Institute for Cancer Studies, University of Birmingham Cancer Research, UK.
Eur J Gastroenterol Hepatol. 2009 Jul;21(7):794-804. doi: 10.1097/MEG.0b013e328308676b.
Sixty percent of people with coeliac disease (CD) are iron deficient. Many, however, remain iron replete despite the disease.
(i) To characterize the changes in duodenal iron transport proteins in CD with and without iron deficiency. (ii) To examine if iron-activated gut lymphocytes can inhibit iron export in an enterocyte cell model.
Endoscopic duodenal biopsies were collected from patients with normal duodenum with and without iron deficiency anaemia and untreated CD sufferers with iron deficiency (n=10 each group). mRNA expression of iron transport proteins was determined by quantitative real time PCR. Protein localization and expression was determined from histology sections in patients with normal duodenum (n=20), and patients with untreated CD with and without iron deficiency (n=20). In addition, CaCo2 cells were cocultured with iron-activated lymphocytes 55Fe was used to determine the effect on CaCo2 cell iron transport.
The expression of divalent metal transporter 1 and ferroportin was increased in CD with or without iron deficiency. Ferritin expression was increased in CD but only in those with associated iron deficiency. TNF-alpha produced by activated lymphocytes inhibited iron export from CaCo2 cells.
Increased enterocyte ferritin expression may promote iron deficiency in CD and this effect seems to be dependent upon TNF-alpha expression in gut lymphocytes.
60%的乳糜泻(CD)患者存在缺铁现象。然而,尽管患有这种疾病,许多患者的铁含量仍然充足。
(i)描述 CD 患者中存在和不存在缺铁现象时十二指肠铁转运蛋白的变化。(ii)检测铁激活的肠道淋巴细胞是否能在肠上皮细胞模型中抑制铁输出。
收集 10 名正常十二指肠且不伴缺铁性贫血的患者、10 名伴缺铁性贫血的未治疗 CD 患者的内镜十二指肠活检组织。采用实时定量 PCR 法测定铁转运蛋白的 mRNA 表达。从正常十二指肠患者(n=20)和未治疗 CD 患者伴或不伴缺铁(n=20)的组织学切片中测定铁转运蛋白的蛋白定位和表达。此外,将 CaCo2 细胞与铁激活的淋巴细胞共培养,并用 55Fe 来确定其对 CaCo2 细胞铁转运的影响。
铁转运蛋白 1 和亚铁转运蛋白的表达在 CD 患者伴或不伴缺铁时均增加。铁蛋白的表达在 CD 患者中增加,但仅在伴有铁缺乏的患者中增加。激活的淋巴细胞产生的 TNF-α可抑制 CaCo2 细胞的铁输出。
肠上皮细胞铁蛋白表达的增加可能会促进 CD 患者发生缺铁,而这种作用似乎依赖于肠道淋巴细胞中 TNF-α的表达。