Background Osteoporosis often occurs with carotid atherosclerosis and causes contradictory calcification across tissue in the same patient, which is called the "calcification paradox". Circulating monocytes may be responsible for this unbalanced ectopic calcification. Here, we aimed to show how CD14+ monocytes contribute to the pathophysiology of coexisting postmenopausal osteoporosis and carotid atherosclerosis. Methods We comprehensively analyzed osteoporosis data from the mRNA array dataset GSE56814 and the scRNA-seq dataset GSM4423510. Carotid atherosclerosis data were obtained from the GSE23746 mRNA dataset and GSM4705591 scRNA-seq dataset. First, osteoblast and vascular SMC lineages were annotated based on their functional expression using gene set enrichment analysis and AUCell scoring. Next, pseudotime analysis was applied to draw their differentiated trajectory and identify the key gene expression changes in crossroads. Then, ligand-receptor interactions between CD14+ monocytes and osteoblast and vascular smooth muscle cell (SMC) lineages were annotated with iTALK. Finally, we selected calcification paradox-related expression in circulating monocytes with LASSO analysis. Results First, we found a large proportion of delayed premature osteoblasts in osteoporosis and osteogenic SMCs in atherosclerosis. Second, CD14+ monocytes interacted with the intermediate cells of the premature osteoblast and osteogenic SMC lineage by delivering TGFB1 and TNFSF10. This interaction served as a trigger activating the transcription factors (TF) SP1 and NFKB1 to upregulate the inflammatory response and cell senescence and led to a retarded premature state in the osteoblast lineage and osteogenic transition in the SMC lineage. Then, 76.49% of common monocyte markers were upregulated in the circulating monocytes between the two diseases, which were related to chemotaxis and inflammatory responses. Finally, we identified 7 calcification paradox-related genes on circulating monocytes, which were upregulated in aging cells and downregulated in DNA repair cells, indicating that the aging monocytes contributed to the development of the two diseases. Conclusions Our work provides a perspective for understanding the triggering roles of CD14+ monocytes in the development of the calcification paradox in osteoporosis- and atherosclerosis-related cells based on combined scRNA and mRNA data. This study provided us with an elucidation of the mechanisms underlying the calcification paradox and could help in developing preventive and therapeutic strategies.

中文翻译：

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循环单核细胞通过 TGFB1-SP1 和 TNFSF10-NFKB1 轴作为骨质疏松症和颈动脉粥样硬化钙化悖论的常见触发因素。


背景 骨质疏松症常与颈动脉粥样硬化同时发生，并导致同一患者体内组织间出现矛盾的钙化，称为“钙化悖论”。循环单核细胞可能是造成这种不平衡的异位钙化的原因。在这里，我们的目的是展示 CD14+ 单核细胞如何促进共存的绝经后骨质疏松症和颈动脉粥样硬化的病理生理学。方法我们综合分析了 mRNA 阵列数据集 GSE56814 和 scRNA-seq 数据集 GSM4423510 的骨质疏松数据。颈动脉粥样硬化数据从 GSE23746 mRNA 数据集和 GSM4705591 scRNA-seq 数据集获得。首先，使用基因集富集分析和 AUCell 评分根据成骨细胞和血管 SMC 谱系的功能表达对其进行注释。接下来，应用伪时间分析来绘制它们的分化轨迹并识别十字路口的关键基因表达变化。然后，用 iTALK 注释 CD14+ 单核细胞与成骨细胞和血管平滑肌细胞 (SMC) 谱系之间的配体-受体相互作用。最后，我们通过 LASSO 分析选择了循环单核细胞中钙化悖论相关的表达。结果首先，我们在骨质疏松症中发现了很大比例的迟发性过早成骨细胞，在动脉粥样硬化症中发现了很大比例的成骨SMC。其次，CD14+单核细胞通过传递TGFB1和TNFSF10与过早成骨细胞和成骨SMC谱系的中间细胞相互作用。这种相互作用触发了转录因子 (TF) SP1 和 NFKB1 的激活，从而上调炎症反应和细胞衰老，并导致成骨细胞谱系的过早状态延迟和 SMC 谱系的成骨转变。然后，76。两种疾病之间，循环单核细胞中 49% 的常见单核细胞标志物上调，这些标志物与趋化性和炎症反应有关。最后，我们在循环单核细胞上鉴定了 7 个与钙化悖论相关的基因，这些基因在衰老细胞中上调，在 DNA 修复细胞中下调，表明衰老的单核细胞促进了这两种疾病的发生。结论 我们的工作基于 scRNA 和 mRNA 的综合数据，为理解 CD14+ 单核细胞在骨质疏松症和动脉粥样硬化相关细胞钙化悖论发展中的触发作用提供了一个视角。这项研究为我们阐明了钙化悖论的机制，并有助于制定预防和治疗策略。