儿童原发性肾病综合征激素抵抗与糖皮质激素受体基因多态性的相关性

Correlation between glucocorticoid-resistance and gene polymorphisms of glucocorticoid receptor in children with primary nephrotic syndrome

摘要:

目的：原发性肾病综合征(PNS)是常见的小儿肾脏疾病,其发病机制目前尚不清楚，研究发现，急性淋巴细胞白血病、狼疮性肾炎糖皮质激素耐药与糖皮质激素受体(GCR)突变有关。是否是由于GCR基因发生改变引起GCR功能异常，导致PNS患儿对糖皮质激素(GC)耐药，目前尚未见报道。该文探讨儿童原发性肾病综合征对糖皮质激素治疗的效应与糖皮质激素受体DNA结合区、激素结合区基因多态性的相关性。方法：采用常规方法提取100例原发性肾病综合征患儿(其中激素敏感组44例、激素抵抗组56例)及100例对照组儿童外周血单核细胞DNA，聚合酶链反应(PCR)技术扩增所有DNA，GCR DNA结合区，激素结合区全部外显子目的片断，然后进行单链构象多态性(SSCP)分析。SSCP显示异常的DNA片断直接测序。结果：激素敏感组、激素抵抗组、对照组儿童外周血GCR DNA结合区、激素结合区所有外显子PCR产物SSCP电泳结果，未发现SSCP条带多态性。结论：该研究未发现PNS患儿激素抵抗与GCR DNA结合区、激素结合区基因多态性之间存在相关性。

Abstract:

OBJECTIVE: Previous studies have shown that the reduced glucocorticoid (GC) sensitivity is associated with the mutations of glucocorticoid receptor (GCR) in patients with acute lymphocytic leukemia or with lupus nephritis. It has not been confirmed whether GC-resistance is the result of abnormal function of GCR induced by the alteration of GCR gene in children with primary nephrotic syndrome (PNS). The purpose of this study is to investigate the correlation between GC-resistance and the polymorphisms of GCR in DNA-binding domain and hormone-binding domain in children with PNS. METHODS: DNA was isolated from peripheral blood leukocytes in 100 children with PNS (44 with GC-sensitive, 56 with GC-resistance) and 100 healthy controls and each exon of the DNA-binding domain and hormone binding domain of GCR was amplified by the polymerase chain reaction (PCR). Single-strand conformation polymerase (SSCP) analysis of the PCR products was carried out for screening polymorphisms. DNA fragments displaying an abnormal migration pattern during SSC analysis were subjected to direct sequencing. RESULTS: PCR-SSCP analysis in all of the PCR products from the GC-resistance and GC-sensentivity cases did not display an abnormal DNA fragment migration pattern. Polymorphism of GCR in neither the DNA-binding domain nor the hormone-binding domain was found. CONCLUSIONS: There is no correlation between GC-resistance and the polymorphisms of GCR in DNA-binding domain and hormone-binding in children with PNS.