Nano amphotericin B: a good anti-leishmanial drug with effect on cathelicidin gene expression

Protozoan parasites, such as Leishmania major (L. major), remained as a global health problem of the current century. Leishmania major is a major cause of cutaneous leishmaniasis (CL) in developed and developing countries. Traditionally, amphotericin B is prescribed as an alternative drug, while first-line drugs failed. Some active proteins of the innate immune system such as cathelicidins try to inhibit infection Via several proposed mechanisms. Here this research aimed to not only determine the anti-leishmanial activity of nano amphotericin B but also to evaluate which anti-leishmanial drug can induce the cathelicidin gene expression. Both promastigote and amastigote stages of L. major were exposed to various concentrations of nano amphotericin B, amphotericin B and finally compared to glucan time as standard drug for CL treatment. For the gene expression of cathelicidin, macrophages were exposed to the same concentration of anti-leishmanial drugs. The findings demonstrated that nano amphotericin B was more effective at all concentrations than amphotericin B. Additionally, among tested anti-leishmanial drugs, nano amphotericin B has more potency to induce the cathelicidin gene expression in macrophages cells. The findings revealed that nano amphotericin B has potential as an effective anti-leishmanial drug against CL caused by L. major parasites.

Murine cathelicidin: as a host defensive response against Leishmania major infection

Leishmaniasis is a serious global challenge with neither efficacious prophylactic vaccine nor effective and safe therapeutic measures. Cathelicidins, members of antimicrobial peptides family, are small proteins of innate immunity system, which represent a protective barrier against a number of potential pathogens in living organisms. The murine cathelicidin or cathelin-related antimicrobial peptide (CRAMP) is expressed by a variety of cells or tissues, and highly resembles to human cathelicidin (LL-37). It is naturally expressed at a low concentration in adolescent age, but extensively increases during cutaneous infections. Despite its important role, it has less been investigated in parasitic infections. Among all cells, macrophages and skin cells are the two important cells that directly have a relationship with Leishmania major parasites. The present study aimed to show whether cathelicidins protect their hosts following cutaneous leishmaniasis due to L. major parasites. Both in vitro and in vivo models of L. major infection were established by exposing of J744 cell line (murine macrophages) and BALB/c mice with the stationary phase of L. major promastigotes for 24 h and 7 days. The findings revealed that both macrophages and skin cells significantly (p < 0.05) expressed a high level of CRAMP gene and peptide after challenging with L. major parasites. Thus, our data suggest a protective role for cathelicidins against infections caused by L. major parasites. This experimental model could be considered as a novel potential vaccine candidate for planning future control strategy against human leishmaniasis.