RESUMEN
A polyphenol-rich extract from the aerial roots of the medicinal plant Geranium sanguineum L. (PC) protected mice from mortality in the experimental influenza A/Aichi/2/68 (H3N2) virus infection. To provide evidence how a maximum therapeutic benefit can be derived of this preparation, it was inoculated by 6 different routes. It was found that the aerosol application of PC was highly effective. In the dose 5.4 mg/ml, applied according to a prophylactic-therapeutic schedule, the extract exhibited a marked protective effect. The protective index reached the value of 70.1% and the mean survival time was prolonged with 2.9-4.9 days. The lung infectious virus titres and the lung consolidation of virus-infected and PC-treated animals were all reduced in comparison with control. The application of PC according to schedules, excluding the pretreatment of mice, proved that this condition was essential for protection.
Asunto(s)
Antivirales/química , Antivirales/uso terapéutico , Geranium/química , Subtipo H3N2 del Virus de la Influenza A , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/virología , Aerosoles , Animales , Antivirales/toxicidad , Línea Celular , Embrión de Pollo , Efecto Citopatogénico Viral/efectos de los fármacos , Femenino , Geranium/toxicidad , Dosificación Letal Mediana , Masculino , Ratones , Ratones Endogámicos ICR , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Análisis de Supervivencia , SuspensionesRESUMEN
The synergistic effect shown by the combination of a natural product, polyphenolic complex (PC) isolated from Geranium sanguineum L., and rimantadine (R) in vitro and in ovo [7], encouraged us to continue these studies by in vivo testing. A marked protective effect in experimental influenza virus A (H3N2) infection in mice was found when PC was applied nasally (i.n.) (1.0 mg/kg) only once 6 h before infection in combination with R applied orally in concentration 10.5 and 2.5 mg/kg 2h before and 2.24 and 48 h after viral inoculation (PI = 72.55%, 55% and 57.8% respectively).
Asunto(s)
Antivirales/uso terapéutico , Flavonoides , Virus de la Influenza A , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Fenoles/uso terapéutico , Extractos Vegetales/uso terapéutico , Polímeros/uso terapéutico , Rimantadina/uso terapéutico , Animales , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Quimioterapia Combinada , Virus de la Influenza A/efectos de los fármacos , Ratones , Polifenoles , Factores de TiempoRESUMEN
The antiviral effect of rimantadine and isoprinosine applied in combination against fowl plague virus (FPV) in cell cultures of chick embryo fibroblasts and in experimental influenza infection in mice has been studied. Isoprinosine does not inhibit the reproduction of FPV when given alone and does not increase the antiviral activity of rimantadine. After oral application of both substances according to an appropriate scheme in mice infected with influenza virus A/Aichi (N3N2), an increase in the antiviral effect with an index of protection by 12% higher than the theoretically calculated one for additive effect was established. The results suggest that the combined effect is synergic.