Photodynamic Therapy With Bengal Rose and Derivatives Against Leishmania amazonensis

Abstract Introduction: The treatment of cutaneous leishmaniasis (CL) is based primarily on the use of pentavalent antimonials, which may lead to many side effects limiting their use. Photodynamic therapy (PDT) is an alternative for the treatment of CL, and some xanthene dyes have the potential for use in PDT.Methods: The xanthenes rose bengal B (RB) and its derivatives rose bengal methyl ester (RBMET), and butyl ester (RBBUT) were analyzed for leishmanicidal activity against promastigotes and intracellular amastigotes of Leishmania amazonensis. Cytotoxicity was assessed in J۷۷۴.A۱ macrophages.Results: RB derivates RBMET (IC۵۰ ۹.۸۳ μM), and RBBUT (IC۵۰ ۴۵.۰۸ μM) showed leishmanicidal activity, however, were toxic to J۷۷۴.A۱ macrophages, resulting in low selectivity index.Conclusion: The RBMET and RBBUT showed to be effective against the L. amazonensis and the low selectivity index presented may not be a limitation for their use in PDT to CL treatment. Keywords: Cutaneous leishmaniasis Photodynamic therapy Leishmania amazonensis Xanthenes Rose Bengal B.