Parry-Billings M, Budgett R, Koutedakis Y, Blomstrand E, Brooks S, Williams C, Calder P C, Pilling S, Baigrie R, Newsholme E A
Department of Biochemistry, University of Oxford, U.K.
Med Sci Sports Exerc. 1992 Dec;24(12):1353-8.
Overtraining and long-term exercise are associated with an impairment of immune function. We provide evidence in support of the hypothesis that the supply of glutamine, a key fuel for cells of the immune system, is impaired in these conditions and that this may contribute to immunosuppression. Plasma glutamine concentration was decreased in overtrained athletes and after long-term exercise (marathon race) and was increased after short-term, high intensity exercise (sprinting). Branched chain amino acid supplementation during long-term exercise was shown to prevent this decrease in the plasma glutamine level. Overtraining was without effect on the rate of T-lymphocyte proliferation in vitro or on the plasma levels of interleukin-1 and -6, suggesting that immune function is not impaired in this condition. Given the proposed importance of glutamine for cells of the immune system, it is concluded that the decrease in plasma glutamine concentration in overtraining and following long-term exercise, and not an intrinsic defect in T lymphocyte function, may contribute to the immune deficiency reported in these conditions.
过度训练和长期运动与免疫功能受损有关。我们提供证据支持这样的假说：在这些情况下，免疫系统细胞的关键燃料谷氨酰胺的供应受到损害，这可能导致免疫抑制。过度训练的运动员以及长期运动（马拉松比赛）后血浆谷氨酰胺浓度降低，而短期高强度运动（短跑）后则升高。长期运动期间补充支链氨基酸可防止血浆谷氨酰胺水平下降。过度训练对体外T淋巴细胞增殖率或白细胞介素-1和-6的血浆水平没有影响，这表明在这种情况下免疫功能没有受损。鉴于谷氨酰胺对免疫系统细胞的重要性，得出的结论是，过度训练和长期运动后血浆谷氨酰胺浓度的降低，而非T淋巴细胞功能的内在缺陷，可能导致这些情况下所报道的免疫缺陷。
