Proliferation of activated hepatic stellate cells requires REST

Abstract Background Activation of hepatic stellate cells (HSCs) is key in liver regeneration and the pathogenesis of chronic liver diseases, such as metabolic dysfunction-associated steatohepatitis (MASH). Activated HSCs promote liver inflammation and fibrosis which can lead to the development of liver cancer. Targeted removal of activated HSCs has shown promise in preventing liver fibrosis and liver cancer in mouse models. HSC activation is characterized by increased mitochondrial metabolism and upregulation of pro-fibrotic genes, but the underlying regulatory mechanisms remain incompletely understood. Since RE1-silencing transcription factor (REST) is known to regulate cell fate and metabolism, we investigated its involvement in HSC activation. Methods REST-dependent mechanisms of HSC activation were studied using siRNA-mediated REST knock down in primary human HSCs and human HSC-like LX2 cells. Results Knock down of REST in primary human HSCs and HSC-like LX2 cells reduced proliferation, promoted lipid accumulation and autophagy, and impaired mitochondrial metabolism, resulting in reduced growth. The effects were linked with REST-dependent regulation of the PI3K/AKT/mTORC1 pathway. Conclusions Our findings identify a REST-dependent mechanism of HSC activation that is important for their activation and proliferation.