Table 1.

Summary of the effect of each adipokine on development of metabolic syndrome.

Adipokines	Role in Development of Metabolic Syndrome
Leptin	Increase [16] or decrease [17] in adipogenesis dependent on dosage Inhibition of insulin secretion [18], improvement of insulin sensitivity [19] Increase in fatty acid oxidation [20], decrease in circulating triglyceride level [21] Increase in blood pressure by sympathetic activation [22]
Adiponectin	Increase [23] or decrease [24] in adipocyte differentiation Improvement in insulin sensitivity [25] Decrease in foam cell formation [26], inhibition of intimal smooth muscle cell proliferation [27]
Visfatin	Decrease in insulin sensitivity [28] Increase in accumulation of cholesterol in macrophages [29], inducement of endothelial dysfunction [30], promotion of proliferation of vascular smooth muscle cells [31]
Fetuin-A	Increase in macrophage infiltration into adipose tissue [32] Decrease in insulin sensitivity [33] Increase in foam cell formation [34], prevention of arterial calcification [35]
PAI-1	Decrease in insulin sensitivity [36] Increase in liver steatosis, increase in serum cholesterol [37] Increase in atherogenesis with macrophage accumulation [38]
Resistin	Decrease in insulin sensitivity [39], increase in hepatic gluconeogenesis [40] Increase in lipolysis with increased serum free fatty acid and glycerol [41] Increase in foam cell formation [42], promotion of vascular smooth muscle cell apoptosis [43]
Omentin-1	Improvement in insulin sensitivity [44] Improvement in energy metabolism [45] Decrease in foam cell formation, size of atherosclerotic plaque, and infiltration of macrophages [46]
Lipocalin-2	Increase in insulin resistance [47] Increase in lipid accumulation [48] Increase in atherogenesis [49]
Asprosin	Increase in insulin secretion [50] Increase in serum triglyceride level [50,51]
Neuregulin 4	Improvement in insulin sensitivity [52] Decrease in liver steatosis [52]

Abbreviations: PAI-1, Plasminogen activator inhibitor-1.