IKKβ-dependent NF-κB pathway controls vascular inflammation and intimal hyperplasia

SPECIFIC AIMSThe aim of the study was to clarify the role of biphasic nuclear factor kappa B (NF-κB) signaling and IκB kinase β (IKKβ) in the process of vascular repair.PRINCIPAL FINDINGS1. Angioplastic injury elicits differential activation of NF-κB in media and intimaProgression of NF-κB activation was investigated in rat carotid artery subjected to angioplastic injury. Immunostaining for nuclear NF-κB p65 showed that the activated NF-κB signal was present in 55% of medial cells at day 3 postinjury. Later, the signal was located in intimal cells (84%) in conjunction with high levels of IKK activity at day 14. In contrast, a few p65 positive cells and weak IKK activity were detected in media, indicating that NF-κB activation was resolved at this stage in the media. These results suggest that angioplastic injury elicits two phases of NF-κB activation characterized by early activation in the media and a later activation in the intima.2. The early NF-κB activation underlies the early vascular inflammatory r...