胎儿皮肤和增生性瘢痕组织内基质金属蛋白酶及其抑制因子表达变化的研究

发布时间：2019-04-02 11:55

【摘要】：目的：研究基质金属蛋白酶(MMPs)和基质金属蛋白酶组织抑制因子(TIMPs)在不同发育时期的胎儿皮肤和不同形成时期的增生性瘢痕中基因表达和蛋白含量、分布的变化，探索无瘢痕愈合发生机制以及增生性瘢痕发生和成熟的部分机制。方法：①胎儿皮肤因创伤等意外因素终止妊娠的胎儿背部全层皮肤，共18例，胎龄(EGA)13～33周。标本按胎龄分为3组，即早期(13～19周)，中期(21～25周)和晚期(27～33周)，每组6例。②增生性瘢痕组织取自进行整形手术患者的增生性瘢痕16例，平均年龄为26岁，伤口愈合的时间为4月～11年。瘢痕增生时间1年以内8例，1～2年4例，2年以上4例。正常对照组皮肤8例，取自病人供皮区的全层皮肤。标本经无菌取材后，一部分立即液氮冻存，用于进行逆转录-多聚酶链反应(RT-PCR)和Western blot实验，检测MMP-1，MMP-2，MMP-3，MMP-7，MMP-9，MMP-14，TIMP-1，TIMP-2和TIMP-3基因表达和蛋白含量的变化；另一部分标本经10％中性甲醛液固定，脱水，石蜡包埋后切片，用于免疫组化实验，镜下观察。结果：1．在早期妊娠胎儿皮肤中MMP-1，MMP-2，MMP-3，MMP-7，MMP-9及MMP-14的基因表达和蛋白含量均较低，随着胎龄的增加，表达水平逐渐升高，在妊娠晚期皮肤中这些基因的mRNA和蛋白含量都显著增强(P＜0.05)。TIMP-2和TIMP-3的基因表达和蛋白含量呈相同的变化趋势，随着胎儿皮肤不断发育而逐渐升高。在不同妊娠时期的胎儿皮肤中，，TIMP-1基因表达变化不显著，但蛋白含量水平则逐渐增大，在妊娠晚期皮肤内含量明显高于妊娠早期(P＜0.05)。 2．在正常皮肤组织内，MMPs和TIMPs的基因表达较弱，蛋白含量较低，蛋白阳性颗粒主要分布于表皮基底层细胞和少量的成纤维细胞中；在增殖期的瘢痕中MMPs和TIMPs基因和蛋白表达都显著升高(P＜0.05)，在成熟期的瘢痕中，MMPs基因表达量降至正常水平，但蛋白含量明显高于正常皮肤(P＜0.05)，蛋白
[Abstract]:Objective: to study the changes of gene expression, protein content and distribution of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase (TIMPs) in fetal skin and hypertrophic scars at different stages of development. To explore the mechanism of scar-free healing and some mechanisms of hypertrophic scar formation and maturation. Methods: 1Fetal skin terminating pregnancy due to trauma and other unexpected factors, 18 cases of fetal back full skin, gestational age (EGA) 13 weeks. The specimens were divided into three groups according to their gestational age: early stage (13 ~ 19 weeks), middle stage (21 ~ 25 weeks) and late stage (27 ~ 33 weeks), 6 cases in each group. 2Hypertrophic scar tissue was obtained from 16 cases of hypertrophic scar from patients undergoing plastic surgery. The mean age was 26 years and the wound healing time ranged from 4 months to 11 years. Scar hyperplasia time was less than 1 year in 8 cases, 1-2 years in 4 cases, more than 2 years in 4 cases. The normal control group (n = 8) was taken from the whole skin of the donor area of the patient. After aseptic sampling, part of the samples were frozen in liquid nitrogen immediately and used for reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay to detect MMP-1,MMP-2,MMP-3,MMP-7,MMP-9,MMP-14,TIMP-1,. Changes of TIMP-2 and TIMP-3 gene expression and protein content; The other part was fixed with 10% neutral formaldehyde solution, dehydrated and embedded in paraffin. The other part was used for immunohistochemical test and observed under microscope. Results: 1. The gene expression and protein content of MMP-1,MMP-2,MMP-3,MMP-7,MMP-9 and MMP-14 in fetal skin of early pregnancy were lower, and the expression level increased gradually with the increase of fetal age. In the third trimester of pregnancy, the mRNA and protein contents of these genes were significantly increased (P < 0.05), and the gene expression and protein content of TIMP-2 and TIMP-3 showed the same change trend, and gradually increased with the development of fetal skin. The expression of TIMP-1 gene did not change significantly in fetal skin of different pregnancy stages, but the protein content increased gradually, and the content of protein in the skin of late pregnancy was significantly higher than that in the early trimester of pregnancy (P < 0.05). 2. In normal skin tissues, the gene expression of MMPs and TIMPs was weak and the protein content was low. The positive granules of protein were mainly distributed in the basal cells of epidermis and a small number of fibroblasts. The expression of MMPs and TIMPs gene and protein in proliferative scar were significantly increased (P < 0.05). In mature scar, the expression of MMPs gene decreased to normal level, but the protein content was significantly higher than that in normal skin (P < 0.05).
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R363

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