Interaction of apigenin-7-O-glucoside with pyrimethamine against Toxoplasma gondii growth

Daniel A. Abugri, William H. Witola

Research output: Contribution to journalArticlepeer-review


Apigenin-7-O-glucoside, a flavonoid glucoside known to inhibit cancer cell growth, fungi growth, both intra and extracellular reactive oxygen species generation, causing cell arrest and damage to the plasma membrane, was tested alone or in combination with a dihydrofolate inhibitor (pyrimethamine) against Toxoplasma gondii (T. gondii) growth. The anti-T. gondii activity was carried out using a high throughput antiparasitic drug screening cell-based assay known as 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium, monosodium salt (WST-8) and fluorescence plate reader. The 50% effective concentration inhibition and 95% confidence interval values for individual and combination treatments against T. gondii were 0.80 (0.38–1.29) µg/mL, 1.05 (0.275–2.029) µg/mL, and 0.40 (0–1.06) µg/mL for apigenin-7-O-glucoside, pyrimethamine, and apigenin-7-O-glucoside plus pyrimethamine, respectively. Interestingly, the apigenin-7-O-glucoside plus pyrimethamine combination showed an additive inhibition effect against T. gondii growth in vitro using the fractional inhibitory concentration index method. It was discovered that the apigenin-7-O-glucoside combination with pyrimethamine had a high selectivity index 62.5, which implies 62-fold inhibition activity against the parasite versus human foreskin fibroblast cell cytotoxicity. This new combination hit is novel and will have the potential for future effective, safe, and less costly anti-Toxoplasma drug development, if its in vivo activity shows similar findings.

Original languageEnglish (US)
Pages (from-to)221-229
Number of pages9
JournalJournal of Parasitic Diseases
Issue number1
StatePublished - Mar 1 2020


  • Anti-toxoplasmosis
  • Drug combination
  • Flavonoid glucoside
  • Pyrimethamine

ASJC Scopus subject areas

  • Parasitology


Dive into the research topics of 'Interaction of apigenin-7-O-glucoside with pyrimethamine against Toxoplasma gondii growth'. Together they form a unique fingerprint.

Cite this