American Journal of Clinical Nutrition, Vol 66, 1218-1223, Copyright © 1997 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Effect of vitamin E supplementation on prostaglandin concentrations in aspirin-induced acute gastric injury in aged rats

F Stickel, M Meydani, D Wu, R Bronson, A Martin, D Smith, SN Meydani and RM Russell
Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston MA 02111, USA.

Nonsteroidal antiinflammatory drugs (NSAIDs), such as aspirin, frequently cause gastric mucosal injury in the elderly. Impairment of prostaglandin synthesis is a crucial step by which aspirin attenuates mucosal defense capacity. Vitamin E has been shown to decrease prostanoid concentrations, which implies an ulceropermissive effect of vitamin E. To assess the effect of vitamin E on aspirin-induced gastric injury and mucosal prostanoid concentrations, 20 male rats aged 20 mo were divided into two groups and fed diets containing either 30 (physiologic requirement) or 500 mg all-rac-alpha-tocopheryl acetate/kg. After 6 wk, all rats received two intragastric doses of aspirin (1.4 mumol/kg body wt). A third group of six animals fed the high-vitamin E diet received a vehicle solution without aspirin. Mucosal samples for vitamin E and prostaglandin E2, 6-keto- prostaglandin F1 alpha, and thromboxane A2 measurements were collected. The prevalence and degree of mucosal lesions were not significantly different among all groups. Rats fed the high-vitamin E diet had significantly higher mucosal vitamin E concentrations than rats fed the low-vitamin E diet. Mucosal concentrations of all three prostanoids were 95% lower in aspirin-treated rats than in controls (P = 0.0001 in all instances). The high-vitamin E diet group had significantly lower mucosal 6-keto-prostaglandin F1 alpha concentrations (P = 0.02) than the low-vitamin E diet group, indicating decreased prostacyclin formation, whereas concentrations of prostaglandin E2 and thromboxane A2 were similar in the aspirin-treated groups. Aspirin markedly reduced mucosal prostanoid concentrations in rats, without apparent effects on gastric injury, whereas vitamin E supplementation significantly reduced mucosal 6-keto-prostaglandin F(1 alpha) concentrations. Nevertheless, vitamin E supplementation did not result in more gastric injury in aspirin-treated rats than in controls.