title: Enrichment of rat hepatic organelles by vitamin E administered subcutaneously.
abstract: Novel modes of administering antioxidants to improve delivery to targeted tissues or cells may be advantageous in preventing oxidant-induced pathologies. Vitamin E (alpha-tocopherol) has been shown to be protective in several models of liver injury. The objectives of this study were: (1) to determine if subcutaneously (s.q.) administered emulsified vitamin E enriched liver and hepatic subcellular fractions with the antioxidant and (2) to carry out a time-dependent analysis of serum and tissue vitamin E in rats receiving daily s.q. vitamin E. In the first experiment rats injected daily s.q. with emulsified vitamin E for 9 d increased serum, total liver, liver mitochondria, and liver microsomes by 8-, 16-, 30-, and 29-fold, respectively, compared with placebo injections. Similar enrichment was observed after intramuscular injections. In the second experiment, daily doses of s.q. vitamin E increased liver concentrations 40-fold by 9 d, which decreased to 22-fold by 18 d, whereas serum adjusted vitamin E levels maximized with a 24-fold increase by day 3 and plateaued thereafter. In conclusion, s.q. administration of emulsified vitamin E to rats resulted in substantially elevated serum and liver concentrations of alpha-tocopherol compared with levels achievable by dietary supplementation. The s.q. route of administration is a potentially effective parenteral mode of delivery of vitamin E for conditions in which hepatic oxidative stress is present.
authors.affiliation: Pediatric Liver Center, University of Colorado Health Sciences Center and The Children's Hospital, Denver, CO 80218, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Gumpricht
authors.forename: Michael W
authors.initials: MW
authors.lastname: Devereaux
authors.forename: Maret
authors.initials: M
authors.lastname: Traber
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Sokol
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D004655:Emulsions / Q000008:administration & dosage / Q000493:pharmacokinetics; D007279:Injections, Subcutaneous; D008099:Liver / Q000378:metabolism; D008862:Microsomes, Liver / Q000737:chemistry / Q000378:metabolism*; D008930:Mitochondria, Liver / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D014810:Vitamin E / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D024502:alpha-Tocopherol / Q000032:analysis
chemical_list: D000975:Antioxidants; D004655:Emulsions; D014810:Vitamin E; D024502:alpha-Tocopherol