Accu chek active blood glucose meter

All participants were required to fast overnight by stopping food intake from 8 p.m. on the day prior to sample collection. Five milliliters of venous blood was taken from each participant by a trained phlebotomist after the overnight fast and a drop of whole blood was placed on the Accu-Chek® Active blood glucose strip and read with Accu-Chek® Active blood glucose meter (Roche Diabetes Care, Inc., USA) to determine the fasting blood sugar. The remaining blood sample was put into an EDTA sample bottle and was spun at 2500 rpm to obtain plasma for other biochemical assays.

C57BL/6N mice (JSJ Lab, Shanghai, China) were acquired and used to generate type 1 DM disease model in both the male and female mice. The exact number of animals for individual experiments is reported in figure legends. Type 1 DM disease model was established using intraperitoneal injection of STZ (150 mg/kg body weight, V900890, Sigma-Aldrich, USA) after a 10-h fast in 8 weeks old C57BL6/N mice. In parallel, equal volume of 0.1 M sodium citrate was injected and served as control. Blood glucose measurements were monitored using an Accu-Chek Active Blood Glucose Meter (Roche Diabetes Care GmbH, Mannheim, Germany) once every 2 weeks post-STZ induction. Three consecutive random blood glucose measurements > 16.7 mM deemed modeling success and were used as type 1 DM model (DM group) in subsequent analyses. STZ mice post-10 weeks of initial injection exhibiting stable diastolic dysfunction (defined as the DCM group) were subjected to hypoglycemic challenge. Insulin (100 IU, Yuanye Biotechnology Corporation Ltd., Shanghai, China) was injected intraperitoneally to induce hypoglycemia (HDCM group), <3.0 mmol/l glucose postinsulin induction, and animals were sacrificed 120 min postinjection (Figure 2A).