title: Changes in serum zinc levels associated with giardiasis and dietary zinc intake in mice.
abstract: The association of giardiasis with the malabsorption of zinc remains controversial. This study investigated changes in serum zinc levels in Giardia-infected mice subjected to different dietary zinc regimens. Thirty-five mice (strain C(3)H/H(e)J) were randomly categorized into two groups. The first group was inoculated with 5 × 10(6) Giardia trophozoites (n = 18), and the second group remained Giardia free (n = 17). Each group (Giardia infected and Giardia free) was randomly classified into three subgroups and given low (9 mg Zn/kg), normal (33 mg Zn/kg), and high levels (288 mg Zn/kg) of dietary zinc over a 2-week period for acclimation. Fourteen days post-Giardia infection, all of the mice were euthanized and blood samples were collected. The number of trophozoites was quantified (hematocytometer), and serum zinc levels were determined via atomic absorption spectrophotometry. Significant increases in the median weights were only found in the Giardia-free mice (p < 0.05). A higher final median weight was found in the Giardia-free group when compared with that of the Giardia-infected group given low dietary zinc (p = 0.013). In the Giardia-infected group with low dietary zinc, the geometric mean of trophozoites was 3,498 ± 101 (SE) per milliliter. The Giardia-infected group had lower serum zinc levels than did the Giardia-free group with the high dietary zinc regimens (p < 0.05). Our results are consistent with studies among human populations, but further studies are required to elucidate the actual mechanism governing the zinc-giardiasis interaction.
authors.affiliation: Department of Public Nutrition and Health, Coordination of Nutrition, Centro de Investigación en Alimentación y Desarrollo, A.C. Carretera al Ejido La Victoria Km 0.6, Hermosillo, Sonora, Apartado Postal 1735, CP 83304, Mexico. lquihui@ciad.mx
authors.forename: Luis
authors.initials: L
authors.lastname: Quihui-Cota
authors.forename: Rosa Olivia
authors.initials: RO
authors.lastname: Méndez Estrada
authors.forename: Humberto
authors.initials: H
authors.lastname: Astiazarán-García
authors.forename: Gloria Guadalupe
authors.initials: GG
authors.lastname: Morales-Figueroa
authors.forename: Mario Jesús
authors.initials: MJ
authors.lastname: Moreno-Reyes
authors.forename: Denisse
authors.initials: D
authors.lastname: Cuadras-Romo
authors.forename: Rafael
authors.initials: R
authors.lastname: Canett-Romero
mesh_terms: D000818:Animals; D004032:Diet; D005873:Giardiasis / Q000097:blood*; D051379:Mice; D008809:Mice, Inbred C3H; D015032:Zinc / Q000008:administration & dosage* / Q000097:blood
chemical_list: D015032:Zinc