The Heating Microenvironment: Intercellular Cross Talk Within Thermogenic Adipose Tissue

Abstract

Adipose tissue serves as the body's primary energy storage site; however, findings in recent decades have transformed our understanding of the multifaceted roles of this adaptable organ. The ability of adipose tissue to undergo energy expenditure through heat generation is termed adaptive thermogenesis, a process carried out by thermogenic adipocytes. Adipocytes are the primary parenchymal cell type in adipose tissue, yet these cells are sustained within a rich stromal vascular microenvironment comprised of adipose stem cells and progenitors, immune cells, neuronal cells, fibroblasts, and endothelial cells. Intricate cross talk between these diverse cell types is essential in regulating the activation of thermogenic fat, and the past decade has shed significant light on how this intercellular communication functions. This review will draw upon recent findings and current perspectives on the sophisticated repertoire of cellular and molecular features that comprise the adipose thermogenic milieu.

Figure 1

Intercellular cross talk in the thermogenic microenvironment. A diverse ensemble of stromal vascular cells interact with adipocytes and their precursors to orchestrate adipose thermogenesis. Created with BioRender.com. 5-HT, serotonin; ACh, acetylcholine; APCs, adipose precursor cells; BHB, β-hydroxybutyrate; BMP, bone morphogenetic proteins; Eos, eosinophil; ILC2, group 2 innate lymphoid cell; iNKT, invariant natural killer T cells; MΦ, macrophage; Met-Enk, methionine enkephalin peptide; NE, norepinephrine; SAM, sympathetic neuron-associated macrophage; TGFβ1, transforming growth factor β1; TNFα, tumor necrosis factor α; VEGFA, vascular endothelial growth factor A.