Regulation of I kappa B alpha Function and NF-kappa B Signaling: AEBP1 Is a Novel Proinflammatory Mediator in Macrophages

NF-kappa B comprises a family of transcription factors that are critically involved in various inflammatory processes. In this paper, the role of NF-kappa B in inflammation and atherosclerosis and the regulation of the NF-kappa B signaling pathway are summarized. The structure, function, and regulation of the NF-kappa B inhibitors, I kappa B alpha and I kappa B beta, are reviewed. The regulation of NF-kappa B activity by glucocorticoid receptor (GR) signaling and I kappa B alpha sumoylation is also discussed. This paper focuses on the recently reported regulatory function that adipocyte enhancer-binding protein 1 (AEBP1) exerts on NF-kappa B transcriptional activity in macrophages, in which AEBP1 manifests itself as a potent modulator of NF-kappa B via physical interaction with I kappa B alpha and a critical mediator of inflammation. Finally, we summarize the regulatory roles that recently identified I kappa B alpha-interacting proteins play in NF-kappa B signaling. Based on its proinflammatory roles in macrophages, AEBP1 is anticipated to serve as a therapeutic target towards the treatment of various inflammatory conditions and disorders.