Jiliang He

Emodin Protects Against Concanavalin A-Induced Hepatitis in Mice Through Inhibiting Activation of the p38 MAPK-NF- κB Signaling Pathway

Background/Aims: To investigate the effects of emodin on concanavalin A (Con A)-induced hepatitis in mice and to elucidate its underlying molecular mechanisms. Methods: A fulminant hepatitis model was established successfully by the intravenous administration of Con A (20 mg/kg) to male Balb/c mice. Emodin was administered to the mice by gavage before and after Con A injection. The levels of pro-inflammatory cytokines and chemokines, numbers of CD4+ and F4/80+ cells infiltrated into the liver, and amounts of phosphorylated p38 MAPK and NF-γB in mouse livers and RAW264.7 and EL4 cells were measured. Results: Pretreatment with emodin significantly protected the animals from T cell-mediated hepatitis, as shown by the decreased elevations of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as well as reduced hepatic necrosis. In addition, emodin pretreatment markedly reduced the intrahepatic expression of pro-inflammatory cytokines and chemokines, including tumor necrosis factor (TNF)-a, interferon (IFN)-γ, interleukin (IL)-1ß, IL-6, IL-12, inducible nitric oxide synthase (iNOS), integrin alpha M (ITGAM), chemokine (C-C motif) ligand 2 (CCL2), macrophage inflammatory protein 2 (MIP-2) and chemokine (CXC motif) receptor 2 (CXCR2). Furthermore, emodin pretreatment dramatically suppressed the numbers of CD4+ and F4/80+ cells infiltrating into the liver as well as the activation of p38 MAPK and NF-γB in Con A-treated mouse livers and RAW264.7 and EL4 cells. Conclusion: The results indicate that emodin pretreatment protects against Con A-induced liver injury in mice; these beneficial effects may occur partially through inhibition of both the infiltration of CD4+ and F4/80+ cells and the activation of the p38 MAPK-NF-γB pathway in CD4+ T cells and macrophages.

The evolving story of macrophages in acute liver failure.

Acute liver failure (ALF) remains a worldwide problem. The innate immune system acts as an important regulator of ALF. Kupffer cells (KCs), the resident macrophages in liver, play a key role in liver innate immune response. Recent researches have shown that macrophages display a remarkable plasticity and can differentiate into functionally diverse subsets. However, the dynamic polarized phenotypes and functional status of macrophages at different stage of ALF are not clear. In this paper, we present a review of evidence that KCs play a significant role in the pathogenesis of ALF, including the phenotype and functions of macrophages, signaling pathways involved in macrophage functional status and cell-crosstalks of KCs with other immune cells. More information on macrophages will promote a better understanding of the cellular molecular mechanisms of ALF and provide new insights for the development of therapeutic targets for ALF.

Hypertension and risk of cataract: a meta-analysis.

Background Cataract is the major cause of blindness across the world. Many epidemiologic studies indicated that hypertension might play an important role in the development of cataract, while others not. We therefore conducted this meta-analysis to determine the relationship between risk of cataract and hypertension. Methods Retrieved studies on the association of hypertension with cataract risk were collected from PubMed, Web of Science and the Cochrane Library during June 2014 and were included into the final analysis according to the definite inclusion criteria. Odds ratio (OR) or risk ratio (RR) were pooled with 95% confidence interval (CI) to evaluate the relationship between hypertension and cataract risk. Subgroup analyses were carried out on the basis of cataract type, race and whether studies were adjusted for main components of metabolic syndrome (MS). Results The final meta-analysis included 25 studies (9 cohort, 5 case-control and 11 cross-sectional) from 23 articles. The pooled results showed that cataract risk in populations with hypertension significantly increased among cohort studies (RR 1.08; 95% CI: 1.05–1.12) and case-control or cross-sectional studies (OR 1.28; 95% CI: 1.12–1.45). This association was proved to be true among both Mongolians and Caucasians, and the significance was not altered by the adjustment of main components of MS. Subgroup analysis on cataract types indicated that an increased incidence of posterior subcapsular cataract (PSC) resulted among cohort studies (RR 1.22; 95% CI: 1.03–1.46) and cross-sectional/case-control studies (OR 1.23; 95% CI: 1.09–1.39). No association of hypertension with risk of nuclear cataract was found. Conclusions The present meta-analysis suggests that hypertension increases the risk of cataract, especially PSC. Further efforts should be made to explore the potential biological mechanisms.

Resveratrol Reduces the Proinflammatory Effects and Lipopolysaccharide- Induced Expression of HMGB1 and TLR4 in RAW264.7 Cells

Background: Resveratrol (Res) is a polyphenol anti-inflammatory agent. We have studied the link between the anti-inflammatory effects of Res and the high mobility group box 1(HMGB1) signaling pathway. Methods: Murine macrophage-like RAW264.7 cells (RAW264.7 cells) were either untreated (control) or treated with Res, LPS, or LPS + Res. Levels of IL-6, NO, and TNF-α were measured by ELISA and colorimetric assays. Expression of HMGB1 was detected by qRT-PCR, western blot, and immunofluorescence assays. Protein and mRNA expression levels of TLR4 were also examined. Results: Res significantly reduced the levels of IL-6, NO, and TNF-α in RAW264.7 cells exposed to LPS. Expression levels of HMGB1 (mRNA and protein) and of TLR4 in the LPS + Res-treated cells were lower than in cells treated with LPS alone. Conclusions: Res can block the inflammatory effects induced by LPS in RAW264.7 cells. Down-regulation of HMGB expression may be one of the mechanisms of action of Res. Res may also influence TLR4 expression in the HMGB1-TLR4 signaling pathway.

Shikonin inhibits the lipopolysaccharide-induced release of HMGB1 in RAW264.7 cells via IFN and NF-κB signaling pathways.

To study the anti-inflammation effect of Shikonin (Shik) and its mechanism, murine macrophage-like RAW264.7 cells (RAW264.7 cells) were divided into control group, LPS group (0.125, 0.25 and 0.5μg/ml), LPS (0.125, 0.25 and 0.5μg/ml) plus Shik (0.5, 1 and 2μM) group, and Shik (2μM) group. After exposure for 24h, the levels of Interleukin-6 (IL-6), nitric oxide (NO) and Tumor Necrosis Factor-α (TNF-α) in supernatant were measured with ELISA, the expression of high mobility group box 1(HMGB1) in supernatant and cytoplasm was assayed using qRT-PCR, western blot and immunofluorescence assays, the expression of IFN-β in cellular and supernatant was assayed by qRT-PCR and ELISA, and the ratio of nuclear to cytoplasm for NF-κB protein expression was assayed using western blot. The results of our investigation demonstrated that Shik could reduce significantly the levels of IL-6, NO and TNF-α in RAW264.7 cells exposed to LPS (P<0.05 or P<0.01). The expression of HMGB1, IFN-β and the ratio of nuclear to cytoplasm for NF-κB protein expression in LPS plus Shik group declined significantly as compared with LPS group (P<0.05 or P<0.01). The inhibitors of IFN-β signaling molecule JAK and NF-κB could attenuate significantly the expression of HMGB1 in supernatant. It was found in the present study that Shik could have the anti-inflammatory effects in RAW264.7 cells exposed to LPS, and one of the mechanisms may be the down-regulation of HMGB expression, which was associated with the IFN-β and NF-κB signaling pathways.

Studying the association of microRNA‐210 level with chronic hepatitis B progression

We studied the relationship between hypoxia and microRNA‐210 (miR‐210) levels, the miR‐210 levels in patients with hepatitis B and the roles of miR‐210 in liver inflammation. We used the concanavalin A (Con A) murine hepatitis model and inflammation, hypoxia and miR‐210 levels were examined. In these patients, we studied serum miR‐210 levels and clinical indexes related to hepatitis in 90 patients with different stages of chronic hepatitis B and 30 controls. Two functional assays of miR‐210 in vitro under hypoxic condition were conducted. The animal experiments indicated that the liver and serum miR‐210 levels significantly increased with liver hypoxia and inflammation. In humans, serum miR‐210 levels enhanced with hepatitis severity and were related to serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB) and prothrombin activity (PTA) levels. The miR‐210 functional assays showed that miR‐210 elevation might be related to the decreases in HepG2.2.15 cell dehydrogenase activity and HBV replication under hypoxic conditions. Because the liver inflammation causes liver hypoxia which also results in liver and serum miR‐210 level elevation, the serum miR‐210 level may serve as a molecular biomarker for the severity of hepatitis and increases in liver miR‐210 that we see may be a response of hepatocytes to hypoxia during hepatitis progression.

The effects of hepatitis C virus core protein on the expression of miR-122 in vitro

BackgroundHepatitis C virus (HCV) is one of the major pathogens of liver diseases. Some studies have previously reported that miR-122 can stimulate replication or translation of HCV. However, the effects of HCV infection on miR-122 expression are not clear. The aim of this study was to investigate the effects of HCV core protein on the expression of miR-122 in a cell culture model.ResultsThe miR-122 levels in Huh7.5.1 cells infected with HCV for different days or different HCV abundance were measured by real-time PCR. Significant decrease of miR-122 expression was found at late stage of infection and in the high-abundance group. Huh7.5.1 cells transfected with plasmid pEGFP-core or pEGFP were used to detect the effects of HCV core protein on miR-122 expression, the results showed that core protein could down-regulate the miR-122 expression level in a time- and dose- dependent manner, and reduced the susceptibility of Huh7.5.1 cell to HCV.ConclusionsDown-regulating miR-122 expression by HCV core protein may give a new insight into the interaction between HCV and miR-122 and chronic HCV infection.

Association between Mannose-Binding Lectin Gene Polymorphisms and Hepatitis B Virus Infection: A Meta-Analysis

Objective The results of studies on the relation between Mannose-binding lectin gene (mbl2) polymorphism and HBV infection were contradictory and inconclusive. In order to shed a light on these inconsistent findings and to clarify the role of mbl2 polymorphisms in susceptibility or progression of chronic hepatitis B (CHB), a meta-analysis was performed. Methods PubMed and Embase were searched for available articles. A meta-analysis was performed to examine the association between mbl2 polymorphisms and chronicity or progression of hepatitis B infection. Odds ratio (OR) and its 95% confidence interval (CI) served as indexes. Results A total of 17 eligible studies were involved, including 2151 healthy controls (HC), 1293 spontaneous recovered (SR) patients with acute infection, 2337cases with chronic hepatitis B (CHB) and 554 cases with progressive hepatitis B. There was no evidence of significant association between mbl2 exon1 polymorphisms and CHB risk in any genetic model or pairwise comparisons when compared with HC group or SR group. In the stratified analysis of ethnic groups, also no obvious relation between mbl2 polymorphism and CHB risk was identified. There was still no significant association between the complete mbl2 genotypic profile (including both the exon1 and the promoter gene) polymorphisms and CHB risk, as compared with SR group. However, it was found that there was an association between the mbl2 AO/OO genotype and severe hepatitis B (SHB) or liver cirrhosis (LC) (LC vs. HC:OR=3.66, 95%CI, 2.38-5.63; SHB vs. HC, OR=3.88, 95%CI, 2.26–6.64), but there was no relationship between the mbl2 AO/OO genotype and hepatocellular carcinoma (HCC) (OR=1.26, 95%CI, 0.82-1.94). Conclusion The present meta-analysis indicated that mbl2 exon1 polymorphisms might not significantly associate with chronicity of HBV infection, but might be significantly related to the progressive HBV such as SHB and LC.

Comparing the Curative Effects between Femtosecond Laser-Assisted Cataract Surgery and Conventional Phacoemulsification Surgery: A Meta-Analysis

Purpose To compare the outcomes of femtosecond laser-assisted cataract surgery (FLACS) with those of conventional phacoemulsification surgery (CPS) for age-related cataracts. Methods A comprehensive literature search of PubMed, EMBASE, and the Cochrane Controlled Trials Register was conducted to identify randomized controlled trials (RCT) and comparative cohort studies comparing FLACS with CPS. Endothelial cell loss percentage (ECL%), central corneal thickness (CCT), corrected and uncorrected distant visual acuity (CDVA and UDVA), and mean absolute error (MAE) of refraction were used as primary outcomes. Secondary outcomes included surgically induced astigmatism (SIA), mean effective phacoemulsification time (EPT), phacoemulsification power and circularity of the capsulorhexis. Results Nine RCTs and fifteen cohort studies including 4,903 eyes (2,861 in the FLACS group and 2,072 in the CPS group) were identified. There were significant differences between the two groups in ECL% at one week, about one month and three months postoperatively, in CCT at one day, about one month postoperatively and at the final follow-up, in CDVA at one week postoperatively, and in UDVA at the final follow-up. Significant differences were also observed in MAE, EPT, phacoemulsification power, and the circularity of capsulorhexis. However, no significant differences were observed in CDVA at one week postoperatively or in surgically induced astigmatism. Conclusions Compared to CPS, FLACS is a safer and more effective method for reducing endothelial cell loss and postoperative central corneal thickening as well as achieving better and faster visual rehabilitation and refractive outcomes. However, there is no difference in final CDVA and surgically induced astigmatism between the two groups.

Inhibition effect produced by dominant negative mutant fusion protein PreS2-TLM-ScFv-HBcDN on HBV replication in vitro

Summary.  A mammalian expression vector comprised of the PreS2‐TLM (translocation motif), a single‐chain variable fragment (ScFv) that binds to hepatitis B surface antigen (HBsAg) and the EGFP gene was constructed. A stably transformed cell line that could express and secrete the fusion protein (PreS2‐TLM‐ScFv‐EGFP) was established. HBsAg‐positive HepG2.2.15 cells and HepG2 and HeLa cells were incubated with the supernatant of the transformed cell line cultures for evaluating the cellular permeability of PreS2‐TLM‐ScFv‐EGFP. The location of the fusion protein PreS2‐TLM‐ScFv‐EGFP in HepG2.2.15 cells was observed with immunofluorescence staining. EGFP was next replaced by a dominant negative mutant of the hepatitis B virus core gene (HBcDN) for producing fusion protein PreS2‐TLM‐ScFv‐HBcDN, which was detected by western blot. The supernatant containing fusion protein PreS2‐TLM‐ScFv‐HBcDN was added to the cultures of HepG2.2.15 cells, and the packaged hepatitis B virus (HBV) pregenomic RNA expression levels in the cells were measured using qRT‐PCR. The results of the in vitro study indicated that the packaged HBV pregenomic RNA expression levels in HepG2.2.15 cells significantly decreased when these cells were exposed to the supernatant at the dose of 25% for 24, 48 and 72 h, or at the dose of 12.5% for 72 h.