细胞渗透性神经酰胺可抑制大鼠离体黄体细胞甾体激素生成并诱导细胞凋亡(英文)

Inhibition of steroidogenesis and induction of apoptosis in rat luteal cells by cell-permeable ceramide in vitro

本文旨在观察神经酰胺对离体孵育的大鼠黄体细胞孕酮分泌及细胞凋亡的影响。以PMSG hCG处理的雌性Wistar大鼠为模型 ,分离制备黄体细胞。将外源性细胞渗透性神经酰胺与黄体细胞共同孵育 ,分别用放免法和流式细胞仪分析神经酰胺对黄体细胞孕酮生成和凋亡的影响 ,同时还检测了一氧化氮合酶 (NOS)活性和一氧化氮(NO)水平的变化。结果显示 ,神经酰胺可以剂量相关方式抑制hCG 诱导的孕酮分泌 ,而对基础孕酮没有显著影响。离体孵育 12h的大鼠黄体细胞存在自发性凋亡 ,5 μmol/L神经酰胺能显著增加凋亡率 (P <0 0 5 ) ,流式细胞仪分析可见增强的凋亡峰。实验还发现 ,5 0 μmol/L神经酰胺能明显促进NOS活性 (P <0 0 1)和NO生成 (P <0 0 0 1)。结果提示 ,神经酰胺可能通过调节甾体激素生成和细胞凋亡而作为一种重要的信息分子参与黄体退化等卵巢的生理过程。

WT5”BZ] The present study was undertaken to investigate the effects of ceramide on progesterone production and apoptosis in rat luteal cells in vitro . Luteal cells were prepared from the ovaries of pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) primed female Wistar rats and incubated with cell permeable C2 ceramide. The effects of ceramide on progesterone production and apoptosis in luteal cells were assessed by radio immunoassay (RIA) and flow cytometry analysis. In addition, changes in nitric oxide synthase (NOS) activity and nitric oxide (NO) production by luteal cells treated with C2 ceramide were also evaluated. Ceramide was found to reduce hCG stimulated progesterone production in a dose dependent manner, whereas it had little effect on basal progesterone content. Spontaneous apoptosis in luteal cells was observed after a 12 hour incubation in vitro and 5 μmol/L of ceramide significantly increased the apoptotic rate ( P <0 05). Enhanced apoptotic peak was seen in the histogram by flow cytometry. Moreover, 50 μmol/L of C2 ceramide significantly increased NOS activity ( P <0 01) and NO production ( P <0 001). It is suggested that ceramide may serve as an important signaling molecule mediating certain ovarian processes, such as luteal regression.