Vitamin E supplementation in cystic fibrosis

Area of Science:

• Biochemistry
• Pediatrics
• Nutritional Science

Background:

• Vitamin E, a lipid-soluble antioxidant, protects lung tissue from oxidative damage, a key factor in cystic fibrosis (CF) pathogenesis.
• Plasma/serum vitamin E levels in CF patients may not accurately reflect tissue concentrations due to lipoprotein variations.
• Erythrocyte vitamin E concentration is a potential biomarker for tissue vitamin E status, previously unstudied in pediatric CF.

Purpose of the Study:

• To investigate erythrocyte vitamin E concentrations in children with cystic fibrosis.
• To determine the efficacy of two different daily vitamin E supplementation doses (15 mg vs. 100 mg) on erythrocyte vitamin E levels.
• To establish the optimal vitamin E supplementation regimen for normalizing tissue vitamin E levels in CF.

Main Methods:

• Erythrocyte vitamin E concentrations were measured using high-performance liquid chromatography.
• Measurements were taken before and one year after initiating vitamin E supplementation in pediatric CF patients.
• Patients received either 15 mg or 100 mg of vitamin E daily.

Main Results:

• Nearly all unsupplemented CF patients exhibited erythrocyte vitamin E levels below the normal range.
• Supplementation with 100 mg/day of vitamin E normalized erythrocyte vitamin E concentrations in most children.
• A 15 mg/day dose of vitamin E did not significantly improve erythrocyte vitamin E levels.
• Observed improvements were independent of changes in general dietary intake.

Conclusions:

• Tissue vitamin E levels are suboptimal in children with cystic fibrosis not receiving supplementation.
• A daily intake of 100 mg of vitamin E is effective in normalizing erythrocyte vitamin E levels in most pediatric CF patients.
• Current vitamin E supplementation guidelines for CF may require adjustment to ensure adequate tissue levels.