棕色脂肪组织产热功能的胞外调控机制OA

When long-term energy intake exceeds energy expenditure,obesity is induced.Energy expenditure driven by non-shivering thermogenesis is an important target for improving energy homeostasis and treating obesity.Brown adipose tissue(BAT)is the primary site of non-shivering thermogenesis,and its function is regulated by multiple systems through extracellular mechanisms.This review summarizes the extracellular regulatory mechanisms of BAT thermogenesis:the nervous system integrates cold and metabolic signals through the central-sympathetic neural axis,and hypothalamic neu-ral circuits sense lipid and hormonal states to dynamically adjust BAT thermogenic thresholds.In the immune system,macrophages participate in metabolic regulation through polarization dynamics,secretome remodeling and mitochondrial transfer,while mast cells and T cell subsets bidirectionally regulate the BAT microenvironment through cytokine networks.The digestive system influences BAT thermogenesis through gastrointestinal hormones(secretin,bile acids,cholecystokinin,glucagon-like peptide-1(GLP-1),etc.),liver-secreted proteins(pregnancy zone protein(PZP),fibro-blast growth factor 21(FGF21))and metabolites,as well as gut microbiota-derived metabolites(short-chain fatty acids,bile acids).In autocrine and paracrine mechanisms,BAT performs local regulation by secreting myostatin,irisin,mito-chondrial extracellular vesicle,vascular endothelial growth factor-α(VEGF-α),fibroblast growth factor 21(FGF21),and neuregulin 4.Additionally,BAT activation can delay atherosclerosis progression through mechanisms including lipid clearance,anti-inflammatory effects,and adipokine secretion.This review systematically outlines the extracellular regula-tory network of BAT thermogenesis,providing a theoretical foundation and potential intervention targets for the prevention and treatment of metabolic diseases.