RNA expression changes driven by altered epigenetics status related to NASH etiology.

Area of Science:

• Epigenetics
• Molecular Biology
• Hepatology

Background:

• Non-alcoholic fatty liver disease (NAFLD) is a growing global health concern, often progressing to non-alcoholic steatohepatitis (NASH).
• NASH is characterized by liver inflammation, hepatocellular ballooning, and fibrosis, potentially leading to liver failure or cancer.
• Metabolic factors, diet, and lifestyle influence NAFLD/NASH by affecting cellular epigenetic landscapes and gene expression.

Purpose of the Study:

• To investigate chromatin accessibility and gene expression changes in liver biopsies from NASH patients.
• To identify epigenetic alterations and their correlation with transcriptional changes in NASH etiology.

Main Methods:

• ATAC-sequencing and RNA-sequencing were employed on liver biopsies.
• Chromatin accessibility data was integrated with known liver enhancer regions.

Main Results:

• NASH patients exhibited transcriptional downregulation in lipid and glucose metabolic pathways.
• 229 differentially enriched genes (ATAC and mRNA) were identified in NASH, linked to lipid transport and PPARA regulation.
• Differential chromatin openness was observed at 8 enhancers, including those near lipid metabolism (FASN) and glucose homeostasis (GCGR) genes.

Conclusions:

• The chromatin landscape is significantly altered in NASH patients.
• These epigenetic alterations correlate with mRNA expression changes, offering insights into NASH pathophysiology.
• Understanding these epigenetic modifications may reveal novel therapeutic targets for NASH.