Publication Date:
2007-11-16
Description:
Introduction: An insufficient production of hepcidin, the master regulator of iron metabolism, is recognized as the key pathogenetic feature of HFE-related hereditary hemochromatosis (HH). There is a growing interest in measuring the hepcidin levels, which may improve diagnosis, prognostic evaluation and clinical management of HH. Nevertheless, few investigative tools are available: an immunodot method for urinary hepcidin developed by a single centre (UCLA), not yet ready for large-scale diffusion, and mass spectrometry (MS) based assays, such as surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF-MS). The latter is well suited to small peptides like hepcidin, and can rapidly analyze crude samples with high throughput. Until now, urinary hepcidin has been measured by SELDI-TOF-MS only in small groups of C282Y homozygous patients, the majority of them under phlebotomy treatment. No data are available on C282Y/H63D compound heterozygotes, that can develop a milder clinical form of HH. This study was aimed to measure urinary hepcidin levels by SELDI-TOF-MS in a large group of HH patients. Methods: We used a protocol based on PBSIIc mass spectromer and Normal Phase chips similar to that recently proven successful for semi-quantitative detection of urinary hepcidin. Urinary samples from 30 control subjects were compared to those obtained from 80 HH patients (57 C282Y homozygotes, 23 C282Y/H63D compound heterozygotes). Eighteen C282Y homozygotes and 11 C282Y/H63D compound heterozygotes were analyzed at diagnosis, the remainder during maintenance phlebotomy (at least 30 days from last phlebotomy). Results: C282Y homozygotes had significantly lower urinary hepcidin levels vs. controls either at diagnosis, or after phlebotomy (P 〈 0.05). C282Y/H63D compound heterozygotes had hepcidin levels at diagnosis similar to controls, while the hepcidin:ferritin ratio was significantly decreased (P 〈 0.001) suggesting a relatively inappropriate hepcidin production. Moreover, also in this group means hepcidin levels after phlebotomy were significantly lower than in controls (P 〈 0.001). Samples from 12 randomly selected control subjects were sent to UCLA for duplicate measurement by the immunodot method, yielding a good correlation (r= 0.77; P
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
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