Preface

Non-alcoholic fatty liver disease (NAFLD) is the leading primary cause of chronic liver disease in both children and adults worldwide. Global prevalence is estimated at 25% and accounts for the most common etiology of abnormal liver function tests in Western countries. NAFLD is a clinical-histopathologic entity with histologic features that resemble alcohol-induced liver injury, but by definition it occurs in patients with little or no history of alcohol consumption. It encompasses a histologic spectrum that ranges from fat accumulation in hepatocytes without concomitant inflammation or fibrosis (simple hepatic steatosis) to hepatic steatosis with a necroinflammatory component (steatohepatitis) that may or may not have associated fibrosis. The latter condition, referred to as nonalcoholic steatohepatitis (NASH), may progress to cirrhosis in up to 20% of patients. NASH is now recognized to be a leading cause of cryptogenic cirrhosis.

The pathogenesis of NAFLD has not been fully elucidated. The most widely supported theory implicates insulin resistance as the key mechanism leading to hepatic steatosis, and perhaps also to steatohepatitis. Others have proposed that a "second hit," or additional oxidative injury, is required to manifest the necroinflammatory component of steatohepatitis. Hepatic iron, gut hormones, antioxidant deficiencies, and intestinal bacteria have all been implicated in the pathogenesis of NAFLD.

This book includes contributions from global experts that present and discusses the most current results and theory for the pathogenesis of NAFLD. In addition to the knowledge shared, the authors provide their personal experimental experience, making this book an extremely useful tool for researchers in this field. Chapters discuss hepatic iron metabolism, the role of heparanase, ERR regulation, lipid homeostasis, therapeutic approaches, and HDL as a molecular modifier in the pathogenesis of NAFLD.

> **Ju-Seop Kang MD, Ph.D.** Professor of Pharmacology and Clinical Pharmacology, College of Medicine, Hanyang University, Seoul, South Korea

**1**

Section 1

Basic Concept and Molecular

Aspect in the Development

of NAFLD/NASH

Section 1
