Excess fructose enhances oleatic cytotoxicity via reactive oxygen species production and causes necroptosis in hepatocytes.

Non-alcoholic fatty liver disease (NAFLD), the hepatic phenotype of metabolic syndrome, has been identified as a major health concern as the number of cirrhosis and deaths associated with NAFLD is expected to increase. Although fructose intake has been considered to be a progressive factor in the pathophysiology of NAFLD, it remains unclear how fructose contributes to hepatocellular damage during lipotoxicity. In the present study, we aimed to analyze the hepatotoxicity of fructose in steatosis. Fructose effects on lipotoxicity were evaluated in HepG2 cells, primary mouse hepatocytes, and in mice fed a high-fat diet with or without sucrose (HFDS/HFD). Oleate induced caspase 3-independent cell death in HepG2 cells and primary mouse hepatocytes cultured in fructose-supplemented medium, and induced cleavage of caspase-1 in primary mouse hepatocytes. In addition, the number of cells stained positive for reactive oxygen species (ROS) was significantly increased, and N-acetyl cysteine was found to inhibit ROS production and cell death. Cell death was confirmed to be through necrotic cell death, and phosphorylation of mixed lineage kinase domain-like (MLKL) protein was observed. Taken together, hepatocyte cytotoxicity was due to excess fructose with oleate-induced ROS-mediated necroptosis. HFDS mice showed progressive hepatic fibrosis and inflammation and a higher NAS score than HFD mice or mice fed a control diet. The expression of hemoxygenase-1, phosphorylation of MLKL, cleavage of caspase1, and apoptosis were significantly increased in the livers of mice fed a HFDS. Overall, excess fructose intake induces necroptosis through the production of ROS and enhances the toxicity of oleatic cytotoxicity.

Serum alpha-fetoprotein increases prior to fibrosis resolution in a patient with acute liver failure.

A 78-year-old woman who was diagnosed with acute liver failure due to an undetermined cause presented with liver atrophy. Coagulopathy was normalized at 35 days of hospitalization, although atrophy in the liver persisted. During the observation period, alpha-fetoprotein (AFP) bi-modally increased at 36 and 377 days. Around the second peak of AFP, the liver volume was regained within the normal range. Fucosylated AFP was found at the first peak but not at the second peak. Cytokines/chemokines were simultaneously evaluated, and the results were evaluated using PANTHER ( http://www.pantherdb.org/ ). Although transaminase and prothrombin time were within the normal range, cytokines/chemokines associated with angiogenesis and inflammation increased prior to the second peak of AFP. Our study suggests that the first peak of AFP occurs in response to acute insult, while the second peak may be associated with the resolution of liver fibrosis. The present case provides new insights into the mechanism of AFP elevation.

Impact of Grip Strength in Patients with Unresectable Hepatocellular Carcinoma Treated with Lenvatinib.

Although sarcopenia is characterized by a loss of muscle strength and skeletal muscle mass, few studies have evaluated the effect of muscle strength on hepatocellular carcinoma (HCC) patients. We evaluated the impact of sarcopenia-related factors (grip strength (GS) and the skeletal muscle index (SMI)) on the survival among lenvatinib-treated unresectable HCC (u-HCC) patients. This single-center cohort study was conducted at a university hospital. The study population included 63 lenvatinib-treated u-HCC patients managed between April 2018 and April 2020. A decreased GS and decreased SMI were found in 21 (33.3%) and 22 (34.9%) patients, respectively. The overall survival (OS) of the normal GS group was significantly higher than that of the decreased GS group, while that of the normal and decreased SMI groups did not differ markedly. There were no significant differences in the progression-free survival between the normal GS and decreased GS groups or the normal SMI and decreased SMI groups. A multivariate Cox proportional hazards model showed that modified albumin-bilirubin-grade (mALBI) 2b (hazard ratio (HR) 4.39) and a decreased GS (HR 3.55) were independently associated with an increased risk of poor prognosis. In addition to the hepatic functional reserve, a decreased GS was a poor prognostic factor in lenvatinib-treated u-HCC patients.

Unfavorable prognosis of patients with acute liver injury due to drug-induced liver injury and acute exacerbation of hepatitis B virus infection.

AIM: Acute liver injury (ALI) has a favorable prognosis, whereas acute liver failure (ALF) leads to organ failure and thus has an unfavorable prognosis. The effect of each etiology on the clinical course of ALI remains unclear. This study aimed to determine how each etiology and glucocorticoid on the unfavorable etiology affects the clinical course of ALI. METHODS: This prospective observational study enrolled 522 patients with ALI/ALF from 2004 and 2017. To evaluate the influence of etiology on prognosis, decision tree analysis was carried out using age, disease type, etiology, and the presence of hepatic encephalopathy. RESULTS: Of 522 patients, 398 patients satisfied the ALI criteria at registration in this study. The ALI etiologies were as follows: viral hepatitis through oral infection (n = 54), acute hepatitis B virus (HBV) infection (n = 24), acute exacerbation of HBV infection (n = 30), de novo hepatitis due to HBV (n = 5), autoimmune hepatitis (n = 59), drug-induced liver injury (DILI; n = 85), other viruses (n = 12), and undetermined (n = 129). ALI in 46 patients progressed to ALF after registration. Of 11 patients (age >52 years) with ALF due to acute exacerbation of HBV infection or DILI, seven patients (63.6%) died. Whether glucocorticoid affected the clinical course of ALI due to acute exacerbation of HBV infection or DILI was evaluated using propensity score matching (age, sex, alanine aminotransferase, total bilirubin, and prothrombin time-international normalized ratio). Glucocorticoid did not improve the prognosis of ALI patients due to the two etiologies. CONCLUSIONS: Progression of ALI due to DILI or acute exacerbation of HBV infection to ALF showed a poor prognosis.

Caspase-independent hepatocyte death: A result of the decrease of lysophosphatidylcholine acyltransferase 3 in non-alcoholic steatohepatitis.

BACKGROUND AND AIMS: Lipotoxicity causes liver inflammation, which leads to non-alcoholic steatohepatitis (NASH). Lysophosphatidylcholine (LPC) is a causal agent of lipotoxicity. Recently, lysophosphatidylcholine acyltransferase (LPCAT) was identified as an enzyme that catalyzes the esterification of LPC, which potentially decreases LPC levels. However, the effect of LPCAT in lipotoxicity of the liver is not fully understood. Our aim was to determine whether LPCAT attenuates lipotoxicity in the liver. METHODS: Mice fed a high-fat diet with sucrose (HFDS) or high-fat diet without sucrose, and Huh-7 cells treated with palmitate were used. RESULTS: Mice-fed HFDS showed advanced liver fibrosis as compared with mice-fed high-fat diet or normal chow. Lysophosphatidylcholine acyltransferase 3 (LPCAT3) mRNA expression in the liver was significantly decreased in the HFDS liver, and LPC content in the HFDS liver was significantly increased as compared with the other groups. When Huh-7 cells with short hairpin RNA-mediated knockdown of LPCAT3 (shLPCAT3 cells) were treated with palmitate, the intracellular LPC concentration and cell death were significantly higher than those in wild-type Huh-7 cells. Palmitate-induced cell death in shLPCAT3 was attenuated by a combination of receptor-interacting protein kinase 1 inhibitor with pan-caspase inhibitor. In contrast, intracellular LPC and palmitate-induced cell death were significantly lower in LPCAT3-overexpressing Huh-7 cells than in wild-type cells. CONCLUSION: Depletion of LPCAT3 in a mouse model of NASH leads to caspase-independent cell death, and LPCAT3 is a potential therapeutic target in NASH.