Effect of TNF-α on NF-κB signaling in adipocytes.

<p>(A) Differentiated adipocytes were treated with 10 ng/ml TNF-α for 0, 5, 10, 15 and 30 minutes respectively and its effect on the levels of phospho-IκBα and phospho-NF-κB was detected by western blotting. α-tubulin served as the loading control. (B) Differentiated adipocytes were treated with different concentration (1, 10, 20 and 50 ng/ml) of TNF-α for 18 hours followed by analysis of the mRNA levels of IRS-1, GLUT4 and adiponectin by RT-PCR. Cells were treated with 2.5 and 5.0 µM of IKK-IV inhibitor followed by treatment with 20 ng/ml TNF-α. hβ2M was used as the internal control for normalizing mRNA levels. (C) Cells were treated with 1, 5, 10 and 20 ng/ml TNF-α for 24 hour and immunoblotted for IRS-1 and α-tubulin.