Vitamin B6 (pyridoxine)

Question 1

What are the forms of Vit B6?

Answer 1

Pyridoxine (PN), pyridoxal (PL), pyridoxamine (PM). All 3 forms can be converted to active coenzymes pyridoxal phosphate (PLP) and pyridoxamine phosphate (PMP). NB: Plant foods contain the more stable PN while animal products contain PL and PM.

Question 2

Where in the GI is vit B6 absorbed?

Answer 2

It (all 3 forms) is absorbed passively in the jejunum and rates are 71% to 82%.

Question 3

How is vit B6 transported in the plasma?

Answer 3

~60% of vit B6 is transported in the plasma in the form PLP bound to albumin and hemoglobin in the erythrocyte.

Question 4

What is the role of vit B6?

Answer 4

Since vit B6 is involved in over 100 enzymatic rxt, they play a role in:

1. pro, a.a., lipid metabolism.
2. gluconeogenesis.
3. heme synthesis and immune function
4. neurotransmitter synthesis
5. steroid receptor binding
6. CNS development

Question 5

What are good sources of Vit B6?

Answer 5

Fortified cereals, organ meats, whole grains, chicken, turkey, salmon, milk, cheese, carrots, brown rice, spinach, sunflower seeds.

Question 6

What results form Vit B6 deficiency?

Answer 6

1. Microcytic anemia
2. seborrheic dermatitis
3. confusion and depression

Question 7

Who is at greatest risk for Vit B6 deficiency?

Answer 7

Alcoholics, the elderly, people on medication therapy that inhibit vitamin activity (i.e corticosteroids, or anticonvulsants).