Westerlind Kim C, Williams Nancy I
Division of Endocrinology, Metabolism & Diabetes, School of Medicine, University of Colorado at Denver and Health Sciences Center, Denver, CO 80214, USA.
Med Sci Sports Exerc. 2007 Jul;39(7):1090-7. doi: 10.1097/mss.0b013e3180485727.
Physical activity has been associated with decreased breast cancer risk, potentially through changes in estrogen metabolism. Two-hydroxyestrone (2-OHE1) and 16alpha-hydroxyestrone (16alpha-OHE1) have different biological properties, and the ratio of these metabolites (2/16) has been proposed to predict breast cancer risk. Diet and exercise have been found to influence estrogen metabolism, particularly when a state of negative energy balance is achieved. We sought to determine whether 4 months of moderate-intensity exercise coupled with calorie restriction would result in changes in urinary 2-OHE1, 16alpha-OHE1, or 2/16 in sedentary, premenopausal, eumenorrheic women.
Average age was 31.5 yr, average body fat was 31.6%, and average BMI was 23.7. Urinary estrogen metabolites were measured in 24 women during the baseline and for four intervention months in the midfollicular and midluteal phases.
The intervention produced a significant drop in body fat (4.5%) and body weight (3.7 kg). Aerobic fitness increased significantly (26%; P < 0.001). Overall, there were no significant effects of the diet and exercise intervention on 2-OHE1, 16alpha-OHE1, or 2/16. However, when divided into tertiles according to baseline 2/16, the intervention resulted in significant increases in 2/16 in women in the lowest tertile. Women in the lowest tertile (average 2/16 = 0.91) did not differ from the other tertiles in baseline estradiol concentrations, body fat, weight, fitness, or changes in these variables with the intervention.
The data suggest that women at higher risk for developing breast cancer because of low 2/16 may reduce their risk by participating in lifestyle interventions such as exercise/calorie restriction.
体育活动与降低乳腺癌风险相关，可能是通过雌激素代谢的变化实现的。二羟雌酮（2-OHE1）和16α-羟雌酮（16α-OHE1）具有不同的生物学特性，并且有人提出这两种代谢物的比例（2/16）可用于预测乳腺癌风险。已发现饮食和运动可影响雌激素代谢，尤其是在实现负能量平衡状态时。我们试图确定，对于久坐不动、绝经前、月经正常的女性，进行4个月的中等强度运动并结合热量限制是否会导致尿中2-OHE1、16α-OHE1或2/16发生变化。
平均年龄为31.5岁，平均体脂为31.6%，平均体重指数为23.7。在24名女性的基线期以及卵泡期中期和黄体期中期的四个干预月期间测量尿雌激素代谢物。
干预使体脂显著下降（4.5%），体重显著下降（3.7千克）。有氧适能显著提高（26%；P<0.001）。总体而言，饮食和运动干预对2-OHE1、16α-OHE1或2/16没有显著影响。然而，根据基线2/16分为三分位数时，干预使最低三分位数的女性的2/16显著增加。最低三分位数的女性（平均2/16 = 0.91）在基线雌二醇浓度、体脂、体重、适能或这些变量在干预后的变化方面与其他三分位数的女性没有差异。
数据表明，因2/16较低而患乳腺癌风险较高的女性，可通过参与运动/热量限制等生活方式干预来降低风险。
