Alpha-tocopherol attenuates lung edema and lipid peroxidation caused by acute zymosan-induced peritonitis.
BACKGROUND
Inflammation-induced disease as seen with trauma and infection can lead to increased lung oxidant activity resulting in cell membrane lipid peroxidation. Acute zymosan-induced peritonitis in rats produces lung inflammation, edema, and lipid peroxidation. We determined whether administered alpha-tocopherol (vitamin E), the key antioxidant protection against cell membrane lipid peroxidation, would improve this process.


METHODS
Male Wistar rats were given 0.75 mg/kg of intraperitoneal zymosan, volume resuscitated, monitored, and killed at 4 or 24 hours. Lung histologic changes and levels of conjugated dienes, a marker of lipid peroxidation, were used to monitor injury. The levels of vitamin E, vitamin C, and catalase were used to monitor antioxidant defenses. The effect of administering alpha-tocopherol (50 mg/kg) by gavage immediately after zymosan on the degree of the lung injury was then determined.


RESULTS
Twenty-four hours after zymosan was administered, the vitamin E levels in plasma were significantly decreased, but lung tissue vitamin E levels were maintained, whereas tissue catalase and vitamin E levels decreased. Lung tissue-conjugated diene levels, alveolar edema, and neutrophil count were significantly increased. alpha-Tocopherol treatment increased the postzymosan plasma vitamin E levels by 50%. Lung tissue vitamin E levels did not increase; however, the degree of lung injury and lipid peroxidation was significantly attenuated. Tissue catalase levels were also maintained.


CONCLUSIONS
We conclude that alpha-tocopherol given at the onset of a progressing inflammatory injury can protect the lung from oxidant damage and attenuate the degree of lung injury.
Longwood Area Trauma Center, Brigham and Women's Hospital, Boston, MA 02115.
R
R
Demling
C
C
LaLonde
K
K
Ikegami
L
L
Picard
U
U
Nayak
D000208:Acute Disease; D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008168:Lung / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008297:Male; D010538:Peritonitis / Q000139:chemically induced / Q000150:complications*; D011654:Pulmonary Edema / Q000209:etiology / Q000517:prevention & control*; D051381:Rats; D017208:Rats, Wistar; D014810:Vitamin E / Q000378:metabolism / Q000627:therapeutic use*; D015054:Zymosan
D014810:Vitamin E; D015054:Zymosan; D002374:Catalase; D001205:Ascorbic Acid