Nie Kaiyu, Hu Peng, Wang Dali, Wei Zairong, Zeng Xueqin, Sun Guangfeng
Department of Burns and Plastic Surgery, the Affiliated Hospital of Zunyi Medical College, Zunyi Guizhou, 563000,
Department of Burns and Plastic Surgery, the Affiliated Hospital of Zunyi Medical College, Zunyi Guizhou, 563000, P.R.China.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2017 Jun 15;31(6):718-722. doi: 10.7507/1002-1892.201608081.
To explore the effect and mechanism of rapamycin and deferoxamin on wound healing after ischemia and hypoxia.
The model of ischemia and hypoxia wound was made on the back of 40 SPF male adult Sprague Dawley rats, weight (300±20) g; they were randomly divided into 4 groups ( =10): the control group (group A), deferoxamine intervention group (group B), rapamycin intervention group (group C), and deferoxamine+rapamycin intervention group (group D). At 3, 6, and 9 days after model preparation, rats of groups A, B, C, and D were intra-peritoneally injected with normal saline, deferoxamin (10 mg/kg), rapamycin (3 mg/kg), deferoxamin (10 mg/kg)+rapamycin (3 mg/kg) respectively. The wound healing was observed and the healing time was recorded in each group; the wound healing tissue was harvested to test the mRNA and protein expressions of mammalian target of rapamycin (mTOR), hypoxia inducible factor 1α (HIF-1α), and vascular endothelial growth factor (VEGF) by real-time fluorescence quantitative PCR and Western blot at 2 days after wound healing.
All rats survived to the end of the experiment, and wounds healed; the healing time of groups A, B, and D was significantly shorter than that of group C ( <0.05), but there was no significant difference between groups A, B, and D ( >0.05). Real-time fluorescence quantitative PCR showed that the expression of mTOR mRNA in groups C and D was significantly decreased when compared with the expressions in groups A and B ( <0.05); there was significant difference between groups A and B ( <0.05), but no significant difference between groups C and D ( >0.05). The expressions of HIF-1α mRNA and VEGF mRNA were signi-ficantly higher in groups B and D than groups A and C, and in group A than group C ( <0.05), but there was no signifi-cant difference between groups B and D ( >0.05). Western blot showed that the relative expressions of mTOR protein in groups C and D were significantly decreased when compared with the expressions in groups A and B ( <0.05), but there was no significant difference between groups C and D ( >0.05). The relative expressions of HIF-1α protein in groups A, B, and C were significantly increased when compared with expression in group D ( <0.05), but there was no significant difference between groups A, B, and C ( >0.05). The relative expression of VEGF protein were significantly lower in groups B, C, and D than group A, in group D than groups B and C, and in group C than group B ( <0.05).
Defe-roxamin can promote the wound healing of rats after ischemia and hypoxia, and the effect of rapamycin is opposite. It may be related to the existence of mTOR and HIF-1 signaling pathway in chronic ischemia-hypoxia wound.
探讨雷帕霉素和去铁胺对缺血缺氧后伤口愈合的影响及机制。
选取40只体重（300±20）g的SPF级成年雄性Sprague Dawley大鼠，在其背部制作缺血缺氧伤口模型；将大鼠随机分为4组（每组n = 10）：对照组（A组）、去铁胺干预组（B组）、雷帕霉素干预组（C组）、去铁胺+雷帕霉素干预组（D组）。模型制备后第3、6、9天，A、B、C、D组大鼠分别腹腔注射生理盐水、去铁胺（10 mg/kg）、雷帕霉素（3 mg/kg）、去铁胺（10 mg/kg）+雷帕霉素（3 mg/kg）。观察各组伤口愈合情况并记录愈合时间；伤口愈合2天后，取伤口愈合组织，采用实时荧光定量PCR和蛋白质免疫印迹法检测雷帕霉素靶蛋白（mTOR）、缺氧诱导因子1α（HIF-1α）和血管内皮生长因子（VEGF）的mRNA和蛋白表达。
所有大鼠均存活至实验结束，伤口均愈合；A、B、D组愈合时间均显著短于C组（P < 0.05），但A、B、D组之间差异无统计学意义（P > 0.05）。实时荧光定量PCR结果显示，C组和D组mTOR mRNA表达较A组和B组显著降低（P < 0.05）；A组和B组之间差异有统计学意义（P < 0.05），但C组和D组之间差异无统计学意义（P > 0.05）。B组和D组HIF-1α mRNA和VEGF mRNA表达显著高于A组和C组，A组高于C组（P < 0.05），但B组和D组之间差异无统计学意义（P > 0.05）。蛋白质免疫印迹法结果显示，C组和D组mTOR蛋白相对表达较A组和B组显著降低（P < 0.05），但C组和D组之间差异无统计学意义（P > 0.05）。A组、B组和C组HIF-1α蛋白相对表达较D组显著升高（P < 0.05），但A组、B组和C组之间差异无统计学意义（P > 0.05）。B组、C组和D组VEGF蛋白相对表达显著低于A组，D组低于B组和C组且C组低于B组（P < 0.05）。
去铁胺可促进大鼠缺血缺氧后伤口愈合，雷帕霉素作用相反。这可能与慢性缺血缺氧伤口中mTOR和HIF-1信号通路的存在有关。
