Quantification of adipocyte numbers following adipose tissue remodeling

To analyze the capacity of white and brown adipose tissue remodeling, we developed two mouse lines to label, quantitatively trace, and ablate white, brown, and brite/beige adipocytes at different ambient temperatures. We show here that the brown adipocytes are recruited first and reach a peak after 1 week of cold stimulation followed by a decline during prolonged cold exposure. On the contrary, brite/beige cell numbers plateau after 3 weeks of cold exposure. At thermoneutrality, brown adipose tissue, in spite of being masked by a white-like morphology, retains its brown-like physiology, as Ucp1+ cells can be recovered immediately upon beta3-adrenergic stimulation. We further demonstrate that the recruitment of Ucp1+ cells in response to cold is driven by existing adipocytes. In contrast, the regeneration of the interscapular brown adipose tissue following ablation of Ucp1+ cells is driven by de novo differentiation. [Display omitted] •A method for quantitative analysis of adipose tissue plasticity•At thermoneutrality brown adipocytes (BA) with whitened morphology retain BA physiology•In cold, recruitment of Ucp1+ cells is driven from existing adipocytes•De novo adipocyte formation drives the regeneration of brown adipose tissue Moser et al. develop a mouse model to genetically quantify adipocytes. They use this model to quantify the adipose tissue remodeling processes in response to cold and thermoneutral housing temperatures.