Pretreatment of young pigs with vitamin E attenuates the elevation in plasma interleukin-6 and cortisol caused by a challenge dose of lipopolysaccharide.

The effect of a short-term, high-dose intramuscular injection of d-alpha-tocopherol was studied in pigs given a challenge dose of lipopolysaccharide (LPS). Twenty-four pigs surgically fitted with jugular catheters were used in a 2 x 2 factorial design. Pigs received either 0 or 600 mg d-alpha-tocopherol by intramuscular injection for 3 d before receiving an intraperitoneal injection of saline containing either 0 or 5 microgram/kg body weight Escherichia coli LPS. Blood was collected from indwelling jugular catheters at 0, 1, 2, 4, 6, 8, 12 and 24 h after injection of LPS. Plasma alpha-tocopherol levels were 13-fold greater (P < 0.01) at time 0 in pigs pretreated with 600 mg d-alpha-tocopherol (9.9 +/- 1.3 mg/L) than in those not treated with d-alpha-tocopherol (0.74 +/- 0.09 mg/L). Injection of LPS increased (P < 0.05) plasma levels of interleukin-6 (IL-6) and cortisol at 2-h postinjection, regardless of vitamin E treatment. However, pigs that received alpha-tocopherol before the LPS challenge had substantially lower (P < 0.05) peak levels of IL-6 and cortisol than pigs not receiving alpha-tocopherol. These results suggest that supplementation with a surfeit level of vitamin E reduces the response of pigs to endotoxin.