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Background and aim Elimination of hepatitis B virus (HBV) is infrequently achieved with current therapies. Therefore, more effective anti-HBV therapy is needed. We previously reported that geranylgeranylacetone (GGA) showed anti-hepatitis C virus activity in human hepatoma cells. In this study, we examined the anti-HBV activity of GGA. Methods We used HepG2.2.15.7 cells, PXB cells infected with HBV, Huh7 cells transfected with linear HBV, and PLC/PRF/5 cells as HBV-infected hepatocyte models. After GGA treatment, HBV-related antigen was measured by chemiluminescent immunoassay. HBV-related mRNA was examined by Northern blot. cccDNA and endoplasmic reticulum stress markers were measured by real-time polymerase chain reaction. The activities of HBV promoters and enhancer regions were examined using luciferase vectors. Results After GGA treatment, hepatitis B surface antigen and hepatitis B e antigen secretion was decreased in all HBV-infected hepatocyte models. HBV-related mRNA was also decreased by GGA treatment, although cccDNA levels were not affected. Additionally, the activity of HBV S1 and S2 promoter region and Enhancer 1/Enhancer 2/core promoter region was reduced by GGA treatment. The mRNA expression of the main transcription factors, hepatocyte nuclear factor 3 and 4 and CCAAT/enhancer binding protein, was also decreased. Further, the expression levels of endoplasmic reticulum stress markers were increased by GGA treatment, which reflected the change in HBV-related antigen secretion. Conclusions Geranylgeranylacetone treatment reduces HBV-related protein levels by suppressing comprehensive downregulation of HBV promoter and enhancer activity, which might be caused by decreased hepatic transcription factor expression. GGA treatment may enhance anti-HBV effects in combination with other therapies.

Since the discovery of the senescence-associated secretory phenotype, the role of senescent hepatic stellate cells (HSCs) in hepatocellular carcinoma (HCC) development has gained increasing attention. Similar to cytokines, extracellular vesicles (EVs) are essential for intercellular communication. However, the function of EVs derived from senescent HSCs in HCC progression has not been extensively studied. The aims of the present study were to characterize the EVs derived from senescent HSCs and determine their role in the tumor microenvironment. Cellular senescence was induced in human hepatic stellate cells (HHSteCs) with various concentrations of etoposide. Induction was confirmed using EdU staining and 53BP1 and p21 immunostaining. EVs were isolated by ultracentrifugation and analyzed by nanoparticle tracking analysis. Multiplex immunoassays were used to compare the levels of growth factors secreted from hepatoma cell lines and macrophage cells pretreated with EVs derived from senescent HHSteCs (senescent EVs) with those pretreated with EVs derived from normal cultured HHSteCs (normal EVs). Treatment with 25 μM etoposide for 3 days was the most effective at inducing senescence in HHSteCs. This finding was confirmed by induction of irreversible cell-cycle arrest, upregulation of 53BP1 and p21 expression, and increased SA-β-gal staining. Senescent HHSteCs released increased quantities of EV particles compared with normally cultured HHSteCs. Multiplex analysis revealed that there was no difference between hepatoma cell lines treated with normal EVs and those treated with senescent EVs in growth factor secretion. In contrast, the secretion of epidermal growth factor (EGF) was increased by macrophage cells treated with senescent EVs compared with those treated with normal EVs. Furthermore, senescent EVs did not affect the viability of hepatoma cells but increased the viability of hepatoma cells co-cultured with macrophage cells. In conclusion, the release of EVs from senescent HSCs was higher compared with normal HSCs. Furthermore, senescent EVs promoted HCC development by upregulating EGF secretion from macrophages., Biomedical Reports, 12(4), pp.163-170; 2020

Gut microbiota has been associated with liver cirrhosis and, possibly, hepatic encephalopathy. However, only a few studies have examined the link between mucosa-associated microbiota (MAM) and minimal hepatic encephalopathy (MHE). Our aim was to investigate this relationship. Twenty-four patients with cirrhosis underwent colon biopsies at our institution, between January 2014 and April 2015. Patterns of microbial colonization were examined using 16S rRNA gene sequences. MHE was diagnosed using the Neuropsychological Test. Ten (41.7%) of the 24 patients were diagnosed as having MHE. There was no significant difference in the diversity of gut microbiota by sampling locations between those with and without MHE. However, the diversity of the gut microbiota and the proportion of the genus Bacteroides decreased as a function of declining liver function. We divided patients into those with the highest proportion of the genus Bacteroides (Bacteroides-dominant group; n = 9) and into a Bacteroides non-dominant group (n = 15). In the Bacteroides-dominant group, only 1 patient (11.1%) was diagnosed as having MHE, with the incidence rate of MHE being significantly lower in the Bacteroides-dominant group than in the non-dominant group (p = 0.019). The Child–Pugh score (p = 0.05) and use of proton-pump inhibitors (p = 0.015) were negatively correlated to the proportion of Bacteroides. Furthermore, the proportion of the family Clostridiaceae was significantly higher in the Bacteroides-dominant group than in the non-dominant group (p = 0.078). The decrease in microbial diversity and genus Bacteroides in MAM is a risk factor for MHE in patients with liver cirrhosis.

Background and aims A high serum level of saturated free fatty acids (FFAs) is associated with the development of nonalcoholic fatty liver disease (NAFLD). X-box binding protein-1 (XBP-1) is activated by FFA treatment upon splicing. XBP-1 is a transcription factor induced by the endoplasmic reticulum (ER) stress sensor endoribonuclease inositol-requiring enzyme 1 alpha (IRE1α). However, the role of XBP-1 in NAFLD remains relatively unexplored. Toyocamycin was recently reported to attenuate the activation of XBP-1, possibly by inducing a conformational change in IRE1α. In this study, we examined the effect of toyocamycin on hepatocyte lipoapoptosis and steatosis. We also explored the effects of toyocamycin in a mouse model of NAFLD. Methods Huh-7 cells and isolated rat primary hepatocytes were treated with palmitic acid (PA), which is a saturated FFA, in the presence or absence of toyocamycin. In addition, male C57BL/6J mice were fed a diet rich in saturated fat, fructose, and cholesterol (FFC) for 4 months, after which the effect of toyocamycin was assessed. Results Toyocamycin attenuated FFA-induced steatosis. It also significantly reduced PA-induced hepatocyte lipoapoptosis. In addition, toyocamycin reduced the expression of cytosine-cytosine- adenosine-adenosine-thymidine enhancer-binding protein homologous protein (CHOP), which is a key player in ER stress-mediated apoptosis, as well as its downstream cell death modulator, death receptor 5. In the in vivo study, toyocamycin ameliorated the liver injury caused by FFC-induced NAFLD. It also reduced hepatic steatosis and the expression of lipogenic genes. Conclusions The data we obtained suggest that toyocamycin attenuates hepatocyte lipogenesis and ameliorates NAFLD in vivo and may therefore be beneficial in the treatment of NAFLD in humans., PLOS ONE, 12(3), e0170591; 2017

Over 30 years have passed since co-infection with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) was first documented in hemophilia patients in Japan. In such cases, the leading cause of mortality is reportedly HCV-associated end-stage liver disease. However, the current characteristics of hemophilia patients co-infected with HIV/HCV are unknown. The aim of the present study was to reveal the current characteristics, notably HCV geno-prevalence and liver function, among hemophilia patients co-infected with HIV/HCV in Japan. Current characteristics were evaluated using cross-sectional retrospective data of 44 hemophilia patients positive for anti-HCV and anti-HIV antibodies who underwent screening of liver dysfunction. A total of 56.8% of hemophilia patients co-infected with HIV/HCV were positive for HCV RNA. The most common HCV genotypes were 1a, 1b and 3a. Liver cirrhosis was diagnosed in 26.3% patients negative for HCV RNA and 60.0% patients positive for HCV RNA. Decompensated liver cirrhosis was diagnosed in 33.3% HCV RNA-positive patients and none of the HCV RNA-negative patients. The rate of liver cirrhosis was greater for HCV genotype 3a compared with other genotypes. Overall, the current primary HCV RNA genotypes among hemophilia patients co-infected with HIV/HCV are 1a, 1b and 3a. Over 50% of HIV/HCV co-infected hemophilia patients positive for HCV RNA were diagnosed with liver cirrhosis and some were diagnosed with decompensated liver cirrhosis., Experimental and Therapeutic Medicine, 15(2), pp.2148-2155; 2018

Protein denaturalization in the aqueous solution of surfactant was discussed by measuring the degree of the inhibition of invertase activity. Evaluation of the human skin-roughness was performed by the dropping method and the immersion method. A strong correlation was observed between the inhibition o invertase activity by surfactants and the skin-roughness. This screening method is an excellently valuable selecting mild surfactans for skin.