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Med Hypotheses. 2004 Mar;62(3):442-5. Related Articles, Links
Serum markers of stored body iron are not appropriate markers of health effects of iron: a focus on
serum ferritin.
Lee DH, Jacobs DR Jr.
Experimental studies have consistently shown that iron is a critical catalyst in generating oxygen
free radicals via Fenton chemistry. Nevertheless, epidemiologic studies conflict on the association
between stored body iron markers and disease outcomes, including coronary heart disease. We
hypothesize that stored body iron markers common in epidemiologic studies, such as serum ferritin,
transferrin saturation, iron, or iron-binding capacity, are inappropriate to investigate harmful
health effects related to iron overload. Oxygen free radicals are produced only by free iron, but
stored body iron markers reflect iron bound to ferritin or transferrin, which are produced to
sequester catalytically active free iron. Moreover, increased serum ferritin may occur as a defense
mechanism in response to oxidative stress; such increase might eventually minimize oxidative stress
and consequent pathology due to free iron. Therefore, though highly correlated with stored body
iron, a measure of bound iron will fail to identify any harmful effect, unless it is also a marker
of free iron. It is generally believed that free iron rarely exists, except in iron-overload with
100% transferrin saturation. However, some recent studies find non-transferrin bound iron (NTBI) or
the intracellular labile iron pool
(LIP) in the presence of triggers disturbing iron homeostasis, such as alcohol consumption. In
contrast to the tight bond in ferritin or transferrin, free iron is more likely to dissociate
from a looser bond. Therefore research on the relation of iron with disease outcomes should
investigate NTBI or the intracellular LIP. Any positive influence of iron on coronary heart
and other diseases might be observable only when a trigger is present. These factors may
explain why there have been conflicting results between serum markers of stored body iron and
disease outcomes in epidemiological studies.
PMID: 14975519 [PubMed - in process]
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http://pages.ivillage.com/ironjustice/manisaherbivore DEAD PEOPLE WALKING
http://pages.ivillage.com/ironjustice/deadpeoplewalking
Serum markers of stored body iron are not appropriate markers of health effects of iron: a focus on
serum ferritin.
Lee DH, Jacobs DR Jr.
Experimental studies have consistently shown that iron is a critical catalyst in generating oxygen
free radicals via Fenton chemistry. Nevertheless, epidemiologic studies conflict on the association
between stored body iron markers and disease outcomes, including coronary heart disease. We
hypothesize that stored body iron markers common in epidemiologic studies, such as serum ferritin,
transferrin saturation, iron, or iron-binding capacity, are inappropriate to investigate harmful
health effects related to iron overload. Oxygen free radicals are produced only by free iron, but
stored body iron markers reflect iron bound to ferritin or transferrin, which are produced to
sequester catalytically active free iron. Moreover, increased serum ferritin may occur as a defense
mechanism in response to oxidative stress; such increase might eventually minimize oxidative stress
and consequent pathology due to free iron. Therefore, though highly correlated with stored body
iron, a measure of bound iron will fail to identify any harmful effect, unless it is also a marker
of free iron. It is generally believed that free iron rarely exists, except in iron-overload with
100% transferrin saturation. However, some recent studies find non-transferrin bound iron (NTBI) or
the intracellular labile iron pool
(LIP) in the presence of triggers disturbing iron homeostasis, such as alcohol consumption. In
contrast to the tight bond in ferritin or transferrin, free iron is more likely to dissociate
from a looser bond. Therefore research on the relation of iron with disease outcomes should
investigate NTBI or the intracellular LIP. Any positive influence of iron on coronary heart
and other diseases might be observable only when a trigger is present. These factors may
explain why there have been conflicting results between serum markers of stored body iron and
disease outcomes in epidemiological studies.
PMID: 14975519 [PubMed - in process]
--------------------------------------------------------------------------
------
Who loves ya. Tom Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com Man Is A Herbivore!
http://pages.ivillage.com/ironjustice/manisaherbivore DEAD PEOPLE WALKING
http://pages.ivillage.com/ironjustice/deadpeoplewalking