ironjustice
2009-07-05 05:49:47 UTC
"Iron Accelerates Thrombosis"
http://circ.ahajournals.org/cgi/content/full/107/20/2601
Basic Science Reports
Chronic Iron Administration Increases Vascular Oxidative Stress
and Accelerates Arterial Thrombosis
Circulation. 2003;107:2601-2606Sharlene M. Day, MD;
Damon Duquaine, BS; Lakshmi V. Mundada, MS;
Rekha G. Menon, MD; Bobby V. Khan, MD, PhD;
Sanjay Rajagopalan, MD; William P. Fay, MD
From the University of Michigan Medical School,
Division of Cardiology, Ann Arbor
(S.M.D., D.D., L.V.M., S.R., W.P.F.); and
Emory University School of Medicine,
Division of Cardiology, Atlanta, Ga (R.G.M., B.V.K.).
Correspondence to Sharlene M. Day, MD,
University of Michigan Medical Center,
7301 MSRB III, 1150 W Medical Center Dr,
Ann Arbor, MI 48109-0644.
E-mail ***@umich.edu
Abstract
Background—
Iron overload has been implicated in the
pathogenesis of ischemic cardiovascular events.
However, the effects of iron excess on vascular function
and the thrombotic response to vascular injury are not
well understood.
Methods and Results—
We examined the effects of chronic iron dextran
administration (15 mg over 6 weeks) on thrombosis,
systemic and vascular oxidative stress, and
endothelium-dependent vascular reactivity in mice.
Thrombus generation after photochemical carotid
artery injury was accelerated in iron-loaded mice
(mean time to occlusive thrombosis, 20.4±8.5 minutes;
n=10) compared with control mice (54.5±35.5 minutes, n=10,
P=0.009).
Iron loading had no effect on plasma clotting, vessel
wall tissue factor activity, or ADP-induced platelet
aggregation.
Acute administration of DL-cysteine, a reactive oxygen
species scavenger, completely abrogated the effects of iron
loading on thrombus formation, suggesting that iron
accelerated thrombosis through a pro-oxidant mechanism.
Iron loading enhanced both systemic and vascular reactive
oxygen species production.
Endothelium-dependent vasorelaxation was impaired in
iron-loaded mice, indicating reduced NO bioavailability.
Conclusions—
Moderate iron loading markedly accelerates thrombus
formation after arterial injury, increases vascular
oxidative stress, and impairs vasoreactivity.
Iron-induced vascular dysfunction may contribute to
the increased incidence of ischemic cardiovascular
events that have been associated with chronic iron
overload.
Key Words: thrombosis • free radicals • arteries
Published online before print May 5, 2003,
doi: 10.1161/01.CIR.0000066910.02844.D0
(Circulation. 2003;107:2601.)
© 2003 American Heart Association, Inc.
--------------------
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http://circ.ahajournals.org/cgi/content/full/107/20/2601
Basic Science Reports
Chronic Iron Administration Increases Vascular Oxidative Stress
and Accelerates Arterial Thrombosis
Circulation. 2003;107:2601-2606Sharlene M. Day, MD;
Damon Duquaine, BS; Lakshmi V. Mundada, MS;
Rekha G. Menon, MD; Bobby V. Khan, MD, PhD;
Sanjay Rajagopalan, MD; William P. Fay, MD
From the University of Michigan Medical School,
Division of Cardiology, Ann Arbor
(S.M.D., D.D., L.V.M., S.R., W.P.F.); and
Emory University School of Medicine,
Division of Cardiology, Atlanta, Ga (R.G.M., B.V.K.).
Correspondence to Sharlene M. Day, MD,
University of Michigan Medical Center,
7301 MSRB III, 1150 W Medical Center Dr,
Ann Arbor, MI 48109-0644.
E-mail ***@umich.edu
Abstract
Background—
Iron overload has been implicated in the
pathogenesis of ischemic cardiovascular events.
However, the effects of iron excess on vascular function
and the thrombotic response to vascular injury are not
well understood.
Methods and Results—
We examined the effects of chronic iron dextran
administration (15 mg over 6 weeks) on thrombosis,
systemic and vascular oxidative stress, and
endothelium-dependent vascular reactivity in mice.
Thrombus generation after photochemical carotid
artery injury was accelerated in iron-loaded mice
(mean time to occlusive thrombosis, 20.4±8.5 minutes;
n=10) compared with control mice (54.5±35.5 minutes, n=10,
P=0.009).
Iron loading had no effect on plasma clotting, vessel
wall tissue factor activity, or ADP-induced platelet
aggregation.
Acute administration of DL-cysteine, a reactive oxygen
species scavenger, completely abrogated the effects of iron
loading on thrombus formation, suggesting that iron
accelerated thrombosis through a pro-oxidant mechanism.
Iron loading enhanced both systemic and vascular reactive
oxygen species production.
Endothelium-dependent vasorelaxation was impaired in
iron-loaded mice, indicating reduced NO bioavailability.
Conclusions—
Moderate iron loading markedly accelerates thrombus
formation after arterial injury, increases vascular
oxidative stress, and impairs vasoreactivity.
Iron-induced vascular dysfunction may contribute to
the increased incidence of ischemic cardiovascular
events that have been associated with chronic iron
overload.
Key Words: thrombosis • free radicals • arteries
Published online before print May 5, 2003,
doi: 10.1161/01.CIR.0000066910.02844.D0
(Circulation. 2003;107:2601.)
© 2003 American Heart Association, Inc.
--------------------
Who loves ya.
Tom
Jesus Was A Vegetarian!
http://tinyurl.com/2r2nkh
Man Is A Herbivore!
http://tinyurl.com/4rq595
DEAD PEOPLE WALKING
http://tinyurl.com/zk9fk