Alpha-tocopheryl succinate protects hepatocytes from chemical-induced toxicity under physiological calcium conditions.

Published

Journal Article

Rat and canine hepatocyte suspensions were exposed to toxic concentrations of ethyl methanesulfonate (EMS) and ionophore A-23187 in the presence and absence of extracellular calcium (Ca2+) and alpha-tocopheryl succinate (alpha-TS). The exogenous administration of alpha-TS (25 microM) completely protected hepatocytes from chemically-induced toxicity when exposed to 'physiological' free extracellular calcium concentrations (0.8-1.5 mM). Under these protective conditions the cellular accumulation of both alpha-TS (2.8 nmol/10(6) cells) and alpha-T (0.91 nmol/10(6) cells) were observed. Hepatocytes exposed to unesterified alpha-tocopherol (alpha-T, 25 microM) or alpha-tocopheryl acetate (alpha-TA, 25 microM), however, were not protected from the toxic effect of chemicals even though these treatments resulted in the marked accumulation of cellular alpha-T (2.65 nmol/10(6) cells) and alpha-TA (2.3 nmol/10(6) cells), respectively. Our findings suggest that the supplementation of endogenous stores of alpha-T or alpha-TA does not promote protection against chemical toxicity and that alpha-TS cytoprotection results not from the accumulation of alpha-T but rather from the cellular presence of the intact alpha-TS molecule. Thus alpha-TS appears to possess cytoprotective properties that differ from other vitamin E congeners.

Full Text

Duke Authors

Cited Authors

  • Fariss, MW; Merson, MH; O'Hara, TM

Published Date

  • April 1989

Published In

Volume / Issue

  • 47 / 1

Start / End Page

  • 61 - 75

PubMed ID

  • 2496490

Pubmed Central ID

  • 2496490

International Standard Serial Number (ISSN)

  • 0378-4274

Digital Object Identifier (DOI)

  • 10.1016/0378-4274(89)90086-6

Language

  • eng

Conference Location

  • Netherlands