| 摘要: |
| 目的 探讨电离辐射(ionizing radiation, IR)致小鼠皮肤创面愈合延迟可能的细胞因子机制。方法 68 只雌性昆明种小鼠随机分为两组(n=34):实验组接受 6 Gy60Co γ 射线全身照射后即刻制作背部皮肤缺损；对照组小鼠不接受辐照,同期制作背部皮肤缺损。伤后 2、4、6、8、10、12、14 d 连续描记小鼠(n=10)伤口面积,观察伤口愈合率变化。伤后 1、3、5、7 d分别处死小鼠(每个时间点各 6 只小鼠),取创面周围皮肤及下方的薄层肌肉组织,H E 染色评价伤口愈合情况；免疫组化和real time PCR 检测小鼠皮肤缺损组织血小板衍生生长因子BB (PDGF BB)、肿瘤坏死因子α(TNF-α)的表达水平。结果 致伤后 14 d 内各时间点,实验组伤口愈合率均低于对照组(P<0.01)；14 d 时实验组伤口愈合率为61.61%,对照组为90.13%,差异有统计学意义(P<0.01)。H E 染色显示:与对照组相比,实验组伤口内炎性细胞浸润明显,胶原纤维排列无序,成纤维细胞增生减少。免疫组化和real-time PCR 结果显示:伤后 3～7 d 实验组 PDGF BB蛋白表达低于对照组,差异有统计学意义 (P<0.05)；伤后 3 d,实验组PDGF-BB基因表达低于对照组 (P<0.01)。致伤后两组小鼠 TNF-α蛋白及基因表达均上调,5 d 达高峰,其后开始下降；伤后7 d 时实验组 TNF-α蛋白及基因表达均高于对照组(P<0.01)。结论 PDGF-BB、TNF-α 参与了IR 致小鼠背部皮肤缺损愈合延迟。 |
| 关键词: 电离辐射 血小板源性生长因子BB 肿瘤坏死因子α 伤口愈合 |
| DOI： |
| 投稿时间：2013-06-17修订日期：2013-08-03 |
| 基金项目:〗全军医学科技“十二五”科研项目(CWS11J300),上海市科委产学研医合作项目(12DZ1940503),上海市科委医学引导类项目(114119b2300),第二军医大学青年启动基金(2010QN21). |
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| PDGF BB and TNF α are involved in delayed skin wound healing in mice exposed to ionizing radiation |
| WANG Guo-dong1△,WANG Jia-qi1△,ZHAO Yun-fu1,BAI Shu-bo2,CHEN Xiao-qing1,WU Yang1*,WANG Da-lin3* |
(1. Department of Stomatology, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
2. Department of Stomatology, No.85 Hospital of PLA, Shanghai 200052, China
3. Department of Stomatology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
△Co-first authors.
*Corresponding authors.) |
| Abstract: |
| Objective To explore the possible cytokine mechanism of delayed skin wound healing in mice exposed to ionizing radiation(IR), so as to provide evidence for further research. Methods Totally 68 female Kunming mice were randomly divided into two groups. Back skin defect was made in mice of the experimental group (n=34) immediately after exposure to 6 Gy60n=34) had skin defect but with no radiation exposure. Wound areas were continuously measured and wound healing rates were monitored on day 2, 4, 6, 8, 10, 12, and 14 after damage (n=10). Mice were sacrificed on day 1, 3, 5, and 7 (each time point 6 mice), the skin and thin layer of muscle tissues around the wound were obtained, and H E staining was used for evaluating wound healing. Platelet derived growth factor BB （PDGF-BB） and tumor necrosis factor alpha (TNF-α) expression levels in the dermal defects were examined by immunohistochemical methods and real time PCR. Results The wound healing rate in the experimental group was significantly lower than that in the control group within 14 days after damage(P<0.01). On day 14 the wound healing rate in the experimental group was significantly lower than that in the control group (61.61% and 90.13%, P<0.01). H E staining showed more severe inflammatory cell infiltration, disarranged collagen fibers and less proliferation of fibroblasts in the wound of experimental group compared with that of the control group. Immunohistochemical and real time PCR results demonstrated that PDGF BB expression in experimental group was significantly less than that in the control group from day 3 to day 7 (P<0.05). PDGF-BB gene expression in experimental group was less than that in the control group from day 3 (P<0.01). The expression of TNF α protein and gene was up regulated in both groups and reached the peak on day 5, then began to decrease. On day 7, TNF α protein and gene expression in the experimental group was significantly higher than that in the control group (P<0.01). Conclusion PDGF-BB and TNF-α participate in delayed wound healing in ionizing radiation mice with dermal defects. |
| Key words: ionizing radiation platelet derived growth factor BB tumor necrosis factor alpha wound healing |
