Fractalkine: A Cellular Link Between Adipose Tissue Inflammation and Vascular Pathologies
- Joint Program on Diabetes, Endocrinology, and Metabolism, Louisiana State University Health Sciences Center School of Medicine, New Orleans, Louisiana, and the Pennington Biomedical Research Center, Baton Rouge, Louisiana
- Corresponding author: William T. Cefalu,
It is hard to imagine, given the wealth of new data reported over the recent past, that adipose tissue at one time was primarily considered as a passive reservoir for energy deposition and storage. However, research beginning in the early 1990s on the role of tumor necrosis factor (TNF)-α ushered in a new era of investigation, and since that time, there has been an incredibly rapid and substantive increase in our understanding of underlying physiologic systems and molecular pathways linking obesity, inflammation, and insulin action (1,2). Specifically, our understanding of the link between obesity and carbohydrate metabolism has been significantly enhanced with the elucidation of key regulators of energy balance and cellular insulin signaling that are complex and highly integrated (3–6). We now readily accept adipose tissue as a key endocrine organ regulating processes throughout the body with its significant number of adipocyte secretions. What now appears to be emerging is the elucidation of cellular pathways that are operative at not only the level of the adipocyte, but appear in common with those reported in vascular tissue. Such a cellular mechanism that may link pathophysiologic processes between adipose and vascular tissue is the fractalkine chemokine system as reported in this issue of Diabetes by Shah et al. (7). Specifically, Shah et al. provide interesting data that suggest that fractalkine (CX3CL1), a chemokine whose source is the endothelium and is postulated to play a role in atherogenesis, is also expressed in obese adipose tissue and plays a role in monocyte adhesion processes. These data provide an intriguing molecular link between obesity-related metabolic dysfunction and cardiovascular disease (CVD) in humans.
Fractalkine, a chemokine that signals through a single known receptor (CX3CR1), has received considerable interest in …