OBJECTIVE To explore the effect and mechanism of Huiyang Shengji Decoction on wound healing in mice with diabetic yin syndrome.

METHODS SPF C57BL/6 mice were selected, and 24 diabetic ulcer models were established by intraperitoneal injection of streptozotocin and skin defect method. The mice were randomly divided into model group, low-dose, medium-dose and high-dose Huiyang Shengji Decoction groups, with 6 mice in each group. Six mice were selected to establish a common wound model as the blank group. The blank group and model group were treated with distilled water by intragastric administration every day, and the Huiyang Shengji Decoction groups were treated with Huiyang Shengji Decoction by intragastric administration every day. The wounds were photographed every day, and the wound healing rate was recorded. HE staining was used to observe the growth of granulation tissue in the wounds. Western blot was used to detect the expression of Axl, Tyro3 and Mertk proteins related to wound efferocytosis. Immunohistochemistry was used to detect the expression of CD11c in wound tissue. qPCR was used to detect the mRNA expression of TNF-α, IL-1β, IL-10 and TGF-β1 in the wounds. TUNEL staining was used to calculate the number of apoptotic cells (AC) in the wounds. Mouse primary bone marrow dendritic cells (BMDC) were resuspended in 1640 medium containing 10% blank serum or 5%, 10%, and 20% Huiyang Shengji Decoction-containing serum. After culturing in a cell culture incubator at 37 ℃ and 5% CO₂ for 24 h, the wound endocytosis-related receptors were detected by Western blot. BMDC and AC were co-cultured in vitro, and the phagocytic rate of BMDC phagocytosis of AC was detected by flow cytometry.

RESULTS The wound healing in each dose group of Huiyang Shengji Decoction was significantly faster than that in the model group (P < 0.05). Compared with the model group, the protein expression of Axl and Tyro3 in the wound tissue of mice in the high dose group of Huiyang Shengji Decoction was significantly increased (P < 0.01, P < 0.000 1), and there was no significant difference in the expression of Mertk protein in the wound tissue of mice in the low, medium and high dose groups (P0.05). The Huiyang Shengji Decoction significantly inhibited the expression of IL-1β and TNF-α mRNA in the wound tissue (P < 0.05), promoted the expression of TGF-β1 and IL-10 mRNA (P < 0.05), and the number of AC in the wound after treatment with Huiyang Shengji Decoction was less than that in the model group (P < 0.05). In the in vitro experiment, compared with the model group, the protein expression of Axl and Mertk in BMDC in the 20% Huiyang Shengji Decoction-containing serum group was significantly increased (P < 0.01, P < 0.001), and the protein expression of Tyro3 in the 5%, 10%, and 20% Huiyang Shengji Decoction-containing serum groups was higher than that in the model group (P < 0.01, P < 0.001). The phagocytic rate of AC in the Huiyang Shengji Decoction group was higher than that in the model group (P < 0.05).

CONCLUSION Huiyang Shengji Decoction can enhance the efferocytosis function of dendritic cells (DC), reduce AC aggregation in the wound, promote the disappearance of wound inflammation and tissue repair, and accelerate the healing of skin wounds.