Dermal adipose tissue is a layer of adipocytes residing under the reticular dermis. Recent data have revealed a difference between the dermal adipose tissue and subcutaneous adipose tissue. Dermal adipocytes show dramatic changes in synchrony with hair cycling. Beyond hair cycling, many additional stimuli can modulate the volume of dermal adipose tissue. However, dermal adipose tissue remains poorly characterized. The fate of the mature dermal adipocytes and the origin of the re-appearing dermal adipocytes after they de-differentiate are still unclear. Here we isolated dermal adipocytes and characterized dermal fat as a fat pad with unique identity. Using pulsed lineage tracing of dermal mature adipocytes, as well as single cell sequencing, we reveal that mature dermal adipocytes can de-differentiate into fibroblast-like cells or even myofibroblast-like cells. Upon various stimuli, the de-differentiated fibroblasts proliferate and re-differentiated into adipocytes. Similar to other skin fibroblasts, the de-differentiated fibroblast-like cells showed two distinct clusters, and totally lose their mature adipocyte characteristics. In addition, manipulation of dermal adipose tissue highlights an important role of adipocytes for hair cycling and wound healing. This study advances our knowledge of dermal adipose tissue and implicates dermal adipocytes as essential components for normal skin morphology and function.
Z. Zhang: None. M. Shao: None. R.K. Gupta: None. P.E. Scherer: None.
