来曲唑对子宫内膜异位症大鼠TNF-α、IL-6、NF-κB表达的影响

Effect of letrozole on expression of TNF-α、IL-6、NF-κB in endometriosis rats model

目的:研究不同剂量来曲唑对大鼠子宫内膜异位症(EMs)模型的治疗作用及其对异位病灶中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、核转录因子-κB(NF-κB)表达的影响。方法:将建模成功的大鼠随机分为来曲唑组(低、中、高剂量组)、米非司酮组及生理盐水空白对照组。灌胃4周后采用自定义疼痛评分及阴道痛觉过敏实验评价大鼠疼痛情况;观察异位内膜生长情况;放射免疫法测定血清E2、P、T水平;应用免疫组化法检测TNF-α、IL-6、NF-κB蛋白表达;用逆转录聚合酶链反应(RT-PCR)技术检测TNF-α mRNA、IL-6 mRNA、NF-κB mRNA的含量。结果:来曲唑各组异位病灶体积明显缩小或萎缩,与空白对照组比较差异均有统计学意义(P<0.05);来曲唑中、高剂量组与低剂量组、米非司酮组相比较,异位病灶体积缩小更明显(P<0.05)。治疗后各组大鼠血清E2、P水平均无显著差异(P>0.05),但来曲唑组大鼠血清T水平升高,且呈剂量依赖性(P<0.05)。来曲唑治疗后模型鼠疼痛评分降低,与对照组比较差异有统计学意义(P<0.05),且高剂量来曲唑组较米非司酮组疼痛减轻更明显(P<0.05)。在20、30、40mmHg阴道压力的刺激下,米非司酮组和来曲唑组大鼠的逃避率较空白组显著降低(P<0.05),较少发生痛觉过敏,而在压力为5、10mmHg时,各组间逃避率的差异无统计学意义(P>0.05)。各治疗组异位内膜中TNF-α、IL-6、NF-κB蛋白和mRNA的表达,均较空白组显著降低(P<0.05),尤以高剂量来曲唑组蛋白表达最低。NF-κB与TNF-α、IL-6的表达均呈正相关(P<0.05)。结论:来曲唑对大鼠异位病灶体积影响明显,可缓解EMs引起的疼痛。这可能是通过降低异位病灶局部雌激素水平,降调TNF-α、IL-6、NF-κB在异位内膜组织中的表达而发挥治疗作用的。

Objective：To explore the effect of the treatment and the expression of tumor necrosis factor-alpha（TNF-α）,interleukin-6（IL-6）,nuclear transcription factor kappa B（NF-κB） in endometriosis rat models with the different doses of letrozole.Methods：The autologous transplantation method to establish rats endometriosis animal model,the successful models were randomly divided into letrozole group（low,medium and high dose group）,mifepristone group and control group.Four weeks after treatment,to observe the growth of ectopic endometrial situation.To measure serum E2,P,T levels by radioimmunoassay.To evaluate rats pain with the pain score and vaginal hyperalgesia test.The immunohistochemical method was used to detect TNF-α,IL-6,NF-κB protein and the reverse transcription-polymerase chain reaction（RT-PCR） was used to detect TNF-α mRNA,IL-6 mRNA,NF-κB mRNA in the ectopic endometrium of models.Results：Each letrozole group significantly reduced the volume of ectopic lesions or atrophy,compared with the control group and mifepristone group（P0.05）.Medium dose,high dose group were significantly more than low dose group（P0.05）.The serum E2 and P levels were not significant different（P0.05）,but letrozole elevated T levels.After letrozole treatment,rat model of pain scores were reduced,the difference was statistically significant with the control group（P0.05）,and high doses of letrozole compared with mifepristone,pain relief was significantly（P0.05）.Escape responses were significantly decreased in letrozole rats who withstanded different vaginal pressures about 20,30,40 mmHg,less occurrence of hyperalgesia than the blank group（P0.05）.At 5,10 mmHg pressure,the escape rates were not statistically significant in each group（P0.05）.The expressions of TNF-α,IL-6,NF-κB protein and mRNA in ectopic endometrium of each treatment group,lower than those in the control group（P0.05）,especially high dose group was the lowest.The expression of NF-κB was positive correlation with the expression of TNF-α and IL-6,respectively.Conclusion：Letrozole significantly influences the size of ectopic lesions and relieved pain in rats,possibly through reducing the expression of TNF-α,IL-6,NF-κB in endometriotic tissues play a therapeutic role.