Selective disruption of NRF2-KEAP1 interaction leads to NASH resolution and reduction of liver fibrosis in mice

Background & Aims

Oxidative stress is recognized as a major driver of non-alcoholic steatohepatitis (NASH) progression. The transcription factor NRF2 and its negative regulator KEAP1 are master regulators of redox, metabolic and protein homeostasis, as well as detoxification, and thus appear to be attractive targets for the treatment of NASH.

Methods

Molecular modeling and X-ray crystallography were used to design S217879 - a small molecule that could disrupt the KEAP1-NRF2 interaction. S217879 was highly characterized using various molecular and cellular assays. It was then evaluated in two different NASH-relevant preclinical models, namely the methionine and choline-deficient diet (MCDD) and diet-induced obesity NASH (DIO NASH) models.

Results

Molecular and cell-based assays confirmed that S217879 is a highly potent and selective NRF2 activator with marked anti-inflammatory properties, as shown in primary human peripheral blood mononuclear cells. In MCDD mice, S217879 treatment for 2 weeks led to a dose-dependent reduction in NAFLD activity score while significantly increasing liver Nqo1 mRNA levels, a specific NRF2 target engagement biomarker. In DIO NASH mice, S217879 treatment resulted in a significant improvement of established liver injury, with a clear reduction in both NAS and liver fibrosis. αSMA and Col1A1 staining, as well as quantification of liver hydroxyproline levels, confirmed the reduction in liver fibrosis in response to S217879. RNA-sequencing analyses revealed major alterations in the liver transcriptome in response to S217879, with activation of NRF2-dependent gene transcription and marked inhibition of key signaling pathways that drive disease progression.

Conclusions

These results highlight the potential of selective disruption of the NRF2-KEAP1 interaction for the treatment of NASH and liver fibrosis.

Impact and implications

We report the discovery of S217879 - a potent and selective NRF2 activator with good pharmacokinetic properties. By disrupting the KEAP1-NRF2 interaction, S217879 triggers the upregulation of the antioxidant response and the coordinated regulation of a wide spectrum of genes involved in NASH disease progression, leading ultimately to the reduction of both NASH and liver fibrosis progression in mice.

Safety and therapeutic effects of anti-fibrotic Traditional Chinese Medicine Fuzheng Huayu on persistent advanced stage fibrosis following 2 years entecavir treatment: Study protocol for a single arm clinical objective performance criteria trial

BACKGROUND

Hepatitis B virus (HBV) infection is an important etiology for chronic hepatitis globally, and especially so in China. HBV infection can lead to the development of cirrhosis through the pathological process of liver fibrosis. The effective suppression of HBV replication with NAs or interferon-alpha can histologically regress the fibrotic pathological process, but there remain patients who have achieved anti-viral responses and normalization of serum liver tests, but not liver fibrosis regression. This subset of patients typically presents with advanced liver fibrosis at baseline. Therefore, it is reasonable to administer the anti-fibrotic agents, coupled with antivirals for patients with advanced liver fibrosis due to HBV, in order to improve the fibrotic regression of the patients. Fuzheng Huayu (FZHY) tablet is a botanical product with evidence demonstrating its efficacy against mild to moderate liver fibrosis. The current clinical trial evaluates the efficacy and safety of the combination therapy of traditional Chinese medicine (TCM) (FZHY and herbal granule) and entecavir for HBV compensated cirrhosis. We will enroll HBV patients who presented with a good viral response after 2 years of entecavir treatment but had advanced liver fibrosis (≥Ishak F5).

METHODS

This is a single-arm clinical trial, conducted in 20 centers in mainland China over a period of 60 weeks, including 48 weeks of treatment observation and 12 weeks of follow-up. The main inclusion criteria include HBsAg positive more than 6 months, 2 years administration of entecavir, HBV DNA less than 20 IU/ml, liver fibrotic stage ≥ F5, and Child-Pugh scoring <7 (Stage A). The sample size is estimated to be about 190, considering a 20% drop-out and 60% of patient's compliance for the second liver biopsy so a total of 350 participants will be enrolled. All eligible participants are divided into 3 subgroups according to the TCM clinic pattern. And all patients will take 1 Entecavir tablet (0.5 mg) per day, 4 FZHY tablets (1.6 g) three times a day, and specific TCM granule three times a day, which is decided by TCM clinical patterns (CPs) differentiation. The patients were treated for 48 weeks, and follow-up visits at 12, 24, 36, 48 weeks and 60 weeks. The patients will receive the second liver biopsy at the end of 48 weeks, with a 12 weeks follow-up after that.The primary endpoint is the proportion of subjects with a 1-point improvement of liver fibrosis stage using the Ishak score from baseline to week 48 in the study, according to consensus readings evaluated by a panel of hepato-pathologists. The secondary endpoints are the brightness-mode ultrasonic, fibrotic biomarkers. The adverse events (AEs) will be recorded for 60 weeks, and the safety of the combination therapy will be evaluated. Meanwhile, the efficacy in the 3 sub-groups will be stratified and analyzed.

DISCUSSION

The study has been designed to test the therapeutic effects and safety of the combination therapy of FZHY and herbal granule with entecavir on persistent advanced stage fibrosis/cirrhosis following 2 years entecavir treatment, and to explore an effective integrative therapy on HBV cirrhosis.

TRIAL REGISTRATION

ClinicalTrials.gov. NCT02241616. Registered on September 16, 2014.

Evaluation of Plasma Urokinase-Type Plasminogen Activator Receptor (UPAR) in Patients With Chronic Hepatitis B, C and Non-Alcoholic Fatty Liver Disease (NAFLD) as Serological Fibrosis Marker

BACKGROUND/AIMS

Progressive hepatic fibrosis is the main predictor of outcome and prognosis in chronic liver diseases. The importance of the coagulation cascade has been defined in liver fibrosis; however, the role of the fibrinolytic pathway has not been clear yet. We aimed to evaluate the association between the plasma levels of soluble urokinase Plasminogen Activator Receptor (uPAR) and the severity of liver fibrosis in chronic hepatitis B, C and Non-Alcoholic Fatty Liver Disease (NAFLD).

METHODS

96 chronic hepatitis B, 22 chronic hepatitis C and 11 NAFLD patients together with 47 healthy controls were enrolled in the study. uPAR plasma levels were detected by Enzyme-Linked Immunosorbent Assay (ELISA) method.

RESULTS

The plasma levels of uPAR in patients with chronic hepatitis B and C significantly exceeded those of healthy controls (P < 0.001) while mean uPAR levels in patients with NAFLD were not different from healthy controls. Mean uPAR levels in chronic viral hepatitis patients with F1-F3 fibrosis and F4-F6 fibrosis were higher than those of control group (P < 0.001). Mean uPAR level in patients with F4-F6 fibrosis was significantly higher than that of patients with F1-F3 fibrosis (P < 0.001).

CONCLUSION

This is the first study that investigated uPAR as a fibrosis marker in NAFLD and chronic hepatitis B patients. It is suggested that plasma levels of uPAR are closely related to the fibrosis stage in chronic hepatitis B and C and that uPAR might be a noninvasive marker of liver fibrosis.