Anti-fibrogenic Potential of Mesenchymal Stromal Cells in Treating Fibrosis in Crohn's Disease

Inflammation-fibrosis interplay in inflammatory bowel disease: mechanisms, progression, and therapeutic strategies

Background

The incidence of intestinal fibrosis in Inflammatory bowel disease has increased in recent years, and the repair process is complex, leading to substantial economic and social burdens. Therefore, understanding the pathogenesis of intestinal fibrosis and exploring potential therapeutic agents is crucial.

Purpose

This article reviews the pathogenesis of IBD-related intestinal fibrosis, potential therapeutic targets, and the progress of research on Traditional Chinese Medicine (TCM) in inhibiting intestinal fibrosis. It also provides foundational data for developing innovative drugs to prevent intestinal fibrosis.

Methods

This article reviews the literature from the past decade on advancements in the cellular and molecular mechanisms underlying intestinal fibrosis. Data for this systematic research were obtained from electronic databases including PubMed, CNKI, SciFinder, and Web of Science. Additionally, a comprehensive analysis was conducted on reports regarding the use of TCM for the treatment of intestinal fibrosis. The study synthesizes and summarizes the research findings, presenting key patterns and trends through relevant charts.

Results

This study reviewed recent advancements in understanding the cellular and molecular mechanisms of intestinal fibrosis, the active ingredients of TCM that inhibit intestinal fibrosis, the efficacy of TCM formulae in preventing intestinal fibrosis, and dietary modification that may contribute to the inhibition of intestinal fibrosis.

Conclusion

This article examines the cellular and molecular mechanisms that promote the development of intestinal fibrosis, as well as potential therapeutic targets for its treatment. It also provides a theoretical basis for exploring and utilizing TCM resources in the management of intestinal fibrosis. Through the analysis of various TCM medicines, this article underscores the clinical significance and therapeutic potential of TCM and dietary modifications in treating intestinal fibrosis.

Small extracellular vesicles derived from adipose mesenchymal stem cells alleviate intestinal fibrosis by inhibiting the FAK/Akt signaling pathway via MFGE8

BACKGROUND

Intestinal fibrosis is one of the most frequent and severe complications of Crohn's disease. Accumulating studies have reported that adipose mesenchymal stem cell-derived small extracellular vesicles (AMSC-sEVs) could alleviate renal fibrosis, hepatic fibrosis, etc., while their potential for treating intestinal fibrosis remains uncertain. Therefore, this study aims to determine the therapeutic effects of AMSC-sEVs on intestinal fibrosis and identify the mechanisms underlying these effects.

METHODS

AMSC-sEVs were characterized using transmission electron microscopy, nanoparticle tracking analysis, and western blot. Whether AMSC-sEVs exert antifibrotic effects was investigated in two different murine models of intestinal fibrosis. Besides, AMSC-sEVs were co-cultured with primary human fibroblasts and CCD18co during transforming growth factor (TGF)-β1 stimulation. Label-free proteomics and rescue experiments were performed to identify candidate molecules in AMSC-sEVs. Transcriptome sequencing revealed changes in mRNA levels among different groups. Lastly, proteins related to relevant signaling pathways were identified by western blotting, and their expression and activation status were assessed.

RESULTS

AMSC-sEVs positively expressed CD63 and Alix and presented a classical "rim of a cup" and granule shape with approximately 43-100 nm diameter. AMSCs significantly alleviated intestinal fibrosis through secreted sEVs in vitro and in vivo. The milk fat globule-EGF factor 8 (MFGE8) was stably enriched in AMSC-sEVs and was an active compound contributing to the treatment of intestinal fibrosis by AMSCs. Mechanistically, AMSC-sEV-based therapies attenuated intestinal fibrosis by inhibiting the FAK/Akt signaling pathway.

CONCLUSIONS

MFGE8-containing AMSC-sEVs attenuate intestinal fibrosis, partly through FAK/Akt pathway inhibition.

Adipose-derived mesenchymal stromal cells alleviate intestinal fibrosis: The role of tumor necrosis factor-stimulated gene 6 protein

BACKGROUND

The therapeutic potential of adipose-derived mesenchymal stromal cells (AMSCs) in the treatment of intestinal fibrosis occured in patients with Crohn's disease (CD) remains unclear. Tumor necrosis factor-stimulated gene 6 (TSG6) protein plays a critical role in inflammation regulation and tissue repair. This study aimed to determine if AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein and explore the underlying mechanisms.

METHODS

Two murine models for intestinal fibrosis were established using 2,4,6-trinitrobenzene sulfonic acid in BALB/c mice and dextran sulfate sodium in C57BL/6 mice. Primary human fibroblasts and CCD-18co cells were incubated with transforming growth factor (TGF)-β1 to build two fibrosis cell models in vitro.

RESULTS

Intraperitoneally administered AMSCs attenuated intestinal fibrosis in the two murine models, as evidenced by significant alleviation of colon shortening, collagen protein deposits, and submucosal thickening, and also decrease in the endoscopic and fibrosis scores (P < 0.001). Although intraperitoneally injected AMSCs did not migrate to the colon lesions, high levels of TSG6 expression and secretion were noticed both in vivo and in vitro. Similar to the role of AMSCs, injection of recombinant human TSG6 attenuated intestinal fibrosis in the mouse models, which was not observed with the administration of AMSCs with TSG6 knockdown or TSG6 neutralizing antibody. Mechanistically, TSG6 alleviates TGF-β1-stimulated upregulation of α-smooth muscle actin (αSMA) and collagen I by inhibiting Smad2 phosphorylation. Furthermore, the expression of TSG6 is lower in intestinal fibrosis tissue of patients with Crohn's disease and can reduce pro-fibrotic protein (αSMA) secretion from primary ileal fibrotic tissue.

CONCLUSIONS

AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein, which inhibits Smad2 phosphorylation. TSG6, a novel anti-fibrotic factor, could potentially improve intestinal fibrosis treatments.

Endoscopic Management of Strictures in Crohn's Disease: An Unsolved Case

Crohn's disease (CD) is a chronic inflammatory disease associated with a significant burden in terms of quality of life and health care costs. It is frequently associated with several complications, including the development of intestinal strictures. Stricturing CD requires a careful multidisciplinary approach involving medical therapy and surgery, still posing a continuous management challenge; in this context, endoscopic treatment represents a valuable, in-between opportunity as a minimally invasive strategy endorsed by extensive yet heterogeneous evidence and evolving research and techniques. This review summarizes current knowledge on the role of therapeutic endoscopy in stricturing CD, focusing on evidence gaps, recent updates, and novel techniques intended for optimizing efficacy, safety, and tailoring of this approach in the view of precision endoscopy.

Identification of genes related to growth and amino acid metabolism from the transcriptome profile of the liver of growing laying hens

The growing period is a critical period for the growth and development of hens and affects their production performance during the laying period. During the early stage of growing, bone and muscle growth is rapid, making it necessary to provide sufficient amino acids (AA) to support the growth and development of laying hens. In this experiment, RNA-Sequencing (RNA-Seq) was applied to compare the liver tissues from 6- to 12-wk-old growing laying hens to identify candidate genes related to growth and AA transport and metabolism. In the liver tissues, 596 differentially expressed genes (DEG) were identified, of which 424 genes were up-regulated and 172 were down-regulated. Through enrichment analysis and DEGs analysis, some DEGs and pathways related to AA transport and metabolism were identified. Additionally, there were significantly increased activities in the liver of glutamate dehydrogenase (GDH), glutamic oxaloacetic transaminase (GOT), and glutamate pyruvate transaminase (GPT). Meanwhile, the level of serum insulin-like growth factor binding protein-5 (IGFBP-5) significantly elevated, and insulin-like growth factor-1 (IGF-1) levels significantly reduced at 12 wk compared to 6 wk. The AA contents in the breast muscle were not significantly altered, while the levels of the free AA in the serum underwent significant changes. This study discovered that the transport and metabolism of AAs in growing laying hens at different ages changed, which influenced the growth and development of growing laying hens. This contributes to future research on the mechanisms of growth and AA metabolism during the growing period of laying hens.

Role of the epithelial barrier in intestinal fibrosis associated with inflammatory bowel disease: relevance of the epithelial-to mesenchymal transition

In inflammatory bowel disease (IBD), chronic inflammation in the gastrointestinal tract can lead to tissue damage and remodelling, which can ultimately result in fibrosis. Prolonged injury and inflammation can trigger the activation of fibroblasts and extracellular matrix (ECM) components. As fibrosis progresses, the tissue becomes increasingly stiff and less functional, which can lead to complications such as intestinal strictures, obstructive symptoms, and eventually, organ dysfunction. Epithelial cells play a key role in fibrosis, as they secrete cytokines and growth factors that promote fibroblast activation and ECM deposition. Additionally, epithelial cells can undergo a process called epithelial-mesenchymal transition, in which they acquire a more mesenchymal-like phenotype and contribute directly to fibroblast activation and ECM deposition. Overall, the interactions between epithelial cells, immune cells, and fibroblasts play a critical role in the development and progression of fibrosis in IBD. Understanding these complex interactions may provide new targets for therapeutic interventions to prevent or treat fibrosis in IBD. In this review, we have collected and discussed the recent literature highlighting the contribution of epithelial cells to the pathogenesis of the fibrotic complications of IBD, including evidence of EMT, the epigenetic control of the EMT, the potential influence of the intestinal microbiome in EMT, and the possible therapeutic strategies to target EMT. Finally we discuss the pro-fibrotic interactions epithelial-immune cells and epithelial-fibroblasts cells.

Stem Cell Therapy in Inflammatory Bowel Disease: A Review of Achievements and Challenges

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a group of chronic inflammatory diseases of the gastrointestinal tract. Repeated inflammation can lead to complications, such as intestinal fistula, obstruction, perforation, and bleeding. Unfortunately, achieving durable remission and mucosal healing (MH) with current treatments is difficult. Stem cells (SCs) have the potential to modulate immunity, suppress inflammation, and have anti-apoptotic and pro-angiogenic effects, making them an ideal therapeutic strategy to target chronic inflammation and intestinal damage in IBD. In recent years, hematopoietic stem cells (HSCs) and adult mesenchymal stem cells (MSCs) have shown efficacy in treating IBD. In addition, numerous clinical trials have evaluated the efficiency of MSCs in treating the disease. This review summarizes the current research progress on the safety and efficacy of SC-based therapy for IBD in both preclinical models and clinical trials. We discuss potential mechanisms of SC therapy, including tissue repair, paracrine effects, and the promotion of angiogenesis, immune regulation, and anti-inflammatory effects. We also summarize current SC engineering strategies aimed at enhancing the immunosuppressive and regenerative capabilities of SCs for treating intestinal diseases. Additionally, we highlight current limitations and future perspectives of SC-related therapy for IBD.

hucMSC-Ex Alleviates IBD-Associated Intestinal Fibrosis by Inhibiting ERK Phosphorylation in Intestinal Fibroblasts

Background

Intestinal fibrosis, one of the complications of inflammatory bowel disease (IBD), is associated with fistula and intestinal stricture formation. There are currently no treatments for fibrosis. Mesenchymal stem cell-derived exosomes have been proven to exert inhibitory and reversal effects in IBD and other organ fibrosis. In this study, we explored the role of human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Ex) in IBD-related fibrosis and its associated mechanism to provide new ideas for the prevention and treatment of IBD-related intestinal fibrosis.

Methods

We established a DSS-induced mouse IBD-related intestinal fibrosis model and observed the effect of hucMSC-Ex on the mouse model. We also used the TGF-induced human intestinal fibroblast CCD-18Co to observe the role of hucMSC-Ex in the proliferation, migration, and activation of intestinal fibroblasts. Having observed that the extracellular-signal-regulated kinase (ERK) pathway in intestinal fibrosis can be inhibited by hucMSC-Ex, we treated intestinal fibroblasts with an ERK inhibitor to emphasize the potential target of ERK phosphorylation in the treatment of IBD-associated intestinal fibrosis.

Results

In the animal model of IBD-related fibrosis, hucMSC-Ex alleviated inflammation-related fibrosis as evident in the thinning of the mice's intestinal wall and decreased expression of related molecules. Moreover, hucMSC-Ex inhibited TGF-β-induced proliferation, migration, and activation of human intestinal fibroblasts, and ERK phosphorylation played a key role in IBD-associated fibrosis. The inhibition of ERK decreased the expression of fibrosis-related indicators such as α-SMA, fibronectin, and collagen I.

Conclusion

hucMSC-Ex alleviates DSS-induced IBD-related intestinal fibrosis by inhibiting profibrotic molecules and intestinal fibroblast proliferation and migration by decreasing ERK phosphorylation.

Use of Mesenchymal Stem Cells in Crohn's Disease and Perianal Fistulas: A Narrative Review

Crohn's Disease (CD), which usually leads to anal fistulas among patients, is the most important inflammatory bowel disease that causes morbidity in many people around the world. This review article proposes using MSCs as a hopeful therapeutic strategy for CD and anal fistula treatment in both preclinical and clinical conditions. Finally, darvadstrocel, a cell-based medication to treat complex anal fistulas in adults, as the only European Medicines Agency (EMA)-approved product for the treatment of anal fistulas in CD is addressed. Although several common therapies, such as surgery and anti-tumor necrosis factor-alpha (TNF-α) drugs as well as a combination of these methods is used to improve this disease, however, due to the low effectiveness of these treatments, the use of new strategies with higher efficiency is still recommended. Cell therapy is among the new emerging therapeutic strategies that have attracted great attention from clinicians due to its unique capabilities. One of the most widely used cell sources administrated in cell therapy is mesenchymal stem cell (MSC). This review article will discuss preclinical and clinical studies about MSCs as a potent and promising therapeutic option in the treatment of CD and anal fistula.

MFE40-the active fraction of Mume Fructus alcohol extract-alleviates Crohn's disease and its complications

ETHNOPHARMACOLOGICAL RELEVANCE

Mume Fructus (MF) is a well-known traditional Chinese medicine used to treat chronic cough, prolonged diarrhea, and other inflammation-related diseases. We previously confirmed the anti-colitis effect of its ethanol extract on a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced Crohn's disease (CD) rat model. However, the active ingredients and underlying mechanisms of MF remain unknown.

AIM OF THE STUDY

To clarify the material basis and potential mechanism of the ethanol extract of MF (MFE) in alleviating CD and its complications, such as lung injury and intestinal obstruction.

MATERIALS AND METHODS

MF was extracted with 80% ethanol aqueous solution and separated with 0, 40, and 100% ethanol aqueous solutions. MFE and its fractions were screened in a TNBS-induced CD rat model. For the bioactive fraction, the chemical composition was identified and quantified using ultrahigh-performance liquid chromatography coupled with diode-array detection and quadrupole time-of-flight tandem mass spectrometry. Interleukin (IL)-1β, IL-6, IL-17, transforming growth factor (TGF)-β, and lipopolysaccharide (LPS) levels in the colon, lungs, and/or plasma were detected using enzyme-linked immunosorbent assays. The expression levels of zonula occludens-1 (ZO-1) and occludin in the colon were measured using immunohistochemical staining, and the intestinal microbiota and short-chain fatty acid (SCFA) levels were analyzed using 16S rRNA gene sequencing and gas chromatography/mass spectrometry.

RESULTS

The 40% ethanol fraction of MF (MFE40), which mainly contained methyl citrate, ethyl citrate, and caffeoylquinic acid ethyl esters, was identified as the active fraction that could alleviate CD in rats. MFE40 could ameliorate inflammation and fibrosis in the colon and lung tissues by inhibiting the secretion of cytokines, such as IL-1β, IL-6, IL-17, and TGF-β, along with intestinal obstruction and lung injury in CD rats. The possible mechanisms of MFE40 were related to increased expression of ZO-1 and occludin in the colon, reduction in plasma LPS levels, and restoration of SCFAs via reduction in the relative abundance of Adlercreutzia, Clostridium_sensu_stricto_1, Erysipelatoclostridium, Faecalibaculum, norank_f_Erysipelotrichaceae, Phascolarctobacterium Coriobacteriaceae_UGG_002, and Allobaculum and increase in the relative abundance of Escherichia shigella, Christensenella, Acetivibrio_ethanolgignens, and Butyricicoccus. MFE40 had no significant influence on the inflammatory factors in healthy rats.

CONCLUSIONS

Citrate esters and hydroxycinnamate esters are the main active constituents of MFE40. MFE40 exhibited a remission effect on CD rats and inhibited intestinal obstruction and lung injury via anti-inflammatory effects and regulation of the intestinal microbiota-gut-lung homeostasis.

Adiponectin Alleviates Intestinal Fibrosis by Enhancing AMP-Activated Protein Kinase Phosphorylation

BACKGROUND

Intestinal fibrosis is a common complication of Crohn's disease (CD). Adiponectin reportedly exerts anti-inflammatory effects in various disease models, including colitis models.

AIMS

In this study, we aimed to determine the effects of adiponectin on intestinal fibrosis and the underlying mechanisms.

METHODS

A murine model of intestinal fibrosis was established by administering increasing doses of 2,4,6-trinitrobenzene sulfonic acid to Balb/c mice via enema for 7 weeks. Primary human fibroblasts were isolated from the colon tissues of patients with CD. The fibroblasts were incubated with transforming growth factor (TGF)-β1 to establish a fibrosis model in vitro. Pathway inhibitors were used to verify the potential signaling pathways involved in the anti-fibrogenic effect of adiponectin.

RESULTS

Compared with the normal mesentery, adiponectin expression was significantly increased in the hypertrophic mesentery of patients with CD. Intraperitoneal injection of adiponectin significantly decreased the activity of myeloperoxidase and the expression of pro-inflammatory cytokines (tumor necrosis factor α and interleukin 6) in the colon of fibrosis model mice, whereas the expression of the anti-inflammatory cytokine interleukin 10 was substantially increased. Moreover, adiponectin treatment inhibited colon shortening, decreased colon weight, and reduced fibrotic protein deposition in the model mice. Adiponectin reduced the phosphorylation of Smad2 and collagen deposition induced by TGF-β1 in primary human intestinal fibroblasts, with an increase in AMP-activated protein kinase (AMPK) phosphorylation. Furthermore, this phenomenon was reversed by the AMPK inhibitor.

CONCLUSIONS

Adiponectin can protect against intestinal fibrosis by enhancing the phosphorylation of AMPK and inhibiting the activity of the TGF-β1/Smad signaling pathway.

Intestinal Fibrosis in Inflammatory Bowel Disease and the Prospects of Mesenchymal Stem Cell Therapy

Intestinal fibrosis is an important complication of inflammatory bowel disease (IBD). In the course of the development of fibrosis, certain parts of the intestine become narrowed, significantly destroying the structure and function of the intestine and affecting the quality of life of patients. Chronic inflammation is an important initiating factor of fibrosis. Unfortunately, the existing anti-inflammatory drugs cannot effectively prevent and alleviate fibrosis, and there is no effective anti-fibrotic drug, which makes surgical treatment the mainstream treatment for intestinal fibrosis and stenosis. Mesenchymal stem cells (MSCs) are capable of tissue regeneration and repair through their self-differentiation, secretion of cytokines, and secretion of extracellular vesicles. MSCs have been shown to play an important therapeutic role in the fibrosis of many organs. However, the role of MSC in intestinal fibrosis largely remained unexplored. This review summarizes the mechanism of intestinal fibrosis, including the role of immune cells, TGF-β, and the gut microbiome and metabolites. Available treatment options for fibrosis, particularly, MSCs are also discussed.

Mesenchymal Stem Cell Injection in Crohn's Disease Strictures: A Phase I-II Clinical Study

BACKGROUND AND AIM

Mesenchymal stem cells [MSCs] have anti-inflammatory and anti-fibrotic properties and could be a potential therapy for Crohn's disease [CD] strictures. In this phase I-II pilot trial, we assessed safety and efficacy of local MSC injection to treat CD strictures.

METHODS

CD patients with a short [less than 5 cm in length] non-passable stricture accessible by ileocolonoscopy were included. Allogenic bone-marrow derived MSCs were injected in the four quadrants of the stricture. Adverse events and clinical scores were evaluated at each follow-up visit and endoscopy and magnetic resonance enterography were performed at baseline, Week [W]12 and W48. The main judgement criterion for efficacy was the complete [defined by the ability to pass the ileocolonoscope] or partial [defined by a diameter increase] resolution of the stricture at W12. Second efficacy criteria included assessment of the stricture at W48 and evolution of clinical scores at W12 and W48.

RESULTS

We performed 11 MSC injections in 10 CD patients [three primary and seven anastomotic strictures; one stricture injected twice]. MSC injections were well tolerated but four hospitalisations for occlusion were reported. At W12, five patients presented a complete or partial resolution of the stricture [two complete and three partial]. Seven patients were re-evaluated at W48 [one dilated, one operated, and one lost to follow-up] and four patients had a complete resolution. The evolution of clinical scores between W0, W12, and W48 was not statistically significant.

CONCLUSIONS

MSCs injection in CD stricture was well tolerated and may offer a benefit.

Therapeutic Endoscopy in Postoperative Pouch Complications

Ileal pouch-anal anastomosis (IPAA) or "J"-pouch as it is commonly referred to, is the treatment of choice in patients with medically refractory ulcerative colitis. IPAA can have infectious, inflammatory, and mechanical complications. Currently, there are no Food and Drug Administration-approved medical therapies for these complications. Surgery that may be eventually required can have significant morbidities due to the complexity of IPAA. Endoscopy is fast emerging as a leading modality of treatment for some of these pouch complications. Endoscopy in adjunct with medical treatment can help manage the majority of pouch-related disorders and improve the outcome.

Improving the Efficacy of Mesenchymal Stem/Stromal-Based Therapy for Treatment of Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) consisting of persistent and relapsing inflammatory processes of the intestinal mucosa are caused by genetic, environmental, and commensal microbiota factors. Despite recent advances in clinical treatments aiming to decrease inflammation, nearly 30% of patients treated with biologicals experienced drawbacks including loss of response, while others can develop severe side effects. Hence, novel effective treatments are highly needed. Mesenchymal stem/stromal cell (MSCs) therapy is an innovative therapeutic alternative currently under investigation for IBD. MSCs have the inherent capacity of modulating inflammatory immune responses as well as regenerating damaged tissues and are therefore a prime candidate to use as cell therapy in patients with IBD. At present, MSC-based therapy has been shown preclinically to modulate intestinal inflammation, whilst the safety of MSC-based therapy has been demonstrated in clinical trials. However, the successful results in preclinical studies have not been replicated in clinical trials. In this review, we will summarize the protocols used in preclinical and clinical trials and the novel approaches currently under investigation which aim to increase the beneficial effects of MSC-based therapy for IBD.

The Epithelial-to-Mesenchymal Transition as a Possible Therapeutic Target in Fibrotic Disorders

Fibrosis is a chronic and progressive disorder characterized by excessive deposition of extracellular matrix, which leads to scarring and loss of function of the affected organ or tissue. Indeed, the fibrotic process affects a variety of organs and tissues, with specific molecular background. However, two common hallmarks are shared: the crucial role of the transforming growth factor-beta (TGF-β) and the involvement of the inflammation process, that is essential for initiating the fibrotic degeneration. TGF-β in particular but also other cytokines regulate the most common molecular mechanism at the basis of fibrosis, the Epithelial-to-Mesenchymal Transition (EMT). EMT has been extensively studied, but not yet fully explored as a possible therapeutic target for fibrosis. A deeper understanding of the crosstalk between fibrosis and EMT may represent an opportunity for the development of a broadly effective anti-fibrotic therapy. Here we report the evidences of the relationship between EMT and multi-organ fibrosis, and the possible therapeutic approaches that may be developed by exploiting this relationship.

Mycobacterial Hsp65 antigen delivered by invasive Lactococcus lactis reduces intestinal inflammation and fibrosis in TNBS-induced chronic colitis model

Intestinal fibrosis associated with Crohn's disease (CD), which a common and serious complication of inflammatory bowel diseases. In this context, heat shock proteins (HSPs) might serve as an alternative treatment because these antigens play important roles in the regulation of effector T cells. We thus evaluated the anti-inflammatory and antifibrotic capacities of an invasive and Hsp65-producing strain-Lactococcus lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65)-in chronic intestinal inflammation to assess its potential as an alternative therapeutic strategy against fibrotic CD. Experimental colitis was induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) in BALB/c mice, and the mice were treated orally with L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) via intragastric gavage. The oral administration of this strain significantly attenuated the severity of inflammation and intestinal fibrosis in mice (p < 0.05). These results are mainly justified by reductions in the levels of the pro-fibrotic cytokines IL-13 and TGF-β and increases in the concentration of the regulatory cytokine IL-10. The L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) strain contributed to reductions in the severity of inflammatory damage in chronic experimental CD, and these findings confirm the effectiveness of this new antifibrotic strategy based on the delivery of therapeutic proteins to inside cells of the host intestinal mucosa.

Immunomodulatory Effect of Urine-derived Stem Cells on Inflammatory Bowel Diseases via Downregulating Th1/Th17 Immune Responses in a PGE2-dependent Manner

BACKGROUND AND AIMS

Despite the therapeutic promise of stem cell therapy in the treatment of inflammatory bowel diseases [IBD], most donor cell populations have to be obtained via invasive approaches and often remain insufficiently validated. Urine-derived stem cells [USC] were recently shown to have regenerative properties and can be harvested in a safe, low-cost, and noninvasive way. This study aims to evaluate the immunomodulatory effect of USC and their efficacy in the management of IBD.

METHODS

Human USC were isolated and expanded from the urine of healthy male adult volunteers [n = 3, age range 24-30 years]. USC were characterised by cell surface marker expression profile and multipotent differentiation. The in vitro immunomodulatory effect of USC was evaluated by co-culturing with human CD4+ T cells upon stimulation with phytohaemagglutinin [PHA]. The proliferation of CD4+ T was measured by fluorescence-activated cell sorting [FACS]. Cytokine array and quantitative real-time polymerase chain reaction [RT-PCR] were applied to examine cytokine levels. In vivo therapeutic value of USC was assessed using a murine colitis model induced by dextran sulphate sodium [DSS] or 2, 4, 6-trinitrobenzene sulphonic acid [TNBS]. The immunomodulatory effect of USC and bone marrow-derived mesenchymal stem cells [BMSC] was compared when co-cultured with CD4+ T cells. The therapeutic efficacy of USC and BMSC on IBD was compared when administered in an acute DSS model in vivo.

RESULTS

USC were positive for mesenchymal stem cell markers but were negative for haematopoietic stem cell markers. These cells differentiated into osteo-, adipo-, and chondrogenic cell lineages. Similar to BMSC, the proliferation of CD4+ T cells was significantly inhibited when co-cultured with USC, as a consequence of Th1/Th17 immune response inhibition. Systemic administration of USC significantly ameliorated the clinical and histopathological severity of colitis and increased the survival rate in both acute and chronic murine colitis models. Moreover, implantation of USC led to downregulation of the Th1/Th17 immune responses in a PGE2-dependent manner.

CONCLUSIONS

This study demonstrated that implantation of USC reduces inflammation in an IBD rodent model via downregulation of Th1/Th17 immune responses, indicating that USC therapy serves as a potential cell-based therapeutic candidate treatment for IBD.

Preclinical Study in Vivo for New Pharmacological Approaches in Inflammatory Bowel Disease: A Systematic Review of Chronic Model of TNBS-Induced Colitis

The preclinical studies in vivo provide means of characterizing physiologic interactions when our understanding of such processes is insufficient to allow replacement with in vitro systems and play a pivotal role in the development of a novel therapeutic drug cure. Chemically induced colitis models are relatively easy and rapid to develop. The 2,4,6-trinitrobenzenesulfonic acid (TNBS) colitis model is one of the main models in the experimental studies of inflammatory bowel disease (IBD) since inflammation induced by TNBS mimics several features of Crohn’s disease. This review aims to summarize the existing literature and discuss different protocols for the induction of chronic model of TNBS-induced colitis. We searched MEDLINE via Pubmed platform for studies published through December 2018, using MeSH terms (Crohn Disease.kw) OR (Inflammatory Bowel Diseases.kw) OR (Colitis, Ulcerative.kw) AND (trinitrobenzenesulfonic acid.kw) AND (disease models, animal.kw) AND (mice.all). The inclusion criteria were original articles, preclinical studies in vivo using mice, chronic model of colitis, and TNBS as the inducer of colitis and articles published in English. Chronic TNBS-induced colitis is made with multiple TNBS intrarectal administrations in an average dose of 1.2 mg using a volume lower than 150 μL in 50% ethanol. The strains mostly used are Balb/c and C57BL/6 with 5–6 weeks. To characterize the preclinical model the parameters more used include body weight, stool consistency and morbidity, inflammatory biomarkers like interferon (IFN)-γ, myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10, presence of ulcers, thickness or hyperemia in the colon, and histological evaluation of the inflammation. Experimental chronic colitis is induced by multiple rectal instillations of TNBS increasing doses in ethanol using Balb/c and C57BL/6 mice.

Total flavone of Abelmoschus manihot ameliorates Crohn's disease by regulating the NF‑κB and MAPK signaling pathways

Crohn's disease (CD) is a chronic relapsing form of inflammatory bowel disease, and its pathogenesis remains unknown. Total flavone of Abelmoschus manihot L. Medic (TFA), has been used as anti‑inflammatory and myocardial ischemia protective drug. The present study aimed to explore the effects of TFA on CD and its underlying mechanism. We reported that TFA comprises eight flavone glycosides, including quercetin‑3‑O‑robinobioside, gossypetin‑3‑O‑glucoside, quercetin‑3'‑O‑glucoside, isoquercetin, hyperoside, myricetin, gossypetin and quercetin. In vivo, TFA promoted the survival of 2,4,6‑trinitrobenzene sulfonic acid (TNBS)‑induced colitis in mice, decreased weight loss and increased colon length in a dose‑dependent manner. Additionally, TFA notably ameliorated the inflammatory response in mice with TNBS‑induced colitis as determined by histopathological analysis. In addition, the administration of TFA in mice with TNBS‑induced colitis led to a significant decrease in the levels of cytokines in the sera and colon tissues; a significant decrease myeloperoxidase activity in the colon tissues was also observed. These findings may be associated with the suppression of the nuclear factor‑κB (NF‑κB) and mitogen‑activated protein kinase (MAPK) signaling pathways. In vitro, TFA significantly downregulated the expression of cytokines in lipopolysaccharide (LPS)‑induced RAW264.7 cells. In addition, TFA suppressed LPS‑induced activation of the NF‑κB and MAPK signaling pathways in RAW264.7 cells. Our findings indicated that TFA could suppress the inflammatory response in mice with TNBS‑induced colitis via inhibition of the NF‑κB and MAPK signaling pathways. The results of the present study may improve understanding of the function of TFA and provide a novel theoretical basis for the treatment of CD.

Perspectives of the International Society for Cell & Gene Therapy Gastrointestinal Scientific Committee on the Intravenous Use of Mesenchymal Stromal Cells in Inflammatory Bowel Disease (PeMeGi)

Inflammatory bowel disease (IBD), namely, Crohn's disease and ulcerative colitis, remains a grievous and recalcitrant problem incurring significant human and health care costs, even in consideration of the growing incidence. Initial goals of care aimed to achieve the induction and maintenance of clinical remission. The advent of novel treat-to-target approaches using patient stratification, early introduction of immunosuppressants and rapid escalation to biologics or early use of combination therapy has refocused the goals of care toward the achievement of mucosal healing. This is in an attempt to preserve intestinal function, decrease hospitalization and surgery rates and improve the quality of life of affected patients. Cellular therapeutics for the treatment of IBD offers an unprecedented opportunity to change the current paradigm from single-targeted to systems-targeted therapy, trying to dampen the whole inflammatory cascade instead of a only molecule. Therefore, as we move forward, the importance of designing informative and possibly adaptive trial designs, standardizing methodologies, harmonizing goals of therapy and evaluating methods cannot be underemphasized. In this article, we review the current literature on the application of mesenchymal stromal cells for the treatment of IBD in an effort to establish a consensus on designing efficient and consistent clinical trials for the intravenous use of this cellular therapy in IBD.

Role of interventional inflammatory bowel disease in the era of biologic therapy: a position statement from the Global Interventional IBD Group

Interventional (or therapeutic) inflammatory bowel disease (IBD) endoscopy has an expanding role in the treatment of disease and surgical adverse events. Endoscopic therapy has been explored and used in the management of strictures, fistulas/abscesses, colitis-associated neoplasia, postsurgical acute or chronic leaks, and obstructions. The endoscopic therapeutic modalities include balloon dilation, stricturotomy, stent placement, fistulotomy, fistula injection and clipping, sinusotomy, EMR, and endoscopic submucosal dissection. With a better understanding of the disease course of IBD, improved long-term impact of medical therapy, and advances in endoscopic technology, we can foresee interventional IBD becoming an integrated part of the multidisciplinary approach to patients with complex IBD.