Zhou-Hua Hou

Polyethylene terephthalate microplastics (PET-MPs) are emerging environmental pollutants, but the molecular mechanisms underlying their hepatotoxicity remain poorly understood. Here, we combined network toxicology with experimental validation to investigate how PET-MPs induce liver injury. In silico, we investigated the PET-repeating unit as the molecular basis for target interactions. We identified 59 overlapping genes between 157 putative PET-MPs targets and 1693 liver injury-associated genes. Protein–protein interaction analysis revealed six hub genes (AKT1, PIK3CA, PIK3CB, PIK3CD, PIK3R1, and SRC), all components of the PI3K/AKT signaling pathway. Gene ontology analysis showed that PET-MPs affect cellular stress responses and kinase activities, while pathway enrichment analysis identified PI3K-Akt, Ras, and reactive oxygen species pathways as primary targets. Molecular docking demonstrated strong binding affinity between PET-MPs and these core targets (binding free energies <−5 kcal/mol). In vitro, PET-MPs induced mitochondrial depolarization, oxidative stress, upregulation of TNF-α and IL-6, and decreased p-AKT/AKT ratio, accompanied by increased apoptosis; the apoptotic effect was reversed by the AKT agonist SC79. In vivo experiments confirmed that AKT activation reduced PET-MP-induced liver injury, evidenced by decreased inflammation, lower serum transaminases, and restored oxidative balance. These protective effects were abolished by PI3K/AKT pathway inhibitors. Our study identifies potential therapeutic targets and strategies for PET-MP-induced liver injury.

Bacterial liver abscess is one of the common infectious diseases of the digestive system. Invasive Klebsiella pneumoniae liver abscess syndrome (IKLAS) refers to cases where, in addition to liver abscess, there are migratory infections foci or other invasive manifestations. The clinical characteristics and risk factors of IKLAS are not fully elucidated, and there is a lack of research on the effectiveness and cost-effectiveness of different treatment methods. This study aims to compare the clinical characteristics of patients with IKLAS and non-IKLAS, and explore effective and economical treatment methods. This retrospective study collected medical records of patients with Klebsiella pneumoniae liver abscess treated at Xiangya Hospital of Central South University from January 2010 to December 2023. A total of 201 patients were included, dividing into an IKLAS group (n=37) and a non-IKLAS group (n=164). Differences in demographics, symptoms and signs, laboratory indicators, imaging characteristics, comorbidities, treatment methods, treatment outcomes, and direct treatment costs between 2 groups were analyzed. The study also compared the effectiveness and costs of different treatment methods. Compared with the non-IKLAS group, the proportion of patients with diabetes, Quick Sequential Organ Failure Assessment (qSOFA)≥2, immune deficiency, anemia, and thrombocytopenia in the IKLAS group was higher, and the level of procalcitonin at the onset in the IKLAS group was also higher (all PPPPPPP<0.05). Patients with IKLAS have poorer prognosis and higher direct medical costs. The combination of abscess puncture and drainage or surgery has a higher improvement rate and lower hospitalization costs compared to antibiotics alone, suggesting that surgical intervention may reduce antibiotic costs and save medical expenses.

Background: Acute liver failure (ALF) is a syndrome of severe hepatocyte injury with high rate of mortality. Hepatitis B virus (HBV) infection is the major cause of ALF worldwide, however, the underlying mechanism by which HBV infection leads to ALF has not been fully disclosed. Methods: D-GalN-induced hepatocyte injury model and LPS/D-GalN-induced ALF mice model were used to investigate the effects of HBV X protein (HBx) in vitro and in vivo, respectively. Cell viability and the levels of Glutathione (GSH), malondialdehyde (MDA) and iron were measured using commercial kits. The expression of ferroptosis-related molecules were detected by qRT-PCR and western blotting. Epigenetic modification and protein interaction were detected by chromatin immunoprecipitation (ChIP) assay and co-immunoprecipitation (co-IP), respectively. Mouse liver function was assessed by measuring aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The histological changes in liver tissues were monitored by hematoxylin and eosin (H&E) staining, and SLC7A11 immunoreactivity was assessed by immunohistochemistry (IHC) analysis. Results: D-GalN triggered ferroptosis in primary hepatocytes. HBx potentiated D-GalN-induced hepatotoxicity and ferroptosis in vitro, and it suppressed SLC7A11 expression through H3K27me3 modification by EZH2. In addition, EZH2 inhibition or SLC7A11 overexpression attenuated the effects of HBx on D-GalN-induced ferroptosis in primary hepatocytes. The ferroptosis inhibitor ferrostatin-1 (Fer-1) protected against ALF and ferroptosis in vivo. By contrast, HBx exacerbates LPS/D-GalN-induced ALF and ferroptosis in HBx transgenic (HBx-Tg) mice. Conclusion: HBx facilitates ferroptosis in ALF via EZH2/H3K27me3-mediated SLC7A11 suppression.

To study the effect of micro (mi)RNA on cellular proliferation induced by hepatitis B x protein, HBx, in human liver cells and to investigate the underlying molecular mechanism of this cancer-related effect. The human L02 hepatocyte cell line was stably transfected with HBx (L02/HBx) or an HBx mutant (L02/HBx-d382) that induces higher levels of cellular proliferation. The differential miRNA expression profiles were determined by microarray analysis and confirmed by real-time PCR. Two miRNAs, miR-338-3p and miR-551b, that were found to be significantly down-regulated in the L02/HBx-d382 cells were selected for further study and transfected individually into cells using the lipofectamine procedure. The cell survival rate was analyzed by MTT assay, and cell cycles were assessed by flow cytometry. Expressions of cyclinD1, cyclinG1, and E2F1 were assessed by real-time PCR and Western blotting. Compared with the microarray miRNA profile of L02/pcDNA3.0 cells, six miRNAs were up-regulated and five miRNAs were down-regulated in the L02/HBx-d382 cells, while four miRNAs were up-regulated and 12 were down-regulated in the L02/HBx cells. The microarray results were consistent with real-time PCR results. Transfection of miR-338-3p and miR-551b significantly inhibited the cell survival rates (P less than 0.001) and induced G0/G1 phase cycle arrest. According to MTT results: for L02/HBx-d382 cells, compared with lipofectamine or non-transfected (NC) controls, the t value of miR-338-3p was 10.402, 9.133 and the t value of miR-551b was 8.763, 7.403; for L02/HBx cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 9.105, 8.074 and the t value of miR-551b was 7.673, 7.52. According to flow cytometry results: for L02/HBx-d382 cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 12.173, 11.107 and the t value of miR-551b was 15.364, 13.377; for L02/HBx cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 15.416, 13.378, and the t value of miR-551b was 13.276, 13.109. The protein levels of cyclinD1, cyclinG1, and E2F1 were significantly reduced by both miR-338-3p and miR-551b ( P less than 0.001). For L02/HBx-d382 cells, compared with lipofectamine or NC controls: E2F1 had t = 11.132, 10.031 and 12.017, 10.973, respectively; cyclinD1 had t = 15.654, 15.013 and 15.447, 14.733, respectively; cyclinG1 had t = 8.017, 7.661 and 7.402, 7.417, respectively. For L02/HBx cells, compared with lipofectamine or NC controls: E2F1 had t = 14.244, 13.331 and 15.022, 14.468, respectively; cyclinD1 had t = 8.695, 8.137 and 7.877, 7.503, respectively; cyclinG1 had t = 7.73, 7.471 and 7.596, 7.41, respectively. In contrast, the mRNA levels for E2F1, cyclinD1, and cylcinG1 showed no significant differences between the miRNA transfected cells and controls. Wild-type HBx and the high proliferation-inducing mutant HBx can influence the miRNA expression profile of L02 cells. HBx down-regulates miR-338-3p and miR-551b in L02 cells, and the high proliferation-inducing mutant has a more robust effect. The mechanism of miR-338-3p- or miR-551b-mediated cell growth inhibition appears to be related to the direct modulation of cyclinD1, cyclinG1, and E2F1.