Malondialdehyde levels are used in this research as a determining factor of free radical
mediated cell injury in burn trauma.
1. Horton, Jureta W.
JOURNAL NAME- Toxicology VOL. 189 NO. 1-2 July 15th 2003 2003 PP. 75-88.
DOCUMENT TYPE- Article ISSN- 0300-483X
ADDRESS- Department of Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas,
TX, 75390-9160, USA
Burn trauma produces significant fluid shifts that, in turn, reduce cardiac output and tissue perfusion. Treatment
approaches to major burn injury include administration of crystalloid solutions to correct hypovolemia and to
restore peripheral perfusion. While this aggressive postburn volume replacement increases oxygen delivery to
previously ischemic tissue, this restoration of oxygen delivery is thought to initiate a series of deleterious
events that exacerbate ischemia-related tissue injury. While persistent hypoperfusion after burn trauma would
produce cell death, volume resuscitation may exacerbate the tissue injury that occurred during low flow state. It
is clear that after burn trauma, tissue adenosine triphosphate (ATP) levels gradually fall, and increased adenosine
monophosphate (AMP) is converted to hypoxanthine, providing substrate for xanthine oxidase. These complicated
reactions produce hydrogen peroxide and superoxide, clearly recognized deleterious free radicals. In addition to
xanthine oxidase related free radical generation in burn trauma, adherent-activated neutrophils produce additional
free radicals. Enhanced free radical production is paralleled by impaired antioxidant mechanisms; as indicated by
burn-related decreases in superoxide dismutase, catalase, glutathione, alpha tocopherol, and ascorbic acid levels.
Burn related upregulation of inducible nitric oxide synthase (iNOS) may produce peripheral vasodilatation,
upregulate the transcription factor nuclear factor kappa B (NF-kappaB), and promote transcription and translation
of numerous inflammatory cytokines. NO may also interact with the superoxide radical to yield peroxynitrite, a
highly reactive mediator of tissue injury. Free radical mediated cell injury has been supported by postburn
increases in systemic and tissue levels of lipid peroxidation products such as conjugated dienes, thiobarbituric
acid reaction products, or malondialdehyde ( MDA ) levels Antioxidant therapy in burn therapy (ascorbic acid,
glutathione, N-acetyl-L-cysteine, or vitamins A, E, and C alone or in combination) have been shown to reduce burn
and burn/sepsis mediated mortality, to attenuate changes in cellular energetics, to protect microvascular
circulation, reduce tissue lipid peroxidation, improve cardiac output, and to reduce the volume of required fluid
resuscitation. Antioxidant vitamin therapy with fluid resuscitation has also been shown to prevent burn related
cardiac NF-kappaB nuclear migration, to inhibit cardiomyocyte secretion of TNF-alpha , IL -1beta, and IL-6, and to improve cardiac contractile
function. These data collectively support the hypothesis that cellular oxidative stress is a critical step in
burn-mediated injury, and suggest that antioxidant strategies designed to either inhibit free radical formation (
malondialdehyde ) or to scavage free radicals may provide organ protection in patients with burn injury.
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