Skip to main content
Antimicrobial Agents and Chemotherapy logoLink to Antimicrobial Agents and Chemotherapy
. 1990 Jul;34(7):1371–1375. doi: 10.1128/aac.34.7.1371

Antimalarial activity of a combination of 5-fluoroorotate and uridine in mice.

Z M Gómez 1, P K Rathod 1
PMCID: PMC175983  PMID: 2386369

Abstract

Malarial parasites, in contrast to mammalian cells, utilize orotic acid more efficiently than uracil or uridine. Recently, chloroquine-susceptible and chloroquine-resistant clones of Plasmodium falciparum were shown to be inhibited by 5-fluoroorotate, with a 50% inhibitory concentration of 6 nM in vitro. Mammalian cells were far less sensitive to 5-fluoroorotate, particularly in the presence of uridine. In this report, the antimalarial activity of 5-fluoroorotate was tested in vivo. Initially, levels of 5-fluoroorotate in plasma were determined in Swiss mice injected intraperitoneally with radioactive 5-fluoroorotate. On the basis of the pharmacokinetics profile, mice infected with Plasmodium yoelii were treated with 5-fluoroorotate at a dose of 0.2 or 5 mg/kg (body weight) every 4 h for 3 days. At the nontoxic dose of 0.2 mg/kg, the reduction in parasitemia was followed by a temporary resurgence of parasitemia. This second wave of parasitemia cleared without additional 5-fluoroorotate treatment. To radically eliminate P. yoelii from mice and avoid the second wave of parasitemia, a higher dose of 5 mg of 5-fluoroorotate per kg had to be used. In the absence of uridine, repeated doses of 5 mg/kg were toxic to mice, as judged by weight loss, diarrhea, decreased numbers of leukocytes, and increased mortality. However, in the presence of uridine, repeated doses of 5 mg/kg could be used for antimalarial chemotherapy without obvious toxicity. Mice cured with 5-fluoroorotate and uridine were immune to subsequent challenge with a potentially lethal inoculum of P. yoelii.

Full text

PDF
1371

Selected References

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

  1. BOSCH L., HARBERS E., HEIDELBERGER C. Studies on fluorinated pyrimidines. V. Effects on nucleic acid metabolism in vitro. Cancer Res. 1958 Apr;18(3):335–343. [PubMed] [Google Scholar]
  2. CHAUDHURI N. K., MONTAG B. J., HEIDELBERGER C. Studies on fluorinated pyrimidines. III. The metabolism of 5-fluorouracil-2-C14 and 5-fluoroorotic-2-C14 acid in vivo. Cancer Res. 1958 Apr;18(3):318–328. [PubMed] [Google Scholar]
  3. Gutteridge W. E., Trigg P. I. Incorporation of radioactive precursors into DNA and RNA of Plasmodium knowlesi in vitro. J Protozool. 1970 Feb;17(1):89–96. doi: 10.1111/j.1550-7408.1970.tb05163.x. [DOI] [PubMed] [Google Scholar]
  4. HEIDELBERGER C., GRIESBACH L., MONTAG B. J., MOOREN D., CRUZ O., SCHNITZER R. J., GRUNBERG E. Studies on fluorinated pyrimidines. II. Effects on transplanted tumors. Cancer Res. 1958 Apr;18(3):305–317. [PubMed] [Google Scholar]
  5. Houghton J. A., Houghton P. J., Wooten R. S. Mechanism of induction of gastrointestinal toxicity in the mouse by 5-fluorouracil, 5-fluorouridine, and 5-fluoro-2'-deoxyuridine. Cancer Res. 1979 Jul;39(7 Pt 1):2406–2413. [PubMed] [Google Scholar]
  6. Jones M. E. Pyrimidine nucleotide biosynthesis in animals: genes, enzymes, and regulation of UMP biosynthesis. Annu Rev Biochem. 1980;49:253–279. doi: 10.1146/annurev.bi.49.070180.001345. [DOI] [PubMed] [Google Scholar]
  7. Leyva A., van Groeningen C. J., Kraal I., Gall H., Peters G. J., Lankelma J., Pinedo H. M. Phase I and pharmacokinetic studies of high-dose uridine intended for rescue from 5-fluorouracil toxicity. Cancer Res. 1984 Dec;44(12 Pt 1):5928–5933. [PubMed] [Google Scholar]
  8. Martin D. S., Stolfi R. L., Sawyer R. C., Spiegelman S., Young C. W. High-dose 5-fluorouracil with delayed uridine "rescue" in mice. Cancer Res. 1982 Oct;42(10):3964–3970. [PubMed] [Google Scholar]
  9. McCormick G. J., Canfield C. J., Willet G. P. In vitro antimalarial activity of nucleic acid precursor analogues in the simian malaria Plasmodium knowlesi. Antimicrob Agents Chemother. 1974 Jul;6(1):16–21. doi: 10.1128/aac.6.1.16. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Moyer J. D., Malinowski N., Ayers O. Salvage of circulating pyrimidine nucleosides by tissues of the mouse. J Biol Chem. 1985 Mar 10;260(5):2812–2818. [PubMed] [Google Scholar]
  11. Payne D. Spread of chloroquine resistance in Plasmodium falciparum. Parasitol Today. 1987 Aug;3(8):241–246. doi: 10.1016/0169-4758(87)90147-5. [DOI] [PubMed] [Google Scholar]
  12. Rathod P. K., Khatri A., Hubbert T., Milhous W. K. Selective activity of 5-fluoroorotic acid against Plasmodium falciparum in vitro. Antimicrob Agents Chemother. 1989 Jul;33(7):1090–1094. doi: 10.1128/aac.33.7.1090. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Sherman I. W. Biochemistry of Plasmodium (malarial parasites). Microbiol Rev. 1979 Dec;43(4):453–495. doi: 10.1128/mr.43.4.453-495.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Weber G., Shiotani T., Kizaki H., Tzeng D., Williams J. C., Gladstone N. Biochemical strategy of the genome as expressed in regulation of pyrimidine metabolism. Adv Enzyme Regul. 1977 Oct 3;16:3–19. doi: 10.1016/0065-2571(78)90064-x. [DOI] [PubMed] [Google Scholar]

Articles from Antimicrobial Agents and Chemotherapy are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES