Visfatin Induces Inflammation and Insulin Resistance via the NF-κB and STAT3 Signaling Pathways in Hepatocytes

Figure 4

The visfatin-induced increases in proinflammatory cytokine levels are mediated by STAT3 and NF-κB. (a) HepG2 cells were preincubated with AG490 (5 μM) and BAY11-7082 (5 μM) for 1 hour before exposure to visfatin (200 ng/mL) for 6 hours. The levels of the inflammatory cytokines IL-6, TNF-α, and IL-1β were measured by real-time PCR. (b) HepG2 cells were preincubated with AG490 (5 μM) and BAY11-7082 (5 μM) for 1 hour before exposure to visfatin (200 ng/mL) for 24 hours. The concentrations of IL-6, TNF-α, and IL-1β in the culture supernatants were measured by ELISA. (c and d) HepG2 cells were preincubated with AG490 (5 μM) and BAY11-7082 (5 μM) for 1 hour before exposure to visfatin (200 ng/mL) for 24 hours. STAT and NF-κB signaling was measured using antibodies against phospho-STAT3, phospho-NF-κB, and actin. The maximum phosphoprotein intensities in visfatin-treated samples were set to 100%, and the relative intensities of test samples were then calculated. The data are of those of three independent experiments. , , and compared to the control.

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