Adipose tissue secretes a large number of pro- and anti-inflammatory adipokines. Adipokines modulate inflammation and insulin resistance. The expression of pro-inflammatory adipokines is enhanced with obesity, which induces insulin resistance. Obesity-induced insulin resistance may result, at least in part, from an imbalance in the expression of pro- and anti-inflammatory adipokines.
Over twenty adipokines have been identified. Some adipokines are secreted solely by adipocytes (fat cells); several are secreted by adipocytes and other body cells. Their role is widespread as they integrate with various body organs and tissues, including skeletal muscle, adrenal cortex, brain, and sympathetic nervous system. Adipokines function in:
- Energy balance
- Immune reactions
- Insulin sensitivity
- Angiogenesis
- Blood pressure maintenance
- Lipid metabolism
- Hemostasis
The adipokines that will be discussed on the following pages include:
- Tumor necrosis factor-alpha (TNF-α)
- Interleukin 6 (IL-6)
- Plasminogen activator inhibitor-1 (PAI-1)
- Adiponectin
- Angiotensinogen
- Leptin
- Resistin
