Figure 1.

A: Insulin secreted from the pancreas suppresses fat lipolysis, hepatic triglyceride (TG) secretion, and gluconeogenesis. Insulin also acts on the brain, which independently suppresses lipolysis by suppression of sympathetic outflow and increases TG secretion from the liver through an unknown mechanism. B: In diabetes, decreased insulin action on the brain and fat results in increased lipolysis. This increases the delivery of free fatty acids (FFAs) to the liver, increasing TG synthesis. Impaired insulin action at the liver results in increased gluconeogenesis. Increased blood glucose and decreased insulin action at the brain suppress TG secretion from the liver.