Thierllen Barroso Graciano1, Tatielle Soares Coutinho1, Camila Beatriz Cressoni1, Cristhiane de Paula Freitas1, Maria Bernadete Riemma Pierre2, Sanívia Aparecida de Lima Pereira3, Marcos Massao Shimano4, Renata Cristina da Cunha Frange1, Maria Teresa Junqueira Garcia5. 1. School of Pharmacy, University of Uberaba (UNIUBE), Av. Nenê Sabino, 1801, Bairro Universitário, CEP: 38055-500, Uberaba, MG, Brazil. 2. Faculty of Pharmacy, Federal University of Rio de Janeiro (UFRJ), Av. Carlos Chagas Filho, 373, CEP: 21.941.590, Rio de Janeiro, RJ, Brazil. 3. Laboratory of Biopathology and Molecular Biology, University of Uberaba (UNIUBE), Av. Nenê Sabino, 1801, Bairro Universitário, CEP: 38055-500, Uberaba, MG, Brazil. 4. Department of Mechanical Engineering, Federal University of Triangulo Mineiro (UFTM), Av. Frei Paulino, 30, Bairro Abadia, CEP: 38025-180, Uberaba, MG, Brazil. 5. School of Pharmacy, University of Uberaba (UNIUBE), Av. Nenê Sabino, 1801, Bairro Universitário, CEP: 38055-500, Uberaba, MG, Brazil; School of Pharmacy and Biochemistry, Federal University of São Paulo (UNIFESP), Campus Diadema, Rua São Nicolau, 210, CEP: 09913-030, Diadema, SP, Brazil. Electronic address: mtjgarcia@yahoo.com.
Abstract
BACKGROUND: Photodynamic therapy (PDT) is an emerging treatment that has demonstrated potential for the clinical treatment of buccal cancer. It is based on the photoactivation of a photosensitizer (PS) when irradiated by light at a specific wavelength. The light-excited PS generates reactive oxygen species that cause the destruction of tumor cells by apoptosis or necrosis. Toluidine Blue O (TBO) is a PS that has shown potential for PDT in cancer treatment. However, saliva and mechanical activities quickly remove the PS from the surface of the buccal mucosa. Therefore, the bioavailability of PS at the surface of target tissues is reduced. The aim of this study was to evaluate the potential of chitosan (CH) gels in TBO delivery to buccal tissue. METHODS: CH gels were obtained at different concentrations and their physico-chemical properties (pH and rheology), mucoadhesion, in vitro release profile, in vivo retention and in vivo efficacy by the ability to induce cell apoptosis were evaluated. RESULTS: CH-based mucoadhesive gels optimized the release and adherence of preparations at the target site. Specifically, 4% (w/w) CH gel showed adequate properties for buccal use, such as pH value, mucoadhesion, pseudoplastic behavior, extended release, minimal permeation and higher TBO retention by the mucosa. In vivo studies showed the potential of the gel to enhance TBO retention and induce cell apoptosis after laser irradiation. CONCLUSION: 4% (w/w) CH based mucoadhesive gel can be explored as a TBO delivery system in the PDT of oral cancer.
BACKGROUND: Photodynamic therapy (PDT) is an emerging treatment that has demonstrated potential for the clinical treatment of buccal cancer. It is based on the photoactivation of a photosensitizer (PS) when irradiated by light at a specific wavelength. The light-excited PS generates reactive oxygen species that cause the destruction of tumor cells by apoptosis or necrosis. Toluidine Blue O (TBO) is a PS that has shown potential for PDT in cancer treatment. However, saliva and mechanical activities quickly remove the PS from the surface of the buccal mucosa. Therefore, the bioavailability of PS at the surface of target tissues is reduced. The aim of this study was to evaluate the potential of chitosan (CH) gels in TBO delivery to buccal tissue. METHODS: CH gels were obtained at different concentrations and their physico-chemical properties (pH and rheology), mucoadhesion, in vitro release profile, in vivo retention and in vivo efficacy by the ability to induce cell apoptosis were evaluated. RESULTS: CH-based mucoadhesive gels optimized the release and adherence of preparations at the target site. Specifically, 4% (w/w) CH gel showed adequate properties for buccal use, such as pH value, mucoadhesion, pseudoplastic behavior, extended release, minimal permeation and higher TBO retention by the mucosa. In vivo studies showed the potential of the gel to enhance TBO retention and induce cell apoptosis after laser irradiation. CONCLUSION: 4% (w/w) CH based mucoadhesive gel can be explored as a TBO delivery system in the PDT of oral cancer.
Authors: Juan Zhang; Chengshi Jiang; João Paulo Figueiró Longo; Ricardo Bentes Azevedo; Hua Zhang; Luis Alexandre Muehlmann Journal: Acta Pharm Sin B Date: 2017-09-22 Impact factor: 11.413
Authors: Mariana Q Mesquita; Cristina J Dias; Maria G P M S Neves; Adelaide Almeida; M Amparo F Faustino Journal: Molecules Date: 2018-09-21 Impact factor: 4.411