Water-Soluble Vitamins

Vitamin B complex and Vitamin C

What are the water-soluble vitamins?

portal system (liver)

Water soluble vitamins are transported actively or passively in the _____

F

T or F: Water soluble vitamins are stored in body organs and tissues

Body pool

Refers to the total amount of a specific nutrient or substance available for use in the body — requires constant replacement via diet

Vitamin B

• 8 compounds with dissimilar properties

• “Energy-releasing vitamins”, involved in ATP production

• Hematopoietic vitamin

Thiamine

Vitamin B1

Vitamin B1 (Thiamine)

• Component of coenzyme Thiamine pyrophosphate (TPP)

• TPP — necessary for decarboxylation of alpha keto acids

  • critical to transformation of CHO, proteins, and lipids into energy

Thiamine pyrophosphate (TPP)

Vitamin B1 (Thiamine) functions as a component of essential coenzyme _____

Thiamine pyrophosphate (TPP)

Necessary for decarboxylation of alpha keto acids

ACh

Thiamine is also required in the synthesis of _____

active transport

Vit B1 is absorbed by _____ in the portal circulation

muscles

Where is majority of vit B1 found?

Whole and enriched grains

Best sources of Vit B1

• Dry beans

• Peas

• Vegetables (potatoes)

• Lean pork (high amount)

Sources of Vit B1

Beri beri

Classic thiamine deficiency seen in malnourished, homeless people

Wernicke-korsakoff syndrome

Classic thiamine deficiency seen secondary to alcohol abuse (when you abruptly stop alcohol)

Beri beri

• Fatigue, irritability, depression, loss of appetite

• Adult symptoms:

  • indigestion

  • constipation

  • headaches

  • rapid heart rate

  • numbing effect

  • weakness of legs

• Edema, eventual liver failure

Riboflavin

Term for Vitamin B2

Vitamin B2 (Riboflavin)

• Unique, yellow green fluorescent pigment

• Faint green tinge seen in skim milk

  • In foods, these color pigments are designated as “flavins”

heat

Vit B2 is stable in _____

Vitamin B2

Main constituent of enzymes Riboflavin monophosphate and flavin adenine dinucleotide (FAD)

Riboflavin monophosphate, Flavin adenine dinucleotide (FAD)

Vit B2 is a main constituent of these enzymes:

active transport

Vit B2 is absorbed by _____

Vitamin B2

Excreted into the urine which takes a bright orange-yellow color

0.6mg/1000 cal per day

RDA for Vitamin B2

• Milk and to a lesser extent in plants

• Added to refined flour during enrichment process

Vit B2 sources

Vitamin B2 deficiency

• Growth failure

• Greasy scaliness of skin around nose and ears

• Eye fatigue, itching, burning, water, and extreme sensitivity to bright light

• Increased capillary blood vessels in the cornea = “blood shot appearance”

Chloramphenicol

Medication associated with riboflavin deficiency

Niacin

Term for Vitamin B3

Nicotinamide, nicotinic acid

Niacin is the general term applied to 2 active forms:

Niacin

Component of coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP)

NAD and NADP

Niacin is a component of coenzymes _____

• coenzymes for the release of energy from macronutrients

tryptophan

The body is able to transform _____ into niacin

6.6 mg/1000 cal

RDA for Vit B3

tryptophan conversion ; diet

Half of total niacin is obtained from _____, other half is from _____

Meat, fish, poultry

Sources of Vit B3

Pellagra

Disease of 4 “Ds”

• Diarrhea

• Dermatitis

• Dementia

• Death

Vitamin B3 deficiency (Pellagra)

• Swollen, sore, smooth, scarlet red-colored tongue

• Symmetrical dermatitis - sensitivity to sun

• Evident mental changes — dementia, delirium, depression, disorientation

• w/o treatment can lead to death

• Angular cheilosis (lip fissures)

• Stomatitis (inflammation of mouth corners)

• Secondary infection with fungi or bacteria leading to ANUG (acute necrotizing ulcerative gingivitis)

Vitamin B3 excess

• Toxic effects from food not recorded

• Toxicities shown from use of nicotinic acid for heart diseases

  • heart burn, gastric ulcers, elevation of blood glucose levels

Vitamin B1, B2, B3

What are the energy-releasing vitamins?

Vitamin B6, B9, B12

What are the hematopoietic vitamins?

Pyridoxamine

Term for Vitamin B6

Vitamin B6 (Pyridoxamine)

• Group of related compounds — pyridoxine, pyridoxal, pyridoxamine

• Main function: Involved in protein metabolism

• Constituent of the coenzyme pyridoxal phosphate (PLP)

• Needed for normal devt and function of RBCS

Pyridoxal phosphate (PLP)

Vit B6 is a constituent of the coenzyme _____

All plant and animal sources except sugar and fat

Vit B6 sources

Vitamin B6 deficiency

• Irritability, depression, confusion, anemia, nausea, seborrheic dermatitis, ataxia, peripheral neuritis, abnormal ECG

• High levels of homocysteine in the blood = heart attack

• Higher C-reactive protein (CRP) and fibrinogen

Vitamin B6

Degrades homocysteine; homocysteine requires this for metabolism

C-reactive protein (CRP) and Fibrinogen

Markers for coronary disease

• Isoniazid

• Penicillamine

• Amphetamine

• Chlorpromazine

• Oral contraceptives

Medications that lower Vit B6 levels

Vitamin B6 excess

Neurotoxicity and photosensitivity with intake of >1g dose per day

Folate

Term for Vitamin B9

Vitamin B9 (Folate)

• aka Folic acid / Pteroylglutamic acid

• Anti-anemic factor

• Functions as coenzyme in AA metabolism

Folic acid/Pteroylglutamic acid

Other term for Vit B9 (Folate)

150-300 μg/day

RDA for Vit B9 for children

400 μg/day

RDA for Vit B9 for adult men and women

• Legumes

• Fruits

• Some animal supply

• Fresh orange and fresh orange juice (important sources)

Vit B9 sources

Vitamin C

Presence of which vitamin protects folate?

400 μg folic acid

It is recommended that women of child-bearing age take daily multivitamin of _____

Vitamin B9 deficiency

• Macrocytic anemia (megaloblastic anemia) — large RBCs

• Birth defects if experienced in pregnancy:

  • Spina bifida — neural tube defects

  • Severe condition affecting spinal cord

  • Infant paralysis

• Gingival sensitivity to plaque irritation

Vitamin B9

Also required in the degradation of homocysteine

Vitamin B9 excess

• Can correct anemia (when there is Vit B12 deficiency)

  • but neurological effects persist

Cobalamin

Term for Vitamin B12

Vitamin B12 (Cobalamin)

• Most complex chemical structure

• Constituent of 2 major enzymes:

  • Methylcobalamin

  • 5-deoxyadenosylcobalamin

• Only vitamin containing the mineral cobalt, giving it a dark red color

Methylcobalamin, 5-deoxyadenosylcobalamin

Vit B12 is a constituent of these 2 major enzymes

Cyanocobalamin

Synthetic form of Vit B12

Intrinsic factor

For Vit B12 to be absorbed it has to bind with a glycoprotein _____

calcium

With the aid of _____, IF binds with Vit B12 and facilitates absorption in the small intestine

intrinsic factor

With the aid of calcium, _____ binds with Vit B12 and facilitates absorption in the small intestine

• Liver

• 1/3 in muscle, bone, skin, lungs, kidneys, spleen

Where is Vit B12 stored?

Vitamin B12

Even if adults completely stop eating animal foods, they have supplies of _____ lasting for 20-30 years

0.9-1.8 μg/day

RDA for Vit B12 for children

2.4 μg/day

RDA for Vit B12 for adult men and women

• Organ meat

• Clams

• Oysters

• Yeast

*vegetarians would need to consume sea vegetables and fortified soy milk

Vit B12 sources

Vitamin B12 deficiency

• Deficiency from diet is rare

• Strict vegetarian with no animal diet for a long period of time can suffer

• Pernicious anemia (Macrocytic/megaloblastic anemia)

  • bone marrow is unable to produce mature RBCs

  • results in large, immature RBCs

• Pallor, soreness of mouth

• Prolonged bleeding time, anorexia, dyspnea

• Weight loss, fatigue, dizziness, hypotension, disorientation

• Eventual psychosis

• Unsteadiness of gait, mental depression

• Risk for heart attack due to increased homocysteine

5-7 mins

Normal bleeding time

Pernicious anemia

A condition (Vit B12 deficiency) in which the bone marrow cannot produce mature RBCs, resulting in large, immature RBCs

Vitamin B12 deficiency

Oral manifestations:

• Bright-red tongue

• Atrophic glossitis

• Sore smooth burning tongue

Ascorbic Acid

Term for Vitamin C

Vitamin C (Ascorbic Acid)

• Chemical structure similar to glucose

• Most easily destroyed by light, heat, air, oxygen

• Potent antioxidant

• Maintain health cell function

Vitamin C

• Hold cells together

• Heal wounds, keep the immune sys intact

• Serves as electron donor for body enzymes needed for formation of collagen, serotonin, norepinephrine, bile

• Protects Vit A and E from excessive oxidation

• Quenches free radicals thought to be carcinogenic

• Facilitates Ca and nonheme iron absorption

• Synthesizes leukocytes

Vit A and E

Vitamin C protects _____ from excessive oxidation

Ca and nonheme iron

Vitamin C facilitates _____ absorption

Vitamin C

Needed in the hydroxylation of proline and lysine to hydroxyproline and hydroxylysine

Hydroxyproline and hydroxylysine

They are incorporated in the polypeptide chain in fibroblasts

• this chain combine to form a coiled helix

• secreted from the fibroblast

tropocollagen

3 helices of collagen fibers combine to form _____

collagen fibrils

Tropocollagen units combine in staggered arrangements to form _____

functional collagen

Collagen fibrils combine to form fiber that is _____

Vitamin C deficiency

• Ground substance during fiber formation (wound healing) does not decline

  • it accumulates and surrounds the fibril — preventing proper fiber synthesis

  • the scorbutic wound ends up with few collagen fibers and chaotically arranged tropocollagen fibers

ground substance

(Vitamin C deficiency) When wound begins to heal, _____ accumulates rapidly over the first few days, providing foundation for the scab

• as fiber formation begins, this begins to decline

diet

90% of Vit C is obtained from _____

Tissues with greatest metabolic activity (glands, retina, WBC)

Vit C is not stored but concentrated where?

15-75 mg/day

RDA for Vit C for children

90 mg/day

RDA for Vit C for men 19+

75 mg/day

RDA for Vit C for women 19+

• Citrus and other fruits

• Potatoes

• Dark green and deep yellow vegetables

Vit C sources

200 mg

5 servings of fruit and veggies per day provide over _____ of Vitamin C

Vitamin C

Destroyed by heat and leaches out into cooking water

Scurvy

• Classic vitamin C deficiency

• Associated with individuals who avoid fruits and vegetables

• Reported in infants who had cow’s milk formula for several months w/o Vit C supplementation

Vitamin C deficiency

• Poor, slow wound healing

• Tissue friability, decreased resistance to infection

• Fatigue, skin hemorrhage

• Joint pain, disruption of cartilage

• Failure to grow

• Soreness and swelling of joint

• Small red hemorrhages around hair follicles (perifollicular petechiae)

• Xerostomia (dry mouth)

• Hair loss

Perifollicular petechiae

Small red hemorrhages around hair follicles (Vit C deficiency)