Gingiva-derived mesenchymal stem cells in repair of traumatic oral ulcer
Zhao Liru1, Xu Shukui1, Wu Yifan2, Luo Yaxian2, Shang Linlin2, Li Wenwen1, Ma Wensheng1
1Department of Orthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of Stomatology, Hebei Medical University, Shijiazhuang 050017, Hebei Province, China; 2School of Stomatology, Hebei Medical University, Shijiazhuang 050017, Hebei Province, China
Abstract: BACKGROUND: Gingiva-derived mesenchymal stem cells can promote the wound healing of skin tissue. However, it has not been clearly reported whether it has a potential therapeutic effect on oral ulcers.
OBJECTIVE: To study the therapeutic potential of gingiva-derived mesenchymal stem cells in traumatic oral ulcer.
METHODS: The animal models of oral ulcer in 21 SD rats were established by mechanical combined with chemical method. They were randomly divided into two groups: ulcer group containing 11 rat, and gingiva-derived mesenchymal stem cell group containing 10 rats. A total of 1×106 gingiva-derived mesenchymal stem cells were injected at ulcer center and surrounding area in every rat of gingiva-derived mesenchymal stem cell group at 2 days after model establishment. The rats in ulcer group were injected with the same amount of PBS. Only one rat in ulcer group was executed one day after modeling to observe the formation of ulcer. The other rats were executed 3 and 7 days after modeling, 5 rats in each group at different time points. Ulcer healing was observed by gross observation and histology.
RESULTS AND CONCLUSION: (1) Gingiva-derived mesenchymal stem cells cultured in vitro showed spindle-like structure, similar to fibroblasts, presenting full cell body with osteogenic and adipogenic differentiation potential. (2) The model of oral ulcer could be successfully established by mechanical combined with chemical method. During natural healing of ulcer group, the inflammatory reaction of the ulcer reached its most severe on day 3. On day 7, the ulcer showed a healing trend, but had not achieved completely healing. (3) On day 3 after modeling, the inflammatory response of the ulcer group was stronger than that of the gingiva-derived mesenchymal stem cell group. On day 7, the ulcer wound in the gingiva-derived mesenchymal stem cell group had achieved basically healing. (4) The hematoxylin-eosin staining showed the formation of thin epithelium at the ulcer in the gingiva-derived mesenchymal stem cell group on day 7. Masson staining results showed that the collagen formation in the gingiva-derived mesenchymal stem cell group was thicker and more regular than that in the ulcer group on day 7 after modeling. (5) These results suggest that gingiva-derived mesenchymal stem cells can reduce the inflammatory response in the early stage of traumatic oral ulcer in rats and promote the healing process of oral ulcer. The formation time of the oral epithelium is earlier, and the collagen formation is thicker and the arrangement is more regular.
Key words: gingiva-derived mesenchymal stem cell, gingival stem cell, mesenchymal stem cell, oral stem cell, traumatic oral ulcer, oral ulcer, ulcer