Regulation of NF-κB activation through a novel PI-3K-independent and PKA/Akt-dependent pathway in human umbilical vein endothelial cells.
Regulation of NF-κB activation through a novel PI-3K-independent and PKA/Akt-dependent pathway in human umbilical vein endothelial cells.
复制标题
DOI：
10.1371/journal.pone.0046528
复制
发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Ghosh B
中科院分区：
文献类型：
--
作者：
Balwani S;Chaudhuri R;Nandi D;Jaisankar P;Agrawal A;Ghosh B
转录因子NF-κB调节许多炎症性疾病，并且参与NF-κ B活化信号通路的蛋白质是重要的治疗靶点。在人脐静脉内皮细胞（HUVECs）中，TNF-α诱导的IκBα降解和p65/RelA磷酸化调节NF-κB活化。这些由IKK（IκB激酶）即IKKα、β和γ介导，IKKα、β和γ从上游激酶如Akt接收激活信号。已知Akt受PI-3 K（磷酸肌醇-3-激酶）正调控，并在各种细胞类型中通过蛋白激酶A（PKA）差异调控。然而，PKA/Akt相互作用在调节NF-κB在HUVECs中的作用尚未被研究。在此，我们使用一种新的化合物2-甲基-吡喃-4-酮-3-O-β-D-2′，3 ′，4 ′，6 ′-四-O-乙酰基吡喃葡萄糖苷（MPTAG）检测了PKA/Akt在HUVECs中的相互作用。我们观察到MPTAG不直接抑制IKK-β，但通过阻断其与Akt的结合来阻止TNF-α诱导的IKK-β活化，从而抑制NF-κB活化。有趣的是，我们的结果还显示，MPTAG对Akt和NF-κB活化的抑制作用不受wortmannin的影响，并且在这些细胞中被H-89处理完全消除。因此，MPTAG介导的TNF-α诱导的Akt活化的抑制不依赖于PI-3 K，而依赖于PKA。最重要的是，MPTAG恢复了PKA的活性，并抑制TNF-α诱导的Akt在Thr 308和Ser 473残基的磷酸化。因此，我们首次证明PKA/Akt交叉作用参与了HUVECs中NF-κB的激活。此外，MPTAG可用作开发NF-κB活化起关键作用的疾病的有效治疗分子的先导分子。
The transcription factor NF-κB regulates numerous inflammatory diseases, and proteins involved in the NF-κB-activating signaling pathway are important therapeutic targets. In human umbilical vein endothelial cells (HUVECs), TNF-α-induced IκBα degradation and p65/RelA phosphorylation regulate NF-κB activation. These are mediated by IKKs (IκB kinases) viz. IKKα, β and γ which receive activating signals from upstream kinases such as Akt. Akt is known to be positively regulated by PI-3K (phosphoinositide-3-kinase) and differentially regulated via Protein kinase A (PKA) in various cell types. However, the involvement of PKA/Akt cross talk in regulating NF-κB in HUVECs has not been explored yet. Here, we examined the involvement of PKA/Akt cross-talk in HUVECs using a novel compound, 2-methyl-pyran-4-one-3-O-β-D-2′,3′,4′,6′-tetra-O-acetyl glucopyranoside (MPTAG). We observed that MPTAG does not directly inhibit IKK-β but prevents TNF-α-induced activation of IKK-β by blocking its association with Akt and thereby inhibits NF-κB activation. Interestingly, our results also revealed that inhibitory effect of MPTAG on Akt and NF-κB activation was unaffected by wortmannin, and was completely abolished by H-89 treatment in these cells. Thus, MPTAG-mediated inhibition of TNF-α-induced Akt activation was independent of PI-3K and dependent on PKA. Most importantly, MPTAG restores the otherwise repressed activity of PKA and inhibits the TNF-α-induced Akt phosphorylation at both Thr308 and Ser473 residues. Thus, we demonstrate for the first time the involvement of PKA/Akt cross talk in NF-κB activation in HUVECs. Also, MPTAG could be useful as a lead molecule for developing potent therapeutic molecules for diseases where NF-κB activation plays a key role.
登录
查看更多内容
DOI：
10.4061/2011/216298
发表时间：
2011
期刊：
Parkinson's disease
影响因子：
--
作者：
Flood PM;Qian L;Peterson LJ;Zhang F;Shi JS;Gao HM;Hong JS
通讯作者：
Hong JS
影响因子：
56.9
作者：
KOPP, E;GHOSH, S
通讯作者：
GHOSH, S
影响因子：
4.8
作者：
Gratton, JP;Morales-Ruiz, M;Sessa, WC
通讯作者：
Sessa, WC
影响因子：
4.8
作者：
Blonska, M;Shambharkar, PB;Lin, X
通讯作者：
Lin, X
DOI：
10.1006/bbrc.2000.2626
发表时间：
2000-05-10
影响因子：
3.1
作者：
Burow, ME;Weldon, CB;McLachlan, JA
通讯作者：
McLachlan, JA