Sistemas precursores de cristais líquidos mucoadesivos para administração bucal de peptídeo antigelatinolítico associados à terapia fotodinâmica no tratamento do câncer bucal
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Data
2017-01-27
Autores
Calixto, Giovana Maria Fioramonti [UNESP]
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Editor
Universidade Estadual Paulista (Unesp)
Resumo
O câncer bucal é uma doença altamente incidente na população mundial, podendo provocar invalidez, deformidades faciais e morte. O tratamento de escolha é a quimioterapia e radioterapia, que causam vários efeitos adversos como xerostomia, mucosite, perda de cabelo, náusea, dores e vômitos. A administração de moléculas bioativas, como o peptídeo antitumoral CTT1, demonstrou ser um tratamento inovador e eficaz para o câncer bucal. No entanto, peptídeos apresentam baixa biodisponibilidade oral, o que diminui o desempenho clínico do tratamento. Portanto, a sua administração pela via bucal incorporado em sistemas nanoestruturados mucoadesivos precursores de cristais líquidos (SPCL) constituídos por álcool cetílico etoxilado 20 e propoxilado 5, ácido oleico e fase aquosa contendo água (FA), dispersão polimérica de quitosana (FQ), dispersão polimérica de polietilenoimina (FP) ou dispersão de quitosana associada a polietilenoimina (FPQ) surge como uma valiosa estratégia, visto que a mucosa bucal apresenta alta permeabilidade e alta irrigação sanguínea, o que pode aumentar a absorção do CTT1. Ademais, o SPCL possibilita a incorporação concomitante do CTT1 com o fotossensibilizante azul de metileno (AM), permitindo a associação da terapia fotodinâmica (TFD) à terapia peptídica antitumoral, o que pode potencializar o tratamento do câncer bucal. O objetivo do trabalho foi avaliar o potencial de SPCL mucoadesivos para administração bucal do peptídeo CTT1 associados à TFD no tratamento do câncer bucal. Os SPCL foram caracterizados por microscopia de luz polarizada (MLP), espalhamento de raios-X de baixo ângulo (SAXS), ensaios de reologia de mucoadesão e de perfil de textura in vitro, os quais evidenciaram que todas as formulações agiram como SPCL, pois formaram cristais líquidos após a adição de saliva artificial, sendo que FPQ formou um cristal líquido mais mucoadesivo e estruturado, portanto foi selecionado para a incorporação de CTT1 (FPQ-P) e AM (FPQ-AM). FPQ liberou 8% do CTT1 e 40% do AM em 24 horas, agindo como um sistema de liberação controlada. O teste de dicroísmo circular demonstrou que o peptídeo CTT1 permaneceu estável após ser incorporado em FPQ. A zimografia mostrou que o peptídeo CTT1 conseguiu inibir a ação das MMP 2 e 9; no entanto, FPQ-P não inibiu, provavelmente pela baixa taxa de liberação do peptídeo a partir do sistema. Os testes citotóxicos demonstraram que o peptídeo não influencia a viabilidade celular enquanto que os testes fotocitotóxicos in vitro parecem demonstrar que o AM incorporado na formulação é promissor para a TFD. Os testes in vivo em membrana corioalantóica do embrião da galinha (CAM) mostraram que 10% da formulação FPQ não demonstrou afetar os vasos sanguíneos da CAM. Os testes para avaliar o crescimento tumoral mostraram que o CTT1 diminuiu a formação do tumor e do número dos vasos; no entanto, quando o peptídeo foi adicionado na formulação, essa ação foi menor, o que era esperado uma vez que formulação retarda a liberação do peptídeo em 8h. Os resultados sugerem o potencial do sistema para incorporação do peptídeo CTT1 e do AM objetivando o tratamento do câncer bucal.
Oral cancer is a highly incident disease in the world population, and can cause disability, facial deformities and death. The treatment of choice is chemotherapy and radiotherapy, which cause various adverse effects like xerostomia, mucositis, hair loss, nausea, aches and vomiting. The administration of bioactive molecules, such as the antitumor peptide CTT1, has proven to be an innovative and effective treatment for oral cancer. However, peptides have low oral bioavailability, which decreases the clinical performance of the treatment. Therefore, its administration by the oral route incorporated in liquid crystal precursor (SPCL) mucoadhesive nanostructured systems consisting of ethoxylated ethoxylated 20 and propoxylated cetyl alcohol 5, oleic acid and aqueous phase containing water (FA), polymer dispersion of chitosan (CF), dispersion (FP) or polyethyleneimine-associated chitosan dispersion (FPQ) arises as a valuable strategy, since the buccal mucosa has high permeability and high blood supply, which may increase the uptake of CTT1. In addition, SPCL allows the simultaneous incorporation of CTT1 with the methylene blue photosensitizer (MA), allowing the association of photodynamic therapy (PDT) with antitumor peptide therapy, which may potentiate oral cancer treatment. The objective of this study was to evaluate the potential of mucoadhesive SPCL for buccal administration of the CTT1 peptide, as well as to evaluate the use of PDT using AM as a photosensitizer in oral cancer therapy. SPCL were characterized by polarized light microscopy (MLP), low-angle X-ray scattering (SAXS), in vitro mucoadhesion rheology and texture profile tests, which showed that all formulations acted as SPCL because (FPQ-P) and AM (FPQ-AM) were added to the liquid crystals after the addition of artificial saliva, and FPQ formed a more mucoadhesive and structured liquid crystal. FPQ released 8% of CTT1 and 40% of AM in 24 hours, acting as a sustained release system. The circular dichroism test demonstrated that the CTT1 peptide remained stable after being incorporated into FPQ. Zymography showed that the CTT1 peptide was able to inhibit the action of MMP 2 and 9; However, FPQ-P did not inhibit, probably because of the low rate of release of the peptide from the system. Cytotoxic assays have demonstrated that the peptide does not influence cell viability while in vitro photocytotoxic tests seem to demonstrate that AM incorporated into the formulation is promising for PDT. In vivo chicken embryo chorioallantoic membrane (CAM) tests showed that 10% of the FPQ formulation was not shown to affect CAM blood vessels. Tests to assess tumor growth showed that CTT1 decreased tumor and vessel number formation; However, when the peptide was added to the formulation, this action was lower, which was expected since the formulation slows the release of the peptide in 8h. The results suggest the potential of the system for the incorporation of the CTT1 peptide and AM aiming at the treatment of oral cancer.
Oral cancer is a highly incident disease in the world population, and can cause disability, facial deformities and death. The treatment of choice is chemotherapy and radiotherapy, which cause various adverse effects like xerostomia, mucositis, hair loss, nausea, aches and vomiting. The administration of bioactive molecules, such as the antitumor peptide CTT1, has proven to be an innovative and effective treatment for oral cancer. However, peptides have low oral bioavailability, which decreases the clinical performance of the treatment. Therefore, its administration by the oral route incorporated in liquid crystal precursor (SPCL) mucoadhesive nanostructured systems consisting of ethoxylated ethoxylated 20 and propoxylated cetyl alcohol 5, oleic acid and aqueous phase containing water (FA), polymer dispersion of chitosan (CF), dispersion (FP) or polyethyleneimine-associated chitosan dispersion (FPQ) arises as a valuable strategy, since the buccal mucosa has high permeability and high blood supply, which may increase the uptake of CTT1. In addition, SPCL allows the simultaneous incorporation of CTT1 with the methylene blue photosensitizer (MA), allowing the association of photodynamic therapy (PDT) with antitumor peptide therapy, which may potentiate oral cancer treatment. The objective of this study was to evaluate the potential of mucoadhesive SPCL for buccal administration of the CTT1 peptide, as well as to evaluate the use of PDT using AM as a photosensitizer in oral cancer therapy. SPCL were characterized by polarized light microscopy (MLP), low-angle X-ray scattering (SAXS), in vitro mucoadhesion rheology and texture profile tests, which showed that all formulations acted as SPCL because (FPQ-P) and AM (FPQ-AM) were added to the liquid crystals after the addition of artificial saliva, and FPQ formed a more mucoadhesive and structured liquid crystal. FPQ released 8% of CTT1 and 40% of AM in 24 hours, acting as a sustained release system. The circular dichroism test demonstrated that the CTT1 peptide remained stable after being incorporated into FPQ. Zymography showed that the CTT1 peptide was able to inhibit the action of MMP 2 and 9; However, FPQ-P did not inhibit, probably because of the low rate of release of the peptide from the system. Cytotoxic assays have demonstrated that the peptide does not influence cell viability while in vitro photocytotoxic tests seem to demonstrate that AM incorporated into the formulation is promising for PDT. In vivo chicken embryo chorioallantoic membrane (CAM) tests showed that 10% of the FPQ formulation was not shown to affect CAM blood vessels. Tests to assess tumor growth showed that CTT1 decreased tumor and vessel number formation; However, when the peptide was added to the formulation, this action was lower, which was expected since the formulation slows the release of the peptide in 8h. The results suggest the potential of the system for the incorporation of the CTT1 peptide and AM aiming at the treatment of oral cancer.
Descrição
Palavras-chave
Nanotecnologia farmacêutica, Sistemas de liberação de fármacos, Cristais líquidos, Administração bucal, Polímeros catiônicos, Mucoadesão, Peptídeos, Câncer bucal, Terapia fotodinâmica, Pharmaceutical nanotechnology, Drug delivery systems, Liquid crystals, Buccal administration, Cationic polymers mucoadhesion, Peptides, Oral cancer, Photodynamic therapy, Photodynamic therapy