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

Abstract

Associations between Giardia lamblia infection and low serum concentrations of zinc have been reported in young children. Interestingly, relatively few studies have examined the effects of different dietary zinc levels on the parasite-infected host. The aims of this study were to compare the growth performance and zinc status in response to varying levels of dietary zinc and to measure the antibody-mediated response of mice during G. lamblia infection. Male CD-1 mice were fed using 1 of 4 experimental diets: adequate-zinc (ZnA), low-zinc (ZnL), high-zinc (ZnH) and supplemented-zinc (ZnS) diet containing 30, 10, 223 and 1383 mg Zn/kg respectively. After a 10 days feeding period, mice were inoculated orally with 5 × 106 G. lamblia trophozoites and were maintained on the assigned diet during the course of infection (30 days). Giardia-free mice fed ZnL diets were able to attain normal growth and antibody-mediated response. Giardia-infected mice fed ZnL and ZnA diets presented a significant growth retardation compared to non-infected controls. Zinc supplementation avoided this weight loss during G. lamblia infection and up-regulated the host’s humoral immune response by improving the production of specific antibodies. Clinical outcomes of zinc supplementation during giardiasis included significant weight gain, higher anti-G. lamblia IgG antibodies and improved serum zinc levels despite the ongoing infection. A maximum growth rate and antibody-mediated response were attained in mice fed ZnH diet. No further increases in body weight, zinc status and humoral immune capacity were noted by feeding higher zinc levels (ZnS) than the ZnH diet. These findings probably reflect biological effect of zinc that could be of public health importance in endemic areas of infection.

High-fat diet increases the severity of Giardia infection in association with low-grade inflammation and gut microbiota dysbiosis

“…Conversely, G. duodenalis infection impairs vitamin A absorption in malnourished children 23 . Serum levels of other trace elements such as zinc and iron are decreased during giardiasis 28,31,32,51,52 . In this context, diet intervention and nutrient supplementation have been explored as a therapeutic strategy.…”

Giardia spp. and the Gut Microbiota: Dangerous Liaisons

“…Diet and the host nutritional status are known to play a key role during parasitic infections ( Shea-Donohue et al, 2017 ). In giardiasis, micronutrient deficiencies, such as zinc, iron, and vitamin A, are associated with increased host susceptibility to infection, impaired immune responses and intestinal malabsorption in young individuals ( Duncombe et al, 1980 ; Astiazaran-Garcia et al, 2010 , 2015 ; Quihui-Cota et al, 2012 ; Bartelt et al, 2013 ; Inigo-Figueroa et al, 2013 ). Supplementation of micronutrients and trace elements in children led to a reduction of the frequency and severity of diarrhea and a decrease in infection rate, indicating that diet intervention may be considered as an efficient therapeutic strategy ( Lima et al, 2010 ; Astiazaran-Garcia et al, 2015 ).…”

Advances in understanding Giardia: determinants and mechanisms of chronic sequelae

“…In experimental models, malnutrition confers enhanced susceptibility to Cryptosporidium [ 126 – 128 ] and enteroaggregative Escherichia coli (EAEC) [ 129 ]. Zinc deficiency enhances susceptibility to Giardia [ 130 ] and diminishes inflammatory responses to EAEC [ 131 ]. In a chronic giardiasis model, protein malnutrition led to decreased expression of IL-4 and IL-5 and diminished B-cell populations in intestinal tissues, villus blunting, and growth failure despite a parasite burden similar to that of well-nourished infected controls [ 85 ].…”