RT Journal Article ID 3b82733a6db975f4 A1 Gu, Qingyang A1 Wang, Dewen A1 Gao, Yabing A1 Zhou, Jie A1 Peng, Ruiyun A1 Cui, Yufang A1 Xia, Guowei A1 Qing, Quanhong A1 Yang, Hong A1 Liu, Jie A1 Zhao, Meilan T1 Expression of MMP1 in Surgical and Radiation-Impaired Wound Healing and Its Effects on the Healing Process JF Journal of Environmental Pathology, Toxicology and Oncology JO JEP(T) YR 2002 FD 2002-03-01 VO 21 IS 1 OP 8 AB Radiation-impaired wound is characterized by delayed healing, nonhealing, and carcinogenesis. The mechanism remains unclear. Matrix metalloproteinases (MMPs) are one family of key regulators of the process of wound healing. Their abnormal expression plays important roles in the formation of some chronic skin ulcers. The objective of this project was to study the expression of MMP1 in surgical and radiation-impaired wound healing and its effects on the healing process and tissue remodeling. A rat model of radiation-impaired wound healing was used. Routine light microscopy, electron microscopy, immunohistochemistry, and in situ hybridization, all of which enabled the detection of MMPI expression during the healing process, were performed. The wound healing process was impaired and delayed. In rats receiving 25Gy g-ray locally, the irradiated wounds healed 6 days later than the nonirradiated controls. The following changes in MMP1 expression were found: (1) In the early inflammatory phase and in the period of granulation tissue formation, MMP1 expression was only slightly if at all affected in the newly formed epidermis of irradiated wounds compared with controls. Later, the epidermal expression of MMP1 in radiation wounds was comparatively increased following the delay of the healing process. (2) MMP1 expression in irradiated wounds was markedly decreased in fibroblasts, endothelial cells, and macrophages compared with controls. The expression phase was prolonged because of the delay of the healing process. The reduced expression of MMP1 in granulation tissue retards such important processes as cell migration, angiogenesis, and tissue remodeling, thus slowing the healing process. The expression ofMMPI in the proliferating keratinocytes may help re-epithelialization. However, in the late healing period, overexpression ofMMPI in the epidermis may hinder the establishment ofbasal membrane and the formation of granulation tissue, and affect the tissue remodeling process. PB Begell House LK https://www.dl.begellhouse.com/journals/0ff459a57a4c08d0,18179bf737097662,3b82733a6db975f4.html