Assuntos
Analgésicos Opioides/uso terapêutico , Hiperalgesia/tratamento farmacológico , Meperidina/uso terapêutico , Oxicodona/uso terapêutico , Receptores de Quimiocinas/antagonistas & inibidores , Animais , Benzilaminas , Ciclamos , Avaliação Pré-Clínica de Medicamentos/métodos , Sinergismo Farmacológico , Quimioterapia Combinada , Compostos Heterocíclicos/uso terapêutico , Masculino , Maraviroc/uso terapêutico , Ratos Sprague-DawleyRESUMO
Inhibition of the necrotizing hyaluronidase, phospholipase A2 and protease enzymes in four snake venoms by crude water and ethanol extracts of 88 plant species used against snakebites in traditional Chinese medicine was measured. High-resolution hyaluronidase inhibition profiles were constructed for the 22 plants showing highest hyaluronidase inhibition, and the results were used to guide subsequent structural analysis towards specific hyaluronidase inhibitors. Structural analysis was performed by high-performance liquid chromatography, high-resolution mass spectrometry, solid-phase extraction and nuclear magnetic resonance spectroscopy, i.e., HPLC-HRMS-SPE-NMR. This allowed identification of four non-tannin inhibitors, i.e., lansiumamide B (6) from Clausena excavata Burm.f., myricetin 3-O-ß-D-glucopyranoside (7) from Androsace umbellata (Lour.) Merr., and vitexin (8) and 4',7-dihydroxy-5-methoxyflavone-8-C-ß-D-glucopyranoside (9) from Oxalis corniculata L. Absolute configuration of 2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide (1) was determined using the Mosher method, which revealed two enantiomers, i.e., (2S,3R)-2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide and (2R,3S)-2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide with a ratio of 7:3.
Assuntos
Hialuronoglucosaminidase/antagonistas & inibidores , Inibidores de Fosfolipase A2/isolamento & purificação , Inibidores de Fosfolipase A2/farmacologia , Mordeduras de Serpentes/tratamento farmacológico , Taninos/isolamento & purificação , Taninos/farmacologia , Apigenina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Inibidores de Glicosídeo Hidrolases/química , Hialuronoglucosaminidase/metabolismo , Medicina Tradicional Chinesa , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oxalidaceae/química , Inibidores de Fosfolipase A2/química , Extratos Vegetais/química , Extração em Fase Sólida , Taninos/químicaRESUMO
The purpose of this study was to determine whether Candida albicans, and other Candida spp. responsible for HIV-associated candidosis, could be sensitised to killing by low-power laser light. Suspensions of C. albicans were treated with a number of potential photosensitisers, exposed to laser light from a Helium/Neon (HeNe) or Gallium aluminium arsenide (GaAs) laser for 120 s and survivors enumerated. Toluidine blue O (TBO), thionin and crystal violet were able to sensitise the yeast to killing by light from the HeNe laser (energy dose = 876 mJ at a density of 66.36 J/cm2), the kills achieved being 6.8 x 10(6) cfu/ml, 3.1 x 10(6) cfu/ml and 1.3 x 10(6) cfu/ml respectively. TBO was also able to sensitise several other Candida spp. to killing by HeNe laser light. Dihaematoporphyrin ester was not an effective photosensitiser under the conditions employed. Methylene blue, but not aluminium disulphonated phthalocyanine, was able to sensitise C. albicans to killing by light from the GaAs laser (energy dose 1.32 J at a density of 2.04 J/cm2). The viability of the yeast was not affected by exposure to laser light in the absence of the photosensitisers. As killing of dye-sensitised C. albicans, and other Candida spp., could be achieved by exposure to low-power laser light for short periods of time, this approach merits further investigation as a potential therapeutic modality for HIV-associated candidosis.