Marrow Adipose Tissue: Its Origin, Function, and Regulation in Bone Remodeling and Regeneration.

Qiwen Li,Yunshu Wu,Ning Kang

doi:10.1155/2018/7098456

Abstract

Marrow adipose tissue (MAT) is a unique fat depot in the bone marrow and exhibits close relationship with hematopoiesis and bone homeostasis. MAT is distinct from peripheral adipose tissue in respect of its heterogeneous origin, site-specific distribution, and complex and perplexing function. Though MAT is indicated to function in hematopoiesis, skeletal remodeling, and energy metabolism, its explicit characterization still requires further research. In this review, we highlight recent advancement made in MAT regarding the origin and distribution of MAT, the local interaction with bone homeostasis and hematopoietic niche, the systemic endocrine regulation of metabolism, and MAT-based strategies to enhance bone formation.

Highlights

Bone is a dynamic organ undergoing constant remodeling, where bone formation and resorption are tightly controlled by local signals and systemic cues [1, 2]
Marrow adipose tissue (MAT) was merely considered a space filler of the BM with unknown origin and function. This view persisted until 1992 when Beresford et al proposed the opinion that osteoblasts and adipocytes share the same progenitors, known as bone marrow mesenchymal stromal cells (BMSCs) [5]
Bone marrow adipocytes were induced with rosiglitazone, and the results showed that adipocytes were uniformly dTomato+, suggesting that the newly formed bone marrow adipocytes were not related to brown adipocyte lineage

Summary

Introduction

Bone is a dynamic organ undergoing constant remodeling, where bone formation and resorption are tightly controlled by local signals and systemic cues [1, 2]. MAT was merely considered a space filler of the BM with unknown origin and function. This view persisted until 1992 when Beresford et al proposed the opinion that osteoblasts and adipocytes share the same progenitors, known as bone marrow mesenchymal stromal cells (BMSCs) [5]. As well as the employment of novel experiment techniques such as lineage tracing, it is acknowledged that MAT originates from skeletal lineages, functioning crucially in bone and bone marrow homeostasis, and is associated with systemic energy metabolism [3, 4]. Regulating signals of MAT and bone remodeling, as well as strategies targeting MAT to promote bone regeneration, will be discussed

Development of MAT

MAT and Bone Marrow Homeostasis

Targeting MAT to Promote Skeletal Regeneration

Findings

Outlook