Studies showed that monocyte chemotactic protein-1 (MCP-1) concentrations are increased in obesity. In our current study, we demonstrate that plasma MCP-1 level in leptin-deficient ob/ob mice is significantly higher than in lean mice. Furthermore, we determined that basal adipose tissue MCP-1 mRNA levels are significantly higher in ob/ob mice compared with lean mice. To determine the mechanisms underlying obesity-associated increases in plasma and adipose tissue MCP-1 levels, we determined adipose tissue cell type sources of MCP-1 production. Our data show that adipose tissue stem cells (CD34+), macrophages (F4/80+), and stromal vascular fraction (SVF) cells express significantly higher levels of MCP-1 compared with adipocytes under both basal and lipopolysaccharide (LPS)-stimulated conditions. Furthermore, basal and LPS-induced MCP-1 secretion levels were the same for both adipose F4/80 + and CD34+ cells, whereas adipose CD34+ cells have twofold higher cell numbers (30% of total SVF cells) compared with F4/80+ macrophages (15%). Our data also show that CD34+ cells from visceral adipose tissue depots secrete significantly higher levels of MCP-1 ex vivo when compared with CD34+ cells from subcutaneous adipose tissue depots. Taken together, our data suggest that adipose CD34 + stem cells may play an important role in obesity-associated increases in plasma MCP-1 levels.
|Original language||English (US)|
|Journal||American Journal of Physiology - Endocrinology and Metabolism|
|State||Published - Nov 2007|
- Adipose stem cell
- Adipose tissue
- Monocyte chemotactic protein-1
ASJC Scopus subject areas