Lin Yi-feng, Zhang Nong, Guo Hong-shen, Kong De-sheng, Jiang Tao, Liang Wang, Zhao Zhong-hua, Tang Qi-qun, Ma Duan
Department of Pathology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
Apoptosis. 2007 Dec;12(12):2163-73. doi: 10.1007/s10495-007-0136-y.
Tissue factor pathway inhibitor (TFPI) is an endogenous inhibitor of tissue factor (TF) induced coagulation. In addition to its anticoagulation activity, TFPI has other functions such as antiproliferation and inducing apoptosis. In the present study, we investigated whether or not TFPI induced apoptosis in cultured rat mesangial cells (MsCs) and the possible signal pathway that involved in the apoptotic process. We demonstrated that recombinant TFPI (rTFPI) induced apoptosis in cultured MsCs via its Kunitz-3 domain and C-terminal in a dose- and time-dependent manner by Hoechst 33258 assay, flow cytometry, nucleosomal laddering of DNA, caspase 3 assay. Because the serine/threonine protein kinase Akt has attracted attention as a mediator of survival (anti-apoptotic) signal in MsCs, we investigated the expression of phosphospecific-Akt and its downstream signal phospho-IkappaB-alpha and some other signal molecules like Fas and bcl-2. The results indicated that the process of apoptosis triggered by rTFPI is, at least in part, actively conducted by rat MsCs possibly through PI3-Kinase-Akt signal pathway not by binding to tissue factor. Our findings suggest that rTFPI has the potential usefulness in inducing apoptosis of MsCs under inflammatory conditions.
组织因子途径抑制剂（TFPI）是一种组织因子（TF）诱导凝血的内源性抑制剂。除了其抗凝活性外，TFPI还具有其他功能，如抗增殖和诱导细胞凋亡。在本研究中，我们调查了TFPI是否能诱导培养的大鼠系膜细胞（MsCs）凋亡以及凋亡过程中可能涉及的信号通路。通过Hoechst 33258检测、流式细胞术、DNA核小体梯状条带分析、半胱天冬酶3检测，我们证明重组TFPI（rTFPI）通过其Kunitz-3结构域和C末端以剂量和时间依赖性方式诱导培养的MsCs凋亡。由于丝氨酸/苏氨酸蛋白激酶Akt作为MsCs中存活（抗凋亡）信号的介质受到关注，我们研究了磷酸化特异性Akt及其下游信号磷酸化IκB-α以及其他一些信号分子如Fas和bcl-2的表达。结果表明，rTFPI触发的凋亡过程至少部分是由大鼠MsCs通过PI3-激酶-Akt信号通路主动进行的，而不是通过与组织因子结合。我们的研究结果表明，rTFPI在炎症条件下诱导MsCs凋亡方面具有潜在的应用价值。
