Hepcidin and inflammatory bowel disease: dual role in host defence and iron homoeostasis.
OBJECTIVE
Hepcidin is an endogenous antimicrobial peptide with a key role in iron homoeostasis. Hepcidin is similar to defensin, the deficiency of which is associated with Crohn's disease. To date there has been no validated method to reliably assay serum hepcidin. We studied iron indices in inflammatory bowel disease (IBD) including hepcidin.


METHODS
We assessed serum hepcidin concentrations (using a newly developed competitive radioimmunoassay) and ferritin in patients with IBD. Haematinics including serum soluble transferrin receptor, serum iron, serum vitamin B12 and red cell folate levels were also measured. The hepcidin results were compared with a control group of healthy volunteers from the local community.


METHODS
This study was based in a hospital.


METHODS
Sixty-one patients with IBD (51 patients with ulcerative colitis and 10 with Crohn's disease). Their mean hepcidin results were compared with 25 healthy controls.


METHODS
hepcidin concentration in serum samples in IBD patients compared with normal volunteers.


RESULTS
We found significantly low serum hepcidin levels in patients with IBD. The hepcidin levels were low in IBD patients without iron deficiency anaemia as evidenced by normal ferritin and serum iron levels (n=41, mean hepcidin 6.81 ng/ml, SEM 1.2) and in IBD patients with iron deficiency anaemia (n=18, mean hepcidin 4.14 ng/ml, SEM 0.72) compared with healthy controls (n=25, mean hepcidin 15.3 ng/ml, SEM 3.14) (P=0.0045 and P=0.0050 on unpaired t-tests, respectively). We also measured IL-6 (enzyme-linked immunosorbent assay method, Abcam plc) in 21 of the 61 patients with IBD and compared the results with samples from 10 healthy volunteers. The IL-6 level was significantly higher (P=0.0222 on unpaired t-tests) in this group of IBD patients (n=21, IL-6 mean 2.94 pg/ml, SEM 0.64) compared with controls (n=10, IL-6 mean 0.663 pg/ml SEM 0.14). A significant positive correlation (Pearson's correlation coefficient r=0.6331) was present between hepcidin and IL-6, but not between hepcidin and serum soluble transferrin receptor (r=-0.235).


CONCLUSIONS
The low hepcidin results in IBD patients may reflect a causal or perpetuator effect on intestinal inflammation.
Arnold
Jayantha
J
Ealing Hospital NHS Trust, Southall, UK. jay.arnold@eht.nhs.uk
Sangwaiya
Arvind
A
Bhatkal
Bharati
B
Geoghegan
Frank
F
Busbridge
Mark
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023181:Antimicrobial Cationic Peptides / Q000097:blood / Q000502:physiology*; D016022:Case-Control Studies; D005293:Ferritins / Q000097:blood; D064451:Hepcidins; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D007501:Iron / Q000097:blood*; D008875:Middle Aged; D011863:Radioimmunoassay / Q000379:methods; D055815:Young Adult
D023181:Antimicrobial Cationic Peptides; C578702:HAMP protein, human; D064451:Hepcidins; D015850:Interleukin-6; D005293:Ferritins; D007501:Iron