Changes in matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinases (TIMP) expression profile in Crohn's disease after immunosuppressive treatment correlate with histological score and calprotectin values

Matrix metalloproteinases in intestinal fibrosis

Intestinal fibrosis is a common complication in patients with inflammatory bowel disease [IBD], in particular Crohn's disease [CD]. Unfortunately, at present intestinal fibrosis is not yet preventable, and cannot be treated by interventions other than surgical removal. Intestinal fibrosis is characterized by excessive accumulation of extracellular matrix [ECM], which is caused by activated fibroblasts and smooth muscle cells. Accumulation of ECM results from an imbalanced production and degradation of ECM. ECM degradation is mainly performed by matrix metalloproteinases [MMPs], enzymes that are counteracted by tissue inhibitors of MMPs [TIMPs]. In IBD patients, MMP activity [together with other protease activities] is increased. At the same time, CD patients have a generally lower MMP activity compared to ulcerative colitis patients, who usually do not develop intestinal strictures or fibrosis. The exact regulation and role[s] of these MMPs in fibrosis are far from understood. Here, we review the current literature about ECM remodelling by MMPs in intestinal fibrosis and their potential role as biomarkers for disease progression or druggable targets.

Anti-Inflammatory Effects of Dietary Polyphenols through Inhibitory Activity against Metalloproteinases

Matrix metalloproteinases (MMPs) are zinc-dependent metalloproteinases that play important roles in a variety of diseases, including cancer, cardiovascular disease, diabetes, obesity, and brain diseases. Dietary polyphenols are thought to have a variety of beneficial effects on these diseases characterized by inflammation. Clinical studies have demonstrated that MMPs are in most cases upregulated in various inflammatory diseases, including osteoarthritis, rheumatoid arthritis, inflammatory bowel disease, and Alzheimer's disease. Studies using patient-derived human samples, animal studies, and cellular experiments have suggested that polyphenols may be beneficial against inflammatory diseases by suppressing MMP gene expression and enzyme activity. One important mechanism by which polyphenols exert their activity is the downregulation of reactive oxygen species that promote MMP expression. Another important mechanism is the direct binding of polyphenols to MMPs and their inhibition of enzyme activity. Molecular docking analyses have provided a structural basis for the interaction between polyphenols and MMPs and will help to explore new polyphenol-based drugs with anti-inflammatory properties.

Altered Bioavailability and Pharmacokinetics in Crohn's Disease: Capturing Systems Parameters for PBPK to Assist with Predicting the Fate of Orally Administered Drugs

Backgrond and Objective

Crohn’s disease (CD) is a chronic inflammatory bowel disease that affects a wide age range. Hence, CD patients receive a variety of drugs over their life beyond those used for CD itself. The changes to the integrity of the intestine and its drug metabolising enzymes and transporters (DMETs) can alter the oral bioavailability of drugs. However, there are other changes in systems parameters determining the fate of drugs in CD, and understanding these is essential for dose adjustment in patients with CD.

Methods

The current analysis gathered all the available clinical data on the kinetics of drugs in CD (by March 2021), focusing on orally administered small molecule drugs. A meta-analysis of the systems parameters affecting oral drug pharmacokinetics was conducted. The systems information gathered on intestine, liver and blood proteins and other physiological parameters was incorporated into a physiologically based pharmacokinetic (PBPK) platform to create a virtual population of CD patients, with a view for guiding dose adjustment in the absence of clinical data in CD.

Results

There were no uniform trends in the reported changes in reported oral bioavailability. The nature of the drug as well as the formulation affected the direction and magnitude of variation in kinetics in CD patients relative to healthy volunteers. Even for the same drug, the reported changes in exposure varied, possibly due to a lack of distinction between the activity states of CD. The highest alteration was seen with S-verapamil and midazolam, 8.7- and 5.3-fold greater exposure, respectively, in active CD patients relative to healthy volunteers. Only one report was available on liver DMETs in CD, and indicated reduced CYP3A4 activity. In a number of reports, mRNA expression of DMETs in the ileum and colon of CD patients was measured, focussing on P-glycoprotein (p-gp) transporter and CYP3A4 enzyme, and showed contradictory results. No data were available on protein expression in duodenum and jejunum despite their dominant role in oral drug absorption.

Conclusion

There are currently inadequate dedicated clinical or quantitative proteomic studies in CD to enable predictive PBPK models with high confidence and adequate verification. The PBPK models for CD with the available systems parameters were able to capture the major physiological influencers and the gaps to be filled by future research. Quantification of DMETs in the intestine and the liver in CD is warranted, alongside well-defined clinical drug disposition studies with a number of index drugs as biomarkers of changes in DMETs in these patients, to avoid large-scale dedicated studies for every drug to determine the effects of disease on the drug’s metabolism and disposition and the consequential safety and therapeutic concerns.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-022-01169-4.

Mucosal Gene Transcript Signatures in Treatment Naïve Inflammatory Bowel Disease: A Comparative Analysis of Disease to Symptomatic and Healthy Controls in the European IBD-Character Cohort

Background

Studies of the mucosal transcriptomic landscape have given new insight into the pathogenesis of inflammatory bowel disease (IBD). Recently, the predictive biomarker potential of gene expression signatures has been explored. To further investigate the mucosal gene expression in IBD, we recruited a cohort of treatment naïve patients and compared them to both symptomatic and healthy controls.

Methods

Altogether, 323 subjects were included: Crohn’s disease (N = 75), ulcerative colitis (N = 87) and IBD unclassified (N = 3). Additionally, there were two control groups: symptomatic controls (N = 131) and healthy controls (N = 27). Mucosal biopsies were collected during ileocolonoscopy and gene expression in inflamed and non-inflamed mucosa was explored. Gene expression profiling was performed using Agilent G3 Human Gene Expression 860K v3 One-Color microarray. We recorded information about treatment escalation to anti-TNF agents or surgery, and anti-TNF response, to explore predictive opportunities of the mucosal transcriptome.

Results

Gene expression profiles in symptomatic controls in whom IBD had been excluded resembled that of IBD patients and diverged from that of healthy controls. In non-inflamed Crohn’s disease and ulcerative colitis, gene set enrichment analysis revealed dysregulation of pathways involved in basic cellular biological processes. Mitochondria-associated pathways were dysregulated both in non-inflamed and inflamed Crohn’s disease and ulcerative colitis (>2.6 normalized enrichment scores <−1.8). Gene expression signatures of Crohn’s disease and ulcerative colitis did not predict time for treatment escalation (p = 0.175). No significant association was found between gene expression signatures and anti-TNF response.

Conclusion

Non-inflamed samples are probably superior to inflamed samples when exploring gene expression signatures in IBD and might reveal underlying mechanisms central for disease initiation. The gene expression signatures of the control groups were related to if they were symptomatic or not, which may have important implications for future study designs.

The Role of Extracellular Matrix Components in Inflammatory Bowel Diseases

The remodeling of extracellular matrix (ECM) within the intestine tissues, which simultaneously involves an increased degradation of ECM components and excessive intestinal fibrosis, is a defining trait of the progression of inflammatory bowel diseases (IBDs), which include ulcerative colitis (UC) and Crohn's disease (CD). The increased activity of proteases, especially matrix metalloproteinases (MMPs), leads to excessive degradation of the extracellular matrix and the release of protein and glycoprotein fragments, previously joined with the extracellular matrix, into the circulation. MMPs participate in regulating the functions of the epithelial barrier, the immunological response, and the process of wound healing or intestinal fibrosis. At a later stage of fibrosis during IBD, excessive formation and deposition of the matrix is observed. To assess changes in the extracellular matrix, quantitative measurement of the concentration in the blood of markers dependent on the activity of proteases, involved in the breakdown of extracellular matrix proteins as well as markers indicating the formation of a new ECM, has recently been proposed. This paper describes attempts to use the quantification of ECM components as markers to predict intestinal fibrosis and evaluate the healing process of the gut. The markers which reflect increased ECM degradation, together with the ones which show the process of creating a new matrix during IBD, allow the attainment of important information regarding the changes in the intestinal tissue, epithelial integrity and extracellular matrix remodeling. This paper contains evidence confirming that ECM remodeling is an integral part of directional cell signaling in the progression of IBD, and not only a basis for the ongoing processes.

Thalidomide Prevented and Ameliorated Pathogenesis of Crohn's Disease in Mice via Regulation of Inflammatory Response and Fibrosis

Crohn's disease (CD) is a chronic, relapsing form of inflammatory bowel disease, seriously threatening human health. Thalidomide has been used for the treatment of CD. However, the effects and the possible mechanisms of thalidomide on CD are still unclear. Herein, our study demonstrated that thalidomide protected colon mucosa against trinitro-benzene-sulfonic acid (TNBS)-induced injury, diminished inflammatory infiltration and levels of IFN-γ, IGF-1, IL-6, IL-17, TNF-α, while increased the levels of IL-10 and TGF-γ. Moreover, it reversed the intestinal fibrosis and inhibited the accumulated infiltration, down-regulated the expression of col1a2, col3a2, MMP-3, MMP-9, MMP-1, TGF-γ, α-SMA, but up-regulated the expression of TIMP-1 and Vimentin. Although it could be observed that the effect of thalidomide administration in modeling was better than after modeling, there was no statistical difference between the two groups. The present study provided evidence that the therapeutic effect of thalidomide alleviated the inflammatory response and damage of colon tissue, mainly by restoring the imbalance of TH17/Treg cells and inhibiting intestinal fibrosis in TNBS-induced mice colitis.

Reduction in TIMP-2 serum levels predicts remission of inflammatory bowel diseases

BACKGROUND

Growing evidence indicates tissue inhibitors of matrix metalloproteinases (TIMPs) as potential players in inflammatory bowel disease (IBD), but, no prospective data are available in IBD remission/relapse.

MATERIAL & METHODS

In this prospective pilot study, a cohort of IBD patients (n = 32) was enrolled and treated with monoclonal anti-TNF-α antibodies. Patients were clinically followed up for a median period of 54 weeks. Serum circulating levels of C-reactive protein (CRP), TIMP-1 and -2, matrix metalloproteinase (MMP)-9 and -8, myeloperoxidase (MPO) and neutrophil elastase (NE) were assessed by ELISA at enrolment and at the end of the treatment.

RESULTS

The percentage (%) TIMP-2 reduction from baseline to end of treatment was independently associated with IBD remission at the end of treatment and follow-up as well. ROC curve analysis further confirmed the good prognostic accuracy of % TIMP-2 reduction over the treatment period. Conversely, no other change in inflammatory molecule concentrations was able to predict short- or long-term IBD remission.

CONCLUSIONS

This study indicates TIMP-2 reduction during IBD treatment with monoclonal anti-TNF-α antibodies as a potential prognostic parameter of short and long term remission. To understand if TIMP-2 is an innocent biomarker or an active pathophysiological factor in IBD remains to be clarified.

Fecal Matrix Metalloprotease-9 and Lipocalin-2 as Biomarkers in Detecting Endoscopic Activity in Patients With Inflammatory Bowel Diseases

BACKGROUND

Fecal biomarkers are emerging tools in the assessment of mucosal healing in inflammatory bowel diseases (IBD).

GOALS

We aimed to evaluate the accuracy of fecal matrix metalloprotease-9 (MMP-9) and fecal lipocalin-2 (LCN-2) compared with calprotectin in detecting endoscopic activity in IBD STUDY:: Overall, 86 IBD adults underwent colonoscopy consecutively and prospectively, with Crohn's disease Endoscopic Index of Severity (CDEIS) in Crohn's disease (CD) patients or Mayo endoscopic subscore calculation for ulcerative colitis (UC) patients, and stool collection. Fecal calprotectin was measured using quantitative immunochromatographic testing. Fecal MMP-9 and LCN-2 was quantified by enzyme-linked immunosorbent assay. MMP-9 and LCN-2 thresholds were determined using receiver operating curves.

RESULTS

In 54 CD patients, fecal calprotectin, MMP-9 and LCN-2 correlated with CDEIS and were significantly increased in patients with endoscopic ulcerations. MMP-9 >350 ng/g detected endoscopic ulceration in CD with a sensitivity of 90.0% and a specificity of 63.6%, compared with fecal calprotectin >250 μg/g (sensitivity=90.5% and specificity=59.1%). Fecal LCN-2 demonstrated lower performances than the 2 other biomarkers (sensitivity=85.7% and specificity=45.5%).In 32 UC patients, fecal MMP-9, LCN-2, and calprotectin levels were significantly increased in patients with endoscopic activity. In UC patients, fecal MMP-9 >900 ng/g had the best efficacy to detect endoscopic activity (sensitivity=91.0% and specificity=80.0%, compared with fecal calprotectin >250 μg/g (sensitivity=86.4% and specificity=80.0%) and LCN-2 >6700 ng/g (sensitivity=82.0% and specificity=80.0%).

CONCLUSIONS

Fecal MMP-9 is a reliable biomarker in detecting endoscopic activity in both UC and CD patients.

Identification of matrix metalloproteinase-2 and -9 activities within the intestinal mucosa of dogs with chronic enteropathies

BACKGROUND

Matrix metalloproteinases (MMPs) 2 and 9 are zinc- and calcium-dependent endopeptidases involved in the breakdown and reconstitution of extracellular matrix under both physiological and pathological conditions. Mucosal MMP-2 and -9 activities have been reported to be upregulated in the intestine of humans with inflammatory bowel disease (IBD), and in animal models of IBD. However, their involvement in the pathogenesis of canine chronic enteropathies (CE) is unknown. This study investigated mucosal pro- and active MMP-2 and -9 activities in dogs with CE and healthy dogs using gelatin zymography, and also to determine the association of their activities in dogs with CE with the canine IBD activity index (CIBDAI), histopathologic findings, the clinical outcome, and hypoalbuminemia. Intestinal mucosal samples from duodenum, ileum, colon, and cecum were collected from 40 dogs with CE and 18 healthy Beagle dogs.

RESULTS

In dogs with CE, the number of samples positive for mucosal pro- and active MMP-2 was significantly higher in the duodenum (P < 0.0001 and P = 0.011, respectively), ileum (P = 0.002 and P = 0.018, respectively), and colon (P < 0.0001 and P = 0.002, respectively), compared with healthy controls. Mucosal pro-MMP-9-positive samples in the duodenum and colon were significantly more frequent in dogs with CE than in healthy dogs (P = 0.0004 and P = 0.001, respectively). Despite the presence of mucosal samples positive for active MMP-9 in the intestinal segments of dogs with CE, the difference compared to healthy controls did not reach statistical significance. None of the intestinal mucosal samples in healthy dogs showed gelatinolytic activity corresponding to the control bands of active MMP-2 and -9. Mucosal active MMP-9 activities displayed a significant positive association with the severity of neutrophil infiltration in the duodenum (P = 00.040), eosinophils in the cecum (P = 00.037), and the CIBDAI score for ileum samples (P = 0.023). There was no significant association of pro- and active MMP-2 and -9 levels with the clinical outcome or hypoalbuminemia.

CONCLUSIONS

This study is the first to demonstrate upregulation of mucosal pro- and active MMP-2 and pro-MMP-9 in the intestine of dogs with CE compared to healthy dogs. The results provide supporting evidence for the possible involvement of MMP-2 and -9 in the pathogenesis of canine CE.

Pathobiology of neutrophil-epithelial interactions

Polymorphonuclear neutrophils (PMNs) are innate immune system cells that play an essential role in eradicating invading pathogens. PMN migration to sites of infection/inflammation requires exiting the microcirculation and subsequent crossing of epithelial barriers in mucosa-lined organs such as the lungs and intestines. Although these processes usually occur without significant damage to surrounding host tissues, dysregulated/excessive PMN transmigration and resultant bystander-tissue damage are characteristic of numerous mucosal inflammatory disorders. Mechanisms controlling PMN extravasation have been well characterized, but the molecular details regarding regulation of PMN migration across mucosal epithelia are poorly understood. Given that PMN migration across mucosal epithelia is strongly correlated with disease symptoms in many inflammatory mucosal disorders, enhanced understanding of the mechanisms regulating PMN transepithelial migration should provide insights into clinically relevant tissue-targeted therapies aimed at ameliorating PMN-mediated bystander-tissue damage. This review will highlight current understanding of the molecular interactions between PMNs and mucosal epithelia and the associated functional consequences.

Andrographolide Inhibits Proliferation and Metastasis of SGC7901 Gastric Cancer Cells

To explore the mechanisms by which andrographolide inhibits gastric cancer cell proliferation and metastasis, we employed the gastric cell line SGC7901 to investigate the anticancer effects of andrographolide. The cell survival ratio, cell migration and invasion, cell cycle, apoptosis, and matrix metalloproteinase activity were assessed. Moreover, western blotting and real-time PCR were used to examine the protein expression levels and the mRNA expression levels, respectively. The survival ratio of cells decreased with an increasing concentration of andrographolide in a dose-dependent manner. Consistent results were also obtained using an apoptosis assay, as detected by flow cytometry. The cell cycle was blocked at the G2/M2 phase by andrographolide treatment, and the proportion of cells arrested at G1/M was enhanced as the dose increased. Similarly, wound healing and Transwell assays showed reduced migration and invasion of the gastric cancer cells at various concentrations of andrographolide. Andrographolide can inhibit cell proliferation, invasion, and migration, block the cell cycle, and promote apoptosis in SGC7901 cells. The mechanisms may include upregulated expression of Timp-1/2, cyclin B1, p-Cdc2, Bax, and Bik and downregulated expression of MMP-2/9 and antiapoptosis protein Bcl-2.

Pirfenidone inhibits the proliferation of fibroblasts from patients with active Crohn's disease

OBJECTIVE

One-third of Crohn's disease (CD) patients develop intestinal strictures that require repeated surgical intervention. Current anti-inflammatory therapies have limited effect on stricture development, which necessitates the exploration of new pharmacological approaches. Pirfenidone (PFD), a novel anti-fibrotic agent, was recently approved in Europe for the treatment of idiopathic pulmonary fibrosis (IPF). We hypothesized that observations in IPF could be transferable to intestinal fibrosis and that PFD inhibits the proliferation and extracellular matrix (ECM) turnover of gut-derived fibroblasts from CD patients.

MATERIAL AND METHODS

Fibroblasts were isolated from biopsies of inflamed (n = 8) and non-inflamed (n = 5) colonic mucosa. Expression of CD90 and alpha-smooth muscle actin (αSMA) expression was determined by flow cytometry. The fibroblasts were cultured with PFD (0.5, 1.0 and 2.0 mg/ml). Proliferation was evaluated with CellTiter 96(®) AQueous One Solution Cell Proliferation Assay. Production of matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinases-1 (TIMP-1) and collagen were assessed using ELISA and calorimetric assays, respectively.

RESULTS

The majority of the fibroblasts were αSMA-positive myofibroblasts. PFD inhibited fibroblast proliferation [0.94 (PFD 0.5 mg/ml); 0.76 (1.0 mg/ml); 0.58 (2.0 mg/ml)] and production of MMP-3 [0.85 (0.5 mg/ml); 0.74 (1.0 mg/ml); 0.63 (2.0 mg/ml)] dose-dependently (both p = 0.0001). The anti-proliferative effect of PFD was reversible (p = 0.0001), indicating that PFD does not act by an irreversible cytotoxic mechanism. PFD did not influence neither TIMP-1 nor collagen production.

CONCLUSION

PFD inhibited the proliferation and the production of MMP-3 dose-dependently in gut-derived fibroblast from CD patients. Our observations support further studies on PFD in stricturing CD.

Update on pathogenesis and predictors of response of therapeutic strategies used in inflammatory bowel disease

The search for biomarkers that characterize specific aspects of inflammatory bowel disease (IBD), has received substantial interest in the past years and is moving forward rapidly with the help of modern technologies. Nevertheless, there is a direct demand to identify adequate biomarkers for predicting and evaluating therapeutic response to different therapies. In this subset, pharmacogenetics deserves more attention as part of the endeavor to provide personalized medicine. The ultimate goal in this area is the adjustment of medication for a patient’s specific genetic background and thereby to improve drug efficacy and safety rates. The aim of the following review is to utilize the latest knowledge on immunopathogenesis of IBD and update the findings on the field of Immunology and Genetics, to evaluate the response to the different therapies. In the present article, more than 400 publications were reviewed but finally 287 included based on design, reproducibility (or expectancy to be reproducible and translationable into humans) or already measured in humans. A few tests have shown clinical applicability. Other, i.e., genetic associations for the different therapies in IBD have not yet shown consistent or robust results. In the close future it is anticipated that this, cellular and genetic material, as well as the determination of biomarkers will be implemented in an integrated molecular diagnostic and prognostic approach to manage IBD patients.

Matrix metalloproteinases in inflammatory bowel disease: an update

Matrix metalloproteinases (MMPs) are known to be upregulated in inflammatory bowel disease (IBD) and other inflammatory conditions, but while their involvement is clear, their role in many settings has yet to be determined. Studies of the involvement of MMPs in IBD since 2006 have revealed an array of immune and stromal cells which release the proteases in response to inflammatory cytokines and growth factors. Through digestion of the extracellular matrix and cleavage of bioactive proteins, a huge diversity of roles have been revealed for the MMPs in IBD, where they have been shown to regulate epithelial barrier function, immune response, angiogenesis, fibrosis, and wound healing. For this reason, MMPs have been recognised as potential biomarkers for disease activity in IBD and inhibition remains a huge area of interest. This review describes new roles of MMPs in the pathophysiology of IBD and suggests future directions for the development of treatment strategies in this condition.

Identification of matrix metalloproteinase-2 and -9 activities within intestinal mucosa of clinically healthy beagle dogs

Matrix metalloproteinases (MMPs) 2 and 9 are zinc-dependent endopeptidases that contribute to the control of breakdown and reconstitution of extracellular matrix under both normal and pathological conditions. The main objective of this study was to identify the presence of MMP-2 and -9 in the mucosa of the small and large intestines of clinically healthy beagle dogs using gelatin zymography technique. Intestinal mucosa samples from four different parts of the intestine (duodenum, jejunum, ileum and colon) were taken from 12 healthy laboratory beagle dogs and examined histologically. Based on WSAVA histology standards, recorded findings of all samples were considered insignificant. Pro-MMP-2 and -9 activities were found in 17/48 (35%) and 25/48 (52%) of the samples, respectively. Among four different parts of the intestine of 12 dogs, the ileum had the highest positivity rates of 7/12 (58.3%) and 8/12 (66.7%) for pro-MMP-2 and -9 activities, respectively. However, statistical analysis showed no significant difference of pro-MMP-2 and -9 activities between the separate parts of the intestine (P>0.05). None of the intestinal samples showed gelatinolytic activity corresponding to the control bands of active MMP-2 and MMP-9. This study showed that pro-MMP-2 and -9 could be detected in the intestinal mucosa of healthy dogs using zymography, which seems to be a useful tool to evaluate the role of MMP-2 and -9 in the pathogenesis of canine chronic enteropathies, including inflammatory bowel diseases.

Mechanisms that mediate the development of fibrosis in patients with Crohn's disease

Crohn's disease is complicated by the development of fibrosis and stricture in approximately 30% to 50% of patients over time. The pathogenesis of fibrostenotic disease is multifactorial involving the activation of mesenchymal cells by cytokines, growth factors, and other mediators released by immune cells, epithelial cells, and mesenchymal cells. Transforming growth factor β, a key activator of mesenchymal cells, is central to the process of fibrosis and regulates numerous genes involved in the disordered wound healing including collagens, and other extracellular matrix proteins, connective tissue growth factor, and insulin-like growth factors. The activated mesenchymal compartment is expanded by recruitment of new mesenchymal cells through epithelial to mesenchymal transition, endothelial to mesenchymal transition, and invasion of circulating fibrocytes. Cellular hyperplasia and increased extracellular matrix production, particularly collagens, from fibroblasts, myofibroblasts, and smooth muscle cells add to the disturbed architecture and scarring on the intestine. Extracellular matrix homeostasis is further disrupted by alterations in the expression of matrix metalloproteinases and tissue inhibitors of metalloproteinase in the gut. Among the 163 susceptibility genes identified that contribute to susceptibility in inflammatory bowel disease mutations in NOD2/CARD15, innate immune system components and autophagy jointly contribute to the activation of mesenchymal cells and pathogenesis of fibrosis in this polygenic disorder. Numerous growth factors cytokines and other mediators also contribute to development of fibrosis in the susceptible patient. This review focuses on the molecular mechanisms that regulate mesenchymal cell function, particularly smooth muscle cells, the largest compartment of mesenchyme in the intestine, that lead to fibrosis in Crohn's disease.

Fecal calprotectin, MMP-9, and human beta-defensin-2 levels in pediatric inflammatory bowel disease

PURPOSE

Fecal MMP-9 and human beta-defensin-2 (HBD-2)levels, potential markers of intestinal inflammation, are in sufficiently explored in pediatric inflammatory bowel disease(IBD). The aim was to study fecal MMP-9 and HBD-2 in pediatric IBD to compare their performance to calprotectin and to study whether they would provide additional value in categorizing patients according to their disease subtype.

METHODS

Fecal calprotectin, MMP-9, and HBD-2 levels were measured with ELISA in 110 pediatric patients with IBD(Crohn’s disease, n = 68; ulcerative colitis (UC), n = 27; unclassified, n = 15; median age, 14). To compare the performance of the fecal markers, the area under the receiver operating characteristics curve (±95 % CI) was used. In addition,the best cut-off values of each measure to differentiate IBD patients and controls (n = 27 presenting with diarrhea, abdominal pain, and/or anemia) were derived by maximizing sensitivity and specificity.

RESULTS

Of the fecal markers studied, calprotectin performed best for separation of IBD and non-IBD patients with the are a under curve (AUC) of 0.944 (95 % CI, 0.907 to 0.981). For MMP-9, AUC was 0.837 (95% CI, 0.766 to 0.909), the levels being significantly higher in active IBD and in UC compared with Crohn’s disease (p = 0.0013), but categorization of these patient groups did not take place. HBD-2 did not categorize any of the studied groups.

CONCLUSIONS

Calprotectin was the best fecal marker in pediatric IBD, but MMP-9 showed almost comparable performance in UC, suggesting applicability as a surrogate marker of inflammation. Fecal HBD-2 did not bring information to the disease characteristics of pediatric IBD patients.

Matrix metalloproteinase-10 plays an active role in microvascular complications in type 1 diabetic patients

AIMS/HYPOTHESIS

The role of metalloproteinase-10 (MMP-10) in type 1 diabetes is not known. We hypothesise that it plays a role in the onset and progression of diabetic nephropathy and retinopathy.

METHODS

Serum MMP-10 levels from 269 patients with type 1 diabetes were measured, and their association with microvascular complications was analysed. We also studied whether knocking out the Mmp10 gene influenced the extent of renal injury and retinal damage in a streptozotocin-induced diabetic mouse model.

RESULTS

The risk of nephropathy and proliferative retinopathy associated with the highest vs the lowest MMP-10 tertile was increased three to four times independently of the classical risk factors. Accordingly, renal function and morphology were better preserved in diabetic Mmp10 −⁄− mice than in their Mmp10 +/+ counterparts. There were more kidney-infiltrating macrophages in diabetic Mmp10+/+ mice, suggesting that MMP-10 contributes to the inflammatory response leading to microvascular complications. The loss of neuronal cells in the retinas of diabetic Mmp10 +/+ mice was higher than in Mmp10 −⁄− mice. Retinal inflammation was decreased in Mmp10 −⁄− mice, as indicated by their reduced retinal caspase-1 levels.

CONCLUSIONS/INTERPRETATION

MMP-10 is involved in the development of microvascular complications in type 1 diabetes and emerges as a potential therapeutic target for slowing down the evolution of diabetic nephropathy and retinopathy.

EMerging BiomARKers in Inflammatory Bowel Disease (EMBARK) study identifies fecal calprotectin, serum MMP9, and serum IL-22 as a novel combination of biomarkers for Crohn's disease activity: role of cross-sectional imaging

OBJECTIVES

In Crohn's disease (CD), clinical symptoms correspond poorly to inflammatory disease activity. Biomarkers reflective of mucosal and bowel wall inflammation would be useful to monitor disease activity. The EMBARK study evaluated disease activity in patients with ulcerative colitis (UC) and CD, and used endoscopy with or without cross-sectional imaging for biomarker discovery.

METHODS

UC (n=107) and CD (n=157) patients were characterized and underwent ileocolonoscopy (ICO). A subset of CD patients (n=66) also underwent computed tomography enterography (CTE). ICO and CTE were scored by a gastroenterologist and radiologist who incorporated findings of inflammation into a single score (ICO-CTE) for patients that underwent both procedures. Serum and fecal biomarkers were evaluated for association with the Mayo Clinic endoscopy score in UC patients and with ICO alone or ICO-CTE in CD patients. Individual biomarkers with a moderate degree of correlation (P≤0.3) were evaluated using multivariate analysis with model selection using a stepwise procedure.

RESULTS

In UC, ordinal logistic regression using Mayo Clinic endoscopy subscore selected the combination of fecal calprotectin and serum matrix metalloproteinase 9 (MMP9; pseudo R(2)=0.353). In CD, we found that use of the ICO-CTE increased specificity of known biomarkers. Using ICO-CTE as the dependent variable for biomarker discovery, the selected biomarkers were the combination of fecal calprotectin, serum MMP9, and serum IL-22 (r=0.699).

CONCLUSIONS

Incorporation of both ICO and CTE into a single measure increased biomarker performance in CD. Combinations of fecal calprotectin and serum MMP9 for UC, and combinations of fecal calprotectin, serum MMP9, and serum interleukin-22 in CD, demonstrated the strongest association with imaging/endoscopy-defined inflammation.

Low trypsinogen-1 expression in pediatric ulcerative colitis patients who undergo surgery

AIM: To investigate whether matrix metalloproteinases-9 (MMP-9) or trypsinogens could serve as histological markers for an aggressive disease course in pediatric ulcerative colitis (UC).

METHODS: We identified 24 patients with pediatric onset (≤ 16 years) UC who had undergone surgery during childhood/adolescence a median of 2.1 years (range 0.1-7.4 years) after the diagnosis (between 1990 and 2008) in Children’s Hospital, Helsinki, Finland. We also identified 27 conservatively treated UC patients and matched them based on their age at the time of diagnosis and follow-up at a median of 6 years (range 3-11 years) to serve as disease controls. Twenty children for whom inflammatory bowel disease (IBD) had been excluded as a result of endoscopy served as non-IBD controls. Colon biopsies taken by diagnostic endoscopy before the onset of therapy were stained using immunohistochemistry to study the expression of MMP-9, trypsinogen-1 (Tryp-1), Tryp-2, and a trypsin inhibitor (TATI). The profiles of these proteases and inhibitor at diagnosis were compared between the surgery group, the conservatively treated UC patients and the non-IBD controls.

RESULTS: The proportions of Tryp-1 and Tryp-2 positive samples in the colon epithelium and in the inflammatory cells of the colon stroma were comparable between the studied groups at diagnosis. Interestingly, the immunopositivity of Tryp-1 (median 1; range 0-3) was significantly lower in the epithelium of the colon in the pediatric UC patients undergoing surgery when compared to that of the conservatively treated UC patients (median 2; range 0-3; P = 0.03) and non-IBD controls (median 2; range 0-3; P = 0.04). For Tryp-2, there was no such difference. In the inflammatory cells of the colon stroma, the immunopositivities of Tryp-1 and Tryp-2 were comparable between the studied groups at diagnosis. Also, the proportion of samples positive for TATI, as well as the immunopositivity, was comparable between the studied groups in the colon epithelium. In the stromal inflammatory cells of the colon, TATI was not detected. In UC patients, there were significantly more MMP-9 positive samples and a higher immunopositivity in the stromal inflammatory cells of the colon when compared to the samples from the non-IBD patients (P = 0.006 and P = 0.002, respectively); the immunopositivity correlated with the histological grade of inflammation (95%CI: 0.22-0.62; P = 0.0002), but not with the other markers of active disease. There were no differences in the immunopositivity or in the proportions of MMP-9 positive samples when examined by epithelial staining. The staining profiles in the ileal biopsies were comparable between the studied groups for all of the studied markers.

CONCLUSION: For pediatric UC patients who require surgery, the immunopositivity of Tryp-1 at diagnosis is lower when compared to that of patients with a more benign disease course.

Matrix metalloproteinases in the restorative proctocolectomy pouch of pediatric ulcerative colitis

AIM: To investigate matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in pouch mucosa of pediatric onset ulcerative colitis (UC).

METHODS: In this cross-sectional study, 28 patients with pediatric onset UC underwent ileal pouch biopsy 13 years (median) after proctocolectomy. Expression of MMPs-3, -7, -8, -9, -12 and -26 and TIMPs-1, -2 and -3 in samples was examined using immunohistochemichal methods, and another biopsy was used to evaluate the grade of histological inflammation. Two investigators independently graded the immunohistochemical specimens in a semiquantitative fashion, using a scale marking staining intensity as follows: 0 = less than 20 positive cells; 1 = 20-50 positive cells; 2 = 50-200 positive cells; 3 = over 20 positive cells. Fecal calprotectin and blood inflammatory markers [serum C-reactive protein (CRP) and erythrocyte sedimentation rate] were determined during a follow-up visit to examine correlations between these markers and the expression of MMPs and TIMPs.

RESULTS: Of the 28 patients with pediatric onset UC, nine had not experienced pouchitis, whereas thirteen reported a single episode, and six had recurrent pouchitis (≥ 4 episodes). At the time of the study, six patients required metronidazole. In all of the others, the most recent episode of pouchitis had occurred over one month earlier, and none were on antibiotics. Only four samples depicted no sign of inflammation, and these were all from patients who had not had pouchitis. Two samples were too small to determine the grade of inflammation, but both had suffered pouchitis, the other recurrent. No sample depicted signs of colonic metaplasia. Most pouch samples showed expression of epithelial (e) and stromal (s) MMP-3 (e, n = 22; s, n = 20), MMP-7 (e, n = 28; s, n = 27), MMP-12 (e, n = 20; s, n =24), TIMP-2 (e, n = 23; s, n = 23) and MMP-3 (e, n = 23; s, n = 28) but MMP-8 (e, n = 0; s, n = 1), MMP-9 (e, n = 0; s, n = 9) and MMP-26 (e, n = 0; s, n = 3) and TIMP-1 (n = 0, both) were lacking. In samples with low grade of inflammatory activity, the epithelial MMP-3 and MMP-7 expression was increased (r = -0.614 and r = -0.472, respectively, P < 0.05 in both). MMPs and TIMPs did not correlate with the markers of inflammation, fecal calprotectin, erythrocyte sedimentation rate, or CRP, with the exception of patients with low fecal calprotectin (< 100 μg/g) in whom a higher expression of epithelial MMP-7 was found no differences in MMP- or TIMP-profiles were seen in patients with a history of pouchitis compared to ones with no such episodes. Anastomosis with either straight ileoanal anastomosis or ileoanal anastomosis with J-pouch did depict differences in MMP- or TIMP-expression.

CONCLUSION: The expression of MMPs pediatric UC pouch in the long-term shares characteristics with inflammatory bowel disease, but inflammation cannot be classified as a reactivation of the disease.

Serum MMPs 7-9 and their inhibitors during glucocorticoid and anti-TNF-α therapy in pediatric inflammatory bowel disease

OBJECTIVES

In inflammatory bowel diseases (IBD), matrix metalloproteinases (MMPs) participate in intestinal tissue damage and regenerative processes. MMP activity is inhibited by tissue inhibitors of MMPs (TIMPs) and plasma inhibitor, α₂-macroglobulin (α2M). We evaluated serum MMPs, their inhibitors and markers of neutrophil activity, myeloperoxidase (MPO) and human neutrophil elastase (HNE), during glucocorticoid (GC) and anti-TNF-α therapies in pediatric IBD, in aim to find new tools for assessment of therapeutic response.

METHODS

Serum samples were collected before and within a month after the start of therapy with oral GC (n = 19) or anti-TNF-α agent (n = 16), and from 32 pediatric control patients. Serum levels of MMP-7, MMP-9, TIMP-1, TIMP-2, α2M, MPO, and HNE were analyzed with enzyme-linked immunoabsorbent assays (ELISA) and MMP-8 by immunofluorometric assay (IFMA). Disease activity was monitored with erythrocyte sedimentation rate (ESR), CRP, fecal calprotectin (FC), and physician's global assessment of clinical disease activity (PGA).

RESULTS

In IBD, pretreatment serum MMP-7, MMP-8, MMP-9, α2M, MPO, and HNE were elevated compared with controls. During GC therapy, MMP-7, TIMP-1, and MMP-7/TIMP-2 decreased (all p < 0.05). During anti-TNF-α therapy, MMP-7 decreased (p = 0.063), but remained higher than that after GC therapy (p < 0.05). α2M (p < 0.05) and HNE (p < 0.05) increased, the former higher than that in GC-treated patients. The levels of MMPs and their inhibitors did not markedly associate with inflammatory markers in blood or feces.

CONCLUSIONS

In pediatric IBD, serum MMP-7 mirrors disease activity, and together with TIMP-1, reflects GC therapy response. α₂-Macroglobulin expression parallels the anti-TNF-α response.

Iatrogenic extracellular matrix disruption as a local trigger for postoperative ileus

BACKGROUND

Active matrix metallopeptidase 9 (MMP-9) disruption of the extracellular matrix (ECM) plays an important role in inflammatory disorders. In this study, we investigated the inflammatory role of MMP-9 and the ECM breakdown product hyaluronan as a trigger for the postoperative intestinal inflammatory response of postoperative ileus.

METHODS

We performed a standardized intestinal surgical manipulation on rats to produce ileus assessed by the oral non-digestible fluorescein isothiocyanate-dextran transit assay. We studied isolated intestinal muscularis extracts for mRNA expressions of interleukin 6 (IL-6), MMP-9 and CD44. We quantified peritoneal MMP-9 activity using zymography, and quantified peritoneal fluid and serum for hyaluronan and tissue inhibitor of metalloproteinase 1 levels by enzyme-linked immunosorbent assay (ELISA). We cultured peritoneal macrophages and exposed them to peritoneal fluid or synthetic hyaluronan for ELISA analysis of IL-6 and macrophage inflammatory protein-1α.

RESULTS

Transit was significantly delayed after surgical manipulation, and extracts of the isolated jejunal and colonic muscularis demonstrated a significant induction of IL-6, MMP-9, and CD44 mRNAs compared with controls. Zymography confirmed significant MMP-9 activity in peritoneal fluid compared with controls. Enzyme-linked immunosorbent assay measurements showed a significant up-regulation in hyaluronan and tissue inhibitor of metalloproteinase 1 in the peritoneal fluid and serum. In addition, ELISA and reverse transcriptase-polymerase chain reaction measurements of peritoneal macrophages stimulated with postsurgical peritoneal fluid and synthetic hyaluronan resulted in higher expressions of IL-6 and macrophage inflammatory protein-1α in the macrophage supernatant.

CONCLUSIONS

Our results confirm that MMP-9 disruption in the ECM with hyaluronan release and muscularis CD44 receptor induction has the potential to trigger muscularis proinflammatory cascades that cause postoperative ileus. Matrix metallopeptidase 9 inhibition may be a novel therapeutic approach to limit postoperative ileus.

Comparative analysis of the expression of metalloproteases and their inhibitors in resected crohn's disease and complicated diverticular disease

BACKGROUND

Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs), are expressed in the gastrointestinal tract by different cellular types. Nevertheless, the imbalance between MMPs and TIMPs plays an important role in the physiopathology of diverse intestinal inflammatory processes.

METHODS

An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs -1, -2, -7, -9, -11, -13, -14, and TIMPs -1, -2 and -3. Immunohistochemical staining of intestinal samples from surgical interventions from 30 patients with complicated Crohn's disease (CD) and 25 patients with diverticulitis were performed at the inflamed mucosa and in adjacent noninflamed mucosa. A reverse-transcription polymerase chain reaction (RT-PCR) analysis was performed to confirm the results obtained by immunohistochemistry. In addition, western blot experiments were carried out.

RESULTS

CD inflamed mucosa showed higher global expression of MMP-2, MMP-9, and MMP-13 than diverticulitis inflamed mucosa. However, inflamed and noninflamed diverticulitis mucosal samples showed higher global expression of MMP-1, TIMP-1, and 3 than the CD samples. Epithelial cells of inflamed mucosa showed higher expression of MMP-2, 9, and 13 in CD than diverticulitis. However, the latter showed higher expression of TIMP-1. Similar differences for fibroblast-like cells and mononuclear inflammatory cells were found. CD samples presented an increased expression of MMPs and a decreased expression of TIMPs compared to diverticulitis.

CONCLUSIONS

These results indicate a differential pattern of expression of MMPs and TIMPs in CD and diverticulitis and the necessity to study the potential role of MMP inhibitors as new protective agents in both diseases.

Candidate mucosal and surrogate biomarkers of inflammatory bowel disease in the era of new technology

OBJECTIVE

There is increasing knowledge of the pathophysiology behind inflammatory bowel disease (IBD) although the exact mechanism is far from fully understood. In the era of new technology, over the last years molecular approaches have shed light on the inflammatory mechanisms and their metabolic end products. This opens for a molecular fingerprinting that can be used in the biomarker field of IBD. There is a great need of biomarkers for prediction of clinical outcome and prognostic biomarker for prediction of therapeutic effects in IBD. Although the biomarker concept is old, so far very few really useful biomarkers exist in IBD.

MATERIAL AND METHODS

Here, we review the predictive and prognostic biomarkers in IBD in the era of new technologies with emphasis on the potential of molecular fingerprinting.

RESULTS

Very few candidate biomarkers have been documented. The most promising candidate predictor is tumor necrosis factor-α, but there is a lack of validation.

CONCLUSION

So far, there are few biomarkers documented in IBD, but we are at the start of a new scientific field that will be of great value for the handling of the disease.

Serum immune-activation potency and response to anti-TNF-α therapy in Crohn's disease

AIM: To study whether immune-activation stage in serum of adult Crohn’s disease (CD) patients correlates with disease activity and with treatment response to anti-tumor necrosis factor-α (TNF-α) therapy.

METHODS: Serum samples were obtained from 15 adult CD patients introduced to anti-TNF-α therapy. The individual stage of immune activation was studied applying our new in vitro assay, in which target cells (donor derived peripheral blood mononuclear cells) were cultured with patient serum and the T-cell activation induced by the patient serum was studied using a panel of markers for effector [interferon γ (IFNγ), interleukin (IL)-5] and regulatory T-cells [forkhead transcription factor 3 (FOXP3) and glucocorticoid-induced tumour necrosis factor receptor (GITR)]. The endoscopic disease activity was assessed with the Crohn’s disease endoscopic index of severity (CDEIS) before and 3 mo after therapy with an anti-TNF-α agent.

RESULTS: Low induction of FOXP3 and GITR in target cells cultured in the presence of patient serum was associated with high disease activity i.e. CDEIS assessed before therapy (r = -0.621, P = 0.013 and r = -0.625, P = 0.013, respectively). FOXP3 expression correlated inversely with pre-treatment erythrocyte sedimentation rate (r = -0.548, P = 0.034). Low serum induced FOXP3 (r = -0.600, P = 0.018) and GITR (r = -0.589, P = 0.021) expression and low IFNγ secretion from target cells (r = -0.538, P = 0.039) associated with treatment response detected as a decrease in CDEIS.

CONCLUSION: The immune-activation potency in the patient serum prior to anti-TNF-α therapy reflected intestinal inflammation and the therapeutic response.

Expression profiles of matrix metalloproteinases and their inhibitors in colonic inflammation related to pediatric inflammatory bowel disease

OBJECTIVE

The differential diagnosis of chronic colitis in inflammatory bowel disease (IBD) is challenging and a distinction between Crohn's disease (CD) and ulcerative colitis (UC) is not always possible. Matrix metalloproteinases (MMPs) cleave components of the extracellular matrix and their dysregulation leads to damage to the mucosa. They are involved in inflammation in IBD, as well as in eventual tissue repair. We aimed to examine putative differences in the profiles of MMPs and their tissue inhibitors [tissue inhibitors of metalloproteinase (TIMPs)] in pediatric IBD to find better tools for differential diagnosis of various IBD subgroups at the tissue level in the colon.

MATERIAL AND METHODS

Expression of MMPs -1, -7, -8, -9, -10, -12 and -26 and TIMPs -1 and -3 was studied by immunohistochemistry in colonic tissue samples of 32 pediatric patients with IBD and 11 non-IBD cases.

RESULTS

In the colon, expression of MMP-7 in epithelium was greater in CD samples compared to UC samples (1.09 versus 0.33; P = 0.010). Furthermore, epithelial MMP-10 expression was elevated in CD and UC samples compared to non-IBD samples (1.55 versus 1.00; P = 0.041 and 1.58 versus 1.00; P = 0.025, respectively). TIMP-3 expression in the stroma was higher in both the CD and UC groups when compared to non-IBD samples (2.18 versus 1.36; P = 0.026 and 2.50 versus 1.36; P = 0.002, respectively), but differences between UC and CD could not be observed.

CONCLUSIONS

Increased expression of epithelial MMP-10 and stromal TIMP-3 could serve as histological indicators of IBD etiology. Epithelial MMP-7 expression, on the other hand, could help to differentiate between CD-related colitis and UC.