Summary AMPK activation is beneficial for cellular homeostasis and senescence prevention. However, the molecular events involved in AMPK activation are not well defined. In this study, we addressed the mechanism underlying the protective effect of AMPK on oxidative stress‐induced senescence. The results showed that AMPK was inactivated in senescent cells. However, pharmacological activation of AMPK by metformin and berberine significantly prevented the development of senescence and, accordingly, inhibition of AMPK by Compound C was accelerated. Importantly, AMPK activation prevented hydrogen peroxide‐induced impairment of the autophagic flux in senescent cells, evidenced by the decreased p62 degradation, GFP‐RFP‐LC3 cancellation, and activity of lysosomal hydrolases. We also found that AMPK activation restored the NAD + levels in the senescent cells via a mechanism involving mostly the salvage pathway for NAD + synthesis. In addition, the mechanistic relationship of autophagic flux and NAD + synthesis and the involvement of mTOR and Sirt1 activities were assessed. In summary, our results suggest that AMPK prevents oxidative stress‐induced senescence by improving autophagic flux and NAD + homeostasis. This study provides a new insight for exploring the mechanisms of aging, autophagy and NAD + homeostasis, and it is also valuable in the development of innovative strategies to combat aging.

Whether dendritic cell (DC) derived exosomes play a role in the progression of endothelial inflammation and atherosclerosis remains unclear. Using a transwell system and exosome release inhibitor GW4869, we demonstrated that mature DCs contributed to endothelial inflammation and exosomes were involved in the process. To further confirm this finding, we isolated exosomes from bone marrow dendritic cell (BMDC) culture medium (named DC‐exos) and stimulated human umbilical vein endothelial cell (HUVEC) with these DC‐exos. We observed that mature DC‐exos increased HUVEC inflammation through NF‐κB pathway in a manner similar to that of lipopolysaccharide. After a protein array analysis of exosomes, we identified and confirmed tumour necrosis factor (TNF)‐α on exosome membrane being the trigger of NF‐κB pathway in HUVECs. We then performed an in vivo study and found that the aorta endothelial of mice could uptake intravenously injected exosomes and was activated by these exosomes. After a period of 12 weeks of mature DC‐exos injection into ApoE−/− mice, the atherosclerotic lesions significantly increased. Our study demonstrates that mature DCs derived exosomes increase endothelial inflammation and atherosclerosis via membrane TNF‐α mediated NF‐κB pathway. This finding extends our knowledge on how DCs affect inflammation and provides a potential method to prevent endothelial inflammation and atherosclerosis.

Summary S100A9 belongs to the S100 family of calcium-binding proteins and plays a key role in many inflammatory conditions. Recent studies have found that S100A9 was elevated significantly in the bronchoalveolar lavage fluid of idiopathic pulmonary fibrosis patients, and might be a biomarker for fibrotic interstitial lung diseases. However, the exact function of S100A9 in pulmonary fibrosis needs further studies. We performed this study to investigate the effect of S100A9 on human embryo lung fibroblast (HLF) proliferation and production of cytokines and collagen, providing new insights into the possible mechanism. S100A9 promoted proliferation of fibroblasts and up-regulated expression of both proinflammatory cytokines interleukin (IL)-6, IL-8, IL-1β and collagen type III. S100A9 also induced HLF cells to produce α-smooth muscle actin (α-SMA) and receptor for advanced glycation end-product (RAGE). In addition, S100A9 caused a significant increase in extracellular-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) phosphorylation, while the status of p38 and c-Jun N-terminal kinase (JNK) phosphorylation remained unchanged. Treatment of cells with S100A9 also enhanced nuclear factor kappa B (NF-κB) activation. RAGE blocking antibody pretreatment inhibited the S100A9-induced cell proliferation, cytokine production and pathway phosphorylation. S100A9-mediated cell activation was suppressed significantly by ERK1/2 MAPK inhibitor and NF-κB inhibitor. In conclusion, S100A9 promoted HLF cell growth and induced cells to secret proinflammatory cytokines and collagen through RAGE signalling and activation of ERK1/2 MAPK and NF-κB pathways.

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Hepatitis B virus (HBV) prevalence has declined remarkably in children due to nationwide universal vaccination program for HBV in China. However, the persistence of immune response against HBV infection and the optimal time point when a booster vaccination should be performed remain to be elucidated. To assess the persistence and level of antibody against hepatitis B surface antigen (anti-HBs) in a representative population of age 15 and younger who received routine hepatitis B vaccination in Mianyang City, China. A cross-sectional study was conducted in 2011. One thousand five hundred twenty-six children of age 15 and younger who received three doses of 5 μg hepatitis B vaccine series during infancy but did not receive a booster vaccination later were enrolled. Of the 1,526 children, the mean age was 8.2 ± 4.1 and 739 children were male. The median anti-HBs level was 23.0 mIU/mL, and the total percentage of anti-HBs levels ≥10 mIU/mL was 60.9%. With an increase of age, median anti-HBs level, percentage of anti-HBs levels ≥10 mIU/mL, and percentage of anti-HBs levels ≥100 mIU/mL declined remarkably in the early period and reached the lowest level at the age of 3 and then remained relatively stable. The median anti-HBs level, the percentage of anti-HBs levels ≥10 mIU/mL, and the percentage of anti-HBs levels ≥100 mIU/mL in 1- and 2-year-old children were much higher than that in children aged 3-15 (p < 0.05, respectively). Immunity against HBV infection gradually decreased in early ages of children of 15 and younger who received three doses of 5 μg hepatitis B vaccine series during infancy in China. Three dosages of 10 μg hepatitis B vaccine for infants and repeated vaccination or additional booster vaccination for some children at or before age 3 should be provided to get much more powerful immunity to HBV.

Background and Aims: Ravidasvir (RDV) is a new generation pangenotypic hepatitis C virus (HCV) NS5A inhibitor, with high barrier to baseline resistance-associated species. This is the first phase 2/3 study conducted in Mainland China confirming the efficacy and safety of RDV + ritonavir-boosted danoprevir + ribavirin for 12 weeks in treatment-naïve noncirrhotic patients with genotype 1 infection in a large population.Methods: In this multicenter, randomized, double-blinded, placebo-controlled phase 2/3 trial (NCT03362814), we enrolled 424 treatment-naïve, noncirrhotic adult HCV genotype 1 patients. All patients were randomized at 3:1 ratio to receive a combination of RDV 200mg once daily plus ritonavir-boosted danoprevir 100mg/100mg twice daily and oral ribavirin 1000/1200mg/day (body weight <75/≥75 kg) (n = 318) or placebo (n = 106) for 12 weeks. The primary end-point was the rate of sustained virologic response 12 weeks after the end of treatment, and the safety was evaluated and compared between treatment and placebo groups.Results: The overall rate of sustained virological response at 12 weeks after treatment is 99% (306/309, 95%, CI: 97%–100%) under per protocol set analysis. All patients harboring baseline NS5A resistance-associated species in the treatment group (76/76, per protocol set) achieved sustained virological response at 12 weeks after treatment. No treatment-related serious adverse events were reported. Laboratory abnormalities showed mild or moderate severity (grade 1 and grade 2) in liver function tests.Conclusions: In treatment-naïve, noncirrhotic HCV Chinese patients infected with HCV genotype 1, all-oral regimen of RDV + ritonavir-boosted danoprevir + ribavirin for 12 weeks was highly efficacious, safe, and well tolerated.

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Background: Patients with acute-on-chronic liver failure (ACLF) might be at risk for citrate accumulation during plasma adsorption plus plasma exchange (PE) therapy with regional citrate anticoagulation (RCA). Objectives: To assess the safety and efficacy of RCA during double plasma molecular adsorption system (DPMAS) plus PE therapy for patients with ACLF. Method: A prospective nonrandomized controlled pilot study was conducted at West China Hospital of Sichuan University. Patients with ACLF were enrolled to heparin anticoagulation (HA) group and RCA group. Serial blood samples were taken. Patients were followed up for 3 months. Results: Twenty-four patients with 94 sessions of HA and 28 patients with 106 sessions of RCA were enrolled. RCA method did not affect the therapeutic efficacy, the function of extracorporeal circulation, and the prognosis of these patients. The occurrences of citrate accumulation in RCA group were 0.0, 67.0, 100.0, 34.0, and 0.0% before DPMAS therapy, at the end of DPMAS therapy, immediately after PE therapy, 2 h after PE therapy, and the next morning, while that in HA group were 0.0, 0.0, 100.0, 7.4, and 0.0%, respectively. The occurrences of citrate accumulation at the end of DPMAS therapy and at 2 h after PE therapy in RCA group were much higher than that in HA group (67.0 vs. 0.0%, p = 0.000; 34.0 vs. 7.4%, p = 0.000, respectively). Although the trend of citrate accumulation in RCA group was much more obvious than that in HA group during and after DPMAS plus PE therapy (p = 0.000), the values on the next morning were similar between the 2 groups (p > 0.05). The main alteration of acid–base status was metabolic alkalosis with no difference between the 2 groups. Conclusions: RCA might be safe and effective in patients with ACLF receiving plasma adsorption plus PE therapy. RCA method might offer an alternative anticoagulation method for them.