The effect of Helicobacter pylori infection and dietary iron deficiency on host iron homeostasis: a study in mice.
BACKGROUND
Helicobacter pylori, which requires iron to survive, may cause host iron deficiency by directly competing with the host for available iron or by impairing iron uptake as a consequence of atrophy-associated gastric hypochlorhydria. The aim of this study was to examine the effect of H. pylori infection and dietary iron deficiency on host iron homeostasis in a mouse model.


METHODS
H. pylori SS1-infected and uninfected C57BL/6 mice, fed either a normal diet or an iron-deficient diet, were assessed for iron status and infection-associated gastritis over a 30-week period.


RESULTS
After 10 weeks, serum ferritin values were higher in H. pylori-infected mice than in uninfected controls, irrespective of dietary iron intake (p = .04). The infection-related increase in body iron stores persisted in the iron-replete mice but diminished over time in mice with restricted dietary iron intake (p < .0001). At 30 weeks serum ferritin levels were lower in these animals (p = .063). No significant difference in bacterial numbers was detected at the 30-week time point (p > .05) and the histological changes observed were consistently associated with infection (p < .01) and not with the iron status of the mice (p = .771).


CONCLUSIONS
Infection with H. pylori did not cause iron deficiency in iron-replete mice. However, diminished iron stores in mice as a result of limited dietary iron intake were further lowered by concurrent infection, thus indicating that H. pylori competes successfully with the host for available iron.
Keenan
J I
JI
Department of Surgery, Christchurch School of Medicine and Health Sciences, Christchurch, New Zealand. jacqui.keenan@chmeds.ac.nz
Peterson
R A
RA
Fraser
R
R
Frampton
C M
CM
Walmsley
T A
TA
Allardyce
R A
RA
Roake
J A
JA
D000818:Animals; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D005293:Ferritins / Q000097:blood; D005753:Gastric Mucosa / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000378:metabolism*; D006706:Homeostasis; D007501:Iron / Q000378:metabolism*; D000090463:Iron Deficiencies; D008099:Liver / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL
D005293:Ferritins; D007501:Iron