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Ren F.,Beijing Institute of Liver Disease
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology

To determine the mechanism underlying the therapeutic activities of glycogen synthase kinase 3b (GSK3b) against hepatic ischemia-reperfusion (H-IR) injury by investigating the inhibitive effects of GSK3b on inflammation mediated by Toll-like receptor 4 (TLR4). C57BL/6 male mice were subjected to 90 min of warm liver cephalad lobe ischemia, followed by reperfusion for various lengths of time. The mice were divided into three groups: the H-IR untreated model (control group), and the H-IR inflammation-induced models that received an intraperitoneal injection of purified lipopolysaccharide (LPS) endotoxin alone (inflammation group) or with pretreatment of the SB216763 GSK3b-specific inhibitor (intervention group). To create a parallel isolated cell system for detailed investigations of macrophages, marrow-derived stem cells were isolated from femurs of the H-IR control group of mice and used to derive primary macrophages. The cells were then divided into the same three groups as the whole mouse system: control, LPS-induced inflammation model, and inflammation model with SB216763 intervention. Differential expressions of inflammation-related proteins and genes were detected by Western blotting and real-time quantitative PCR, respectively. The phosphorylation levels of ERK, JNK and p38 MAPK were induced in liver at 1 h after reperfusion, but then steadily decreased and returned to baseline levels by 4 h after reperfusion. In addition, the phosphorylation levels of ERK and JNK were induced in macrophages at 15 min after LPS stimulation, while the phosphorylation level of p38 MAPK was induced at 1 h; SB216763 pretreatment suppressed the LPS-stimulated ERK, JNK and p38 phosphorylation in macrophages. In the mouse model, GSK3b activity was found to promote the gene expression of anti-inflammatory cytokine IL-10 (control: 0.21 ± 0.08, inflammation: 0.83 ± 0.21, intervention: 1.76 ± 0.67; F = 3.16, P = 0.027) but to significantly inhibit the gene expression of pro-inflammatory cytokines IL-12 (control: 0.11 ± 0.05, inflammation: 0.85 ± 0.11, intervention: 0.43 ± 0.10; F = 2.67, P = 0.038), TNF-a, (control: 0.052 ± 0.012, inflammation: 8.11 ± 0.98, intervention: 3.9 ± 0.82; F = 4.13, P = 0.016), IL-6 (control: 0.22 ± 0.08, inflammation: 6.37 ± 0.81, intervention: 2.11 ± 0.63; F = 3.21, P = 0.024), and IL-1b (control: 0.12 ± 0.07, inflammation: 2.51 ± 0.62, and intervention: 1.28 ± 0.33; F = 2.22, P = 0.030). Inhibition of GSK3b selectively regulates the expression of anti-inflammatory and pro-inflammatory cytokines in liver Kupffer cells (liver macrophages). This process may be one of the mechanisms underlying the ability of GSK3b to ameliorate hepatic ischemia-reperfusion injury, possibly because inhibition of pro-inflammatory cytokines may indirectly mediate liver cell apoptosis. Source

Yuan L.,Capital Medical University | Liu A.,Capital Medical University | Qiao L.,Beijing Institute of Liver Disease | Sheng B.,Capital Medical University | And 3 more authors.
BioMed Research International

Although HAD is now rare due to HAART, the milder forms of HAND persist in HIV-infected patients. HIV-induced systemic and localized inflammation is considered to be one of the mechanisms of HAND. The levels of cytokines in CSF were associated with neurocognitive impairment in HIV infection. However, the changes of cytokines involved in cognition impairment in plasma have not been shown, and their relationships between CSF and plasma require to be addressed. We compared cytokine levels in paired CSF and plasma samples from HIV-infected individuals with or without neurocognitive impairment. Cytokine concentrations were measured by Luminex xMAP. In comparing the expression levels of cytokines in plasma and CSF, IFN-α2, IL-8, IP-10, and MCP-1 were significantly higher in CSF. Eotaxin was significantly higher in plasma, whereas G-CSF showed no difference between plasma and CSF. G-CSF (P=0.0079), IL-8 (P=0.0223), IP-10 (P=0.0109), and MCP-1 (P=0.0497) in CSF showed significant difference between HIV-CI and HIV-NC group, which may indicate their relationship to HIV associated neurocognitive impairment. In addition, G-CSF (P=0.0191) and IP-10 (P=0.0377) in plasma were significantly higher in HIV-CI than HIV-NC. The consistent changes of G-CSF and IP-10 in paired plasma and CSF samples might enhance their potential for predicting HAND. Copyright © 2015 Lin Yuan et al. Source

Shi Y.,Capital Medical University | Wei F.,Capital Medical University | Wei F.,Beijing Institute of Liver Disease | Hu D.,Dalian Medical University | And 6 more authors.
Journal of Medical Virology

Hepatitis B virus (HBV) can evolve by mutations in the major hydrophilic region (MHR) of the HBV surface antigen (HBsAg) to permit its escape from neutralization by antibodies such as HBV surface antibody (anti-HBs) and from host immune responses. This study investigated the prevalence and pattern of MHR mutations in North China and the clinical correlations of these mutations. The MHRs of 161 HBsAg-positive patients were amplified using nested PCR, and directly sequenced to identify MHR mutations. It was showed that among the 161 patients infected with HBV genotype C in North China, the overall frequency of MHR mutation was 46.6%. Furthermore, MHR mutations were associated with high white blood cell counts (P=0.025), high bilirubin levels (P=0.048), and cirrhosis (P=0.010). The most frequent mutations in patients with both HBsAg-positive and anti-HBs-positive were located in subregion 1 and 3 of MHR, specifically, residue Q101 (29.9%) and I126 (70.6%), which was different from the mutation pattern found in Western Europe and the United States. Taken together, these data indicated important virological and clinical aspects of HBV evolution in terms of the surface gene of genotype C, which might be important for its response to the currently available HBV vaccine. © 2012 Wiley Periodicals, Inc. Source

Jin R.,Capital Medical University | Sun Y.,Capital Medical University | Qi X.,Chinese PLA General Hospital | Zhang H.,Capital Medical University | And 5 more authors.
DNA Repair

The X-ray repair cross complementing group 1 (XRCC1) protein is involved in DNA base excision repair and its expression varies during the cell cycle. Although studies have demonstrated that rapid XRCC1-dependent single-strand break repair (SSBR) takes place specifically during S/G 2 phases, it remains unclear how it is regulated during the cell cycle. We found that XRCC1 is a direct regulatory target of E2F1 and further investigated the role of XRCC1 in DNA repair during the cell cycle. Saos2 primary osteosarcoma cells stably transfected with inducible E2F1-wt or mutant E2F1-132E were treated with hydroxurea (HU) for 36h and were subsequently withdrawn HU for 2-24h to test whether cell-cycle-dependent DNA SSBR requires E2F1-mediated upregulation of XRCC1. We found that SSBR activity, as determined using a qPCR-base method, was correlated with E2F1 levels at different phases of the cell cycle. XRCC1-positive (AA8) and negative (EM9) CHO cells were used to demonstrate that the alterations in SSBR were mediated by XRCC1. The results indicate that E2F1-mediated regulation of XRCC1 is required for cell-cycle-dependent SSBR predominantly in G 1/S phases. Our observations have provided new mechanistic insight for understanding the role of E2F1 in the maintenance of genomic stability and cell survival during the cell cycle. The regulation of XRCC1 by E2F1 during cell-cycle-dependent SSBR might be an important aspect for practical consideration for resolving the problem of drug resistance in tumor chemotherapies. © 2011 Elsevier B.V. Source

Ma J.,Beijing Institute of Liver Disease | Ma J.,Beijing Baihuirui Bio Technologies Inc | Zhang Y.,Beijing Baihuirui Bio Technologies Inc | Chen X.,Capital Medical University | And 9 more authors.

The role of preexisting minority drug-resistance mutations in treatment failure has not been fully understood in chronic hepatitis B patients. To understand mechanisms of drug resistance, we analyzed drug-resistance mutations in 46 treatment-failure patients and in 29 treatment-naïve patients and determined linkage patterns of the drug-resistance mutations in individual viral genomes using a highly sensitive parallel allele-specific sequencing (PASS) method. Lamivudine resistance (LAMr) mutations were predominant in treatment-failure patients, irrespective of the inclusion of LAM in the regimen. The primary LAMr mutations M204V and M204I were detected in 100% and 30% of the treatment-failure patients, respectively. Two secondary LAMr mutations (L180M and V173L) were also found in most treatment-failure patients (87% and 78%, respectively). The linkages containing these three mutations dominated the resistant viruses. Importantly, minority LAMr mutations present in <2% of the viral population were detected in 83% of the treatment-naïve patients. Moreover, the low-frequency same linked LAMr mutations (<0.15%) were detected in 24% of the treatment-naïve patients. Our results demonstrate that the selection of preexisting minority linked LAMr mutations may be an important mechanism for the rapid development of LAM resistance, caution the continuous use of LAM to treat drug-experienced and -naïve hepatitis B patients, and underline the importance of the detection of minority single and linked drug-resistance mutations before initiating antiviral therapy. © 2013 Ma et al. Source

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