Targeting Extracellular RNA Mitigates Hepatic Lipotoxicity and Liver Injury in NASH.

Area of Science:

• Hepatology
• Molecular Biology
• Immunology

Background:

• Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD).
• Current diagnostic tools and treatments for NASH are limited.
• NASH involves hepatocyte damage, inflammation, and fibrosis, driven by molecular mechanisms like lipid toxicity.

Purpose of the Study:

• To investigate the role of extracellular RNAs (eRNAs) as damage-associated molecular patterns (DAMPs) in NASH pathogenesis.
• To evaluate the therapeutic potential of inhibiting eRNA activity in NASH.

Main Methods:

• Assessed the impact of lipotoxicity-induced hepatocyte damage on eRNA release in HepG2 cells.
• Investigated the pro-inflammatory and pro-apoptotic effects of eRNAs.
• Administered RNase 1 to inhibit eRNA activity in vitro and in a murine NASH model.
• Measured cellular viability, cytokine production, and NASH-related markers.

Main Results:

• Hepatocyte damage releases eRNAs that act as DAMPs, promoting apoptosis and inflammation.
• Inhibition of eRNA activity by RNase 1 enhanced HepG2 cell viability and reduced NF-kB-mediated cytokine production.
• RNase 1 treatment improved hepatic steatosis, inflammation, and injury markers in a mouse model of NASH.

Conclusions:

• Extracellular RNAs play a significant role in NASH progression by mediating lipotoxicity-induced liver injury.
• Inhibiting eRNA activity represents a novel therapeutic strategy for NASH.
• RNase 1 demonstrates potential efficacy in ameliorating NASH phenotypes.