Lay Summaries - Volume 69 Issue 5
Lay Summary: Direct-acting antivirals are an effective tool for the treatment of hepatitis C virus, enabling the elimination of the virus. However, some patients who have been successfully treated with direct-acting antivirals are at risk of reinfection. Our findings showed that the risk of reinfection was highest among people with recent injection drug use. Among people who inject drugs, daily use of opioid-agonist therapy was associated with a lower risk of reinfection.
Lay Summary: This study assesses the changes to structure, blood flow and perfusion that occur in the key organs (liver, spleen and kidney) associated with severe liver disease (Compensated Cirrhosis), using magnetic resonance imaging. The magnetic resonance imaging measures which changed with disease severity and were related to negative liver-related clinical outcomes are described.
Lay Summary: Chimeric animals are composed of cells from different species. Chimeric animals carrying human tissue have the potential to increase the availability of transplantable organs. We transplanted rat-to-mouse liver grafts into newly weaned rats. The chimeric grafts underwent post-transplant remodelling with rat hepatocytes replacing all mouse hepatocytes within 56 days. In addition, we observed the post-transplant development of diffuse mature rat bile ducts through the transformation of hepatocytes, and patchy areas of portal endothelium originating from the host. These data demonstrate the efficacy of transplanting rat-to-mouse chimeric livers into rats, with a high potential for post-transplant graft remodelling.
Lay Summary: Ex vivo liver resection and autotransplantation were performed in a large series of patients with end-stage hepatic alveolar echinococcosis. The results showed that this surgical option was feasible, with acceptable postoperative mortality, but 100% disease-free survival in survivors. Careful patient selection, as well as precise assessment for size and quality of the remnant liver are key to successful surgery.
Lay Summary: Multiple organ failures, ranging from 1–6, are common in hospitalized patients with cirrhosis. The survival without liver transplant is dismal in the presence of three or more organ failures. Small retrospective studies have shown that liver transplant is feasible with good outcomes even in the presence of multiple organ failures. In this study, using a large national dataset, we show that survival chances for more than 30?days in those with three or more organ failures are less than 8%. However, if a liver transplant is performed quickly, the survival chances are very high with one-year survival ranging from 84% with three organ failures to 81% with 5–6 organ failures.
Lay Summary: Sorafenib is approved as the standard therapy for patients with advanced hepatocellular carcinoma, but only provides limited survival benefit. Herein, we found that inhibition of the kinase ERK2 increases the response to sorafenib in liver cancer. Our data indicate that a combination of sorafenib and a MEK inhibitor is most likely to be effective in tumors with high basal phospho-ERK levels.
Lay Summary: PAGE-B scores and Toronto HCC risk index were developed to predict the risk of hepatocellular carcinoma (HCC) in Caucasian patients with CHB under potent antiviral therapy. This study validated these two scores in Asian patients with CHB and suggested that modified PAGE-B scores could improve the predictive performance. A modified PAGE-B score, which is based only on a patient’s age, gender, baseline platelet counts, and serum albumin levels at treatment initiation, represents a reliable and easily available risk score to predict HCC development during the first five years of antiviral treatment in Asian patients with CHB. With a scoring range from 0 to 21 points, a modified PAGE-B score differentiates the HCC risk. A modified PAGE-B score significantly differentiates the five-year HCC risk: low =8 points and high =13 points.
Lay Summary: Glycogen storage disease type Ia (GSD1a) is a rare metabolic disease characterized by hypoglycemia, steatosis, excessive glycogen accumulation and tumor development in the liver. In this study, we have observed that GSDIa livers reprogram their metabolism in a similar way to cancer cells, which facilitates tumor formation and progression, in the absence of hepatic fibrosis. Moreover, hepatic burden due to overload of glycogen and lipids in the cells leads to a decrease in cellular defenses, such as autophagy, which could further promote tumorigenesis in the case of GSDI.
Lay Summary: Most patients with hepatitis C virus have been treated or will be treated with direct-acting antivirals. It is important that we can model the risk of hepatocellular carcinoma in these patients, so that we develop the optimum screening strategy that avoids unnecessary screening, while adequately screening those at increased risk. Herein, we have developed and validated models that are available as web-based tools that can be used to guide screening strategies.
Lay Summary: Activation of the nuclear bile acid receptor FXR regulates gene expression networks, controlling lipid, cholesterol and glucose metabolism, which are mostly effective after eating. Whether FXR exerts critical functions during fasting is unknown. The results of this study show that FXR transcriptional activity is regulated by the glucagon/protein kinase A and the FOXA2 signaling pathways, which act on FXR through phosphorylation and protein-protein interactions, respectively, to increase hepatic glucose synthesis.
Lay Summary: The protein CARD6 plays an important role during the process of liver blood flow restriction (ischemia) and restoration (reperfusion). By suppressing the activity of ASK1, CARD6 can protect against hepatocyte injury. Targeting CARD6 is a potential strategy for prevention and treatment of ischemia/reperfusion injury.
Lay Summary: Primary biliary cholangitis is a liver disease in which most patients have antibodies to mitochondrial proteins containing lipoic acid binding site(s). This paper identified a man-made chemical present in soils around a waste site. It was then shown that this chemical was metabolized into a product with structural similarity to lipoic acid, which was capable of replacing lipoic acid in mitochondrial proteins.
Lay Summary: Biliary atresia is a severe inflammatory and obstructive disease of bile ducts occurring in infancy. Although the cause is unknown, activation of the innate and adaptive immune systems injures the bile duct epithelium. In this study we found that patients’ livers had increased expression of inflammasome genes. Using mice engineered to inactivate individual inflammasome genes, the epithelial injury and bile duct obstruction were prevented by the loss of Il1r1 or Nlrp3, with a decreased activation of natural killer cells and expression of cytokines and chemokines. In contrast, the loss of Casp1 did not change the disease phenotype. Combined, the findings point to a differential role of inflammasome gene products in the pathogenic mechanisms of biliary atresia.
Lay Summary: Disease severity in alcoholic liver disease (ALD) is associated with a significant presence of neutrophils (a type of immune cell) in the liver. It remains unknown how alcohol affects the capacity of neutrophils to control infection, a major hallmark of ALD. We found that binge alcohol drinking impaired important strategies used by neutrophils to contain and resolve infection, resulting in increased liver injury during ALD.
Lay Summary: In patients with non-alcoholic fatty liver disease, participation in structured lifestyle programs may be jeopardized by job and time constraints. A web-based intervention may be better suited for young, busy patients, and for those living far from liver units. The study shows that, following a structured motivational approach, a web-based, interactive intervention coupled with six-month face-to-face meetings is not inferior to a standard group-based intervention with respect to weight loss, adherence to healthy diet and habitual physical activity, normalization of liver enzymes, and stable surrogate markers of fibrosis.