Laboratory of Molecular Toxicology, College of Pharmacy, Pusan National University, San 30, Jangjeon-dong, Geumjeung-gu, Busan 609-735, South Korea.
Arch Toxicol. 2011 Aug;85(8):975-85. doi: 10.1007/s00204-010-0618-5. Epub 2010 Nov 16.
This study was conducted to determine the functional role of phospholipase D (PLD) involved in testicular Leydig cell damage caused by di (2-ethylhexyl) phthalate (DEHP) in Sprague-Dawley rats. DEHP (500 mg/kg/day) was administered orally to prepubertal rats for 1, 7, 14, 21 or 28 days. After 7 days of exposure, DEHP produced morphological changes in the testis, including alterations in seminiferous tubule diameters and loss of spermatogenic cells. Immunohistochemistry (IHC) analyses revealed that DEHP increased Leydig cell number in the testes as well as significantly increased the expression of PLD1/2 in Leydig cells after 7 days of exposure. Furthermore, the protein levels of phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) increased in a similar manner to the PLD1/2 expression patterns. DEHP significantly reduced the expression of sperm-associated antigen 4 (Spag4) and lactate dehydrogenase A (LDHA) mRNA. In contrast, there was a significant increase in the expression of steroidogenic acute regulatory (StAR) mRNA against DEHP in a time-dependent manner, but serum testosterone concentration was decreased. These findings demonstrate that DEHP induces PLD expression in the testicular Leydig cells; this plays a key role in hyperplasia of Leydig cells and steroidogenic pathway via pERK1/2 activation.
本研究旨在确定磷脂酶 D (PLD) 在邻苯二甲酸二 (2-乙基己基) 酯 (DEHP) 引起的睾丸间质细胞损伤中的功能作用。DEHP（500 mg/kg/天）经口给予未成年大鼠 1、7、14、21 或 28 天。暴露 7 天后，DEHP 导致睾丸形态发生变化，包括曲细精管直径改变和生精细胞丢失。免疫组织化学 (IHC) 分析显示，DEHP 增加了睾丸间质细胞的数量，并且在暴露 7 天后，明显增加了 PLD1/2 在间质细胞中的表达。此外，磷酸化细胞外信号调节激酶 1/2（pERK1/2）的蛋白水平也以类似的方式增加，与 PLD1/2 的表达模式一致。DEHP 显著降低了精子相关抗原 4（Spag4）和乳酸脱氢酶 A（LDHA）mRNA 的表达。相反，StAR mRNA 的表达在时间上呈依赖性增加，但血清睾酮浓度降低。这些发现表明，DEHP 诱导睾丸间质细胞中 PLD 的表达；这在通过 pERK1/2 激活的间质细胞增生和类固醇生成途径中起关键作用。
