Department of Physiology, Medical College of Nanchang University, Nanchang, People's Republic of China.
Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang, People's Republic of China.
Reproduction. 2019 Jul;158(1):61-69. doi: 10.1530/REP-18-0456.
Tri-ortho-cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners and flame-retardants in industry and reported to have male reproductive toxicology. However, it is still unknown whether TOCP affects the female reproductive system and its underlying mechanism. In the present study, we found that TOCP exposure significantly decreased ovarian coefficient, caused disintegration and depletion of the granulosa cells in the ovary tissue and significantly inhibited the level of serum estradiol (E2). TOCP markedly increased both LC3-II and the ratio of LC3-II/LC3-I as well as autophagy proteins ATG5 and Beclin1 in the ovary tissue, implying that TOCP could induce autophagy in the ovary tissue. To further investigate the potential mechanism, primary ovarian granulosa cells were isolated in vitro and treated with 0-0.5 mM TOCP for 48 h. We showed that TOCP decreased the number of viable mouse granulosa cells without affecting cell cycle and apoptosis of the cells. Intriguingly, TOCP treatment markedly increased both LC3-II and the ratio of LC3-II/LC3-I as well as ATG5 and Beclin1. Furthermore, transmission electron microscopy (TEM) showed that autophagic vesicles in the cytoplasm increased significantly in the TOCP-treated cells, indicating that TOCP could induce autophagy in the cells. Taken together, TOCP reduces the number of viable cells and induces autophagy in mouse ovarian granulosa cells without affecting cell cycle and apoptosis.
三邻甲苯磷酸酯(TOCP)在工业中被广泛用作增塑剂、增塑软化剂和阻燃剂,并有报道称其具有雄性生殖毒性。然而,目前尚不清楚 TOCP 是否会影响女性生殖系统及其潜在机制。在本研究中,我们发现 TOCP 暴露可显著降低卵巢系数,导致卵巢组织中颗粒细胞解体和耗竭,并显著抑制血清雌二醇(E2)水平。TOCP 可显著增加卵巢组织中 LC3-II 和 LC3-II/LC3-I 的比值以及自噬蛋白 ATG5 和 Beclin1,表明 TOCP 可诱导卵巢组织自噬。为了进一步探讨潜在的机制,我们在体外分离了原代卵巢颗粒细胞,并在 0-0.5mM TOCP 处理 48 小时。我们发现 TOCP 可减少活的小鼠颗粒细胞数量,而不影响细胞周期和细胞凋亡。有趣的是,TOCP 处理可显著增加 LC3-II 和 LC3-II/LC3-I 的比值以及 ATG5 和 Beclin1。此外,透射电子显微镜(TEM)显示,TOCP 处理的细胞中细胞质中的自噬小泡明显增加,表明 TOCP 可诱导细胞自噬。综上所述,TOCP 可减少活细胞数量,并在不影响细胞周期和凋亡的情况下诱导小鼠卵巢颗粒细胞自噬。