Two-Level Organization of Thermogenesis in Adipose Tissue: a Morphofunctional Hypothesis

Abstract

A new hypothesis based on structural and molecular heterogeneity of thermogenic adipocytes suggests that regulated thermogenesis in mammalian adipose tissues involves two structural-functional levels. The first level comprises typical brown fat and beige adipocytes of subcutaneous white fat depots. Being a part of the functional thermoregulatory system, this level of heat production is controlled by the appropriate hypothalamic centers. The second level is represented by visceral beige adipocytes with a relatively low total thermogenic capacity which provide a fine local adjustment of thermal optima for cell renewal processes. This level is regulated mainly by the local auto- and paracrine mechanisms.