Mari Thörn

Independent patterns of cytochrome P450 gene expression in liver and blood in patients with suspected liver disease

Abstract. Objective: Assessment of liver metabolism using blood samples was tested by comparison of cytochrome P450 (CYP) gene expression in paired liver and blood samples from 13 individuals. Methods: Total RNA was isolated from percutaneous needle biopsies and blood collected simultaneously. Gene expression for CYP1A2, CYP1B1, CYP2E1 and CYP3A4 was studied using a real-time reverse-transcription polymerase chain reaction (RT-PCR) method. Results: All CYP mRNA species were expressed in all liver biopsies but at varying levels. The highest and lowest levels of expression were observed for CYP2E1 and CYP1B1, respectively. The expression patterns differed between blood and liver. CYP1B1 was expressed in all blood samples at a 20% higher level than in the liver. CYP1A2, CYP2E1 and CYP3A4 were expressed in blood at 35- to 5000-fold lower levels than in liver. None of the transcripts in blood showed any correlation with the expression in liver. Conclusion: We conclude that blood cannot serve as a surrogate organ for assessment of the expression of the studied CYP genes in liver.

Microscopic colitis in Uppsala health region, a population-based prospective study 2005–2009

Abstract Objective. The aim of this study is to report on the incidence of microscopic colitis (MC), any possible relation with inflammatory bowel disease (IBD), concomitant drug consumption, related diseases and the clinical course of the diseases. Methods. Both new cases of IBD and MC were registered at the same time in the same geographical area. The study started in the county of Uppsala 2005–2006, and other parts of the surrounding health region were included 2007–2009. Established morphological criteria were used, i.e. a layer of subepithelial collagen band ≥ 10 μm in collagenous colitis (CC) with concomitant inflammation and at least 20 lymphocytes per 100 epithelial cells in lymphocytic colitis (LC). Results. The authors found 272 new cases of MC, 154 with CC and 118 with LC. The mean age-adjusted incidence was 7.0/1,000,000 for CC and 4.8/100,000 for LC. The clinical course was dominated by single episodes with diarrhea or intermittent symptoms, but 14% suffered from chronic diarrhea. In 10% of the cases, diagnosis was made in individuals without chronic watery diarrhea. Although not systematically tested, concomitant celiac disease was found in approximately 5% of the patients. Conclusions. The incidence of MC in Uppsala health region is similar to other studied areas. The majority of patients had a self-limiting or easily treated condition, but 14% need a more or less continuous medication. Ten percent of the patients demonstrate other symptoms than chronic watery diarrhea. The possibility of concomitant celiac disease should be considered in new cases of MC.

Long-term effectiveness of vedolizumab in inflammatory bowel disease : a national study based on the Swedish National Quality Registry for Inflammatory Bowel Disease (SWIBREG)

Abstract Objectives: Clinical trials have demonstrated the efficacy of vedolizumab in inflammatory bowel disease (IBD). However, these findings may not reflect the clinical practice. Therefore, we aimed to describe a vedolizumab-treated patient population and assess long-term effectiveness. Materials and methods: Patients initiating vedolizumab between 1 June 2014 and 30 May 2015 were identified through the Swedish National Quality Registry for IBD. Prospectively collected data on treatment and disease activity were extracted. Clinical remission was defined as Patient Harvey Bradshaw index <5 in Crohn’s disease (CD) and Patient Simple Clinical Colitis Activity index <3 in ulcerative colitis (UC). Results: Two-hundred forty-six patients (147 CD, 92 UC and 7 IBD-Unclassified) were included. On study entry, 86% had failed TNF-antagonist and 48% of the CD patients had undergone ≥1 surgical resection. After a median follow-up of 17 (IQR: 14–20) months, 142 (58%) patients remained on vedolizumab. In total, 54% of the CD- and 64% of the UC patients were in clinical remission at the end of follow-up, with the clinical activity decreasing (p < .0001 in both groups). Faecal-calprotectin decreased in CD (p < .0001) and in UC (p = .001), whereas CRP decreased in CD (p = .002) but not in UC (p = .11). Previous anti-TNF exposure (adjusted HR: 4.03; 95% CI: 0.96–16.75) and elevated CRP at baseline (adjusted HR: 2.22; 95% CI: 1.10–4.35) seemed to be associated with discontinuation because of lack of response. Female sex was associated with termination because of intolerance (adjusted HR: 2.75; 95% CI: 1.16–6.48). Conclusion: Vedolizumab-treated patients represent a treatment-refractory group. A long-term effect can be achieved, even beyond 1 year of treatment.

Gene expression of cytochromes P450 in liver transplants over time

AbstractObjectiveThe aim of this study was to (a) quantify the gene expression of some cytochromes P450 (CYP), especially CYP3A4, in serial biopsies from liver grafts the first year after orthoptic liver transplantation (OLT) and (b) study the relationship between hepatic CYP3A4 gene expression and plasma levels of cyclosporine and tacrolimus.MethodsLiver tissue was obtained from surplus material of routine liver biopsies performed in 20 patients during the first year after OLT. Real-time reverse-transcription polymerase chain reaction was used for quantitative analyses of mRNA specific for CYP3A4, CYP3A5, CYP2E1 and CYP1A2 cytochromes as well as P-glycoprotein (P-gp). The gene expression of β-actin was used as an internal standard for comparisons between samples.ResultsThe median value of the mRNA for all cytochromes, but not for P-gp, was found to increase significantly over time. The gene expression of CYP3A5, CYP2E1 and CYP1A2 was higher than that of CYP3A4. The gene expression of CYP3A4 was related to the plasma concentration of cyclosporine and tacrolimus, i.e. low mRNA concentrations corresponded to high serum concentration levels and vice versa. The serum concentration of bilirubin or the prothrombin index did not correlate with the gene expression level of the cytochromes.ConclusionThe hepatic mRNA expression of CYP3A4 and the other investigated cytochromes increased during the first year after OLT. This was not the case with P-gp. Low CYP3A4 gene expression was related to high plasma levels of cyclosporine and tacrolimus and vice versa.

Long-term outcome of infliximab treatment in chronic active ulcerative colitis : a Swedish multicentre study of 250 patients

Real‐life long‐term data on infliximab treatment in ulcerative colitis are limited.

Quantitation of cytochrome P450 mRNAs in patients with suspected liver diseases as assessed by reverse transcriptase-polymerase chain reaction.

The cytochrome P450 system (CYP) is vital for the oxidation and detoxification of numerous drugs and other xenobiotics in the liver. Many of the CYP enzymes are polymorphically expressed and may be induced or inhibited by xenobiotics including drugs and alcohol. The measurement of gene expression is thus important in studies of the mechanisms of interaction with and function of the CYP system. We have developed a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method for the study of the mRNA expression of three CYP enzymes--2E1, 1A2, and 3A4--in snap-frozen percutaneous liver biopsy samples. The method was made quantitative by the introduction of a recombinant RNA internal standard that contains a transcript of the beta-globin gene and sequences specific for the studied CYP enzymes. The method allows the analysis of mRNA expression of several enzymes in as little as 5 mg of liver tissue. Liver tissue specimens from 19 patients with suspected liver disease were analyzed for CYP-specific mRNA expression. The mean mRNA concentrations for CYP1A2, 2E1, and 3A4 were 0.16, 0.74, and 0.32 amol of specific mRNA per nanogram of poly (A+) mRNA, respectively, but a large interindividual variation was observed. CYP3A7 primers were included in the internal standard. However, because of low expression it was not possible to quantitate the enzyme. This quantitative RT-PCR method is of value for studies of the mechanisms of variation and interactions with the members of the CYP enzyme family in healthy and diseased liver and other organs.

Clinical course of Crohn’s disease during the first 5 years. Results from a population-based cohort in Sweden (ICURE) diagnosed 2005–2009*

Abstract Objective: The aim of the study was to describe the medical treatment, change in phenotype, need for surgery and IBD-associated mortality during the first 5 years after diagnosis. Material and Methods: Patients diagnosed with Crohn’s disease including all age groups in the Uppsala healthcare region in the middle of Sweden 2005–2009 were included in the study. Medical notes were scrutinised and patients contacted. Out of 269 patients, 260 (96.3%) could be followed for 5 full years or until death. Results: The following drugs were used: 5-ASA 66.7%, systemic steroids 76.4%, antimetabolites 56.7% and anti-TNF 20.3%. Described with the Montreal classification, the proportion with inflammatory behaviour decreased from 78.1% to 74.0% from diagnosis to end of the observation, patients with stricturing behaviour increased from 13.0% to 15.4% and patients with penetrating behaviour increased from 8.9% to 10.6%. After the first year, 12.4% had been treated with intestinal resection or colectomy, a figure that increased to 14.8 after 5 years. Two patients suffered an IBD-related death. Conclusions: Compared to similar patient cohorts, the present study demonstrates that although the course of Crohn’s disease seems difficult to change during the first year after diagnosis, the following years up to 5 years shows a more benign course than has usually been described earlier.

Active cytomegalovirus infection diagnosed by real-time PCR in patients with inflammatory bowel disease: a prospective, controlled observational study*

Abstract Objective: It is assumed that cytomegaloviral (CMV) infection in inflammatory bowel disease (IBD) is caused by reactivation due to the immunosuppressive therapy, but the role of CMV as a pathophysiological factor and prognostic marker in IBD is unclear. The aim of this study was to investigate CMV infection in IBD, with real-time polymerase chain reaction (PCR) and immunohistochemistry, with emphasis on newly diagnosed disease. Materials and methods: In this prospective, controlled study, 67 patients with IBD and 34 control patients with irritable bowel syndrome (IBS) or rectal bleeding were included. Serology for CMV was analysed along with CMV DNA in plasma, mucosal biopsies, and faeces. Mucosal biopsies were further analysed with histopathology and CMV immunohistochemistry. Results: Detection of CMV IgM was more common in patients with IBD, compared to controls, 21% versus 3%. CMV DNA was found in 16% of patients with newly diagnosed, untreated IBD and in 38% of steroid-treated patients. Four of the five patients that needed urgent surgery were CMV-DNA positive in at least one of three sample types. None of the controls had detectable CMV DNA. Conclusions: Active CMV infection was found in high proportions of newly diagnosed untreated patients with IBD, in patients on immunosuppression and in patients in the need of surgery. Low CMV-DNA levels in non-immunosuppressed patients were not a risk factor for the development of more severe IBD, while the detection of CMV DNA in patients on immunosuppressive therapy may foresee disease progression.

Expression of cytochrome P450 and MDR1 in patients with proctitis

Background. The aim of this study was to investigate the effect of inflammation on the gene expression of three cytochrome P450s (CYP) and P-glycoprotein (P-gp) in the rectal and colonic mucosa in patients with proctitis. Methods. Biopsies were obtained from inflamed and normal mucosa in association with routine sigmoidoscopy in patients with proctitis. The biopsies were snap-frozen in liquid nitrogen. Real time PCR (polymerase chain reaction) was used for quantitative analyses of mRNA specific for the CYP2E1, CYP3A4 and CYP3A5 gene and the MDR1 genes. Values were normalised based on gene expression of β-actin to enable comparisons between samples. Results. The gene expression of CYP2E1 and CYP3A4 was lower in mucosa with severe inflammation vs normal mucosa (p<0.05). For CYP3A5 and P-gp there was no significant difference when comparing normal and inflammatory changed mucosa. Conclusion. Our study suggests that at least for some of the CYP enzymes the expression decreases in response to the inflammatory process in the gastrointestinal tract.

Low colectomy rate five years after diagnosis of ulcerative colitis. Results from a prospective population-based cohort in Sweden (ICURE) diagnosed during 2005–2009*

Abstract Objective: The medical treatment of ulcerative colitis (UC) has seen a change towards a more active attitude during recent years, including both the use of more traditional drugs as well as new biological substances. In this epidemiological study we have evaluated the results of modern treatment of UC in a population-based cohort of patients including all age groups, with regard to relapse rate, colectomy and IBD-associated mortality. Material and methods: Patients diagnosed with UC in the Uppsala health care region in the middle of Sweden during 2005–2009 were included in the study. Out of 524 patients, 491 (93%) could be followed for five full years or until death. Results: Nineteen patients (3.9%) had died and two of these deaths could be attributed to UC (one postoperative death and one colonic carcinoma). The following drugs were used by the patients during the study period: 5-ASA (91%), systemic steroids (66%), immunomodulators (IMM), mainly thiopurines (26%) and anti-TNF (11%). During the observation period, 74% experienced at least one relapse and 5.3% were subjected to colectomy. Among patients <17 years at diagnosis, colectomy was performed in two (4.8%). Conclusions: Five years after diagnosis of ulcerative colitis, 5.3% had been subjected to colectomy and two patients (0.38%) had died because of the disease.