17β-雌二醇通过Bad介导的信号通路抑制人髓核细胞凋亡的作用机制研究

The incidence of intervertebral disc degenerative diseases is increasing annually, which has been a serious medical problem in modern society. It has been previously reported that aberrant apoptosis of nucleus pulposus cells is a key cellular process in intervertebral disc degeneration (IVDD), which is closely related to oxidative stress. In previous in-vitro studies, we have preliminarily proved that 17beta-estradiol inhibited aberrant apoptosis by upregulating integrin α2β1 and downregulating MMP-3 and MMP-13 in rat nucleus pulposus cells. Our recent pilot study showed that 17beta-estradiol protected human nucleus pulposus cells against apoptosis induced by oxidative stress by activating Bad/Cyt C/caspase-3 pathway. Taken together, in this study we will further explore the protective effect of 17beta-estradiol on human nucleus pulposus cells against apoptosis induced by oxidative stress, focusing on Bad-mediated upstream signal pathways including PKA/Bad pathway, Akt/Bad pathway, and ERK1/2/Bad pathway. All experiments are based on apoptotic cell model induced by H2O2, and multiple mature experimental methods are used, including IHC, FACS analysis, TUNEL, western blot and real-time quantitative PCR. Meanwhile, the inhibitors of signal pathways are used to further verify the involved mechanism. This study is designed to provide solid theoretical basis for the use of estrogen to retard IVDD in the future.

椎间盘退变性疾病的发病率逐年上升，已成为当代社会严重的医疗问题。既往研究认为髓核细胞异常凋亡是椎间盘退变的主要细胞学进程，且与氧化应激密切相关。在前期的离体研究中，我们发现17β雌二醇通过上调整联蛋白α2β1和下调MMP-3、MMP-13的表达抑制髓核细胞的异常凋亡。而近期的预实验显示17β-雌二醇通过激活Bad/Cyt C/caspase-3通路抑制氧化应激诱导的人髓核细胞的凋亡。本课题拟采用IHC、FACS、TUNEL、Western blot、Real-time qPCR等多种成熟技术，应用H2O2诱导的细胞凋亡模型，进一步探索17β-雌二醇对氧化应激诱导的人髓核细胞的凋亡抑制作用，并重点研究Bad介导的上游信号通路，包括PKA/Bad途径、Akt/Bad途径和ERK1/2/Bad途径，同时应用信号通路抑制剂从反面验证。本课题为将来应用雌激素延缓椎间盘退变进程提供一定的理论依据。

椎间盘退变性疾病的发病率逐年上升，已成为当代社会严重的医疗问题。既往研究认为髓核细胞异常凋亡是椎间盘退变的主要细胞学进程，且与氧化应激密切相关。本课题组一直从事雌激素抗椎间盘细胞凋亡的实验研究。本课题采用IHC、FACS、TUNEL、Western blot、Real-time qPCR等多种成熟技术，应用过氧化氢诱导的细胞凋亡模型，实验结果显示，17β-雌二醇通过激活Bad/Cyt C/caspase-3通路抑制氧化应激诱导的人髓核细胞的凋亡。我们进一步探索17β-雌二醇对氧化应激诱导的人髓核细胞的凋亡抑制作用，并重点研究Bad介导的上游信号通路，包括PKA/Bad途径、Akt/Bad途径和ERK1/2/Bad途径，同时应用信号通路抑制剂从反面验证。最终发现，17β-雌二醇通过激活Akt/Bad途径和ERK1/2/Bad途径抑制过氧化氢的氧化应激作用诱导的人髓核细胞的凋亡。本课题实验研究结果已经发表3篇SCI收录的英文论文，尚有重要研究结果待整理发表。本课题研究结果旨在为将来应用雌激素延缓椎间盘退变进程提供一定的理论依据。