The Assessment of Glucose Homeostasis in Rodents: Glucose, Insulin and Pyruvate Tolerance Tests

Medical management of obese and type II diabetes patients has improved greatly in the last century. However, even with technological advances, the underlying cause of glucose intolerance and insulin resistance remains unclear, limiting the development of efficient pharmacotherapies. In this sense, preclinical studies are highly valuable and necessary. However, the huge number of available animal models, experimental procedures, and variability in performing or analyzing metabolic tests can easily lead to misunderstanding and misinterpretation. Reliability and reproducibility of experimental procedures are of critical importance for any pre- or clinical study, independently of the investigation field. Thus, in order to ensure harmonization, we provide detailed protocols to perform glucose (GTT), insulin (ITT), and pyruvate (PTT) tolerance tests. Additionally, other important considerations mainly related to species and strain, age, sex, housing/handling, environment, stress, and recovery are discussed to obtain reliable and relevant results that could help to unravel the complexity of metabolic pharmacotherapies.