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The effect of zinc supplementation on Taenia crassiceps murine cysticercosis was studied in susceptible BALB/cAnN mice. Female offspring of mice supplemented with high zinc throughout gestation and lactation were intraperitoneally infected with T. crassiceps cysticerci. Offspring from nonsupplemented mothers were used as controls. Significantly fewer parasites were recovered from zinc-supplemented mice (Zsm) 30 days after infection. Increased resistance was not related to the IgG antibody response. At early stages of infection, T cells from Zsm proliferated to T. crassiceps antigens, whereas cells from control mice did not respond. Infection caused in both groups a decrease in CD3+ cell percentages, which was more pronounced in the controls, and paralleled by a decrease in CD8+ cells; CD3+ and CD8+ percentages returned to normal levels at later stages of infection. In contrast, the CD4+ subpopulation only decreased in control mice. Intracellular cytokine determinations indicate that zinc supplementation favored a stronger and persistent type-1 T cell response in cysticerci-infected mice, which probably participates in the observed increased resistance.

Oral treatment of zinc modulates cytokine secretion during the gestation, lactation, and weaning periods. We used a experimental mice model of zinc supplementation during the perinatal stages to study the effects of this ion over the production of interleukin IL-1a, 2 IL-12, and tumor necrosis factor-alpha by peritoneal macrophages. In addition, we determined the gene expression of these cytokines. Zinc (500 mg/L) was orally administered to mice from gestation to lactation (6-week treatment, Zn+) and weaning (9-week treatment). The serum cytokines IL-1a and IL-12 were assayed in the offspring at 21 and 42 days after birth. Our results showed a significant (P < 0.01) increase in cytokine production in the Zn+ animals at the end of the lactation stage. There was a tendency for the IL-1 concentration to decrease at postweaning; nevertheless, IL-12 concentrations were increased in mice at 42 days of age (P < 0.001). The production of IL-1a, IL-12, and tumor necrosis factor-alpha in the macrophages supernatants in vitro followed the same tendencies (P < 0.001). Molecular analysis showed an increase of mRNA synthesis in all cases, from 4-fold to 6-fold, in the cytokines analyzed. Our results suggest that the increase in the proinflammatory cytokines as a result of zinc administration may potentiate Th1 cells response, which could lead to the increase of cytokine production in deficient newborns. J. Trace Elem.

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