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Exp Parasitol 2000 Mar;94(3):198-200
Aminothiol multidentate chelators against Chagas disease.
Deharo E, Loyevsky M, John C, Balanza E, Ruiz G, Munoz V, Gordeuk VR
Institut de Recherche pour le Developpement (IRD), La Paz, CP 9214,
Bolivia. plantibba@megalink.com
Three compounds of an aminothiol family of iron chelators were
examined for activity against trypomastigote (human) and epimastigote
(vector) forms of Trypanosoma cruzi: tetraethyl and tetramethyl
derivatives of ethane-1,2-bis (N-1-amino-3-ethyl butyl-3-thiol)
(BAT-TE and BAT-TM) and N',N',N'-tris-(2-methyl-2-mercaptopriopyl)-
1,4,7-triazacyclonane (TAT). BAT-TE at 270 microM completely arrested
the growth of trypomastigote forms in mouse blood stored at 4 degrees
C for 24 h (IC(50) 67.7+/-7 microM), while BAT-TM arrested growth at
630 microM (IC(50) 158+/-17 microM) and TAT at concentrations >800
microM (IC(50) 415+/-55 microM). In T. cruzi-infected mice, BAT-TE and
BAT-TM had no anti-trypanosomal activity in doses up to 200 mg/kg,
whether the route of administration was intraperitoneal or oral, and
TAT was not tested due to insufficient quantity. TAT had an IC(50) of
52+/-7 microM against the epimastigote forms while BAT-TM and BAT-TE
were inhibitory only at concentrations >250 microM. The trypanocidal
activity of BAT derivatives in blood stored at 4 degrees C makes these
compounds potential candidates for the purpose of clearing donated
blood of trypomastigotes. Copyright 2000 Academic Press.
PMID: 10831386, UI: 20293541
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J Inorg Biochem 1995 Dec;60(4):277-88
Chelating agent inhibition of Trypanosoma cruzi epimastigotes in vitro.
Rodrigues RR, Lane JE, Carter CE, Bogitsh BJ, Singh PK, Zimmerman LJ,
Molenda JJ, Jones MM
Department of Biology, Vanderbilt University, Nashville, Tennessee
37235, USA.
A number of chelating agents and some of their derivatives are as
effective as, or superior to, benznidazole, the compound currently in
clinical use, in the suppression of the reproduction of epimastigotes
of Trypanosoma cruzi, the protozoa that causes Chagas' disease. All
compounds were examined at a culture concentration of 5 micrograms/mL.
The most effective compounds included
N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine, sodium
diethylamine-N-carbodithioate, piperidine-N-carbodithioate and several
of its analogs, a number of other carbodithioates with two nonpolar
groups on the nitrogen, and tetraethylthiuram disulfide, a prodrug of
sodium diethylamine-N-carbodithioate and widely used in the treatment
of alcoholism. The introduction of additional ionic or nonionic polar
groups on the chelating molecule generally results in a loss of
tyrpanocidal activity. Common commercially available chelating agents
which exhibited no activity included D-penicillamine,
meso-2,3-dimercaptosuccinic acid, and triethylenetetramine
tetrahydrochloride. Dose-response data on the culture indicated that
some of these compounds exhibited inhibition of Trypanosoma cruzi
epimastigotes at concentrations as low as 0.625 microgram/mL. It is
proposed that the mechanism of action of these compounds is based on
their ability to interfere with the essential metal metabolism at
intracellular sites of the epimastigote involving iron, copper, or
zinc. The results also indicate that a certain degree of
hydrophobicity may be necessary for the groups attached to the literal
metal-bonding structure if the compounds are to successfully inhibit
the epimastigotes of Trypanosoma cruzi. The development of
antiprotozoal drugs which are chelating agents specifically designed
to selectively disrupt the essential metal metabolism of Trypanosoma
cruzi should furnish a new generation of drugs which can be used in
the treatment of Chagas' disease.
PMID: 8530923, UI: 96081476
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Comp Biochem Physiol Comp Physiol 1993 Dec;106(4):813-21
The effect of iron nutritional status on Trypanosoma cruzi infection in
germfree and conventional mice.
Pedrosa ML, Nicoli JR, Silva ME, Silva ME, Silva ME, Vieira LQ, Bambirra
EA, Vieira EC
Departamento de Ciencias Biologicas, Universidade Federal de Ouro
Preto, MG, Brazil.
1. Conventional (CV) and gnotobiotic (GN) female CFW mice were
infected with the Y strain of Trypanosoma cruzi. 2. After infection,
both CV and GN groups received injections of iron-dextran or
desferrioxamine. Non-injected mice served as controls. 3. The
parasitemia was more intense in iron-dextran-treated mice. 4. The iron
levels in serum, liver, and spleen were: (a) not decreased by
desferrioxamine and (b) increased by iron-dextran treatments. 5. An
increase in leukocyte numbers was observed in all GN and CV groups
after infection. 6. There was no difference in total iron binding
capacity (TIBC) and iron saturation transferrin (IST) between GN and
CV mice before infection. 7. In CV groups, after infection, TIBC was
decreased whereas the levels of IST were increased; in GN the opposite
occurred. 8. Trypanosome-specific IgG and IgM antibody levels were
raised in the GN group but not in the CV group.
PMID: 7906641, UI: 94155566
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