Photoactivity of ultradeformable liposome of Aluminium phthalocyanine chloride on promastigotes of Leishmania chagasi and THP-1 macrophages

INDIRA HERNANDEZ; EDER ROMERO; WILFREDO VALDIVIESO; JORGE MONTANARI; MARÍA JOSÉ MORILLA; FERNANDO MARTINEZ; EDGAR PAEZ; PATRICIA ESCOBAR

Lucknow, India

Congreso; WorldLeish 4, 4th World Congress on Leishmaniasis; 2009

Introduction The liposomes ultradeformables (UDL) are vehicles used for drugs transport of topical application. The use of photodynamic therapy against cutaneous leishmaniasis using phthalocyanine aluminium chloride (AlPcCl) is a promissory alternative and the incorporation of this photosensitizer in UDL could increase their activity and improve their specificity. In this work we reported the phototoxic activity of liposomes ultradeformables of AlPcC (UDL-AlPcCl) on promastigotes of Leishmania chagasi and THP-1 cells. Materials and Methods Promastigotes and intracellular amastigotes of L. chagasi and THP-1 cells treated with AlPcCl-free, UDL-AlPcCl (1.66-0.0000282 μM) and UDL-empty (0402-0, 000061 μg/mL phospholipids) were irradiated at 597-752nm at a fluence of 17 J/cm2. Control cells were kept in darkness. Promastigote inhibition was determined by counting parasite numbers in a Neubauer haemocytometer and intracellular amastigotes by percent of infected cells in treated and untreated cultures in Giemsa stained slides. The results were expressed in inhibitory concentration 50 (IC50) and cytotoxic concentration 50 (CC50) values were calculated by sigmoidal regression analysis. Results UDL-AlPcCl was highly phototoxic in promastigotes of L. chagasi (IC50 of 3.77 E-05 μM) and was 91 times more active than AlPcCl-free (IC50 0.0034 μM). Intracellular amastigotes showed IC50 0.04 µM and 0.00068 µM on AlPcCl-free and UDL-AlPcCl respectively. In THP-1 cells, UDL- PcAlCl phototoxic activity was CC50 0.00070627 μM and using PcAlCl-free was 0.0037 μM. In darkness, UDL-PcAlCl and UDL-empty were toxic on promastigotes but not in THP-1 cells. Conclusions The incorporation of PcAlCl on liposome ultradeformables increase phothodynamic effect in vitro against the parasite. In vivo studies are required to confirm the activity of UDL-PcAlCl and its potential application in the treatment of cutaneous leishmaniasis. Acknowledgments This work was supported by the Instituto Colombiano para el Desarrollo de la Ciencia y la Tecnologia “Francisco Jose de Caldas” COLCIENCIAS (Grant 1102-04-14130) and by the Universidad Industrial de Santander