The Vascular Endothelium of the Adipose Tissue Gives Rise to Both White and Brown Fat Cells

Abstract

Summary Adipose tissue expansion involves the enlargement of existing adipocytes, the formation of new cells from committed preadipocytes, and the coordinated development of the tissue vascular network. Here we find that murine endothelial cells (EC) of classic white and brown fat depots share ultrastructural characteristics with pericytes, which are pluripotent and can potentially give rise to preadipocytes. Lineage tracing experiments using the VE-cadherin promoter reveal localization of reporter genes in EC, and also in preadipocytes and adipocytes of white and brown fat depots. Furthermore, capillary sprouts from human adipose tissue, which have predominantly EC characteristics, are found to express Zfp423, a recently identified marker of preadipocyte determination. In response to PPARγ activation, endothelial characteristics of sprouting cells are progressively lost, and cells form structurally and biochemically defined adipocytes. Together these data support an endothelial origin of murine and human adipocytes, suggesting a model for how adipogenesis and angiogenesis are coordinated during adipose tissue expansion.

Adipogenesis: new insights into brown adipose tissue differentiation

“…Recently, work by Tran and colleagues reported that murine endothelial cells (ECs) of classic white and brown fat depots share ultrastructural characteristics with pericytes, a stem celllike population that can potentially differentiate into preadipocytes. Lineage tracing experiment using VE-cadherin promoter revealed localisation of reporter genes in not only pre-adipocytes and adipocytes of WAT and BAT depots but also in ECs (Tran et al 2012). Taken together, these results support an endothelial origin of murine and human adipocytes (Fig.…”

Identifying the Cellular Mechanisms Leading to Heterotopic Ossification

“…This is a highly significant finding given that HO is perhaps most commonly observed in skeletal muscle [90]. A derivational link between endothelial cells and adipocytes has also been identified, with capillary sprouts present in adipose tissue being found to express both endothelial (VE-Cadherin) and pre-adipocyte (Zfp423) markers [91]. Furthermore, the formation and expansion of adipose tissue is reliant on the presence of a rich capillary network.…”

Characterization of Human Adipose Tissue-Resident Hematopoietic Cell Populations Reveals a Novel Macrophage Subpopulation with CD34 Expression and Mesenchymal Multipotency

“…A previous study on ATMs in lean mice [11] reported that M2 ATMs reside between adipocytes and occasionally associated with blood vessels, which is supported by the present study. More recently, it was shown that some adipocytes originate from fetal vascular endothelium [36] and ASCs may be physiological progenitors for both adipocytes and vascular endothelial cells [37], which may also suggest a close relationship among CD206 + ATMs, adipocytes, and vascular cells.…”