SDF-1在拔牙创软组织愈合过程中的表达及分布

Expression and distribution of SDF-1 in the soft tissue healing of tooth extraction

目的:观察拔牙创软组织内基质细胞衍生因子l(SDF-1)的表达及分布,为促进拔牙创愈合提供新思路。方法:Wistar雄性大鼠30只,随机分为10组,每组3只,分别拔除左侧下颌第一磨牙。于拔牙后1、2、4、7、10 d分别采用免疫组织化学染色和RT-PCR技术观察SDF-1在创缘软组织内的分布及表达变化情况。采用SPSS12.0软件包对数据进行统计学分析。结果:免疫组织化学染色显示,拔牙早期创口周围牙龈组织内SDF-1表达增强,染色部位主要分布于牙龈上皮的棘层及基底层细胞胞质与细胞间。越靠近基底层细胞,染色越明显。拔牙后4 d,阳性染色部位主要位于基底细胞层,新生肉芽组织内可见新生血管的内皮细胞和增殖活跃的成纤维细胞阳性表达。拔牙后7 d,牙龈上皮细胞层染色变得均匀,固有层可见少量阳性染色的新生血管内皮细胞及成纤维细胞;拔牙后10 d,牙龈上皮染色特点基本与正常牙龈相似。实时定量PCR检测结果表明,SDF-1m RNA的表达水平在拔牙后1 d达到最高(P<0.01),第2天开始下降(P<0.05),拔牙后4 d出现第2次峰值(P<0.01),7 d后其表达水平仍高于对照组(P<0.05),10 d时恢复正常水平(P>0.05)。结论:SDF-1参与拔牙创软组织的早期愈合过程,可能对拔牙创的愈合起着一定的促进作用。

PURPOSE： To observe the expression and distribution of stromal cell derived factor -1 （SDF-1） in the soft tissues after tooth extraction, in order to provide new ideas to promote wound healing of tooth extraction. METHODS： Thirty male Wistar rats were randomly divided into 10 groups. After extracting the first molar of left mandibular respectively, immunohistochemistry and RT-PCR technique were used to evaluate the distribution and expression of SDF-1 1, 2, 4, 7 and 10 days after extraction. Data processing was performed using SPSS 12.0 software package. RESULTS： Immunohistochemical staining showed the SDF-1 protein was strongly expressed at the gingival tissues around tooth extraction wound at early stage, mainly in the cytoplasm and intercellular substance of the stratum spinosum and stratum basale, and stained more obviously closer to the stratum basale. Four days after tooth extraction, the expression of SDF-1 in the stratum basale became more evident, and it is also positive inside endothelial cells of granulation tissues. Seven days after tooth extraction, the staining became uniform in the gingival epithelium, and a few positive staining of vascular endothelial cells could be found in lamina propria; Ten days after tooth extraction, the staining characteristics were similar to the normal gingiva. RT-PCR results showed that SDF-lmRNA underwent a biphasic expression change during gingival wound healing. SDF-1 mRNA level reached peak at day 1 after tooth extraction （P〈0.01） but decreased by day 2. However, the SDF-1 mRNA level increased again to a peak at day 4 and then returned to a normal level by day 10 （P〉 0.05）. CONCLUSIONS： SDF-1 is involved in the early soft tissue healing process, and may play a role as a promoter in tooth extraction healing.Supported by Young Scientists Award Fund of Shangdong Province （BS2013YY056） and Sci-tech Development Planning Program of Jinan City （2013-60）.