Liver enhancer signature and regulatory network of non-alcoholic steatohepatitis resistance in humans with obesity

The molecular underpinnings of non-alcoholic steatohepatitis (NASH) development in patients are poorly understood. Active enhancer landscapes are known to determine cell states and behaviors. Super-enhancers, in particular, have helped reveal key disease drivers in several cancer types; however, they remain unexplored in human NASH. To define the enhancer signature of NASH-prone (NP) and NASH-resistant (NR) phenotypes in humans with obesity, we performed chromatin run-on sequencing (ChRO-seq) analysis on liver biopsies of individuals with obesity who were stratified into either NP or NR. We first demonstrated that NP and NR groups exhibit distinct active enhancer signatures. The subsequent identification of NP- and NR-specific super-enhancers revealed the specific genes that are likely the most critical for each of the phenotypes, including HES1 for NP and GATM for NR. Integrative analysis with results from genome-wide association studies of NAFLD and related traits identified disease/trait-loci specific to NP or NR enhancers. Further analysis of the ChRO-seq data pointed to critical roles for serine/glycine metabolism in NASH resistance, which was corroborate by profiling of circulating amino acids in the same patients. Overall, the distinct enhancer signatures of human NP and NR phenotypes revealed key genes, pathways, and transcription factor networks that promote NASH development.