Klurfeld D M, Welch C B, Davis M J, Kritchevsky D
Wistar Institute of Anatomy and Biology, Philadelphia, PA 19104.
J Nutr. 1989 Feb;119(2):286-91. doi: 10.1093/jn/119.2.286.
This study was designed to determine the degree of energy restriction necessary to achieve significant inhibition of mammary tumor promotion in rats treated with 7,12-dimethylbenz[a]anthracene (DMBA). A control group of rats was fed a diet containing 5% corn oil ad libitum. Four other groups were pair-fed to the controls; these rats were subjected to energy restriction of 10, 20, 30, or 40%. Weight gains among the groups were proportional to energy intake. The differences in weight were due primarily to reductions in body fat stores. Tumor incidence was reduced slightly by 20% calorie restriction and significantly by 30 and 40% restriction. There were also reductions in number of tumors per tumor-bearing rat and in mean tumor weight. The groups subjected to 30 and 40% energy restriction had significantly reduced serum levels of insulin in the fasting state. These data suggest that body weight, body fat, and fasting serum insulin correlate with susceptibility to mammary tumor promotion and that insulin may be a growth factor for DMBA-induced tumors.
本研究旨在确定在用7,12-二甲基苯并[a]蒽（DMBA）处理的大鼠中，实现对乳腺肿瘤促进的显著抑制所需的能量限制程度。一组对照大鼠随意进食含5%玉米油的饲料。另外四组与对照组配对喂食；这些大鼠分别接受10%、20%、30%或40%的能量限制。各组间体重增加与能量摄入成正比。体重差异主要归因于体脂储备的减少。20%的热量限制使肿瘤发生率略有降低，30%和40%的限制则使其显著降低。每只患瘤大鼠的肿瘤数量和平均肿瘤重量也有所减少。接受30%和40%能量限制的组在禁食状态下血清胰岛素水平显著降低。这些数据表明，体重、体脂和空腹血清胰岛素与乳腺肿瘤促进易感性相关，且胰岛素可能是DMBA诱导肿瘤的生长因子。
