Fig. 1
Establishment of the HFD/STZ-induced long-term T2DM rat model. a Illustration for the study design. To produce the long-term T2DM complication rodent model, 8-week-old male SD rats were fed a HFD for 8 weeks, followed by an STZ injection at a single dose of 25 mg/kg. HFD feeding and hyperglycaemia were maintained in the newly diabetic rats for 24 weeks. Then, the long-term T2DM complication rats were randomly treated with one of the following interventions: infusions of 3 × 106 ADSCs suspended in 0.5 ml of PBS through the tail vein once a week for 24 weeks (referred to as the MSC-treated group, N = 6) or infusions of 0.5 ml PBS alone once a week for 24 weeks (referred to as the T2DM group, N = 6). Normal rats of the same age that fed NCD were used as the control (referred to as the control group, N = 6). On week 57 (after 24 times of ADSC treatment), the therapeutic effects of ADSCs on T2DM complications were assessed. b Body weight, FBG, FBI, serum C-peptide, HOMA-IR, HOMA-β, and ACR at the time point before HFD (HFD-b), before STZ injection (STZ-b), 1 week after STZ injection (STZ-1w), 12 weeks after STZ injection (STZ-12w), and 24 weeks after STZ injection (STZ-24w). c Representative sections of epididymal adipose, pancreas, and kidney staining with H&E; bars = 50, 50, and 20 μm. N = 6 rats per group; *p < 0.05, **p < 0.01