Dietary restriction of iron availability attenuates UPEC pathogenesis in a mouse model of urinary tract infection

Am J Physiol Renal Physiol. 2019 May 1;316(5):F814-F822. doi: 10.1152/ajprenal.00133.2018. Epub 2019 Feb 6.

Abstract

Iron is a critical nutrient required by hosts and pathogens. Uropathogenic Escherichia coli (UPEC), the principal causative agent of urinary tract infections (UTIs), chelate iron for their survival and persistence. Here, we demonstrate that dietary modulation of iron availability limits UPEC burden in a mouse model of UTI. Mice on a low-iron diet exhibit reduced systemic and bladder mucosal iron availability and harbor significantly lower bacterial burden, concomitant with dampened inflammation. Hepcidin is a master regulator of iron that controls iron-dependent UPEC intracellular growth. Hepcidin-deficient mice ( Hamp1-/-) exhibit accumulation of iron deposits, persistent bacterial burden in the bladder, and a heightened inflammatory response to UTI. However, a low-iron dietary regimen reversed the iron overload and increased bacterial burden phenotypes in Hamp1-/- mice. Thus modulation of iron levels via diet can reduce UPEC infection and persistence, which may have significant implications for clinical management of UTI.

Keywords: IL-6; ferritin; hepcidin; uropathogenic; urothelium.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Load
  • Disease Models, Animal
  • Escherichia coli Infections / diet therapy*
  • Escherichia coli Infections / metabolism
  • Escherichia coli Infections / microbiology
  • Ferritins / metabolism
  • Hepcidins / genetics
  • Hepcidins / metabolism
  • Host-Pathogen Interactions
  • Interleukin-6 / metabolism
  • Iron, Dietary / metabolism*
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Urinary Bladder / metabolism
  • Urinary Bladder / microbiology*
  • Urinary Tract Infections / diet therapy*
  • Urinary Tract Infections / metabolism
  • Urinary Tract Infections / microbiology
  • Uropathogenic Escherichia coli / pathogenicity*

Substances

  • Hamp protein, mouse
  • Hepcidins
  • Interleukin-6
  • Iron, Dietary
  • interleukin-6, mouse
  • Ferritins