Efficacy and safety of drugs for nonalcoholic steatohepatitis

Role of 11β-hydroxysteroid dehydrogenase type 1 inhibition in the antiobesity effect of J2H-1702 on adipocytes and a high-fat diet-induced NASH model

Obesity due to excessive body fat accumulation remains a global problem. Patients with obesity have high cortisol levels, and its dysregulation is caused by increased 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) levels. The effects and mechanism of J2H-1702, an 11β-HSD1 inhibitor, on nonalcoholic steatohepatitis (NASH) were explored. This study compared the antiadipogenic effects of J2H-1702, elafibranor (PPARα/δ agonist), and BVT14225 (selective 11β-HSD1 inhibitor) using mouse 3T3-L1 pre-adipocytes. J2H-1702, elafibranor, and BVT14225 inhibited adipocyte differentiation and intracellular lipid accumulation in 3T3-L1 cells by downregulating phospho-extracellular signal-regulated kinase, extracellular signal-regulated kinase, phospho-c-Jun-N-terminal Kinase, c-Jun-N-terminal Kinase, phospho-P38 (P-P38), P38, CCAAT/enhancer-binding proteins alpha and β, peroxisome proliferator-activated receptor γ, and glucocorticoid receptor. Additionally, J2H-1702, elafibranor, and BVT14225 treatments effectively inhibited 11β-HSD1 activity, as revealed by cortisol concentrations, and inhibited cortisone-induced adipocyte differentiation and intracellular lipid accumulation in 3T3-L1 cells. These effects were associated with 11β-HSD1 protein inhibition. Furthermore, J2H-1702 and BVT14225 increased the expression of Akt and phosphoinositide 3-kinase involved in insulin resistance in 3T3L-1 adipocytes. In the LX-2 human hepatic stellate cell line, the relative expression of N-cadherin, 11β-HSD1, collagen1α (COLA1), α-actin of smooth muscle (α-SMA) genes in LX-2 activated with TGF-β increased significantly, and after treatment with J2H-1702, it was significantly reduced. The expression of E-cadherin is decreased in TGF-β-treated LX-2 cells and increased after treatment with J2H-1702. We tested the potential of J2H-1702 as a therapeutic agent for NASH using a high-fat diet-induced NASH model, with obeticholic acid, an FXR agonist, and elafibranor as reference drugs. All drugs significantly decreased the elevated triglyceride levels in the livers of high-fat, high-carbohydrate (HFHC-fed mice. The results may add to the benefits of targeting 11β-HSD1 inhibitors with antiadipogenic activity in developing a therapeutic agent for obesity treatment.

Exploring the potential of drug repurposing for liver diseases: A comprehensive study

Drug repurposing involves the investigation of existing drugs for new indications. It offers a great opportunity to quickly identify a new drug candidate at a lower cost than novel discovery and development. Despite the importance and potential role of drug repurposing, there is no specific definition that healthcare providers and the World Health Organization credit. Unfortunately, many similar and interchangeable concepts are being used in the literature, making it difficult to collect and analyze uniform data on repurposed drugs. This research was conducted based on understanding general criteria for drug repurposing, concentrating on liver diseases. Many drugs have been investigated for their effect on liver diseases even though they were originally approved (or on their way to being approved) for other diseases. Some of the hypotheses for drug repurposing were first captured from the literature and then processed further to test the hypothesis. Recently, with the revolution in bioinformatics techniques, scientists have started to use drug libraries and computer systems that can analyze hundreds of drugs to give a short list of candidates to be analyzed pharmacologically. However, this study revealed that drug repurposing is a potential aid that may help deal with liver diseases. It provides available or under-investigated drugs that could help treat hepatitis, liver cirrhosis, Wilson disease, liver cancer, and fatty liver. However, many further studies are needed to ensure the efficacy of these drugs on a large scale.

Si-Ni-San Reduces Hepatic Lipid Deposition in Rats with Metabolic Associated Fatty Liver Disease by AMPK/SIRT1 Pathway

Background

Metabolic associated fatty liver disease (MAFLD) is a chronic disease characterized by excessive lipid deposition in the liver without alcohol or other clear liver-damaging factors. AMP-activated protein kinase (AMPK)/silencing information regulator (SIRT)1 signaling pathway plays an important role in MAFLD development. Si-Ni-San (SNS), a traditional Chinese medicine, has shown reducing hepatic lipid deposition in MAFLD rats, however, the underlying mechanisms of SNS are barely understood.

Purpose

The aim of this research was to investigate the mechanisms of SNS in reducing hepatic lipid deposition in MAFLD rats by regulating AMPK/SIRT1 signaling pathways.

Methods

The components of SNS were determined by high performance liquid chromatography with mass spectrometry (HPLC-MS) analysis. MAFLD rats were induced by high-fat and high-cholesterol diet (HFHCD), and treated by SNS. SNS-containing serum and Compound C (AMPK inhibitor) were used to treat palmitic acid (PA)-induced HepG2 cells. To elucidate the potential mechanism, lipid synthesis-related proteins (SREBP-1c and FAS), fatty acid oxidation (PPARα and CPT-1), and AMPK/SIRT1 signaling pathway (p-AMPK and SIRT1) were assessed by Western blot.

Results

SNS improved serum lipid levels, liver function and reduced hepatic lipid deposition in MAFLD rats. SNS-containing serum reduced lipid deposition in PA-induced HepG2 cells. SNS could up-regulate protein expressions of PPARα, CPT-1, p-AMPK and SIRT1, and down-regulate protein expressions of SREBP-1c and FAS. Similar effects of SNS-containing serum were observed in PA-induced HepG2 cells. Meanwhile, Compound C weakened the therapeutic effects of SNS-containing serum on lipid deposition.

Conclusion

SNS could reduce hepatic lipid deposition by inhibiting lipid synthesis and promoting fatty acid oxidation, which might be related with activating the AMPK/SIRT1 signaling pathway. This study could provide a theoretical basis for the clinical use of SNS to treat MAFLD.

Combinatorial therapy with BAR502 and UDCA resets FXR and GPBAR1 signaling and reverses liver histopathology in a model of NASH

Non-alcoholic steatosis (NAFLD) and steatohepatitis (NASH) are two highly prevalent human disorders for which therapy remains suboptimal. Bile acids are signaling molecules acting on two main receptors the Farnesoid-x-receptor (FXR) and G protein coupled receptor GPB AR1. Clinical trials have shown that FXR agonism might result in side effects along with lack of efficacy in restoring liver histopathology. For these reasons a multi-targets therapy combined FXR agonists with agent targeting additional molecular mechanisms might have improved efficacy over selective FXR agonists. In the present study we have compared the effects of BAR502, a dual FXR/GPBAR1 ligand) alone or in combination with ursodeoxycholic acid (UDCA) in a model of NAFLD/NASH induced by feeding mice with a Western diet for 10 weeks. The results demonstrated that while BAR502 and UDCA partially protected against liver damage caused by Western diet, the combination of the two, reversed the pro-atherogenic lipid profile and completely reversed the histopathology damage, attenuating liver steatosis, ballooning, inflammation and fibrosis. Additionally, while both agents increased insulin sensitivity and bile acid signaling, the combination of the two, modulated up top 85 genes in comparison of mice feed a Western diet, strongly reducing expression of inflammatory markers such as chemokines and cytokines. Additionally, the combination of the two agents redirected the bile acid metabolism toward bile acid species that are GPBAR1 agonist while reduced liver bile acid content and increased fecal excretion. Together, these data, highlight the potential role for a combinatorial therapy based on BAR502 and UDCA in treating of NAFLD.

Hepatoprotective Effect of Kaempferol: A Review of the Dietary Sources, Bioavailability, Mechanisms of Action, and Safety

The liver is the body's most critical organ that performs vital functions. Hepatic disorders can affect the physiological and biochemical functions of the body. Hepatic disorder is a condition that describes the damage to cells, tissues, structures, and functions of the liver, which can cause fibrosis and ultimately result in cirrhosis. These diseases include hepatitis, ALD, NAFLD, liver fibrosis, liver cirrhosis, hepatic failure, and HCC. Hepatic diseases are caused by cell membrane rupture, immune response, altered drug metabolism, accumulation of reactive oxygen species, lipid peroxidation, and cell death. Despite the breakthrough in modern medicine, there is no drug that is effective in stimulating the liver function, offering complete protection, and aiding liver cell regeneration. Furthermore, some drugs can create adverse side effects, and natural medicines are carefully selected as new therapeutic strategies for managing liver disease. Kaempferol is a polyphenol contained in many vegetables, fruits, and herbal remedies. We use it to manage various diseases such as diabetes, cardiovascular disorders, and cancers. Kaempferol is a potent antioxidant and has anti-inflammatory effects, which therefore possesses hepatoprotective properties. The previous research has studied the hepatoprotective effect of kaempferol in various hepatotoxicity protocols, including acetaminophen (APAP)-induced hepatotoxicity, ALD, NAFLD, CCl₄, HCC, and lipopolysaccharide (LPS)-induced acute liver injury. Therefore, this report aims to provide a recent brief overview of the literature concerning the hepatoprotective effect of kaempferol and its possible molecular mechanism of action. It also provides the most recent literature on kaempferol's chemical structure, natural source, bioavailability, and safety.

Mechanistic Impact of Different Ligand Scaffolds on FXR Modulation Suggests Avenues to Selective Modulators

The bile-acid sensing nuclear farnesoid X receptor (FXR) is an attractive target for the treatment of hepatic and metabolic diseases, but application of this chemotherapeutic concept remains limited due to adverse effects of FXR activation observed in clinical trials. To elucidate the mechanistic basis of FXR activation at the molecular level, we have systematically studied FXR co-regulator interactions and dimerization in response to seven chemically diverse FXR ligands. Different molecular effects on FXR activation mediated by different scaffolds were evident and aligned with characteristic structural changes within the ligand binding domain of FXR. A partial FXR agonist acted mainly through co-repressor displacement from FXR and caused an FXR-regulated gene expression pattern markedly differing from FXR agonist effects. These results suggest selective modulation of FXR dimerization and co-regulator interactions for different ligands, offering a potential avenue for the design of gene- or tissue-selective FXR modulators.

Kinsenoside alleviates inflammation and fibrosis in experimental NASH mice by suppressing the NF-κB/NLRP3 signaling pathway

BACKGROUND

Non-alcoholic steatohepatitis (NASH) has replaced viral hepatitis as the main driver of the rising morbidity and mortality associated with cirrhosis and liver cancer worldwide, while no FDA-approved therapies are currently known. Kinsenoside (KD), naturally isolated from Anoectochilus roxburghii, possesses multiple biological activities, including lipolysis, anti-inflammation, and hepatoprotection. However, the effects of KD on NASH remain unclear.

PURPOSE

This study aimed to explore the roles of KD in NASH and its engaged mechanisms.

METHODS

Two typical animal models of NASH, mice fed a methionine-choline-deficient (MCD) diet (representing non-obese NASH) and mice fed a high-fat and -fructose diet (HFFD) (representing obese NASH), were used to investigate the effect of KD on NASH in vivo. Transcriptome sequencing was performed to elucidate the underlying mechanisms of KD. Lipopolysaccharide (LPS)-stimulated THP-1 cells and transforming growth factor β1 (TGF-β1)-activated LX-2 cells were applied to further explore the effects and mechanisms of KD in vitro.

RESULTS

The intragastric administration of KD remarkably alleviated MCD/HFFD-induced murine NASH almost in a dose-dependent manner. Specifically, KD reduced lipid accumulation, inflammation, and fibrosis in the liver of NASH mice. KD ameliorated alanine aminotransferase (ALT), aspartate aminotransferase (AST), superoxide dismutase (SOD), and malondialdehyde (MDA) abnormalities. In addition, it decreased the level of serum proinflammatory factors (IL-12p70, IL-6, TNF-α, MCP-1, IFN-γ) and the hepatic expression of typical fibrosis-related molecules (α-SMA, Col-I, TIMP-1). Mechanically, KD attenuated the MCD/HFFD-induced NASH through the inhibition of the NF-κB/NLRP3 signaling pathway. Consistently, KD reduced inflammation stimulated by LPS in THP-1 cells via suppressing the NF-κB/NLRP3 pathway. Furthermore, it prevented the activation of LX-2 cells directly, by inhibiting the proliferation stimulated by TGF-β1, and indirectly, by inactivating the NLRP3 inflammasome in macrophages.

CONCLUSION

For the first time, the practical improvement of NASH by KD was revealed. Our study found that KD exerted its alleviative effects on NASH through the inhibition of the NF-κB/NLRP3 signaling pathway. Given its hepatoprotective and nontoxic properties, KD has the potential to be a novel and effective drug to treat NASH.

Pathogenesis and Therapeutic Strategies Related to Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), one of the most common types of chronic liver disease, is strongly correlated with obesity, insulin resistance, metabolic syndrome, and genetic components. The pathological progression of NAFLD, consisting of non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), and liver cirrhosis, is characterized by a broad spectrum of clinical phenotypes. Although patients with mild NAFL are considered to show no obvious clinical symptoms, patients with long-term NAFL may culminate in NASH and further liver fibrosis. Even though various drugs are able to improve NAFLD, there are no FDA-approved medications that directly treat NAFLD. In this paper, the pathogenesis of NAFLD, the potential therapeutic targets, and their underlying mechanisms of action were reviewed.

New Drugs for Hepatic Fibrosis

The morbidity and mortality of hepatic fibrosis caused by various etiologies are high worldwide, and the trend is increasing annually. At present, there is no effective method to cure hepatic fibrosis except liver transplantation, and its serious complications threaten the health of patients and cause serious medical burdens. Additionally, there is no specific drug for the treatment of hepatic fibrosis, and many drugs with anti-hepatic fibrosis effects are in the research and development stage. Recently, remarkable progress has been made in the research and development of anti-hepatic fibrosis drugs targeting different targets. We searched websites such as PubMed, ScienceDirect, and Home-ClinicalTrials.gov and found approximately 120 drugs with anti-fibrosis properties, some of which are in phase Ⅱ or Ⅲ clinical trials. Additionally, although these drugs are effective against hepatic fibrosis in animal models, most clinical trials have shown poor results, mainly because animal models do not capture the complexity of human hepatic fibrosis. Besides, the effect of natural products on hepatic fibrosis has not been widely recognized at home and abroad. Furthermore, drugs targeting a single anti-hepatic fibrosis target are prone to adverse reactions. Therefore, currently, the treatment of hepatic fibrosis requires a combination of drugs that target multiple targets. Ten new drugs with potential for development against hepatic fibrosis were selected and highlighted in this mini-review, which provides a reference for clinical drug use.

Metabolic Fatty Liver Disease in Children: A Growing Public Health Problem

Metabolic-associated fatty liver disease (MAFLD), previously called nonalcoholic fatty liver diseases (NAFLD), is one of the most important causes of chronic liver disease worldwide and will likely become the leading cause of end-stage liver disease in the decades ahead. MAFLD covers a continuum of liver diseases from fatty liver to nonalcoholic steatohepatitis (NASH), liver fibrosis/cirrhosis and hepatocellular cancer. Importantly, the growing incidence of overweight and obesity in childhood, 4% in 1975 to 18% in 2016, with persisting obesity complications into adulthood, is likely to be harmful by increasing the incidence of severe MAFLD at an earlier age. Currently, MAFLD is the leading form of chronic liver disease in children and adolescents, with a global prevalence of 3 to 10%, pointing out that early diagnosis is therefore crucial. In this review, we highlight the current knowledge concerning the epidemiology, risk factors and potential pathogenic mechanisms, as well as diagnostic and therapeutic approaches, of pediatric MAFLD.

Activation of AMPK by triptolide alleviates nonalcoholic fatty liver disease by improving hepatic lipid metabolism, inflammation and fibrosis

BACKGROUND

Triptolide is naturally isolated from Tripterygium wilfordii Hook F., possessing multiple biological activities. Hepatotoxicity is one of the main side effects of triptolide. However, the effect of triptolide on nonalcoholic fatty liver disease remains unknown (NAFLD).

PURPOSE

This study aimed to observe the amelioration of triptolide against NAFLD and investigate the engaged mechanism.

METHODS

Two typical animal models of NAFLD, obese db/db mice and methionine/choline-deficient (MCD) diet-fed mice, were used. Hepatic steatosis, inflammation, and fibrosis were evaluated by H&E and Masson staining. Oil red O staining and lipid extraction analysis were used to detect fat content in mice livers. Expression of lipid metabolism, inflammatory and fibrogenic genes was also detected by Real-time PCR and Western blotting, respectively. Phosphoproteomics, molecular docking, and TR-FRET assay were performed to provide further insight into how triptolide improved NAFLD.

RESULTS

Intraperitoneal injection of triptolide at a daily dose of 50 μg/kg significantly alleviated MCD diet-induced nonalcoholic steatohepatitis (NASH), but 100 μg/kg triptolide caused severe hepatotoxicity. Pathological staining confirmed low-dose triptolide treatment reducing hepatic lipid deposition, inflammation, and fibrosis in NASH. Serum biochemical analysis revealed a reduction in the level of liver enzymes and bilirubin. MCD also induced rising expression of typical genes and proteins related to fibrosis (fibronectin, α-SMA, collagens, TGF-β) and inflammation (ILs, TNF-α, MCP-1), which was suppressed by low-dose triptolide. Data from the proteomics/phosphoproteomics and TR-FRET assay indicated triptolide was a potential allosteric AMPK agonist to increase the phosphorylation on Thr172 residue, with the EC₅₀ of 277.78 μM and 231.02 μM for AMPKα1 and AMPKα2, respectively. Moreover, triptolide exhibited an ability to activate AMPK and further led to increasing ACC1 phosphorylation in the liver. The positive results that triptolide ameliorated hepatic lipogenesis, fatty acid oxidation, and fibrosis of NAFLD via activating AMPK were further confirmed in db/db mice with 10-week intervention (50 μg/kg, i.v., twice a week).

CONCLUSION

This study demonstrates that dose-related triptolide as an allosteric AMPK agonist has the potential to alleviate NAFLD without hepatotoxicity.

Target Therapies for NASH/NAFLD: From the Molecular Aspect to the Pharmacological and Surgical Alternatives

Non-alcoholic fatty liver disease represents an increasing cause of chronic hepatic disease in recent years. This condition usually arises in patients with multiple comorbidities, the so-called metabolic syndrome. The therapeutic options are multiple, ranging from lifestyle modifications, pharmacological options, to liver transplantation in selected cases. The choice of the most beneficial one and their interactions can be challenging. It is mandatory to stratify the patients according to the severity of their disease to tailor the available treatments. In our contribution, we review the most recent pharmacological target therapies, the role of bariatric surgery, and the impact of liver transplantation on the NAFLD outcome.

Therapeutic effects of myocardin-related transcription factor A (MRTF-A) knockout on experimental mice with nonalcoholic steatohepatitis induced by high-fat diet

OBJECTIVE

To explore the effects of myocardin-related transcription factor A (MRTF-A) knockout on mice with nonalcoholic steatohepatitis (NASH) induced by high-fat diet (HFD).

METHODS

Normal-fat diet (NFD) or HFD was fed to MRTF-A-knockout (MRTF-A^-/-) and wild-type (WT) mice for 16 weeks. Liver histopathological status was observed using Hematoxylin and Eosin (HE) staining, Oil Red O staining, Sirius Red staining, and Immunohistochemical staining. The mRNA and protein levels in liver tissues were measured through quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot.

RESULTS

Compared with WT + HFD group, mice in MRTF-A^-/- + HFD group were decreased in body weight, blood glucose, plasma insulin, liver TG and NAFLD activity score (NAS), with liver function recovery. Besides, compared with HFD-fed WT mice, HFD-fed MRTF-A^-/- mice were improved in hepatic fibrosis, accompanied by decreased collagen content (%) and down-regulated expressions of α-SMA, COL1A2, TGFβ1, and SMAD3. In mice fed with HFD, the expression of MCP-1, CCR2, F4/80 and CD68 declined in liver tissues of MRTF-A^-/- mice as compared with WT mice. Besides, in hepatic macrophages isolated from HFD-fed mice, the observed increased expression of TNF-α, IL-1β, MCP-1, as well as decreased expression of CCR2. Compared with WT + HFD group, MRTF-A^-/- + HFD group mice were decreased regarding NF-κB p65 in liver tissues.

CONCLUSION

MRTF-A knockout reduced macrophage infiltration, down-regulated NF-κB p65 expression, and ameliorated inflammation and fibrosis of liver tissues in mice, thereby becoming a potential therapeutic target for NASH treatment.

[Chronic kidney injury in patients with liver diseases - Reappraising pathophysiology and treatment options]

Acute and chronic kidney disease concurs commonly with liver disease and is associated with a wide array of complications including dialysis dependency and increased mortality. Patients with liver disease or liver cirrhosis show a higher prevalence of chronic kidney disease. This is attributed to concomitant comorbidities, such as metabolic syndrome, chronic inflammation, hypercoagulability, hyperfibrinolysis, diabetes mellitus and dyslipidaemias. But chronic progressive kidney disease is not always due to hepatorenal syndrome. Beyond that, other diseases or disease entities should be considered. Among them are diabetic nephropathy, secondary IgA nephropathy, hepatitis C -associated membranoproliferative Glomerulonephritis (MPGN) and hepatitis B-associated membranous nephropathy.Coexisting diseases, similar underlying pathophysiologic mechanisms, or simultaneously concurring pathophysiological processes and overlapping clinical manifestations, impede the etiologic diagnosis and corresponding treatment of chronic kidney disease in the setting of chronic liver disease. In this review, we focus on common and rare pathologies, which can lead to chronic kidney disease in this particular patient group and try to summarize the most recent therapeutic modalities.