Linked Life Data

3412375

Source:http://linkedlifedata.com/resource/pubmed/id/3412375

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1988-10-6
pubmed:abstractText
Lysosomotropic amino acid esters and amides kill Leishmania amazonensis amastigotes by a mechanism which probably involves enzymatic hydrolysis of the compounds and rapid accumulation of less permeant amino acid within the parasites. We show here that, in agreement with this model, the proteinase inhibitors antipain and chymostatin prevented the killing of intracellular and isolated parasites by L-leucine methyl ester (Leu-OMe). Survival of Leishmania within macrophages was assessed microscopically, and that of isolated amastigotes was measured by tetrazolium (MTT) reduction. Near maximal protection of intracellular parasites was obtained after 24 h incubation of macrophage cultures with 50 micrograms ml-1 antipain or chymostatin. Incubation for greater than 1 h with chymostatin or greater than 4 h with antipain alone resulted in loss of viability of the parasites. Protective activity was only slightly diminished by 20 h chase of isolated parasites in inhibitor-free medium. Two synthetic chymostatin analogues, Z-Val-Phe-Sc and Z-Ile-Phe-Sc, protected isolated amastigotes at 4 or 10 micrograms ml-1. With the exception of Trp-NH2, the toxicity of which was only minimally inhibited, antipain and chymostatin also prevented parasite destruction by other amino acid derivatives. Finally, in concentration-dependent fashion, the inhibitors reduced the accumulation of [3H]leucine in isolated amastigotes incubated with [3H]Leu-OMe. Since uptake of labelled ester was unaffected, we postulate that protection involves inhibition of the parasite enzymes which hydrolyse the amino acid derivatives.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
191-201
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Proteinase inhibitors protect Leishmania amazonensis amastigotes from destruction by amino acid esters.
pubmed:affiliation
Institut Pasteur, Paris, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't