Study on establishment of congenic strains and screening of characteristics in IRS-2 deficient mice to support translational research on type 2 diabetes.

In research into type 2 diabetes, diet-based approaches, i.e., nutritional intake, are important approaches for therapeutic research. We would like to make the following two proposals from the standpoint of laboratory animal science for reproducible animal studies using type 2 diabetes mouse models. These include congenic strains of diabetes mouse models and improvement of diets used in daily care and management. In this research, the Irs2homo-knockout mouse with both impaired glucose tolerance and insulin resistance, and thus type 2 diabetes, was established as a congenic strain. The effect of the genetic background on the onset of diabetes was examined. Next, we discussed which diets are appropriate for general care and management of mouse models in which the pathophysiology is controlled by nutritional conditions. Therefore, we prepared diets by converting the current Japanese and US diets to mice and adjusting the diet contents accordingly. We compared the insulin signals such as those of the liver, pancreas and white fat. We were thus able to establish an evaluation system closer to diabetes in the current population. Using this data as an example, we should consider the quality and ordinary diet of animals as important factors in animal experiments.