TNF and Insulin resistance: Overproduction of proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interferon-γ (IFN-γ) in obese animals may be responsible for chronic inflammation and insulin resistance, in part through the nuclear factor kappa-B (NF-κB) pathway (7, 23–28).