Effect of α-Tocopheryloxy Acetic Acid on the Infection of Mice with Plasmodium berghei ANKA In Vivo and Humans with P. falciparum In Vitro

BackgroundMalarial parasites are susceptible to oxidative stress. The effects of α-tocopheryloxy acetic acid (α-TEA), a vitamin E analog, on infection by Plasmodium berghei ANKA and P. falciparum in mice and human red blood cells (RBCs), respectively, were examined in this study. MethodsFor in vivo studies in mice, RBCs infected with P. berghei ANKA were inoculated via intraperitoneal injection and α-TEA was administered to C57BL/6J male mice after infection. The blood–brain barrier (BBB) permeability was examined by Evans blue staining in experimental cerebral malaria at 7 days after infection. The in vitro inhibitory effect of α-TEA on P. falciparum 3D7 (chloroquine-sensitive strain) and K1 (multidrug-resistant strain) was tested using a SYBR Green I-based assay.ResultsWhen 1.5 % α-TEA was administered for 14 days after infection, 88 % of P. berghei ANKA-infected mice survived during the experimental period. Nevertheless, all the control mice died within 12 days of infection. Furthermore, the Evans blue intensity in α-TEA-treated mice brains was less than that in untreated mice, indicating that α-TEA might inhibit the destruction of the BBB and progression of cerebral malaria. The in vitro experiment revealed that α-TEA inhibited the proliferation of both the 3D7 and K1 strains.ConclusionsThis study showed that α-TEA is effective against murine and human malaria in vivo and in vitro, respectively. Although α-TEA alone has a sufficient antimalarial effect, future research could focus on the combined effect of α-TEA and already existing drugs. The prophylactic antimalarial activity of premedication with α-TEA may also be an interesting perspective in the future.