Sitagliptin therapy significantly reduced fasting plasma triglyceride ( -@ % , p = @ ) , apoB-@ ( -@ % , p = @ ) and free fatty acid concentrations ( -@ % , p = @ ) , as well as plasma HbA@c ( placebo : @ % @ vs. sitagliptin : @ % @ , p < @ ) and plasma glucose levels ( -@ % , p = @ ) , without any significant effect on insulin levels .