Skip to main content
NCBI home page
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1985 Dec 1;101(6):2302–2309. doi: 10.1083/jcb.101.6.2302

Antimalarials increase vesicle pH in Plasmodium falciparum

PMCID: PMC2113995  PMID: 3905824

Abstract

The asexual erythrocytic stage of the malarial parasite ingests and degrades the hemoglobin of its host red cell. To study this process, we labeled the cytoplasm of uninfected red cells with fluorescein-dextran, infected those cells with trophozoite- and schizont-rich cultures of Plasmodium falciparum, and harvested them 110-120 h later in the trophozoite stage. After lysis of the red cell cytoplasm with digitonin, the only fluorescence remaining was in small (0.5-0.9 micron) vesicles similar to the parasite's food vacuole. As measured by spectrofluorimetry, the pH of these vesicles was acid (initial pH 5.2- 5.4), and they responded to MgATP with acidification and to weak bases such as NH4Cl with alkalinization. These three properties are similar to those obtained with human fibroblasts and suggest that the endocytic vesicles of plasmodia are similar to those of mammalian cells. Each of the antimalarials tested (chloroquine, quinine, and mefloquine) as well as NH4Cl inhibited parasite growth at concentrations virtually identical to those that increased parasite vesicle pH. These results suggest two conclusions: (a) The increases in vesicle pH that we have observed in our digitonin-treated parasite preparation occur at similar concentrations of weak bases and antimalarials in cultures of parasitized erythrocytes, and (b) P. falciparum parasites are exquisitely dependent on vesicle pH during their asexual erythrocytic cycle, perhaps for processes analogous to endocytosis and proteolysis in mammalian cells, and that antimalarials and NH4Cl may act by interfering with these events.

Full Text

The Full Text of this article is available as a PDF (1.1 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aikawa M. High-resolution autoradiography of malarial parasites treated with 3 H-chloroquine. Am J Pathol. 1972 May;67(2):277–284. [PMC free article] [PubMed] [Google Scholar]
  2. Allison J. L., O'Brien R. L., Hahn F. E. DNA: reaction with chloroquine. Science. 1965 Sep 3;149(3688):1111–1113. doi: 10.1126/science.149.3688.1111. [DOI] [PubMed] [Google Scholar]
  3. Chou A. C., Chevli R., Fitch C. D. Ferriprotoporphyrin IX fulfills the criteria for identification as the chloroquine receptor of malaria parasites. Biochemistry. 1980 Apr 15;19(8):1543–1549. doi: 10.1021/bi00549a600. [DOI] [PubMed] [Google Scholar]
  4. Ciak J., Hahn F. E. Chloroquine: mode of action. Science. 1966 Jan 21;151(3708):347–349. doi: 10.1126/science.151.3708.347. [DOI] [PubMed] [Google Scholar]
  5. Cohen S. N., Yielding K. L. Inhibition of DNA and RNA polymerase reactions by chloroquine. Proc Natl Acad Sci U S A. 1965 Aug;54(2):521–527. doi: 10.1073/pnas.54.2.521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. De Duve C., Wattiaux R. Functions of lysosomes. Annu Rev Physiol. 1966;28:435–492. doi: 10.1146/annurev.ph.28.030166.002251. [DOI] [PubMed] [Google Scholar]
  7. Desjardins R. E., Canfield C. J., Haynes J. D., Chulay J. D. Quantitative assessment of antimalarial activity in vitro by a semiautomated microdilution technique. Antimicrob Agents Chemother. 1979 Dec;16(6):710–718. doi: 10.1128/aac.16.6.710. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. FULTON J. D., RIMINGTON C. The pigment of the malaria parasite Plasmodium berghei. J Gen Microbiol. 1953 Feb;8(1):157–159. doi: 10.1099/00221287-8-1-157. [DOI] [PubMed] [Google Scholar]
  9. Fitch C. D., Chevli R., Banyal H. S., Phillips G., Pfaller M. A., Krogstad D. J. Lysis of Plasmodium falciparum by ferriprotoporphyrin IX and a chloroquine-ferriprotoporphyrin IX complex. Antimicrob Agents Chemother. 1982 May;21(5):819–822. doi: 10.1128/aac.21.5.819. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Fitch C. D. Plasmodium falciparum in owl monkeys: drug resistance and chloroquine binding capacity. Science. 1970 Jul 17;169(3942):289–290. doi: 10.1126/science.169.3942.289. [DOI] [PubMed] [Google Scholar]
  11. Galloway C. J., Dean G. E., Marsh M., Rudnick G., Mellman I. Acidification of macrophage and fibroblast endocytic vesicles in vitro. Proc Natl Acad Sci U S A. 1983 Jun;80(11):3334–3338. doi: 10.1073/pnas.80.11.3334. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Goldstein J. L., Anderson R. G., Brown M. S. Coated pits, coated vesicles, and receptor-mediated endocytosis. Nature. 1979 Jun 21;279(5715):679–685. doi: 10.1038/279679a0. [DOI] [PubMed] [Google Scholar]
  13. Hollemans M., Elferink R. O., De Groot P. G., Strijland A., Tager J. M. Accumulation of weak bases in relation to intralysosomal pH in cultured human skin fibroblasts. Biochim Biophys Acta. 1981 Apr 22;643(1):140–151. doi: 10.1016/0005-2736(81)90226-1. [DOI] [PubMed] [Google Scholar]
  14. Homewood C. A., Warhurst D. C., Peters W., Baggaley V. C. Lysosomes, pH and the anti-malarial action of chloroquine. Nature. 1972 Jan 7;235(5332):50–52. doi: 10.1038/235050a0. [DOI] [PubMed] [Google Scholar]
  15. Jensen J. B. Concentration from continuous culture of erythrocytes infected with trophozoites and schizonts of Plasmodium falciparum. Am J Trop Med Hyg. 1978 Nov;27(6):1274–1276. doi: 10.4269/ajtmh.1978.27.1274. [DOI] [PubMed] [Google Scholar]
  16. LITCHFIELD J. T., Jr, WILCOXON F. A simplified method of evaluating dose-effect experiments. J Pharmacol Exp Ther. 1949 Jun;96(2):99–113. [PubMed] [Google Scholar]
  17. Levy M. R., Siddiqui W. A., Chou S. C. Acid protease activity in Plasmodium falciparum and P. knowlesi and ghosts of their respective host red cells. Nature. 1974 Feb 22;247(5442):546–549. doi: 10.1038/247546a0. [DOI] [PubMed] [Google Scholar]
  18. Lie S. O., Schofield B. Inactivation of lysosomal function in normal cultured human fibroblasts by chloroquine. Biochem Pharmacol. 1973 Dec 1;22(23):3109–3114. doi: 10.1016/0006-2952(73)90197-4. [DOI] [PubMed] [Google Scholar]
  19. Lieber M. R., Steck T. L. A description of the holes in human erythrocyte membrane ghosts. J Biol Chem. 1982 Oct 10;257(19):11651–11659. [PubMed] [Google Scholar]
  20. Merion M., Schlesinger P., Brooks R. M., Moehring J. M., Moehring T. J., Sly W. S. Defective acidification of endosomes in Chinese hamster ovary cell mutants "cross-resistant" to toxins and viruses. Proc Natl Acad Sci U S A. 1983 Sep;80(17):5315–5319. doi: 10.1073/pnas.80.17.5315. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. O'Brien R. L., Olenick J. G., Hahn F. E. Reactions of quinine, chloroquine, and quinacrine with DNA and their effects on the DNA and RNA polymerase reactions. Proc Natl Acad Sci U S A. 1966 Jun;55(6):1511–1517. doi: 10.1073/pnas.55.6.1511. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Ohkuma S., Poole B. Fluorescence probe measurement of the intralysosomal pH in living cells and the perturbation of pH by various agents. Proc Natl Acad Sci U S A. 1978 Jul;75(7):3327–3331. doi: 10.1073/pnas.75.7.3327. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Olson J. A., Kilejian A. Involvement of spectrin and ATP in infection of resealed erythrocyte ghosts by the human malarial parasite, Plasmodium falciparum. J Cell Biol. 1982 Dec;95(3):757–762. doi: 10.1083/jcb.95.3.757. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. PARKER F. S., IRVIN J. L. The interaction of chloroquine with nucleic acids and nucleoproteins. J Biol Chem. 1952 Dec;199(2):897–909. [PubMed] [Google Scholar]
  25. Pfaller M. A., Krogstad D. J. Imidazole and polyene activity against chloroquine-resistant Plasmodium falciparum. J Infect Dis. 1981 Oct;144(4):372–375. doi: 10.1093/infdis/144.4.372. [DOI] [PubMed] [Google Scholar]
  26. Pfaller M. A., Krogstad D. J. Oxygen enhances the antimalarial activity of the imidazoles. Am J Trop Med Hyg. 1983 Jul;32(4):660–665. doi: 10.4269/ajtmh.1983.32.660. [DOI] [PubMed] [Google Scholar]
  27. Polet H., Barr C. F. Chloroquine and dihydroquinine. In vitro studies by their antimalarial effect upon Plasmodium knowlesi. J Pharmacol Exp Ther. 1968 Dec;164(2):380–386. [PubMed] [Google Scholar]
  28. Poole B., Ohkuma S. Effect of weak bases on the intralysosomal pH in mouse peritoneal macrophages. J Cell Biol. 1981 Sep;90(3):665–669. doi: 10.1083/jcb.90.3.665. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Pressman B. C., Harris E. J., Jagger W. S., Johnson J. H. Antibiotic-mediated transport of alkali ions across lipid barriers. Proc Natl Acad Sci U S A. 1967 Nov;58(5):1949–1956. doi: 10.1073/pnas.58.5.1949. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Roos A., Boron W. F. Intracellular pH. Physiol Rev. 1981 Apr;61(2):296–434. doi: 10.1152/physrev.1981.61.2.296. [DOI] [PubMed] [Google Scholar]
  31. Sly W. S., Fischer H. D. The phosphomannosyl recognition system for intracellular and intercellular transport of lysosomal enzymes. J Cell Biochem. 1982;18(1):67–85. doi: 10.1002/jcb.1982.240180107. [DOI] [PubMed] [Google Scholar]
  32. Stahl P., Schlesinger P. H., Sigardson E., Rodman J. S., Lee Y. C. Receptor-mediated pinocytosis of mannose glycoconjugates by macrophages: characterization and evidence for receptor recycling. Cell. 1980 Jan;19(1):207–215. doi: 10.1016/0092-8674(80)90402-x. [DOI] [PubMed] [Google Scholar]
  33. Steinman R. M., Mellman I. S., Muller W. A., Cohn Z. A. Endocytosis and the recycling of plasma membrane. J Cell Biol. 1983 Jan;96(1):1–27. doi: 10.1083/jcb.96.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Trager W., Brohn F. H. Coezyme A requirement of malaria parasites: effects of coenzyme A precursors on extracellular development in vitro of Plasmodium lophurae. Proc Natl Acad Sci U S A. 1975 May;72(5):1834–1837. doi: 10.1073/pnas.72.5.1834. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Trager W., Jensen J. B. Human malaria parasites in continuous culture. Science. 1976 Aug 20;193(4254):673–675. doi: 10.1126/science.781840. [DOI] [PubMed] [Google Scholar]
  36. Wibo M., Poole B. Protein degradation in cultured cells. II. The uptake of chloroquine by rat fibroblasts and the inhibition of cellular protein degradation and cathepsin B1. J Cell Biol. 1974 Nov;63(2 Pt 1):430–440. doi: 10.1083/jcb.63.2.430. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Yayon A., Cabantchik Z. I., Ginsburg H. Identification of the acidic compartment of Plasmodium falciparum-infected human erythrocytes as the target of the antimalarial drug chloroquine. EMBO J. 1984 Nov;3(11):2695–2700. doi: 10.1002/j.1460-2075.1984.tb02195.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Yayon A., Cabantchik Z. I., Ginsburg H. Susceptibility of human malaria parasites to chloroquine is pH dependent. Proc Natl Acad Sci U S A. 1985 May;82(9):2784–2788. doi: 10.1073/pnas.82.9.2784. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Yayon A., Vande Waa J. A., Yayon M., Geary T. G., Jensen J. B. Stage-dependent effects of chloroquine on Plasmodium falciparum in vitro. J Protozool. 1983 Nov;30(4):642–647. doi: 10.1111/j.1550-7408.1983.tb05336.x. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES