Vitamins

Question 1

Fat soluble vitamins

Answer 1

• Absorption depends on normal fat digestion & absorption
• Stored in Liver
• Vitamin A (Retinol, B-Carotens)
• Vitamin D (Cholecalciferol)
• Vitamin K (Phylloquinones, Menaquinones)
• Vitamin E (Tochopherols)

Question 2

Water soluble vitamins

Answer 2

• Daily supplements
• Not stored (except B12)
• Easily absorbed - don’t require Chylomicrons
• Vitamin C (Absorbic Acid)
• Vitamin B (Thiamine-B1, Riboflavin-B2, Niacin-B3, Panthothenic Acid-B5, Pyridoxine-B6, Biotin-B7, Folic Acid-B9, Cobalamin-B12)

Question 3

Vitamin C, Absorbic Acid

Answer 3

• Water soluble
• Functions: CT/Collagen synthesis & wound healing
• Microcytic Anemia: Low dietary Vit C, reduced iron absorption (ferrous state)
• Antioxidant - reduce chronic disease
• Deficiency: Scurvy - CT defects, perifollicular hemorrhage, sore bleeding gums, loose teeth, bruising, delayed wound healing

Question 4

Thiamine, Vit B1

Answer 4

• Water soluble
• Coenzyme: TPP (Thiamine Pyrophosphate)
• Reactions: Oxidative Decarboxylation of alpha-keto acids, Transketolase in PPP
• Deficiency: Beriberi, Wernicke-Korsakoss Syndrome

Question 5

Riboflavin, Vit B2

Answer 5

• Water soluble
• Coenzyme forms: Flavin Mononucleotide (FMN) & Flavin Adenine Dinucleotide (FAD)
• Reactions: Oxidation reduction of TCA, B-Oxidation
• Deficiency: Nutritional
• Symptoms: Cheiolsis, glossitis, facial dermatitis

Question 6

Vit B3, Niacin

Answer 6

• Coenzyme forms: NAD+, NADPH
• Reactions: Oxidation reduction, HMP Shunt, FA/Cholesterol synthesis
• Therapeutic uses: Hyperlipoproteinemia Type IIB - inhibits AT lipolysis & reduces FFAs
• Risk factors: Corn based diet (Tryptophan & Niacin deficient), Harnut Disease, Carcinoid Syndrome (excessive Trp —> Serotonin)

Question 7

Pyridoxine, Vit B6

Answer 7

• Transamination of AAs - Aminotransferases (AST & ALT)
• AA Decarboxylation (Neurotransmitter synthesis)
• Condensation - ALA Synthase (Heme synthesis)
• Homocysteine metabolism - Cystathionine synthase
• Risk factors: Isoniazid therapy (anti-TB)
• Treatment: Pyridoxine supplements with INH
• Deficiency clinical features: Peripheral neuropathy, microcytic anemia, CV dx risk, seizures