Experimental study on Reye's syndrome: inhibitory effect of interferon alfa on acetylsalicylate-induced injury to rat liver mitochondria.

Viral infection and acetylsalicylate (ASA)-induced mitochondrial aberration have been reported to play important roles in the pathogenesis of Reye's syndrome. We report that increasing amounts of ASA (0 to 250 mumol/L) resulted in increases in state 4 respiration and decreases in state 3 respiration in rat liver mitochondria in vitro when using alpha-ketoglutarate and/or beta-hydroxybutyrate as respiratory substrates, but not when using succinate as substrate. Interferon alfa (IFN-alpha) (1.5 to 5 x 10(4)IU/mL, approximately 1/100 the therapeutic dosage for humans) and interleukin-1 (IL-1) (1.5 to 2 x 10(4)IU/mL, nearly equivalent to the therapeutic dosage) decreased the severity of the above effects via interaction with mitochondrial membranes. Interferon gamma (IFN-gamma) and interleukin-2 (IL-2) had no such protective effect. Electron microscopic observation indicated that IFN-alpha prevented the induction of mitochondrial swelling by ASA. These results suggest that IFN-alpha may prove to be effective for the treatment of Reye's syndrome.