Stem cell antigen-1 (
Sca1 or Ly6A/E) is a cell surface marker that is widely expressed in mesenchymal stem cells, including adipose-derived stem cells (ASCs). We hypothesized that the fat depot-specific gene signature of
Sca1(high) ASCs may play the major role in defining adipose tissue function and extracellular matrix (ECM) remodeling in a depot-specific manner. Herein we aimed to characterize the unique gene signature and ECM remodeling of
Sca1(high) ASCs isolated from subcutaneous (inguinal) and visceral (epididymal) adipose tissues.
Sca1(high) ASCs are found in the adventitia and perivascular areas of adipose tissues.
Sca1(high) ASCs purified with magnetic-activated cell sorting (MACS) demonstrate dendrite or round shape with the higher expression of
cytokines and
chemokines (e.g.,
Il6, Cxcl1) and the lower expression of a
glucose transporter (Glut1). Subcutaneous and visceral fat-derived
Sca1(high) ASCs particularly differ in the gene expressions of adhesion and ECM molecules. While the expression of the major membrane-type
collagenase (MMP14) is comparable between the groups, the expressions of secreted
collagenases (MMP8 and MMP13) are higher in visceral
Sca1(high) ASCs than in subcutaneous ASCs. Consistently, slow but focal
MMP-dependent collagenolysis was observed with subcutaneous adipose tissue-derived vascular stromal cells, whereas rapid and bulk collagenolysis was observed with visceral adipose tissue-derived cells in
MMP-dependent and -independent manners. These results suggest that the fat depot-specific gene signatures of ASCs may contribute to the distinct patterns of ECM remodeling and adipose function in different fat depots.