Diabetic Foot Ulcer Mouse Model

We established the mice model of DFU according to the previous study of Li [22 (link)]. In general, male BALB/c mice (Shanghai Laboratory Animal Center of Chinese Academy of Sciences, China) with 5 weeks age and 19.39 ± 1.56 g weight were treated with 0.45% streptozotocin (Sigma, USA, 45 mg/kg) and feed with high-fat diet. We choosed these mice with the blood glucose level at 16.7 mmol/L to establish DFU model. There were 62 mice with DM. Then, we used the sterile punch to make wounds. Finally, exosomes derived from mmu_circ_0001052-modified ADSCs (exosomes + mmu_circ_0001052 group) or exosomes from vector-modified ADSCs (exosome + vector group) were subcutaneously injected. 25 μL of exosomes (200 μg in 100 μL PBS) were subcutaneously injected at 4 sites around the wound. The control group was not treated with exosomes. Wound tissues were collected at 3, 7 and 14 days after wounding. This study, following the Nation Institutes of Health Guide for the Laboratory Animals Care and Use, was carried out with the approval of hospital ethics committee, and Ethical approval No.:Med-Eth-Re [2021] 192.