Expression of Annexin A1 during Skin Incised Wound Healing in Mice

Abstract

Objectives: To investigate the expression changes of annexin A1 （ANXA1） during the process of skin incision healing, and to explore its expression and function during skin injury repair.

Methods: The skin injury model of mice was prepared, and skin tissues of the controls and the injured group at 6 h, 12 h, 1 d, 3 d, 5 d, 7 d, 10 d and 14 d after injuries were taken. The morphological changes of the wound were observed by hematoxylin-eosin （HE） staining, and the expression of ANXA1 was detected by immunohistochemistry （IHC） and Western blotting.

Results: HE staining showed normal healing of skin wounds. IHC results revealed that ANXA1 was expressed in the epidermis, hair follicle, sebaceous gland and vascular endothelium. In the injured group, the expression of ANXA1 was enhanced in epidermis and skin appendages around the wound 6-12 h after injury, and ANXA1 was also highly expressed in neutrophils and a small number of mononuclear cells. ANXA1 was mainly positively expressed in monocytes, neovascular endothelial cells and fibroblasts, and small amount of fibroblasts at 1-3 d, 5-10 d, and 14 d after injury, respectively. Western blotting showed that, compared with the controls, the expression of ANXA1 was significantly increased at 6 h after injury, peaked at 1 d, and then decreased gradually in the injured group.

Conclusions: ANXA1 may be involved in the regulation of skin damage repair, with time-dependent expression during skin wound healing, and thus is expected to be a biological marker for inferring the wound formation time.

Keywords: forensic pathology; trauma and injury; skin; annexin A1; wound age determination; mice.