Responses of Intestinal Microbiota and Immunity to Increasing Dietary Levels of Iron Using a Piglet Model

Abstract

Iron is an essential metal for both animals and microbiota. In general, neonates and infants of humans and animals are at the risk of iron insufficiency. However, excess dietary iron usually causes negative impacts on the host and microbiota. This study aimed to investigate overloaded dietary iron supplementation on growth performance, the distribution pattern of iron in the gut lumen and the host, intestinal microbiota, and intestine transcript profile of piglets. Sixty healthy weaning piglets were randomly assigned to six groups: fed on diets supplemented with ferrous sulfate monohydrate at the dose of 50 ppm (Fe50 group), 100 ppm (Fe100 group), 200 ppm (Fe200 group), 500 ppm (Fe500 group), and 800 ppm (Fe800), separately, for 3 weeks. The results indicated that increasing iron had no significant effects on growth performance, but increased diarrheal risk and iron deposition in intestinal digesta, tissues of intestine and liver, and serum. High iron also reduced serum iron-binding capacity, apolipoprotein, and immunoglobin A. The RNA-sequencing analysis revealed that iron changed colonic transcript profile, such as interferon gamma-signal transducer and activator of transcription two-based anti-infection gene network. Increasing iron also shifted colonic and cecal microbiota, such as reducing alpha diversity and the relative abundance of Clostridiales and Lactobacillus reuteri and increasing the relative abundance of Lactobacillus and Lactobacillus amylovorus. Collectively, this study demonstrated that high dietary iron increased diarrheal incidence, changed intestinal immune response-associated gene expression, and shifted gut microbiota. The results would enhance our knowledge of iron effects on the gut and microbiome in piglets and further contribute to understanding these aspects in humans.

Perturbations in lipid metabolism and gut microbiota composition precede cardiac dysfunction in a mouse model of thalassemia

“…Interestingly, previous literature indicated a possible positive correlation between Actinobacteria and PC(39:6), 73 which match what we have observed here of PC(39:6) with Enterorhabdus. In addition, a link or possibly a positive correlation between the abundance of Lactobacillus and the host's absorption/absorption rate of Fe was observed, 74,75 which matches our study of a slightly greater (although not significant) abundance of Lactobacillus in the Th3/+ mouse compared to the control group. Nevertheless, establishing causality between altered intestinal microbiome and metabolic dysfunction requires follow-up studies involving recolonization of germ-free or antibiotics-treated Th3/+ mice.…”

Association between iron supplementation and the presence of diarrhoea in Peruvian children aged 6–59 months: analysis of the database of the Demographic and Family Health Survey in Peru (DHS, Peru), years 2009–2019

“…This would suggest that children who received supplementation in the last 12 months and who present diarrhoea could be receiving excess Fe. The excessive Fe concentrations not being absorbed in the duodenum would enter the colon and be used by pathogenic bacteria to the detriment of commensal bacteria (31) . The amount of Fe in supplementation modifies the composition of the infant gut microbiota and increases faecal calprotectin levels, a marker of gut inflammation associated with an increased incidence of diarrhoea (23) .…”

The Administration Effect of Lactic Acid Bacteria Reducing Environmental Alkyl and Fatty Acid Hydroperoxides on Piglets in the Absence of Antimicrobial Agents and in the Presence of Iron

“…However, iron is a factor that causes the Fenton reaction [13], and iron administration cause energy depletion in piglets with immature oxidative stress defense systems [32]. Therefore, setting the iron dosage according to the rearing condition of piglets is a very important issue in iron-administered rearing [10,11,[33][34][35][36].…”

“…In piglet rearing, iron supplements are administered to piglets to prevent iron deficiency anemia during the growth process [10][11][12]. However, since iron is a factor that causes the Fenton reaction [13], piglets with immature oxidative stress defense systems may exhaust energy to cope with such stress.…”