ABSTRACT
Sporotrichosis is the most frequent subcutaneous mycosis in the world and its increasing incidence has led to the search for new therapeutic options for its treatment. In this study, we demonstrated that three structural analogues of miltefosine (TCAN26, TC19, and TC70) showed inhibitory activity against Sporothrix schenckii sensu stricto and that TCAN26 was more active in vitro than miltefosine against several isolates. Scanning electron microscopy showed that S. schenckii exposure to TCAN26 resulted in cells that were slightly more elongated than untreated cells. Transmission electron microscopy showed that TCAN26 treatment induced loss of the regular cytoplasmic electron-density and altered the cell envelope (disruption of the cell membrane and cell wall, and increased cell wall thickness). Additionally, TCAN26 concentrations required to kill S. schenckii cells were lower than concentrations that were cytotoxic in mammalian cells, and TCAN26 was more selective than miltefosine. Thus, the adamantylidene-substituted alkylphosphocholine TCAN26 is a promising molecule for the development of novel antifungal compounds, although further investigations are required to elucidate the mode of action of TCAN26 in S. schenckii cells.
Subject(s)
Adamantane/pharmacokinetics , Antifungal Agents/pharmacology , Phosphorylcholine/analogs & derivatives , Sporothrix/drug effects , Adamantane/chemistry , Antifungal Agents/chemistry , Cell Membrane/drug effects , Drug Substitution , Humans , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Phosphorylcholine/chemistry , Phosphorylcholine/pharmacology , Sporothrix/classification , Sporothrix/ultrastructureABSTRACT
Sporotrichosis is the most frequent subcutaneous mycosis in the world and its increasing incidence has led to the search for new therapeutic options for its treatment. In this study, we demonstrated that three structural analogues of miltefosine (TCAN26, TC19, and TC70) showed inhibitory activity against Sporothrix schenckii sensu stricto and that TCAN26 was more active in vitro than miltefosine against several isolates. Scanning electron microscopy showed that S. schenckii exposure to TCAN26 resulted in cells that were slightly more elongated than untreated cells. Transmission electron microscopy showed that TCAN26 treatment induced loss of the regular cytoplasmic electron-density and altered the cell envelope (disruption of the cell membrane and cell wall, and increased cell wall thickness). Additionally, TCAN26 concentrations required to kill S. schenckii cells were lower than concentrations that were cytotoxic in mammalian cells, and TCAN26 was more selective than miltefosine. Thus, the adamantylidene-substituted alkylphosphocholine TCAN26 is a promising molecule for the development of novel antifungal compounds, although further investigations are required to elucidate the mode of action of TCAN26 in S. schenckii cells.
Subject(s)
Humans , Adamantane/pharmacokinetics , Antifungal Agents/pharmacology , Phosphorylcholine/analogs & derivatives , Sporothrix/drug effects , Adamantane/chemistry , Antifungal Agents/chemistry , Cell Membrane/drug effects , Drug Substitution , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Phosphorylcholine/chemistry , Phosphorylcholine/pharmacology , Sporothrix/classification , Sporothrix/ultrastructureABSTRACT
A novel LC-MS/MS method was developed for the quantification of vildagliptin in an aqueous matrix. The method was successfully validated, meeting all the requisites of US Food and Drug Administration guide for a bioanalytical method. The developed method presented a limit of quantification of 10 ng/mL and the range of concentration achieved was 10-1875 ng/mL. The injection volume necessary was only 10 µL, and retention time was 4.60 min. The mobile phase employed was methanol-ammonium acetate 5 mm (95:5). The stability of the drug was evaluated in the different conditions through which the samples passed. A pharmacokinetic experiment was conducted with diabetic male Wistar rats, and the concentration of drug in liver was evaluated through a microdialysis technique. The perfusion fluid employed was ultrapure water. The dose administrated was 50 mg/kg and the method allowed the quantification of vildagliptin for more than three half lives, successfully characterizing the pharmacokinetic profile when the developed method was applied. This is the first report on the tissue pharmacokinetics of a DPP-4 inhibitor and could contribute to drug dosage optimization in the future.