Vitamin B5 - Pantothenic Acid Flashcards
List dietary sources of pantothenic acid
Found in virtually all plant and animal products Particularly good sources: - meats, especially liver - egg yolks - legumes - whole grains - potatoes, mushrooms, broccoli, avocado - royal jelly
Describe the digestion of pantothenic acid
Found in food as:
Free pantothenic acid
Or bound as part of coenzyme A
- CoA is hydrolyzed to free pantothenic acid in the intestines to be absorbed
Describe the absorption of pantothenic acid
Absorbed principally in the jejunum
Two mechanisms
- Sodium dependent active multivitamin transporter
- Passive diffusion
Describe the transport of pantothenic acid
Transported in free form in blood
Higher levels are found within the red blood cells compared to within the plasma/serum
Describe the function and mechanism of action of pantothenic acid
As part of CoA molecule
- energy-nutrient metabolism
- synthesis of lipids: cholesterol, bile salts, FAs, steroid hormones, phospholipids, sphingomyelins
Formation of heme group in hemoglobin
Acetylation of proteins, sugars and drugs
Can accelerate healing
- post operatively, in the IV form, can accelerate cell multiplication
Describe the metabolism and excretion pantothenic acid
Excreted intact in urine primarily
Small amount excreted in feces
Describe consequences and symptoms of deficiency of pantothenic acid
Wildly distributed deficiency is rare and is usually combined with other deficiencies
“Burning feet syndrome”
- numbness of toes and sensation of burning in the feet
- aggravated by heat & ameliorated by cold
- fatigue and weakness
- vomiting
- restlessness, depression and irritability
Glossitis or cheilosis/stomatitis not responding to other B vitamin supplementation
Who is at increased risk of deficiency of pantothenic acid?
Adolescents
Alcoholics
Diabetics
Describe consequences and symptoms of toxicity of pantothenic acid
None reported with doses of 10mg/d for 6 months
Doses of >100mg/d may increase excretion of niacin
Describe the assessment of nutrient status of pantothenic acid
Urinary pantothenate excretion (most reliable)
Blood concentrations
Clinical response to supplementation
Discuss some of the therapeutic uses (clinical indications) of pantothenic acid
Prevention of adrenal dysfunction as part of the adrenal support program (not on its own)
Hyperlipidemia (pentethine)