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Chen L.-Y.,Harbin Medical University | Yang B.,Harbin Medical University | Zhou L.,Capital Medical University | Ren F.,Capital Medical University | And 3 more authors.
Molecular Medicine Reports | Year: 2015

Hepatocyte apoptosis and energy metabolism in mitochondria have an important role in the mechanism of acute liver failure (ALF). However, data on the association between apoptosis and the energy metabolism of hepatocytes are lacking. The current study assessed the activity of several key enzymes in mitochondria during ALF, including citrate synthase (CS), carnitine palmitoyltransferase-1 (CPT-1) and cytochrome c oxidase (COX), which are involved in hepatocyte energy metabolism. A total of 40 male Sprague-Dawley rats were divided into five groups and administered D-galactosamine and lipopolysaccharide to induce ALF. Hepatic pathology and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling examinations indicated that hepatocyte apoptosis was observed at 4 h and increased 8 h after ALF. Hepatocyte necrosis appeared at 12 h and was significantly higher at 24 h with inflammatory cell invasion. The results measured by electron microscopy indicated that ultrastructural changes in mitochondria began at 4 h and the mitochondrial outer membrane was completely disrupted at 24 h resulting in mitochondrial collapse. The expression of CS, CPT-1 and COX was measured and analyzed using assay kits. The activity and protein expression of CS, CPT-1 and COX began to increase at 4 h, reached a peak at 8 h and decreased at 12 h during ALF. The activities of CS, CPT-1 and COX were enhanced during hepatocyte apoptosis suggesting that these enzymes are involved in the initiation and development of ALF. Therefore, these results demonstrated that energy metabolism is important in hepatocyte apoptosis during ALF and hepatocyte apoptosis is an active and energy-consuming procedure. The current study on how hepatocyte energy metabolism affects the transmission of death signals may provide a basis for the early diagnosis and development of an improved therapeutic strategy for ALF. Source

Liu Z.,Capital Medical University | Zhang Y.,Capital Medical University | Wei F.,Beijing Institute of Hepatology | Xu M.,Capital Medical University | And 5 more authors.
Epidemiology and Infection | Year: 2016

Hepatitis G virus or GB virus C (GBV-C) is a human virus of the Flaviviridae family that is structurally and epidemiologically closest to hepatitis C virus, but replicates primarily in lymphocytes. Co-infection with GBV-C has been reported to confer beneficial outcomes in some HIV-positive patients. Up to now, however, studies on GBV-C infection in the central nervous system (CNS) of HIV-infected patient have rarely been reported. Herein, we report on a 32-year-old HIV-1-infected patient with cerebral toxoplasmosis and fungal encephalitis. GBV-C viral loads were detected in CSF by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), and the results showed that GBV-C viral load was 6 5 log copies/ml. We amplified and sequenced the E2 and 5′-untranslated regions from the purified viral RNA from CSF by RT-PCR. Both sequences belong to genotype 3 and there were some minor nucleotide divergence among the E2 sequences from the CSF of the patient. These data suggest that GBV-C may be able to penetrate the blood-brain barrier and colonize the CNS of HIV-infected patients. However, the exact mechanisms and potential effect of the infected GBV-C in CNS on HIV-associated neuropathy needs to be further explored. © Cambridge University Press 2015. Source

Li X.,Capital Medical University | Gou C.,Capital Medical University | Yang H.,Capital Medical University | Qiu J.,Capital Medical University | And 3 more authors.
Scandinavian Journal of Gastroenterology | Year: 2014

Objective. This study aimed to investigate the protective effects of echinacoside, one of the phenylethanoids isolated from the stems of Cistanche salsa, a Chinese herbal medicine, on D-galactosamine (GalN) and lipopolysaccharide (LPS)-induced acute liver injury in mice. Methods. We administered GalN (650 mg/kg) together with LPS (30 μg/kg) to mice by intraperitoneal injection to induce acute liver damage. Echinacoside (60 mg/kg) was given intraperitoneally to mice at 1 h prior to GalN/LPS exposure. Mice were sacrificed at different time points following GalN/LPS treatment, and the liver and blood samples were collected for future analysis. Results. It showed that GalN/LPS treatment produced severe hepatic injury, evidenced by significantly elevated plasma alanine aminotransferase (ALT) levels and abnormal histological changes such as hepatocyte necrosis or apoptosis, hemorrhage, fatty degeneration, and neutrophil infiltration. Notably, pretreatment with echinacoside remarkably improved the survival rate of GalN/LPS-treated mice and attenuated acute hepatotoxicity, as demonstrated by decreased ALT levels and improved histological signs. Echinacoside shows both anti-apoptotic and anti-inflammatory properties, characterized by a substantial inhibition of hepatocyte apoptosis and a significant reduction in the inflammatory markers, including myeloperoxidase, extracellular nucleosomes, high-mobility group box 1, and inflammatory cytokines in the plasma of mice, which may be important mechanisms related to its protective effect. Conclusion. Our results suggest that echinacoside can provide a pronounced protection against GalN/LPS-induced acute liver injury in mice, which may complement the available strategies for management of acute liver damage in clinical settings. © 2014 Informa Healthcare. Source

Wen Z.,Tongji University | Wen Z.,Shanghai University | Liu Y.,Capital Medical University | Li F.,Baylor College of Medicine | And 7 more authors.
Journal of Cellular Biochemistry | Year: 2013

Circulating histones are a newly recognized mediator implicated in various inflammatory diseases. It is likely that the release of histones, from dying hepatocytes or inflammatory leukocytes, into the circulation initiates and amplifies inflammation during the course of acute liver failure (ALF). In this study, we investigated a putative pathogenic role of circulating histones in a murine model of ALF induced by D-galactosamine (GalN) plus lipopolysaccharide (LPS). Hepatic function and histological indexes, myeloperoxidase (MPO) activity, hepatocyte apoptosis and the levels of circulating histone were measured in GalN/LPS-treated mice. GalN/LPS caused severe liver damage and a notable increase in plasma concentration of circulating histones. To further assess the role of circulating histones in our model, we administered exogenous histones and anti-histone H4 antibody. Notably, exogenous histones aggravated GalN/LPS-induced hepatotoxicity, whereas anti-histone antibody significantly protected mice. Circulating histones may serve as both a functional marker of ALF activity and as an inflammatory mediator contributing to the progression of ALF. Blockade of circulating histones shows potent protective effects, suggesting a potential therapeutic strategy for ALF. J. Cell. Biochem. 114: 2384-2391, 2013. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc. Source

Shi Y.,Capital Medical University | Shi Y.,Beijing Institute of Hepatology | Han Y.,University of Jinan | Xie F.,Beijing Institute of Hepatology | And 8 more authors.
Journal of Cellular and Molecular Medicine | Year: 2015

Inactivation of p53-mediated cell death pathways is a central component of cancer progression. ASPP2 (apoptosis stimulated protein of p53-2) is a p53 binding protein that specially stimulates pro-apoptosis function of p53. Down-regulation of ASPP2 is observed in many human cancers and is associated with poor prognosis and metastasis. In this study, ASPP2 was found to enhance L-OHP-induced apoptosis in HCT116 p53-/- cells in a p53-independent manner. Such apoptosis-promoting effect of ASPP2 was achieved by inhibiting autophagy. Further experiments with ASPP2 RNA interference and autophagy inhibitor (3-methyladenine, 3-MA) confirmed that ASPP2 enhanced HCT116 p53-/- cell apoptosis via inhibiting the autophagy. The association of cell death and autophagy was also found in ASPP2+/- mice, where colon tissue with reduced ASPP2 expression displayed more autophagy and less cell death. Finally, colorectal tumours and their adjacent normal tissues from 20 colorectal cancer patients were used to examine ASPP2 expression, p53 expression and p53 mutation, to understand their relationships with the patients' outcome. Three site mutations were found in p53 transcripts from 16 of 20 patients. ASPP2 mRNA expressions were higher, and autophagy level was lower in the adjacent normal tissues, compared with the tumour tissues, which was independent of both p53 mutation and expression level. Taken together, ASPP2 increased tumour sensitivity to chemotherapy via inhibiting autophagy in a p53-independent manner, which was associated with the tumour formation, suggesting that both p53 inactivation and ASPP2 expression level were involved in the sensitivity of colorectal cancer to chemotherapy. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine. Source

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