Zhao Yan, Zhao Xiaoxuan, Feng Xiaoling
Department of Gynecology, The First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, 150040, China.
Department of Traditional Chinese Medicine (TCM) Gynecology, Hangzhou Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Hangzhou, 310007, China.
Open Med (Wars). 2024 Jun 5;19(1):20240963. doi: 10.1515/med-2024-0963. eCollection 2024.
With unknown etiology and limited treatment options, unexplained recurrent pregnancy loss (URPL) remains a thorny problem. Ferroptosis, a newly identified type of cell death, has been shown to be crucial in the development in reproductive disorders. This study aims to explore the specific mechanism of ferroptosis in URPL and to uncover whether alpha-lipoic acid (ALA) can inhibit ferroptosis, and then exert a protective effect in URPL.
The decidua tissues of URPL and control patients who actively terminated pregnancy were collected. The CBA/J × DBA/2 murine models of URPL were established, and were randomly treated with peroxisome proliferator activated receptor γ (PPARγ) agonists (Rosiglitazone) and ALA. The CBA/J × BALB/c murine models of normal pregnancy were intraperitoneally injected with PPARγ inhibitors (T0070907). Here, we used reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH)/GSSG, and FeRhoNox-1 analysis to detect the level of ferroptosis. We used quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) analysis to evaluate the mRNA level of PPARγ. Besides, western blot and immunofluorescence were utilized to test the expression profile of PPARγ/nuclear factor erythroid 2-related factor 2 (NRF2)/glutathione peroxidase 4 (GPX4).
In this study, we found that iron deposition was increased in the decidual tissue of patients with URPL. Additionally, the changes in cell morphology, the level of ROS, MDA, GSH, and the expression of ferroptosis marker proteins NRF2/GPX4 confirmed activated ferroptosis in URPL. Besides, bioinformatics analysis combined with experiments confirmed that PPARγ was critical in triggering NRF2/GPX4 pathway in URPL. Furthermore, URPL mouse models were established, and the results showed that PPARγ/NRF2/GPX4-mediated ferroptosis was also significantly increased, which could be mitigated by ALA treatment.
Overall, these findings suggest that ferroptosis may play an important role in URPL, and ALA might be a promising therapeutic drug for improving pregnancy outcomes in URPL via targeting the PPARγ/NRF2/GPX4 pathway.
不明原因复发性流产（URPL）病因不明且治疗选择有限，仍然是一个棘手的问题。铁死亡是一种新发现的细胞死亡类型，已被证明在生殖系统疾病的发展中起关键作用。本研究旨在探讨铁死亡在URPL中的具体机制，并揭示α-硫辛酸（ALA）是否能抑制铁死亡，进而在URPL中发挥保护作用。
收集URPL患者及主动终止妊娠的对照患者的蜕膜组织。建立URPL的CBA/J×DBA/2小鼠模型，并随机用过氧化物酶体增殖物激活受体γ（PPARγ）激动剂（罗格列酮）和ALA进行处理。对正常妊娠的CBA/J×BALB/c小鼠模型腹腔注射PPARγ抑制剂（T0070907）。在此，我们使用活性氧（ROS）、丙二醛（MDA）、谷胱甘肽（GSH）/氧化型谷胱甘肽（GSSG）以及FeRhoNox-1分析来检测铁死亡水平。我们使用定量实时逆转录聚合酶链反应（qRT-PCR）分析来评估PPARγ的mRNA水平。此外，采用蛋白质印迹法和免疫荧光法检测PPARγ/核因子红细胞2相关因子2（NRF2）/谷胱甘肽过氧化物酶4（GPX4）的表达情况。
在本研究中，我们发现URPL患者蜕膜组织中铁沉积增加。此外，细胞形态的变化、ROS、MDA、GSH水平以及铁死亡标记蛋白NRF2/GPX4的表达证实了URPL中铁死亡被激活。此外，生物信息学分析结合实验证实PPARγ在触发URPL中的NRF2/GPX4通路中起关键作用。此外，建立了URPL小鼠模型，结果表明PPARγ/NRF2/GPX4介导的铁死亡也显著增加，而ALA处理可减轻这种情况。
总体而言，这些发现表明铁死亡可能在URPL中起重要作用，并且ALA可能是一种有前景的治疗药物，通过靶向PPARγ/NRF2/GPX4通路改善URPL的妊娠结局。
