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| Adipokine | Distribution | Function | Increased in obesity |
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| Leptin | Secreted predominantly by WAT, to a lesser degree, in hypothalamus, gastric epithelium, placenta, and gonads | Regulates energy intake, expenditure and feeding behavior. Also regulates storage of fat and insulin signaling | Increased in mouse models of obesity. Increased in human obesity and correlated with BMI and decreased with weight loss |
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| Resistin | In rodents, secreted by adipocytes. In humans, secreted predominantly by circulating macrophages and monocytes, to a lesser degree, by WAT | Implicated in glucose metabolism, in the regulation of neoglucogenesis and insulin resistance in rodents. More proinflammatory role in humans | Increased circulating concentrations in mouse models of obesity. Increased in human obesity and correlated with insulin resistance in diabetic patients |
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| TNF-α | Expressed by macrophages and adipocytes (visceral WAT > subcutaneous WAT) | Affects insulin and glucose metabolism. Provokes insulin resistance and stimulates lipolysis | Increased in mouse models of obesity. Increased in human obesity and correlated with BMI |
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| IL-6 | One-third of total circulating levels are expressed predominantly by adipocytes. Also expressed in macrophages, skeletal muscle, endothelial cells, and fibroblasts | Controversial role in the development of insulin resistance. Affects glucose metabolism | Increased circulating levels in human obese subjects and correlated with adiposity and reduced with weight loss. Increased in plasma of T2D patients |
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| IL-7 | Secreted by stromal and vascular endothelial cells | Homeostatic immune cytokine. Also regulates body weight, adipose tissue mass and function, and insulin signaling | Increased in morbidly obese subjects |
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| IL-8 | Secreted by adipocytes (visceral WAT > subcutaneous WAT) and macrophages | Neutrophil chemotaxis | Increased in obese subjects and related to fat mass and TNF-α levels |
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| IL-1 | Secreted mainly by adipocytes and macrophages | Role in macrophages chemotaxis and thermogenesis | Increased in obese mice. Increased in human obesity and predictive of T2D |
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| RBP4 | Secreted by adipocytes, macrophages, and hepatocytes | Affects insulin sensitivity, hepatic glucose output, and muscle insulin signaling | Increased circulating levels in obese subjects and correlated with BMI and insulin resistance |
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| MCP-1 | Secreted by adipose tissue | Affects insulin sensitivity and increases macrophage recruitment in adipose tissue and inflammation | Increased in mouse models of obesity. Increased in T2D subjects |
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| PAI-1 | Expressed by WAT | Potent inhibitor of fibrinolytic pathway | Increased in human obesity and T2D subjects |
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| CXCL5 | Secreted by macrophages within the stromal vascular fraction | Interferes with insulin signaling in muscle | Circulating levels are higher in obese insulin-resistant individuals than in obese insulin-sensitive and decreased after a 4-week period on low-calorie diet |
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| Visfatin | Expressed in liver, muscle, WAT, bone marrow, and lymphocytes | Role in insulin sensitivity, insulin secretion and inflammatory properties | Increased in obesity and correlates with visceral adiposity in humans |
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| Chemerin | In rodents and humans, expressed in placenta and WAT | Regulates adipocyte development and metabolic function | Increased circulating levels in obese and T2D patients and correlated with body fat, glucose, and lipid metabolism |
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| Vaspin | Secreted by WAT, hypothalamus, pancreatic islets, and skin | Improves insulin sensitivity | Increased in obesity and T2D patients |
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