RESUMEN
Two thiarubrines (dithiacyclohexadienes), which were isolated recently from species of Asteraceae, were investigated for light-mediated antiviral activity against human immunodeficiency virus (HIV-1). Both compounds (thiarubrines A and D) showed good anti-HIV activity, in micromolar concentrations, which was dependent upon UVA radiation. They showed no anti-viral activity in the dark, and only weak visible light-mediated activity, despite the significant absorbance of these compounds in the 480 nm region. The resulting inactivated virus was unable to replicate in cell cultures, as indicated by loss of cytopathogenicity, the absence of cells expressing HIV-1 antigens and lack of production of HIV-1 p24 protein. Although this antiviral activity was not as efficient as that shown by the photoactive plant thiophene, alpha-terthienyl, both thiarubrines demonstrated increased activity when the serum component of the virus stock was reduced. This suggested that a component of bovine serum interfered to some extent with the anti-HIV activity.
Asunto(s)
Alquinos/farmacología , Antivirales/farmacología , VIH-1/efectos de los fármacos , Compuestos Heterocíclicos/farmacología , Luz , Polienos/farmacología , Rayos Ultravioleta , Animales , Sangre , Bovinos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Medio de Cultivo Libre de Suero , Oscuridad , Enterovirus Humano B/efectos de los fármacos , Proteína p24 del Núcleo del VIH/metabolismo , VIH-1/crecimiento & desarrollo , Humanos , Estructura Molecular , Poliovirus/efectos de los fármacos , Poliinos , Compuestos de Azufre , Tiofenos , Células Tumorales Cultivadas , Células VeroRESUMEN
Two potent stimulators of uterine contraction, the diterpenes kaurenoic and grandiflorenic acids, were isolated from leaves of Aspilia mossambicensis. Their presence supports a hypothesis that wild chimpanzees consume Aspilia species for their pharmacological properties and may explain why female chimpanzees consume Aspilia leaves more frequently than do males. Thiarubrines were not present in any of the leaf samples collected in Mahale or Gombe National Parks, Tanzania, although these antifungal and nematocidal dithianes were found in significant amounts in roots.
Asunto(s)
Diterpenos/farmacología , Pan troglodytes , Plantas Medicinales/química , Contracción Uterina/efectos de los fármacos , Animales , Diterpenos/química , Diterpenos/aislamiento & purificación , Femenino , Cobayas , Estructura Molecular , Reproducción/efectos de los fármacosRESUMEN
5,7-dimethoxycoumarin and isopimpinellin, together with the well-known phototoxic, photo-irritant furanocoumarins psoralen and 8-methoxypsoralen, were isolated and identified from leaves and fruits of Pelea anisata H. Mann, a plant whose fruit are used in the construction of mohikana leis used in parts of the Hawaiian Islands. The presence of phototoxic furanocoumarins would explain the occurrence of photodermatitis in the wearers of the leis.
Asunto(s)
Cumarinas/aislamiento & purificación , Ficusina/aislamiento & purificación , Furocumarinas/aislamiento & purificación , Metoxaleno/análogos & derivados , Metoxaleno/aislamiento & purificación , Trastornos por Fotosensibilidad/inducido químicamente , Plantas/análisis , HumanosRESUMEN
The anti-tumour effects of the sesquiterpene lactone, parthenin was studied both in vivo and in vitro. Parthenin showed marked cytotoxic activity to P815 mastocytoma, L1210 leukemia, and M-1 rhabdomyosarcoma cells in vitro. In vivo studies showed intraperitoneal drug administration could either cure mice or increase their survival time after intraperitoneal of subcutaneous injection with tumour cells.