves (foliage), espescialy useful in pregnant women helps prevent neural tube defects.

Front 22

What happens in Folic acid deficiency?

Back 22

Neural tube defect in pregnancy but can cause Macrocytic anemia but no neurologic problems ( as oppossed to B12); small supply 3-4 months.

Front 23

What is folic acid's function?

Back 23

A.Helps in DNA replication since important for synthesis of nitrogenous bases
B. Coenzyme (THF) for 1-carbon transfer; involved in methylation reaction

Front 24

How do you get Biotin Deficiency?

Back 24

Biotin is made by bacteria in intestines when given antibiotics causes deficiency or
B. If eat raw eggs will bind to the biotin

Front 25

What happens in biotin deficiency?

Back 25

Dermatitis and enteritis (inflammation of small intestines)

Front 26

What is the function of Biotin?

Back 26

Cofactor for carboxylation:
A. Pyruvate -> oxaloacetate
B. Acetyl-Coa--> Malonyl-Coa
C. Propionyl-Coa-> Methylmalonyl coa

Front 27

what happens in Vitamin C deficiency?

Back 27

Scurvy- swollen gums, bruising, anemia, poor wound healing

Front 28

Function of vitamin C? (4)

Back 28

A. Hydroxylation of proline and lysine in collagen synthesis
B. Keeps Iron in reduced state (+2) to make them more absorbable
C. Cofactor for dopamine beta-hydroxylase which converts dopamine to NE
D. Keeps tetrahydrofolate (FH4) in reduced state

Front 29

What does an excess of Vitamin C cause?

Back 29

Renal Calculi

Front 30

What does a deficiency of Vitamin D cause?

Back 30

A. Rickets in children (bending bones)
B. Osteomalacia in adults (soft bones)
C. hypocalcemic tetany

Front 31

What is the function of Vitamin D?

Back 31

increase intestinal absorption of Calcium and Phosphate.

Front 32

Where do you get Vitamin D?

Back 32

D2=ergocalciferol (Milk)
D3= cholecalciferol (sun-exposed skin) gets converted from 7-Dehydrocholesterol

Front 33

What is the storage form and active form of D3? how are they converted?

Back 33

25-OH D3 is the storage form and is converted to active form (1,25 (OH)2 D3) by 1-alpha hydroxylase which is in the kidney and enhanced by PTH. Makes sense b/c PTH and Vitamin D help maintain Ionized calcium levels

Front 34

How can you get Vitamin D excess and what happens?

Back 34

In sarcoidosis the macrophages convert Vitamin D to its active form causing Hypercalcemia and loss of appetite

Front 35

What is the function of Vitamin E?

Back 35

Protects erythrocytes from hemolysis

Front 36

How does Vitamin K work?

Back 36

Catalyzes gamma-carboxylation of glutamic acid in the liver its release and binds to calcium which is essential for formation of the clot

Front 37

What vitamins are neonates given?

Back 37

Since neonates have sterile intestines they don't make vitamin K so they get it to prevent hemmorhage

Front 38

What happens in Zinc Deficiency?

Back 38

Delayed wound healing, hypogonadism, decrease adult hair, and may predispose to alcoholic cirrhosis

Front 39

What does Disulfram do?

Back 39

inhibits acetaldehyde dehydrogenase so acetaldehyde accumulates contributing to hangover symptoms used for alcoholics

Front 40

Alcohol metabolism

Back 40

Ethanol (alcohol dehydrogenase-cytosol) -->acetaldehyde (acetaldehyde dehydrogenase-mitochondria)-->acetate
In both reaction NAD is the limiting reagent

Front 41

What does Fomepizole do?

Back 41

Inhibits alcohol dehydrogenase

Front 42

How is ethanol hypoglycemia caused by?

Back 42

In alcohol metabolism a large amount of NADH is accumulated this causes the pyruvate--> lactate and oxalolacetate--> malate which leads to less glycolysis and more fatty acid synthesis (Altered NADH/NAD+ ratio)

Front 43

What is the difference between Kwashiorkor and Marasmus?

Back 43

Kwashiorkor- (MEAL) protein malnutrition, Edema, Anemia, Liver malfunction
Marasmus-energy malnutriton causing tissue and muscle wasting; loss of subcutaenous fat and variable edema