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The proto-oncogene MYCN expression marked a cancer stem-like cell population in hepatocellular carcinoma (HCC) and served as a therapeutic target of acyclic retinoid (ACR), an orally administered vitamin A derivative that has demonstrated promising efficacy and safety in reducing HCC recurrence. This study investigated the role of MYCN as a predictive biomarker for therapeutic response to ACR and prognosis of HCC. MYCN gene expression in HCC was analyzed in the Cancer Genome Atlas and a Taiwanese cohort (N = 118). Serum MYCN protein levels were assessed in healthy controls (N = 15), patients with HCC (N = 116), pre- and post-surgical patients with HCC (N = 20), and a subset of patients from a phase 3 clinical trial of ACR (N = 68, NCT01640808). The results showed increased MYCN gene expression in HCC tumors, which positively correlated with HCC recurrence in non-cirrhotic or single-tumor patients. Serum MYCN protein levels were higher in patients with HCC, decreased after surgical resection of HCC, and were associated with liver functional reserve and fibrosis markers, as well as long-term HCC prognosis (>4 years). Subgroup analysis of a phase 3 clinical trial of ACR identified serum MYCN as the risk factor most strongly associated with HCC recurrence. Patients with HCC with higher serum MYCN levels after a 4-week treatment of ACR exhibited a significantly higher risk of recurrence (hazard ratio 3.27; p = .022). In conclusion, serum MYCN holds promise for biomarker-based precision medicine for the prevention of HCC, long-term prognosis of early-stage HCC, and identification of high-response subgroups for ACR-based treatment.
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Biomarcadores Tumorais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína Proto-Oncogênica N-Myc , Recidiva Local de Neoplasia , Proto-Oncogene Mas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/patologia , Proteína Proto-Oncogênica N-Myc/genética , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/sangue , PrognósticoRESUMO
AIM: The noninvasive tests (NITs) Agile 3+ and Agile 4 effectively identify patients with nonalcoholic fatty liver disease (NAFLD) complicated with advanced fibrosis (F3-4) and cirrhosis (F4), respectively. Little information is available on associations between Agile scores and intra-/extrahepatic events. The aim of this study was to determine the predictive performance of Agile scores for intra-/extrahepatic events in Asian patients with biopsy-proven NAFLD. METHODS: We undertook a retrospective multicenter cohort study to investigate associations between intra-/extrahepatic events and two Agile scores, Agile 3+ and Agile 4. The scores were obtained by combining clinical parameters and liver stiffness measurement using transient elastography. RESULTS: Among 403 enrolled patients, 11 had liver-related events (LREs), including seven with hepatocellular carcinoma (HCC). The incidence of LREs and HCC showed a stepwise increase in the advanced fibrosis group (F3-4), Agile 3+ rule-in (F3-4, highly suspected), and Agile 4 rule-in (F4, highly suspected) groups, compared to their counterparts. Hazard ratios for LREs in the advanced fibrosis group, Agile 3+ rule-in, and Agile 4 rule-in groups were 4.05 (p = 0.03), 23.5 (p = 0.003), and 45.5 (p < 0.001), respectively. The predictive performance results for Agile 3+ and Agile 4 were 0.780 and 0.866, respectively, which were higher than for fibrosis (0.595). Unlike for LREs, Agile scores failed to identify patients with extrahepatic events, including cardiovascular events and extrahepatic cancer. CONCLUSIONS: Agile 3+ and Agile 4 scores are excellent NITs for predicting LREs in patients with NAFLD, possibly without histological assessment.
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AIM: Agile 3+ and Agile 4 scores, based on liver stiffness measurement (LSM) by transient elastography and clinical parameters, were recently reported to be effective in identifying advanced fibrosis and cirrhosis in nonalcoholic fatty liver disease (NAFLD). This study aimed to validate the utility of these scores in Japanese patients with NAFLD. METHODS: Six hundred forty-one patients with biopsy-proven NAFLD were analyzed. The severity of liver fibrosis was pathologically evaluated by one expert pathologist. The LSM, age, sex, diabetes status, platelet count, and aspartate aminotransferase and alanine aminotransferase levels were used to calculate Agile 3+ scores, and the parameters above excluding age were used for Agile 4 scores. The diagnostic performance of the two scores was evaluated using receiver operating characteristic (ROC) curve analysis. Sensitivity, specificity, and predictive values of the original low cut-off (for rule-out) value and high cut-off (for rule-in) value were tested. RESULTS: For diagnosis of fibrosis stage ≥3, the area under the ROC (AUROC) was 0.886, and the sensitivity of the low cut-off value and the specificity of the high cut-off value were 95.3% and 73.4%, respectively. For diagnosis of fibrosis stage 4, AUROC, the sensitivity of the low cut-off value, and the specificity of the high cut-off value were 0.930, 100%, and 86.5%, respectively. Both scores had higher diagnostic performance than the FIB-4 index and the enhanced liver fibrosis score. CONCLUSIONS: Agile 3+ and Agile 4 are reliable noninvasive tests to identify advanced fibrosis and cirrhosis in Japanese NAFLD patients with adequate diagnostic performance.
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AIM: This study aimed to evaluate the real-world efficacy and safety of 12-week sofosbuvir/velpatasvir (SOF/VEL) treatment for patients with decompensated liver cirrhosis caused by hepatitis C virus (HCV) infection. METHODS: A total 72 of patients with Child-Pugh (CP) class B or C were enrolled. We evaluated the sustained virologic response at 12 weeks after the end of treatment (SVR12), adverse events (AEs), and changes in the liver function. RESULTS: All participants had genotype 1 or 2 HCV infection. At baseline, the numbers of patients with CP class B and C were 59 and 13, respectively. The overall SVR12 rate was 95.8% (69/72); 94.9% (56/59) in CP class B and 100% (13/13) in CP class C. The serum albumin level, prothrombin time and ascites were significantly improved (P < 0.01); however, the serum bilirubin level and encephalopathy did not improve. Among patients who achieved SVR12, 75.0% showed an improvement in their CP score, while 5.9% showed a worsening. The presence of large portosystemic shunt (diameter ≥6 mm) and hyperbilirubinemia (≥2.0 mg/dL) were independent factors that interfered with the improvement in the CP score (P < 0.05). The most common AEs were encephalopathy (15.3%) and skin symptoms (7.9%). Two patients discontinued SOF/VEL due to AEs. CONCLUSIONS: Treatment with SOF/VEL for 12 weeks was relatively safe and effective for patients with decompensated cirrhosis. An SVR provided an improvement of the liver function in the majority of patients. However, large portosystemic shunt and hyperbilirubinemia were independent factors that interfered with the improvement in the CP score.
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Oxidative stress is involved in the pathophysiology of nonalcoholic fatty liver disease (NAFLD). However, reliable biomarkers of NAFLD in relation to oxidative stress are not available. While paraoxonase 1 (PON1) is an antioxidant biomarker, there appears to be mixed data on PON-1 in patients with NAFLD. The aim of this meta-analysis was to assess the current data on PON1 activity (i.e., paraoxonase and arylesterase) in patients with NAFLD. A PubMed, CENTRAL, and Embase search identified 12 eligible articles. In the meta-analysis, the paraoxonase activity was low in patients with NAFLD (mean difference (MD) -27.17 U/L; 95% confidence interval (CI) -37.31 to -17.03). No difference was noted in the arylesterase activity (MD 2.45 U/L; 95% CI -39.83 to 44.74). In a subgroup analysis, the paraoxonase activity was low in biopsy-proven nonalcoholic steatohepatitis (MD -92.11 U/L; 95% CI -115.11 to -69.11), while the activity in NAFLD as diagnosed by ultrasonography or laboratory data was similar (MD -2.91 U/L; 95% CI -11.63 to 5.80) to that of non-NAFLD. In summary, the PON1, especially paraoxonase, activity could be a useful biomarker of NAFLD. Further studies are warranted to ascertain the relevance of PON1 measurements in patients with NAFLD.
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Arildialquilfosfatase/metabolismo , Hepatopatia Gordurosa não Alcoólica/enzimologia , Arildialquilfosfatase/genética , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologiaRESUMO
The clinical and virologic features of hepatitis E virus (HEV) infection seem to vary among regions even in developed countries. However, we have little information on the diversity of HEV infection. Here, we investigated the characteristics of 26 patients in our hospital located in Tochigi prefecture, 90 km north of Tokyo, between 2000 and 2019. The reported number of patients with acute hepatitis E is increasing in Japan because measurement of IgA-class anti-HEV antibody was commercially available from 2011. In contrast, the numbers at our hospital were 1.5/y and 1.0/y in 2000 to 2011 and 2012 to 2019, respectively. This is attributed to the fact that we have been investigating HEV as a cause of unknown hepatitis before 2011. Among isolated HEV subgenotypes, including 3a, 3b, 4b, 4c, and 4d, all three patients with subgenotype 4c infection presented acute liver failure. Four HEV strains shared more than or equal to 99% identity within the 412-nucleotide partial sequence, in which the time and place of HEV infection varied, except for one intrafamilial infection. In addition, some strains were similar to HEV strains isolated far from Tochigi prefecture. In conclusion, the number of patients with acute hepatitis E was not increasing at Jichi Medical University Hospital and some strains were found to circulate in Japan.
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BACKGROUND: Chronic liver disease (CLD) is often complicated by severe thrombocytopenia (platelet count < 50,000/µL). Platelet transfusion has been a gold standard for increasing the platelet count to prevent hemorrhagic events in such patients. Lusutrombopag, a thrombopoietin receptor agonist, can increase the platelet count in such patients when invasive procedures are scheduled. Former studies on lusutrombopag included patients with a platelet count of > 50,000/µL at baseline: the proportions of patients who did not require platelet transfusion were 84-96%, which might be overestimated. METHODS: The efficacy and safety of lusutrombopag were retrospectively investigated in CLD patients with platelet count of < 50,000/µL, a criterion for platelet transfusion, in real-world settings. We examined the proportion of patients who did not require platelet transfusion in 31 CLD patients, which exceeded a minimum required sample size (21 patients) calculated by 80% power at a significance level of 5%. Lusutrombopag, 3 mg once daily, was administered 8-18 days before scheduled invasive procedures. RESULTS: Among 31 patients who received lusutrombopag, 23 patients (74.2%) patients showed a platelet count of ≥ 50,000/µL (Group A) and did not require platelet transfusion. The remaining 8 patients (25.8%) did not reached platelet ≥ 50,000/µL (Group B). The means of platelet increase were 38,000/µL and 12,000/µL in groups A and B, respectively. A low platelet count at baseline was a characteristic of patients in group B. Among 13 patients who repeatedly used lusutrombopag, lusutrombopag significantly increased the platelet count as the initial treatment. When all repeated uses of lusutrombopag were counted among these 13 patients, platelet transfusion was not required in 82.1% (23/28) of treatments. Although one patient showed portal thrombosis after lusutrombopag treatment, the thrombosis was disappeared by anticoagulant treatment for 35 days. The degree of platelet increase with lusutrombopag was larger than that in their previous platelet transfusion. CONCLUSIONS: The proportion of patients who did not require platelet transfusion was 74.2%, which is smaller than that in former studies which included CLD patients with a platelet count of > 50,000/µL. However, lusutrombopag is effective and safe for CLD patients with a platelet count of < 50,000/µL.
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Hepatopatias , Trombocitopenia , Cinamatos , Humanos , Hepatopatias/complicações , Hepatopatias/terapia , Receptores de Trombopoetina , Estudos Retrospectivos , Tiazóis , Trombocitopenia/complicações , Trombocitopenia/terapiaRESUMO
Nonalcoholic steatohepatitis (NASH) is a common cause of liver cirrhosis and hepatocellular carcinoma (HCC). However, effective therapeutic strategies for preventing and treating NASH-mediated liver cirrhosis and HCC are lacking. Cholesterol is closely associated with vascular endothelial growth factor (VEGF), a key factor that promotes HCC. Recent reports have demonstrated that statins could prevent HCC development. In contrast, we have little information on ezetimibe, an inhibitor of cholesterol absorption, in regards to the prevention of NASH-related liver cirrhosis and HCC. In the present study, a steatohepatitis-related HCC model, hepatocyte-specific phosphatase and tensin homolog (Pten)-deficient (PtenΔhep ) mice were fed a high-fat (HF) diet with/without ezetimibe. In the standard-diet group, ezetimibe did not reduce the development of liver tumors in PtenΔhep mice, in which the increase of serum cholesterol levels was mild. Feeding of a HF diet increased serum cholesterol levels markedly and subsequently increased serum levels of VEGF, a crucial component of angiogenesis. The HF diet increased the number of VEGF-positive cells and vascular endothelial cells in the tumors of PtenΔhep mice. Kupffer cells, macrophages in the liver, increased VEGF expression in response to fat overload. Ezetimibe treatment lowered cholesterol levels and these angiogenetic processes. As a result, ezetimibe also suppressed inflammation, liver fibrosis and tumor growth in PtenΔhep mice on the HF diet. Tumor cells were highly proliferative with HF-diet feeding, which was inhibited by ezetimibe. In conclusion, ezetimibe suppressed development of liver tumors by inhibiting angiogenesis in PtenΔhep mice with hypercholesterolemia.
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Inibidores da Angiogênese/farmacologia , Dieta Hiperlipídica/efeitos adversos , Ezetimiba/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Animais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Colesterol/sangue , Modelos Animais de Doenças , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Inflamação/sangue , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/sangue , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/sangue , Neovascularização Patológica/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
AIM: High concentrations of homocysteine are believed to induce lipid synthesis and cell injury through endoplasmic reticulum (ER) stress in metabolic syndrome. However, homocysteine could be used to improve steatohepatitis induced by choline deficiency, in which methyl donors are decreased. The aim of the present study was to clarify the role of the physiological concentration of homocysteine in the development of steatohepatitis induced by choline deficiency. METHODS: Wild-type mice were fed a choline-deficient amino acid-defined (CDAA) diet with or without homocysteine supplementation for 24 weeks. Liver cells isolated from mice were exposed to homocysteine under choline-deficient conditions. RESULTS: Wild-type mice fed the CDAA diet developed steatohepatitis with increased ER stress and decreased S-adenosylmethionine (SAM), a methyl donor. Homocysteine supplementation reduced ER stress and restored hepatic SAM, leading to the improvement of steatohepatitis. In in vitro experiments using primary cultured hepatocytes, the physiological concentration of homocysteine decreased the lipid accumulation and ER stress induced by the choline-deficient conditions. However, hepatocyte death was not induced by a physiological concentration of homocysteine or in choline-deficient medium. Interestingly, tumor necrosis factor (TNF)α promoted hepatocyte death under choline-deficient conditions, which was suppressed by homocysteine supplementation. Hepatic macrophages increased the production of TNFα under choline-deficient conditions whereas supplementation of SAM reduced the TNFα production. CONCLUSIONS: Homocysteine supplementation ameliorates steatohepatitis by reducing ER stress and increasing SAM in mice fed a CDAA diet. These results were opposite to those of previous reports, which showed that homocysteine induced cell injury.
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AIM: The major transmission mode of hepatitis A virus (HAV) in Japan is the fecal-oral route by contaminated foods. In contrast, HAV infection is well documented as a sexually transmitted disease in Europe and North America. The present study was undertaken to determine the full-genome sequence of HAV and trace the transmission route of HAV in Japanese men who have sex with men (MSM). METHODS: In 2018, we encountered three Japanese MSM with acute hepatitis A co-infected with HIV for 4-12 years. Serum samples obtained from these patients were used for HAV full-genome analyses. RESULTS: Isolated HAV strains were segregated into subgenotype IA. The three HAV strains shared 100% identity within the 481-nucleotide partial sequence. The entire nucleotide sequence showed that the three strains were 99.97% similar to each other with only two nucleotide substitutions. At the amino acid level, the three strains differed from each other by only one or two amino acids. All three strains obtained in the present study were >99.6% identical to the 66 reported strains isolated from Taiwan and European countries during 2015-2017. In addition, these 66 strains include the RIVM-HAV16-090 (EuroPride) strain, which has been involved in HAV outbreaks among MSM worldwide. CONCLUSIONS: We determined for the first time the full-genome sequence of HAV isolated from Japanese MSM with acute hepatitis A and found that the strains were identical to those from MSM worldwide. Thus, these HAV strains were imported to Japan from foreign countries through MSM.
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The role of Toll-like receptor (TLR) signaling has attracted much attention in the development of hepatic inflammation and hepatocellular carcinoma (HCC). We herein sought to determine the role of TLRs and responsible cells in steatohepatitis-related HCC. We used hepatocyte-specific Pten-deficient (Pten(Δ) (hep)) mice, which exhibit steatohepatitis followed by liver tumor formation, including HCC. We then generated Pten(Δ) (hep)/Tlr4(-/-) and Pten(Δ) (hep)/Tlr2(-/-) double-mutant mice and investigated the role of macrophages using reconstitution of bone marrow (BM)-derived cells, chemical depletion of macrophages, and isolated macrophages. Tlr4 but not Tlr2 deficiency in the Pten(Δ) (hep) mice suppressed tumor growth as well as hepatic inflammation. Gut sterilization by an antibiotic mixture reduced the portal LPS levels as well as tumor growth in the Pten(Δ) (hep) mice. Tumor growth was also decreased by reconstitution of BM-derived cells to Tlr4(-/-) BM cells. In addition, chemical depletion of macrophages significantly reduced tumor size and numbers. Macrophages expressing Ly6C were increased in number, which was associated with inflammation and tumor progression in the Pten(Δ) (hep) mice. Hepatic macrophages isolated from the Pten(Δ) (hep) mice abundantly expressed the Ly6C gene and produced much more IL-6 and TNFα in response to LPS. These proinflammatory cytokines induced the proliferation of HCC cells as well as oval cells, putative cancer progenitor cells. Indeed, putative cancer progenitor cells emerged before the development of macroscopic liver tumors and then increased in number under sustained inflammation. TLR4 on macrophages contributes to the development of steatohepatitis-related HCC in mice.
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Carcinoma Hepatocelular/etiologia , Fígado Gorduroso/complicações , Hepatócitos/patologia , Inflamação/etiologia , Neoplasias Hepáticas/etiologia , Macrófagos/patologia , PTEN Fosfo-Hidrolase/fisiologia , Receptor 2 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Animais , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Feminino , Hepatócitos/metabolismo , Técnicas Imunoenzimáticas , Inflamação/metabolismo , Inflamação/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Transdução de SinaisRESUMO
BACKGROUND: Although several types of diet have been used in experimental steatohepatitis models, comparison of gut microbiota and immunological alterations in the gut among diets has not yet been performed. AIM: We attempted to clarify the difference in the gut environment between mice administrated several experimental diets. METHODS: Male wild-type mice were fed a high-fat (HF) diet, a choline-deficient amino acid-defined (CDAA) diet, and a methionine-choline-deficient (MCD) diet for 8 weeks. We compared the severity of steatohepatitis, the composition of gut microbiota, and the intestinal expression of interleukin (IL)-17, an immune modulator. RESULTS: Steatohepatitis was most severe in the mice fed the CDAA diet, followed by the MCD diet, and the HF diet. Analysis of gut microbiota showed that the composition of the Firmicutes phylum differed markedly at order level between the mice fed the CDAA and HF diet. The CDAA diet increased the abundance of Clostridiales, while the HF diet increased that of lactate-producing bacteria. In addition, the CDAA diet decreased the abundance of lactate-producing bacteria and antiinflammatory bacterium Parabacteroides goldsteinii in the phylum Bacteroidetes. In CDAA-fed mice, IL-17 levels were increased in ileum as well as portal vein. In addition, the CDAA diet also elevated hepatic expression of chemokines, downstream targets of IL-17. CONCLUSIONS: The composition of gut microbiota and IL-17 expression varied considerably between mice administrated different experimental diets to induce steatohepatitis.
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Dieta Hiperlipídica , Microbioma Gastrointestinal , Interleucina-17/imunologia , Intestinos/microbiologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Alanina Transaminase/metabolismo , Animais , Bacteroidetes , Colesterol/metabolismo , Colina , Clostridiales , Dieta , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Feminino , Íleo/imunologia , Intestinos/imunologia , Fígado/patologia , Masculino , Metionina , Camundongos , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Veia Porta , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença , Triglicerídeos/metabolismoRESUMO
Phosphorylated derivatives of phosphatidylinositol, collectively referred to as phosphoinositides, occur in the cytoplasmic leaflet of cellular membranes and regulate activities such as vesicle transport, cytoskeletal reorganization and signal transduction. Recent studies have indicated an important role for phosphoinositide metabolism in the aetiology of diseases such as cancer, diabetes, myopathy and inflammation. Although the biological functions of the phosphatases that regulate phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P(3)) have been well characterized, little is known about the functions of the phosphatases regulating the closely related molecule phosphatidylinositol-3,4-bisphosphate (PtdIns(3,4)P(2)). Here we show that inositol polyphosphate phosphatase 4A (INPP4A), a PtdIns(3,4)P(2) phosphatase, is a suppressor of glutamate excitotoxicity in the central nervous system. Targeted disruption of the Inpp4a gene in mice leads to neurodegeneration in the striatum, the input nucleus of the basal ganglia that has a central role in motor and cognitive behaviours. Notably, Inpp4a(-/-) mice show severe involuntary movement disorders. In vitro, Inpp4a gene silencing via short hairpin RNA renders cultured primary striatal neurons vulnerable to cell death mediated by N-methyl-d-aspartate-type glutamate receptors (NMDARs). Mechanistically, INPP4A is found at the postsynaptic density and regulates synaptic NMDAR localization and NMDAR-mediated excitatory postsynaptic current. Thus, INPP4A protects neurons from excitotoxic cell death and thereby maintains the functional integrity of the brain. Our study demonstrates that PtdIns(3,4)P(2), PtdIns(3,4,5)P(3) and the phosphatases acting on them can have distinct regulatory roles, and provides insight into the unique aspects and physiological significance of PtdIns(3,4)P(2) metabolism. INPP4A represents, to our knowledge, the first signalling protein with a function in neurons to suppress excitotoxic cell death. The discovery of a direct link between PtdIns(3,4)P(2) metabolism and the regulation of neurodegeneration and involuntary movements may aid the development of new approaches for the treatment of neurodegenerative disorders.
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Ácido Glutâmico/toxicidade , Neurônios/citologia , Neurônios/efeitos dos fármacos , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Regulação para Baixo , Discinesias/genética , Discinesias/patologia , Discinesias/fisiopatologia , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Neostriado/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia , Neurônios/enzimologia , Neurônios/patologia , Monoéster Fosfórico Hidrolases/deficiência , Monoéster Fosfórico Hidrolases/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Taxa de Sobrevida , Sinapses/metabolismo , Redução de PesoRESUMO
UNLABELLED: Innate immune signaling associated with Toll-like receptors (TLRs) is a key pathway involved in the progression of nonalcoholic steatohepatitis (NASH). Here we show that both TLR2 and palmitic acid are required for activation of the inflammasome, interleukin (IL)-1α, and IL-1ß, resulting in the progression of NASH. Wild-type (WT) and TLR2(-/-) mice were fed a choline-deficient amino acid-defined (CDAA) diet for 22 weeks to induce NASH. Bone marrow-transplanted TLR2 chimeric mice were generated after the recipient mice were lethally irradiated. Kupffer cells and hepatic stellate cells (HSCs) were isolated from WT mice and stimulated with TLR2 ligand and/or palmitic acid. WT mice on the CDAA diet developed profound steatohepatitis and liver fibrosis. In contrast, TLR2(-/-) mice had suppressed progression of NASH. Although both Kupffer cells and HSCs respond to TLR2 ligand, TLR2 bone marrow chimeric mice demonstrated that Kupffer cells were relatively more important than HSCs in TLR2-mediated progression of NASH. In vitro, palmitic acid alone did not increase TLR2 signaling-target genes, including cytokines and inflammasome components in Kupffer cells and HSCs. The TLR2 ligand increased Nod-like receptor protein 3, an inflammasome component, in Kupffer cells but not in HSCs. In the presence of TLR2 ligand, palmitic acid did induce caspase-1 activation and release of IL-1α and IL-1ß in Kupffer cells; however, these effects were not observed in HSCs. In vivo, WT mice on the CDAA diet showed increased caspase-1 activation in the liver and elevated serum levels of IL-1α and IL-1ß levels, which were suppressed in TLR2(-/-) mice. CONCLUSION: TLR2 and palmitic acid cooperatively activate the inflammasome in Kupffer cells and/or macrophages in the development of NASH.
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Ácido Palmítico/farmacologia , Receptor 2 Toll-Like/fisiologia , Animais , Caspase 1/metabolismo , Fígado Gorduroso , Células Estreladas do Fígado/metabolismo , Inflamassomos , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Células de Kupffer/metabolismo , Cirrose Hepática , Camundongos , Hepatopatia Gordurosa não Alcoólica , Receptor 2 Toll-Like/genéticaRESUMO
We report an autopsy case of advanced esophageal cancer with multiple metastases that presented with a markedly high level of sIL-2R. An 83-year-old man was admitted to our hospital with a 1-week history of epigastric distress, appetite loss, and fatigue. Imaging examinations revealed a large liver tumor. Although the tumor markers for gastrointestinal and liver cancers were within normal limits, the sIL-2R level was extremely high (10,384 U/mL). The patient died immediately after admission due to the rapid course of the disease. An autopsy showed advanced esophageal cancer with multiple metastases, including the liver, lungs, and multiple lymph nodes. In histological examinations, esophageal cancer was a mixture of well- and poorly differentiated squamous cell carcinoma, in which poorly differentiated cancer cells expressed sIL-2R on immunohistochemical staining. However, we failed to detect positive staining for sIL-2R in the lymphocytes. Our findings revealed that solid tumors could express sIL-2R. Although sIL-2R is a tumor marker used for hematological malignancies, such as malignant lymphoma, this case report highlights the value of the measurement of sIL-2R levels in advanced solid tumors, including esophageal cancer. We concluded that sIL-2R has potential as a biomarker in advanced solid tumors for cancer staging and treatment response.
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The role of ferroptosis in steatohepatitis development is largely unknown. We investigated (1) whether hepatocyte ferroptosis occurs in a gene-modified steatohepatitis model without modifying dietary components, (2) whether ferroptosis occurs at an early stage of steatohepatitis, and (3) whether apomorphine, recently reported as a ferroptosis inhibitor, can ameliorate steatohepatitis. Hepatocyte-specific PTEN KO mice were used. Huh 7 and primary cultured hepatocytes isolated from the mice were used in this study. The number of dead cells increased in 10-week-old PTEN KO mice. This cell death was suppressed by the administration of ferroptosis inhibitor ferrostatin-1 for 2 weeks. Apomorphine also ameliorated the severity of steatohepatitis. Treatment with ferroptosis inhibitors, including apomorphine, decreases the level of lipid peroxidase. Apomorphine suppressed cell death induced by RSL-3 (a ferroptosis inducer), which was not suppressed by apoptosis or necroptosis inhibitors. Apomorphine showed a radical trapping capacity with much more potent activity than ferrostatin-1 and Trolox, a soluble form of vitamin E. In addition, apomorphine activated nrf2 and its downstream genes, including HO-1 and xCT. In conclusion, ferroptosis occurs in steatohepatitis from an early stage in PTEN KO mice. In addition, apomorphine ameliorates the severity of steatohepatitis by inhibiting ferroptosis.
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Recent evidence indicates ferroptosis is implicated in the pathophysiology of various liver diseases; however, the organ-specific regulation mechanism is poorly understood. Here, we demonstrate 7-dehydrocholesterol reductase (DHCR7), the terminal enzyme of cholesterol biosynthesis, as a regulator of ferroptosis in hepatocytes. Genetic and pharmacological inhibition (with AY9944) of DHCR7 suppress ferroptosis in human hepatocellular carcinoma Huh-7 cells. DHCR7 inhibition increases its substrate, 7-dehydrocholesterol (7-DHC). Furthermore, exogenous 7-DHC supplementation using hydroxypropyl ß-cyclodextrin suppresses ferroptosis. A 7-DHC-derived oxysterol metabolite, 3ß,5α-dihydroxycholest-7-en-6-one (DHCEO), is increased by the ferroptosis-inducer RSL-3 in DHCR7-deficient cells, suggesting that the ferroptosis-suppressive effect of DHCR7 inhibition is associated with the oxidation of 7-DHC. Electron spin resonance analysis reveals that 7-DHC functions as a radical trapping agent, thus protecting cells from ferroptosis. We further show that AY9944 inhibits hepatic ischemia-reperfusion injury, and genetic ablation of Dhcr7 prevents acetaminophen-induced acute liver failure in mice. These findings provide new insights into the regulatory mechanism of liver ferroptosis and suggest a potential therapeutic option for ferroptosis-related liver diseases.
Assuntos
Ferroptose , Hepatopatias , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Camundongos , Animais , Humanos , Dicloridrato de trans-1,4-Bis(2-clorobenzaminometil)ciclo-hexano , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismoRESUMO
TGF-beta-activated kinase 1 (TAK1) is a MAP3K family member that activates NF-kappaB and JNK via Toll-like receptors and the receptors for IL-1, TNF-alpha, and TGF-beta. Because the TAK1 downstream molecules NF-kappaB and JNK have opposite effects on cell death and carcinogenesis, the role of TAK1 in the liver is unpredictable. To address this issue, we generated hepatocyte-specific Tak1-deficient (Tak1DeltaHEP) mice. The Tak1DeltaHEP mice displayed spontaneous hepatocyte death, compensatory proliferation, inflammatory cell infiltration, and perisinusoidal fibrosis at age 1 month. Older Tak1DeltaHEP mice developed multiple cancer nodules characterized by increased expression of fetal liver genes including alpha-fetoprotein. Cultures of primary hepatocytes deficient in Tak1 exhibited spontaneous cell death that was further increased in response to TNF-alpha. TNF-alpha increased caspase-3 activity but activated neither NF-kappaB nor JNK in Tak1-deficient hepatocytes. Genetic abrogation of TNF receptor type I (TNFRI) in Tak1DeltaHEP mice reduced liver damage, inflammation, and fibrosis compared with unmodified Tak1DeltaHEP mice. In conclusion, hepatocyte-specific deletion of TAK1 in mice resulted in spontaneous hepatocyte death, inflammation, fibrosis, and carcinogenesis that was partially mediated by TNFR signaling, indicating that TAK1 is an essential component for cellular homeostasis in the liver.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Inflamação/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Alanina Transaminase/sangue , Animais , Apoptose , Divisão Celular/fisiologia , Feminino , Deleção de Genes , Hepatócitos/patologia , Hepatócitos/fisiologia , Regeneração Hepática/genética , Masculino , Camundongos , Caracteres SexuaisRESUMO
Background: Both pemafibrate and sodium glucose cotransporter-2 (SGLT2) inhibitor can decrease serum transaminase levels in patients with non-alcoholic fatty liver disease (NAFLD) complicated with dyslipidemia and type 2 diabetes mellitus (T2DM), respectively. However, the effectiveness of combined therapy has been rarely reported. Methods: This is a two-center retrospective observational study. NAFLD patients complicated with T2DM treated with pemafibrate for >1 year were included, in whom prior treatment with SGLT2 inhibitor > 1 year failed to normalize serum alanine aminotransferase (ALT) levels. Hepatic inflammation, function, and fibrosis were assessed by ALT, albumin-bilirubin (ALBI) score, and Mac-2 binding protein glycosylation isomer (M2BPGi) levels, respectively. Results: Seven patients were included. The median duration of prior treatment with SGLT2 inhibitors was 2.3 years. During the one year before starting pemafibrate therapy, the therapy did not significantly change hepatic enzymes. All patients received pemafibrate 0.1 mg twice daily without dose escalations. During one year of pemafibrate therapy, triglyceride, aspartate aminotransferase, ALT, γ-glutamyl transpeptidase, ALBI score, and M2BPGi levels significantly improved (p < 0.05), although weight or hemoglobin A1c did not significantly change. Conclusions: One year of pemafibrate therapy improves markers of hepatic inflammation, function, and fibrosis in NAFLD patients in whom long-term SGLT2 inhibitor therapy failed to normalize serum ALT.