[Show abstract][Hide abstract] ABSTRACT: Oxyresveratrol, a major compound purified from Artocarpus lakoocha, a Thai traditional medicinal plant, was evaluated for its mechanism of action and therapeutic efficacy on cutaneous herpes simplex virus (HSV) infection in mice. The inhibitory concentrations for 50% HSV-1 plaque formation of oxyresveratrol, three clinical isolates, thymidine kinase (TK)-deficient and phosphonoacetic acid (PAA)-resistant HSV-1 were 19.8, 23.3, 23.5, 24.8, 25.5 and 21.7 μg/ml, respectively. Oxyresveratrol exhibited the inhibitory activity at the early and late phase of viral replication and inhibited the viral replication with pretreatment in one-step growth assay of HSV-1 and HSV-2. Oxyresveratrol inhibited late protein synthesis at 30 μg/ml. The combination of oxyresveratrol and acyclovir (ACV) produced synergistic anti-HSV-1 effect, as characterized by the isobologram of plaque inhibition. Mice orally treated with oxyresveratrol (500 mg/kg/dose) dose at 8 h before and three times daily had significant delay in herpetic skin lesion development (P < 0.05). Topical application of 30% oxyresveratrol ointment five times daily significantly delayed the development of skin lesions and protected mice from death (P < 0.0001).
No preview · Article · Oct 2008 · Antiviral Research
[Show abstract][Hide abstract] ABSTRACT: Herpes simplex virus (HSV)-2 caused a genital ulcer in a 40-year-old allogenic stem cell recipient, and a secondary herpetic whitlow appeared during 2 months of acyclovir (ACV) therapy. Both genital ulcer, and whitlow were cured 3 months later, but 6 months after recovery the whitlow alone recurred. DNA of the genital, first, and recurrent whitlow isolates showed similar endonuclease digestion fragment profiles. The genital virus was ACV-sensitive, and the two whitlow isolates were ACV-resistant/thymidine kinase (TK)-deficient. The TK gene of the whitlow isolates had the same frame shift from the 274th amino acid and termination at the 347th amino acid due to the deletion of a cytosine at the 819th nucleotide. Because the temperature of the thumb is 33/34 degrees C or lower, the temperature sensitivity of the isolates were compared, and both whitlow isolates were significantly more temperature-sensitive (ts) at 39 degrees C than the genital isolate. The two whitlow isolates showed cutaneous pathogenicity in mouse ear pinna but not midflank, while the genital isolate was pathogenic at both sites, suggesting that temperature adaptation was an important element of pathogenicity in the whitlow. The virus populations of isolates of the genital, and first whitlow were examined by 31, and 82 clones, respectively, and the clones from genital, and whitlow isolates were ACV-sensitive, and -resistant, respectively, showing their homogeneity. The acyclovir-sensitive genital lesion had spread as a TK-deficient/ts herpetic whitlow during ACV treatment, and an apparently TK-deficient virus adapted to the local temperature might have caused the whitlow recurrence.
No preview · Article · Nov 2007 · Journal of Medical Virology
[Show abstract][Hide abstract] ABSTRACT: Hepatitis is caused by hepatitis viruses, but hepatitis or hepatocellular enzyme abnormalities is sometimes associated with infection by the hepatiticomimetic viruses. The direct and indirect effects of infection with hepatiticomimetic viruses were examined in two human hepatocyte systems. Poliovirus, adenovirus, and herpes simplex virus (HSV) induced cytopathology in Hep G2 cells. Measles virus caused no change in hepatocytes. Poliovirus infection did not affect cellular protein synthesis, and the peak of hepatocellular enzyme release coincided with the peak of virus release. The increase in adenovirus protein synthesis correlated with the decrease of transferrin synthesis, and enzyme release was not prominent. HSV induced viral protein synthesis with enhanced processing and inhibition of synthesis of alpha1-antitrypsin. The peak of enzyme release was later than the peak of virus release. In primary hepatocytes, poliovirus, adenovirus, and induced extensive cytopathology and enzyme release, and VZV caused cytopathology and significant but minute enzyme release. The ratio of lactate dehydrogenase to aspartate aminotransferase release was larger in poliovirus infection in both hepatocytes than in HSV or VZV infection. Although poliovirus and adenovirus are released by cytolysis and HSV and VZV are secreted by exocytosis of cytoplasmic vacuoles, enzyme release was independent of the type of virus release. Adenovirus showed strong cytotoxicity but did not modify the membrane nor cause enzyme release. Enzyme release was associated with modification of the surface membrane due to apoptosis with poliovirus and necrosis with HSV. Consequently hepatocellular injury by viral infection did not reflect the amount or pattern of hepatocellular enzyme release.
No preview · Article · Apr 2007 · Journal of Medical Virology