An inverse relationship between bone marrow (BM) adiposity and bone mass has been described in different physiological and pathological conditions, including osteoporosis (OP). In osteoporotic patients, lower bone mass density is indeed associated with higher BM fat content, suggesting a potential role for bone lipids in the OP pathogenesis. Nevertheless, some questions remain. Is that BM adiposity a cause or a consequence of the bone loss? What kinds of lipids are involved? Human data are somehow contradictories regarding bone lipid signature related to OP, and animal data are needed to support on one or another way the human observations. Bone lipid signature associated to OP needs to be clarified if we want to understand better their roles in OP.

In that context, by using an ovariectomy-induced OP murine model and looking at lipids in two bone compartments: BM and mineralized tissue (MT), our first challenge was to identify local lipid changes in relation to OP, in view to explore later the mechanisms by which those compounds could alter bone quality, particularly during the mineralization process. As the most striking data, long-term OP resulted in an accumulation of triglycerides, reduced levels of arachidonic and docosahexaenoic acids, an increase of stearoyl-CoA desaturase indices and a reduction of sphingomyelin in the MT, and potential consequences on bone properties and cell activities are discussed. The reader will appreciate that we are at an early stage of understanding the roles of lipids in the OP development and more investigations will be necessary.

已经在包括骨质疏松症（OP）在内的不同生理和病理条件下描述了骨髓（BM）肥胖与骨量之间的反比关系。在骨质疏松症患者中，较低的骨质密度确实与较高的BM脂肪含量有关，提示骨脂质在OP发病机理中具有潜在作用。但是，仍然存在一些问题。BM肥胖是骨丢失的原因还是后果？涉及哪些脂质？人类数据在某种程度上与与OP相关的骨脂质签名矛盾，因此需要动物数据来支持人类观察的一种或另一种方式。如果我们想更好地了解它们在OP中的作用，则需要澄清与OP相关的骨脂标记。

在这种情况下，通过使用卵巢切除术诱发的OP鼠模型并查看BM和矿化组织（MT）这两个骨腔中的脂质，我们的第一个挑战是确定与OP相关的局部脂质变化，以期以后探索这些化合物可以改变骨骼质量的机制，特别是在矿化过程中。作为最引人注目的数据，长期OP导致甘油三酸酯积聚，花生四烯酸和二十二碳六烯酸水平降低，硬脂酰-CoA去饱和酶指数增加以及MT中鞘磷脂的减少，以及对骨特性和细胞的潜在影响活动进行了讨论。读者将欣赏到我们还处于了解脂质在OP发展中的作用的早期阶段，因此有必要进行更多研究。