Table 1.

IR and inflammation.

Pro-inflammatory cytokines involved in IR
TNF-α	• Increases lipolysis • Increases circulatory FFA • Impairs insulin signaling
IL-1β	• Impairs insulin signaling • Reduces insulin sensitivity of β-cells
IL-6	• Reduces expression of GLUT-4 and IRS-1 • Inhibits the metabolism of nonoxidative glucose • Increases plasma triglycerides
Leptin (via leptin resistance)	• Impairs regulation of triglycerides • Promotes ectopic lipid accumulation
PAI-1	• Plays a major role in inflammation, obesity, and IR
MCP-1	• Induces adipocyte dedifferentiation

Abbreviations: FFA, free fatty acid; IR, insulin resistance.