Metabolomic analysis identifies dysregulation of lipid metabolism in the immune clearance phase of chronic hepatitis B patients.

There is an accelerated progression of liver necroinflammation and fibrosis in the liver during the immune clearance (IC) phase of Chronic hepatitis B virus (HBV) infection, which are critical indicators of antiviral treatment for chronic hepatitis B (CHB) infection. This study applied serum metabolomics to identify the potential metabolite biomarkers for differential diagnosis between the CHB immune tolerance (IT) and Immune clearance (IC) phases. A liquid chromatography-mass spectrometry (LC-MS)-based approach was applied to evaluate and compared the serum metabolic profiles of 28 patients in IT phase and 33 patients in IC phase and appropriate statistical methods with MetaboAnalystR 2.0 R package to analyze those metabolites. The differential metabolites between IT and TC groups were classified and the top altered classification were lipids and lipid-like molecules and fatty acyls, clearly indicating that there were differences in the lipid metabolomic profile of HBV-infected patients with IT vs. IR phase. We identified the top 10 potential metabolite biomarkers for differential diagnosis between IT and IR. There were four lipid metabolites among them and the AUC of two of them, octadecadienoyl-sn-glycero-3-phosphocholine and 3-Cycloheptene-l-acetic acid, were 0.983 and 0.933. octadecadienoyl-sn-glycero-3-phosphocholine is Diacylglycerol (18:2n6/18:0) and 3-Cycloheptene-l-acetic acid is hydroxy fatty acids, both of which were associated with lipid metabolism. This study not only provides the potential metabolic biomarkers but also insight into the mechanism of CHB progression during IT clearance phase.

Unfolded protein response inhibits KAT2B/MLKL-mediated necroptosis of hepatocytes by promoting BMI1 level to ubiquitinate KAT2B.

Unfolded protein response (UPR) plays an important role in the pathogenesis of many liver diseases. BMI1 has a liver protection effect, but whether it participates in the regulation of hepatocyte death through UPR is not well defined. Herein, the endoplasmic reticulum stress model was established by inducing hepatocyte line (MIHA) with tunicamycin (TM, 5 µg/ml). Cell counting kit-8 assay and flow cytometry were used to evaluate the viability and apoptosis of hepatocytes. The expression levels of BMI1, KAT2B, and proteins related to UPR (p-eIF2α, eIF2α, ATF4, and ATF6), NF-κB (p65 and p-p65), apoptosis (cleaved caspase-3, bcl-2, and bax) and necroptosis (p-MLKL and MLKL) were determined by Western blot. The relationship between KAT2B and BMI1 was determined by co-immunoprecipitation and ubiquitination assay. The results showed that TM not only promoted UPR, apoptosis, and necroptosis in hepatocytes but also upregulated the expression levels of BMI1 and KAT2B and activated NF-κB pathway. BAY-117082 reversed the effects of TM on viability, apoptosis, NF-κB pathway, and BMI1 but strengthened the effects of TM on KAT2B/MLKL-mediated necroptosis. BMI1 promoted the ubiquitination of KAT2B, and BMI1 overexpression reversed the effects of TM on viability, apoptosis, and KAT2B/MLKL-mediated necroptosis. In summary, overexpression of BMI1 promotes the ubiquitination of KAT2B to block the MLKL-mediated necroptosis of hepatocytes.

Advantages of a Novel Model for Predicting Hepatic Fibrosis in Chronic Hepatitis B Virus Carriers Compared with APRI and FIB-4 Scores.

Background and Aims: Aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) are widely used to assess liver fibrosis in chronic hepatitis B virus (HBV) infection. Currently, the definition of normal alanine aminotransferase (ALT) is controversial. We aimed to examine the diagnostic value of APRI and FIB-4 in chronic HBV carriers with different upper limits of normal (ULNs) for ALT. Methods: 581 chronic HBV carriers were divided into the following four groups based on different ULNs for ALT: chronic HBV carriers I, II, III, and IV. Furthermore, 106 chronic HBV carriers formed an external validation group. Predictive values of APRI and FIB-4 were elucidated using the area under the curve (AUC). A liver fibrosis-predictive model-GPSA (named for its measure of gamma glutamyl transpeptidase, platelet count, HBsAg and albumin) was developed using multivariate logistic regression analysis. Results: In chronic HBV carriers I, the AUCs of APRI and FIB-4 were 0.680 and 0.609 for significant fibrosis and 0.678 and 0.661 for cirrhosis, respectively. The AUCs of GPSA for significant fibrosis in the training group, internal group, and external validation group were 0.877, 0.837, and 0.871, respectively. The diagnostic value of GPSA differed among chronic HBV carriers I, II, III, and IV, with AUCs for significant fibrosis being 0.857, 0.853, 0.868, and 0.905 and AUCs for cirrhosis being 0.901, 0.905, 0.886, and 0.913, respectively. GPSA showed a higher diagnostic value than APRI and FIB-4 for predicting significant fibrosis in the four groups. Conclusions: The GPSA model allows for accurate diagnosis of liver fibrosis in chronic HBV carriers with different ULN for ALT.

[Inhibitory effect of combined transfection of p53 and AS genes on K562 cell proliferation].

This study was aimed to investigate the inhibitory effect of combined transfection of p53 and angiostatin (AS) genes on K562 cells and to explore its mechanism. pVTRIO2-hp53-hAS was transfected into K562 cells with lipofectamine 2000, RT-PCR was used to determine the expression of gene of interest in transfected cells, MTT growth curve and flow cytometry were used to analyze the cell cycle for observation biological changes of cells, the cellular immunochemistry assay was used to observe the expression differences between VEGF, Bcl-2 and Bax proteins. The results indicated that the genes of interest have been transfected and stably expressed, the increase of K562 with genes of interest was slower than that without genes of interest (p<0.05). And the increase of K562 in double gene group was slower than that in p53 and AS groups (0.264+/-0.011 at last day A290 nm; 0.652+/-0.039 at last day A290 nm; 0.604+/-0.017 at last day A290 nm respectively) (p<0.05). After transfection, the expressions of VEGF and Bcl-2 protein decreased, but the expressions of Bax increased. It is concluded that the combined transfection of p53 and AS genes into K562 cells shows more notable and powerful inhibition on proliferation than those transfected with single one gene. The synergistic mechanism of p53 and AS genes may be commonly influenced the pathway of Bcl-2 and Bax expression.