DESENVOLVIMENTO TECNOLÓGICO DE NANOPARTÍCULAS DE ALBUMINA CONTENDO ANFOTERICINA B E APLICAÇÃO EM MODELO IN VITRO E IN VIVO DE LEISHMANIOSE CUTÂNEA

• Autor(a) principal: CASA, DIANI MEZA
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do UNICENTRO
• Texto Completo: http://tede.unicentro.br:8080/jspui/handle/jspui/671
• topic: nanopartículas; anfotericina B; leishmaniose cutânea; nanoparticles; amphotericin B; cutaneous leishmaniasis; CIENCIAS DA SAUDE::FARMACIA

Leishmaniasis is an infectious disease caused by protozoa of the genus Leishmania sp. Treatment of this is far from ideal because it requires the administration of toxic drugs poorly tolerated and it does not successfully treat the intracellular nature of the parasite infection and the disseminated locations. Amphotericin B (AmB) is currently the second choice drug for the treatment of leishmaniasis, but has severe side effects, particularly nephrotoxicity and hematotoxicity, which limit their use. Based on the concepts of nanotechnology, the present study has developed nanoparticles (NP's) bovine serum albumin (BSA) containing AmB, in order to reduce its toxicity in human cells and evaluate their therapeutic efficacy. The NP's were successfully obtained by the coacervation method, the quantification of encapsulated drug performed by High Performance Liquid Chromatography (HPLC) revealed an encapsulation efficiency of 98.3 ± 0.71%. The mean diameter was valued by Photon Correlation Spectroscopy and pointed to 173 ± 5 nm with a polydispersity index of 0.3 ± 0.01. The formulation was also characterized by transmission electron microscopy showed homogeneous and smaller than 100 nm. The zeta potential was measured weekly for two months and found a constant surface charge of about -45 mV which confirms the stability of the developed formulation. By UV/Visible spectroscopy was determined state of molecular aggregation of the proposed formulation and identified which, unlike the AmB-deoxycholate (AmB-Deoxy), it is in the monomeric state, which makes for a less toxic potential. Other characterization methods such as infrared spectroscopy and differential scanning calorimetry were conducted and highlighted the physical and chemical identity of the sample. The in vitro release kinetics experiment also performed, showed of second order profile where the release was 50% AFB NP's from the end of 5 days. The in vitro evaluation of toxicity of NP's AmB performed on human erythrocytes at a concentration of 25 and 50 μg/ml AmB and compared to free the same concentrations at 72 h showed that the percentage of hemolysis induced by 5% NP's not exceeded while the free AmB haemolysed 100% of the cells in the first hour test under the same conditions, in both concentrations. Another study cytotoxicity was assessed in the J774.A1 macrophage lineage and CC50 revealed a 0.68 ± 0.2 μg/mL for AmB-Deoxy and 77.8 ± 0.25 μg/ml for the formulation of AmB NP's. Two studies for efficacy in vitro against L. amazonensis were conducted, one in which the promastigotes showed an IC50 of 0.231 and 39.1 μg/ml for the AmB-Deoxy and AmB NP's, respectively, and, in forms other intracellular amastigotes which gave IC50 of 0.247 μg/mL for AmB-Deoxy and 4.2 μg/ml for AmB NP's. In the in vivo efficacy trial against of cutaneous leishmaniasis (CL) model in mice was found that the formulation developed reduced the lesion in the same proportion as the AmB-Deoxy, however, histological analysis showed damage in practically all evaluated organs of the group treated with AmB-Deoxy and no toxic effects in animals treated with AmB NP's. The results appoint the AmB NP's as potential controlled drug release systems, keeping the against leishmania activity and minimizing its cytotoxicity compared to the commercial standard, standing out as a promising strategy for the treatment of CL.