RESUMEN
Staphylococcus aureus infections are a severe health problem due to the high mortality rate. Conventional treatment of these infections is via the administration of antibiotics. However, its indiscriminate use can select resistant microorganisms. Thus, it is necessary to develop alternatives for antibiotic therapy. Antimicrobial Photodynamic Therapy (aPDT), a therapeutic method that associates a photosensitizer (PS), a light source with adequate wavelength to the PS, interacts with molecular oxygen generating reactive oxygen species responsible for cell inactivation, is a viable alternative. This work aimed to analyze, in vitro and in vivo, the action of aPDT with PS Photodithazine® (PDZ) on the methicillin-resistant S. aureus (MRSA) strain. In the in vitro method, the S. aureus biofilm was incubated with PDZ at 50 and 75 µg.mL-1 for 15 min, adopting the light dose of 25, 50, and 100 J/cm2. In addition, PS interaction, formation of reactive oxygen species (ROS), bacterial metabolism, adhesion, bacterial viability, and biofilm structure were evaluated by scanning electron microscopy. Subsequently, the strain was inoculated into models of Galleria mellonella, and the survival curve, health scale, blood cell analysis, and CFU/mL of S. aureus in the hemolymph were analyzed after aPDT. In the in vitro results, bacterial reduction was observed in the different PDZ concentrations, highlighting the parameters of 75 µg.mL-1 of PDZ and 100 J/cm2. As for in vivo results, aPDT increased survival and stimulated the immune system of G. mellonella infected by S. aureus. aPDT proved effective in both models, demonstrating its potential as an alternative therapy in treating MRSA bacterial infections.
Asunto(s)
Antiinfecciosos , Glucosamina/análogos & derivados , Staphylococcus aureus Resistente a Meticilina , Fotoquimioterapia , Animales , Staphylococcus aureus , Especies Reactivas de Oxígeno/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Antiinfecciosos/farmacología , Biopelículas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/química , Modelos TeóricosRESUMEN
O melão (Cucumis melo L.) é uma fruta muito apreciada por suas qualidades e sua produção vem crescendo e ganhando espaço no mercado nacional e internacional. Em regiões como o Noroeste do Rio Grande do Sul, destaca-se como uma nova alternativa de renda para vários agricultores. Neste contexto, o presente trabalho teve como objetivo analisar o potencial fitoquímico de alguns cultivares de melão da região Noroeste do Rio Grande do Sul. A análise fitoquímica utilizando como farmacógeno as folhas, foi realizada para a verificação da presença de metabólitos secundários, tais como: saponinas, cumarinas, cardiotônicos, cianogenéticos, alcalóides, taninos, antraquinonas, flavonoides, e óleos voláteis. Também foi avaliado o teor de suco a partir dos frutos. Dentre os cinco cultivares analisados, Gaúcho, Imperial, Hy Mark, Magelan, e Cantaloupe, o cultivar Gaucho apresentou a maior variedade em metabólitos secundários. Na avaliação do teor de suco a cultivar Magelan se destacou em comparação às demais cultivares testadas.
The melon (Cucumis melo L.) is a fruit highly appreciated for its qualities and its production has been growing and gaining space in the national and in the international market. In regions like the northwest of Rio Grande do Sul - Brazil, it stands out as a new income alternative for farmers. In this context, this study aimed to analyze the phytochemical potential of some melon cultivars in the northwest region of Rio Grande do Sul. The phytochemical analysis, using the leaves as pharmacogen, was performed to verify the presence of secondary metabolites such as saponins, coumarins, cardiac glycosides, cyanogenetic glicosides, alkaloids, tannins, anthraquinones, flavonoids and volatile oils. The juice content from the fruits was also evaluated. Among the five analyzed cultivars, Gaucho, Imperial, Hy Mark, Magelan and Cantaloupe, cultivar Gaucho had the greatest variety of secondary metabolites. In the assessment of the juice content, cultivar Magelan was superior compared to the remaining tested cultivars.