有氧运动对DMBA诱导大鼠乳腺癌发生的影响及其机制的研究

Study on the effect of aerobic exercise on DMBA- induced breast cancer in rats and the mechanism

目的:研究有氧运动对二甲基苯蒽(DMBA)诱导大鼠乳腺癌发生的影响并探讨其可能的机制。方法:将120只8周龄雌性Sprague-Dawley(SD)大鼠随机分为空白对照组(CON)、运动对照组(ECON)、药物诱导组(DI)和运动+药物诱导组(EDI),每组30只。ECON组和EDI组进行有氧运动训练,运动强度为25 m/min,30 min/d,每周5天。DI组和EDI组分别给予1 ml 10 mg/ml的DMBA麻油溶液灌胃2次。每2周记录1次大鼠的体重、荷瘤数和乳腺肿瘤体。18周后处死所有大鼠,对大鼠乳房肿瘤进行病理诊断,处死大鼠前测定血清TNF-а、IL-6、CRP和sE-selectin水平。结果:实验结束时ECON组体重为(353.8±31.13)g,CON组体重为(325.7±28.52)g,两组相比体重明显下降,差异有统计学意义,P<0.05。DI组体重为(299.2±29.28)g,EDI组体重为(294.3±25.96)g,两组间比较,差异无统计学意义,P>0.05。DI组诱发乳腺癌概率(30/30)显著高于EDI组(24/30),两组之间比较,差异有统计学意义,P<0.05。DI组的潜伏期为(13.83±2.83)天,EDI组的潜伏期为(15.58±2.21)天,组间差异有统计学意义(P<0.05)。DI组的荷瘤数为3.03±1.16,EDI组的荷瘤数为2.21±1.06,组间比较,差异有统计学意义(P<0.05)。DI组的肿瘤体积为(2 185.03±528.21)mm3,EDI组的肿瘤体积为(1 763.08±519.44)mm3,组间比较,差异有统计学意义(P<0.05)。ECON组与CON组相比及EDI组与DI组相比,TNF-а、CRP、sE-selectin水平显著降低,血清IL-6水平显著升高,差异均有统计学意义(P<0.05)。结论:有氧运动可以抑制DMBA诱导大鼠乳腺癌的发生,降低全身慢性炎症水平可能是其作用机制之一。

Objective To research the effect of aerobic exercise on DMBA - induced breast cancer and possible mechanism inrats. Methods ： One hundred and twenty 8 - week - old female Sprague - Dawley （SD） rats were randomly divided into blank control group,exercise control group, drag - induced group and exercise ＋ drug - induced group, 30 rats in each group. The rats in exercise control groupand exercise ＋ drug - induced group received aerobic exercise training, 25 meters per minute, 30 minutes per day, five days a week; the ratsin drug - induced group and exercise ＋ drug - induced group were treated with intragastric administration of 1 ml DMBA （ 10 mg/ml） twice.Body weight, tumor - bearing number and incidence rate of palpable breast tumor were recorded once every two weeks. After 18 weeks, therats were sacrificed and pathological diagnosis of breast tumor was obtained; before killing the rats, serum levels of tumor necrosis factor - α（TNF- α）, interleukin- 6 （IL- 6）, C- reactive protein （CRP） and sE- selectin were detected. Results： After the experiment, thebody weights in exercise control group and blank control group were （353.8 ± 31.13 ） g and （325.7 ± 28.52 ） g, respectively, there wasstatistically significant difference between the two groups （ P 〈 0.05 ） ; the body weights in drug - induced group and exercise ＋ drug - induced group were （299.2 2 29.28 ） g and （294. 3 2 25.96） g, respectively, there was no statistically significant difference between the twogroups （P 〉 0.05 ） . The incidence rate of breast cancer in druginduced group （30/30） was statistically significantly higher than that inexercise ＋ drug - induced group （24/30） （ P 〈 0. 05 ） . The duration time of latent period in drug - induced group and exercise ＋ drug - in-duced group were （13.83 ± 2. 83 ） days and （15.58 ± 2. 21 ） days, respectively, there was statistically significant difference between the twogroups （ P 〈 0. 05 ） . The tumor - bearing numbers in drug - induced group and exercise ＋ drug - induced group were （ 3.03 ± 1.16 ） and（2. 21 ± 1.06 ）, respectively, there was statistically significant difference between the two groups （P 〈 0. 05 ） . The sizes of tumor in drug -induced group and exercise ＋ drug - induced group were （2 185.03±528.21 ） mm3 and （ 1 763.08 2519.44） mm3, respectively, there wasstatistically significant difference between the two groups （P 〈 0. 05 ） . The serum levels of TNF - or, CRP and sE - seleetin decreased sig-nificantly, the serum levels of IL - 6 increased significantly in exercise control group and exercise ＋ drug - induced group, compared withblank control group and drug - induced group, respectively, there were statistically significant differences （ P 〈 0. 05 ） . Conclusion： Aero-bic exercise can inhibit breast cancer induced by DMBA, the probable mechanism is reducing systemic chronic inflammation.