基质金属蛋白酶-7基因在幽门螺杆菌相关性胃十二指肠疾病儿童胃黏膜中的表达

Expression of Matrix Metalloproteinase-7 Gene in Gastric Mucosa of Children with Upper Gastrointestinal Disease Infected with Helicobacter Pylori

目的探讨基质金属蛋白酶-7(MMP-7)基因在幽门螺杆菌(Hp)相关性胃十二指肠疾病儿童胃黏膜中的表达。方法具有上消化道不适主诉症状的患儿96例(包括慢性胃炎66例及十二指肠溃疡30例),经上消化道内镜检查获取其胃窦黏膜活检标本。根据Sydney胃炎标准对HE染色的活检组织进行胃窦黏膜慢性炎症程度评价。以血清Hp-IgG抗体检测、胃黏膜PCR、尿素酶试验及组织学检查结果作为确定Hp感染状态的依据。患儿均采用RT-PCR法及免疫组织化学法检测其胃窦黏膜MMP-7的表达。结果96例患儿的Hp感染率为51.0%。免疫组织化学染色结果显示MMP-7主要在胃上皮细胞中表达。Hp感染者的胃窦黏膜MMP-7mRNA及蛋白的阳性表达率(87.8%及89.8%)与无Hp感染者的阳性表达率(70.2%及63.8%)比较差异均有统计学意义(Pa<0.05)。Hp感染者胃窦黏膜MMP-7mRNA表达水平较无Hp感染者高(P<0.05),其表达水平与胃窦黏膜的慢性炎症程度呈正相关(r=0.312,P<0.05)。结论Hp感染诱发儿童胃十二指肠疾病胃窦黏膜中MMP-7基因的表达,推测基因表达的增高是Hp感染的早期事件,其主要作用可能是促进了Hp相关性胃十二指肠疾病患儿胃黏膜的破坏。

Objective To explore the expression of matrix metalloproteinase-7 （MMP-7） gene in gastric mucosa of children with upper gastrointestinal disease infected with Helicobacter pylori （Hp）.Methods Gastric biopsies were obtained from 96 children with dyspeptic symptoms.MMP-7 expression in gastric was assessed in 66 children with chronic gastritis and 30 children with duodenal ulcer by adopting reverse transcription-polymerase chain reaction （RT-PCR） and immunohistochemistry.Biopsy specimens were stained with hematoxilin and eosin （HE）,and the degree of antrum chronic inflammation was graded according to the Sydney system.Serology,PCR,urease test and histo-logy were used to assess Hp infection status.Results The infection rate in 96 children with upper gastrointestinal disease was 51.0%.The results of immunohistochemistry demonstrated that MMP-7 was predominantly observed at gastric epithelial cells.The positive expression rates of MMP-7 mRNA and protein in gastric mucosa were detected in Hp infected children （87.8% and 89.8%） and in uninfected children （70.2% and 63.8%）,and there were significant differences between the 2 groups（Pa0.05）.The level of MMP-7 mRNA expression was higher in Hp infected children than that in uninfected children（P0.05）,and there was significantly positive correlation with the degree of antrum chronic inflammation（r=0.312,P0.05）.Conclusions Hp can induce the expression of MMP-7 in gastric mucosa in children.The increased expression of MMP-7 production is speculated to be an early event in the response to gastric Hp infection,a feature that may contri-bute to gastric mucosa damage during Hp-associated upper gastrointestinal disease in children.