Key Roles of Brown, Subcutaneous, and Visceral Adipose Tissues in Obesity and Insulin Resistance

Adipose tissue is a dynamic and heterogeneous organ with distinct depots that play divergent roles in metabolic regulation. This review highlights the functional differences between brown, subcutaneous, and visceral adipose tissue, and their contributions to obesity-related insulin resistance. We explore how chronic low-grade inflammation, mitochondrial dysfunction, and fibrosis evolve within specific fat depots and how these changes disrupt systemic energy homeostasis. Visceral white adipose tissue (vWAT) emerges as a critical site of inflammation and metabolic inflexibility, while subcutaneous white adipose tissue (sWAT) may retain protective features in early obesity. The endocrine roles of adipokines and batokines are also discussed, emphasizing depot-specific signaling and systemic effects. Furthermore, we examine emerging therapeutic strategies aimed at modulating immune responses, enhancing mitochondrial function, and reprogramming adipose progenitor cells (APCs) to restore healthy tissue remodeling. A deeper understanding of adipose-depot-specific biology and progenitor cell dynamics offers promising avenues for personalized interventions in metabolic diseases.