Emulgel based on amphotericin B and bacuri butter (Platonia insignis Mart.) for the treatment of cutaneous leishmaniasis: characterization and in vitro assays

Abstract

Objective: This work aimed to develop and characterize a topical emulgel of amphotericin B (AmB) with bacuri butter (Platonia insignis Mart.) and evaluate its antileishmanial activity using in vitro assays.

Significance: Leishmaniasis is considered an infectious disease, with high incidence and capacity to produce deformities. The first-line treatment recommended by WHO, with pentavalent antimonials, is aggressive and very toxic. Therefore, the development of topical treatments can emerge as a promising and less offensive alternative.

Methods: The developed formulations were evaluated for organoleptic characteristics, centrifugation resistance, globule size, pH, electrical conductivity, viscosity, spreadability, drug content, preliminary stability, in vitro release profile, evaluation of antileishmanial activity using promastigotes forms of Leishmania major as infecting agents, macrophage cytotoxicity and selectivity index (IS).

Results: Formulated emulsions presented organoleptic characteristics compatible with its constituents; pH values were suitable for topical application, ranging from 4.73 to 5.02; introduced non-Newtonian shear thinning system; drug content was within the established standards, and the most suitable kinetic model of release was the first order. Regarding the in vitro assays, formulations containing both 1% and 3% of AmB presented similar outcomes, indicating a synergism between the bacuri butter and the drug, possibly showing a reduction on cytotoxicity to host cells.

Conclusions: It was concluded that the formulations developed showed promising antileishmanial action and high potential for topical use.

Keywords:

• Biological products
• cytotoxicity
• drug stability
• leishmaniasis
• quality control

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors are thankful to the Federal University of Piauí (Teresina, Brazil) for providing necessary facilities and the Research Program for SUS (PPSUS) for the financial support (Edict – FAPEPI/MS-DECIT/CNPq/SESAPI number 002/2016). They also thank the Pharmacy School of this same University and the Antileishmanial laboratory from the Medicinal Plant Research Nucleus for all the support provided during the developed tests.