Readressing the role of Toll-like receptor-4 alleles in inflammatory bowel disease: colitis, smoking, and seroreactivity.

BACKGROUND: Toll-like receptor (TLR) polymorphisms, and especially TLR-4 Asp299Gly and TLR-4 Thr399Ile, have been linked with Crohn's disease (CD) and to a lesser extent with ulcerative colitis (UC), CD behavior, and compromised seroreactivity to microbial antigens. Available data, however, are conflicting. AIMS: To address these issues, the distribution of TLR-4 polymorphic alleles was assessed in patients with UC, CD, and healthy controls (HC), considering patient and disease characteristics as well as related serological markers. METHODS: TLR-4 Asp299Gly and TLR-4 Thr399Ile polymorphisms were determined in 187 UC and 163 CD patients and 274 randomly selected HC. C reactive protein, anti-Saccharomyces cerevisiae mannan antibodies, anti-mannobioside carbohydrate antibodies, anti-laminariobioside carbohydrate antibodies IgG, and anti-chitobioside carbohydrate antibodies (ACCA) IgA levels were also assessed. RESULTS: UC and especially pancolitis patients carried the mutant alleles more frequently compared to CD patients and HC or UC patients with different disease extents (P = 0.002 and P < 0.0001, respectively). Involvement of the colon was more frequent in CD patients with mutant TLR-4 compared to those with wild-type alleles (P = 0.004). Levels and positivity rates of ACCA IgA were lower in inflammatory bowel disease (IBD) patients carrying the mutant compared to those with wild-type alleles (0.075 < P < 0.05). Despite the mutant TLR-4 predisposition for UC pancolitis, smoking was associated with more limited disease (P < 0.001). CONCLUSIONS: The presence of TLR-4 Asp299Gly and TLR-4 Thr399Ile polymorphisms is related to UC pancolitis, involvement of the colon in CD, and lower ACCA IgA levels. Smoking reduces the extent of UC, even in the presence of mutant alleles.

Angiogenin, angiopoietin-1, angiopoietin-2, and endostatin serum levels in inflammatory bowel disease.

BACKGROUND: Angiogenesis is a complex process, involving a great number of mediators. It is implicated in the pathogenesis of numerous diseases, holding a critical role in inflammatory bowel disease (IBD). The objective of this study was to assess serum levels of angiogenin, angiopoietin-1, angiopoietin-2, and endostatin in IBD patients. METHODS: Measurement of all angiogenesis mediators was performed with a commercially available enzyme-linked immunosorbent assay. Fifty-two patients with ulcerative colitis (UC), 59 with Crohn's disease (CD), and 55 healthy controls (HC) were included in the study. The values were analyzed with regard to disease and patients characteristics. RESULTS: Angiogenin levels were significantly higher in IBD patients compared to HC (P < 0.001) and in UC and CD smoker patients compared to nonsmokers (P = 0.0121 and P = 0.005, respectively). Angiogenin levels were lower in UC patients receiving 5-aminosalicylate (5-ASA) alone, compared to those receiving combined therapy (P = 0.0478). Angiopoietin-1 levels were significantly lower in IBD patients compared to HC (P < 0.0001) and increased in smokers compared to nonsmoker UC patients (P = 0.0085). IBD patients demonstrated increased angiopoietin-2 levels compared to HC (P = 0.0131), while CD patients with disease restricted to the colon had significantly lower levels compared to other disease locations (P < 0.0001). Higher endostatin levels were recorded in UC patients with extensive colitis. CONCLUSIONS: Elevated serum angiogenin and angiopoietin-2 levels and lower serum angiopoietin-1 levels were shown in IBD patients, as well as a different pattern of angiogenic factor alterations related to location, treatment, smoking habits and gender.

Moderate performance of serum S100A12, in distinguishing inflammatory bowel disease from irritable bowel syndrome.

BACKGROUND: S100A12, a calcium-binding proinflammatory protein secreted by granulocytes, has been associated with different diseases of inflammatory origin, including inflammatory bowel disease (IBD). In this study, the utility of serum S100A12, in discriminating IBD from irritable bowel syndrome (IBS), was tested. METHODS: S100A12 serum levels were determined in 64 patients with ulcerative colitis (UC), 64 with Crohn's disease (CD) and 73 with IBS, by means of an enzyme-linked immunosorbent assay. S100A12 serum levels were evaluated with respect to the levels of known inflammatory markers and patients' characteristics. RESULTS: The median values of serum S100A12 levels were 68.2 ng/mL (range: 43.4-147.4) in UC, 70 ng/mL (41.4-169.8) in CD and 43.4 ng/mL (34.4-74.4) in IBS patients. UC and CD patients had significantly higher serum S100A12 levels compared to IBS patients (P = 0.001 for both comparisons). Moreover, a cut-off for serum S100A12 levels of 54.4 ng/mL could predict both UC and CD with a 66.7% sensitivity and a 64.4% specificity. The area under curve was estimated at 0.67 with a 95% confidence interval of 0.60-0.75 (P < 0.001). Considering standard activity indices, higher serum S100A12 levels in active compared to inactive IBD were observed, although the recorded difference did not reach statistical significance. C-reactive protein (CRP) and serum amyloid A (SAA) levels, showed a statistically significant positive correlation with S100A12 (r = 0.39, P = 0.001 and r = 0.23, P = 0.02 respectively). CONCLUSIONS: Increased levels of circulating S100A12 are found in IBD, compared to IBS. When used to distinguish IBD from IBS adult patients, serum S100A12 levels exhibit moderate performance. On the other hand, serum S100A12 may serve as an inflammatory marker in IBD, since it is well correlated with CRP and SAA.

Downregulation of serum epidermal growth factor in patients with inflammatory bowel disease. Is there a link with mucosal damage?

BACKGROUND: Epidermal growth factor (EGF) is a multipotent peptide which contributes to epithelial development, inhibition of gastric acid secretion, acceleration of wound healing, and promotion of angiogenesis. The aim of this study is to evaluate serum EGF concentrations in inflammatory bowel disease (IBD) patients, with regard to disease and patients' characteristics. METHODS: EGF determination was performed by a commercially available enzyme-linked immunosorbent assay. Fifty-two patients with ulcerative colitis (UC), 59 with Crohn's disease (CD), and 55 healthy controls (HC) were included in the study. RESULTS: Mean ( ± SEM) serum EGF levels were 217.2 ( ± 30.40) pg/mL in UC patients, 324.6 ( ± 37.29) pg/mL in CD patients, and 453.1 ( ± 39.44) pg/mL in HC. Serum EGF levels were significantly lower in UC and CD patients compared to HC (P < 0.0001 and P = 0.0199, respectively). Lower serum EGF levels were observed in UC compared to CD patients (P = 0.0277). Extent of the disease was found to affect serum EGF levels in UC, demonstrating significant reduction in patients with left-sided colitis and pancolitis in comparison with those with proctitis (P = 0.0190 and P = 0.0024, respectively). EGF concentration was not influenced by other characteristics of patients and disease. CONCLUSIONS: Significantly, lower levels of serum EGF are observed in IBD patients compared to HC, while disease extent plays a key role in regulation of serum EGF in UC. Downregulation of serum EGF may be correlated with different patterns of bowel inflammation, epithelial development, and wound healing in IBD.

Imbalance of tissue inhibitors of metalloproteinases (TIMP) - 1 and - 4 serum levels, in patients with inflammatory bowel disease.

BACKGROUND: Tissue inhibitors of metalloproteinases (TIMPs) play a key role in tissue degradation and remodeling. Since chronic inflammation is associated with tissue remodeling in inflammatory bowel disease (IBD), we evaluated serum TIMP-1 and TIMP-4 levels in IBD patients, in comparison with healthy controls (HC). METHODS: TIMP-1, TIMP-2 and TIMP-4 serum levels were determined in 53 patients with ulcerative colitis (UC), 52 patients with Crohn's disease (CD) and 50 HC, by means of commercially available enzyme-linked immunosorbent assays. The levels of TIMPs were evaluated with regard to the levels of inflammatory markers, such as C reactive protein (CRP) and serum amyloid A (SAA) and the clinical characteristics of patients, so that potential correlations could be recorded. RESULTS: Mean serum TIMP-1 levels were 414.9 +/- 17.6 ng/mL in UC patients, 446.1 +/- 22.8 ng/mL in CD patients and 296.5 +/- 20.6 ng/mL in HC. UC and CD patients had significantly higher serum TIMP-1 levels when compared to HC, (p < 0.0001 in both groups). Mean serum TIMP-1 levels were significantly higher in patients with active IBD (450.5 ng/mL) in comparison with patients with inactive disease (417.3 ng/mL, p = 0.03). Moreover, males showed significantly higher mean serum TIMP-1 levels (399.8 ng/mL), compared to females (368.5 ng/mL, p = 0.04). Mean serum TIMP-2 levels did not differ between UC and CD patients or HC (p > 0.05 in all cases). Mean serum TIMP-4 levels were 1761.2 +/- 67.7 pg/mL in UC patients, 1708.1 +/- 73.4 pg/mL in CD patients and 5573.4 +/- 1246.3 pg/mL in HC. UC and CD patients had significantly lower serum TIMP-4 levels when compared to HC (p = 0.008 and p = 0.02 respectively). Mean serum TIMP-4 levels were significantly lower in males (2772.9 pg/mL), compared to females (3299.0 pg/mL, p = 0.01). In addition, CRP levels showed a statistically significant correlation with TIMP-1 (r = 0.247, p = 0.01), and TIMP-4 levels (r = 0.217, p = 0.03). Similarly, there was a statistically significant correlation between SAA levels and both TIMP-1 (r = 0.264, p = 0.008) and TIMP-4 serum levels (r = 0.212, p = 0.03). CONCLUSION: An imbalance between TIMP-1 and TIMP-4 serum levels is present in IBD patients. TIMP-1 levels could be used not only for diagnostic purposes but also for the assessment of activity in IBD. Gender tends to influence TIMP-1 and TIMP-4 serum levels. These new findings bring into question the potential role of TIMPs in IBD, thus underlining the need for future studies which could offer new insight into this matter.