Assessment of β-lapachone loaded in lecithin-chitosan nanoparticles for the topical treatment of cutaneous leishmaniasis in L. major infected BALB/c mice.

Patients affected by cutaneous leishmaniasis need a topical treatment which cures lesions without leaving scars. Lesions are produced not only by the parasite but also by an uncontrolled and persistent inflammatory immune response. In this study, we proposed the loading of β-lapachone (β-LP) in lecithin-chitosan nanoparticles (NP) for targeting the drug to the dermis, where infected macrophages reside, and promote wound healing. Although the loading of β-LP in NP did not influence the drug antileishmanial activity it was critical to achieve important drug accumulation in the dermis and permeation through the skin. When topically applied in Leishmania major infected BALB/c mice, β-LP NP achieved no parasite reduction but they stopped the lesion progression. Immuno-histopathological assays in CL lesions and quantitative mRNA studies in draining lymph nodes confirmed that β-LP exhibited anti-inflammatory activity leading to the down-regulation of IL-1β and COX-2 expression and a decrease of neutrophils infiltrate. FROM THE CLINICAL EDITOR: Cutaneous leishmaniasis often leaves patients with unsightly scars due to the body's inflammatory response to the infection. The authors in this paper described topical treatment using β-lapachone (β- LP) loaded in lecithin-chitosan nanoparticles (NP) in an animal model. Results confirmed the reduction of inflammatory response without affecting the parasite killing efficacy. These findings would pave way for further clinical testing in the near future.