Effect Of NfκB Dependent JNK Pathway On Dysfunction Of HUVECs Induced By Intermittent High Glucose And The Difference Of Gene Expression Profile Before And After Knockdown Of NF-κB/p65

Background Our previous study found that blocking nuclear factor (NF)-κB signaling could protect human umbilical vein endothelial cells (HUVECs) from apoptosis and proliferation inhibition due to either continuous or intermittent high glucose (HG). Intermittent HG makes glucose toxicity more obviously. In this study, we further investigate the effect of NF-κB pathway on HUVECs induced by intermittent HG (a daily alternating 5.5 or 30.5 mmol/l glucose).Methods A recombinant adenovirus containing a RNAi cassette targeting the NF-κB/p65 gene was used, and its silencing effect on p65 gene was proved in our study before and now. In addition, we study the JNK activity by Western blot analysis after knockdown of NF-κB/p65. Further more, DNA microarrays were used to investigate the difference of gene expression profile before and after knockdown of NF-κB/p65 in cultured human umbilical vein endothelial cells (HUVEC) exposed to intermittent HG for 7 days.Results The results showed that the activation of NF-κB following exposure to intermittent high glucose leads to activation of pro-apoptotic JNK signaling, and knockdown of NF-κB/p65 could reversed the increased JNK activity. As to DNA microarrays, we found 64 known genes up-regulated and 12 known genes down-regulated. Conclusion In this study, we propose that the activated NF-κB-dependent JNK signaling pathway is involved in the apoptosis and proliferation inhibition induced by high glucose. Moreover, we also suggested that up-regulation of integrin and down-regulation of TBP531 after knockdown of NF-κB/p65 could contribute to cell survival and provide protection on the endothelial cells from apoptosis.