30-LB: Study on the Mechanism of Calycosin in Promoting Wound Healing in Diabetic Foot Ulcers

Objective: To investigate the effect of calycosin in promoting wound healing of foot ulcers and explore the regulation on vascular endothelial growth factor (VEGF). Methods: 8-week-old male C57BL/6J mice were injected intraperitoneally with 1% streptozotocin 120 mg/kg for 3 consecutive times, and the mice with random blood glucose > 16.7 mmol/L were used and randomly divided into model group and calycosin suspension groups (30 mg/kg, 60 mg/kg, 90 mg/kg). Mice were pretreated for 30 days at a dose of 10 mL/kg of the corresponding drugs once a day, and the control group was given the same dose of 0.5% sodium carboxymethyl cellulose solution. At the end of administration, the animals were anesthetized with isoflurane and the whole layer of skin with diameter 10 mm was removed on the back to establish the wound model of diabetic foot ulcer as day 0. The wound healing was observed and photographed with a camera on the day 0, 2, 4, 6, 8, 10 and 12, respectively. At the end of the day 12, the new tissues around the wound were taken for the detections of the growth of new granulation tissue, VEGF, CD31 and the content of sorbitol. Results: Compared with the model group, the wound healed faster in calycosin groups. It closed on the 12th day, but the wound in the model group did not heal completely. However, there was no obvious dose-effect relationship between different dose groups. The mice in treatment groups showed a better structural integrity of epidermis, and a more expression of VEGF and CD31 in the newborn tissue. And the protein level of VEGF of the calycosin (60 mg/kg) group increased. And the sorbitol content in calycosin (90 mg/kg) group reduced significantly (P<0.05), while in 30 mg/kg and 60 mg/kg changed slightly. Conclusion: Calycosin could promote the wound healing of diabetic foot ulcer, which may be related to the effect of increasing the level of VEGF and reducing the accumulation of sorbitol in tissues. And further research was needed for fully exploration on the mechanism. Disclosure Y. Xu: None. J. Ke: None. L. Yang: None. D. Zhao: None. Funding Tongzhou District Science and Technology Plan Project (KJ2022CX024)