J Proteome Res：科学家解决吸烟弱化骨骼之谜

自科学​​家们首次发现吸烟为骨质疏松症和骨折的危险因素20年后，今日，一项新的研究阐明了香烟烟雾是如何削弱骨骼的。相关研究论文发表在Journal of Proteome Research研究杂志上，该研究报告得出结论认为香烟烟雾使人们产生促发身体自然存在的破骨行为的一种过量的蛋白质。

Gary Guishan Xiao和他的同事指出，以往的研究表明香烟烟雾中毒素通过影响成骨细胞削弱骨骼，成骨细胞主要用于建立新的骨细胞，破骨细胞主要用来打破老骨头。骨骼弱化称为骨质疏松症，可以增加骨折的风险，这是老年人残疾的主要原因。为了搞清楚吸烟削弱骨骼，科学家们分析了吸烟者和非吸烟者的骨髓细胞中的遗传基因活动的差异。
 
他们发现吸烟者体内产生非常大的两种蛋白质，促进破骨细胞的生产，其生成蛋白质的数量远远高于非吸烟者。这个结论在实验室老鼠实验中得到了证实。

编译自：Solving the Mystery of How Cigarette Smoking Weakens Bones

原文摘要：

Smoke-Induced Signal Molecules in Bone Marrow Cells from Altered Low-Density Lipoprotein Receptor-Related Protein 5 Mice

Danjun Ma, Yan Li, Bryan Hackfort, Yingchun Zhao, Jing Xiao, Patrick C. Swanson, Joan Lappe, Peng Xiao,et al.

Mechanism underlying smoke-induced loss of bone mass is unknown. In this study, we hypothesized that protein signals induced by smoking in bone marrow may be associated with the loss of bone mass. Using a proteomics approach, we identified 38 proteins differentially expressed in bone marrow cells from low-density lipoprotein receptor-related protein 5 (Lrp5) mice exposed to cigarette smoking. Smoking effects on protein expression in bone marrow among three genotypes (Lrp5+/+, Lrp5G171V, and Lrp5–/–) varied. On the basis of the ratio of protein expression induced by smoking versus nonsmoking, smoke induced protein expression significantly in wild-type mice compared to the other two genotypes (Lrp5G171V and Lrp5–/–). These proteins include inhibitors of β-catenin and proteins associated with differentiation of osteoclasts. We observed that S100A8 and S100A9 were overexpressed in human smokers compared to nonsmokers, which confirmed the effect of smoking on the expression of two proteins in Lrp5 mice, suggesting the role of these proteins in bone remodeling. Smoke induced expression of S100A8 and S100A9 in a time-dependent fashion, which was opposite of the changes in the ratio of OPG/RANKL in bone marrow cells, suggesting that the high levels of S100A8 and S100A9 may be associated with smoke-induced bone loss by increasing bone resorption.