RESUMO
Prostaglandin Al (PGA1) inhibits Mayaro virus replication in Aedes albopictus cells at nontoxic doses to uninfected cells . At 10 ug/ml, PGA1 decreases virus production by 90 (per cent). The presence of PGA1 during virus adsorption, with no treatment after infection, reduces virus yield by 41 (per cent). Antiviral activity is observed even when treatment starts at one or two hours post-infection. However, in cells pre-treated with PGA1 during 24 hours, virus replication is not impaired. Thus, events ocurring during initial stages of infection and after virus adsorption and penetration must be the target of PGA1 action. SDS-PAGE analysis of 35S-methionine labelled proteins shows that PGA1 inhibits the synthesis of viral proteins and induces the synthesis of polypeptides with molecular weight of 70 kDa, 57 kDa and 23 kDa. In cells pre-treated with actinomycin D the induction of those proteins is suppressed. In addition, actinomycin D treatment prevents PGA1 antiviral activity, indicating that PGA1-induced stress proteins are probably involved in this mechanism