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Abstract Background Acute liver failure (ALF) is a life-threatening disorder that progresses from self-limiting acute liver injury (ALI). Microcirculatory disturbance characterized by sinusoidal hypercoagulation and subsequent massive hypoxic hepatocyte damage have been proposed to be the mechanism by which ALI deteriorates to ALF; however, the precise molecular pathway of the sinusoidal hypercoagulation remains unknown. Here, we analyzed ALI patients and mice models to uncover the pathogenesis of ALI with microcirculatory disturbance. Methods We conducted a single-center retrospective study for ALI and blood samples and liver tissues were analyzed to evaluate the microcirculatory disturbance in ALI patients (n = 120). Single-cell RNA sequencing analysis (scRNA-seq) was applied to the liver from the concanavalin A (Con A)‑induced mouse model of ALI. Interferon-gamma (IFNγ) and tumor necrosis factor-alpha knockout mice, and primary human liver sinusoidal endothelial cells (LSECs) were used to assess the mechanism of microcirculatory disturbance. Results The serum IFNγ concentrations were significantly higher in ALI patients with microcirculatory disturbance than in patients without microcirculatory disturbance, and the IFNγ was upregulated in the Con A mouse model which presented microcirculatory disturbance. Hepatic IFNγ expression was increased as early as 1 hour after Con A treatment prior to sinusoidal hypercoagulation and hypoxic liver damage. scRNA-seq revealed that IFNγ was upregulated in innate lymphoid cells and stimulated hepatic vascular endothelial cells at the early stage of liver injury. In IFNγ knockout mice treated with Con A, the sinusoidal hypercoagulation and liver damage were remarkably attenuated, concomitant with the complete inhibition of CD40 and tissue factor (TF) upregulation in vascular endothelial cells. By ligand-receptor analysis, CD40-CD40 ligand interaction was identified in vascular endothelial cells. In human LSECs, IFNγ upregulated CD40 expression and TF was further induced by increased CD40-CD40 ligand interaction. Consistent with these findings, hepatic CD40 expression was significantly elevated in human ALI patients with microcirculatory disturbance. Conclusion We identified the critical role of the IFNγ-CD40 axis as the molecular mechanism of microcirculatory disturbance in ALI. This finding may provide novel insights into the pathogenesis of ALI and potentially contribute to the emergence of new therapeutic strategies for ALI patients.

Liver cancer is an aggressive cancer associated with a poor prognosis. Development of therapeutic strategies for liver cancer requires fundamental research using suitable experimental models. Recent progress in direct reprogramming technology has enabled the generation of many types of cells that are difficult to obtain and provide a cellular resource in experimental models of human diseases. In this study, we aimed to establish a simple one‐step method for inducing cells that can form malignant human liver tumors directly from healthy endothelial cells using nonintegrating episomal vectors. To screen for factors capable of inducing liver cancer‐forming cells (LCCs), we selected nine genes and one short hairpin RNA that suppresses tumor protein p53 (TP53) expression and introduced them into human umbilical vein endothelial cells (HUVECs), using episomal vectors. To identify the essential factors, we examined the effect of changing the amounts and withdrawing individual factors. We then analyzed the proliferation, gene and protein expression, morphologic and chromosomal abnormality, transcriptome, and tumor formation ability of the induced cells. We found that a set of six factors, forkhead box A3 (FOXA3), hepatocyte nuclear factor homeobox 1A (HNF1A), HNF1B, lin‐28 homolog B (LIN28B), MYCL proto‐oncogene, bHLH transcription factor (L‐MYC), and Kruppel‐like factor 5 (KLF5), induced direct conversion of HUVECs into LCCs. The gene expression profile of these induced LCCs (iLCCs) was similar to that of human liver cancer cells, and these cells effectively formed tumors that resembled human combined hepatocellular–cholangiocarcinoma following transplantation into immunodeficient mice. Conclusion: We succeeded in the direct induction of iLCCs from HUVECs by using nonintegrating episomal vectors. iLCCs generated from patients with cancer and healthy volunteers will be useful for further advancements in cancer research and for developing methods for the diagnosis, treatment, and prognosis of liver cancer.

Summary: Nonalcoholic fatty liver disease (NAFLD) is a chronic metabolic disorder caused by overnutrition and can lead to nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). The transcription factor Forkhead box K1 (FOXK1) is implicated in regulation of lipid metabolism downstream of mechanistic target of rapamycin complex 1 (mTORC1), but its role in NAFLD-NASH pathogenesis is understudied. Here, we show that FOXK1 mediates nutrient-dependent suppression of lipid catabolism in the liver. Hepatocyte-specific deletion of Foxk1 in mice fed a NASH-inducing diet ameliorates not only hepatic steatosis but also associated inflammation, fibrosis, and tumorigenesis, resulting in improved survival. Genome-wide transcriptomic and chromatin immunoprecipitation analyses identify several lipid metabolism-related genes, including Ppara, as direct targets of FOXK1 in the liver. Our results suggest that FOXK1 plays a key role in the regulation of hepatic lipid metabolism and that its inhibition is a promising therapeutic strategy for NAFLD-NASH, as well as for HCC.

Abstract Background Ornithine transcarbamylase deficiency (OTCD) is most common among urea cycle disorders (UCDs), defined by defects in enzymes associated with ureagenesis. Corticosteroid administration to UCD patients, including OTCD patients, is suggested to be avoided, as it may induce life-threatening hyperammonemia. The mechanism has been considered nitrogen overload due to the catabolic effect of corticosteroids; however, the pathophysiological process is unclear. Methods To elucidate the mechanism of hyperammonemia induced by corticosteroid administration in OTCD patients, we analyzed a mouse model by administering corticosteroids to OTCspf−ash mice deficient in the OTC gene. Dexamethasone (DEX; 20 mg/kg) was administered to the OTCspf−ash and wild-type (WT) mice at 0 and 24 h, and the serum ammonia concentrations, the levels of the hepatic metabolites, and the gene expressions related with ammonia metabolism in the livers and muscles were analyzed. Results The ammonia levels in Otcspf−ash mice that were administered DEX tended to increase at 24 h and increased significantly at 48 h. The metabolomic analysis showed that the levels of citrulline, arginine, and ornithine did not differ significantly between Otcspf−ash mice that were administered DEX and normal saline; however, the level of aspartate was increased drastically in Otcspf−ash mice owing to DEX administration (P

The increasing number of patients with fatty liver disease is a major health problem. Fatty liver disease with metabolic dysfunction has been recognized as nonalcoholic fatty liver disease (NAFLD). Although there is no standard therapy for NAFLD, previous reports support the effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors on NAFLD. Recently, fatty liver disease with metabolic dysfunction was proposed to be defined as a novel concept, “metabolic associated fatty liver disease (MAFLD)”, and it was proposed that new criteria for MAFLD diagnosis be established. To clarify the effect of SGLT2 inhibitors on MAFLD, we analyzed the efficacy of tofogliflozin in patients with MAFLD. We conducted a single-center, retrospective study to evaluate the efficacy of tofogliflozin in patients with MAFLD treated at Kyushu University Hospital between 2017 and 2019. Tofogliflozin was used to treat 18 patients with MAFLD. To determine the efficacy of tofogliflozin, we evaluated glucose metabolism, insulin resistance, liver injury, hepatic steatosis, and body composition three and six months after drug initiation. Although our study was a preliminary study because of some limitations (e.g., retrospective, observational, single-arm study, small sample size), we show that tofogliflozin could improve liver injury in patients with MAFLD by improving glucose metabolism and insulin resistance without causing muscle loss.

Acute hepatitis B virus (HBV) infection occasionally progresses to acute liver failure, often with poor prognosis. The appropriate pharmacological approach is yet to be established. Although nucleotide analogs (NA) and corticosteroids are candidates for the treatment of acute HBV infection, their therapeutic effects, especially their effect on HBV clearance, remain unclear. To clarify effects on the HBV clearance of combination therapy of NA and steroid pulse therapy (SPT) for acute HBV infection, we first analyze the effectiveness of this therapy in patients with HBV infection compared with NA monotherapy (NAM). Of the 57 consecutive patients with acute hepatitis B infection from May 2007 to December 2018, we have included 25 patients for this study, whom we followed up until HBV clearance. According to the administration of NA and SPT, we divided patients into two groups (NAM group and NA + SPT group) and compared their results. Of the 25 patients, 10 received NAM, whereas 15 received NA + SPT. There were no appreciable adverse effects related to SPT. The time required for the clearance of HBsAg (76 (43–116) days vs. 26 (14–51) days, p = 0.0418) and HBV-DNA (NAM group vs. NA + SPT group: 180 (83.5–220) vs. 69 (43–136) days, p = 0.0420) was significantly shorter in the NA + SPT group than in the NAM group. The hazard ratio of NA + SPT for the clearance of HBsAg and HBV-DNA were 0.45 (0.19–1.09) and 0.35 (0.14–0.89), respectively. In conclusion, we showed that NA + SPT promoted HBV elimination. These findings support the use of the NA + SPT combination for acute HBV infection without the concern of persistent HBV infection.

Liver fibrosis induces intrahepatic microcirculation disorder and hypoxic stress. Hypoxic stress has the potential for an increase in the possibility of more liver fibrosis and carcinogenesis. Liver biopsy is a standard method that evaluates of intrahepatic hypoxia, however, is invasive and has a risk of bleeding as a complication. Here, we investigated the hypoxia reactive gene expressions in peripheral blood mononuclear cells (PBMC) from chronic liver disease patients to evaluate intrahepatic hypoxia in a non-invasive manner. The subjects enrolled for this study were composed of 20 healthy volunteers (HV) and 48 patients with chronic liver disease (CLD). CLD patients contained 24 patients with chronic hepatitis（CH）and 24 patients with liver cirrhosis (LC). PBMC were isolated from heparinized peripheral blood samples. We measured the transcriptional expression of hypoxia reactive genes and inflammatory cytokines by quantitative RT-PCR. mRNA expression of adrenomedullin (AM), vascular endothelial growth factor A (VEGFA) superoxide dismutase (SOD), glutathione peroxidase (GPx) (p