Effect on DNA content and cell cycle of wounds by recombinant
epidermal growth factor mixed with bletilia striata gelatin

Abstract

AIM： To observe the effect on DNA content and cell cycle of back wounds by exogenous recombinant human epidermal growth factor (rhEGF) mixed with bletilia striata gelatin (BSG) in rabbits, and to explore the underlying mechanism.

METHODS：The experiment was done between March and November 2005 in the Clinical Experimental Center of Hebei Provincial People’s Hospital. Forty healthy rabbits were adopted and randomly allocated into four groups: saline group, BSG group, rhEGF group and BSG+rhEGF group, each containing 10 rats. Six full thickness skin incisions measuring 2 cm×2 cm were created on the two sides of spinal column, which were 2 cm to the wounds and 3 incision in each side. Then wounds were covered with the double-layer gauzes that were soakaged by physic liquor. Dressings were removed daily. Full-thickness of the skins was taken respectively for the observation: ①The wound healing time: Complete healing were defined as the wound area was less than 5% of total area or healing area was more than 95% of total area;②The wound healing rate: On the 3rd and 10th days postoperation, the transparent square paper of 0.25 cm×0.25 cm was used to determine wound area, and Germany ASN-68K semi-automatic image analyzer was used for calculation. Healing rate=healing area/primary area of wound×100%;③The proliferation activity of epidermal cells: Flow cytometry was applied for the DNA content and cell cycle of epidermal cells on the 5th day postoperation, proliferation index=(S+G2M)/(G0/G1+S+G2M)×100%.

RESULT: Totally 40 rabbits were involved in the result analysis.①Wound healing time was significantly shorter in BSG+rhEGF group than in saline group, BSG group and rhEGF group [(13.9±0.3), (19.3±0.7), (16.8±0.7), (17.6±0.6) days, t =7.632, 3.278, 4.563, P < 0.01, 0.05, 0.05].②On the 3rd and 10th days postopweration, the wound healing rate of BSG+rhEGF group was significantly increased, comparing with other three groups [the 3rd day: (49.83±0.03)%, (21.63±0.03)%, (36.34±0.03)%, (39.57±0.04)%, P < 0.01; the 10th day: (87.88±0.01)%, (68.40±0.02)%, (83.37±0.01)%, (78.97±0.02)%, P < 0.01, 0.05].③Proliferation activity: On the 5th day postoperation, the proliferation index was higher in BSG+rhEGF group than in other three groups, with the significant differences [(43.17±1.1)%, (31.7±1.4)%, (36.3±1.6)%, (32.59±1.5)%, P < 0.05].

CONCLUSION: BSG+rhEGF can promote the DNA synthesis of epidermal cells on wounds, elevate the proliferation, decurtate the wound time, and accelerate the wound healing.

摘要
目的：观察白芨胶作为外源性重组人表皮生长因子载体对兔背部创面表皮细胞DNA含量及周期的影响，并探讨其机制。
方法：实验于2005－03/11在河北省人民医院临床实验中心完成。选择健康家兔40只，以手术切割方法造
模，距脊柱正中旁开2 cm处做皮肤全层切口，面积约2 cm×2 cm，左右各3个。将家兔按随机数字表法分为4组，生理盐水组、白芨胶组、重组人表皮生长因子组和白芨胶+重组人表皮生长因子组，每组10只，分别给予生理盐水、白芨胶、重组人表皮生长因子和白芨胶+重组人表皮生长因子治疗。用已配好的药液浸透纱布外敷伤口，换药1次/d。取材后测定：①伤口愈合时间：伤口愈合标准以创面面积小于总面积的5%或愈合面积大于95%为完全愈合。②伤口愈合率：各组动物分别在术后第3，10天，用0.25 cm×0.25 cm的透明方格纸测定伤口面积，用德国产ASN-68K半自动图像分析仪计算伤口面积，伤口愈合速率=愈合面积/原伤口面积×100%。③表皮细胞增殖活性：用流式细胞检测方法检测术后第5天表皮细胞DNA的含量及周期变化，增殖指数=（S+G2M）/（G0/G1+S+G2M）×100%。
结果：纳入家兔40只，均进入结果分析。①伤口愈合时间：白芨胶+重组人表皮生长因子组伤口愈合时间少于生理盐水组、白芨胶组、重组人表皮生长因子组，差异有显著性意义[分别为（13.9±0.3），（19.3±0.7）,（16.8±0.7）,（17.6±0.6） d，t =7.632，3.278,4.563，P < 0.01，0.05，0.05]。②伤口愈合率：术后第3，10天，白芨胶+重组人表皮生长因子组家兔伤口愈合率高于生理盐水组、白芨胶组、重组人表皮生长因子组，差异均有显著性意义[第3天分别为（49.83±0.03）%，（21.63±0.03）%，（36.34±0.03）%，（39.57±0.04）%，P < 0.01；第10天分别为（87.88±0.01）%，（68.40±0.02）%，（83.37±0.01）%，（78.97±0.02）%，P < 0.01,0.05]。③表皮细胞增殖活性：术后第5天，白芨胶+重组人表皮生长因子组的增殖指数高于生理盐水组、白芨胶组、重组人表皮生长因子组，差异有显著性意义[分别为（43.17±1.1）%，（31.7±1.4）%，（36.3±1.6）%，（32.59±1.5）%，P < 0.05]。
结论：白芨胶+重组人表皮生长因子能显著促进创面表皮细胞DNA的合成，提高细胞的增殖能力，缩短伤口愈合时间，加速伤口愈合。
关键词：伤口愈合；白及；表皮生长因子；流式细胞术

仇树林，王晓，李兵，韩胜，朱昊.白芨胶载重组人表皮生长因子对创面表皮细胞DNA含量及周期的影响[J].中国组织工程研究与临床康复，2007，11(1):63-66 [www.zglckf.com/zglckf/ejournal/upfiles/07-1/1k-63(ps).pdf]