Hepatic sinusoidal obstruction syndrome (HSOS) is a hepatic vascular disease presenting with abdominal distension, pain in the hepatic region, ascites, jaundice, and hepatomegaly. In China, this disease is often associated with the oral intake of plants that contain pyrrolidine alkaloids. The existing guidelines are limited to HSOS associated with hematopoietic stem cell transplantation in Western countries. The Hepatobiliary Diseases Committee of the Chinese Society of Gastroenterology convened an expert consensus conference on the diagnosis and treatment of PA–HSOS to evaluate current research in China and abroad. The “Nanjing criteria” developed by the committee to diagnose PA–HSOS include a confirmed history of PA‐containing plant use and (i) abdominal distention and/or pain in the hepatic region, hepatomegaly, and ascites; (ii) elevation of serum total bilirubin or abnormal laboratory liver tests; (iii) evidence on enhanced computed tomography or magnetic resonance imaging; or (iv) pathological evidence that rules out other known causes of liver injury. Supportive symptomatic treatment, anticoagulant therapy, and placement of a transjugular intrahepatic portosystemic shunt for patients who do not respond to medical treatment are effective for the treatment of PA–HSOS. The benefits of glucocorticoids and prostaglandin E1 in PA–HSOS are not clear.

Glutamine metabolism plays an essential role in cell growth, and glutamate dehydrogenase (GDH) is a key enzyme. GDH promotes the metabolism of glutamate and glutamine to generate ATP, which is profoundly increased in multiple human cancers. Through in vitro and in vivo experiments, we verified that the small-molecule GDH inhibitor EGCG slowed the progression of fibrosis by inhibiting GDH enzyme activity and glutamine metabolism. SIRT4 is a mitochondrial enzyme with NAD that promotes ADP ribosylation and downregulates GDH activity. The role of SIRT4 in liver fibrosis and the related mechanisms are unknown. In this study, we measured the expression of SIRT4 and found that it was downregulated in liver fibrosis. Modest overexpression of SIRT4 protected the liver from fibrosis by inhibiting the transformation of glutamate to 2-ketoglutaric acid (α-KG) in the tricarboxylic acid cycle (TCA), thereby reducing the proliferative activity of hepatic stellate cells (HSCs). Collectively, our study reveals that SIRT4 controls GDH enzyme activity and expression, targeting glutamine metabolism in HSCs and alleviating liver fibrosis.

Liver fibrosis is a reversible disease course caused by various liver injury etiologies, and it can lead to severe complications, such as liver cirrhosis, liver failure, and even liver cancer. Traditional pharmacotherapy has several limitations, such as inadequate therapeutic effect and side effects. Nanotechnology in drug delivery for liver fibrosis has exhibited great potential. Nanomedicine improves the internalization and penetration, which facilitates targeted drug delivery, combination therapy, and theranostics. Here, we focus on new targets and new mechanisms in liver fibrosis, as well as recent designs and development work of nanotechnology in delivery systems for liver fibrosis treatment.

Background and Aim: Hepatic encephalopathy (HE) is a serious complication of decompensated liver cirrhosis, affecting the prognosis of patients underwent transjugular intrahepatic portosystemic shunts (TIPS). We aim to create a nomogram to predict hepatic encephalopathy- free survivals (HEFS) after TIPS in cirrhotic patients and select appropriate candidates for TIPS. Methods: Cirrhotic patients underwent TIPS from 2015 to 2018 in our department were included. Multivariable Cox regression was conducted to estimate the predictors of overt HE (OHE) after TIPS within one year. A nomogram based on the Cox proportional hazard model using data from a retrospective training cohort (70% of the patients) was developed. Then the prediction model was validated in the remaining 30% patients by Harrell’s C-indexes, ROC curves and calibration plots. Results: Of 373 patients, 117 developed postoperative OHE (31.4%). The training and validation groups comprised 83 (31.4%) and 34 (31.2%) patients, respectively. The cumulative survival rates of patients with HE at 1, 2 and 3 years were 90%, 83% and 76%, respectively. The nomogram included the following variables: age, Child-Turcotte-Pugh class (CTP class), diabetes mellitus (DM), serum creatinine and serum sodium (C-index = 0.772). The C-index for HEFS prediction was 0.773 for the validation cohort. The ROC for predicting HEFS was 0.809 and 0.783, respectively. Conclusions: We created a nomogram of predicting postoperative HEFS in cirrhotic patients received TIPS. This nomogram could be an important tool of HE risk prediction before TIPS to guide the therapeutic strategy in cirrhotic patients.

The intestinal-liver axis is associated with various liver diseases. Here, we verified the role of the gut microbiota and macrophage activation in the progression of pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome (PA-HSOS), and explored the possible mechanisms and new treatment options. The HSOS murine model was induced by gavage of monocrotaline (MCT). An analysis of 16S ribosomal DNA (16S rDNA) of the feces was conducted to determine the composition of the fecal microbiota. Macrophage clearance, fecal microbiota transplantation (FMT), and butyrate supplementation experiments were used to assess the role of intestinal flora, gut barrier, and macrophage activation and to explore the relationships among these three variables. Activated macrophages and low microflora diversity were observed in HSOS patients and murine models. Depletion of macrophages attenuated inflammatory reactions and apoptosis in the mouse liver. Moreover, compared with control-FMT mice, the exacerbation of severe liver injury was detected in HSOS-FMT mice. Specifically, butyrate fecal concentrations were significantly reduced in HSOS mice, and administration of butyrate could partially alleviated liver damage and improved the intestinal barrier in vitro and in vivo. Furthermore, elevated lipopolysaccharides in the portal vein and high proportions of M1 macrophages in the liver were also detected in HSOS-FMT mice and mice without butyrate treatment, which resulted in severe inflammatory responses and further accelerated HSOS progression. These results suggested that the gut microbiota exacerbated HSOS progression by regulating macrophage M1 polarization via altered intestinal barrier function mediated by butyrate. Our study has identified new strategies for the clinical treatment of HSOS.