The Effect of Alkanna tincturia and Peganum harmala Extracts on Leishmania major (MRHO/IR/75/ER) in vitro

Abstract

Background: Cutaneous leishmaniasis is an important health problem caused by Leishmania spp. As there is no vaccine, drug treatment is the only way to tackle leishmaniasis. In the present study, inhibitory and kill­ing effects of Peganum harmala and Alkana tinctoria extracts on amastigotes and promastigotes forms of Leishmania were evaluated in-vitro.
Methods: The seeds of Peganum harmala, Stems and roots of Alkanna tictoria were collected and crude extrac­tion carried out. In this experimental study,  Leishmania major promastigotes were cultured in RPMI-1640 with 10% FBS at 22-26°C, and infected macrophages with amastigotes   were cultured in RPMI-1640 with 10% FBS at 37°C in 5% CO2. Then the extracts of each plant were added to cultivated parasites and incubated for 3 days. Promastigote and amastigote assay was carried out using   counting assay based on growth inhibition.
Results: The results indicated that both extractions can inhibit the growth of promastigotes, and in concentra­tions of 40µg/ml of P. harmala , 200µg/ml of A. tincturia, and 20 µg/ml of equal combination of P. hamala and A. tincturia are Inhibitory Concentration (IC₅₀) for parasites growth. By adding these concentra­tions of the extracts to the infected macrophages in the culture, their effects were separately eva­lu­ated. The mean of amastigotes number in macrophages in the culture with P. harmala, A. ticturia, combina­tion and control groups were 0.7, 0.7, 0.6, 2.3 amastigotes per macrophage, respectively.
Conclusion: By this method, inhibition of intracellular and extracellular growth of L. major was demon­strated suggesting that, plant drugs with efficacy and safe products can be applied as new treatment for cutane­ous leishmaniasis.