Periodontitis is a common oral disease caused by bacteria coupled with an excessive host immune response. Stem cell therapy can be a promising treatment strategy for periodontitis, but the relevant mechanism is complicated. This study aimed to explore the therapeutic potential of mitochondria from human embryonic stem cell-derived mesenchymal stem cells (hESC-MSCs) for the treatment of periodontitis. The gingival tissues of periodontitis patients are characterized by abnormal mitochondrial structure. Human gingival fibroblasts (HGFs) were exposed to 5 μg/mL lipopolysaccharide (LPS) for 24 h to establish a cell injury model. When treated with hESC-MSCs or mitochondria derived from hESC-MSCs, HGFs showed reduced expression of inflammatory genes, increased adenosine triphosphate (ATP) level, decreased reactive oxygen species (ROS) production, and enhanced mitochondrial function compared to the control. The average efficiency of isolated mitochondrial transfer by hESC-MSCs was determined to be 8.93%. Besides, a therapy of local mitochondrial injection in mice with LPS-induced periodontitis showed a reduction in inflammatory gene expression, as well as an increase in both the mitochondrial number and the aspect ratio in gingival tissues. In conclusion, our results indicate that mitochondria derived from hESC-MSCs can reduce the inflammatory response and improve mitochondrial function in HGFs, suggesting that the transfer of mitochondria between hESC-MSCs and HGFs serves as a potential mechanism underlying the therapeutic effect of stem cells.
Humans ; Gingiva/cytology* ; Fibroblasts/metabolism* ; Mitochondria/physiology* ; Mesenchymal Stem Cells/cytology* ; Animals ; Periodontitis/therapy* ; Mice ; Reactive Oxygen Species/metabolism* ; Inflammation ; Lipopolysaccharides ; Human Embryonic Stem Cells/cytology* ; Cells, Cultured ; Adenosine Triphosphate/metabolism* ; Male

Objective: To explore the choice of the donor site of flap and the repair method of secondary wound of flap donor site in tissue repair and reconstruction operation. Methods: From January 2014 to September 2018, 62 cases of scar contracture deformity, 15 cases of skin tumor, 20 cases of skin and soft tissue injury, and 25 cases of chronic wound were admitted to the Burn Center of People′s Liberation Army of First Affiliated Hospital of Air Force Medical University, with 84 males and 38 females, aged from 3 to 89 years. Four repair strategies adopted for tissue repair and reconstruction and good repair of the donor site of flap were as follows: designing the flap rationally according to the condition around the wound or the size and shape of wound, choosing pre-expanded technique of the donor site of flap for repair of scar deformity optimally, making full use of the surrounding condition of flap donor site, and repaired with the distal flap, i. e. replacing the important site with secondary site. The donor site of flap was repaired by direct suture or peripheral flap and distal flap. The wound size of patients ranged from 3.0 cm×2.0 cm to 20.0 cm×18.0 cm, and the flap area ranged from 3.5 cm×2.0 cm to 25.0 cm×22.0 cm. The survival condition of flap, healing condition of donor site and recipient site, and follow-up condition of donor site and recipient site were recorded. Results: Wounds of 122 patients were repaired with a total of 148 flaps designed by the above four repair strategies. All the flaps survived well, and the wound and flap donor site healed well. Follow-up for 3 to 36 months showed that the shape and function of recipient site and flap donor site were satisfactory. Conclusions According to the specific condition of the wound and anatomical structure of the surrounding tissue of flap donor site, overall surgical design with flexibility and personalization can achieve effects of good repair of the wound and reduce the secondary damage of flap donor site.

OBJECTIVE: To evaluate the advantage of Gukangling Decoction (GKLD), a compound traditional Chinese herbal medicine, combined with technetium [(99)Tc] methylene diphosphonate injection ((99)Tc-MDP) in treating osteoporosis in rabbits. METHODS: A rabbit model of osteoporosis was established by intramuscular injection of dexamethasone (DX). Fifty-six rabbits were divided into 8 groups: Group A, B, C, D, E, F, G and H. Rabbits in groups A and B were intramuscularly injected normal saline as normal control, groups C and D were untreated groups, rabbits in group E were treated by (99)-MDP, rabbits in group F were treated by aminodiphosphate, rabbits in group G were treated by GKLD, and rabbits in group H were treated by (99)-MDP and GKLD. Rabbits in groups A and C were executed to demonstrate the establishment of the rabbit model of osteoporosis at the 8th week of experiment. Rabbits in the other six groups were executed after 16-week experiment (8-week treatment), and then bone structure and cell shape were observed by electron microscope, X-ray, CT and emission computed tomography (ECT). Bone density, biomechanical parameters, the levels of bone specific alkaline phosphatase (BALP) and bone Gla protein (BGP) were measured too. RESULTS: After 8-week of intramuscular injection of DX, the bone trabecula in group A were regular and showed normal configuration, while the bone trabecula in group C were sparse, ruptured and showed damaged form. The bone density and biomechanical parameters in group A were higher than those in group C, indicating that the rabbit model of osteoporosis was established successfully. At the 9th week of experiment, the results of cell pathology in group D showed that the bone trabeculas were sparse, ruptured, defected or had hollow section, but the bone trabeculas in group B were regular and dense. The bone trabeculas in groups H and E were restored, and were thicker than those in group D. The bone quality in groups H and E was better than group D significantly, the bone quality in group F was better than group G, and the bone quality in group G was better than group D slightly. CONCLUSION: GKLD combined with (99)-MDP had superiority in treating osteoporosis of rabbits as compared with the respective single therapy.