Adipose tissue renin–angiotensin–aldosterone system (RAAS) and progression of insulin resistance

This review focuses on the expression of the key components of the renin–angiotensin–aldosterone axis in fat tissue. At the center of this report is the role of RAAS in normal and excessive fat mass enlargement, the leading etiology of insulin resistance. Understanding the expression and regulation of RAAS components in various fat depots allows insight not only into the processes by which these complex patterns are modified by the enlargement of adipose tissue, but also into their impact on local and systemic response to insulin.

► Key renin–angiotensin–aldosterone system (RAAS) components are expressed in fat tissue.
► RAAS is vital for fat mass expansion and Angiotensin II promotes fat cell enlargement.
► Large adipocytes thus formed become dysfunctional.
► Fat tissue RAAS induces insulin resistance through both local and systemic mechanisms.
► Fat tissue angiotensinogen and Ang II in obesity contribute to systemic RAAS effects.