Insulin resistance is the pathophysiological hallmark of various kinds of clinical diseases, including non- alcoholic fatty liver disease. Insulin resistance is the common characteristic of metabolic syndrome and its related features. Insulin resistance is a systemic disease that affects the nervous system, muscles, pancreas, kidney, heart and immune system, in addition to the liver. A complex interaction between genes and environment factors enhances insulin resistance and the phenotypic expression of NAFLD (non- alcoholic fatty liver disease) in individual patients. Advanced fibrotic liver disease is associated with many features of metabolic syndrome, and the risk of progressive liver disease should not be underestimated for the individuals suffering with metabolic disorders. Abnormalities of insulin signaling can cause the state of insulin resistance, but there is no clear cut scientific evidence that distorted insulin signaling is the primary pathophysiological defect. Increased adipose tissue mass can cause peripheral tissue insulin resistance via the changes of the adipocytokine secretory patterns. We discuss in this article the sequences of the insulin signaling cascades and the possible molecular targets of insulin resistance, the humoral “cross talk” between the distorted secretory patterns of the adipocytokines, and the peripheral tissue insulin resistance along with the pathophysiology of NAFLD. (Korean J Hepatol 2006;12:16-30)
