Optimization of conventional therapy in patients with IBD

Saffron as a Promising Therapy for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory illness of the gastrointestinal tract (GI), characterized by recurrent episodes of inflammation and tissue destruction. It affects an increasing number of individuals worldwide who suffer from Crohn's disease (CD) or ulcerative colitis (UC). Despite substantial advances in understanding the underlying causes of IBD, the available treatments remain restricted and are sometimes accompanied by severe consequences. Consequently, there is an urgent need to study alternate therapeutic options. This review assesses the present drugs, identifies their limitations, and proposes the use of saffron, a natural plant with great therapeutic potential based on preclinical and clinical investigations. Saffron has gained attention for its potential therapeutic benefits in treating various ailments due to its established bioactive compounds possessing antioxidant and anti-inflammatory properties. This review covers how saffron impacts the levels of calprotectin, an inflammatory marker, for various inflammatory responses in multiple diseases including IBD. Data from clinical trials were assessed to determine the efficacy and safety of using saffron to counter inflammation in multiple diseases. Studies have shown that saffron may protect against inflammatory bowel disease (IBD) through several mechanisms by inhibiting pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), reducing oxidative stress through antioxidant effects, enhancing mucosal barrier function by upregulating tight junction proteins, and modulating the gut microbiota composition to promote beneficial bacteria while suppressing pathogenic ones; these combined actions contribute to its therapeutic potential in managing and alleviating the symptoms of IBD. This will enable future research endeavors and expedite the translation of saffron-based interventions into clinical practice as a valuable adjunctive therapy or a potential alternative to conventional treatments, thereby enhancing the quality of life for individuals suffering from inflammatory diseases including IBD.

One-Year Clinical Outcomes of Subcutaneous Infliximab Maintenance Therapy Compared With Intravenous Infliximab Maintenance Therapy in Patients With Inflammatory Bowel Disease: A Prospective Cohort Study

BACKGROUND

Although the pharmacokinetic profile of subcutaneous (SC) infliximab (IFX) is superior to conventional intravenous (IV) IFX, long-term efficacy and safety of SC IFX in patients with inflammatory bowel disease (IBD) have not been reported yet. This study aimed to evaluate long-term clinical outcomes of IBD patients treated with SC IFX compared with those of IBD patients treated with IV IFX during maintenance therapy.

METHODS

This prospective cohort study enrolled 61 IBD patients in clinical remission who received scheduled IFX maintenance therapy. Of them, 38 patients were switched to SC IFX, while 23 patients continued IV IFX with dose optimization. Enrolled patients were followed up for 1 year. The primary outcome was durable remission defined as clinical remission (Crohn's disease, Harvey-Bradshaw index <5; ulcerative colitis, partial Mayo score <2) and biochemical remission (C-reactive protein <0.5 mg/dL) with IFX trough level ≥3 µg/mL throughout the follow-up period.

RESULTS

One-year clinical remission, 1-year biochemical remission, and mucosal healing did not differ between the IV and SC IFX groups (n = 20 of 23 vs 33 of 38; P = 1.000; n = 22 of 23 vs 34 of 38; P = .641; and n = 10 of 18 vs 17 of 25; P = .414, respectively). During follow-up, the number of patients with IFX trough level <3 μg/mL was significantly lower in the SC IFX group (n = 0 of 38, 0%) than in the IV IFX group (n = 10 of 23, 43%) (P < .001). The SC IFX group showed higher 1-year durable remission than the IV IFX group (n = 31 of 38, 82% vs n = 11 of 23, 48%; P = .013). The incidence of IFX-related adverse events did not differ significantly between both groups (26% vs 39%; P = .446).

CONCLUSION

The SC IFX switch induced a higher 1-year durable remission rate than continuing IV IFX in patients with IBD during scheduled maintenance therapy, showing similar safety.

Chicoric Acid Effectively Mitigated Dextran Sulfate Sodium (DSS)-Induced Colitis in BALB/c Mice by Modulating the Gut Microbiota and Fecal Metabolites

Chicoric acid (CA) has been reported to exhibit biological activities; it remains unclear, however, whether CA could regulate colitis via modulation of the gut microbiota and metabolites. This study aimed to assess CA's impact on dextran sulfate sodium (DSS)-induced colitis, the gut microbiota, and metabolites. Mice were induced with 2.5% DSS to develop colitis over a 7-day period. CA was administered intragastrically one week prior to DSS treatment and continued for 14 days. The microbial composition in the stool was determined using 16S rRNA sequencing, while non-targeted metabolomics was employed to analyze the metabolic profiles of each mouse group. The results show that CA effectively alleviated colitis, as evidenced by an increased colon length, lowered disease activity index (DAI) and histological scores, and decreased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) expression levels. CA intervention restored the structure of gut microbiota. Specifically, it decreased the abundance of Bacteroidetes and Cyanobacteria at the phylum level and Bacteroides, Rosiarcus, and unclassified Xanthobacteraceae at the genus level, and increased the abundance of unclassified Lachnospiraceae at the genus level. Metabolomic analysis revealed that CA supplementation reversed the up-regulation of asymmetric dimethylarginine, N-glycolylneuraminic acid, and N-acetylneuraminic acid, as well as the down-regulation of phloroglucinol, thiamine, 4-methyl-5-thiazoleethanol, lithocholic acid, and oxymatrine induced by DSS. Our current research provides scientific evidence for developing CA into an anti-colitis functional food ingredient. Further clinical trials are warranted to elucidate the efficacy and mechanism of CA in treating human inflammatory bowel disease (IBD).

Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study

AIM

This study was aimed at evaluating the effect of acetyl-11-keto-β-boswellic acid (AKBA) on dental pulp stem cells (DPSCs) viability and proliferation to be used as a potential root canal medicament.

MATERIALS AND METHODS

Dental pulp stem cells were isolated from human third molars. The phenotypic characterization of DPSCs was verified by flow cytometry analysis. The viability assay was performed using the methyl-thiazoltetrazolium (MTT) assay. Cells were treated with different concentration of triple antibiotic paste (TAP) and calcium hydroxide Ca(OH2) (5, 2.5, 1, 0.5, and 0.25 mg/mL), AKBA (10, 5, 1, 0.1, and 0.01 µM). All experiments were done in separate triplicate experiments. Results: Dental pulp stem cells were characterized by flow cytometry. Cells treated with Ca(OH)2 (1, 2.5, and 5 mg/mL) showed significantly reduced viability compared with the control cells (p < 0.05). Dental pulp stem cells treated with 1, 2.5, and 5 mg/mL TAP resulted in a significant decrease in viability (p < 0.05). Cells treated with AKBA in concentrations (1, 0.1, and 0.01 µM) demonstrated higher viability than the control group (p < 0.05), while AKBA in concentrations (5 and 10 µM) showed equal or decreased viability than the control group. (p > 0.05). Regarding cell density assay, AKBA showed significant increase in cell density after 5 and 7 days compared with cells medicated with TAP and Ca(OH)2 while TAP revealed marked reduction in cell density in all the tested intervals.

CONCLUSION

Acetyl-11-keto-β-boswellic acid in lower concentrations (0.01, 0.1, and 1 µM) demonstrated superior cell viability than TAP and Ca(OH)2, and it may possess the potential to be an intracanal medicament in regenerative endodontics.

CLINICAL SIGNIFICANCE

Studying the effect of different potential root canal medicaments and their capability to induce DPSCs proliferation might be of value. The influence of AKBA on the viability and proliferation of DPSCs tested in this study sheds light on its use as a potential intracanal medication especially in regenerative endodontics. How to cite this article: Amer NA, Badawi MF, Elbeltagi MG, et al. Effect of Boswellic Acid on Viability of Dental Pulp Stem Cells Compared to the Commonly Used Intracanal Medications: An In Vitro Study. J Contemp Dent Pract 2023;24(12):957-966.

The PERFUSE study: The experience of patients receiving Adalimumab biosimilar SB5

BACKGROUND

SB5 is an EMA-approved adalimumab biosimilar, having demonstrated bioequivalence, equivalent efficacy, and similar safety and immunogenicity to the reference product.

AIMS

Describe patient training and satisfaction using patient-reported outcome measures (PROMs) and assess their impact on 12-month persistence on SB5.

METHODS

The observational PERFUSE study included 318 Crohn's disease (CD) patients and 88 ulcerative colitis (UC) patients in 27 sites across France between October 2018 and December 2020. PROMs were collected at 1-month post-baseline using an online questionnaire (ePRO) designed with patient associations. Treatment persistence was collected during routine visits (up to 15 months post-initiation). Results are presented by prior experience with subcutaneous biologics and training in proper use of the injection device.

RESULTS

57.1% (n = 145) and 44.1% (n = 67) of naïve and pre-treated patients, respectively, answered the ePRO. Naïve patients were offered training more often (86.9% vs 31.3% respectively, p < 0.05), with disparities between sites. All subgroups' satisfaction scores were high. 12-month persistence on SB5 was significantly higher for respondents than for non-respondents (68.0% [60.9; 74.1] vs 52.3% [44.5; 59.6]; p < 0.05) and in patients with a better perception of their illness (OR=1.02, [1.0; 1.05]; p < 0.05).

CONCLUSIONS

Early patient questionnaires may be useful to identify patients at higher risk of treatment discontinuation.

Recent advances on emerging nanomaterials for diagnosis and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic idiopathic inflammatory disorder that affects the entire gastrointestinal tract and is associated with an increased risk of colorectal cancer. Mainstream clinical testing methods are time-consuming, painful for patients, and insufficiently sensitive to detect early symptoms. Currently, there is no definitive cure for IBD, and frequent doses of medications with potentially severe side effects may affect patient response. In recent years, nanomaterials have demonstrated considerable potential for IBD management due to their diverse structures, composition, and physical and chemical properties. In this review, we provide an overview of the advances in nanomaterial-based diagnosis and treatment of IBD in recent five years. Multi-functional bio-nano platforms, including contrast agents, near-infrared (NIR) fluorescent probes, and bioactive substance detection agents have been developed for IBD diagnosis. Based on a series of pathogenic characteristics of IBD, the therapeutic strategies of antioxidant, anti-inflammatory, and intestinal microbiome regulation of IBD based on nanomaterials are systematically introduced. Finally, the future challenges and prospects in this field are presented to facilitate the development of diagnosis and treatment of IBD.

Aurozyme: A Revolutionary Nanozyme in Colitis, Switching Peroxidase-Like to Catalase-Like Activity

A therapeutic strategy that could address colitis of multiple etiologies while restoring the dysbiosis of gut microbiota is attractive. Here, Aurozyme, a novel nanomedicine comprised of gold nanoparticles (AuNPs) and glycyrrhizin (GL) with a glycol chitosan coating layer, as a promising approach for colitis, is demonstrated. The unique feature of Aurozyme is the conversion of harmful peroxidase-like activity of AuNPs to beneficial catalase-like activity due to the amine-rich environment provided by the glycol chitosan. This conversion process enables Aurozyme to oxidize the hydroxyl radicals derived from AuNP, producing water and oxygen molecules. In fact, Aurozyme effectively scavenges reactive oxygen/reactive nitrogen species (ROS/RNS) and damage-associated molecular patterns (DAMPs), which can attenuate the M1 polarization of macrophage. It exhibits prolonged adhesion to the lesion site, promoting sustained anti-inflammatory effects and restoring intestinal function in colitis-challenged mice. Additionally, it increases the abundance and diversity of beneficial probiotics, which are essential for maintaining microbial homeostasis in the gut. The work highlights the transformative potential of nanozymes for the comprehensive treatment of inflammatory disease and represents an innovative switching technology of enzyme-like activity by Aurozyme.

Atmosphere-inspired multilayered nanoarmor with modulable protection and delivery of Interleukin-4 for inflammatory microenvironment modulation

Inflammatory bowel disease (IBD) has been closely associated with immune disorders and excessive M1 macrophage activation, which can be reversed by the M2-polarizing effect of interleukin-4 (IL-4). However, maintaining native IL-4 activity with its specific release in the inflammatory microenvironment and efficient biological performance remain a challenge. Inspired by the multilayered defense mechanism of the earth's atmosphere, we constructed a multilayered protective nanoarmor (NA) for IL-4 delivery (termed as IL-4@PEGRA NAs) into an intricate inflammatory microenvironment. The poly(ethylene glycol) (PEG)-ylated phenolic rosmarinic acid (RA)-grafted copolymer contains two protective layers-the intermediate polyphenol (RA molecules) and outermost shield (PEG) layers-to protect the biological activity of IL-4 and prolong its circulation in blood. Moreover, IL-4@PEGRA NAs scavenge reactive oxygen species with the specific release of IL-4 and maximize its biofunction at the site of inflammation, leading to M2 macrophage polarization and downregulation of inflammatory mediators. Simultaneously, gut microbiota dysbiosis can improve to amplify the M2-polarizing effect and inhibit the phosphatidylinositol 3 kinase/Akt signaling pathway, thereby attenuating inflammation and promoting colitis tissue repair. It provides a nature-inspired strategy for constructing an advanced multilayered NA delivery system with protective characteristics and potential for IBD management.

Exploring the Targets and Molecular Mechanisms of Thalidomide in the Treatment of Ulcerative Colitis: Network Pharmacology and Experimental Validation

BACKGROUND

Ulcerative colitis (UC) is a chronic, nonspecific, inflammatory disease of the intestine with an unknown cause. Thalidomide (THA) has been shown to be an effective drug for the treatment of UC. However, the molecular targets and mechanism of action of THA for the treatment of UC are not yet clear.

OBJECTIVES

Combining network pharmacology with in vitro experiments, this study aimed to investigate the potential targets and molecular mechanisms of THA for the treatment of UC.

METHODS

Firstly, relevant targets of THA against UC were obtained from public databases. Then, the top 10 hub targets and key molecular mechanisms of THA for UC were screened based on the network pharmacology approach and bioinformatics method. Finally, an in vitro cellular inflammation model was constructed using lipopolysaccharide (LPS) induced intestinal epithelial cells (NCM460) to validate the top 10 hub targets and key signaling pathways.

RESULTS

A total of 121 relevant targets of THA against UC were obtained, of which the top 10 hub targets were SRC, LCK, MAPK1, HSP90AA1, EGFR, HRAS, JAK2, RAC1, STAT1, and MAP2K1. The PI3K-Akt pathway was significantly associated with THA treatment of UC. In vitro experiments revealed that THA treatment reversed the expression of HSP90AA1, EGFR, STAT1, and JAK2 differential genes. THA was able to up- regulate the mRNA expression of pro-inflammatory factor IL-10 and decrease the mRNA levels of anti-inflammatory factors IL-6, IL-1β, and TNF-α. Furthermore, THA also exerted anti-inflammatory effects by inhibiting the activation of the PI3K/Akt pathway.

CONCLUSION

THA may play a therapeutic role in UC by inhibiting the PI3K-Akt pathway. HSP90AA1, EGFR, STAT1, and JAK2 may be the most relevant potential therapeutic targets for THA in the treatment of UC.

Colon-Targeted Trans-Cinnamic Acid Ameliorates Rat Colitis by Activating GPR109A

We designed colon-targeted trans-cinnamic acid (tCA) and synthesized its conjugates with glutamic acid (tCA-GA) and aspartic acid (tCA-AA). We evaluated the anti-colitic activity of colon-targeted tCA using a dinitrobenzenesulfonic acid-induced rat colitis model. The conjugates lowered the distribution coefficient and Caco-2 cell permeability of tCA and converted to tCA in the cecum, with higher rates and percentages with tCA-GA than with tCA-AA. Following oral gavage, tCA-GA delivered a higher amount of tCA to the cecum and exhibited better anti-colitic effects than tCA and sulfasalazine (SSZ), which is the current treatment for inflammatory bowel disease. In the cellular assay, tCA acted as a full agonist of GPR109A (EC50: 530 µM). The anti-colitic effects of tCA-GA were significantly compromised by the co-administration of the GPR109A antagonist, mepenzolate. Collectively, colon-targeted tCA potentiated the anti-colitic activity of tCA by effectively activating GPR109A in the inflamed colon, enabling tCA to elicit therapeutic superiority over SSZ.

Bioadhesive Tannic-Acid-Functionalized Zein Coating Achieves Engineered Colonic Delivery of IBD Therapeutics via Reservoir Microdevices

The biggest challenge in oral delivery of anti-inflammatory drugs such as 5-aminosalicylic acid (5-ASA) is to (i) prevent rapid absorption in the small intestine and (ii) achieve localized release at the site of inflammation in the lower gut, i.e., the colon. Here, we present an advanced biopolymeric coating comprising of tannic-acid-functionalized zein protein to provide a sustained, colon-targeted release profile for 5-ASA and enhance the mucoadhesion of the dosage form via a mussel-inspired mechanism. To enable localized delivery and provide high local concentration, 5-ASA is loaded into the microfabricated drug carriers (microcontainers) and sealed with the developed coating. The functionality and drug release profile of the coating are characterized and optimized in vitro, showing great tunability, scalability, and stability toward proteases. Further, ex vivo experiments demonstrate that the tannic acid functionalization can significantly enhance the mucoadhesion of the coating, which is followed up by in vivo investigations on the intestinal retention, and pharmacokinetic evaluation of the 5-ASA delivery system. Results indicate that the developed coating can provide prolonged colonic delivery of 5-ASA. Therefore, the here-developed biodegradable coating can be an eco-friendly substitute to the state-of-the-art commercial counterparts for targeted delivery of 5-ASA and other small molecule drugs.

Indicators of Suboptimal Treatment and Associated Healthcare Costs Among Patients With Crohn's Disease Initiated on Biologic or Conventional Agents

Background

As the treatment landscape for Crohn's disease (CD) evolves, an up-to-date understanding of the burden associated with indicators of suboptimal treatment is needed. The aim of this study was to describe suboptimal treatment indicators and associated healthcare costs among CD patients initiated on a biologic or conventional agent.

Methods

Adults with CD were identified in a US healthcare claims database (Optum's Clinformatics Data Mart; 01/2004-03/2019). The first biologic or conventional agent claim within 12 months of a CD diagnosis was the index date/agent. Indicators of suboptimal treatment (nonadherence, dose escalation, chronic corticosteroid use, augmentation, ≥1 CD surgery, ≥2 CD emergency department visits, ≥1 CD inpatient (IP) stay, switch, cycling, restart, inadequate induction) were identified in the 12-month postindex landmark period. The mean per-patient-per-year (PPPY) healthcare costs (2019 USD) were evaluated in the year postlandmark.

Results

There were 5107 patients (mean age ~44 years, 56% female) in the biologic and 6072 patients (~51 years; 59% female) in the conventional cohort. In the biologic cohort, 79.4% of patients had ≥1 suboptimal treatment indicator. Mean PPPY healthcare costs increased with the number of suboptimal treatment indicators, from $46 100 (no indicator) to $68 572 (≥4 indicators). The conventional cohort had similar patterns: 72.5% of patients presented ≥1 suboptimal treatment indicator, and mean PPPY healthcare costs increased from $17 329 (no indicator) to $67 568 (≥4 indicators). In both cohorts, IP and outpatient medical costs (excluding biologics) contributed a major portion of the increase.

Conclusions

Among CD patients, suboptimal treatment indicators were common and were associated with an increased burden to the healthcare system.

Emerging role of biosimilars in the clinical care of inflammatory bowel disease patients

The increasing incidence of inflammatory bowel disease (IBD) globally has redirected the healthcare system's focus towards safe and affordable pharmacological interventions. The inception of anti-tumor necrosis factor-α (TNF-α) had resulted in a trend shift from surgical interventions. However, as the patents of approved anti-TNF-α drugs expire, biological copies of the many approved products are in the pipeline. The most commonly used biosimilar for IBD has been infliximab, followed by Adalimumab biosimilars which have been approved in major countries across the world. Although biosimilars are approved on the basis of similarity of their reference product, the lack of real-world evidence of its safety in ulcerative colitis and Crohn’s disease patients has contributed to physicians’ hesitancy. However, biosimilars are expected to reduce treatment costs and provide economic benefits.

Optimizing Therapies Using Therapeutic Drug Monitoring: Current Strategies and Future Perspectives

Therapeutic drug monitoring (TDM) has emerged as a strategy for treatment optimization in inflammatory bowel diseases to maximize benefit and to reach more stringent, objective end points. Optimal drug concentrations in inflammatory bowel disease vary according to treatment target, disease phenotype, inflammatory burden, and timing of sampling during the treatment cycle. This review provides an update on TDM with biologic and oral small molecules, evaluates the role of reactive vs proactive TDM, and identifies the gaps in current evidence. In the future, adaptations to how we use TDM may contribute further to the goal of personalized treatment in patients with IBD.

A nanoparticulate dual scavenger for targeted therapy of inflammatory bowel disease

A therapeutic strategy that targets multiple proinflammatory factors in inflammatory bowel disease (IBD) with minimal systemic side effects would be attractive. Here, we develop a drug-free, biodegradable nanomedicine that acts against IBD by scavenging proinflammatory cell-free DNA (cfDNA) and reactive oxygen species (ROS). Polyethylenimine (PEI) was conjugated to antioxidative diselenide-bridged mesoporous organosilica nanoparticles (MONs) to formulate nanoparticles (MON-PEI) that exhibited high cfDNA binding affinity and ROS-responsive degradation. In ulcerative colitis and Crohn's disease mouse colitis models, orally administered MON-PEI accumulated preferentially in the inflamed colon and attenuated colonic and peritoneal inflammation by alleviating cfDNA- and ROS-mediated inflammatory responses, allowing a reduced dose frequency and ameliorating colitis even after delayed treatment. This work suggests a new nanomedicine strategy for IBD treatment.

Recommendations for the optimal use of mesalazine in the management of patients with mild to moderate ulcerative colitis

The 2021 National report from IBD UK included responses from over 10 000 patients with inflammatory bowel disease, over 70% of whom reported having at least one flare in the last 12 months. As the first-line treatment for patients with mild and moderate ulcerative colitis, the action and delivery mechanisms of mesalazine are crucial for successful management of the disease. The choice of the most appropriate formulation of mesalazine and securing patient concordance and adherence to treatment remains a challenge for healthcare professionals. This article details the outcome of a roundtable discussion involving a group of gastroenterology consultants and specialist nurses which considered the importance of ensuring that patients have individualised mesalazine therapy before escalation to other treatments and gives recommendations for the management of patients with mild or moderate ulcerative colitis.

Beneficial role of Pistacia lentiscus aqueous extract in experimental colitis: anti-inflammatory and potential therapeutic effects

BACKGROUND

Pistacia lentiscus L. (PL) is a flowering plant traditionally used in the treatment of gastrointestinal disorders. The extracts of this plant are endowed with strong pharmacological activities. The aim of our current study was to investigate the anti-inflammatory and potential therapeutic effects of PL leaves aqueous extract (PLAE) against Dextran Sulfate Sodium (DSS)-induced acute colitis.

MATERIALS AND METHODS

The therapeutic effect of PLAE was evaluated after orally administration of 3% DSS alone or concomitantly with PLAE (50, 100 or 200 mg/Kg). Mucosal lesions were assessed by macroscopic and histopathological examination. In this context, hemorrhage, diarrhea, weight loss, and disease activity index (DAI) were determined daily throughout the experiment. In the same way, hematoxylin-eosin and Alcian blue staining of colonic mucosal were used to evaluate, respectively, mucosal damages and mucus production. Furthermore, the levels of nitric oxide (NO), and pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] were measured in plasma, as well as in colonic explants and peritoneal macrophages cultures supernatants.

RESULTS

Administration of DSS + PLAE indicated a significant reduction in clinical score of acute colitis DAI compared to DSS alone administration. Interestingly, histological analysis of the mucosa showed that DSS + PLAE-treated groups exhibited almost normal histology evidenced by an intact epithelium structure and less inflammatory cell infiltration in the mucosa. Alcian bleu staining revealed that DSS + PLAE-treated groups displayed almost normal mucus production. Importantly, a significant decrease in pro-inflammatory mediators (NO, IL-6 and TNF-α) levels in dose-dependent manner was reported in plasma, and culture supernatants of colonic explants and peritoneal macrophages from DSS + PLAE-treated mice compared to the DSS group.

CONCLUSION

Our results showed that the systemic and local anti-inflammatory activities of aqueous leaves extract of PL improve the clinical signs of acute colitis. Our data suggest that PLAE has beneficial effects and could constitute a promising approach against acute ulcerative colitis by targeting the deregulated immune response.

Nanoparticle-mediated gene therapy strategies for mitigating inflammatory bowel disease

Inflammatory bowel disease (IBD) is an autoimmune disorder of the gastrointestinal tract (GIT) where Ulcerative Colitis (UC) displays localized inflammation in the colon, and Crohn's Disease (CD) affects the entire GIT. Failure of current therapies and associated side-effects bring forth serious social, economic, and health challenges. The gut epithelium provides the best target for gene therapy delivery vehicles to combat IBD. Gene therapy involving the use of nucleic acid (NA) therapeutics faces major challenges due to the hydrophilic, negative-charge, and degradable nature of NAs. Recent success in the engineering of biomaterials for gene therapy and their emergence in clinical trials for various diseases is an inspiration for scientists to develop gene therapy vehicles that can be easily targeted to the desired tissues for IBD. Advances in nanotechnology have enabled the formulations of numerous nanoparticles for NA delivery to mitigate IBD that still faces challenges of stability in the GIT, poor therapeutic efficacy, and targetability. This review presents the challenges of gene therapeutics, gastrointestinal barriers, and recent advances in the engineering of nanoparticles for IBD treatment along with future directions for successful translation of nanoparticle-mediated gene therapeutics in clinics.

Recent Progress in the Diagnosis and Precise Nanocarrier-Mediated Therapy of Inflammatory Bowel Disease

The effective colon drug delivery remains to be an international frontier research in inflammatory bowel disease (IBD) therapy. The exploration and research of nanocarrier-based nanomedicine with great potential brings new opportunities for IBD therapy and diagnoses. Functional nanocarriers with varying morphology and characteristics can not only effectively avoid the destruction of the complex gastrointestinal (GI) tract microenvironment but also endow drugs with target therapy and improved bioavailability, thus elevating therapeutic efficacy. In this review, we illustrated several challenges in IBD therapy, then emphasis on some latest research progress of nanoparticles based therapy of oral administration, rectal administration and parenteral administration, as well as IBD diagnoses. Finally, we described the future perspective of nanocarriers in the treatment and diagnoses of IBD.

Preparation, characterization, and in vitro drug release behavior of thiolated alginate nanoparticles loaded budesonide as a potential drug delivery system toward inflammatory bowel diseases

For site-specific drug delivery in inflammatory bowel disease, reducible sodium alginate nanoparticles cross-linked with disulfide linkage were developed. Nanoparticles were synthesized in deionized water through self-assembly of amphiphilic thiolated sodium alginate Alg-Cys and subsequently produced cross-linking of disulfide bonds. TEM image showed a spherical core-shell configuration with a size of about 430 nm for the nanoparticles. Dynamic light scattering (DLS) showed high stability, narrow size distribution, and pH-dependent swelling transition for the nanoparticles. Cytotoxicity study showed that there was no evident cell inhibition among the nanoparticles. Also, the size of the nanoparticles increased in 10 mM glutathione (GSH) solution due to the cleavage of disulfides within their network structures. Compared to that in GSH-free buffer, there was a remarkable increase in drug release in pH 7.4 buffer with GSH from drug-loaded nanoparticles, indicating that the nanoparticles could be used for colon-specific drug delivery.

Beneficial effect of Bidens pilosa L. (Asteraceae) in a rat model of colitis

Background Bidens pilosa (BP) possessed anti-inflammatory, antioxidant, and immunomodulatory activities. Its beneficial effects on intestinal inflammation and oxidative stress in 2,4,6 trinitrobenzene sulfonic acid (TNBS) induced colitis in Wistar rats was evaluated. Methods Thirty female Wistar rats weighing 180-200 g were distributed into six groups (n = 5): non-colitic, untreated colitic and colitic rats treated graded doses of methanol extract of BP (50-400 mg/kg). Colitis was induced in rats by intracolonic instillation of 0.2 mL of 40 mg/mL TNBS. BP was administered two days pre-colitis induction and treatments continued until seven days post-colitis induction. A day after the last treatment, rats were euthanized, colon removed aseptically and response to treatment assessed. Phytochemical composition of BP was determined using the GC-MS. Results BP significantly reduced macroscopic colonic damage score, weight/length ratio, colonic lipid peroxidation level, leukocytes infiltration, and TNF-α level in comparison to untreated colitic rats (p ≤ 0.008). Similarly, treatment with 200 and 400 mg/kg BP prevented depletion of colonic glutathione level than other treatment groups (p ≤ 0.0002). Histological findings revealed that treatment with 400 mg/kg BP significantly preserved the mucosal epithelial layer. It also prevented ulceration and sloughing of the mucosal layers and reduced infiltration of inflammatory cells compared to other treatment groups. Among the 16 compounds identified were oleic acid (6.2%) and n-hexadecanoic acid (2.0%) with antioxidant anti-inflammatory activities. Conclusions The beneficial effects of BP in rat colitis might be related to the reduction of leucocytes infiltration, inhibition of oxidative stress and pro-inflammatory cytokines.

Current Status of M1 and M2 Macrophages Pathway as Drug Targets for Inflammatory Bowel Disease

Chronic inflammation of the gastrointestinal system is mediated by both the immune system activity and homeostasis, mainly through releasing of various cytokines and chemokines, as well as the transmigration of the inflammatory cells to the affected site. In between, macrophages are key mediators of the immune system, nearly located all over the gastrointestinal tract. Macrophages have vital influence on the inflammatory condition with both pro-inflammatory and anti-inflammatory functions. Their polarization status has been linked to numerous metabolic disorders such as inflammatory bowel disease (IBD). The equilibrium between the phenotypes and functions of inflammatory M1 and anti-inflammatory M2 cells is regulated by both extracellular and intracellular stimuli, determining how the disease progresses. Thereby, factors that interchange such balance in the direction of increasing M2 macrophages offer unique approaches for future management of IBD. This study reflects the novel IBD treatment targets via the immune system's pathway, reporting the latest treatments that regulate the M1/M2 macrophages distribution in a way to favor IBD.

Desirability Based Optimization of New Mesalazine Modified Release Formulations: Compression Coated Tablets and Mini Tablets in Capsules

Background:

Mesalazine (5-aminosalicylic acid, 5-ASA) is a drug substance with an antiinflammatory activity, which is mainly used in the symptomatic treatment of diseases, such as Ulcerative Colitis, the Crohn's disease and the idiopathic inflammatory bowel disease. Mesalazine exerts its effect locally in the inflamed area of the intestine and not through systematic absorption, therefore the investigation of its release characteristics from solid pharmaceutical formulations is of great importance.

Objective:

The development of novel mesalazine modified release formulations with improved properties, regarding drug release in the gastrointestinal tract, by utilisation of the Design of Experiments (DoE) approach.

Methods:

D-optimal experimental design was applied. A Simplex Lattice mixture design was used for the development of suitable capsules containing 4 mini tablets and a D-optimal mixture design was used for compression-coated tablets, with the following characteristics: ≤10% release in 2 h, to minimize its degradation in the upper gastrointestinal tract, 20-40% release in 5 h for mesalazine administration in the small intestine, and quantitative release in 12 h for colonic delivery. The dissolution experiments were conducted in gastrointestinal-like fluids and pectinases to simulate the pectinolytic enzymes present in the colon.

Results:

The optimal compositions were reached via the desirability function, as a compromise to the different responses. The optimal solutions for both formulations led to colon-specific delivery of the active substance with minimal 5-ASA release in the upper gastrointestinal tract and appeared to conform with the pre-determined characteristics. Hard gelatin capsules, when filled with mini-tablets led to the aimed modified release profile, having sigmoidal characteristics and compression coated tablets led to colonic delivery.

Conclusion:

Two novel mesalazine formulations were developed with the desirable colonic release, by conducting a minimal number of experiments, as suggested by DoE experimental design.

An In Situ Gelling System for the Local Treatment of Inflammatory Bowel Disease (IBD). The Loading of Maqui (Aristotelia Chilensis) Berry Extract as an Antioxidant and Anti-Inflammatory Agent

The aim of the present work was the development of an innovative in situ gelling system, to be applied on the mucosa of the distal colon via rectal route. The system consisted of three polymers having different functions: gellan (GG), able to jellify in presence of ions; methylcellulose (MC), a thermosensitive polymer with a gelation temperature close to 50 °C; and hydroxypropylcellulose (HPC), a mucoadhesive polymer. The three polymers were able to act synergistically, increasing the permanence of the vehicle on the mucosa and forming a protective gel layer. A DoE approach, "simplex centroid mixture design," was used to identify the optimal quantitative composition of the vehicle. The response variables considered were: vehicle viscosity at room temperature; increase in vehicle viscosity on increasing temperature (from room to physiological value) and upon dilution with simulated colonic fluid (SCF); and viscoelastic behavior, thixotropic area, and mucoadhesion properties of the gel formed at 37 °C upon dilution in SCF. The optimized vehicle was loaded with maqui berry extract (MBE), known for its antioxidant and anti-inflammatory properties. MBE loading (0.5% w/w) into the vehicle improved rheological and mucoadhesive properties of the formulation. Both MBE and the optimized vehicle were not cytotoxic towards human fibroblasts and Caco-2 cells. Moreover, the optimized vehicle did not affect MBE antioxidant properties.

Nanoparticles for the regulation of intestinal inflammation: opportunities and challenges

Prevalence of chronic inflammation of the gastrointestinal tract is increasing, emerging as a public health challenge. Conventional drug delivery systems targeting the colon have improved the treatment of inflammatory bowel disease. However, therapy frequently results in inconsistent efficacy and toxicity problems. Novel approaches based on nanoparticles offer several advantages over conventional dosage forms due to their ability to selectively target inflamed tissues. Several formulation efforts have been made in order to obtain increasingly selective nanosized systems, some with promising results in animal models of colitis. Despite all advances, no nanomedicines are yet approved for clinical use in inflammatory bowel disease. This review discusses the most recent efforts made toward the development of nanoparticles for regulating chronic intestinal inflammation.

Acetyl-11-keto-β-boswellic acid attenuates titanium particle-induced osteogenic inhibition via activation of the GSK-3β/β-catenin signaling pathway

Rationale: Peri-prosthetic osteolysis (PPO) is mainly induced by wear particles and represents the leading cause of implant failure and revision surgery. Previous studies have identified mitigation of wear particle-induced inflammation and bone resorption as the main approaches to treat PPO. Recently, wear particle-induced reduction of bone formation around the prosthesis was identified as a major factor in the development of PPO. Acetyl-11-keto-β-boswellic acid (AKBA), a derivative of frankincense, has been shown to play a potential role in bone metabolism. However, whether AKBA enhances bone formation in wear particle-induced osteolysis remains unknown. In this study, we examined whether AKBA attenuates titanium particle-induced osteogenic reduction.

Methods: Titanium particles were used to induce osteolysis in murine calvaria, and micro-CT and histological analyses were used to evaluate the results. Mouse osteoblast cells, MC3T3-E1 were co-cultured with titanium particles to determine their effect on osteoblast formation in vitro.

Results: We demonstrated that AKBA treatment significantly inhibited titanium particle-induced osteogenic inhibition by enhancing osteogenesis both in vivo and in vitro. AKBA treatment also enhanced the phosphorylation of GSK-3β, decreased the degradation of β-catenin, and increased the translocation of β-catenin from the cytoplasm to the nucleus. Taken together, these results showed that AKBA treatment attenuated titanium-induced osteogenic inhibition by activating the GSK-3β/β-catenin signaling pathway.

Conclusion: These findings suggest that AKBA is a promising new target in the prevention and treatment of PPO.

Sustained effectiveness, safety and therapeutic drug monitoring of tioguanine in a cohort of 274 IBD patients intolerant for conventional therapies

BACKGROUND

Tioguanine (or thioguanine) is an alternative drug for IBD patients who fail prior conventional immunomodulating therapy.

AIM

To report effectiveness, safety and therapeutic drug monitoring in a cohort of patients with prolonged tioguanine maintenance therapy.

METHODS

In this nationwide, multicentre study, medical records of tioguanine- using IBD patients were retrospectively reviewed. Response to therapy was defined as clinical effectiveness without (re)initiation of corticosteroids, concurrent biological therapy or surgical intervention. All adverse events that occurred during the follow-up were listed and graded according to the common terminology criteria (CTC).

RESULTS

Two hundred and seventy-four patients (female 63%, Crohn's disease in 68%) were included with median treatment duration of 51 months, 1567 patient-years of follow-up and median 20 mg/d tioguanine dosage. Tioguanine was tolerated in 79%, clinical effectiveness at 6 months was documented in 66% and sustained clinical effectiveness during 12 months in 51% of patients. Forty-one per cent of patients developed adverse events: 5% were graded as severe. Adverse events comprised infection requiring hospitalisation in three and skin cancer in eight patients (two melanomas). Asymptomatic nodular regenerative hyperplasia of the liver occurred in two out of 52 patients with liver biopsies (3.8%) and portal hypertension in three whereof one potentially associated with tioguanine (0.4%). Clinical effectiveness was correlated with 6-thioguanine nucleotide threshold concentrations >682 pmol/8×10⁸ RBC (P < 0.05).

CONCLUSIONS

Long-term tioguanine therapy for at least 12 months was effective in 51% and well tolerated as a maintenance treatment for IBD in about 70% of patients. Adverse events were common, but mainly mild or moderate. 6-Thioguanine nucleotide threshold concentration ≥ 700 pmol/8×10⁸ RBC is proposed as target level with higher odds for clinical effectiveness.

Effect of Shogaol on the Expression of Intestinal Stem Cell Markers in Experimentally Induced Colitis in BALB/c Mice

Aim

This study is aimed at investigating the effect of Shogaol, a phenolic constituent of ginger, on dextran sodium sulfate- (DSS-) induced ulcerative colitis (UC) in mice in comparison with 6-thioguanine (6-TG), an immune-suppressant chemotherapeutic medicine used for treatment of ulcerative colitis.

Material & Methods

Thirty-six adult, male and female BALB/c mice were randomly divided into six groups: group 1 (control negative) not exposed to DSS and did not receive any treatment, group 2 (control positive) exposed to DSS but did not receive any treatment, group 3 exposed to DSS and treated by 0.1 mg/kg of 6-thioguanine, and groups 4, 5, and 6 exposed to DSS and treated by 10, 20, and 40 mg/kg b.w. Shogaol, respectively. At day 56, the mice were checked for their disease activity index (DAI) and they were sacrificed. The colons of the mice were examined for length measurement, histological index score, and the expression of CD133 and CD34 stem cell markers.

Results

Shogaol showed a better curative effect than did 6-TG in repairing the colonic mucosal damages in DSS-exposed mice as indicated by the levels of CD133 and CD34 expression in the colonic crypts and by the DAI score, colon length measurements, & histological index score which were significantly reduced in mice treated by Shogaol, particularly the 20 and 40 mg/kg BW doses.

Conclusion

The results of this study indicated that oral treatment with the ginger-derived substance Shogaol could be better than the conventional immunosuppressive chemotherapeutic remedy 6-TG in treatment of DSS-induced UC.

Delivery of tacrolimus with cationic lipid-assisted nanoparticles for ulcerative colitis therapy

Oral drug delivery with nanoparticles has demonstrated great potential for drugs with poor bioavailability. Efficient delivery is possible by overcoming both the mucus and epithelial barrier of the gastrointestinal tract (GIT). Cationic lipid-assisted nanoparticles (CLANs), which are composed of amphiphilic block copolymers and cationic lipids, have been well studied and have been proved beneficial for drug delivery. In this study, CLANs prepared by poly(ethylene glycol)-block-poly(lactic acid) (PEG-b-PLA) and 1,2-dioleoyl-3-trimethylammonium-propanechloride (DOTAP) or N,N-bis(2-hydroxyethyl)-N-methyl-N-(2-cholesteryloxycarbonyl aminoethyl)ammoniumbromide (BHEM-Chol) were used for oral delivery of tacrolimus (FK506) for ulcerative colitis treatment. The average size of these nanoparticles is around 110 nm and the zeta-potential is 35 mV. These nanoparticles maintained their size in buffer solutions of pH 1.2 and 6.8, and slowly release the encapsulated drug. CLANs can be accumulated in the colon and transported through the epithelium in the colitis model by dextran sulfate sodium salt (DSS), leading to attenuation of DSS-induced colitis.

Mercaptopurine and inflammatory bowel disease: the other thiopurine

BACKGROUND

Data about use and effectiveness of mercaptopurine in inflammatory bowel disease are relatively limited.

AIMS

To assess the possible therapeutic indications, efficacy and safety of mercaptopurine as an alternative to azathioprine in inflammatory bowel disease.

METHODS

Retrospective observational study in patients treated with mercaptopurine in a total cohort of 1,574 patients with inflammatory bowel disease.

RESULTS

One hundred and fifty-two patients received mercaptopurine, 15.7% of these patients as an initial thiopurine, 5.3% after azathioprine failure, and 79% after azathioprine intolerance. In 52.6% of patients (n = 80), adverse effects of mercaptopurine occurred, resulting in withdrawal in 49 of them. Mercaptopurine was effective in 39% of cases (95% CI 31-48%). In the remaining patients, failure was due mainly to withdrawal due to side effects (55.1%) and therapeutic step-up (33.7%). The average total time of mercaptopurine exposure was 36 months (IQR: 2-60). Myelotoxicity with mercaptopurine was more common in patients with intermediate TPMT activity than in those with normal activity (p = 0.046).

CONCLUSIONS

In our setting, mercaptopurine is primarily used as a rescue therapy in patients with azathioprine adverse effects. This could explain its modest efficacy and the high rate of adverse effects. However, this drug is still an alternative in this group of patients, before a therapeutic step-up to biologics is considered.

Investigation of mitigating effect of colon-specific prodrugs of boswellic acid on 2,4,6-trinitrobenzene sulfonic acid-induced colitis in Wistar rats: Design, kinetics and biological evaluation

AIM

To develop a colon-targeting bioreversible delivery system for β-boswellic acid (BBA) and explore utility of its prodrugs in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.

METHODS

Synthesis of 4 co-drugs of BBA with essential amino acids was achieved by CDI coupling, followed by their spectral characterization. In vitro kinetics were studied by HPLC in aqueous buffers, homogenates of gastrointestinal tract and fecal matter. In vivo kinetic studies were performed in Wistar rat plasma, urine and feces. The prodrugs were screened in TNBS-induced colitis modeled Wistar rats. Statistical significance was assumed at P < 0.05, P < 0.01, P < 0.001 when compared with disease controls using one-way and two-way ANOVAs.

RESULTS

Prodrugs were stable in 0.05 mol/L HCl buffer (pH 1.2) and stomach homogenates. Negligible hydrolysis was observed in phosphate buffer and intestinal homogenates. Substantial release (55%-72% and 68%-86%) of BBA was achieved in rat fecal matter and homogenates of colon. In vivo studies of BBA with L-tryptophan (BT) authenticated colon-specific release of BBA. But, surprisingly substantial concentration of BBA was seen to reach the systemic circulation due to probable absorption through colonic mucosa. Site-specifically enhanced bioavailability of BBA could be achieved in colon, which resulted in demonstration of significant mitigating effect on TNBS-induced colitis in rats without inducing any adverse effects on stomach, liver and pancreas. Prodrug of BT was found to be 1.7% (P < 0.001) superior than sulfasalazine in reducing the inflammation to colon among all prodrugs tested.

CONCLUSION

The outcome of this study strongly suggests that these prodrugs might have dual applicability to inflammatory bowel disease and chronotherapy of rheumatoid arthritis.

Microparticles as controlled drug delivery carrier for the treatment of ulcerative colitis: A brief review

Ulcerative colitis is the chronic relapsing multifactorial gastrointestinal inflammatory bowel disease, which is characterized by bloody or mucus diarrhea, tenesmus, bowel dystension, anemia. The annual incidence of ulcerative colitis in Asia, North America and Europe was found to be 6.3, 19.2 and 24.3 per 100,000 person-years. The major challenge in the treatment of ulcerative colitis is appropriate local targeting and drug related side-effects. To overcome these challenges, microparticulate systems seem to be a promising approach for controlled and sustained drug release after oral administration. The main goal of this article is to explore the role of microparticles in ulcerative colitis for the appropriate targeting of drugs to colon. There are different approaches which have been studied over the last decade, including prodrugs, polymeric approach, time released system, pH sensitive system, which show the site specific drug delivery to colon. Among these approaches, microparticulate drug delivery system has been gaining an immense importance for local targeting of drug to colon at a controlled and sustained rate. Combined approaches such as pH dependent and time dependent system provide the maximum release of drug into colon via oral route. This article embraces briefly about pathophysiology, challenges and polymeric approaches mainly multiparticulate systems for site specific drug delivery to colon in sustained and controlled manner so that drug related side-effects by reducing dosage frequency can be minimized.

Protective effects of ψ taraxasterol 3-O-myristate and arnidiol 3-O-myristate isolated from Calendula officinalis on epithelial intestinal barrier

The triterpene esters ᴪ taraxasterol-3-O-myristate (1) and arnidiol-3-O-myristate (2) were tested for their ability to protect epithelial intestinal barrier in an in vitro model. Their effects on ROS production and on trans-epithelial resistance were investigated on CaCo-2 cell monolayers both in basal and stress-induced conditions. Both compounds were able to modulate the stress damage induced by H2O2 and INFγ+TNFα, showing a potential use as model compounds for the study of new therapeutic agents for intestinal inflammations.

International Union of Basic and Clinical Pharmacology. XCVI. Pattern recognition receptors in health and disease

Since the discovery of Toll, in the fruit fly Drosophila melanogaster, as the first described pattern recognition receptor (PRR) in 1996, many families of these receptors have been discovered and characterized. PRRs play critically important roles in pathogen recognition to initiate innate immune responses that ultimately link to the generation of adaptive immunity. Activation of PRRs leads to the induction of immune and inflammatory genes, including proinflammatory cytokines and chemokines. It is increasingly clear that many PRRs are linked to a range of inflammatory, infectious, immune, and chronic degenerative diseases. Several drugs to modulate PRR activity are already in clinical trials and many more are likely to appear in the near future. Here, we review the different families of mammalian PRRs, the ligands they recognize, the mechanisms of activation, their role in disease, and the potential of targeting these proteins to develop the anti-inflammatory therapeutics of the future.

Histological healing after infliximab induction therapy in children with ulcerative colitis

AIM: To verify the impact of induction therapy with infliximab (IFX) on mucosal healing in children with ulcerative colitis (UC).

METHODS: The study included all UC pediatric patients treated with IFX at our center over the last 10 years. The data were collected from patients’ medical charts and analyzed retrospectively. A total of 16 patients with UC underwent colonoscopy with sample collection before and after three IFX injections. Pediatric Ulcerative Colitis Activity Index (PUCAI) was used to assess the clinical condition; endoscopic features were classified according to the Baron scale; and histological changes were evaluated according to the protocol of The British Society of Gastroenterology and Geboes Index. Clinical response was defined as a ≥ 20-point reduction in PUCAI index, and clinical remission as PUCAI index < 10 points. Endoscopic mucosal remission was defined as completely normal (score 0) on the Baron scale. Histological remission was defined as grade 0 in the Geboes Index. To assess correlation between variables, Spearman’s rank correlation coefficient was used.

RESULTS: Clinical remission (PUCAI < 10) at week 8 was achieved in 68.75% of investigated subjects. Endoscopic mucosal remission at week 8 (Baron 0) was observed in 12.5% of patients. Histological remission (Geboes 0) after induction therapy with IFX was noticed in 18.75% cases. A general histological improvement, expressed by normal surface and crypt architecture, number of crypts, and lamina propria cellularity, was observed in six (37.5%) patients; there was no improvement in nine (56.25%) individuals, and worsening was observed in one (3.75%) case. Changes were not related to UC location. A reduction of inflammatory process was observed in 10 (62.5%) patients; there were no changes in four (25%) individuals, and the inflammation became more severe in two (12.5 %) cases. Simultaneous clinical, endoscopic and histological improvement of parameters assessing disease activity at week 8 was noticed in six (37.5%) patients. 55.5% of investigated patients with normal mucosa seen on endoscopy showed no inflammation on histology. A Baron score of 2 and 3 showed a good correlation with histology results (78.2% of patients with a Geboes Index ≥ 3).

CONCLUSION: IFX has a positive histological effect in more than one-third of UC patients. IFX reduces intestinal inflammation and improves clinical condition.

The protective effect of piperine on dextran sulfate sodium induced inflammatory bowel disease and its relation with pregnane X receptor activation

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory bowel disease (IBD) is associated with chronic inflammation of the intestinal tract. Piperine (1-peperoylpiperidine), the primary lipophilic component in black pepper (Piper nigrum) and long pepper (Piper longum), has been reported to be effective for anti-inflammatory. Rencently, several ethnopharmacological purity compounds, such as baicalin and artemisinin, are reported to have potentially therapeutic role in treating IBD. In the present study, the effects of piperine on pregnane X receptor (PXR)-mediated CYP3A expression and its therapeutic role in IBD were investigated.

MATERIALS AND METHODS

LS174T cells and C57BL/6J mice were treated by the piperine. Gene expressions were analyzed by real-time PCR, Western blot analysis, transient transfections assay and histological analysis.

RESULTS

Data indicated that treatment of LS174T cells with piperine markedly increased both CYP3A4 and PXR mRNA and protein. Transient transfection experiments indicated that transcriptional activation of the CYP3A4 gene via piperine was PXR-dependent. Data show that pre-administration of piperine decreased clinical hallmarks of colitis in DSS-treated PXR mice as measured by body weight loss and assessment of diarrhea, rectal bleeding, colon length, and histology. Inflammatory mediators (CCR2, ICAM-1, IL-1β, IL-6, IL-10, iNOS, MCP-1, and TNFα) after DSS treatment were significantly decreased in mice pretreated with piperine but corresponding conditions did not occur in mice with down-regulation of PXR by small interfering RNA (siRNA).

CONCLUSION

Piperine is a potential agonist of PXR and an inducer of PXR, which may induce CYP3A4 gene expression at the mRNA and protein levels. These results establish that piperine may contribute to prevention or reduction of colonic inflammation.

Classical and recent advances in the treatment of inflammatory bowel diseases

Crohn's disease (CD) and ulcerative colitis (UC) are intestinal disorders that comprise the inflammatory bowel diseases (IBD). These disorders have a significant effect on the quality of life of affected patients and the increasing number of IBD cases worldwide is a growing concern. Because of the overall burden of IBD and its multifactorial etiology, efforts have been made to improve the medical management of these inflammatory conditions. The classical therapeutic strategies aim to control the exacerbated host immune response with aminosalicylates, antibiotics, corticosteroids, thiopurines, methotrexate and anti-tumor necrosis factor (TNF) biological agents. Although successful in the treatment of several CD or UC conditions, these drugs have limited effectiveness, and variable responses may culminate in unpredictable outcomes. The ideal therapy should reduce inflammation without inducing immunosuppression, and remains a challenge to health care personnel. Recently, a number of additional approaches to IBD therapy, such as new target molecules for biological agents and cellular therapy, have shown promising results. A deeper understanding of IBD pathogenesis and the availability of novel therapies are needed to improve therapeutic success. This review describes the overall key features of therapies currently employed in clinical practice as well as novel and future alternative IBD treatment methods.

Prom1 function in development, intestinal inflammation, and intestinal tumorigenesis

Prom1/CD133 has been identified in colorectal, hepatocellular, and pancreatic cancer as a cancer stem cell marker and has been used as such to predict colon cancer recurrence in humans. Its potential molecular function as well as its role as a marker of intestinal regeneration is still not fully known. We evaluated the role of Prom1 in intestinal regeneration in inflammatory bowel disease (IBD), determined the function of Prom1, and characterized the effect of a lack of Prom1 on intestinal tumor formation in animal models. Our results suggest that Apc mutations lead to an increase in Prom1 expressing cells in the intestinal crypt stem cell compartment and in early intestinal adenomas. Also, Prom1 knockout mice are more susceptible to intestinal tumor formation. We conclude that Prom1 likely plays a role in regulating intestinal homeostasis and that these results clearly illustrate the role of Prom1 in intestinal regeneration. We further conclude that Prom1 may provide a novel therapeutic target for patients with gastrointestinal conditions such as IBD, short bowel syndrome, and colorectal cancer.

Live Combined Bacillus subtilis and Enterococcus faecium Ameliorate Murine Experimental Colitis by Immunosuppression

Live combined Bacillus subtilis and Enterococcus faecium ameliorate murine experimental colitis by immunosuppression manifested by downregulation of TLRs, macrophages, Th1, and Th2 but upregulation of Tregs.

Disruption of Pten speeds onset and increases severity of spontaneous colitis in Il10(-/-) mice

BACKGROUND & AIMS

Early-onset ulcerative colitis, which is considered severe colonic inflammation that develops in infants and young children, can be caused by alterations in interleukin (IL)-10 signaling, although other factors are involved in its pathogenesis. We investigated whether loss of phosphatase and tensin homologue (PTEN), which regulates many important cell functions such as cell proliferation, cell survival, and Toll-like receptor (TLR) signaling pathways, contributes to the development of colitis in Il10(-/-) mice.

METHODS

We generated Il10(-/-) mice (in C57BL/6 and C3H/HeJBir background strains) with disruption of Pten in the intestinal epithelium (Ints(ΔPten/ΔPten);Il10(-/-) mice) and Ints(ΔCont);Il10(-/-) (control) mice. Colon tissues were collected and histological, transmission electron microscopy, and gene expression analysis were performed. Fecal microbiota samples were analyzed by sequencing of 16S ribosomal RNA genes. We disrupted Tlr4 in Ints(ΔPten/ΔPten);Il10(-/-) mice. Lipopolysaccharide signaling via TLR4 was blocked by treating mice with polymyxin B.

RESULTS

Il10(-/-) mice developed colitis when they were 6 to 7 months old, whereas Ints(ΔPten/ΔPten);Il10(-/-) mice developed severe colitis and colon tumors by the time they were 36 days old. Within 3 months of birth, 80% of Ints(ΔPten/ΔPten);Il10(-/-) mice developed severe colitis and colonic malignancy, whereas none of the Ints(ΔCont);Il10(-/-) mice had these phenotypes. Ints(ΔPten/ΔPten);Il10(-/-) mice had alterations in fecal microbiota compared with controls, such as increased proportions of Bacteroides species, which are gram negative. Disruption of Tlr4 or treating Ints(ΔPten/ΔPten);Il10(-/-) mice with polymyxin B delayed the development of colitis and reduced disease severity.

CONCLUSIONS

Disruption of Pten in the intestinal epithelium of Il10(-/-) mice speeds the onset and increases the severity of colitis. Fecal microbiota from Ints(ΔPten/ΔPten);Il10(-/-) mice have increased proportions of Bacteroides species. Development of colitis is delayed and reduced by blocking TLR4 signaling. Ints(ΔPten/ΔPten);Il10(-/-) mice may be studied as a model for early-onset ulcerative colitis and used to identify new therapeutic targets.

Are we using and monitoring thiopurines and biologics optimally?

The use of biologics and thiopurines in patients with inflammatory bowel disease has increased rapidly over the last 2 decades with both classes of drugs being used more frequently and earlier in the disease course. This vogue has come about through a realisation that for some patients Crohn's disease and ulcerative colitis are progressive diseases and that use of these therapies can sometimes prevent that progression. However, knowledge about the optimal way in which to use these drugs continues to evolve. In this paper, the evidence regarding optimal timing and dosing of thiopurines and biologics will be reviewed as will the role of thiopurine methyltransferase testing along with therapeutic drug monitoring of both thiopurines and biologics. In addition, possible future applications of biologic drug level and anti-drug antibody testing will be considered.

Can we get more from our current treatments?

Crohn's disease is a chronic incurable condition that normally requires lifelong treatment. Whilst the anti-TNF agents have revolutionised the management of Crohn's disease over the last fifteen years, they are not a panacea. In particular, in part due to their immunogenic nature, loss of response limits their long term effectiveness in many patients. The only other long term disease-modifying options are the immunomodulators, methotrexate, azathioprine and mercaptopurine. Therefore, given the limited number of drugs available to treat Crohn's disease, it is important that efforts are made to ensure that drugs are used in the best way possible as once a drug is deemed ineffective, it is rarely used again. For the growing number of patients who have active disease despite having been exposed to all standard therapies, failure to optimise drug therapy may lead to missed opportunities in the management of their disease. In this review, optimisation of drugs commonly used in the management of Crohn's disease will be discussed.

Drug delivery strategies in the therapy of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a frequently occurring disease in young people, which is characterized by a chronic inflammation of the gastrointestinal tract. The therapy of IBD is dominated by the administration of anti-inflammatory and immunosuppressive drugs, which suppress the intestinal inflammatory burden and improve the disease-related symptoms. Established treatment strategies are characterized by a limited therapeutical efficacy and the occurrence of adverse drug reactions. Thus, the development of novel disease-targeted drug delivery strategies is intended for a more effective therapy and demonstrates the potential to address unmet medical needs. This review gives an overview about the established as well as future-oriented drug targeting strategies, including intestine targeting by conventional drug delivery systems (DDS), disease targeted drug delivery by synthetic DDS and disease targeted drug delivery by biological DDS. Furthermore, this review analyses the targeting mechanisms of the respective DDS and discusses the possible field of utilization in IBD.

A trial of mercaptopurine is a safe strategy in patients with inflammatory bowel disease intolerant to azathioprine: an observational study, systematic review and meta-analysis

BACKGROUND

Thiopurines maintain remission and modify disease course in inflammatory bowel disease. Use is limited by intolerance and subsequent drug withdrawal in approximately 17% of patients treated with azathioprine. Previous case series have addressed the success rates of re-treatment with mercaptopurine in these individuals.

AIMS

To determine the rate of tolerance when trialling mercaptopurine in azathioprine-intolerant patients and the factors predictive of success, and to perform a systematic review and meta-analysis of these data with other published data sets.

METHODS

A retrospective observational study of 149 patients with IBD (82 with Crohn's disease and 67 with ulcerative colitis) previously intolerant of azathioprine subsequently treated with mercaptopurine was performed. A meta-analysis was undertaken of all published studies of mercaptopurine use in azathioprine-intolerant patients (455 patients in 11 included studies).

RESULTS

Mercaptopurine was tolerated by 58% of azathioprine-intolerant patients in the Edinburgh cohort. In the meta-analysis, 68% tolerated mercaptopurine. A higher proportion of those in the meta-analysis with GI toxicity (62%) or hepatotoxicity (81%) were able to tolerate mercaptopurine than those with flu-like illness (36%). Among those patients who ceased mercaptopurine for further adverse effects, 59% experienced the same adverse effect as they had with azathioprine.

CONCLUSIONS

This meta-analysis shows that switching to mercaptopurine is a safe therapeutic strategy for over two-thirds of azathioprine-intolerant patients and may help optimise immunomodulatory therapy in inflammatory bowel disease. A trial of mercaptopurine should be attempted in IBD patients (except those with acute pancreatitis or bone marrow aplasia) before considering thiopurine intolerance.

Activation of protein tyrosine phosphatase non-receptor type 2 by spermidine exerts anti-inflammatory effects in human THP-1 monocytes and in a mouse model of acute colitis

Background

Spermidine is a dietary polyamine that is able to activate protein tyrosine phosphatase non-receptor type 2 (PTPN2). As PTPN2 is known to be a negative regulator of interferon-gamma (IFN-γ)-induced responses, and IFN-γ stimulation of immune cells is a critical process in the immunopathology of inflammatory bowel disease (IBD), we wished to explore the potential of spermidine for reducing pro-inflammatory effects in vitro and in vivo.

Methods

Human THP-1 monocytes were treated with IFN-γ and/or spermidine. Protein expression and phosphorylation were analyzed by Western blot, cytokine expression by quantitative-PCR, and cytokine secretion by ELISA. Colitis was induced in mice by dextran sodium sulfate (DSS) administration. Disease severity was assessed by recording body weight, colonoscopy and histology.

Results

Spermidine increased expression and activity of PTPN2 in THP-1 monocytes and reduced IFN-γ-induced phosphorylation of signal transducer and activator of transcription (STAT) 1 and 3, as well as p38 mitogen-activated protein kinase (MAPK) in a PTPN2 dependent manner. Subsequently, IFN-γ-induced expression/secretion of intracellular cell adhesion molecule (ICAM)-1 mRNA, monocyte chemoattractant protein (MCP)-1, and interleukin (IL)-6 was reduced in spermidine-treated cells. The latter effects were absent in PTPN2-knockdown cells. In mice with DSS-induced colitis, spermidine treatment resulted in ameliorated weight loss and decreased mucosal damage indicating reduced disease severity.

Conclusions

Activation of PTPN2 by spermidine ameliorates IFN-γ-induced inflammatory responses in THP-1 cells. Furthermore, spermidine treatment significantly reduces disease severity in mice with DSS-induced colitis; hence, spermidine supplementation and subsequent PTPN2 activation may be helpful in the treatment of chronic intestinal inflammation such as IBD.