RESUMO
In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) membrane supplemented with latex proteins (LP) displaying wound healing activity, and its efficacy as a delivery system was demonstrated. Here, we report on aspects of the mechanism underlying the performance of the PVA-latex protein biomembrane on wound healing. LP-PVA, but not PVA, induced more intense leukocyte (neutrophil) migration and mast cell degranulation during the inflammatory phase of the cicatricial process. Likewise, LP-PVA induced an increase in key markers and mediators of the inflammatory response (myeloperoxidase activity, nitric oxide, TNF, and IL-1ß). These results demonstrated that LP-PVA significantly accelerates the early phase of the inflammatory process by upregulating cytokine release. This remarkable effect improves the subsequent phases of the healing process. The polyvinyl alcohol membrane was fully absorbed as an inert support while LP was shown to be active. It is therefore concluded that the LP-PVA is a suitable bioresource for biomedical engineering.
Assuntos
Calotropis , Portadores de Fármacos , Látex/farmacologia , Membranas Artificiais , Proteínas de Plantas/farmacologia , Álcool de Polivinil/química , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos Penetrantes/tratamento farmacológico , Administração Cutânea , Animais , Calotropis/química , Degranulação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Composição de Medicamentos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Látex/isolamento & purificação , Ativação de Macrófagos/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Mastócitos/patologia , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Peroxidase/metabolismo , Fitoterapia , Proteínas de Plantas/isolamento & purificação , Plantas Medicinais , Pele/lesões , Pele/metabolismo , Pele/patologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Ferimentos Penetrantes/metabolismo , Ferimentos Penetrantes/patologiaRESUMO
OBJECTIVE AND DESIGN: Laticifer proteins (LP) of Calotropis procera were fractionated by ion-exchange chromatography, and the influence of a sub-fraction (LP(PI)) on the inflammatory response of Swiss mice challenged by Salmonella enterica Ser. Typhimurium was investigated. METHODS: Mice (n = 10) received LP(PI) (30 or 60 mg/kg) in a single inoculum by the intraperitoneal route 24 h before infection. To investigate the relevance of the proteolytic activity, three additional groups were included: the first one received heat-treated LP (30 mg/kg-30 min at 100 °C), the second received LP (30 mg/kg) inactivated by iodoacetamide, and a control group received only phosphate-buffered saline (PBS). RESULTS: The survival rate reached 100 % in mice treated with LP(PI) and was also observed with the other treatment, whereas the PBS group died 1-3 days after infection. The neutrophil infiltration into the peritoneal cavity of pretreated mice was enhanced and accompanied by high bacterial clearance from the bloodstream. Tumor necrosis factor-alpha mRNA transcripts, but not interferon-gamma, were detected early in spleen cells of pretreated mice after infection; however, the nitric oxide contents in the bloodstream were decreased in comparison to the PBS group. CONCLUSIONS: The inflammatory stimulus of C. procera proteins increased phagocytosis and balanced the nitric oxide release in the bloodstream, preventing septic shock induced by Salmonella infection.
