Vitamins

Vitamin B6

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Vitamin B6, Pyridoxine, Pyridoxal, Pyridoxamine, Pyridoxal Phosphate, PyrP

  • See Also
  • Physiology
  1. Vitamin B6 refers to a group of picolines, water-soluble B Vitamins: Pyridoxine, Pyridoxal, and Pyridoxamine
  2. Vitamin B6 is converted to Pyridoxal Phosphate (PyrP)
  3. Pyridoxal Phosphate is an important coenzyme, a Cofactor for more than 100 enzymes (esp. Amino Acid synthesis)
    1. Amino Acid synthesis (including all transamination, in which it is a Cofactor for all transaminases)
      1. Alanine (and 2-ketoglutarate) are synthesized from pyruvate and glutamate via PyrP assisted enzyme
      2. Glutamate (and oxaloacetate) are synthesized from 2-ketoglutarate and Aspartate via PyrP assisted enzyme
      3. Histamine is sythesized from Histamine via PyrP assisted enzyme
      4. Cystathionine is sythesized from Homocysteine and serine via PyrP assisted enzyme
    2. Neurotransmitter synthesis (e.g. Serotonin, Norepinephrine, GABA)
      1. GABA (gamma-aminobutyric acid) is synthesized from Glutamate
      2. Dopamine is synthesized from Levodopa
    3. Sphinglipid synthesis
    4. Glycogen synthesis
    5. Aminolevulinic Acid
  4. Metabolism
    1. Vitamin B6 degrades to pyridoxic acid which is renally excreted
  • Preparations
  • Food Sources
  1. Meat
  2. Poultry
  3. Fish
  4. Bananas
  5. Bran
  6. Nuts
  7. Whole-grain bread
  8. Cereals
  9. Soybeans
  10. Vegetables
  • Causes
  • Vitamin B6 Deficiency
  1. Medication Causes of Vitamin B6 Deficiency
    1. Isoniazid (INH)
    2. Levodopa
  2. Signs of Vitamin B6 Deficiency
    1. Glossitis
    2. Peripheral Neuropathy
    3. Dementia
    4. Niacin Deficiency
      1. Pyridoxine facilitates tryptophan conversion to Niacin
      2. Pyridoxine deficiency may result in Niacin Deficiency
  • Efficacy
  • Potential benefit of Vitamin B6
  1. Effective in Hyperemesis
    1. Vutyavanich (1995) Am J Obstet Gynecol 173(3 Pt 1):881-4 +PMID: 7573262 [PubMed]
  2. May lower Coronary Artery Disease risk
    1. Based on retrospective studies
    2. Higher Vitamin B6 intake associated with lower Homocysteine
    3. Rimm (1998) JAMA 279:359 [PubMed]
  • Resources
  1. Vitamin B6 (Harvard School of Public Health)
    1. https://www.hsph.harvard.edu/nutritionsource/vitamin-b6/
  2. Vitamin B6 (Wikipedia)
    1. https://en.wikipedia.org/wiki/Vitamin_B6