IKKβ mediates homeostatic function in inflammation via competitively phosphorylating AMPK and IκBα.

Autor: Liu, Juan, Zhuang, Yuxin, Wu, Jianlin, Wu, Qiang, Liu, Meixian, Zhao, Yue, Liu, Zhongqiu, Wang, Caiyan, Lu, Linlin, Meng, Yingjiao, Lei, Kawai, Li, Xiaojuan, Wu, Qibiao, Leung, Elaine Lai-Han, Guo, Zhengyang, Liu, Liang, Li, Ting
Předmět:
Zdroj: Acta Pharmaceutica Sinica B; Feb2022, Vol. 12 Issue 2, p651-664, 14p
Abstrakt: Inhibitor of nuclear factor kappa-B kinase subunit beta (IKK β) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (I κ B α) and then activate nuclear factor kappa-B (NF- κ B). Inhibition of IKK β has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKK β is constitutively activated in healthy donors and healthy Ikkβ C46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKK β –I κ B α –NF- κ B signaling activation. These indicate that IKK β activation probably plays homeostatic role instead of causing inflammation. Compared to Ikkβ WT littermates, lipopolysaccharides (LPS) could induce high mortality rate in Ikkβ C46A mice which is correlated to breaking the homeostasis by intensively activating p-I κ B α –NF- κ B signaling and inhibiting phosphorylation of 5ʹ adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKK β kinase domain (KD) phosphorylates AMPK α 1 via interacting with residues Thr183, Ser184, and Thr388, while IKK β helix–loop–helix motifs is essential to phosphorylate I κ B α according to the previous reports. Kinase assay further demonstrated that IKK β simultaneously catalyzes phosphorylation of AMPK and I κ B α to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKK β could substantially rescue LPS-induced mortality in Ikkβ C46A mice by rebuilding the homeostasis. We conclude that IKK β activates AMPK to restrict inflammation and IKK β mediates homeostatic function in inflammation via competitively phosphorylating AMPK and I κ B α. The dual and opposite role of inhibitor of nuclear factor kappa-B kinase subunit beta (IKK β) restricts and induces inflammation by phosphorylating 5ʹ adenosine monophosphate-activated protein kinase (AMPK) and inhibitor of nuclear factor kappa-B (I κ B α). [Display omitted] [ABSTRACT FROM AUTHOR]
Databáze: Supplemental Index