Fig. 8.

Effects of compounds on I-κBα and NF-κB p65 protein levels. Neurons were treated with the selected compounds and TNF-α 100 ng/ml for 24 hr and 30 min, respectively. A: Compounds SRI 22772 (10 µM), 22782 (1 µM), and 22820 (1 µM) did not cause a significant reduction of I-κBα in neurons (gray bars). TNF-α caused the expected, and significant, decrease in I-κB levels (black bar). B: Treatment with compounds SRI 22782 and 22820 resulted in a marked increase of NF-κB as indicated by cytoplasmic increase of p65 (gray bars). TNF caused a reduction of p65 levels because of translocation. C: Compounds SRI 22772, 22782, and 22820 caused NF-κB activation as indicated by the increase of NF-κB protein levels in the nucleus-enriched fraction (gray bars). As expected, TNF-α also increased p65 in the nuclear extracts (black bar). D: Summation of p65 protein levels from the cytoplasm and the nuclear fraction of neurons showed that the total NF-κB protein quantity is greatly increased by the compound treatment (gray bars) and to a lower extent by TNF-α (black bar). Error bars indicate the 5% confidence error limit.