Pharmacological activation of REV-ERBα improves nonalcoholic steatohepatitis by regulating intestinal permeability

Background and objectives: The gut-liver axis plays an important role in the pathogenesis of nonalcoholic steatohepatitis (NASH), and increased intestinal permeability causes transfer of endotoxin to the liver, which activates the immune response, ultimately leading to hepatic inflammation. Nuclear receptor Rev-erb alpha is a critical regulator of circadian rhythm, cellular metabolism, and inflammatory responses. However, the role and mechanism of Rev-erb alpha in gut barrier function and NASH remain unclear. In the present study, we investigated the involvement of Rev-erb alpha in the regulation of intestinal permeability and the treatment of NASH. Methods and results: The expression of tight junction-related genes and Rev-erbs decreased in the jejunum, ileum and colon of mice with high cholesterol, high fat diet (CL)-induced NASH. Chromatin immunoprecipitation analysis indicated that REV-ERB alpha directly bound to the promoters of tight junction genes to regulate intestinal permeability. Pharmacological activation of REV-ERB alpha by SR9009 protected against lipopolysaccharide-induced increased intestinal permeability both in vitro and in vivo, and these effects were associated with the activation of autophagy and decreased apoptotic signaling of epithelial cells. In addition, the chronopharmacological effects of SR9009 were more potent at Zeitgeber time 0 (ZT0) than at ZT12, which was contrary to the rhythm of Rev-erbs in the gastrointestinal tract. The administration of SR9009 attenuated hepatic lipid accumulation, insulin resistance, inflammation, and fibrosis in mice with CL diet-induced NASH, which might be partly attributed to the enhancement of intestinal barrier function. Conclusion: Chronopharmacological activation of REV-ERB alpha might be a potential strategy to treat intestinal barrier dysfunction-related disorders and NASH. (C) 2020 Elsevier Inc. All rights reserved.

Automated summary

The study found that Rev-erb alpha decreased in the intestines of mice with high cholesterol, high fat diet-induced NASH, and by activating autophagy and reducing apoptotic signaling of epithelial cells, it protected against increased intestinal permeability. This led to improvements in hepatic lipid accumulation, insulin resistance, inflammation, and fibrosis in mice with NASH.