New perspectives on obesity-induced adipose tissue fibrosis and related clinical manifestations

Abstract

Adipose tissue is a complex heterogeneous tissue composed of adipocytes along with several non-adipocyte populations, including blood, stromal, endothelial, and progenitor cells, as well as extracellular matrix (ECM) components. As obesity progresses, the adipose tissue expands dynamically through adipocyte hypertrophy and/or hyperplasia. This expansion requires continuous ECM remodeling to properly accommodate the size increase as well as functional changes. Upon reaching a hypertrophic threshold beyond the adipocyte buffering capacity, excess ECM components are deposited, causing fibrosis and ultimately resulting in unhealthy metabolic maladaptation. These complex ECM remodeling processes in adipose tissues are regulated by the local environment, several key mediators, and genetic factors that are closely linked to insulin sensitivity. It is crucial to understand how adipocytes interact with nonadipocyte populations and various mediators (i.e., immune cells, ECM components, and adipokines) during these processes. This mini-review provides an overview of the latest research into the biology of obesity-induced adipose tissue fibrosis and its related clinical manifestations, providing insight for further studies aimed at controlling metabolic syndrome and its comorbidities.

Keywords: Adipose tissue fibrosis; Brown/beige adipocytes; Extracellular matrix components; Insulin resistance; Obesity.