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.

Effects of Dietary Zinc Manipulation on Growth Performance, Zinc Status and Immune Response during Giardia lamblia Infection: A Study in CD-1 Mice

“…In our study, Giardia -infected mice in all dietary groups had lower serum zinc levels than non-infected mice after 30 days p.i. This is in agreement with other authors whose studies showed that giardiasis may be a risk factor for zinc deficiency in mice regardless of the dietary intake [35]. However, the “extra” zinc provided by the ZnH and ZnS diets helped maintaining the zinc levels near those of the ZnA Giardia -free mice.…”

Marked Antigiardial Activity ofYucca baccataExtracts: A Potential Natural Alternative for Treating Protozoan Infections

“…Trophozoites on each 1 mm² square (4 in total) were microscopically counted at 40x magnification (Microscope Olympus, CKX41, Center Valley, PA, USA). The total number of trophozoites per mL was calculated as follows: (Number of trophozoites/4 squares) × (500/100) × 10000 [26]. …”

The micronutrient zinc inhibits EAEC strain 042 adherence, biofilm formation, virulence gene expression, and epithelial cytokine responses benefiting the infected host

“…Although anti-microbial effects of zinc have been reported for several pathogenic species, including EPEC, ETEC, and STEC, [21][22][23][24][25] Therefore, we sought to investigate whether zinc has a potential role in EAEC-host cell interaction at concentrations similar to physiological serum and intestinal lumen levels (0.01-0.05 mM). 26,27 The objectives of this study were to elucidate the effects of zinc on important properties of a strain of EAEC (042) associated with human disease, 28 as it interacts with intestinal epithelium, and to begin to identify specific mechanisms in vitro responsible for these effects.…”