Premium
Inhibition of ecto‐ATPase activity by CrATP interferes in the promastigote‐macrophage interaction in Leishmania amazonensis infection
Author(s) -
Moreira Otacilio da Cruz,
Vidal Vitor Ennes,
d'ÁvilaLevy Claudia Masini,
Britto Constança,
Barrabin Hector
Publication year - 2011
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.25.1_supplement.966.3
Subject(s) - internalization , leishmania , biology , endocytic cycle , nucleoside triphosphate , amastigote , infectivity , macrophage , virulence , atpase , microbiology and biotechnology , in vitro , biochemistry , endocytosis , enzyme , immunology , cell , nucleotide , parasite hosting , virus , world wide web , computer science , gene
Recent works have shown the relationship between Ecto‐Nucleoside‐Triphosphate‐Diphosphohydrolases (Ecto‐NTPDases) and virulence and infectivity in trypanosomatids. We characterized the inhibition of the ecto‐ATPase activity and promastigote growth of Leishmania amazonensis by CrATP. Furthermore, we used this compound to investigate the role of ecto‐NTPDase in the adhesion and internalization of L. amazonensis in resident peritoneal macrophages from BALB/C mice. CrATP partially inhibits the ecto‐ATPase activity of ecto‐NTPDase, presenting Ki= 575.7±199.1 and 383.5±79.0 μM, in the presence or absence of 5 mM MgCl 2 , respectively. The apparent Km for ATP (2.9±0.5 mM) is not altered by CrATP, suggesting a reversible non‐competitive inhibition. When CrATP was added to the cultivation medium at 500 μM, it drastically inhibited the cellular growth after 72 h. The interaction of promastigote forms of L. amazonensis with macrophages is strongly affected by CrATP. When the parasites are pre‐treated with 500 μM CrATP before interacting with macrophages, the adhesion and endocytic index are strongly reduced to 53.0±14.8% and 39.8±1.1%, respectively. These results indicate that ecto‐NTPDase plays an important role in the infection process caused by L. amazonensis and that CrATP is a potential prototype for Leishmaniasis chemotherapy.