雌激素诱导外周血间充质干细胞动员和归巢促进失血性休克大鼠创面愈合的作用

Effects of estrogen on promoting the wound healing of hemorrhagic shock rats by arousing homing of mesenchymal stem cells

目的:观察雌激素动员外周血间充质干细胞归巢对失血性休克大鼠皮肤创面愈合的影响。方法:制备失血性休克SD大鼠模型,在其背部正中线两侧各制作一个全层皮肤缺损创面(直径2 cm)。96只大鼠随机分为4组:假手术对照组(予动、静脉插管但不放血、不补液)、失血性休克组(失血性休克模型大鼠以2:1的乳酸林格液和羟乙基淀粉行常规液体复苏)、雌激素低剂量组(给予失血性休克大鼠雌激素0.2 mg/kg+常规液体复苏)、雌激素高剂量组(给予失血性休克大鼠雌激素0.5 mg/kg+常规液体复苏)。观察不同时相点各组动物皮肤创面愈合程度、愈合时间、组织血流量、ATP酶活性以及间充质干细胞动员、归巢情况。结果:与假手术对照组相比,失血性休克大鼠皮肤创面愈合缓慢,在第4天、第8天愈合率分别为(15.40±0.01)%、(36.80±1.25)%(P<0.05),组织血流量及ATP酶活性明显降低(P<0.01)。雌激素能明显促进皮肤创面的愈合,显著改善组织血流量,增强ATP酶活性,增加受损皮肤组织和血液中间充质干细胞的数量。与失血性休克大鼠相比,低剂量雌激素组第4天、第8天皮肤创面愈合率分别为(22.10±0.01)%、(46.40±1.25)%,其外周血及受损皮肤组织中间充质干细胞数量明显增多,同假手术组第4天创面愈合率[(37.10±4.32)%]、第8天创面愈合率[(67.70±1.79)%]相比,愈合仍较为缓慢(P<0.05);高剂量雌激素具有更好的促创面愈合效果,其第4天、8天创面愈合率分别为(28.40±0.12)%、(57.30±2.01)%(P<0.05),且间充质干细胞在皮肤创面及外周血中增多更为显著。失血性休克组创面完全愈合时间[(23.98±1.56)d]较假手术对照组[(14.98±1.21)d]显著延长(P<0.01),高剂量雌激素组(16.87±1.56)d和低剂量雌激素组[(22.67±1.78)d]创面愈合时间明显缩短(P<0.05),且高剂量雌激素组创面愈合时间最短。结论:雌激素可动员间充质干细胞归巢,促进失血性休克大鼠创面愈合。

Objective： To investigate the effects of estrogen on promoting wound healing of hemorrhagic shock rats by arousing homing of mesenchymal stem cells （MSCs）. Methods： SD rats were used to establish the hemorrhagic shock models by full-thickness skin defect with 2 cm diameter made at each side of dorsal middle line. Ninety-six model rats were randomly divided into 4 groups： sham operation group （intubation in artery and vein, but no bleeding and fluid infusion）, hemorrhagic shock group （conventional fluid resuscitation with 2：1 of lactated Ringer＇s solution ＋ hydroxyethyl starch）, low-dose estrogen group （estrogen 0.2 mg/kg and conventional resuscitation） and high-dose estrogen group （estrogen 0.5 mg/kg and conventional resuscitation）. The skin wound healing time, healing rate, tissue blood flow, ATPase activity and the mobilization and homing of MSCs in skin and peripheral blood were observed. Results： Compared with the sham operation group, the skin wound healing was slower in hemorrhagic shock group （P〈0.05）, the healing rates were （15.40±0.01）% on day 4 and （36.80±1.25）% on day 8, respectively; and the ATPase activity and blood flow decreased significantly （P〈0.01）. Estrogen markedly promoted the skin wound healing, obviously improved the tissue blood flow, enhanced the ATPase activity and increased the number of MSCs in damaged skin tissue and blood. In low-dose estrogen group, the skin wound healing rates rose significantly when compared with that in hemorrhagic shock group, but were still lower when compared with that in sham operation group at day 4 [（22.10±0.01）% vs. （37.10±4.32）%] and day 8 [（46.4±1.25）% vs. （67.70±1.79）%, P〈0.05], and the number of MSCs in peripheral blood and damaged skin tissues increased significantly. High-dose estrogen showed better effects than low-dose estrogen on promoting wound healing, reached healing rates of （28.40 ± 0.12）% and （57.3 ± 2.01）% at day 4 and day 8, respectively, and showed more obviously increase of MSCs in skin wound and peripheral blood. The wound healing time in the hemorrhagic shock group [（23.98±1.56） days] was significantly longer than in the sham operation group [（14.98±1.21） days, P〈0.01], the wound healing time significantly reduced in high-dose estrogen group [（16.87±1.56） days] and low-dose estrogen group [（22.67±1.78） days, P〈0.05], and was the shortest in high-dose estrogen group. Conclusions： Estrogen can mobilize MSCs homing and promote the wound healing of damaged tissues of hemorrhagic shock rats.