Progressive Liver Fibrosis in Non-Alcoholic Fatty Liver Disease

Area of Science:

• Hepatology
• Gastroenterology
• Oncology

Background:

• Non-alcoholic steatohepatitis (NASH) is a chronic, progressive liver disease with increasing global incidence.
• NASH significantly contributes to morbidity, mortality, reduced quality of life, and increased liver transplant needs.
• Patients with NASH face an elevated risk of hepatocellular carcinoma due to chronic liver injury.

Purpose of the Study:

• To review the evolving understanding of NASH pathogenesis.
• To contrast the traditional "two-hit" model with the current "multi-hit" paradigm.
• To highlight the multifactorial pathways implicated in NASH progression and oncogenesis.

Main Methods:

• Literature review of current scientific evidence on NASH.
• Analysis of proposed pathogenetic models for NASH.
• Synthesis of data on cellular, genetic, immunological, metabolic, and endocrine factors.

Main Results:

• The "two-hit" model (steatosis followed by inflammation/lipid peroxidation) is insufficient to explain NASH progression.
• A "multi-hit" or "multi-parallel hit" model is now favored.
• This complex model incorporates diverse pathways contributing to fibrosis and hepatocellular carcinoma.

Conclusions:

• NASH pathogenesis is more intricate than previously understood.
• Multiple parallel pathways are involved in the progression of liver damage and cancer development in NASH.
• Understanding these complex mechanisms is crucial for developing effective therapeutic strategies.