Local anesthetic improves individuals affected with herpes simplex type 1 labialis

Chemical compositions and experimental and computational modeling activity of sea cucumber Holothuria parva ethanolic extract against herpes simplex virus type 1

Sea cucumber has antiviral activities against various viruses including herpes simplex virus type 1 (HSV-1). The purpose of the current study was to determine the chemical profile and inhibitory effects of tegument ethanolic extract of Holothuria parva on HSV-1 infection and to elucidate the mechanism of antiviral action of this marine invertebrate. Cytotoxic activity of the extract on Vero cell line was determined using the methyl thiazolyl tetrazolium (MTT) method. The different components in H. parva were determined by GC-MS analysis. To assess the antiviral activity of the extract, MTT and 50% tissue culture infective dose (TCID50) were applied. Finally, computational molecular docking was performed to screen the potential binding ability of extract contents with HSV-1 surface glycoproteins and host cell surface receptors. Using MTT assay, the non-cytotoxic concentration of the extract was measured 46.5 μg/mL. Octadecanoic acid 2-hydroxy-1-(hydroxymethyl) ethyl ester and 2',6'-acetoxylidide were two major constituents in the H. parva extract. Pre-treatment of HSV-1 with the ethanolic extract of H. parva led to a 2.1 log10 TCID50 reduction in virus titers when compared to the control group (P = 0.002). The log10 TCID50 reductions relative to the control group for co-penetration and post-penetration assays were 1.5 (P = 0.009) and 0.7 (P = 0.09), respectively. The tegument ethanolic extract of H. parva has significant antiviral properties against HSV-1. Docking analysis demonstrated that compounds of the extract [lidocaine and 2-hydroxy-1-(hydroxymethyl) ethyl ester octadecanoic acid] may cover similarly both virus and host cells binding domains leading to interference in virus attachment to cell receptors.

Herpes Labialis: A New Possibility for Topical Treatment with Well-Elucidated Drugs

Mucocutaneous infections caused by Herpes simplex virus (HSV-1 and HSV-2) are characterized by the appearance of vesicles that cause pain and embarrassment to the carrier. The standard treatment is based on the use of antivirals in gels or ointments, however, relapses are common. Local anesthetics decrease the pain caused by the lesion, in addition to showing antiviral properties. Semi-solid form facilitates application and its transformation into a thin film favors the maintenance of the formulation in place, with a more discreet final aspect. The objective of this study was to develop and evaluate formulations containing anesthetics for the treatment of cold sores. For this purpose, two semi-solid film-forming formulations were developed and evaluated, containing HPMC K100, lidocaine (LIDO) and prilocaine (PRILO) combined with adjuvants, in the presence (F1T) or not (F1) of the absorption promoter Transcutol®. The mixture of PRILO and LIDO resulted in the formation of a eutectic mixture (EM), essential for penetration of drugs into the skin. The quantification of drugs was performed by HPLC (High Performance Liquid Chromatography), and Transcutol® did not influence the release of drugs from the formulation. The bioadhesiveness of the formulation was evaluate and the drugs did not impair the adhesive potential of the polymers used. The formulations were evaluated in vivo for skin irritation and did not show any negative sign on macroscopic examination. The in vivo efficacy test proved the anesthetics' ability to decrease the lesions caused by HSV-1. Thus, the proposed formulations proved to be good alternatives to the treatment of oral lesions caused by HSV-1.