Vitamin E and vitamin E acetate absorption from self-assembly systems under pancreas insufficiency conditions

Chimia (Aarau). 2014;68(3):129-34. doi: 10.2533/chimia.2014.129.

Abstract

We determined the bioavailability of vitamin E from self-assembly structures in patients with diagnosed chronic pancreas insufficiency. Vitamin E solubilized in dispersed inverted bicontinuous cubic phase and in micellar formulation was delivered directly to the small intestine by tube-feeding. A cross-over study with randomization of 6 subjects and 2 treatments including a combined dose of 18 mg (27 IU) of vitamin E (RRR-[5,7-methyl-((2)H6)]-α-tocopherol) and 27 mg (27 IU) vitamin E acetate (RRR-[5-methyl-(2)H3]-α-tocopheryl acetate) was applied over a time period of 1 h. Plasma samples were collected for 56 h and analyzed by liquid chromatography-mass spectrometry. Appearance of labeled tocopherols originating from the treatment started at 25 h and reached Cmax (0.6-4.6 μM depending on subject) in the 7-9 h window. From the Tmax onwards, both forms of tocopherols diminished slowly to 30-50% of their maxima within 56 h. Strong inter-individual variation was observed in the plasma appearance curves (relative standard deviation varied between 38-45%). No significant discrimination was found between the absorption of free or acetylated forms of deuterated α-tocopherol confirming that application of acetylated α-tocopherol provides the same bioavailability as free α-tocopherol. This observation is valid in both dispersed inverted bicontinuous cubic phase and micellar formulations. Furthermore, since the area-under-the-curve values from cubic phase and from micellar formulations are similar, the cubic phase formulation could represent an alternative delivery system for lipophilic micronutrients in conditions or studies where polysorbate-based micelles cannot be generated.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antioxidants / administration & dosage*
  • Antioxidants / pharmacokinetics*
  • Antioxidants / therapeutic use
  • Biological Availability
  • Cross-Over Studies
  • Drug Delivery Systems*
  • Enteral Nutrition
  • Exocrine Pancreatic Insufficiency / blood
  • Exocrine Pancreatic Insufficiency / drug therapy*
  • Humans
  • Intestinal Absorption
  • Male
  • Middle Aged
  • Vitamin E / administration & dosage*
  • Vitamin E / blood*
  • Vitamin E / therapeutic use
  • Young Adult
  • alpha-Tocopherol / administration & dosage
  • alpha-Tocopherol / blood
  • alpha-Tocopherol / therapeutic use

Substances

  • Antioxidants
  • Vitamin E
  • alpha-Tocopherol