Comparative study of the effect of 21-aminosteroid and alpha-tocopherol on models of acute oxidative renal injury.

Abstract

21-Aminosteroids have incited a great deal of interest owing to its ability to inhibit lipid peroxidation and prevent organ damage. The main mechanism by which 21-aminosteroids inhibit lipid peroxidation is similar to the naturally occurring chain-breaking antioxidant alpha-tocopherols. Therefore, to determine whether 21-aminosteroids offer any advantage over alpha-tocopherol, we compared their effects on an in vivo and in vitro models of renal injury. 21-Aminosteroid (U-74006 F) at 3 mg/kg or alpha-tocopherol succinate at 10 mg/kg was administered intravenously once before bilateral renal ischemia and again before reperfusion. Acute administration 21-aminosteroid but not alpha-tocopherol, was attended by suppression of ischemia reperfusion-induced renal lipid peroxidation and injury. However, 4 weeks of dietary enrichment of rats with alpha-tocopherol (1000 IU/kg) was effective in suppressing these ischemia reperfusion-induced changes. In cell culture system, concurrent presence of 21-aminosteroid but not alpha-tocopherol abrogated H2O2-induced renal epithelial lipid peroxidation and injury. However, alpha-tocopherol was completely effective when cells were incubated with it for 14 h. Further, only the cells incubated with vitamin E for 14 h-but not for 1 or 3 h-had a significant increase in vitamin E content, which suggests that a delay in prompt cellular up take of vitamin E may explain its lack of acute effects. Thus, unlike alpha-tocopherol, 21-aminosteroid appears readily and completely available for its chain-breaking antioxidant activity both in vitro and in vivo. 21-Aminosteroids may, therefore, offer a therapeutic advantage over alpha-tocopherols in acute injury settings.

• Authors: A K Salahudeen, C Wang, V K Kanji
• Journal: Free radical biology & medicine (Free Radic Biol Med) Vol. 21 Issue 5 Pg. 691-7 ( 1996) ISSN: 0891-5849 [Print] United States
• PMID: 8891671 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antioxidants
• Free Radical Scavengers
• Pregnatrienes
• Vitamin E
• Hydrogen Peroxide
• tirilazad

Topics

• Animals
• Antioxidants (pharmacology)
• Disease Models, Animal
• Free Radical Scavengers (pharmacology)
• Hydrogen Peroxide (toxicity)
• Kidney (drug effects, injuries, metabolism)
• LLC-PK1 Cells
• Lipid Peroxidation (drug effects)
• Male
• Pregnatrienes (pharmacology)
• Rats
• Rats, Sprague-Dawley
• Reperfusion Injury (metabolism, prevention & control)
• Swine
• Vitamin E (pharmacokinetics, pharmacology)