Efficacy, safety, and tolerability of lubiprostone for the treatment of non-alcoholic fatty liver disease in adult patients with constipation: The LUBIPRONE, double-blind, randomised, placebo-controlled study design

Global publication trends and research hotspots of the gut-liver axis in NAFLD: A bibliometric analysis

BACKGROUND

Nonalcoholic Fatty Liver Disease(NAFLD)refers to a spectrum of diseases ranging from simple liver steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Bidirectional cross-talk between the gut-liver axis plays an important role in the pathogenesis of NAFLD. To learn more about the gut-liver axis in NAFLD, this study aims to provide a comprehensive analysis from a bibliometric perspective.

METHOD

Literature related to the gut-liver axis in NAFLD from 1989 to 2022 was extracted from the Web of Science Core Collection. Based on Microsoft Excel, CiteSpace and Vosviewer, we conducted to analyze the number of publications, countries/regions, institutions, authors, journals, references, and keywords.

RESULTS

A total of 1,891 literature since 2004 was included, with the rapid growth of the number of papers on the gut-liver axis in NAFLD annually. These publications were mainly from 66 countries and 442 institutions. Of the 638 authors analyzed, Bernd Schnabl was the one with the most publications, and Patrice D. Cani was the one with the most co-citations. International Journal of Molecular Sciences is the journal with the most articles published, and Hepatology is the journal with the most citations. The most common keywords are gut microbiota, inflammation, and insulin instance, which are current research hotspots. Short-chain fatty acid, in vitro, randomized controlled trial in clinical, and diabetes mellitus represent the research frontiers in this field and are in a stage of rapid development.

CONCLUSION

This is the first study to conduct a comprehensive bibliometric analysis of publications related to the gut-liver axis in NAFLD. This study reveals that gut microbiota, inflammation, insulin resistance, short-chain fatty acids, and randomized controlled trial will be the hotspots and new trends in the gut-liver axis in NAFLD research, which could provide researchers with key research information in this field and is helpful for further exploration of new research directions.

Lubiprostone in patients with non-alcoholic fatty liver disease: a randomised, double-blind, placebo-controlled, phase 2a trial

BACKGROUND

The laxative drug lubiprostone improves intestinal permeability in healthy volunteers. We aimed to assess efficacy and safety of lubiprostone in patients with non-alcoholic fatty liver disease (NAFLD) with constipation via attenuation of intestinal permeability.

METHODS

This randomised, double-blind, placebo-controlled, phase 2a study in Yokohama City University Hospital, Japan, recruited patients (aged 20-85 years) with NAFLD and constipation, alanine aminotransferase (ALT) at least 40 U/L, liver stiffness (≤6·7 kPa), and hepatic fat fraction at least 5·2% when assessed by MRI-proton density fat fraction. Eligible patients were randomly assigned (11:10:9) by a computer-based system and stratified by age and sex to receive 24 μg lubiprostone, 12 μg lubiprostone, or placebo, orally, once per day for 12 weeks. The primary endpoint was the absolute changes in ALT at 12 weeks. Efficacy analysis was done by intention to treat. Safety was assessed in all treated patients. This trial was registered with University Hospital Medical Information Network Clinical Trials Registry (UMIN000026635).

FINDINGS

Between March 24, 2017, and April 3, 2018, we screened 288 patients, of whom 150 (52%) were randomly assigned to treatment: 55 patients were assigned to receive 24 μg lubiprostone, 50 to receive 12 μg lubiprostone, and 45 to receive placebo. A greater decrease in the absolute ALT levels from baseline to 12 weeks was seen in the 24 μg lubiprostone group (mean -13 U/L [SD 19]) than in the placebo group (1 U/L [24]; mean difference -15 U/L [95% CI -23 to -6], p=0·0007) and in the 12 μg lubiprostone group (-12 U/L [21]) than in the placebo group (mean difference -13 U/L [-22 to -5], p=0·0023). 18 (33%) of 55 patients in the 24 μg group had at least one adverse event, as did three (6%) of 47 patients in the 12 μg group and three (7%) of 43 in the placebo group. The most common adverse event was diarrhoea (17 [31%] of patients in the 24 μg group, three [6%] in the 12 μg group, none in the placebo group). No life-threatening events or treatment-related deaths occurred.

INTERPRETATION

Lubiprostone was well tolerated and reduced the levels of liver enzymes in patients with NAFLD and constipation. Further studies are necessary to better define the efficacy and tolerability of lubiprostone in patients with NAFLD without constipation.

FUNDING

Mylan EPD G.K.

Hepatocyte TMEM16A Deletion Retards NAFLD Progression by Ameliorating Hepatic Glucose Metabolic Disorder

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease, and the mechanisms underpinning its pathogenesis have not been completely established. Transmembrane member 16A (TMEM16A), a component of the Ca2+-activated chloride channel (CaCC), has recently been implicated in metabolic events. Herein, TMEM16A is shown to be responsible for CaCC activation in hepatocytes and is increased in liver tissues of mice and patients with NAFLD. Hepatocyte-specific ablation of TMEM16A in mice ameliorates high-fat diet-induced obesity, hepatic glucose metabolic disorder, steatosis, insulin resistance, and inflammation. In contrast, hepatocyte-specific TMEM16A transgenic mice exhibit the opposite phenotype. Mechanistically, hepatocyte TMEM16A interacts with vesicle-associated membrane protein 3 (VAMP3) to induce its degradation, suppressing the formation of the VAMP3/syntaxin 4 and VAMP3/synaptosome-associated protein 23 complexes. This leads to the impairment of hepatic glucose transporter 2 (GLUT2) translocation and glucose uptake. Notably, VAMP3 overexpression restrains the functions of hepatocyte TMEM16A in blocking GLUT2 translocation and promoting lipid deposition, insulin resistance, and inflammation. In contrast, VAMP3 knockdown reverses the beneficial effects of TMEM16A downregulation. This study demonstrates a role for TMEM16A in NAFLD and suggests that inhibition of hepatic TMEM16A or disruption of TMEM16A/VAMP3 interaction may provide a new potential therapeutic strategy for NAFLD.

Amelioration of non-alcoholic steatohepatitis by Qushi Huayu decoction is associated with inhibition of the intestinal mitogen-activated protein kinase pathway

BACKGROUND

Gut microbiota is increasingly recognized as the key participant in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) by translocation of its products, such as lipopolysaccharide (LPS), via the dysfunctional intestinal barrier. Qushi Huayu decoction (QHD), a traditional Chinese medicine, is developed specially for NAFLD and used in clinic in China for more than a decade and previously found to ameliorate non-alcoholic steatohepatitis (NASH) induced by high-fat diet (HFD) in mice accompanied with inhibited metabolic endotoxemia and hepatic LPS signalling.

PURPOSE

To investigate the mechanism of LPS gut-leakage inhibition by QHD in NASH.

METHODS

Effects of QHD on gut microbioa and intestinal barrier were evaluated in NASH induced by HFD in mice. 16S rRNA sequencing is employed to analyse the gut microbiota composition. To identify the potential signalling pathway responsible for tight junction regulation, the colonic phosphoprotein profile is screened via the Phospho Explorer Antibody Array and verified in NASH, intestinal barrier dysfunctional mouse and Caco-2 cells.

RESULTS

QHD ameliorates NASH accompanied with regulating the gut microbiota composition, protecting intestinal tight junctions and inhibiting LPS gut-leakage without decreasing the abundance of identified Gram-negative bacteria. The validated data of phosphorylated proteins suggested that mitogen-activated protein kinase (MAPK) pathway is predominantly responsible for the colonic tight junction regulation by QHD.

CONCLUSION

QHD inhibits LPS gut-leakage in NASH, which is associated with downregulation of intestinal MAPK pathway.