Modified streptozotocin-induced diabetic model in rodents

Streptozotocin (STZ)-induced type I diabetes mellitus (DM) models have been pivotal in diabetes research due to their ability to mimic the insulin-dependent hyperglycemia akin to human type I diabetes. However, these models often suffer from poor induction rates and low survival post-STZ induction, especially in long-term experiments, necessitating insulin supplementation, which introduces additional variables to experiments. To address this, we present a novel modification to the STZ-induced DM model in C57BL/6J mice to improve survival rates without insulin supplementation. Our method involves non-fasting, low-dose STZ injections dissolved in pH-neutral phosphate buffer saline instead of acidic sodium citrate buffer, administered over 5 days. We observed hyperglycemia induction in 94.28% of mice within a week post-injection, with stable high blood glucose levels, stable body weight, and minimal mortality up to 21 weeks. Notably, omitting 10% sucrose in water and fasting did not affect hyperglycemia induction. Our findings suggest that the modified protocol not only decreases the experimental effort of the researchers, but reduces animal stress and mortality, thus enhancing experimental outcomes and animal welfare. By optimizing the STZ-induced DM model in C57BL/6J mice, our study provides a valuable resource for researchers aiming to study diabetes and its complications while minimizing experimental variability and animal usage.