Antagonistic crosstalk between NF-κB and SIRT1 in the regulation of inflammation and metabolic disorders

Recent studies have indicated that the regulation of innate immunity and energy metabolism are connected together through an antagonistic crosstalk between NF-kappa B and SIRT1 signaling pathways. NF-kappa B signaling has a major role in innate immunity defense while SIRT1 regulates the oxidative respiration and cellular survival. However, NF-kappa B signaling can stimulate glycolytic energy flux during acute inflammation, whereas SIRT1 activation inhibits NF-kappa B signaling and enhances oxidative metabolism and the resolution of inflammation. SIRT1 inhibits NF-kappa B signaling directly by deacetylating the p65 subunit of NF-kappa B complex. SIRT1 stimulates oxidative energy production via the activation of AMPK, PPAR alpha and PGC-1 alpha and simultaneously, these factors inhibit NF-kappa B signaling and suppress inflammation. On the other hand, NF-kappa B signaling down-regulates SIRT1 activity through the expression of miR-34a, IFN gamma, and reactive oxygen species. The inhibition of SIRT1 disrupts oxidative energy metabolism and stimulates the NF-kappa B-induced inflammatory responses present in many chronic metabolic and age-related diseases. We will examine the molecular mechanisms of the antagonistic signaling between NF-kappa B and SIRT1 and describe how this crosstalk controls inflammatory process and energy metabolism. In addition, we will discuss how disturbances in this signaling crosstalk induce the appearance of chronic inflammation in metabolic diseases. (C) 2013 Elsevier Inc. All rights reserved.