Several clinical studies have shown that cyclosporin A (CsA) is effective f
or treating a variety of chronic inflammatory and autoimmune diseases. Beca
use reactive oxygen species are believed to play a key role in the developm
ent of these diseases, causing cell apoptosis, we investigated whether CsA
inhibits H2O2-induced apoptosis. Preincubation of human fibroblasts with Cs
A dose-dependently decreased H2O2-induced apoptosis. Apoptosis suppression
by CsA was correlated with the prevention of mitochondrial dysfunction and
caspase activation. Thus, our results suggest that the inhibition of apopto
sis by CsA may at least partly contribute to the anti-inflammatory effect o
f CsA. (C) 1999 Federation of European Biochemical Societies.