Antiviral Activity of Diterpenes From Canistrocarpus Cervicornis against Human Herpesvirus 1 and Bovine Herpesvirus 5

Human alphaherpesvirus 1 is an etiologic agent of infection endemic in the world transmitted by oral to oral oral-genital contact, from mothers causing neonatal herpes and complications such encephalitis or ocular disease. Bovine alphaherpesvirus 5 is an important agent of meningoencephalitis in cattle and has been identified in outbreaks of neurological disease in bovine in several Brazilian States. The aims of this work were to evaluate cytotoxic effect, antiviral properties of the diterpenes 1 and 2 isolated from Canistrocarpus cervicornis. The results of cytotoxic effects in VERO cell showed diterpene 1 more cytotoxic in MTT and Neutral red assay than diterpene 2. The low value to effective concentration required to diterpenes achieve 50% protection to Vero cell showed to diterpene 1 high selectivity index. Both compounds were not cytotoxic to MDBK cell, but they are not able to inhibit Bovine alphaherpesvirus 5 (BoHV-5RJ42/01) replication. Diterpenes 1 and 2 interacted directly with Human alphaherpesvirus 1 (KOS) and BoHV-5RJ42/01 reducing their infectivity on VERO and MDBK cells but they did not inhibit KOS and BoHV- 5RJ42/01 attachment and penetration in Vero and MDBK cells respectively.

Keywords: Canistrocarpus cervicornis; Diterpenes; Human alphaherpesvirus 1; KOS, Bovine alphaherpesvirus 5 BoHV-5; Antiviral