通过诱导睾丸Leydig细胞铁凋亡加重镉降低的睾酮水平

Plin4 exacerbates cadmium-decreased testosterone level via inducing ferroptosis in testicular Leydig cells

通过诱导睾丸Leydig细胞铁凋亡加重镉降低的睾酮水平

Authors: Zhang XD, Sun J, Zheng XM, Zhang J, Tan LL, Fan LL, Luo YX, Hu YF, Xu SD, Zhou H, Zhang YF, Li H, Yuan Z, Wei T, Zhu HL, Xu DX, Xiong YW, Wang H.

Source：Redox Biol. 2024 Aug 17;76:103312. doi: 10.1016/j.redox.2024.103312.

Abstract

Strong evidence indicates that environmental stressors are the risk factors for male testosterone deficiency (TD). However, the mechanisms of environmental stress-induced TD remain unclear. Based on our all-cause male reproductive cohort, we found that serum ferrous iron (Fe2⁺) levels were elevated in TD donors. Then, we explored the role and mechanism of ferroptosis in environmental stress-reduced testosterone levels through in vivo and in vitro models. Data demonstrated that ferroptosis and lipid droplet deposition were observed in environmental stress-exposed testicular Leydig cells. Pretreatment with ferrostatin-1 (Fer-1), a specific ferroptosis inhibitor, markedly mitigated environmental stress-reduced testosterone levels. Through screening of core genes involved in lipid droplets formation, it was found that environmental stress significantly increased the levels of perilipins 4 (PLIN4) protein and mRNA in testicular Leydig cells. Further experiments showed that Plin4 siRNA reversed environmental stress-induced lipid droplet deposition and ferroptosis in Leydig cells. Additionally, environmental stress increased the levels of METTL3, METTL14, and total RNA m6A in testicular Leydig cells. Mechanistically, S-adenosylhomocysteine, an inhibitor of METTL3 and METTL14 heterodimer activity, restored the abnormal levels of Plin4, Fe2⁺ and testosterone in environmental stress-treated Leydig cells. Collectively, these results suggest that Plin4 exacerbates environmental stress-decreased testosterone level via inducing ferroptosis in testicular Leydig cells.

Keywords：Environment stress; Ferroptosis; Lipid droplet; Perilipins; Testosterone deficiency; m6A modification.

摘要

强有力的证据表明，环境压力是男性睾酮缺乏症（TD）的危险因素。然而，环境胁迫诱导TD的机制仍不清楚。基于我们的全因男性生殖队列，我们发现血清亚铁（Fe2+）水平升高TD捐助者。然后，我们通过体内和体外模型，探讨了铁凋亡在环境应激降低睾酮水平中的作用和机制。结果表明，环境应激后睾丸间质细胞出现铁凋亡和脂滴沉积。预处理与ferrostatin-1（Fer-1），一个特定的ferroptosis抑制剂，显着减轻环境压力降低睾酮水平。通过筛选与脂滴形成相关的核心基因，发现环境应激显著增加睾丸Leydig细胞中围脂蛋白4（perilipins 4，PLIN 4）蛋白和mRNA的水平。进一步的实验表明，Plin 4 siRNA逆转了环境应激诱导的Leydig细胞中的脂滴沉积和铁凋亡。此外，环境应激增加睾丸Leydig细胞中的肌L3、肌L14和总RNA m6 A的水平。从机制上讲，S-腺苷高半胱氨酸，一种抑制剂的胃L3和胃L14异二聚体的活动，恢复异常水平的Plin 4，铁2β和睾酮在环境应激处理的Leydig细胞。总的来说，这些结果表明，Plin 4通过诱导睾丸间质细胞中的铁凋亡来加剧环境应激降低的睾酮水平。

关键词：环境应激;铁缺乏症;脂滴;周磷脂;睾酮缺乏症; m6 A修饰