Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-05T14:07:04.180Z Has data issue: false hasContentIssue false
  • English
  • Français

Megasomes as the targets of leucine methyl ester in Leishmania amazonensis amastigotes

Published online by Cambridge University Press:  06 April 2009

J.-C. Antoine ,
Colette Jouanne  and
Antoinette Ryter
J.-C. Antoine
Affiliation:
Unité d'Immunophysiologie cellulaire de l'Institut Pasteur et du C.N.R.S. (UA 1113), Département de Physiopathologie expérimentale
Colette Jouanne
Affiliation:
Unité d'Immunophysiologie cellulaire de l'Institut Pasteur et du C.N.R.S. (UA 1113), Département de Physiopathologie expérimentale
Antoinette Ryter
Affiliation:
Unité de Microscopie électronique de l'Institut Pasteur et du C.N.R.S. (UA 1148), Département de Biologie moléculaire Institut Pasteur, 25, rue du Dr. Roux, 75724 Paris Cédex 15, France
Get access Rights & Permissions [Opens in a new window]

Summary

Certain L-amino acid esters, such as L-leucine methyl ester (Leu-OMe), can kill intracellular and isolated Leishmania amazonensis amastigotes. Killing appears to involve ester trapping and hydrolysis within an acidified parasite compartment (M. Rabinovitch and S. C. Alfieri, 1987, Brazilian Journal of Medical and Biological Research 20, 665–74). We show here by acid phosphatase light microscopic cytochemistry and by ultrastructural morphometry that megasomes, lysosome-like amastigote organelles, are the putative parasite targets of Leu-OMe. This conclusion is supported by the following observations, (a) Control amastigotes displayed a string of electron-dense, acid phosphatase-positive megasomes mostly located in the cellular poles opposite the flagellar pockets. Incubation of the amastigotes with Leu-OMe resulted in concentration-dependent swelling and fusion of the organelles as well as decreased electron density of the internal contents. These changes, which preceded parasite disruption, were followed by the progressive loss of parasite viability and the release of acid phosphatase activity into the medium, (b) Incubation of the amastigotes with L-isoleucine methyl ester, a non-leishmanicidal compound, induced only moderate fusion of the megasomes. (c) Pre-incubation of the parasites with the proteinase inhibitors antipain and chymostatin, previously shown to confer protection from Leu-OMe toxicity, nearly completely prevented the morphological changes of megasomes. (d) Exposure of amastigotes to tryptophanamide (Trp-NH2), the leishmanicidal activity of which is not reduced by antipain and chymostatin, did not result in swelling and fusion of the megasomes. This last finding suggests that different mechanisms underlie the destruction of amastigotes by Trp-NH2 and Leu-OMe. Overall, the results are compatible with the hypothesis that Leu-OMe and other amino acid esters are trapped and hydrolysed within megasomes.

Keywords

Leishmania amazonensisamastigotemegasomeamino acid ester.
Type
Research Article
Information
Parasitology , Volume 99 , Issue 1 , August 1989 , pp. 1 - 9
Copyright
Copyright © Cambridge University Press 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alexander, J., & Vickerman, K., (1975). Fusion of host cell secondary lysosomes with the parasitophorous vacuoles of Leishmania mexicana — infected macrophages. Journal of Protozoology 22, 502–8.CrossRefGoogle ScholarPubMed
Alfieri, S., Zilberfarb, V., & Rabinovitch, M., (1987). Destruction of Leishmania mexicana amazonensis amastigotes by leucine methyl ester: protection by other amino acid esters. Parasitology 95, 31–41.CrossRefGoogle ScholarPubMed
Alfieri, S., Ramazeilles, C., Zilberfarb, V., Galpin, I., Norman, S. E., & Rabinovitch, M., (1988). Proteinase inhibitors protect Leishmania amazonensis amastigotes from destruction by amino acid esters. Molecular and Biochemical Parasitology 29, 191–201.CrossRefGoogle ScholarPubMed
Anderson, R. G. W., Falck, J. R., Goldstein, J. L., & Brown, M. S., (1984). Visualization of acidic organelles in intact cells by electron microscopy. Proceedings of the National Academy of Sciences, USA 81, 4838–42.CrossRefGoogle ScholarPubMed
Antoine, J. -C., Jouanne, C., Ryter, A., & Benichou, J. -C., (1988). Leishmania amazonensis: acidic organelles in amastigotes. Experimental Parasitology 67, 287–300.Google ScholarPubMed
Barrett, A. J., & Heath, M. F., (1977). Lysosomal enzymes. In Lysosomes: a Laboratory Handbook, (ed. Dingle, J. T.), pp. 19–145. Amsterdam: Elsevier/North Holland Biomedical.Google Scholar
Chang, K. P., (1980). Human cutaneous leishmania in a mouse macrophage line: propagation and isolation of intracellular parasites. Science 209, 1240–2.CrossRefGoogle Scholar
Coombs, G. H., (1982). Proteinases of Leishmania mexicana and other flagellate protozoa. Parasitology 84, 149–55.CrossRefGoogle ScholarPubMed
Coombs, G. H., Tetley, L., Moss, V. A., & Vickerman, K., (1986). Three-dimensional structure of the leishmania amastigote as revealed by computer-aided reconstruction from serial sections. Parasitology 92, 13–23.CrossRefGoogle ScholarPubMed
Decker, R. S., & Fuseler, J. F., (1984). Methylated amino acids and lysosomal function in cultured heart cells. Experimental Cell Research 154, 304–9.CrossRefGoogle ScholarPubMed
Goldman, R., (1976). Ion distribution and membrane permeability in lysosomal suspensions. In Lysosomes in Biology and Pathology, vol. 5, (ed. Dingle, J. T., and Dean, R. T.,), pp. 309–36. Amsterdam: North Holland.Google Scholar
Hassan, H. F., & Coombs, G. H., (1987). Phosphomonoesterases of Leishmania mexicana mexicana and other flagellates. Molecular and Biochemical Parasitology 23, 285–96.CrossRefGoogle ScholarPubMed
Mossmann, T., (1983). Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays. Journal of Immunological Methods 65, 55–63.Google Scholar
Ohkuma, S., & Poole, B., (1981). Cytoplasmic vacuolation of mouse peritoneal macrophages and the uptake into lysosomes of weakly basic substances. Journal of Cell Biology 90, 656–64.CrossRefGoogle ScholarPubMed
Poole, B., & Ohkuma, S., (1981). Effect of weak bases on the intralysosomal pH in mouse peritoneal macrophages. Journal of Cell Biology 90, 665–9.CrossRefGoogle ScholarPubMed
Pupkis, M. F., & Coombs, G. H., (1984). Purification and characterization of proteolytic enzymes of Leishmania mexicana mexicana amastigotes and promastigotes. Journal of General Microbiology 130, 2375–83.Google Scholar
Pupkis, M. F., Tetley, L., & Coombs, G. H., (1986). Leishmania mexicana: amastigote hydrolases in unusual lysosomes Experimental Parasitology 62, 29–39.CrossRefGoogle ScholarPubMed
Rabinovitch, M., & Alfieri, S. C., (1987 a). From lysosomes to cells, from cells to Leishmania: amino acid esters as potential chemotherapeutic agents. Brazilian Journal of Medical and Biological Research 20, 665–74.Google ScholarPubMed
Rabinovitch, M., & Zilberfarb, V., (1988). Destruction of intracellular and isolated Leishmania mexicana amazonensis amastigotes by amino acid amides. Parasitology 96, 289–96.CrossRefGoogle ScholarPubMed
Rabinovitch, M., Zilberfarb, V., & Pouchelet, M., (1987 b). Leishmania mexicana: destruction of isolated amastigotes by amino acid esters. American Journal of Tropical Medicine and Hygiene 36, 288–93.CrossRefGoogle ScholarPubMed
Rabinovitch, M., Zilberfarb, V., & Ramazeilles, C., (1986). Destruction of Leishmania mexicana amazonensis amastigotes within macrophages by lysosomotropic amino acid esters. Journal of Experimental Medicine 163, 520–35.CrossRefGoogle ScholarPubMed
Ramazeilles, C., & Rabinovitch, M., (1989). Leishmania amazonensis: uptake and hydrolysis of 3H amino acid methyl esters by isolated amastigotes. Experimental Parasitology 68, 135–43.Google ScholarPubMed
Reeves, J. P., (1979). Accumulation of amino acids by lysosomes incubated with amino acid methyl esters. Journal of Biological Chemistry 254, 8914–21.CrossRefGoogle ScholarPubMed
Umezawa, H., (1982). Low-molecular weight enzyme inhibitors of microbial origin. Annual Review of Microbiology 36, 75–99.CrossRefGoogle ScholarPubMed
Weibel, E. R., Kistler, G. S., & Scherle, W. F., (1966). Practical stereological methods for morphometric cytology; Journal of Cell Biology 30, 23–38.CrossRefGoogle ScholarPubMed
Wilson, P. D., Firestone, R. A., & Lenard, J., (1987). The role of lysosomal enzymes in killing of mammalian cells by the lysosomotropic detergent N-dodecylimidazole. Journal of Cell Biology 104, 1223–9.CrossRefGoogle ScholarPubMed