Caesalpinia spinosa (Molina) Kuntze: A new promise for the topical treatment of cutaneous leishmaniasis

Abstract

Given the need to develop new drugs for the treatment of cutaneous leishmaniasis, not only effective and safe, but also more widely accepted by patients, easily administered in rural settings and cheaper, in the present study the in vitro and in vivo therapeutic potential and cytotoxicity profile of an ethanolic and a glycolic extracts obtained from the branches of Caesalpinia spinosa (Molina) Kuntze and their respective formulations (lotion and emulsion) were evaluated. Finally, the usefulness of the two formulations as topical treatment was validated in 10 patients with uncomplicated CL. Both extracts were active against L. braziliensis at concentrations <22 μg / mL, with low toxicity in U-937 and HL60 cells when administered pure and for Hep G2 and Detroit 551 cells when administered at concentrations <20%. Neither the extracts nor the formulations were irritating or did not cause any corrosive or any other sign of dermal toxicity. The exposure of fibroblasts to the glycolic extract and to the formulations favored the migration of fibroblasts and repair of the monolayer after 16 h of contact, allowing the closing of the gap between 33.9% and 70.9%. Both the extracts and the formulations favored the complete cure of the hamsters with cutaneous leishmaniasis in percentages greater than 80%. After being applied to the skin, lotion and emulsion are absorbed, penetrate, and although they can be detected in plasma up to 24 hours (the lotion) or 6 hours (the emulsion) after application, most of the products it is retained in the skin. Lastly, the treatment of 10 patients with the lotion and the emulsion showed the complete healing of the lesions with the repair of the damaged skin and without adverse effects. In conclusion, the results demonstrate leishmanicidal and healing properties for C. spinosa that give it the potential to become a safe alternative for the local treatment of cutaneous leishmaniasis. It is necessary to validate these results in controlled clinical trials and determine the efficacy and safety of treatment with C. spinosa phytotherapeutic products.