bx795 and Herpes-Simplex

Herpes simplex virus type-1 (HSV1) exploits cellular machinery for its own replicative advantage. Current treatment modalities against HSV1 cause toxicity and drug resistance issues. In the search for alternative forms of treatment, we have uncovered a small molecule, BX795, as a candidate drug with strong antiviral potential owing to its multitargeted mode of action. In this study, we show that in addition to a previously known mechanism of action, BX795 can directly interact with the proviral host factor protein kinase C (PKC) in silico. When administered to HSV1 or mock infected human corneal epithelial (HCE) cells, BX795 significantly reduces the protein level and perinuclear localization of proviral PKC-α and PKC-ζ isoforms. This activity closely mimics that of a known PKC inhibitor, Bisindolylmaleimide I (BIM I), which also inhibits viral replication. Taken together our studies demonstrate a previously unknown mechanism by which BX795 exerts its antiviral potential.

Topics: Antiviral Agents; Herpes Simplex; Herpesviridae Infections; Herpesvirus 1, Human; Humans; Protein Kinase C

To evaluate the prophylactic antiviral efficacy, corneal tolerance and toxicity of topically dosed BX795, a non-nucleoside small-molecule inhibitor of herpes simplex virus type-1 (HSV-1).. Prophylactic treatment with BX795 was performed both in-vitro on human corneal epithelial cells and in-vivo on mice prior to HSV-1 challenge. Viral burden was evaluated using a standard plaque assay. In a separate experiment, mice were treated topically 3-times daily for 4-weeks with BX795 to evaluate corneal tolerance and toxicity. Phenol-red thread measurements, fluorescein staining and optical coherence tomography (OCT) were used to evaluate tear production, dryness and corneal structural changes. Corneal sensitivity and intraocular pressure were measured using esthesiometery and tonometery respectively.. Both in-vitro and in-vivo results showed a robust suppression of HSV-1 infection when treated prophylactically with BX795. The fluorescein stain and phenol-red results for the BX795-treated eyes did not show signs of corneal surface dryness when compared to trifluridine (TFT), an FDA-approved topical antiviral. The OCT measurements showed no signs of structural changes to the cornea suggesting that BX795 treatment was well tolerated without any apparent signs of toxicity or inflammation. The corneal sensitivity of BX795-treated eyes was not significantly different from TFT-treated eyes. No significant increase in the intraocular pressure of BX795-treated mice was observed.. Prophylactic treatment with BX795 protects corneal cells from HSV-1 infection. The antiviral is well-tolerated on murine corneas without any detectable toxicity.

Topics: Animals; Cornea; Herpes Simplex; Keratitis, Herpetic; Mice; Phosphorylation; Proto-Oncogene Proteins c-akt; Pyrimidines; Thiophenes

Herpes simplex virus-1 (HSV-1) infection is known to cause skin blisters, keratitis as well as deadly cases of encephalitis in some situations. Only a few therapeutic modalities are available for this globally prevalent infection. Very recently, a small molecule BX795 was identified as an inhibitor of HSV-1 protein synthesis in an ocular model of infection. In order to demonstrate its broader antiviral benefits, this study was aimed at evaluating the antiviral efficacy, mode-of-action, and toxicity of BX795 against HSV-1 infection of three human cell lines: HeLa, HEK, and HCE. Several different assays, including cell survival analysis, imaging, plaque analysis, Immunoblotting, and qRT-PCR, were performed. In all cases, BX795 demonstrated low toxicity at therapeutic concentration and showed strong antiviral benefits. Quite interestingly, cell line-dependent differences in the mechanism of antiviral action and cytokine response to infection were seen upon BX795 treatment. Taken together, our results suggest that BX795 may exert its antiviral benefits via cell-line specific mechanisms.

Topics: Antiviral Agents; Cell Line; Cytokines; HEK293 Cells; HeLa Cells; Herpes Simplex; Herpesvirus 1, Human; Humans; Pyrimidines; Thiophenes

Herpes simplex virus type 2 (HSV-2) causes recurrent lesions in the anogenital area that may be transmitted through sexual encounters. Nucleoside analogs, such as acyclovir (ACV), are currently prescribed clinically to curb this infection. However, in some cases, reduced efficacy has been observed due to the emergence of resistance against these drugs. In our previous study, we reported the discovery of a novel anti-HSV-1 small molecule, BX795, which was originally used as an inhibitor of TANK-binding kinase 1 (TBK1). In this study, we report the antiviral efficacy of BX795 on HSV-2 infection in vaginal epithelial cells

Topics: Acyclovir; Animals; Antiviral Agents; Female; Genitalia; Herpes Genitalis; Herpes Simplex; Herpesvirus 2, Human; Mice; Pyrimidines; Thiophenes

Herpes simplex virus type 1 (HSV-1) causes recurrent mucocutaneous lesions in the eye that may advance to corneal blindness. Nucleoside analogs exemplified by acyclovir (ACV) form the primary class of antiherpetic drugs, but this class suffers limitations due to the emergence of viral resistance and other side effects. While studying the molecular basis of ocular HSV-1 infection, we observed that BX795, a commonly used inhibitor of TANK-binding kinase 1 (TBK1), strongly suppressed infection by multiple strains of HSV-1 in transformed and primary human cells, cultured human and animal corneas, and a murine model of ocular infection. Our investigations revealed that the antiviral activity of BX795 relies on targeting Akt phosphorylation in infected cells, leading to the blockage of viral protein synthesis. This small-molecule inhibitor, which was also effective against an ACV-resistant HSV-1 strain, shows promise as an alternative to existing drugs and as an effective topical therapy for ocular herpes infection. Collectively, our results obtained using multiple infection models and virus strains establish BX795 as a promising lead compound for broad-spectrum antiviral applications in humans.

Topics: Animals; Antiviral Agents; Disease Models, Animal; Enzyme Activation; Epithelium, Corneal; Eye; Herpes Simplex; Herpesvirus 1, Human; Humans; Mice, Inbred BALB C; Proto-Oncogene Proteins c-akt; Pyrimidines; Swine; Thiophenes; Virion