Objective: Few studies have been carried out on the trace element status in patients with ulcerative colitis (UC). Many trace elements are critical for the normal development and function of the immune system. This study was conducted in order to assess the serum levels of zinc and copper and the possible interrelation(s) between them and various immunological markers in the circulation of well nourished patients with UC.
Design/methods: The serum levels of zinc, copper, soluble interleukin-2 receptors (sIL-2Rs), interleukin-1beta (IL-1beta), interleukin-2 (IL-2), tumour necrosis factor-alpha (TNF-alpha), non-organ specific autoantibodies (RF, ANA, ANCA, anti-dsDNA and anticardiolipin), C3C and C4 components of the complement system and ceruloplasmin were determined in 75 well nourished patients with UC (32 patients with active and 43 with inactive disease). Thirty-three healthy individuals were also investigated.
Results: The mean concentrations (microg/dl) of zinc and copper were significantly higher (P < 0.0005 and P = 0.0001, respectively) either in active (202.3 +/- 115.2 and 141.7 +/- 31.4, respectively) or in inactive disease (204.5 +/- 170.3 and 137.4 +/- 24.5, respectively) compared with healthy controls (93.6 +/- 49.8 and 85 +/- 41.2, respectively). The levels of copper were positively correlated with the C3C (r = 0.41, P < 0.0005), C4 (r = 0.38, P < 0.001) and ceruloplasmin (r = 0.44, P < 0.0005), whereas zinc was correlated with C3C (r = 0.32, P = 0.0005) and ANA (P = 0.01). Autoantibodies of at least one specificity (AUBS) were found in 77.3% of the patients. The mean levels (U/ml) of sIL-2Rs were significantly higher (P = 0.0001) in active disease (604.3 +/- 213.0) than in inactive UC (411.5 +/- 165.1) and in patients with ANA (P < 0.05), ANCA (P = 0.01) or AUBS (P < 0.05). The sIL-2Rs were correlated with the C4 (r = 0.40, P < 0.005) and the ESR (r = 0.43, P = 0.0001).
Conclusion: These findings indicate that even in well nourished patients with UC, high serum levels of copper and zinc are present. The latter alterations of zinc and copper are correlated with haematological parameters of relapse of the disease or with acute phase proteins suggesting a relationship with the inflammatory process of UC. Further studies on the colonic tissue will address the role of zinc and copper in the inflammatory and immune reactions observed in this disease process.