Since systemic administration of FGF21 has been proved to significantly reduce plasma glucose and triglyceride in animal models of type 2 diabetes in previous studies [5], we measured the plasma glucose levels for all animals by tail blood at 1 h after the injection of rhFGF21 on day 3 (Figure 6A) and 7 (Figure 6B) during the treatment. Here, FGF21 is linked to type 2 diabetes mellitus.