Endotoxin and lipid peroxidation in vivo in selenium- and vitamin E-deficient and -adequate rats.

The effect of Salmonella typhimurium endotoxin injected intraperitoneally (0.5 mg/kg body weight) on lipid peroxidation in vivo was assessed. Peroxidation was monitored by measuring ethane production, an autoxidation product of (n-3) unsaturated fatty acids. Weanling rats were fed a selenium- and vitamin E-deficient basal diet or one supplemented with 0.2 mg Se/kg and/or 200 mg vitamin E/kg. After 11 to 13 wk of feeding, ethane production was tripled in LPS-treated Se- and vitamin E-deficient rats compared to saline-treated deficient rats. In both doubly deficient and adequate rats, LPS increased ethane production, but it did so to a greater extent in Se- and vitamin E-deficient rats. Dietary Se or vitamin E supplementation alone significantly reduced ethane production from LPS-treated rats. Vitamin E was more protective than Se against LPS-induced lipid peroxidation. Escherichia coli and Salmonella minnesota LPS also increased ethane production in Se- and vitamin E-deficient rats. These results show that low doses of LPS stimulate lipid peroxidation in vivo in Se- and vitamin E-deficient rats.