ABSTRACT
Inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (IκBα) and then activate nuclear factor kappa-B (NF-κB). Inhibition of IKKβ has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKKβ is constitutively activated in healthy donors and healthy Ikkβ C46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKKβ-IκBα-NF-κB signaling activation. These indicate that IKKβ 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-IκBα-NF-κB signaling and inhibiting phosphorylation of 5' adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKKβ kinase domain (KD) phosphorylates AMPKα1 via interacting with residues Thr183, Ser184, and Thr388, while IKKβ helix-loop-helix motifs is essential to phosphorylate IκBα according to the previous reports. Kinase assay further demonstrated that IKKβ simultaneously catalyzes phosphorylation of AMPK and IκBα to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKKβ could substantially rescue LPS-induced mortality in Ikkβ C46A mice by rebuilding the homeostasis. We conclude that IKKβ activates AMPK to restrict inflammation and IKKβ mediates homeostatic function in inflammation via competitively phosphorylating AMPK and IκBα.
ABSTRACT
Objective: To investigate the effect of macrophage-capping protein (CapG) on migration and proliferation of human gastric cancer cell line.Methods: Real-time PCR method was used to detect the expression of CapG gene in four gastric cancer cell lines, and AGS cells with low expression and transfection were selected as the research objects.Specific primers were designed for CapG and recombinant plasmids synthesized.A lentivirus packaging system which could express CapG was constructed, and a cell line stably expressing CapG was established by infecting human gastric cancer cell line AGS cells.The effect of overexpression of CapG gene on the growth and proliferation of AGS cells was analyzed by CCK8 assay.Cells cratch and Transwell assay were used to analyze the effect of overexpression of CapG gene on AGS cell migration.Results: After the overexpression of CapG, the growth rate of AGS cells was slightly lower than that of the control group, but there was no significant difference between the two groups (t=2.424, P=0.073).Scratch test showed that the average narrowing distance of the scratches in the CapG experimental group was significantly reduced compared with the control group, the average narrowing distance of the CapG experimental group and the control group was 336.99 μm and 45.54 μm, the difference was statistically significant (t=14.97, P=0.004).The average number of cell penetra-ting membrane in the CapG experimental group and the eGFP control group was 176 and 70, the number of the cells in the CapG experimental group was significantly higher than that of the control group (t=40.00, P<0.001).Conclusion: The overexpression of CapG gene has no significant effect on the growth and proliferation of AGS cells of gastric cancer cell line.Overexpression of CapG gene can promote the migration of AGS cells of gastric cancer cell lines.
ABSTRACT
Objective To explore the effects of using proton pump inhibitors (PPIs) on the outcomes of hip fracture.Methods Searches were conducted through Medline,Embase,Cochrane Library and Chinese Biomedical Literature Database to identify the studies of the association between PPIs exposure and hip fracture.Quality of studies was assessed using the Newcastle-Ottawa Quality Assessment Scale.Pooled odds ratios (ORs) and 95％ confidence interval (CIs) were calculated for the risk of hip fracture associated with current exposure of PPIs.And several subgroups were analyzed by dosing duration,dose,osteoporosis and corticosteroid usage to explore potential study heterogeneities.All statistical analyses were performed with STATA software.Results Among 11 publications included for final analysis,there were a total of 1 107 577 subjects with an average age of over 60 years.A positive relationship existed between PPIs exposure and hip fracture with an OR of 1.46 (95％ CI:1.26-1.70,P =0.000) as compared with nonPPI-users,especially those on concurrent corticosteroid and PPIs.A significantly increased risk of hip fracture was found in the group of a short-term duration for under 1 year (OR =1.18,95％ CI:1.01-1.38,P =0.041),medium-term for 1-3 years (OR =1.23,95％ CI:1.01-1.49,P =0.038) and longer duration for over 6 years (OR =1.38,95％ CI:1.27-1.50,P =0.000).Furthermore,concurrent use of PPIs was not associated with an increased risk of hip fracture in a definite dose-response manner.As compared with non-PPI-users,no significantly increased risk of hip fracture was found in PPI-users with osteoporosis (P ＞ 0.05).Publication bias was not present.Conclusions Use of PPIs may be somewhat associated with an increased risk of hip fracture.Considering potential adverse effects,clinicians should prescribe cautiously PPIs for high-risk patients,especially elders.