Imbalance in corneal redox state during herpes simplex virus 1-induced keratitis in rabbits. Effectiveness of exogenous glutathione supply

A significant decrease in the antioxidant glutathione (GSH) was found in th e corneal tissue of rabbits with Herpes Simplex 1 (HSV-1)-induced keratitis . Such a decrease was due to a loss of the reduced species, since no increa se in its oxidized form was observed. Topical administration of purified GS H was able to reduce the virus titre in corneal tissue and, at the same tim e, was effective in reducing the severity and progression of keratitis and conjunctivitis. This effect was paralleled by a partial recovery in the cor neal GSH content. In vitro experiments performed on HSV-1 infected corneal- derived rabbit cells showed that exogenous GSH reduced virus titre in the s upernatant of infected cells. These results are in agreement with our previ ous findings that an oxidative environment, due to GSH depletion, is necess ary for virus replication and suggest that topical GSH treatment could be c onsidered as complementary therapy in HSV-1-induced keratitis, (C) 2000 Aca demic Press.