Senescence of osteocyte and dyamism of nuclear proteins

为了诱导细胞衰老，我们进行了完全无蛋白的肉瘤克隆培养。电镜和流式细胞术分析显示，生长的减少伴随着凋亡细胞的出现。然而，未观察到核小体间断裂。脉冲场凝胶电泳显示，在无蛋白细胞中发现DNA被切割成高分子量的片段，估计为50至150千碱基。Hoechst 33342流式细胞术显示大片段DNA与细胞凋亡直接相关。抑制剂分析表明细胞凋亡涉及一种特定的内源性核酸内切酶。另一方面，利用形态计量学对骨重塑的理论分析表明，所谓的骨质疏松症是由于骨的适应过程。在骨量有限的情况下，外径和内径的扩张优化了由面积和矩惯性计算的骨机械强度。

In order to induce cellular senescence, complete protein-free cuture of sarcoma clone was performed. Electron-microscopic and flow-cytometric analyzes revealed that the reduction in growth was accomanied by the appearance of apoptotic cells. However, no internucleosomal fragmentation was observed. Pulse field gel electrophoresis revealed that cleavage of DNA into high-molecular-weight fragments estimated as 50 to 150 kilobase was found in the protein-free cells. Flow cytometry using Hoechst 33342 showed a direct correlation between the large DNA fragmentation and apoptosis. Inhibitor analysis suggest that the apoptosis involves a specific endogenous endonuclease.On the other hand, theoretical analysis of bone remodeling using morphometry revealed that so-called osteoporosis is due to an adaptational process of bone. Under limited bone mass, expansion of external and internal diameters optimize bone mechanical strength calculated by area and moment inertia.