Comparison of protocols in methylene blue-mediated photodynamic inactivation on cutaneous leishmaniasis in a murine model using real time bioluminescence
Carregando...
Data
Data de publicação
2017
Autores IPEN
Orientador
Título da Revista
ISSN da Revista
Título do Volume
É parte de
É parte de
É parte de
É parte de
WORLD CONGRESS ON LEISHMANIASIS, 6th
Exportar
Resumo
1 Background
Leishmaniasis is a chronic disease developed by parasites of the genus Leishmania. Cutaneous leishmaniasis
(CL) has several different forms including destructive and ulcerated lesions. The available treatments are
limited because of side effects, resistance and toxicity. Photodynamic therapy (PDT) has been explored as an
alternative treatment once it is less expensive and no reports about resistance have been described. The aim of
this work was to evaluate two protocols of methylene blue (MB)-mediated PDT on CL induced in mice using
real time bioluminescence. In addition, we monitored lesion size progression and hyperalgesia.
2 Methods
Promastigotes of L. (L) amazonensis transgenic line expressing luciferase were used. Twelve BALB/c mice
were infected in the left footpad with 1.106 promastigotes. After 4 weeks, mice were randomly assigned to
experimental groups (n=4): Control (non-treated), G1 and G2 submitted to one and two PDT sessions,
respectively. The second session was performed 24h after the first. PDT was performed using a red LED (λ=
660±22 nm), MB (100μM) and 150J/cm² fluence. Disease progression was evaluated once a week by
measuring lesion size with a caliper and hyperalgesia with von Frey filaments. Parasite burden was evaluated
through luciferase detection by bioimaging, every day, in the first 96h and then for the next 4 weeks. Prior to
imaging, mice received 75mg/kg luciferin, intraperitoneally. Results were quantified with proper software,
expressing the number of photons/s/cm2. Statistically significant differences were considered when p<0.05.
3 Results
Statistically significant lesion size reduction was observed after 2 weeks post PDT compared to G1 and control
groups. In 4 weeks, G2 demonstrated to be clinically more effective and no ulcer signs were detected.
Hyperalgesia revealed a positive outcome after 2 weeks, with 50% nociceptive stimulus decrease. In 3 weeks
there was a 75% reduction in G2, suggesting that 2 sessions were more efficient. Parasite burden was lower in
the first 24h and 72h in both treated groups. Besides, G2 demonstrated statistically significant parasite burden
reduction 96h after PDT compared to control.
4 Conclusions
The present study demonstrated that PDT reduced lesion size and hyperalgesia in BALB/c mice, suggesting
that therapy probably influenced the inflammatory process. However, further studies are required to deep
understanding about PDT mechanisms in cutaneous leishmaniasis treatment.
Como referenciar
CABRAL, FERNANDA V.; RIBEIRO, MARTHA S.; SAUTER, ISMAEL P.; VELIZ, MAURO J.C. Comparison of protocols in methylene blue-mediated photodynamic inactivation on cutaneous leishmaniasis in a murine model using real time bioluminescence. In: WORLD CONGRESS ON LEISHMANIASIS, 6th, May 16-20, 2017, Toledo, Spain. Abstract... p. 749-749. Disponível em: http://repositorio.ipen.br/handle/123456789/27932. Acesso em: 26 Mar 2026.
Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.