Zonulin upregulation is associated with increased gut permeability in subjects with type 1 diabetes and their relatives.

Zonulin, a protein that modulates intestinal permeability, is upregulated in several autoimmune diseases and is involved in the pathogenesis of autoimmune diabetes in the BB/Wor animal model of the disease. To verify the association between serum zonulin levels and in vivo intestinal permeability in patients with type 1 diabetes, both parameters were investigated in different stages of the autoimmune process. Forty-two percent (141 of 339) of the patients had abnormal serum zonulin levels, as compared with age-matched control subjects. The increased zonulin levels correlated with increased intestinal permeability in vivo and changes in claudin-1, claudin-2, and myosin IXB genes expression, while no changes were detected in ZO1 and occludin genes expression. When tested in serum samples collected during the pre-type 1 diabetes phase, elevated serum zonulin was detected in 70% of subjects and preceded by 3.5 +/- 0.9 years the onset of the disease in those patients who went on to develop type 1 diabetes. Combined, these results suggest that zonulin upregulation is associated with increased intestinal permeability in a subgroup of type 1 diabetic patients. Zonulin upregulation seems to precede the onset of the disease, providing a possible link between increased intestinal permeability, environmental exposure to non-self antigens, and the development of autoimmunity in genetically susceptible individuals.

Worse clinical course of disease in Crohn's patients with previous appendectomy.

OBJECTIVES: The aim of the present study was to assess the effect of previous appendectomy in a series of Crohn's disease (CD) patients on the clinical characteristics and course of disease. METHODS: Demographic and clinical data were retrospectively analysed for 129 consecutive outpatients (68 men and 61 women, median age 38 years) with CD. For each patient, information concerning appendectomy, indication for surgery (acute/chronic) and the date of surgery were recorded. The date of the appendectomy in relation to the date of CD diagnosis was carefully assessed in order to evaluate the precise relationship between the two events. A total of 129 CD patients who had not undergone previous appendectomy served as controls. The severity of disease was assessed retrospectively by evaluating the need for systemic steroids, immunosuppressants and surgical treatment for CD, particularly resective procedures. RESULTS: Forty-one CD patients (31.8%) underwent appendectomy before the diagnosis of disease. Appendectomy before diagnosis showed a negative association with colonic disease localization and with articular manifestations. In addition, the 41 patients with previous appendectomy had a significantly greater risk of surgery, particularly resective. Multivariate analysis confirmed appendectomy performed before diagnosis as an independent risk factor for surgery; on the contrary, colonic site and inflammatory type of disease were independent factors protecting against surgery. Although current smokers were at an increased risk of surgical treatment, a smoking habit alone did not seem to be relevant at the multivariate analysis. CONCLUSION: The results of this study indicate a worse clinical course of CD in patients appendicectomized before diagnosis.

Serum p53 antibodies in patients affected with ulcerative colitis.

During tumor progression, the accumulation in genetic alterations is a fundamental characteristic of malignant cells. p53 gene is frequently mutated in human tumor. Cellular accumulation of p53 protein can initiate an immune response with generation of circulating anti-p53 antibodies. Patients with ulcerative colitis have an increased risk of developing colorectal neoplasm and, among the different genes involved in carcinogenesis, p53 may play a key role. Sera and tissues from 97 patients (M = 53, F = 44) affected with ulcerative colitis (UC) were collected. Serum anti-p53 antibodies (p53Abs) were detected in duplicate with ELISA method. Serum p53Abs were detectable in 9.3% (9/97) of patients affected with UC. In these patients, the titer of p53Ab ranged between 3.1 and 14.9 U/mL (mean, 6.6 U/mL; SD, 4.64). Serum p53Abs were undetectable in control group. With an immunoluminometric assay for the quantitative determination of p53, we found 9/97 positive samples (> or = 0.69 mg/mg of total proteins). In contrast, the samples of the remaining 89 patients were found negative (< or = 0.30 mg/mg of total proteins). All patients that were positive for anti-p53 antibodies were also positive with p53 protein accumulation in the tissue of colonic biopsies. In UC, follow-up with colonoscopy has several advantages. The colonoscopy is not well accepted by patients, and poor patient observance has the potential to seriously devalue the technique as a screening tool, despite practical considerations of competence within endoscopy service. Serological detection of p53Abs by enzyme-linked immunosorbent assay (ELISA) is easy to perform, does not require tumor specimen, can be performed in a routine diagnostic procedure, may be used in clinical practice, and could facilitate physicians in patient monitoring. We suggest that serum p53Abs assessment, indirect marker for p53 gene mutations, and abnormally high p53 protein levels could be considered to have a potential for use as a complementary test to improve surveillance program performance.

Assessment of intestinal permeability and orocecal transit time in patients with systemic sclerosis: analysis of relationships with epidemiologic and clinical parameters.

OBJECTIVE: The aim of this study was to assess intestinal permeability (IP) in patients with systemic sclerosis (SSc) and to relate the results with general disease activity and gastrointestinal involvement. METHODS: Twenty-eight females and four males were studied. Patients with severe gastrointestinal involvement were excluded. Thirty-three healthy volunteers served as controls. Intestinal permeability was assessed by means of the orally administered cellobiose/mannitol sugar (Ce/Ma) test. Intestinal transit time (ITT) was investigated with the H2-lactulose breath test. RESULTS: The mean value of IP in 32 SSc patients was significantly higher than in 33 controls ( P<0.05), although it fell within the normal range. Eleven patients showed abnormally high individual IP values (>0.028) that significantly correlated to disease duration ( r=0.73). Altered IP was associated with the higher but not statistically relevant presence of anti-Scl70 antibodies (9/11) and to more severe gastrointestinal involvement. More than half of the SSc patients showed slower orocecal transit times on the H2 breath test. In particular, delayed ITT was observed in 60% of patients with increased IP and in all patients with moderate gastrointestinal involvement according to the scleroderma severity scale. CONCLUSION: Intestinal permeability was altered in 11/32 SSc patients. Correlations between increased IP and duration of disease and degree of gastrointestinal involvement appear to support the hypothesis of secondary involvement of the intestinal barrier, and the presence of anti-Scl70 antibodies in 82% of the patients with higher IP clearly reinforces the hypothesis of an altered immune response in these subjects.

Cellobiose and lactulose coupled with mannitol and determined using ion-exchange chromatography with pulsed amperometric detection, are reliable probes for investigation of intestinal permeability.

Lactulose/mannitol and cellobiose/mannitol tests are currently used in the investigation of intestinal permeability (IP) in many gastrointestinal diseases. The aim of this study was to produce a good technique for the determination and comparison of the above-mentioned sugar probes to overcome the problem caused by the presence of significant glycosuria in patients affected by particular metabolic disorders such as diabetes mellitus. Tests were performed in 25 healthy volunteers, using either cellobiose (Ce) (5 g) and mannitol (Ma) (2 g), or lactulose (La) (5 g) and mannitol (2 g), given as oral isosmolar loads. Sugars were recovered in urine collected for 5 h. Analysis was carried out by using anion-exchange chromatography (AEC) with pulsed amperometric detection (PAD). Baseline separation of the above carbohydrates was achieved within 13 min by using a Carbopac PA-100 column and linear gradient elution. Carbohydrate quantification was performed by an internal standard method. The calibration curve for each sugar is linear to 40 mM. The limit of sugar detection is 0.01 mM. Recovery of sugar probes is between 98.2 and 100%. The %La, %Ce, %Ma in urine were evaluated and their ratios (Ce/Ma and La/Ma) were calculated. No significant difference in IP parameters were shown (La/Ma to Ce/Ma 0.018+/-0.014 vs. 0.012+/-0.007; the attendant probability of the null hypothesis being P=0.0714). Ce/Ma and/or La/Ma tests result similarly reliable in the clinical investigation of IP and the described new method is also helpful in urine even with high glucose concentration, without any interference.