CTRP-3: Blocking a Toll Booth to Obesity-Related Inflammation

Extract

Over the last decade, our understanding of adipose tissue has changed significantly, and where it was once thought of as a simple energy storage site, it is now considered an important and immunologically active endocrine organ (1–3). Adipose tissue is composed of both metabolically and immunologically active cells that include adipocytes, preadipocytes, macrophages, endothelial cells, fibroblasts, and leukocytes; and in the omentum, this also includes omental mesothelial cells (1, 4). A network of blood vessels surrounds these cells and allows them to communicate with systemic sites. This coupling of metabolism and immunity in adipose tissue is a clever biological organization that allows efficient cross talk between these two pathways. This allows the host to make rapid metabolic changes in response to activation of host defense mechanisms against pathogens. This cross talk is achieved by more than 100 proinflammatory, antiinflammatory, and immunomodulating proteins and peptides (3). These include adipokines, such as leptin, adiponectin, visfatin, omentin, and resistin, as well as inflammatory cytokines TNFα, monocyte chemoattractant protein-1 (MCP-1), and plasminogen activator inhibitor-1.