scRNA-seq of stromal vascular cells from 48 week (aged) mouse subcutaneous adipose tissue compared to control 10 week (young) mouse SVF

Adipose tissue mass and adiposity change throughout the lifespan. During aging, while visceral adipose tissue (VAT) tends to increase, peripheral subcutaneous adipose tissue (SAT) decreases significantly. Unlike VAT, which is linked to metabolic diseases, SAT has beneficial effects. However, the molecular details behind aging-associated loss of SAT remain unclear. Here we compare scRNA-seq of total SVF of SAT from young and aging mice to identify a novel Aging-dependent Regulatory Cell (ARC) that emerges in SAT of aged mice. Inguinal white adipose tissue (iWAT) was used as a representative SAT; iWAT pads of 2 mice from each age group were subjected to collagenase digestion and treated with a hypotonic buffer to remove red blood cells before subjection to scRNA-seq by 10X Genomics Chromium Single Cell Kit. The findings showed that ARCs express adipogenic markers but lack adipogenic capacity and inhibit differentiation of neighboring adipose precursors.脂肪组织总量与体脂水平随生命周期发生动态变化。在衰老进程中，内脏脂肪组织（visceral adipose tissue, VAT）通常呈增加趋势，而外周皮下脂肪组织（subcutaneous adipose tissue, SAT）则会显著减少。与代谢疾病相关的VAT不同，SAT发挥着有益的生理作用。然而，衰老相关的SAT流失背后的分子机制仍未阐明。本研究对年轻与衰老小鼠SAT的总基质血管成分（stromal vascular fraction, SVF）进行单细胞RNA测序（single-cell RNA sequencing, scRNA-seq）比对分析，成功鉴定出一种在衰老小鼠SAT中特异性出现的新型衰老依赖性调节细胞（Aging-dependent Regulatory Cell, ARC）。本研究以腹股沟白色脂肪组织（inguinal white adipose tissue, iWAT）作为SAT的代表性样本；每个年龄组取2只小鼠的腹股沟白色脂肪组织垫，经胶原酶消化后使用低渗缓冲液去除红细胞，随后通过10X Genomics Chromium单细胞试剂盒完成单细胞RNA测序。研究结果显示，ARC表达成脂标志物，但不具备成脂分化能力，且可抑制邻近脂肪前体细胞的分化。