Ellagic acid microspheres restrict the growth of Babesia and Theileria in vitro and Babesia microti in vivo

Abstract

Background There are no effective vaccines against Babesia and Theileria parasites; therefore, therapy depends heavily on antiprotozoal drugs. Treatment options for piroplasmosis are limited; thus, the need for new antiprotozoal agents is becoming increasingly urgent. Ellagic acid (EA) is a polyphenol found in various plant products and has antioxidant, antibacterial and effective antimalarial activity in vitro and in vivo without toxicity. The present study documents the efficacy of EA and EA-loaded nanoparticles (EA-NPs) on the growth of Babesia and Theileria . Methods In this study, the inhibitory effect of EA, β-cyclodextrin ellagic acid (β-CD EA) and antisolvent precipitation with a syringe pump prepared ellagic acid (APSP EA) was evaluated on four Babesia species and Theileria equi in vitro , and on the multiplication of B. microti in mice. The cytotoxicity assay was tested on Madin-Darby bovine kidney (MDBK), mouse embryonic fibroblast (NIH/3T3) and human foreskin fibroblast (HFF) cell lines. Results The half-maximal inhibitory concentration (IC 50 ) values of EA and β-CD EA on B. bovis , B. bigemina , B. divergens , B. caballi and T. equi were 9.58 ± 1.47, 7.87 ± 5.8, 5.41 ± 2.8, 3.29 ± 0.42 and 7.46 ± 0.6 µM and 8.8 ± 0.53, 18.9 ± 0.025, 11 ± 0.37, 4.4 ± 0.6 and 9.1 ± 1.72 µM, respectively. The IC 50 values of APSP EA on B. bovis , B. bigemina , B. divergens , B. caballi and T. equi were 4.2 ± 0.42, 9.6 ± 0.6, 2.6 ± 1.47, 0.92 ± 5.8 and 7.3 ± 0.54 µM, respectively. A toxicity assay showed that EA, β-CD EA and APSP EA affected the viability of cells with a half-maximal effective concentration (EC 50 ) higher than 800 µM. In the experiments on mice, APSP EA at a concentration of 70 mg/kg reduced the peak parasitemia of B . microti by 68.1%. Furthermore, the APSP EA-atovaquone (AQ) combination showed a higher chemotherapeutic effect than that of APSP EA monotherapy. Conclusions To our knowledge, this is the first study to demonstrate the in vitro and in vivo antibabesial action of EA-NPs and thus supports the use of nanoparticles as an alternative antiparasitic agent. Electronic supplementary material The online version of this article (10.1186/s13071-019-3520-x) contains supplementary ma...

Phytochemical Screening and Antiprotozoal Effects of the Methanolic Berberis Vulgaris and Acetonic Rhus Coriaria Extracts

“…For conducting in vitro experiments, B. bigemina Argentine strain [49], B. divergens Germany strain, Texas strain B. bovis were cultured in cattleRBCs, whereas United States Department of Agriculture (USDA) strains B. caballi and T. equi were maintained in horse RBCs; for conducting in vivo study, eight-week-old female BALB/c mice weighing 25 grams (g) were obtained from CLEA Japan and infected with rodent-borne parasitic nonzoonotic agent, B. microti Munich strain (AB071177) [49][50][51].…”

“…The hemolytic efficacy of MEBV and AERC on cattle and horse RBCs was evaluated in vitro as previously reported elsewhere [51]. Initially, MEBV and AERC at a concentration of 300 µg/mL were cultivated at 37 • C with purified bovine and equine RBCs for 3 h. Afterward, the pretreated-RBCs were added to T. equiand B. bovis-iRBCs after washing thrice with phosphate-buffered saline (PBS) to achieve 1% parasitemia.…”

“…The cell viability test was conducted in a 96-well plate as described elsewhere [4,9,51,52]. Briefly, an aliquot of (100 µL) cells was implanted at a concentration of 5 × 10 4 cells/mL in DMEM or MEM with fetal bovine serum and incubated overnight under atmosphere 5% CO 2 at 37 • C for attachment.…”

“…MEBV and AERC were examined for their in vivo chemotherapeutic efficacy using B. microti-infected BALB/c mice according to a procedure described elsewhere [49,51]. Briefly, twenty-five mice were placed in an environment free from pathogens with 22 • C temperature and adjusted humidity and under 12 h light and 12 h darkness and randomly distributed into five groups.…”

Formulation Strategies to Improve Oral Bioavailability of Ellagic Acid

“…In another study, Beshbishy et al obtained m-EA using the anti-solvent precipitation method by injecting into deionized water a 10 mg/mL ethanolic solution of EA at a fixed flow rate [53]. m-EA particles, collected by filtration and vacuum dried, showed modified morphology with respect to the parent material and appeared as needle-shaped or rod-like structures.…”