TLRs在中药治疗睾丸急性辐射损伤致生精功能障碍中的表达及调控机制研究

Large dose of radiation induces damages of spermatogenic cells, Sertoli cells and Leydig cells, which decrease spermatogenic function, and then, leads to reproductive disorder. Yet by now, there hasno effective medicine. Thus navy soldiers’mental and physical health would be seriously affected. Therefore, it is an emergent necessary for us to apply navy soldiers a safe and effective medicine to treat testicular radiation injury. So, we must first make clear some key scientific problems such as the mechanisms of testicular radiation injury, and the effective mechanisms of Chinese herbs in the repair of radiation injury. When there is inflammation, apoptotic spermatogenic cellsactivate TLRs to express in Sertoli cells and Leydig cells, which further decreased spermatogenesis. But in radiation injury, the expression of TLRs and their regulatory relationship among the above three cells remain to be unclarified. Consequently, this project plan to combine traditional Chinese medicine with radiology so as to explore the following issues, when radiation injury happens, TLRs expression in Sertoli cells and Leydig cells, regulators involved in TLRs expression, the effects on spermatogenic function, and the effects and mechanisms of radiation protective Chinese herbs are also to be studied. This project will supply technical supplies and theoretical basement for the research of testicularradiation injury mechanism, and the use of Chinese medicine in radiation injury protection. This project will supply the navy a safe and effective radiation protector, and will provide a foundation for the study of safe and effective radiation protection applied for ordinary people as well.

大剂量电离辐射致睾丸生精细胞、Sertoli细胞、Leydig细胞损伤，使生精功能受损，引发生殖障碍，现无有效治疗药物，这将严重影响舰艇海军官兵的身心健康。故研发安全可靠的睾丸急性辐射损伤治疗药物，是解决海军生理和心理障碍及顾虑，提高其作业和战斗力的迫切之需。为此，首先要明确睾丸辐射损伤机制等关键科学问题。炎症反应发生时，凋亡的生精细胞通过激活Sertoli、Leydig细胞的TLRs表达，进一步影响生精功能。但辐射损伤时TLRs的表达及在上述三种细胞间的调控关系不明。本项目拟结合中医药学与放射医学，研究辐射损伤时，TLRs在Sertoli、Leydig细胞的表达，参与TLRs表达的调控因子，对生精细胞功能的影响，及中药的治疗机制。本项目将为睾丸辐射损伤的机制研究和中医药治疗提供技术支持与理论依据；为海军提供安全可靠的防辐射健康促进措施；也为用于民众的安全有效辐射防治药研究提供基础。

本课题采用BALB/c小鼠和GC-2spd精母细胞株建立辐射损伤模型，研究电离辐射对雄性生殖系统的损伤效应，筛选并确定了益气解毒中药复方最佳给药剂量和给药时间。通过检测小鼠体重，脏器指数，全血细胞，精子质量，生育功能等，研究中药复方对生精功能辐射损伤的整体防护作用；聚焦天然免疫受体TLRs及其下游NF-κB通路，分析相关因子的表达，探究辐射损伤时中药复方对通路的影响。 .研究表明：（1）体内实验；60Coγ射线照射后，小鼠睾丸结构受损严重，生精细胞大量凋亡坏死，生精功能收损，精子活力及活率降低，造成生育功能障碍；益气解毒方可有效减轻电离辐射对小鼠睾丸的损伤以及保护其生精功能。（2）体外实验：电离辐射造成生精细胞DNA双链断裂，氧化应激损伤和炎症反应；益气解毒方可以从抗氧化、促进DNA损伤修复、调控炎症反应等方面抑制辐射后生精细胞的损伤和凋亡。（3）机制方面：辐射后小鼠睾丸中生精细胞和支持细胞中TLR4/TLR5/MyD88/NF-κB的表达发生改变，而中药复方可在一定程度上调控TLR4/TLR5/MyD88/NF-κB通路的表达；电离辐射后小鼠精子中TLR5、GSK-3α表达发生改变，益气解毒方可通过修复附睾微环境的损伤以下调TLR5、GSK-3α在精子上的表达，继而提高小鼠生育力；电离辐射诱导生精细胞IκBα/NF-κB信号通路活化，可能通过调节Beclin-1和Bcl-2因子的表达，发挥促自噬和凋亡的作用，益气解毒方作用于NF-κB通过抑制IκBα/NF-κB信号通路活化，进而调节Beclin-1和Bcl-2的表达，发挥了抑制自噬体大量合成和抗凋亡的作用。研究结果证明了益气解毒方可以从多靶点发挥防治雄性生殖功能损伤的作用。.此研究结果有助于进一步了解电离辐射造成生精功能损伤的机制，也为中医药防护急性辐射损伤的研究提供可供参考的研究思路和方法。