Pentostatin antagonizes the antiviral activity of MBX-2168 by inhibiting the biosynthesis of the active compound

Autor: Terry L. Bowlin, Natalie R. Hagen, Brian G. Gentry, Marie L. Nguyen, John D. Williams
Rok vydání: 2020
Předmět:
Zdroj: Antiviral Res
ISSN: 1872-9096
Popis: MBX-2168 has a mechanism of action similar to that of acyclovir (ACV) and ganciclovir (GCV), but two unique steps differentiate this drug from ACV/GCV. First, MBX-2168 is, at least partially, phosphorylated by the endogenous cellular kinase TAOK3 to a monophosphate. The second involves the removal of a moiety at the 6-position of MBX-2168-MP by adenosine deaminase like protein-1 (ADAL-1). It has been previously demonstrated that co-incubation with pentostatin (dCF), an ADAL-1 inhibitor, antagonizes the anti-viral activity of MBX-2168. We therefore hypothesize that inhibiting ADAL-1 results in a reduction of active compound produced in virus-infected cells. To test this, we examined the effect dCF has on the conversion of MBX-2168 to a triphosphate in HSV-1 and HCMV-infected cells. Our results demonstrate incubation of MBX-2168 alone or with dCF in HCMV-infected cells resulted in 53.1±0.7 and 39.4±1.5 pmol triphosphate/10(6) cells at 120 hours, respectively. Incubation of MBX-2168 alone or with dCF in Vero cells resulted in 12.8±0.1 and 6.7±0.7 pmol triphosphate/10(6) cells at 24 hours, respectively. HSV-1-infected Vero cells demonstrated no statistical difference in triphosphate accumulation at 24 hours (13.1±0.3 pmol triphosphate/10(6) cells). As expected, incubation with dCF resulted in the accumulation of MBX-2168-MP in both HFF (9.8±0.9 pmol MBX-2168-MP/10(6) cells at 120 hours) and Vero cells (4.7±0.3 pmol MBX-2168-MP/10(6) cells at 24 hours) while no detectable levels of monophosphate were observed in cultures not incubated with dCF. We conclude that dCF antagonizes the anti-viral effect of MBX-2168 by inhibiting the production of triphosphate, the active compound.
Databáze: OpenAIRE