Modulation of Gut Barrier Functions in Ulcerative Colitis by Hyaluronic Acid System

Hyaluronic Acid Receptor-Mediated Nanomedicines and Targeted Therapy

Hyaluronic acid (HA) is a naturally occurring polysaccharide found in the extracellular matrix with broad applications in disease treatment. HA possesses good biocompatibility, biodegradability, and the ability to interact with various cell surface receptors. Its wide range of molecular weights and modifiable chemical groups make it an effective drug carrier for drug delivery. Additionally, the overexpression of specific receptors for HA on cell surfaces in many disease states enhances the accumulation of drugs at pathological sites through receptor binding. In this review, the modification of HA with drugs, major receptor proteins, and the latest advances in receptor-targeted nano drug delivery systems (DDS) for the treatment of tumors and inflammatory diseases are summarized. Furthermore, the functions of HA with varying molecular weights of HA in vivo and the selection of drug delivery methods for different diseases are discussed.

Biomimetic Supramolecular Assembly with IGF-1C Delivery Ameliorates Inflammatory Bowel Disease (IBD) by Restoring Intestinal Barrier Integrity

The management of dysfunctional intestinal epithelium by promoting mucosal healing and modulating the gut microbiota represents a novel therapeutic strategy for inflammatory bowel disease (IBD). As a convenient and well-tolerated method of drug delivery, intrarectal administration may represent a viable alternative to oral administration for the treatment of IBD. Here, a biomimetic supramolecular assembly of hyaluronic acid (HA) and β-cyclodextrin (HA-β-CD) for the delivery of the C domain peptide of insulin-like growth factor-1 (IGF-1C), which gradually releases IGF-1C, is developed. It is identified that the supramolecular assembly of HA-β-CD enhances the stability and prolongs the release of IGF-1C. Furthermore, this biomimetic supramolecular assembly potently inhibits the inflammatory response, thereby restoring intestinal barrier integrity. Following HA-β-CD-IGF-1C administration, 16S rDNA sequencing reveals a significant increase in the abundance of the probiotic Akkermansia, suggesting enhanced intestinal microbiome homeostasis. In conclusion, the findings demonstrate the promise of the HA-based mimicking peptide delivery platform as a therapeutic approach for IBD. This biomimetic supramolecular assembly effectively ameliorates intestinal barrier function and intestinal microbiome homeostasis, suggesting its potential for treating IBD.

Restore Intestinal Barrier Integrity: An Approach for Inflammatory Bowel Disease Therapy

The intestinal barrier maintained by various types of columnar epithelial cells, plays a crucial role in regulating the interactions between the intestinal contents (such as the intestinal microbiota), the immune system, and other components. Dysfunction of the intestinal mucosa is a significant pathophysiological mechanism and clinical manifestation of inflammatory bowel disease (IBD). However, current therapies for IBD primarily focus on suppressing inflammation, and no disease-modifying treatments specifically target the epithelial barrier. Given the side effects associated with chronic immunotherapy, effective alternative therapies that promote mucosal healing are highly attractive. In this review, we examined the function of intestinal epithelial barrier function and the mechanisms of behind its disruption in IBD. We illustrated the complex process of intestinal mucosal healing and proposed therapeutic approaches to promote mucosal healing strategies in IBD. These included the application of stem cell transplantation and organ-like tissue engineering approaches to generate new intestinal tissue. Finally, we discussed potential strategies to restore the function of the intestinal barrier as a treatment for IBD.

CircSOD2: Disruption of intestinal mucosal barrier function in ulcerative colitis by regulating the miR-378g/Snail1 axis

BACKGROUND AND AIM

Circular RNA (circRNA) has been found to mediate ulcerative colitis (UC) progression by regulating intestinal mucosal barrier function. However, the role of circSOD2 in UC process and its underlying molecular mechanism still need to be further elucidated.

METHODS

Lipopolysaccharide (LPS)-induced Caco2 cells were used to mimic UC cell models. CircSOD2, miR-378g, and Snail1 levels were determined by quantitative real-time PCR. Cell viability was detected using MTT assay, and inflammatory cytokine levels were measured using ELISA. The intestinal mucosal barrier function was evaluated by testing transepithelial electrical resistance and fluorescein isothiocyanate (FITC)-dextran permeability. Snail1 and tight junction-related markers (Zo-1 and Claudin2) protein levels were examined using western blot. The interaction between miR-378g and circSOD2 or Snail1 was confirmed by dual-luciferase reporter assay. Dextran sulfate sodium (DSS) was used to induce UC rat models in vivo.

RESULTS

CircSOD2 was overexpressed in UC patients, and its knockdown significantly increased cell viability, transepithelial electrical resistance, and tight junction-related protein expression, while reduced inflammation cytokine levels and the permeability of FITC-dextran in LPS-induced Caco2 cells. In terms of mechanism, circSOD2 sponged miR-378g to positively regulate Snail1 expression. MiR-378g inhibitor reversed the effect of circSOD2 knockdown on intestinal mucosal barrier injury and Snail1 expression in LPS-induced Caco2 cells. In DSS-induced UC rat models, circSOD2 knockdown also could repair the intestinal mucosal barrier injury through regulating miR-378g/Snail1 axis.

CONCLUSION

CircSOD2 could destroy intestinal mucosal barrier function in LPS-induced Caco2 cells and DSS-induced UC rats by miR-378g/Snail1 axis.

High-Molecular-Weight Hyaluronic Acid Can Be Used as a Food Additive to Improve the Symptoms of Persistent Inflammation, Immunosuppression and Catabolism Syndrome (PICS)

Hyaluronic acid (HA) is a new functional food additive which has the potential to ameliorate persistent inflammation, immunosuppression and catabolism syndrome (PICS), but the biological effects of HA with various molecular weights differ dramatically. To systematically investigate the efficacy of HA in altering PICS symptoms, medium-molecular-weight (MMW) HA was specifically selected to test its intervention effect on a PICS mouse model induced by CLP through oral administration, with high-molecular-weight (HMW) and low-molecular-weight (LMW) HA also participating in the experimental validation process. The results of pathological observations and gut flora showed that MMW HA rapidly alleviated lung lesions and intestinal structural changes in PICS mice in the short term. However, although long-term MMW HA administration significantly reduced the proportions of harmful bacteria in gut flora, inflammatory responses in the intestines and lungs of PICS mice were significantly higher in the MMW HA group than in the HMW HA and LMW HA groups. The use of HMW HA not only rapidly reduced the mortality rate of PICS mice but also improved their grip strength and the recovery of spleen and thymus indices. Furthermore, it consistently promoted the recovery of lung and intestinal tissues in PICS mice, and it also assisted in the sustained restoration of their gut microbiota. These effects were superior to those of LMW HA and MMW HA. The experimental results indicate that HMW weight HA has the greatest potential to be an adjunct in alleviating PICS as a food additive, while the safety of other HAs requires further attention.

Bioinspired and biomimetic strategies for inflammatory bowel disease therapy

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory bowel disease with high morbidity and an increased risk of cancer or death, resulting in a heavy societal medical burden. While current treatment modalities have been successful in achieving long-term remission and reducing the risk of complications, IBD remains incurable. Nanomedicine has the potential to address the high toxic side effects and low efficacy in IBD treatment. However, synthesized nanomedicines typically exhibit some degree of immune rejection, off-target effects, and a poor ability to cross biological barriers, limiting the development of clinical applications. The emergence of bionic materials and bionic technologies has reshaped the landscape in novel pharmaceutical fields. Biomimetic drug-delivery systems can effectively improve biocompatibility and reduce immunogenicity. Some bioinspired strategies can mimic specific components, targets or immune mechanisms in pathological processes to produce targeting effects for precise disease control. This article highlights recent research on bioinspired and biomimetic strategies for the treatment of IBD and discusses the challenges and future directions in the field to advance the treatment of IBD.

Challenges and opportunities in inflammatory bowel disease: from current therapeutic strategies to organoid-based models

BACKGROUND

Inflammatory bowel disease (IBD) is an increasingly prevalent global health concern that has garnered substantial attention. However, the underlying mechanisms are still unclear and the current treatments have significant limitations. Intestinal organoids provide an in vitro model to explore the pathogenesis, test the therapeutic effects, and develop regenerative treatments as well as offer the potential to transform drug discovery of IBD.

METHODS

To advance our understanding of the whole story of IBD spanning from the pathogenesis to the current therapeutic strategies and latest advancements, a comprehensive search of major databases including PubMed, Scopus, and Web of Science was conducted to retrieve original articles and reviews related to IBD, organoids, pathogenesis and therapy.

RESULTS

This review deciphers the etiopathogenesis and the current therapeutic approaches in the treatment of IBD. Notably, critical aspects of intestinal organoids in IBD, such as their potential applications, viability, cell renewal ability, and barrier functionality are highlighted. We also discuss the advances, limitations, and prospects of intestinal organoids for precision medicine.

CONCLUSION

The latest strides made in research about intestinal organoids help elucidate intricate aspects of IBD pathogenesis, and pave the prospective avenues for novel therapeutic interventions.

Growth Factors-Loaded Temperature-Sensitive Hydrogel as Biomimetic Mucus Attenuated Murine Ulcerative Colitis via Repairing the Mucosal Barriers

The pathogenesis of ulcerative colitis (UC) is associated with the shedding of the gut mucus. Herein, inspired by the biological functions of mucus, growth factors-loaded in situ hydrogel (PHE-EK) was designed for UC treatment by integrating dihydrocaffeic acid-modified poloxamer as a thermosensitive material with hyaluronic acid (colitis-specific adhesive), epigallocatechin-3-gallate (antibacterial agent), and bioactive factors (KPV tripeptide and epidermal growth factor). PHE-EK presented good thermosensitive properties, as a flowable liquid at room temperature and gelled within 10 s when exposed to body temperature. PHE-EK hydrogel presented good mechanical strength with a strain of 77.8%. Moreover, PHE-EK hydrogel displayed antibacterial activity against Escherichia coli. Importantly, in vitro and in vivo adhesive tests showed that the PHE-EK hydrogel could specifically adhere to the inflamed colon via electrostatic interaction. When PHE-EK as a biomimetic mucus was rectally administrated to colitis rats, it effectively hindered the body weight loss, reduced the disease activity index and improved the colonic shorting. Moreover, the expression of pro-inflammatory cytokines (e.g., IL-1β, IL-6, and TNF-α) at the laminae propria or epitheliums of the colon for colitis rats was substantially inhibited by PHE-EK. Besides, the colonic epitheliums were well rearranged, and the tight junction proteins (Zonula-1 and Claudin-5) between them were greatly upregulated after PHE-EK treatment. Collectively, PHE-EK might be a promising therapy for UC.

Hyaluronic Acid-Conjugated Thermoresponsive Polymer-Based Bioformulation Enhanced Wound Healing and Gut Barrier Repair of a TNBS-Induced Colitis Injury Ex Vivo Model in a Dynamic Perfusion Device

Impairment of intestinal epithelium is a typical feature of inflammatory bowel disease (IBD) that causes leakage of bacteria and antigens from the intestinal lumen and thus results in persistent immune activation. Hence, healing and regeneration of the damaged gut mucosa is a promising therapeutic approach to achieve deep remission in IBD. Currently, available systemic therapies have moderate effects and are often associated with numerous side effects and malignancies. In this study, we aimed to develop a topical therapy by chemically conjugating a temperature-responsive polymer, i.e., poly(N-isopropylacrylamide), along with hyaluronic acid to obtain a sprayable therapeutic formulation that upon colon instillation adheres to the damaged gut mucosa due to its temperature-induced phase transition and mucoadhesive properties. An ex vivo adhesion experiment demonstrates that this therapeutic formulation forms a thin physical coating on the mucosal lining at a physiological temperature within 5 min. Physicochemical characterization of (P(NIPAM-co-NTBAM)-HA) established this formulation to be biocompatible, hemo-compatible, and non-immunogenic. Prednisolone was encapsulated within the polymer formulation to achieve maximum therapeutic efficacy in the case of IBD-like conditions as assessed in a custom-fabricated perfusion-based ex vivo model system. Histological analysis suggests that the prednisolone-encapsulated polymer formulation nearly restored the mucosal architecture after 2,4,6-trinitrobenzenesulfonic acid-induced damage. Furthermore, a significant (p ≤ 0.001) increase in mRNA levels of Muc-2 and ZO-1 in treated groups further confirmed the mucosal epithelial barrier restoration.

Horizontal and vertical microchamber platforms for evaluation of the paracellular permeability of an epithelial cell monolayer

Epithelial cells serve as a barrier by tightly adhering to each other and contribute to the homeostasis of living organisms by controlling substance permeation. Therefore, evaluation of the barrier function is important in pharmaceutical development processes. However, the widely used Transwell-based assays require the development of the defect-free epithelial cell monolayer above several tens of mm2, often resulting in low reproducibility and requiring a long incubation time. In addition, the culture surface of cells is far from the bottom of the well plate, making it difficult to observe the cell morphology using an optical microscope. Herein, we propose simple polydimethylsiloxane microfluidic devices for evaluating the barrier function of an epithelial monolayer using a microchamber array. After the formation of the epithelial monolayer over microchambers, the permeation of the marker molecules introduced above resulted in increased fluorescence intensity in microchambers, which was monitored using confocal laser scanning microscopy. We show that using this technique, alteration of the paracellular permeability induced by sodium caprate (C10) and cytochalasin-D, permeation enhancing factors, can be elucidated. Furthermore, by tilting the microchamber device 90 degrees, the vertical cell section and microchambers were imaged in the same focal plane, allowing for live visualization of the passage of fluorescent substances across the cell monolayer. This technique is expected to be useful for investigating the relationship between paracellular permeability and cell morphology, which is unattainable through conventional methods.

The NF-κB signaling system in the immunopathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is an idiopathic, chronic condition characterized by episodes of inflammation in the gastrointestinal tract. The nuclear factor κB (NF-κB) system describes a family of dimeric transcription factors. Canonical NF-κB signaling is stimulated by and enhances inflammation, whereas noncanonical NF-κB signaling contributes to immune organogenesis. Dysregulation of NF-κB factors drives various inflammatory pathologies, including IBD. Signals from many immune sensors activate NF-κB subunits in the intestine, which maintain an equilibrium between local microbiota and host responses. Genetic association studies of patients with IBD and preclinical mouse models confirm the importance of the NF-κB system in host defense in the gut. Other studies have investigated the roles of these factors in intestinal barrier function and in inflammatory gut pathologies associated with IBD. NF-κB signaling modulates innate and adaptive immune responses and the production of immunoregulatory proteins, anti-inflammatory cytokines, antimicrobial peptides, and other tolerogenic factors in the intestine. Furthermore, genetic studies have revealed critical cell type-specific roles for NF-κB proteins in intestinal immune homeostasis, inflammation, and restitution that contribute to the etiopathology of IBD-associated manifestations. Here, we summarize our knowledge of the roles of these NF-κB pathways, which are activated in different intestinal cell types by specific ligands, and their cross-talk, in fueling aberrant intestinal inflammation. We argue that an in-depth understanding of aberrant immune signaling mechanisms may hold the key to identifying predictive or prognostic biomarkers and developing better therapeutics against inflammatory gut pathologies.

Gastroprotective Effects of Oral Glycosaminoglycans with Sodium Alginate in an Indomethacin-Induced Gastric Injury Model in Rats

The gastrointestinal (GI) mucosal barrier is often exposed to inflammatory and erosive insults, resulting in gastric lesions. Glycosaminoglycans (GAGs), such as hyaluronic acid (HA), chondroitin sulfate (CS), and N-acetylglucosamine (NAG) have shown potential beneficial effects as GI protectants. This study aimed to evaluate the gastroprotective effects of oral GAGs in rats with indomethacin-induced GI lesions. Forty-five Sprague-Dawley rats (8-9 weeks-old, 228 ± 7 g) were included in the study, divided into five study groups, and given, administered orally, either sucralfate (positive control group; PC), NAG (G group), sodium alginate plus HA and CS (AHC group), sodium alginate plus HA, CS, and NAG (AHCG group), or no treatment (negative control group; NC). Animals were administered 12.5 mg/kg indomethacin orally 15 min after receiving the assigned treatment. After 4 h, stomach samples were obtained and used to perform a macroscopic evaluation of gastric lesions and to allow histological assessment of the gastric wall (via H/E staining) and mucous (via PAS staining). The AHCG group showed significant gastroprotective improvements compared to the NC group, and a similar efficacy to the PC group. This combination of sodium alginate with GAGs might, therefore, become a safe and effective alternative to prescription drugs for gastric lesions, such as sucralfate, and have potential usefulness in companion animals.

Targeted delivery of budesonide in acetic acid induced colitis: impact on miR-21 and E-cadherin expression

Inflammatory bowel disease (IBD) is characterized by chronic inflammation along the gastrointestinal tract. For IBD effective treatment, developing an orally administered stable drug delivery system capable of targeting inflammation sites is a key challenge. Herein, we report pH responsive hyaluronic (HA) coated Eudragit S100 (ES) nanoparticles (NPs) for the targeted delivery of budesonide (BUD) (HA-BUD-ES-NPs). HA-BUD-ES-NPs showed good colloidal properties (274.8 ± 2.9 nm and - 24.6 ± 2.8 mV) with high entrapment efficiency (98.3 ± 3.41%) and pH-dependent release profile. The negative potential following incubation in simulated gastrointestinal fluids reflected the stability of HA coat. In vitro studies on Caco-2 cells showed HA-BUD-ES-NPs biocompatibility and enhanced cellular uptake and anti-inflammatory effects as shown by the significant reduction in IL-8 and TNF-α. The oral administration of HA-BUD-ES-NPs in an acetic acid induced colitis rat model significantly mitigated the symptoms of IBD, and improved BUD therapeutic efficacy compared to drug suspension. This was proved via the improvement in disease activity index and ulcer score in addition to refined histopathological findings. Also, the assessment of inflammatory markers, epithelial cadherin, and mi-R21 all reflected the higher efficiency of HA-BUD-ES-NPs compared to free drug and uncoated formulation. We thus suggest that HA-BUD-ES-NPs provide a promising drug delivery platform for the management and site specific treatment of IBD.

Rosa Roxburghii Tratt Fruit Extract Prevents Dss-Induced Ulcerative Colitis in Mice by Modulating the Gut Microbiota and the IL-17 Signaling Pathway

Ulcerative colitis (UC) is a non-specific inflammatory bowel illness characterized by intestinal mucosal barrier degradation, inflammation, oxidative damage, and gut microbiota imbalances. Rosa roxburghii Tratt Fruit extract (RRTE) was extracted from Rosa roxburghii Tratt fruit, exhibiting an excellent prevention effect against UC; RRTE could prevent the damage of DSS-induced human normal colonic epithelial (NCM 460) cells, especially in cell viability and morphology, and oxidative damage. Additionally, in UC mice, RRTE could limit the intestinal mucosal barrier by increasing the expression of intestinal tight junction proteins and mucin, reducing inflammation and oxidative damage in colon tissue. More importantly, RRTE can increase the abundance of beneficial bacteria to regulate gut microbiota such as Ruminococcus, Turicibacter, and Parabacteroides, and reduce the abundance of harmful bacteria such as Staphylococcus and Shigella. Furthermore, transcriptomics of colonic mucosal findings point out that the beneficial effect of RRTE on UC could be attributed to the modulation of inflammatory responses such as the IL-17 and TNF signaling pathways. The qPCR results confirm that RRTE did involve the regulation of several genes in the IL-17 signaling pathway. In conclusion, RRTE could prevent DSS-induced damage both in vitro and in vivo.

Egg yolk phosphatidylcholine alleviates DSS-induced colitis in BALB/c mice

Ulcerative colitis (UC) is a common inflammatory bowel disease, whose incidence is on the rise worldwide. The drugs commonly used for UC are often associated with a number of side effects. Therefore, the development of effective, food-borne substances for UC is in line with the current needs. Egg yolk phosphatidylcholine (EYPC) is one of the abundant lipids in egg yolk and possesses various biological activities. However, its protective effect against UC has not been clarified. In this study, the anti-UC activity of EYPC was investigated using a dextran sodium sulfate (DSS)-induced colitis model of BALB/c mice. The results showed that EYPC supplementation inhibited DSS-induced colon shortening, the spleen index and disease activity index increase and intestinal structural damage. EYPC could down-regulate the levels of TNF-α, IL-1β, IL-6 and MPO in the colon and restore the number of goblet cells and the level of tight junction (TJ) proteins. Besides, EYPC modulated the composition of the gut microbiota, lowered the relative abundance of the pathogenic bacterium Parabacteroides and upregulated the abundance of the beneficial bacteria Alistipes and Lachnospiraceae_NK4A136_group. These results evidenced that EYPC could attenuate DSS-induced colitis in mice and had the potential to prevent and treat UC.

20(S)- Protopanaxadiol saponins isolated from Panax notoginseng target the binding of HMGB1 to TLR4 against inflammation in experimental ulcerative colitis

Ulcerative colitis (UC) has emerged as a global healthcare issue due to high prevalence and unsatisfying therapeutic measures. 20(S)- Protopanaxadiol saponins (PDS) from Panax notoginseng with anti-inflammatory properties is a potential anti-colitis agent. Herein, we explored the effects and mechanisms of PDS administration on experimental murine UC. Dextran sulfate sodium-induced murine UC model was employed to investigate anti-colitis effects of PDS, and associated mechanisms were further verified in HMGB1-exposed THP-1 macrophages. Results indicated that PDS administration exerted ameliorative effects against experimental UC. Moreover, PDS administration remarkably downregulated mRNA expressions and productions of related pro-inflammatory mediators, and reversed elevated expressions of proteins related to NLRP3 inflammasome after colitis induction. Furthermore, administration with PDS also suppressed the expression and translocation of HMGB1, interrupting the downstream TLR4/NF-κB pathway. In vitro, ginsenoside CK and 20(S)-protopanaxadiol, the metabolites of PDS, exhibited greater potential in anti-inflammation, and intervened with the TLR4-binding domain of HMGB1 predictably. Expectedly, ginsenoside CK and 20(S)-protopanaxadiol administrations inhibited the activation of TLR4/NF-κB/NLRP3 inflammasome pathway in HMGB1-exposed THP-1 macrophages. Summarily, PDS administration attenuated inflammatory injury in experimental colitis by blocking the binding of HMGB1 to TLR4, majorly attributed to the antagonistic efficacies of ginsenoside CK and 20(S)-protopanaxadiol.

Restoration of dysregulated intestinal barrier and inflammatory regulation through synergistically ameliorating hypoxia and scavenging reactive oxygen species using ceria nanozymes in ulcerative colitis

BACKGROUND

Reactive oxygen species (ROS) overproduction and excessive hypoxia play pivotal roles in the initiation and progression of ulcerative colitis (UC). Synergistic ROS scavenging and generating O₂ could be a promising strategy for UC treatment.

METHODS

Ceria nanozymes (PEG-CNPs) are fabricated using a modified reverse micelle method. We investigate hypoxia attenuating and ROS scavenging of PEG-CNPs in intestinal epithelial cells and RAW 264.7 macrophages and their effects on pro-inflammatory macrophages activation. Subsequently, we investigate the biodistribution, pharmacokinetic properties and long-term toxicity of PEG-CNPs in mice. PEG-CNPs are administered intravenously to mice with 2,4,6-trinitrobenzenesulfonic acid-induced colitis to test their colonic tissue targeting and assess their anti-inflammatory activity and mucosal healing properties in UC.

RESULTS

PEG-CNPs exhibit multi-enzymatic activity that can scavenge ROS and generate O₂, promote intestinal epithelial cell healing and inhibit pro-inflammatory macrophage activation, and have good biocompatibility. After intravenous administration of PEG-CNPs to colitis mice, they can enrich at the site of colonic inflammation, and reduce hypoxia-induced factor-1α expression in intestinal epithelial cells by scavenging ROS to generate O₂, thus further promoting disrupted intestinal mucosal barrier restoration. Meanwhile, PEG-CNPs can effectively scavenge ROS in impaired colon tissues and relieve colonic macrophage hypoxia to suppress the pro-inflammatory macrophages activation, thereby preventing UC occurrence and development.

CONCLUSION

This study has provided a paradigm to utilize metallic nanozymes, and suggests that further materials engineering investigations could yield a facile method based on the pathological characteristics of UC for clinically managing UC.

A Curcumin-Modified Coordination Polymers with ROS Scavenging and Macrophage Phenotype Regulating Properties for Efficient Ulcerative Colitis Treatment

Overexpression of classically activated macrophages (M1) subtypes and assessed reactive oxygen species (ROS) levels are often observed in patients with ulcerative colitis. At present, the treatment system of these two problems has yet to be established. Here, the chemotherapy drug curcumin (CCM) is decorated with Prussian blue analogs in a straightforward and cost-saving manner. Modified CCM can be released in inflammatory tissue (acidic environment), eventually causing M1 macrophages to transform into M2 macrophages and inhibiting pro-inflammatory factors. Co(III) and Fe(II) have abundant valence variations, and the lower REDOX potential in CCM-CoFe PBA enables ROS clearance through multi-nanomase activity. In addition, CCM-CoFe PBA effectively alleviated the symptoms of UC mice induced by DSS and inhibited the progression of the disease. Therefore, the present material may be used as a new therapeutic agent for UC.

A comparative study of the ameliorative effects of hyaluronic acid oligosaccharides and hyaluronic acid on DSS-induced colitis in mice and research on relevant mechanisms

As a dietary supplement, hyaluronic acid (HA) has exhibited appreciable immunomodulatory activity and an ameliorative effect on rodent colitis. However, its high viscosity is not only refractory to absorb through the gut, but also causes flatulence. In contrast to HA, hyaluronic acid oligosaccharides (o-HAs) can overcome the above-mentioned constraints, but their treatment effect still remains ill-defined contemporarily. Herein, the current study intends to compare the modulatory effects of HA and o-HA on colitis and assess the underlying molecular mechanism. We first showed that o-HA had a better preventive effect than HA in alleviating colitis symptoms, as evidenced by lower body weight loss, lower disease activity index scores, a lower inflammatory response (TNF-α, IL-6, IL-1β, p-NF-κB), and more intact colon epithelial integrity in vivo. The best efficiency was observed in the o-HA treated group with a dosage of 30 mg kg^-1. In an in vitro barrier function assay, o-HA exerted a better protective effect on the transepithelial electrical resistance (TEER), FITC permeability, and wound healing and modulated the expression of tight junction (TJ) proteins (ZO-1, occludin) in lipopolysaccharide (LPS)-stimulated Caco-2 cells. In summary, both HA and o-HA showed the potential to reduce inflammation and ameliorate intestinal damage in DSS-induced colitis and LPS-induced inflammation, but o-HA had improved outcomes. The results also provided a glimpse of the latent mechanism by which HA and o-HA enhanced intestinal barrier function via MLCK/p-MLC signaling pathway suppression.

miRNAs as Predictors of Barrier Integrity

The human body has several barriers that protect its integrity and shield it from mechanical, chemical, and microbial harm. The various barriers include the skin, intestinal and respiratory epithelia, blood-brain barrier (BBB), and immune system. In the present review, the focus is on the physical barriers that are formed by cell layers. The barrier function is influenced by the molecular microenvironment of the cells forming the barriers. The integrity of the barrier cell layers is maintained by the intricate balance of protein expression that is partly regulated by microRNAs (miRNAs) both in the intracellular space and the extracellular microenvironment. The detection of changes in miRNA patterns has become a major focus of diagnostic, prognostic, and disease progression, as well as therapy-response, markers using a great variety of detection systems in recent years. In the present review, we highlight the importance of liquid biopsies in assessing barrier integrity and challenges in differential miRNA detection.

Mucoadhesive Hydrogel with Anti-gastric Acid and Sustained-Release Functions for Amelioration of DSS-Induced Ulcerative Colitis

Mucoadhesive hydrogels with multifunctional properties such as gastric acid resistance and sustained drug release in the intestinal tract are highly desirable for the oral treatment of inflammatory bowel diseases (IBDs). Polyphenols are proven to have great efficacies compared with the first-line drugs for IBD treatments. We recently reported that gallic acid (GA) was capable of forming a hydrogel. However, this hydrogel is prone to easy degradation and poor adhesion in vivo. To tackle this problem, the current study introduced sodium alginate (SA) to form a gallic acid/sodium alginate hybrid hydrogel (GAS). As expected, the GAS hydrogel showed excellent antiacid, mucoadhesive, and sustained degradation properties in the intestinal tract. In vitro studies demonstrated that the GAS hydrogel significantly alleviated ulcerative colitis (UC) in mice. The colonic length of the GAS group (7.75 ± 0.38 cm) was significantly longer than that of the UC group (6.12 ± 0.25 cm). The disease activity index (DAI) value of the UC group was (5.5 ± 0.57), which was markedly higher than that of the GAS group (2.5 ± 0.65). The GAS hydrogel also could inhibit the expression of inflammatory cytokines, regulating macrophage polarization and improving the intestinal mucosal barrier functions. All these results indicated that the GAS hydrogel was an ideal candidate for oral treatment of UC.

Anthocyanin extract from black rice attenuates chronic inflammation in DSS-induced colitis mouse model by modulating the gut microbiota

There is substantial evidence for the probiotic activity of anthocyanins, but the relationship between anthocyanins involved in the regulation of microbiota and intestinal inflammation has not been fully elucidated. The aim of this study was to investigate the regulatory effects of black rice anthocyanin extract (BRAE) on intestinal microbiota imbalance in mice with dextran sulfate sodium (DSS)-induced chronic colitis. DSS was added into drinking water to induce a mouse model of chronic experimental colitis, and BRAE was given by gavage (200 mg/kg/day) for 4 weeks. Body weight, fecal viscosity, and hematochezia were monitored during administration. After mice were sacrificed, the serum concentrations of TNF-α and IL-6 were detected by enzyme-linked immunosorbent assay, and the composition of intestinal flora was analyzed by 16S rDNA sequencing. The results showed that BRAE significantly suppressed DSS-induced colonic inflammatory phenotypes and maintained colon length in mice. In addition, BRAE reduced intestinal permeability and improved intestinal barrier dysfunction in mice with colitis. Gut microbiota analysis showed that BRAE significantly improved the imbalance of intestinal microecological diversity caused by DSS, inhibited the increase in the relative abundance of inflammatory bacteria, and promoted the abundance of anti-inflammatory probiotics including Akkermansia spp.

Polyester-based long acting injectables: Advancements in molecular dynamics simulation and technological insights

Long-acting injectable (LAI) delivery technologies have enabled the development of several pharmaceutical products that improve patient health by delivering therapeutics from weeks to months. Over the last decade, due to its good biocompatibility, formulation tunability, wide range of degradation rates, and extensive clinical studies, polyester-based LAI technologies including poly(lactic-co-glycolic acid) (PLGA) have made substantial progress. Herein, we discuss PLGA properties with seminal approaches in the development of LAIs, the role of molecular dynamic simulations of polymer-drug interactions, and their effects on quality attributes. We also outline the landscape of various advanced PLGA-based and a few non-PLGA LAI technologies; their design, delivery, and challenges from laboratory scale to preclinical and clinical use; and commercial products incorporating the importance of end-user preferences.

Targeting pathophysiological changes using biomaterials-based drug delivery systems: A key to managing inflammatory bowel disease

Inflammatory bowel disease (IBD) is a gastrointestinal disorder, affecting about several million people worldwide. Current treatments fail to adequately control some clinical symptoms in IBD patients, which can adversely impact the patient's quality of life. Hence, the development of new treatments for IBD is needed. Due to their unique properties such as biocompatibility and sustained release of a drug, biomaterials-based drug delivery systems can be regarded as promising candidates for IBD treatment. It is noteworthy that considering the pathophysiological changes occurred in the gastrointestinal tract of IBD patients, especially changes in pH, surface charge, the concentration of reactive oxygen species, and the expression of some biomolecules at the inflamed colon, can help in the rational design of biomaterials-based drug delivery systems for efficient management of IBD. Here, we discuss about targeting these pathophysiological changes using biomaterials-based drug delivery systems, which can provide important clues to establish a strategic roadmap for future studies.

"Two-birds-one-stone" colon-targeted nanomedicine treats ulcerative colitis via remodeling immune microenvironment and anti-fibrosis

Dysregulated mucosal immune responses and colonic fibrosis impose two formidable challenges for ulcerative colitis treatment. It indicates that monotherapy could not sufficiently deal with this complicated disease and combination therapy may provide a potential solution. A chitosan-modified poly(lactic-co-glycolic acid) nanoparticle (CS-PLGA NP) system was developed for co-delivering patchouli alcohol and simvastatin to the inflamed colonic epithelium to alleviate the symptoms of ulcerative colitis via remodeling immune microenvironment and anti-fibrosis, a so-called “two-birds-one-stone” nanotherapeutic strategy. The bioadhesive nanomedicine enhanced the intestinal epithelial cell uptake efficiency and improved the drug stability in the gastrointestinal tract. The nanomedicine effectively regulated the Akt/MAPK/NF-κB pathway and reshaped the immune microenvironment through repolarizing M2Φ, promoting regulatory T cells and G-MDSC, suppressing neutrophil and inflammatory monocyte infiltration, as well as inhibiting dendritic cell maturation. Additionally, the nanomedicine alleviated colonic fibrosis. Our work elucidates that the colon-targeted codelivery for combination therapy is promising for ulcerative colitis treatment and to address the unmet medical need.

New Hyaluronic Acid from Plant Origin to Improve Joint Protection—An In Vitro Study

Background: In recent decades, hyaluronic acid (HA) has attracted great attention as a new treatment option for osteoarthritis. Classical therapies are not able to stop the cartilage degeneration process nor do they favor tissue repair. Nowadays, it is accepted that high molecular weight HA can reduce inflammation by promoting tissue regeneration; therefore, the aim of this study was to verify the efficacy of a new high molecular weight HA of plant origin (called GreenIuronic®) in maintaining joint homeostasis and preventing the harmful processes of osteoarthritis. Methods: The bioavailability of GreenIuronic® was investigated in a 3D intestinal barrier model that mimics human oral intake while excluding damage to the intestinal barrier. Furthermore, the chemical significance and biological properties of GreenIuronic® were investigated in conditions that simulate osteoarthritis. Results: Our data demonstrated that GreenIuronic® crosses the intestinal barrier without side effects as it has a chemical–biological profile, which could be responsible for many specific chondrocyte functions. Furthermore, in the osteoarthritis model, GreenIuronic® can modulate the molecular mechanism responsible for preventing and restoring the degradation of cartilage. Conclusion: According to our results, this new form of HA appears to be well absorbed and distributed to chondrocytes, preserving their biological activities. Therefore, the oral administration of GreenIuronic® in humans can be considered a valid strategy to obtain beneficial therapeutic effects during osteoarthritis.

Using Microbiome-Based Approaches to Deprogram Chronic Disorders and Extend the Healthspan following Adverse Childhood Experiences

Adverse childhood experiences (ACEs), which can include child trafficking, are known to program children for disrupted biological cycles, premature aging, microbiome dysbiosis, immune-inflammatory misregulation, and chronic disease multimorbidity. To date, the microbiome has not been a major focus of deprogramming efforts despite its emerging role in every aspect of ACE-related dysbiosis and dysfunction. This article examines: (1) the utility of incorporating microorganism-based, anti-aging approaches to combat ACE-programmed chronic diseases (also known as noncommunicable diseases and conditions, NCDs) and (2) microbiome regulation of core systems biology cycles that affect NCD comorbid risk. In this review, microbiota influence over three key cyclic rhythms (circadian cycles, the sleep cycle, and the lifespan/longevity cycle) as well as tissue inflammation and oxidative stress are discussed as an opportunity to deprogram ACE-driven chronic disorders. Microbiota, particularly those in the gut, have been shown to affect host–microbe interactions regulating the circadian clock, sleep quality, as well as immune function/senescence, and regulation of tissue inflammation. The microimmunosome is one of several systems biology targets of gut microbiota regulation. Furthermore, correcting misregulated inflammation and increased oxidative stress is key to protecting telomere length and lifespan/longevity and extending what has become known as the healthspan. This review article concludes that to reverse the tragedy of ACE-programmed NCDs and premature aging, managing the human holobiont microbiome should become a routine part of healthcare and preventative medicine across the life course.