L12: Vitamins, Minerals and Alcohol Metabolism Flashcards
Water Soluable Vitamains?
B Complex (8)
Vitamin C
Fat Soluable Vitamins
A
D
E
K
Vitamins that Function as Co-Enzymes/ Co-Factors?
Vit A (Rhodopsin-Rod Cells)
Vit B Complex (8)
Vit K (Blood Clotting)
Vitamins that Function as Antioxidants?
Vit A
Vit C
Vit E
Vitamins that have Hormonal Functions?
Vit A (Epithelial Maintenance)
Vit D (Ca++ metabolism)
Functions of B-Complex Vitamins?
- Energy metabolism – generation of ATP from glucose and fats
- Amino acid metabolism
- Nucleotide synthesis
Enzymes that require Vitamin B1
Resulting Deficiency?
These Enzymes require Thiamin (B1)
- Pyruvate Dehydrogenase
- a-Ketogluterate Dehydrogenase
Deficiency results in Beriberi: Muscle wasting disease
What causes Beriberi?
B1 Thiamin deficiency
What is Vitamin B2 (Riboflavin) a precursor for?
NAD
What is Vitamin B3 a precursor for?
Resulting Deficiency?
B3 (Niacin) is a Pre-cursor of NAD
Pellagra: Sour Skin Dermatitis on hands and shoulder (Casal’s Collar)
What causes Pellagra?
B3 (Niacin) deficiency
Constituent of Co-A (Part of Acyetly Co-A)?
B5 (Pantothenic acid)
Co-enzyme in carboxylation/FA synthesis?
B7 (Biotin)
Role of Vitamin B9?
Resulting Deficiency?
Folic acid- B9 is essential for Neural tube formation
Spina Bifida: Neural tube deficiency
Co-enzyme key in Erythropoiesis?
B12 (Cobalamin)
What causes Spina Bifida?
Deficiency of Vitamin B9 (Folic Acid) causes impaired DNA replication in dividing cells => neural tube defects
What causes Pernicious Anemia?
Low red blood cell production resulting from lack/loss of intrinsic factor needed for the absorption of vitamin B12-Cobalmin. Intrinsic Factor deficiency caused by autoimmune disease targeting parietal cells of the stomach/ intrinsic factor)
Vitamin that is an essential cofactor in Amino Acid Metabolism?
Consequences of Deficiency?
Pyridoxal (B6) Phosphate is responsible for:
- All transamination reactions
- Some AA decarboxylation and deamination reactions
- Synthesis of neurotransmitters (GABA and serotonin)
- Heme biosynthesis
Deficiency rare - most common in alcoholics
- Anemia
- Peripheral neuropathy/ Seizures
Vitamin deficiency responsible for Anemia, Peripheral neuropathy and Seizures?
B6 Pyridoxal
Causes of B-Complex Deficiencies?
B Vit Deficiencies uncommon except in severe malnutrition and alcoholism
Are B-vitamins always good for you??
NOT protective against lung cancer, may even be harmful for men
Roles of Vitamin C?
Resulting Deficiency?
General antioxidant: scavenges free radicals preventing lipid peroxidation and DNA damage
Specific antioxidant: Many Fe and Cu-containing enzymes are dependent on ascorbic acid to maintain metals in the reduced state required for enzyme activity
- Prolyl and lysyl hydroxylases: Collagen synthesis
- Carnitine synthesis: b-oxidation of Fatty acids
- Bile acid synthesis
Deficiency results in Scurvy
How does Vitamin D Upregulate Bone Mineralization
Vitamin D undergoes Hydroxylationin liver then the Kidneys becoming Calcitriol => Calcitriol binds receptors in the intestinal mucosa which increases calcium channel expression in lumen of the intestine => Upregulates Bone Mineralization
Manifestations of Vitamin D Deficiency in Children/Adults?
Children – Rickets: inadequate bone calcification; soft cartilaginous bones
Adults – Osteomalacia: Brittle bones that break easily
