Role of tumor necrosis factor-alpha and the modulating effect of the caspases in rat corpus luteum apoptosis
Role of tumor necrosis factor-alpha and the modulating effect of the caspases in rat corpus luteum apoptosis
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DOI：
10.1095/biolreprod.102.010819
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发表时间：
2003-04-01
影响因子：
3.6
通讯作者：
Dharmarajan, A
中科院分区：
文献类型：
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作者：
Abdo, M;Hisheh, S;Dharmarajan, A
肿瘤坏死因子-α（TNF α）是一种多效性细胞因子，其与许多细胞系统的凋亡有关。然而，在黄体（CL）的结构和功能退化过程中TNF α的信号转导在很大程度上是未知的。在这项研究中，我们研究了TNF α在大鼠CL凋亡中的作用，以及单核细胞趋化蛋白-1（MCP-1）的参与和caspase在此过程中的调节作用。使用免疫组织化学和蛋白质印迹分析在妊娠期间和产后进行的CL体内研究表明，TNF α的增加与接近足月（第22天）和产后（第3天）的黄体细胞凋亡相对应。CL细胞凋亡进一步研究使用全CL培养模型的热带退缩。从0 h到8 h，在培养物中观察到低分子量（MW）DNA断裂和TUNEL染色增加。通过免疫组化和Western印迹分析，体外CL凋亡与TNF α和MCPA蛋白表达增加相关。使用全CL。培养模型中，TNF α在体外诱导细胞凋亡，如DNA片段化的剂量依赖性增加所证明的。用TNF α和两种特异性半胱天冬酶抑制剂（Z-DEVD-FMK、Z-VEID-FMK、Z-IETD-FMK）或一般半胱天冬酶抑制剂（Boc-D-FMK）处理黄体细胞可阻止TNF α的作用。CL消退涉及黄体细胞的凋亡缺失;本研究的结果表明TNF α可能参与了这一过程。所观察到的MCP-1表达的增加表明TNF α表达与巨噬细胞的浸润和活化相协调。此外，结果证明了caspase在TNF α信号转导途径中的重要性，并表明了caspase家族内的层次结构。
Tumor necrosis factor-alpha (TNFalpha) is a pleiotropic cytokine that has been implicated in apoptosis of many cell systems. However, the signal transduction of TNFalpha during the structural and functional regression of the corpus luteum (CL) is largely unknown. In this study, we investigate the role of TNFalpha in rat CL apoptosis and the involvement of monocyte chemoattractant protein-1 (MCP-1) and the modulating effect of the caspases in this process. An in vivo study of CL during pregnancy and postpartum using immunohistochemistry and Western blot analysis indicated that increases in TNFalpha correspond with luteal apoptosis approaching term (Day 22) and at postpartum (Day 3). CL apoptosis was further investigated using a whole-CL culture model of tropic withdrawal. An increase was observed in both low molecular weight (MW) DNA fragmentation and TUNEL staining from 0 h to 8 h in culture. CL apoptosis in vitro was associated with increased protein expression of both TNFalpha and MCPA as measured by immunohistochemistry and Western blot analysis. Using a whole-CL. culture model, apoptosis was induced in vitro by TNFalpha as demonstrated by a dose-dependent increase in DNA fragmentation. Treatment of luteal cells with TNFalpha and both specific caspase inhibitors (Z-DEVD-FMK, Z-VEID-FMK, Z-IETD-FMK) or a general caspase inhibitor (Boc-D-FMK) prevented the effect of TNFalpha. CL regression involves the apoptotic deletion of luteal cells; the results of this study suggest that TNFalpha is possibly involved in this process. The observed increases in MCP-1 expression suggest the coordination of TNFalpha expression with the infiltration and activation of macrophages. Furthermore, the results demonstrate the importance of the caspases in the TNFalpha signal transduction pathway and suggest a hierarchy within the caspase family.