Naomi Berrie Diabetes Center, Columbia University, New York, NY, United States.
Department of Pharmacology, Columbia University, New York, NY, United States.
Front Endocrinol (Lausanne). 2022 Mar 11;13:853765. doi: 10.3389/fendo.2022.853765. eCollection 2022.
Once considered an inert filler of the bone cavity, bone marrow adipose tissue (BMAT) is now regarded as a metabolically active organ that plays versatile roles in endocrine function, hematopoiesis, bone homeostasis and metabolism, and, potentially, energy conservation. While the regulation of BMAT is inadequately understood, it is recognized as a unique and dynamic fat depot that is distinct from peripheral fat. As we age, bone marrow adipocytes (BMAds) accumulate throughout the bone marrow (BM) milieu to influence the microenvironment. This process is conceivably signaled by the secretion of adipocyte-derived factors including pro-inflammatory cytokines and adipokines. Adipokines participate in the development of a chronic state of low-grade systemic inflammation (inflammaging), which trigger changes in the immune system that are characterized by declining fidelity and efficiency and cause an imbalance between pro-inflammatory and anti-inflammatory networks. In this review, we discuss the local effects of BMAT on bone homeostasis and the hematopoietic niche, age-related inflammatory changes associated with BMAT accrual, and the downstream effect on endocrine function, energy expenditure, and metabolism. Furthermore, we address therapeutic strategies to prevent BMAT accumulation and associated dysfunction during aging. In sum, BMAT is emerging as a critical player in aging and its explicit characterization still requires further research.
骨髓脂肪组织（BMAT）曾被认为是骨髓腔中的惰性填充物质，现在被认为是一种具有代谢活性的器官，在内分泌功能、造血、骨稳态和代谢以及潜在的能量保存中发挥着多样的作用。虽然对 BMAT 的调节机制了解不足，但它被认为是一种独特而活跃的脂肪库，与外周脂肪不同。随着年龄的增长，骨髓脂肪细胞（BMAds）在骨髓（BM）环境中积累，影响微环境。这个过程可能是由脂肪细胞衍生的因子（包括促炎细胞因子和脂肪因子）的分泌所信号传递的。脂肪因子参与慢性低度全身炎症（炎症老化）的发展，触发免疫系统的变化，其特征是保真度和效率下降，并导致促炎和抗炎网络之间的失衡。在这篇综述中，我们讨论了 BMAT 对骨稳态和造血龛的局部影响、与 BMAT 积累相关的与年龄相关的炎症变化，以及对内分泌功能、能量消耗和代谢的下游影响。此外，我们还探讨了预防 BMAT 积累和相关功能障碍的治疗策略。总之，BMAT 正在成为衰老过程中的一个关键因素，其明确特征仍需要进一步研究。
