Abstract:
:Parasites of the Leishmania genus require for the growth and viability the de novo synthesis of specific sterols as such as episterol and 5-dehydroepisterol because cholesterol, which is abundant in their mammalian hosts, does not fulfill the parasite sterol requirements. Squalene synthase catalyzes the first committed step in the sterol biosynthesis and has been studied as a possible target for the treatment of high cholesterol levels in humans. In this work we investigated the antiproliferative and ultrastructural effects induced by 3-(biphenyl-4-yl)-3-hydroxyquinuclidine (BPQ-OH), a specific inhibitor of squalene synthase, on promastigote and amastigote forms of Leishmania amazonensis. BPQ-OH had a potent dose-dependent growth inhibitory effect against promastigotes and amastigotes, with IC(50) values 0.85 and 0.11 microM, respectively. Ultrastructural analysis of the treated parasites revealed several changes in the morphology of promastigote forms. The main ultrastructural change was found in the plasma membrane, which showed signs of disorganization, with the concomitant formation of elaborated structures. We also observed alterations in the mitochondrion-kinetoplast complex such as mitochondrial swelling, rupture of its internal membrane and an abnormal compaction of the kinetoplast. Other alterations included the appearance of multivesicular bodies, myelin-like figures, alterations of the flagellar membrane and presence of parasites with two or more nuclei and kinetoplasts. We conclude that the BPQ-OH was a potent growth inhibitor of L. amazonensis, which led to profound changes of the parasite's ultrastructure and might be a valuable lead compound for the development of novel anti-Leishmania agents.
journal_name
Exp Parasitoljournal_title
Experimental parasitologyauthors
Rodrigues JC,Urbina JA,de Souza Wdoi
10.1016/j.exppara.2005.08.006keywords:
subject
Has Abstractpub_date
2005-12-01 00:00:00pages
230-8issue
4eissn
0014-4894issn
1090-2449pii
S0014-4894(05)00208-0journal_volume
111pub_type
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journal_title:Experimental parasitology
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pub_type: 杂志文章
doi:10.1016/j.exppara.2013.02.015
更新日期:2013-05-01 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
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pub_type: 杂志文章
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