Adipokinas

Adipokinas, known in English as adipokines, are a broad class of bioactive proteins and peptides secreted predominantly by adipose tissue. They act as hormones and signaling molecules that regulate energy homeostasis, glucose and lipid metabolism, appetite, inflammation, and insulin sensitivity. The adipose tissue functions as an endocrine organ, releasing adipokines into the circulation and communicating with liver, muscle, brain, vasculature, and immune cells through autocrine, paracrine, and endocrine pathways.

Among the best characterized adipokinas are leptin, adiponectin, resistin, visfatin (Nampt), chemerin, omentin, and others such as apelin and vaspin. Leptin signals energy sufficiency to the hypothalamus and helps regulate appetite, though obesity is often associated with leptin resistance. Adiponectin enhances insulin sensitivity and has anti-inflammatory effects; unlike many adipokines, its levels decline with increasing adiposity. Resistin and visfatin have been linked to insulin resistance and inflammatory pathways, though findings in humans are variable. Chemerin, omentin, and other adipokinas participate in immune cell recruitment, vascular function, and metabolic regulation.

Dysregulation of adipokinas is a hallmark of obesity and metabolic syndrome. Expanded adipose tissue frequently exhibits increased production of pro-inflammatory cytokines (for example TNF-α, IL-6) and reduced adiponectin, contributing to chronic low-grade inflammation, insulin resistance, and cardiovascular risk. Adipokinas are studied as biomarkers of metabolic disease and as potential therapeutic targets, with lifestyle factors such as weight loss and physical activity shown to favor a healthier adipokine profile.