MAGP1, the extracellular matrix, and metabolism.

Adipose tissue and the extracellular matrix were once considered passive players in regulating physiological processes. Now, both entities are acknowledged for their capacity to engage signal transduction pathways, and for their involvement in maintaining normal tissue homeostasis. We recently published a series of studies that identified a novel mechanism whereby an extracellular matrix molecule, MAGP1 (microfibril associated glycoprotein 1), can regulate energy metabolism in adipose tissue. MAGP1 is a component of extracellular microfibrils and plays a supportive role in maintaining thermoregulation by indirectly regulating expression of the thermogenic uncoupling proteins (UCPs). The focus of this commentary is to draw attention to the role of the extracellular matrix in regulating the bioavailability of signaling molecules, like transforming growth factor β (TGFβ), and exemplify that a better understanding of the extracellular matrix's biological properties could unveil a new source of therapeutic targets for metabolic diseases.