Insulin resistance results in accumulation of
triglyceride content and reduction of
glycogen content in skeletal muscle. However, very few studies have measured
lipid content and
glycogen content in liver associated with
insulin resistance. We studied the relationship between liver
lipid content,
liver glycogen, and
insulin resistance in high-fat-fed rats, which are animal models of
insulin resistance. High-fat-fed rats were hyperlipidemic, hyperglycemic, and hyperinsulinemic. Furthermore, the
glucose infusion rates (GIR) were lower (normal rats, 10.35 +/- 1.66; high-fat-fed rats, 4.86 +/- 0.93 mg/kg/min; P <.01) and the
triglyceride and
cholesterol contents in liver were higher in the high-fat-fed rats than in normal rats. On the other hand, the
glycogen content in liver was lower than in normal rats. There was an inverse relationship between liver
triglyceride content and
liver glycogen content. When the
lipoprotein lipase (LPL) activator
NO-1886 was administered to the high-fat-fed rats at a daily dose of 50 mg/kg
body weight for 10 weeks, GIR (9.87 +/- 3.76 mg/kg/min, P <.05 v high-fat-fed control group) improved, causing an improvement of the
hyperlipidemia,
hyperglycemia, and
hyperinsulinemia. Furthermore,
NO-1886 decreased
triglyceride and
cholesterol concentrations and increased
glycogen content in liver of the high-fat-fed rats. In this study, we found that
insulin resistance caused
fatty liver and reduced
glycogen content in liver. Administration of the LPL activator
NO-1886 improved the
insulin resistance, resulting in an improvement in the relationship between
triglyceride and
glycogen content in liver of high-fat-fed rats.