Introduction. Herpes simplex virus 1 (HSV-1) is a neurotropic virus that after primary infection of epithelial cells becomes latent in neurons of the peripheral nervous system and can be periodically reactivated resulting in recurrent clinical or subclinical episodes throughout life. It induces several diseases (i.e. herpes labialis, herpes simplex encephalitis), and experimental studies also suggest a causal link between recurrent HSV-1 infection and neurodegenerative disorders. HSV-1 infections are treated with antiviral agents, such as acyclovir, but immunocompromised patients could need long-term anti-herpetic therapy, inducing drug resistance. Thus, the development of novel anti-HSV-1 treatments is needed. Resveratrol is a natural polyphenolic compound with a range of pharmacological properties, including antiviral activity, but its pharmacokinetic consists of rapid metabolism and poor bioavailability. The synthesis of resveratrol derivatives, in which some functional groups are modified, aims to find molecules with the same or better properties than resveratrol, but with higher bioavailability. Here we investigated the anti-HSV-1 properties of GT-2.9 [(E)-1,1'-(but-2-ene-1,4-diylbis(4-hydroxy-3,1-phenylene)) bis(ethan-1-one)], a synthetic resveratrol derivative. Materials and Methods. Confluent monolayers of African green monkey (Vero), human embryonic kidney (HEK), neuroblastoma (SH-SY5Y) and glioblastoma (A172) cells, primary murine neurons/astrocytes were infected with HSV-1 (multiplicity of infection of 1) for 24 hrs. Infected cells were subjected to time-of-addition assay with GT-2.9 (40 µg/ml). Viral titers were quantified by standard assays. Viral and cellular protein expression was examined by q-RT-PCR, western blotting and confocal microscope analysis. Results. Our results demonstrated that GT-2.9 treatment was not cytotoxic (CC50=71 µg/ml), and the molecule showed great antiviral properties against HSV-1 (IC50=2.98 µg/ml; SI=24). GT-2.9 was able to inhibit the post-adsorption phase of HSV-1 life-cycle (more than 2 log inhibition respect to GT-2.9-not treated) by interfering with the immediate-early viral protein production, that are needed for the expression of early and late viral gene products. The antiviral effect of GT-2.9 was associated to the inhibition of the NF-?B signaling pathway and the activation of the transcription factor Nrf2. In addition, when the molecule was added in combination with acyclovir, a synergistic action against HSV-1 infection was observed. Conclusions. Our in vitro data suggest GT-2.9 as a promising resveratrol derivative with anti-HSV-1 activity. In addition, it could be considered for combinatorial drug treatment with nucleoside analogues, such as acyclovir.
GT-2.9, a synthetic resveratrol derivative, inhibits herpes simplex virus type 1 (HSV-1) life-cycle in different in vitro HSV-1 infection models
2020
Abstract
Introduction. Herpes simplex virus 1 (HSV-1) is a neurotropic virus that after primary infection of epithelial cells becomes latent in neurons of the peripheral nervous system and can be periodically reactivated resulting in recurrent clinical or subclinical episodes throughout life. It induces several diseases (i.e. herpes labialis, herpes simplex encephalitis), and experimental studies also suggest a causal link between recurrent HSV-1 infection and neurodegenerative disorders. HSV-1 infections are treated with antiviral agents, such as acyclovir, but immunocompromised patients could need long-term anti-herpetic therapy, inducing drug resistance. Thus, the development of novel anti-HSV-1 treatments is needed. Resveratrol is a natural polyphenolic compound with a range of pharmacological properties, including antiviral activity, but its pharmacokinetic consists of rapid metabolism and poor bioavailability. The synthesis of resveratrol derivatives, in which some functional groups are modified, aims to find molecules with the same or better properties than resveratrol, but with higher bioavailability. Here we investigated the anti-HSV-1 properties of GT-2.9 [(E)-1,1'-(but-2-ene-1,4-diylbis(4-hydroxy-3,1-phenylene)) bis(ethan-1-one)], a synthetic resveratrol derivative. Materials and Methods. Confluent monolayers of African green monkey (Vero), human embryonic kidney (HEK), neuroblastoma (SH-SY5Y) and glioblastoma (A172) cells, primary murine neurons/astrocytes were infected with HSV-1 (multiplicity of infection of 1) for 24 hrs. Infected cells were subjected to time-of-addition assay with GT-2.9 (40 µg/ml). Viral titers were quantified by standard assays. Viral and cellular protein expression was examined by q-RT-PCR, western blotting and confocal microscope analysis. Results. Our results demonstrated that GT-2.9 treatment was not cytotoxic (CC50=71 µg/ml), and the molecule showed great antiviral properties against HSV-1 (IC50=2.98 µg/ml; SI=24). GT-2.9 was able to inhibit the post-adsorption phase of HSV-1 life-cycle (more than 2 log inhibition respect to GT-2.9-not treated) by interfering with the immediate-early viral protein production, that are needed for the expression of early and late viral gene products. The antiviral effect of GT-2.9 was associated to the inhibition of the NF-?B signaling pathway and the activation of the transcription factor Nrf2. In addition, when the molecule was added in combination with acyclovir, a synergistic action against HSV-1 infection was observed. Conclusions. Our in vitro data suggest GT-2.9 as a promising resveratrol derivative with anti-HSV-1 activity. In addition, it could be considered for combinatorial drug treatment with nucleoside analogues, such as acyclovir.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
