Effects of marginal iron overload on iron homeostasis and immune function in alveolar macrophages isolated from pregnant and normal rats.
The effects of changes in macrophage iron status, induced by single or multiple iron injections, iron depletion or pregnancy, on both immune function and mRNA expression of genes involved in iron influx and egress have been evaluated. Macrophages isolated from iron deficient rats, or pregnant rats at day 21 of gestation, either supplemented with a single dose of iron dextran, 10 mg, at the commencement of pregnancy, or not, showed significant increases of macrophage ferroportin mRNA expression, which was paralleled by significant decreases in hepatic Hamp mRNA expression. IRP activity in macrophages was not significantly altered by iron status or the inducement of pregnancy +/- a single iron supplement. Macrophage immune function was significantly altered by iron supplementation and pregnancy. Iron supplementation, alone or combined with pregnancy, increased the activities of both NADPH oxidase and nuclear factor kappa B (NFkappaB). In contrast, the imposition of pregnancy reduced the ability of these parameters to respond to an inflammatory stimuli. Increasing iron status, if only marginally, will reduce the ability of macrophages to mount a sustained response to inflammation as well as altering iron homeostatic mechanisms.
Ward
Roberta J
RJ
Unite de Biochimie, Département de Chimie, Université Catholique de Louvain, Louvain-la-Neuve, Belgium. ward@bioc.ucl.ac.be
Wilmet
Stephanie
S
Legssyer
Rachida
R
Leroy
Daniel
D
Toussaint
Louise
L
Crichton
Robert R
RR
Pierreux
Christophe
C
Hue
Louis
L
Piette
Jacques
J
Srai
Surjit Kaila
SK
Solanky
Nita
N
Klein
Dominique
D
Summer
Karl
K
D000818:Animals; D005260:Female; D006706:Homeostasis; D007107:Immune System; D007249:Inflammation; D007501:Iron / Q000633:toxicity*; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism; D019255:NADPH Oxidases / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D011247:Pregnancy; D011270:Pregnancy, Animal; D011650:Pulmonary Alveoli / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D016328:NF-kappa B; D007501:Iron; D019001:Nitric Oxide Synthase; D019255:NADPH Oxidases