Department of Parasitology, Institute of Tropical Medicine "Pedro Kourí", Havana City, Cuba.
Pharm Biol. 2010 Sep;48(9):1053-8. doi: 10.3109/13880200903485729.
Leishmaniasis is a widespread tropical infection caused by different species of Leishmania protozoa. There is no immunoprophylaxis (vaccination) available for Leishmania infections and conventional treatments are unsatisfactory; therefore antileishmanial drugs are urgently needed. Natural products are attractive due to their structural diversity.
The present work investigated the antileishmanial action of 21 species of plants.
Plants were collected and their hydroalcoholic extracts were screened against promastigotes and amastigotes of L. amazonensis. Their toxicity was also assayed against peritoneal macrophages from BALB/c mice.
Five extracts showed significant growth inhibitory activity against promastigote form. Only the extracts from Bidens pilosa L. (Asteraceae) and Punica granatum L. (Punicaceae) inhibited the growth of intracellular amastigotes, with IC(50) values of 42.6 and 69.6 microg/mL, respectively. In addition, a low toxicity on macrophage from BALB/c mice was observed.
The antiparasitic activities of B. pilosa and P. granatum have been reported against other parasitic agents and their actions can be the results of flavonoids present in the extracts.
This study supports the importance of natural products as potential sources in the search for new antileishmanial drugs.
利什曼病是一种由不同种利什曼原虫引起的广泛流行的热带感染。目前尚无针对利什曼原虫感染的免疫预防措施（疫苗接种），常规治疗也不尽如人意；因此，急需抗利什曼病药物。天然产物因其结构多样性而具有吸引力。
本研究调查了 21 种植物的抗利什曼作用。
收集植物并对其水醇提取物进行筛选，以检测其对 L. amazonensis 前鞭毛体和无鞭毛体的抑制作用。还对来自 BALB/c 小鼠的腹腔巨噬细胞进行了毒性测定。
五种提取物对前鞭毛体形式的生长具有显著的抑制活性。只有来自 Bidens pilosa L.（菊科）和 Punica granatum L.（石榴科）的提取物抑制了细胞内无鞭毛体的生长，IC50 值分别为 42.6 和 69.6 μg/mL。此外，对来自 BALB/c 小鼠的巨噬细胞的毒性较低。
B. pilosa 和 P. granatum 的抗寄生虫活性已被报道针对其他寄生虫，其作用可能是提取物中存在的类黄酮所致。
本研究支持天然产物作为寻找新的抗利什曼病药物的潜在来源的重要性。
