Ding Si-Min, Shi Ling-Ge, Cao Zhen-Ping, Zhu Na-Na, Liu Yun-Yun, Wang Meng-Yao, Cui Shuang-Shuang, Cheng Hui-Ru, Liang Dan, Cao Yun-Xia, Liu Ya-Jing
Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China.
NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230022, China.
Heliyon. 2024 Jun 17;10(12):e33132. doi: 10.1016/j.heliyon.2024.e33132. eCollection 2024 Jun 30.
Previous studies have shown that serotonin and its receptors are widely distributed in mammalian reproductive tisssues and play an important role in embryonic development. However, the specific effects of the serotonergic system on embryonic arrest (EA) and the underlying mechanism require further investigation.
Chorionic villi were collected from patients with EA and healthy pregnant women. Western blotting (WB) and immunohistochemistry (IHC) were used to detect serotonin receptor 1B (HTR1B) levels and evaluate mitochondrial function. Additionally, HTR-8/SVneo cells were transfected with an HTR1B overexpression plasmid. Quantitative real-time polymerase chain reaction(qRT-PCR), Cell Counting Kit-8 (CCK-8), and wound healing assays were utilized to evaluate mitophagy level, cell proliferation and cell migration, respectively.
We discovered elevated HTR1B levels in the chorionic villi of the patients with EA compared to controls. Concurrently, we observed enhanced levels of nucleus-encoded proteins including mitofilin, succinate dehydrogenase complex subunit A (SDHA), and cytochrome oxidase subunit 4 (COXIV), along with the mitochondrial fusion protein optic atrophy 1(OPA1), fission proteins mitochondrial fission protein 1(FIS1) and mitochondrial fission factor (MFF) in the EA group. Additionally, there was an excessive mitophagy levels in EA group. Furthermore, a notable activation of mitogen-activated protein kinase (MAPK) signaling pathway proteins including extracellular regulating kinase (ERK), c-Jun N-terminal kinase (JNK), and P38 was observed in the EA group. By overexpressing HTR1B in HTR-8/SVneo cells, we observed a significant reduction in cell proliferation and migration. HTR1B overexpression also caused an increase in levels of SDHA and FIS1, as well as an upregulation of mitophagy. Notably, the ERK inhibitor U0126 effectively mitigated these effects.
These findings show that HTR1B influences mitochondrial homeostasis, promoting excessive mitophagy and impairing cell proliferation and migration by activating the MAPK signalling pathway during post-implantation EA. Therefore, HTR1B may serve as a potential therapeutic target for patients with EA.
先前的研究表明，血清素及其受体广泛分布于哺乳动物生殖组织中，并在胚胎发育中发挥重要作用。然而，血清素能系统对胚胎停育（EA）的具体影响及其潜在机制仍需进一步研究。
收集EA患者和健康孕妇的绒毛膜绒毛。采用蛋白质免疫印迹法（WB）和免疫组织化学法（IHC）检测血清素受体1B（HTR1B）水平并评估线粒体功能。此外，用HTR1B过表达质粒转染HTR-8/SVneo细胞。分别采用定量实时聚合酶链反应（qRT-PCR）、细胞计数试剂盒-8（CCK-8）和伤口愈合试验评估线粒体自噬水平、细胞增殖和细胞迁移。
我们发现，与对照组相比，EA患者绒毛膜绒毛中的HTR1B水平升高。同时，我们观察到EA组中包括线粒体内膜嵴连接蛋白、琥珀酸脱氢酶复合物亚基A（SDHA）和细胞色素氧化酶亚基4（COXIV）在内的核编码蛋白水平升高，以及线粒体融合蛋白视神经萎缩蛋白1（OPA1）、分裂蛋白线粒体分裂蛋白1（FIS1）和线粒体分裂因子（MFF）水平升高。此外，EA组存在过度的线粒体自噬水平。此外，在EA组中观察到丝裂原活化蛋白激酶（MAPK）信号通路蛋白包括细胞外调节激酶（ERK）、c-Jun氨基末端激酶（JNK）和P38的显著激活。通过在HTR-8/SVneo细胞中过表达HTR1B，我们观察到细胞增殖和迁移显著减少。HTR1B过表达还导致SDHA和FIS水平升高，以及线粒体自噬上调。值得注意的是，ERK抑制剂U0126有效地减轻了这些影响。
这些发现表明，HTR1B影响线粒体稳态，在着床后EA期间通过激活MAPK信号通路促进过度的线粒体自噬并损害细胞增殖和迁移。因此，HTR1B可能是EA患者的潜在治疗靶点。
