Magnesium deficiency affects malaria susceptibility in mice.

One hundred twenty mice were fed control and magnesium-(Mg) deficient diets containing 960 and 50 mg Mg/kg, respectively. After 12 days, mice were inoculated with several strains of Plasmodium (P). Parasitemias and survivals were monitored for 20 days after infection. The Mg-deficient diet protected mice against the nonlethal parasite P. chabaudi as shown by decreased parasitemia. All control mice infected with P. vinckei died from the infection. Mg-deficient mice had a much lower parasitemia and recovered from the infection. In mice infected with the lethal strain P. berghei, the parasitemia showed a biphasic response. In control mice, the first phase resulted in the death of 40% of the animals. After a spontaneous reduction of parasitemia, the surviving animals showed a second increase in parasitemia, which resulted in the death of the remaining animals. In the deficient group, all the animals survived the first phase of infection. By contrast, the evolution of the second phase was similar to that observed in controls. Examination of blood smears showed that the second phase corresponded to an invasion of young reticulocytes by the parasite. The results suggest that the protective effect of Mg deficiency is related to the decrease in erythrocyte Mg and to the prooxidative effect of this mineral deficiency in mature erythrocytes.