Formulation and Characterization of a Self-Emulsifying Drug Delivery system (SEDDS) of Curcumin for the Topical Application in Cutaneous and Mucocutaneous Leishmaniasis.

BACKGROUND: Leishmaniasis, which is classified by the World Health Organization (WHO) as one of the neglected tropical diseases (NTDS) faces several challenges in terms of successful chemotherapy and novel drug developments.

OBJECTIVE: The aim of the present study was to develop a Self-Emulsifying Drug Delivery System (SEDDS) for the hydrophobic polyphenol pigment curcumin to enable it for its potential use in cutaneous and mucocutaneous leishmaniasis.

METHODS: Two Curcumin-loaded formulations SNEDD-A and B, were developed. Both were characterized by the droplet size, PDI and zeta potential and evaluated for the cytotoxicity on Caco-2 cell lines and through hemolysis test on red blood cells. The spreading potential of the formulations was checked over buccal mucosa and damaged skin model. Anti-leishmanial activities were performed against promastigote, axenic amastigote and macrophage harbored amastigotes of Leishmania tropica parasite.

RESULTS: SNEDDS-A and B had minor differences in physical characteristics. In toxicological assay, the viability of the Caco-2 cells was 87.5 % for SNEDDS-A and 88.9% for SNEDDS-B while both caused 1-2% hemolysis. Both had remarkable spreading potential, covering 8cm2 of buccal mucosa and damaged the skin less than 45 minutes. The anti-leishmanial activities of the SNEDDS-A in terms of IC50 were 0.13 µg/ml and 0.25µg/ml against promastigote and amastigote respectively while IC50 values of SNEDDS-B were 0.18µg/ml and 0.27µg/ml against promastigote and amastigote respectively. Both the formulations killed 100% of the macrophage harbored Leishmania tropica parasites at a concentration of 4.4µg/ml.

CONCLUSION: Our results demonstrate that both the SEDDS formulations of curcumin have the potential to provide a promising tool for curcumin for its use through topical routes in the treatment of cutaneous and mucocuatenous leishmaniasis.