Colon-targeted drug delivery of polysaccharide-based nanocarriers for synergistic treatment of inflammatory bowel disease: A review

Tailored strategies based on polysaccharide structural and functional properties for nutrients delivery in inflammatory bowel disease

Many food nutrients suffer from a series of limitations such as poor water solubility, low stability and inadequate bioavailability. These challenges can be effectively improved by food-based delivery systems (FDSs). FDSs are a series of functional carriers developed based on food-borne macromolecules. Natural polysaccharides are widely used in FDSs due to their good bioactivity, functional properties, and biocompatibility. The complex structural and physicochemical properties of polysaccharides have led to the extremely diverse development of FDSs based on polysaccharides. This review summarizes the application of natural polysaccharides from different sources in the development of different types of FDSs and their functional properties. It also emphasizes the feasibility and theoretical strategies to tailor satisfactory properties (shape, size, surface charge and targeting properties) of polysaccharides-based oral delivery systems (PODS) based on the diverse structural characteristics (e.g., solubility, ion type, molecular weight) and bioactivities of polysaccharides. PODS are designed to meet the diverse requirements in term of stability, toxicity, adhesion, cellular uptake, retention time and release behavior. This review also discusses the advantages of PODS in addressing nutrient deficiencies in gastrointestinal environment, with a focus on their role in nutritional interventions for inflammatory bowel disease. This review contributed to the development for novel PODS with specific demand.

Nano-targeted delivery system: a promising strategy of anthocyanin encapsulation for treating intestinal inflammation

Anthocyanins are natural flavonoids derived from plants, widely recognized for their health-promoting effects, specifically to treat inflammatory bowel disease (Crohn's disease and ulcerative colitis). However, certain limitations are associated with their use, including instability, low solubility and permeability, poor gastrointestinal digestion, and low bioavailability. In this review, nano-carriers (e.g., liposome, polymersome, exosome, halloysite nanotubes, dendrimer, and nano-niosome, etc.) were summarized as anthocyanins delivery vehicles to treat inflammatory bowel disease. Recent progress on emerging strategies involved surface functionalization, responsive release, magnetic orientation, and self-assembly aggregation to address intestinal inflammation through nano-carriers and potential mechanisms were discussed. Anthocyanins, water-soluble pigments linked by glycoside bonds have attracted attention to alleviate intestinal inflammation related diseases. Anthocyanins can address intestinal inflammation by exerting their health beneficial effects such as anti-oxidative, anti-inflammatory, regulating the intestinal flora, and promoting apoptosis. Moreover, nano-carriers were discussed as oral delivery system for maximized bioefficacy of anthocyanins and to address concerns related to their low solubility and permeability, poor gastrointestinal metabolism, and low bioavailability were discussed. A future perspective is proposed concerning anthocyanin-loaded nano-carriers, different strategies to improve their efficacy, and developing functional food to treat intestinal inflammation.

The major roles of intestinal microbiota and TRAF6/NF-κB signaling pathway in acute intestinal inflammation in mice, and the improvement effect by Hippophae rhamnoides polysaccharide

Acute enteritis, an intestinal disease with intestinal inflammation and injury as the main pathological manifestations. Inhibiting the inflammatory response is critical to the treatment of acute enteritis. Previous studies have shown that the Hippophae rhamnoides polysaccharide (HRP) has strong immune-enhancing effects. However, their functions regarding the intestines and the underlying mechanism are still unclear. In this study, the role of HRP in lipopolysaccharide (LPS)-induced acute enteritis in mice and its related mechanisms are discussed from two aspects: intestinal inflammation and intestinal microbiota. Kunming mice were inoculated with LPS to establish animal models of acute enteritis. The results showed that HRP attenuated the histological damage and maintained the intestine mucosal barrier via up-regulating the expression of occludin, claudin-1, and zona occludens-1 (ZO-1), and suppressing the levels of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β)). The relative mRNA and protein levels of nuclear factor-kappa B p65 (NF-κBp65) and tumor necrosis factor-receptor-associated factor 6 (TRAF6) in the intestine tissues of LPS-induced acute enteritis mice significantly increased, whereas these adverse changes were alleviated in the HRP intervention groups. Notably, HRP may regulate the expression of the TRAF6/NF-κB signaling pathway by affecting the diversity of the intestinal microbiota. Microbiota analysis showed that HRP promoted the proliferation of beneficial bacteria, including Clostridia_UCG-014, Candidatus_Saccharimonas, Lachnospiraceae_NK4A136_group, Bacteroidota, Deferribacterota, and reduced the abundance of Atopostipes, Corynebacterium, Actinobacteriota, and Desulfobacterota. The studies conformed that the gut microbiota is crucial in HRP-mediated immunity regulation. HRP shows great potential as an immune enhancer and a natural medicine for treating intestinal inflammatory diseases.

Recognizing the biological barriers and pathophysiological characteristics of the gastrointestinal tract for the design and application of nanotherapeutics

The gastrointestinal tract (GIT) is an important and complex system by which humans to digest food and absorb nutrients. The GIT is vulnerable to diseases, which may led to discomfort or even death in humans. Therapeutics for GIT disease treatment face multiple biological barriers, which significantly decrease the efficacy of therapeutics. Recognizing the biological barriers and pathophysiological characteristics of GIT may be helpful to design innovative therapeutics. Nanotherapeutics, which have special targeting and controlled therapeutic release profiles, have been widely used for the treatment of GIT diseases. Herein, we provide a comprehensive review of the biological barrier and pathophysiological characteristics of GIT, which may aid in the design of promising nanotherapeutics for GIT disease treatment. Furthermore, several typical diseases of the upper and lower digestive tracts, such as Helicobacter pylori infection and inflammatory bowel disease, were selected to investigate the application of nanotherapeutics for GIT disease treatment.

Ionically assembled hemostatic powders with rapid self-gelation, strong acid resistance, and on-demand removability for upper gastrointestinal bleeding

Upper gastrointestinal bleeding (UGIB) is bleeding in the upper part of the gastrointestinal tract with an acidic and dynamic environment that limits the application of conventional hemostatic materials. This study focuses on the development of N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride/phytic acid (HTCC/PA, HP) powders with fast hemostatic capability and strong acid resistance, for potential applications in managing UGIB. Upon contact with liquids within 5 seconds, HP powders rapidly transform into hydrogels, forming ionic networks through electrostatic interactions. The ionic crosslinking process facilitates the HP powders with high blood absorption (3.4 times of self-weight), sufficient tissue adhesion (5.2 and 6.1 kPa on porcine skin and stomach, respectively), and hemostasis (within 15 seconds for in vitro clotting). Interestingly, the PA imparts the HP powders with strong acid resistance (69.8% mass remaining after 10 days of incubation at pH 1) and on-demand removable sealing while HTCC contributes to fast hemostasis and good wet adhesion. Moreover, the HP powders show good biocompatibility and promote wound healing. Therefore, these characteristics highlight the promising clinical potential of HP powders for effectively managing UGIB.

Advances in carbohydrate-based nanoparticles for targeted therapy of inflammatory bowel diseases: A review

The incidence of inflammatory bowel disease (IBD), a chronic gastrointestinal disorder, is rapidly increasing worldwide. Unfortunately, the current therapies for IBD are often hindered by premature drug release and undesirable side effects. With the advancement of nanotechnology, the innovative targeted nanotherapeutics are explored to ensure the accurate delivery of drugs to specific sites in the colon, thereby reducing side effects and improving the efficacy of oral administration. The emphasis of this review is to summarize the potential pathogenesis of IBD and highlight recent breakthroughs in carbohydrate-based nanoparticles for IBD treatment, including their construction, release mechanism, potential targeting ability, and their therapeutic efficacy. Specifically, we summarize the latest knowledge regarding environmental-responsive nano-systems and active targeted nanoparticles. The environmental-responsive drug delivery systems crafted with carbohydrates or other biological macromolecules like chitosan and sodium alginate, exhibit a remarkable capacity to enhance the accumulation of therapeutic drugs in the inflamed regions of the digestive tract. Active targeting strategies improve the specificity and accuracy of oral drug delivery to the colon by modifying carbohydrates such as hyaluronic acid and mannose onto nanocarriers. Finally, we discuss the challenges and provide insight into the future perspectives of colon-targeted delivery systems for IBD treatment.

Potential of plant-based polysaccharides as therapeutic agents in ulcerogenic diseases of the gastrointestinal tract: A review

In recent years, natural polysaccharides (PSs) have attracted increasing interest because of their remarkable biological properties and potential in various areas, such as medicine, and food. This study aimed to present a detailed review of the evidence on the therapeutic potential of PSs for the treatment of gastrointestinal diseases. The main evidence was correlated with their chemical composition, mechanism of action and therapeutic effect. The main results showed that the action can be attributed to their ability to suppress excessive inflammatory responses, regulating the expression of cytokines and interleukins, reducing intestinal inflammation and promoting wound healing. Furthermore, we discussed how PSs help in the repair of the intestinal mucosa and related these effects with the composition of monosaccharides. A detailed analysis was performed on the ability of PSs to modulate the intestinal microbiota, promoting the growth of beneficial bacteria and suppressing inflammatory bacteria, in addition to its probiotic action with production of short-chain fatty acids. All this evidence was also taken into a broader context, in which the main challenges in processing PSs were considered and strategies to circumvent them were pointed out. Therefore, this review sought to demonstrate the great potential and viability of PSs as innovative and effective therapeutic agents.

Encapsulation of β-Galactosidase into Polyallylamine/Polystyrene Sulphonate Polyelectrolyte Microcapsules

More than half of the global population is unable to consume dairy products due to lactose intolerance (hypolactasia). Current enzyme replacement therapy methods are insufficiently effective as a therapeutic approach to treating lactose intolerance. The encapsulation of β-galactosidase in polyelectrolyte microcapsules by using the layer-by-layer method could be a possible solution to this problem. In this study, adsorption and co-precipitation methods were employed for encapsulating β-galactosidase in polyelectrolyte microcapsules composed of (polyallylamine /polystyrene sulphonate)₃. As a result, the co-precipitation method was chosen for β-galactosidase encapsulation. The adsorption method permits to encapsulate six times less enzyme compared with the co-precipitation method; the β-galactosidase encapsulated via the co-precipitation method released no more than 20% of the initially encapsulated enzyme in pH 2 or 1 M NaCl solutions. In contrast, when using the sorption method, about 100% of the initially encapsulated enzyme was released from the microcapsules under the conditions described above. The co-precipitation method effectively prevents the complete loss of enzyme activity after 2 h of incubation in a solution with pH 2 while also alleviating the adverse effects of ionic strength. Consequently, the encapsulated form of β-galactosidase shows promise as a potential therapeutic agent for enzyme replacement therapy in the treatment of hypolactasia.

Single-cell encapsulation systems for probiotic delivery: Armor probiotics

Functional foods or drugs based on probiotics have gained unprecedented attention and development due to the increasingly clear relationship between probiotics and human health. Probiotics can regulate intestinal microbiota, dynamically participating in various physiological activities to directly affect human health. Some probiotic-based functional preparations have shown great potential in treating multiple refractory diseases. Currently, the survival and activity of probiotic cells in complex environments in vitro and in vivo have taken priority, and various encapsulation systems based on food-derived materials have been designed and constructed to protect and deliver probiotics. However, traditional encapsulation technology cannot achieve precise protection for a single probiotic, which makes it unable to have a significant effect after release. In this case, single-cell encapsulation systems can be assembled based on biological interfaces to protect and functionalize individual probiotic cells, maximizing their physiological activity. This review discussed the arduous challenges of probiotics in food processing, storage, human digestion, and the commonly used probiotic encapsulation system. Besides, a novel technology of probiotic encapsulation was introduced based on single-cell coating, namely, "armor probiotics". We focused on the classification, structural design, and functional characteristics of armor coatings, and emphasized the essential functional characteristics of armor probiotics in human health regulation, including regulating intestinal health and targeted bioimaging and treatment of diseased tissues. Subsequently, the benefits, limitations, potential challenges, as well as future direction of armor probiotics were put forward. We hope this review may provide new insights and ideas for developing a single-cell probiotics encapsulating system.

PepT1-targeted nanodrug based on co-assembly of anti-inflammatory peptide and immunosuppressant for combined treatment of acute and chronic DSS-induced ColitiS

Introduction

Inflammatory bowel disease (IBD), as a chronic and recurrent inflammatory bowel diseases with limited therapeutic outcomes, is characterized by immune disorders and intestinal barrier dysfunction. Currently, the most medications used to cure IBD in clinic just temporarily induce and maintain remission with poor response rates and limited outcomes. Therefore, it is urgently necessary to develop an appropriate therapeutic candidate with preferable efficacy and less adverse reaction for curing IBD.

Methods

Five groups of mice were utilized: control that received saline, DSS group (mice received 2.5% DSS or 4% DSS), KPV group (mice received KPV), FK506 group (mice received FK506) and NPs groups (mice received NPs). The effect of NP on the inflammatory factors of macrophage was evaluated using CCK-8, quantitative polymerase chain reaction (PCR), Elisa and Western blot (WB). Immunofluorescent staining revealed the targeting relationship between NP and Petp-1. Immunohistochemistry staining showed the effect of NP on tight junction proteins. Moreover, in vivo animal experiments confirmed that NPs reduced inflammatory levels in IBD.

Results and Discussion

After administering with NPs, mice with DSS-induced acute or chronic colitis exhibited significant improvement in body weight, colon length, and disease activity index, decreased the level of the factors associated with oxidative stress (MPO, NO and ROS) and the inflammatory cytokines (TNF-α, IL-1β and IL-6), which implied that NPs could ameliorate murine colitis effectively. Furthermore, treating by NPs revealed a notable reduction of the expressions of CD68 and CD3, restoring the expression levels of tight junction proteins (Claudin-5, Occludin-1, and ZO-1) were significantly restored, surpassing those observed in the KPV and FK506 groups. which indicated that NPs can reduce inflammation and enhance epithelial barrier integrity by decreasing the infiltration of macrophages and T-lymphocytes. Collectively, those results demonstrated the effectively therapeutic outcome after using NPs in both acute and chronic colitis, suggesting that the newly co-assembled of NPs can be as a potential therapeutic candidate for colitis.

Resistant starch and tannic acid synergistically ameliorated dextran sulfate sodium-induced ulcerative colitis, particularly in the distal colon

We previously confirmed that tannic acid could delay the metabolism of resistant starch in vitro, which suggested that tannic acid might deliver resistant starch to the distal colon in vivo. Accordingly, co-supplementation of resistant starch and tannic acid might be beneficial for keeping the distal colon healthy. Thus, this study compared the effects of resistant starch, tannic acid and their mixtures on dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. It was found that the mixtures had a more profound effect on ameliorating DSS-induced ulcerative colitis than resistant starch or tannic acid. In particular, the mixtures reversed the histology damage of the distal colon induced by DSS, while resistant starch or tannic acid alone did not. The mixtures also had a stronger ability to resist oxidative stress and inhibit inflammation in the distal colon. These results suggested that resistant starch and tannic acid synergistically alleviated DSS-induced ulcerative colitis, particularly in the distal colon. On the other hand, DSS decreased the production of short-chain fatty acids and induced significant microbial disorder, while the administration of resistant starch, tannic acid and their mixtures reversed the above shifts caused by DSS. In particular, the mixtures exhibited stronger prebiotic activity, as indicated by the microbial composition and production of short-chain fatty acids. Therefore, it was inferred that tannic acid delivered resistant starch to the distal colon of mice, and thus the mixtures had stronger prebiotic activity. As a result, the mixtures effectively alleviated ulcerative colitis in the whole colon.

pH-Sensitive Hydrogels Fabricated with Hyaluronic Acid as a Polymer for Site-Specific Delivery of Mesalamine

Hydrogels with the main objective of releasing mesalamine (5-aminosalicylic acid) in the colon in a modified manner were formulated in the present work using a free-radical polymerization approach. Different ratios of hyaluronic acid were cross-linked with methacrylic and acrylic acids using methylenebis(acrylamide). The development of a new polymeric network and the successful loading of drug were revealed by Fourier transform infrared spectroscopy. Thermogravimetric analysis demonstrated that the hydrogel was more thermally stable than the pure polymer and drug. Scanning electron microscopy (SEM) revealed a rough and hard surface which was relatively suitable for efficient loading of drug and significant penetration of dissolution medium inside the polymeric system. Studies on swelling and drug release were conducted at 37 °C in acidic and basic conditions (pH 1.2, 4.5, 6.8, and 7.4, respectively). Significant swelling and drug release occurred at pH 7.4. Swelling, drug loading, drug release, and gel fraction of the hydrogels increased with increasing hyaluronic acid, methacrylic acid, and acrylic acid concentrations, while the sol fraction decreased. Results obtained from the toxicity study proved the formulated system to be safe for biological systems. The pH-sensitive hydrogels have the potential to be beneficial for colon targeting due to their pH sensitivity and biodegradability. Inflammatory bowel disease may respond better to hydrogel treatment as compared to conventional dosage forms. Specific amount of drug is released from hydrogels at specific intervals to maintain its therapeutic concentration at the required level.

Nanomedicine for colon-targeted drug delivery: strategies focusing on inflammatory bowel disease and colon cancer

The nanostructured drug-delivery systems for colon-targeted drug delivery are a promising field of research for localized diseases particularly influencing the colonic region, in other words, ulcerative colitis, Crohn's disease, and colorectal cancer. There are various drug-delivery approaches designed for effective colonic disease treatment, including stimulus-based formulations (enzyme-triggered systems, pH-sensitive systems) and magnetically driven drug-delivery systems. In addition, targeted drug delivery by means of overexpressed receptors also offers site specificity and reduces drug resistance. It also covers GI tract-triggered emulsifying systems, nontoxic plant-derived nanoformulations as advanced drug-delivery techniques as well as nanotechnology-based clinical trials toward colonic diseases. This review gives insight into advancements in colon-targeted drug delivery to meet site specificity or targeted drug-delivery requirements.

Nanoemulsions Based on Soluble Chenopodin/Alginate Complex for Colonic Delivery of Quercetin

Inflammatory bowel disease (IBD) is an autoimmune disorder caused by uncontrolled immune activation and the subsequent destruction of the colon tissue. Quercetin (Qt) is a natural antioxidant and anti-inflammatory agent proposed as an alternative to mitigate IBD. However, its use is limited by its low oral bioavailability. This study aimed to develop nanoemulsions (NEs) based on a soluble chenopodin/alginate (QPA) complex and Tween 80 (T80), intended for the colonic release of Qt, activated by the pH (5.4) and bacteria present in the human colonic microbiota. NEs with different ratios of QPA/Tw80 (F1-F6) were prepared, where F4Qt (60/40) and F5Qt (70/30) showed sizes smaller than 260 nm, PDI < 0.27, and high encapsulation efficiency (>85%). The stability was evaluated under different conditions (time, temperature, pH, and NaCl). The DSC and FTIR analyses indicated hydrophobic and hydrogen bonding interactions between QPA and Qt. F4Qt and F5Qt showed the greater release of Qt in PBS1X and Krebs buffer at pH 5.4 (diseased condition), compared to the release at pH 7.4 (healthy condition) at 8 h of study. In the presence of E. coli and B. thetaiotaomicron, they triggered the more significant release of Qt (ƒ2 < 50) compared to the control (without bacteria). The NEs (without Qt) did not show cytotoxicity in HT-29 cells (cell viability > 80%) and increased the antioxidant capacity of encapsulated Qt. Therefore, these NEs are promising nanocarriers for the delivery of flavonoids to the colon to treat IBD.

Black rice anthocyanins nanoparticles based on bovine serum albumin and hyaluronic acid: Preparation, characterization, absorption and intestinal barrier function protection in Caco-2 monolayers

Black rice anthocyanins (BRA) nanoparticles (NPs) were prepared using hyaluronic acid (HA), oxidized hyaluronic acid (OHA) and bovine serum albumin (BSA) to enhance the absorption and bioactivity of anthocyanins (ACNs). Results showed that HA/OHA-BSA-BRA NPs had a spherical morphology and excellent dispensability, with hydrated radius ~ 500 nm, zeta potential ~ - 30 mV, and encapsulation efficiency ~21 %. Moreover, using in vitro gastrointestinal release assay, we demonstrated that both BRA-loaded NPs exhibited effective controlled release properties of ACNs, significantly enhancing the accessibility of ACNs to the intestine. Cellular experiments showed that both two NPs had good biocompatibility and increased uptake of BRA. Furthermore, in comparison to the free BRA group, both BRA NPs groups significantly decreased the TEER value and increased the expression of tight junction proteins (Claudin 1, Occludin and ZO-1) in Caco-2 cell monolayers with LPS-induced damage. Therefore, our study demonstrated that HA/OHA-BSA-BRA NPs are promising carriers of ACNs and can effectively prevent the LPS-induced intestinal barrier injury in vitro.

In vitro digestion properties of Laiyang pear residue polysaccharides and it counteracts DSS-induced gut injury in mice via modulating gut inflammation, gut microbiota and intestinal barrier

The aim of this study was to explore the dynamic changes in the physicochemical properties of Laiyang pear residue polysaccharide (LPP) during in vitro digestion, as well as its protective effect on the intestines. Monosaccharide composition and molecular weight analysis showed that there was no significant change in LPP during the oral digestion stage. However, during the gastric and intestinal digestion stages, the glycosidic bonds of LPP were broken, leading to the dissociation of large molecular aggregates and a significant increase in reducing sugar content (CR) accompanied by a decrease in molecular weight. In addition, LPP exerted the intestinal protective ability via inhibiting gut inflammation, improving intestinal barrier, and regulating intestinal flora in DSS-induced mice. Specifically, LPP mitigated DSS-induced intestinal pathological damage of mice via enhancing intestinal barrier integrity and upregulating expressions of TJ proteins, and suppressed inflammation by inhibiting NF-κB signaling axis. Furthermore, LPP decreased the ratio of Firmicutes/Bacteroidetes, increased the relative abundance of Lactobacillus, and altered the diversity and the composition of gut microbiota in DSS-induced mice. Therefore, LPP had the potential to be a functional food that improved gut microbiota environment to enhance health and prevent diseases, such as a prebiotic.

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.

The Effect of Inflammatory Bowel Disease and Irritable Bowel Syndrome on Pravastatin Oral Bioavailability: In vivo and in silico evaluation using bottom-up wbPBPK modeling

The common disorders irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) can modify the drugs' pharmacokinetics via their induced pathophysiological changes. This work aimed to investigate the impact of these two diseases on pravastatin oral bioavailability. Rat models for IBS and IBD were used to experimentally test the effects of IBS and IBD on pravastatin pharmacokinetics. Then, the observations made in rats were extrapolated to humans using a mechanistic whole-body physiologically-based pharmacokinetic (wbPBPK) model. The rat in vivo studies done herein showed that IBS and IBD decreased serum albumin (> 11% for both), decreased PRV binding in plasma, and increased pravastatin absolute oral bioavailability (0.17 and 0.53 compared to 0.01) which increased plasma, muscle, and liver exposure. However, the wbPBPK model predicted muscle concentration was much lower than the pravastatin toxicity thresholds for myotoxicity and rhabdomyolysis. Overall, IBS and IBD can significantly increase pravastatin oral bioavailability which can be due to a combination of increased pravastatin intestinal permeability and decreased pravastatin gastric degradation resulting in higher exposure. This is the first study in the literature investigating the effects of IBS and IBD on pravastatin pharmacokinetics. The high interpatient variability in pravastatin concentrations as induced by IBD and IBS can be reduced by oral administration of pravastatin using enteric-coated tablets. Such disease (IBS and IBD)-drug interaction can have more drastic consequences for narrow therapeutic index drugs prone to gastric degradation, especially for drugs with low intestinal permeability.

Preparation and application of curcumin loaded with citric acid crosslinked chitosan-gelatin hydrogels

While oral administration offers safety benefits, its therapeutic efficacy is hindered by various physiological factors within the body. In this study, a novel approach was explored using a matrix consisting of 2 % chitosan and 2 % gelatin, with citric acid (CA) serving as a green cross-linking agent (ranging from 0.4 % to 1.0 %), and curcumin (Cur) as the model drug to formulate hydrogel carriers. The results showed that a 0.4 % CA concentration, the hydrogel (CGA0.4) reached swelling equilibrium in deionized water within 40 min, exhibiting a maximum swelling index was 539 g/g. The addition of Cur to the CGA hydrogel (CGACur) notably enhanced release efficiency, particularly in simulated intestinal fluid, where Cur release rates exceeded 40 % within 100 min compared to below 8 % in other solutions. Among these hydrogels, CGA0.4Cur exhibited the fastest degradation rate in the combined solution, reaching >90 % degradation after 7 days. Additionally, Cur and CA demonstrated positive effects on the tensile strength, antioxidant activity and antibacterial activity of hydrogels. Compare to the bioaccessibility of CGC (27 %), those of CGACur had increased to over 34 %. These findings offer provide theoretical support for CA-crosslinked chitosan/gelatin gels in delivering hydrophobic bioactive molecules and their application in intestinal drug delivery system.

Modulating Effects of Turmeric Polysaccharides on Immune Response and Gut Microbiota in Cyclophosphamide-Treated Mice

Turmeric, a traditional medicinal herb, is commonly used as a dietary and functional ingredient. This study aimed to investigate the effect of turmeric polysaccharides (TPs) on intestinal immunity and gut microbiota in cyclophosphamide (Cy)-induced immunosuppressed BALB/c mice. We verified that the oral administration of TPs-0 and TPs-3 (200 and 400 mg/kg, bw) improved thymus and spleen indexes, increased the whole blood immune cells (WBC) and lymph count index, and stimulated the secretion of serum immunoglobulin IgG. More importantly, TPs-0 and TPs-3 could repair intestinal immune damage and reduce intestinal inflammation. The specific mechanism is ameliorating the intestinal pathological damage, promoting CD4+ T cell secretion, regulating the expression of related cytokines, and reducing the level of critical proteins in the NF-κB/iNOS pathway. Interestingly, the intake of TPs-0 and TPs-3 significantly increased the content of short-chain fatty acids (SCFAs). Moreover, TPs-0 and TPs-3 relieved the intestinal microbiota disorder via the proliferation of the abundance of Lactobacillus and Bacteroides and the inhibition of Staphylococcus. Cumulatively, our study suggests that TPs-0 and TPs-3 can relieve intestinal immune damage by repairing the immune barrier and regulating intestinal flora disorders. TPs have potential applications for enhancing immunity as a functional food.

The European Polysaccharide Network of Excellence (EPNOE) research roadmap 2040: Advanced strategies for exploiting the vast potential of polysaccharides as renewable bioresources

Polysaccharides are among the most abundant bioresources on earth and consequently need to play a pivotal role when addressing existential scientific challenges like climate change and the shift from fossil-based to sustainable biobased materials. The Research Roadmap 2040 of the European Polysaccharide Network of Excellence (EPNOE) provides an expert's view on how future research and development strategies need to evolve to fully exploit the vast potential of polysaccharides as renewable bioresources. It is addressed to academic researchers, companies, as well as policymakers and covers five strategic areas that are of great importance in the context of polysaccharide related research: (I) Materials & Engineering, (II) Food & Nutrition, (III) Biomedical Applications, (IV) Chemistry, Biology & Physics, and (V) Skills & Education. Each section summarizes the state of research, identifies challenges that are currently faced, project achievements and developments that are expected in the upcoming 20 years, and finally provides outlines on how future research activities need to evolve.

Phyllanthus emblica L. polysaccharides ameliorate colitis via microbiota modulation and dual inhibition of the RAGE/NF-κB and MAPKs signaling pathways in rats

Pharmacological treatments for colitis have limited efficacy and side effects. Plant polysaccharides improve colitis by modulating the gut microbiota. However, the specific benefits of Phyllanthus emblica L. polysaccharides (PEPs) in colitis remain unclear. Therefore, this study aimed to assess the physical characteristics and health advantages of PEP in rats subjected to 2,4,6-trinitrobenzene sulfonic acid (TNBS) treatment. The results showed that PEP (1.226 × 103 kDa) was an α-acidic pyran heteropolysaccharide rich in galactose and galacturonic acid. Prefeeding rats with PEP significantly decreased the levels of NO, MDA, proinflammatory cytokines (IL-6, IL-1β, TNF-α), apoptosis, and the activities of mucinase and β-glucuronidase. These changes were accompanied by increases in the levels of anti-inflammatory cytokines (IL-4, IL-10) and antioxidant enzymes (SOD, catalase, GPx) in colitis rats. Mechanistically, PEP suppressed the abundance of inflammatory-related bacteria (Bacteroides, Intestinimonas, and Parabacteroides) while promoting the growth of short-chain fatty acid (SCFA)-producing bacteria (Romboutsia, Clostridium_sensu_stricto_1, and Lactobacillus), along with an increase in SCFA secretion. SCFAs may engage with the GPR43 receptor and inhibit downstream HDAC3, consequently downregulating the activation of the RAGE/NF-κB and MAPK pathways. In conclusion, PEP demonstrated preventive effects through its antioxidant, anti-inflammatory, and microbiota modulation properties, thereby ameliorating TNBS-induced colitis in rats.

Soluble dietary fibers from solid-state fermentation of wheat bran by the fungus Cordyceps cicadae and their effects on colitis mice

Ulcerative colitis is a chronic inflammatory disease with a complex pathogenesis for which there is no definitive therapeutic agent. Fermentation, as a green and efficient bioprocessing technique, has been shown to enhance the biological activity of food ingredients. Soluble dietary fiber isolated from plants is thought to have the potential to prevent and alleviate ulcerative colitis. This work was designed to study the differences in the chemical properties of the soluble dietary fiber from wheat bran fermented by Isaria cicadae Miq. (FSDF) and the unfermented soluble dietary fiber from wheat bran (UFSDF) and their effects on colitis mice. The results showed that FSDF and UFSDF differed in molecular weight, monosaccharide compositions, and surface morphology. In addition, supplementation with UFSDF and FSDF ameliorated the symptoms of DSS-induced colitis in mice by attenuating body weight loss, decreasing the disease activity index and splenic index, shortening the length of the colon, and attenuating colonic tissue damage. UFSDF and FSDF also increased the production of the anti-inflammatory cytokine IL-10 and inhibited the expression of IL-6, IL-1β, and TNF-α. The results of gut flora and short-chain fatty acid analyses showed that UFSDF and FSDF improved the diversity of gut microbiota, up-regulated the abundance of some beneficial bacteria such as Akkermansia and Muribaculaceae, increased the levels of acetic acid, propionic acid, and butyric acid, and restored dextran sodium sulfate (DSS)-induced dysbiosis of the intestinal flora in mice. These findings provide guidance for the development of FSDF and UFSDF as functional foods for the relief of ulcerative colitis.

Citrus peel pectin and alginate-based emulgel particles for small intestine-targeted oral delivery of curcumin

Polysaccharides are a prominent choice in the realm of food-grade oral delivery systems due to their resistance to degradation by digestive enzymes in the oral, gastric, and small intestinal environments, as well as their ease of production, cost-effectiveness, and potential health benefits as prebiotics. Furthermore, their ability to respond to pH-induced dissolution, along with their emulsifying properties, can be strategically employed to achieve precise targeting of lipophilic bioactives to the small intestine. In this study, citrus peel pectin and alginate served as stabilizers for emulgel particles without supplementary emulsifiers or gelling agents. Within this system, pectin functioned as an emulsifier, while alginate acted as a gelling agent, facilitated by Ca2+-induced ionic crosslinking. The synergistic interplay between pectin and alginate efficiently protected curcumin in gastric conditions and controlled dissolution in the small intestine, depending on the pectin/alginate ratio. These controlled phenomena facilitated lipolysis, curcumin release, and ultimately enhanced curcumin bioaccessibility. Furthermore, once the emulgel particle released all the entrapped curcumin in the small intestine, residual polysaccharides underwent facile degradation by pectinase and alginate lyase, yielding fermentable monosaccharides. This confirms the potential of the emulgel particles for use as a prebiotic in the colon. These findings offer significant promise for enhancing the systematic design of food-grade delivery systems that encapsulate lipophilic bioactives, achieving controlled release, enhanced stability, and improved bioaccessibility. Importantly, this system can comprise components that undergo complete digestion, absorption, and utilization in the human body, encompassing materials such as oil, nutraceuticals, and prebiotics, all without presenting health risks.

An efficient co-delivery system based on multilayer structural nanoparticles for programmed sequential release of resveratrol and vitamin D3 to combat dextran sodium sulfate-induced colitis in mice

Multilayer structural nanoparticles (MSNPs) fabricated by layer-by-layer self-assembly were used for the co-encapsulation of resveratrol (Res) and vitamin D3 (Vd). Res and Vd co-encapsulated MSNPs (Res-Vd-MSNPs) were evaluated by appearance, morphology, particle size, ζ potential and encapsulation efficiency (EE). The results showed that Res-Vd-MSNPs were spherical in shape with a particle size of 625.4 nm and a surface charge of +26.1 mV. The EE of Res and Vd was as high as 93.6 % and 90.8 %, respectively. Res-Vd-MSNPs exhibited better stability and lower degradation rate in simulated gastric fluid, allowing the programmed sequential release of Vd and Res in simulated intestinal fluid and simulated colonic fluid, which was also confirmed by in vivo fluorescence imaging of mice. In addition, Res-Vd-MSNPs effectively alleviated the clinical symptoms of dextran sulfate sodium salt (DSS)-induced colitis in mice, including weight loss, diarrhea and fecal bleeding, and it especially exerted a preventive effect on DSS-induced colon tissue damage and colon shortening. Furthermore, Res-Vd-MSNPs suppressed the expression of anti-inflammatory cytokines such as TNF-α, IL-1β and IL-6 and ameliorated DSS-induced oxidative damage, decreased colonic myeloperoxidase (MPO) and nitric oxide (NO) activities and elevated glutathione (GSH) level in DSS-treated mice. This study illustrated that MSNPs were potential carriers for developing the co-delivery system for the synergistic prevention and treatment of ulcerative colitis.

Classification and design strategies of polysaccharide-based nano-nutrient delivery systems for enhanced bioactivity and targeted delivery: A review

Since many nutrients are highly sensitive, they cannot be absorbed and utilized efficiently by the body. Using nano-delivery systems to encapsulate nutrients is an effective method of solving the problems associated with the application of nutrients at this stage. Polysaccharides, as natural biomaterials, have a unique chemical structure, ideal biocompatibility, biodegradability and low immunogenicity. This makes polysaccharides powerful carriers that can enhance the biological activity of nutrients. However, the true role of polysaccharide-based delivery systems requires an in-depth understanding of the structural and physicochemical characteristics of polysaccharide-based nanodelivery systems, as well as effective modulation of the intestinal delivery mechanism and the latest advances in nano-encapsulation. This review provides an overview of polysaccharide-based nano-delivery systems dependent on different carrier types, emphasizing recent advances in the application of polysaccharides, a biocomposite material designed for nutrient delivery systems. Strategies for polysaccharide-based nano-delivery systems to enhance the bioavailability of orally administered nutrients from the perspective of the intestinal absorption barrier are presented. Characterization methods for polysaccharide-based nano-delivery systems are presented as well as an explanation of the formation mechanisms behind nano-delivery systems from the perspective of molecular forces. Finally, we discussed the challenges currently facing polysaccharide-based nano-delivery systems as well as possible future directions for the future.

Protein/polysaccharide-based hydrogels loaded probiotic-mediated therapeutic systems: A review

The natural characteristics of protein/polysaccharide-based hydrogels, as a potential drug delivery platform, have attracted extensive attention. Probiotics have attracted renewed interest in drug research because of their beneficial effects on host health. The idea of using probiotics loaded on protein/polysaccharide-based hydrogels as potential drugs to treat different diseases has been put forward and shows great prospects. Based on this, in this review, we highlight the design strategy of hydrogels loaded probiotic-mediated therapy systems and review the potential diseases that have been proved to be treatable in the laboratory, including promoting wound healing and improving intestinal health and vaginal health, and discuss the challenges existing in the current design.

Inhibition of IEC-6 Cell Proliferation and the Mechanism of Ulcerative Colitis in C57BL/6 Mice by Dandelion Root Polysaccharides

An exploration was conducted on the potential therapeutic properties of dandelion polysaccharide (DP) in addressing 3% dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) in murine models. Subsequent assessments focused on DP's influence on inflammation, oxidative stress, and ferroptosis in IEC-6 cells damaged by H2O2. Results highlighted the efficacy of DP in mitigating weight loss, improving disease activity index scores, normalizing colon length, and alleviating histological abnormalities in the affected mice. DP repaired colonic mitochondrial damage by enhancing iron transport and inhibited iron death in colonic cells. Moreover, DP played a pivotal role in enhancing the antioxidant potential. This was evident from the increased expression levels of Nrf2, HO-1, NQO-1, and GSH, coupled with a decrease in MDA and 4-HNE markers in the UC-afflicted mice. Concurrently, DP manifested inhibitory effects on MPO activation and transcription levels of inflammatory mediators such as IL-1β, IL-6, TNF-α, and iNOS. An upsurge in the expression of occludin and ZO-1 was also observed. Restoration of intestinal tightness resulted in decreased serum LPS and LDH levels. Thereafter, administration of DP by gavage increased fecal flora diversity and relative abundance of probiotics in UC mice. Analysis of metabolites indicated that DP counteracted metabolic disturbances and augmented the levels of short-chain fatty acids in ulcerative colitis-affected mice. In vitro studies underscored the role of DP in triggering Nrf2 activation, which in turn exhibited anti-inflammatory, antioxidant, and anti-ferroptotic properties. Summarily, DP's capacity to activate Nrf2 contributes to the suppression of ferroptotic processes in intestinal epithelial cells of UC-affected mice, enhancing the intestinal barrier's integrity. Beyond that, DP possesses the ability to modulate the gut microbiome, rectify metabolic imbalances, rejuvenate short-chain fatty acid levels, and bolster the intestinal barrier as a therapeutic approach to UC.

pH stimuli-responsive hydrogels from non-cellulosic biopolymers for drug delivery

Over the past several decades, there has been significant growth in the design and development of more efficient and advanced biomaterials based on non-cellulosic biological macromolecules. In this context, hydrogels based on stimuli-responsive non-cellulosic biological macromolecules have garnered significant attention because of their intrinsic physicochemical properties, biological characteristics, and sustainability. Due to their capacity to adapt to physiological pHs with rapid and reversible changes, several researchers have investigated pH-responsive-based non-cellulosic polymers from various materials. pH-responsive hydrogels release therapeutic substances in response to pH changes, providing tailored administration, fewer side effects, and improved treatment efficacy while reducing tissue damage. Because of these qualities, they have been shown to be useful in a wide variety of applications, including the administration of chemotherapeutic drugs, biological material, and natural components. The pH-sensitive biopolymers that are utilized most frequently include chitosan, alginate, hyaluronic acid, guar gum, and dextran. In this review article, the emphasis is placed on pH stimuli-responsive materials that are based on biological macromolecules for the purposes of drug administration.

Research progress of colon-targeted oral hydrogel system based on natural polysaccharides

The quality of life is significantly impacted by colon-related diseases. There have been a lot of interest in the oral colon-specific drug delivery system (OCDDS) as a potential carrier to decrease systemic side effects and protect drugs from degradation in the upper gastrointestinal tract (GIT). Hydrogels are effective oral colon-targeted drug delivery carriers due to their high biodegradability, substantial drug loading, and great biocompatibility. Natural polysaccharides give the hydrogel system unique structure and function to effectively respond to the complex environment of the GIT and deliver drugs to the colon. In this paper, the physiological factors of colonic drug delivery and the pathological characteristics of common colonic diseases are summarized, and the latest advances in the design, preparation and characterization of natural polysaccharide hydrogels are reviewed, which are expected to provide new references for colon-targeted oral hydrogel systems using natural polysaccharides as raw materials.

Progress and prospects of polysaccharide-based nanocarriers for oral delivery of proteins/peptides

The oral route has long been recognized as the most preferred route for drug delivery as it offers high patient compliance and requires minimal expertise. Unlike small molecule drugs, the harsh environment of the gastrointestinal tract and low permeability across the intestinal epithelium make oral delivery extremely ineffective for macromolecules. Accordingly, delivery systems that are rationally constructed with suitable materials to overcome barriers to oral delivery are exceptionally promising. Among the most ideal materials are polysaccharides. Depending on the interaction between polysaccharides and proteins, the thermodynamic loading and release of proteins in the aqueous phase can be realized. Specific polysaccharides (dextran, chitosan, alginate, cellulose, etc.) endow systems with functional properties, including muco-adhesiveness, pH-responsiveness, and prevention of enzymatic degradation. Furthermore, multiple groups in polysaccharides can be modified, which gives them a variety of properties and enables them to suit specific needs. This review provides an overview of different types of polysaccharide-based nanocarriers based on different kinds of interaction forces and the influencing factors in the construction of polysaccharide-based nanocarriers. Strategies of polysaccharide-based nanocarriers to improve the bioavailability of orally administered proteins/peptides were described. Additionally, current restrictions and future trends of polysaccharide-based nanocarriers for oral delivery of proteins/peptides were also covered.

Development of Phytochemical Delivery Systems by Nano-Suspension and Nano-Emulsion Techniques

The awareness of the existence of plant bioactive compounds, namely, phytochemicals (PHYs), with health properties is progressively expanding. Therefore, their massive introduction in the normal diet and in food supplements and their use as natural therapeutics to treat several diseases are increasingly emphasized by several sectors. In particular, most PHYs possessing antifungal, antiviral, anti-inflammatory, antibacterial, antiulcer, anti-cholesterol, hypoglycemic, immunomodulatory, and antioxidant properties have been isolated from plants. Additionally, their secondary modification with new functionalities to further improve their intrinsic beneficial effects has been extensively investigated. Unfortunately, although the idea of exploiting PHYs as therapeutics is amazing, its realization is far from simple, and the possibility of employing them as efficient clinically administrable drugs is almost utopic. Most PHYs are insoluble in water, and, especially when introduced orally, they hardly manage to pass through physiological barriers and scarcely reach the site of action in therapeutic concentrations. Their degradation by enzymatic and microbial digestion, as well as their rapid metabolism and excretion, strongly limits their in vivo activity. To overcome these drawbacks, several nanotechnological approaches have been used, and many nanosized PHY-loaded delivery systems have been developed. This paper, by reporting various case studies, reviews the foremost nanosuspension- and nanoemulsion-based techniques developed for formulating the most relevant PHYs into more bioavailable nanoparticles (NPs) that are suitable or promising for clinical application, mainly by oral administration. In addition, the acute and chronic toxic effects due to exposure to NPs reported so far, the possible nanotoxicity that could result from their massive employment, and ongoing actions to improve knowledge in this field are discussed. The state of the art concerning the actual clinical application of both PHYs and the nanotechnologically engineered PHYs is also reviewed.

Drug-Loaded Silver Nanoparticles-A Tool for Delivery of a Mebeverine Precursor in Inflammatory Bowel Diseases Treatment

Chronic, multifactorial illnesses of the gastrointestinal tract include inflammatory bowel diseases. One of the greatest methods for regulated medicine administration in a particular region of inflammation is the nanoparticle system. Silver nanoparticles (Ag NPs) have been utilized as drug delivery systems in the pharmaceutical industry. The goal of the current study is to synthesize drug-loaded Ag NPs using a previously described 3-methyl-1-phenylbutan-2-amine, as a mebeverine precursor (MP). Methods: A green, galactose-assisted method for the rapid synthesis and stabilization of Ag NPs as a drug-delivery system is presented. Galactose was used as a reducing and capping agent forming a thin layer encasing the nanoparticles. Results: The structure, size distribution, zeta potential, surface charge, and the role of the capping agent of drug-loaded Ag NPs were discussed. The drug release of the MP-loaded Ag NPs was also investigated. The Ag NPs indicated a very good drug release between 80 and 85%. Based on the preliminary results, Ag NPs might be a promising medication delivery system for MP and a useful treatment option for inflammatory bowel disease. Therefore, future research into the potential medical applications of the produced Ag NPs is necessary.

Electrospinning and Electrospraying: Emerging Techniques for Probiotic Stabilization and Application

Probiotics are beneficial for human health. However, they are vulnerable to adverse effects during processing, storage, and passage through the gastrointestinal tract, thus reducing their viability. The exploration of strategies for probiotic stabilization is essential for application and function. Electrospinning and electrospraying, two electrohydrodynamic techniques with simple, mild, and versatile characteristics, have recently attracted increased interest for encapsulating and immobilizing probiotics to improve their survivability under harsh conditions and promoting high-viability delivery in the gastrointestinal tract. This review begins with a more detailed classification of electrospinning and electrospraying, especially dry electrospraying and wet electrospraying. The feasibility of electrospinning and electrospraying in the construction of probiotic carriers, as well as the efficacy of various formulations on the stabilization and colonic delivery of probiotics, are then discussed. Meanwhile, the current application of electrospun and electrosprayed probiotic formulations is introduced. Finally, the existing limitations and future opportunities for electrohydrodynamic techniques in probiotic stabilization are proposed and analyzed. This work comprehensively explains how electrospinning and electrospraying are used to stabilize probiotics, which may aid in their development in probiotic therapy and nutrition.

Surface-anchored microbial enzyme-responsive solid lipid nanoparticles enabling colonic budesonide release for ulcerative colitis treatment

Colon-targeted oral drug delivery systems (CDDSs) are desirable for the treatment of ulcerative colitis (UC), which is a disease with high relapse and remission rates associated with immune system inflammation and dysregulation localized within the lining of the large bowel. However, the success of current available approaches used for colon-targeted therapy is limited. Budesonide (BUD) is a corticosteroid drug, and its rectal and oral formulations are used to treat UC, but the inconvenience of rectal administration and the systemic toxicity of oral administration restrict its long-term use. In this study, we designed and prepared colon-targeted solid lipid nanoparticles (SLNs) encapsulating BUD to treat UC by oral administration. A negatively charged surfactant (NaCS-C12) was synthesized to anchor cellulase-responsive layers consisting of polyelectrolyte complexes (PECs) formed by negatively charged NaCS and cationic chitosan onto the SLNs. The release rate and colon-specific release behavior of BUD could be easily modified by regulating the number of coated layers. We found that the two-layer BUD-loaded SLNs (SLN-BUD-2L) with a nanoscale particle size and negative zeta potential showed the designed colon-specific drug release profile in response to localized high cellulase activity. In addition, SLN-BUD-2L exhibited excellent anti-inflammatory activity in a dextran sulfate sodium (DSS)-induced colitis mouse model, suggesting its potential anti-UC applications.

A comprehensive review on pharmaceutical uses of plant-derived biopolysaccharides

Biopolysaccharides extracted from plants are mainly photosynthetic byproducts found in leaves, pods, stems, fruits, grains, seeds, corms, rhizomes, roots, bark exudates, and other plant parts. Recently, these plant-derived biopolysaccharides have received a great deal of attention as pharmaceutical excipients in a range of different dosage forms because of several key advantages, such as widespread accessibility from nature as plant-based sources are readily available, sustainable production, availability of easy and cost-effective extraction methodologies, aqueous solubility, swelling capability in the aqueous medium, non-toxicity, biodegradability, etc. The current review presents a comprehensive overview of the uses of plant-derived biopolysaccharides as effective pharmaceutical excipients in the formulations of different kinds of dosage forms, for example gels, pastes, films, emulsions, suspensions, capsules, tablets, nanoparticles, microparticles, beads, buccal formulations, transdermal formulations, ocular formulations, nasal formulations, etc.

Folic acid-modified lactoferrin nanoparticles coated with a laminarin layer loaded curcumin with dual-targeting for ulcerative colitis treatment

Curcumin (CUR) is a promising natural compound in ulcerative colitis (UC) treatment, but limited by its low oral bioavailability and poor targeting ability. Therefore, given the targeting action of lactoferrin (LF) by binding to the LF receptors of intestinal epithelial cells (IECs) and of folic acid (FA) by binding to the FA receptors of macrophages, we developed an oral dual-targeting nanosystem. Laminarin (LA)-coated, FA-modified LF nanoparticles (NPs) were used to encapsulate CUR (LA/FA/CUR-NPs) with a food-grade, enzyme-sensitive, and dual-targeting capacity. For the generated NPs, LF improved the loading efficiency of CUR (95.08 %). The LA layer could improve the upper gastrointestinal tract stability of the NPs while improve drug release around colon lesion through β-glucanase digestion. Based on the cellular uptake evaluation, FA/CUR-NPs were capable of specifically targeting colonic epithelial cells and macrophages through LF and FA ligands, respectively, to enhance the uptake efficiency. Moreover, based on the advantage of the dual-targeting strategy, oral administration of FA/CUR-NPs obviously reduced colitis symptoms by alleviating inflammation, accelerating colonic mucosal barrier repair and restoring the balance of the intestinal microbiota. This dual-targeted nanodesign corresponded to the multi-bioresponsibilities of CUR, thus offering a promising approach in UC treatment.

A mesoporous polydopamine-derived nanomedicine for targeted and synergistic treatment of inflammatory bowel disease by pH-Responsive drug release and ROS scavenging

Repurposing clinically approved drugs to construct novel nanomedicines is currently a very attractive therapeutic approach. Selective enrichment of anti-inflammatory drugs and reactive oxygen species (ROS) scavenging at the region of inflammation by stimuli-responsive oral nanomedicine is an effective strategy for the treatment of inflammatory bowel disease (IBD). This study reports a novel nanomedicine, which is based on the excellent drug loading and free radical scavenging ability of mesoporous polydopamine nanoparticles (MPDA NPs). By initiating polyacrylic acid（PAA）polymerization on its surface, a "core-shell" structure nano-carrier with pH response is constructed. Then, under alkaline conditions, using the π-π stacking and hydrophobic interaction between the anti-inflammatory drug sulfasalazine (SAP) and MPDA, the nanomedicines (PAA@MPDA-SAP NPs) loaded efficiently (928 μ g mg^-1) of SAP was successfully formed. Our results reveal that PAA@MPDA-SAP NPs can pass through the upper digestive tract smoothly and finally accumulate in the inflamed colon. Through the synergistic effect of anti-inflammation and antioxidation, it can effectively reduce the expression of pro-inflammatory factors and enhance the intestinal mucosal barrier, and finally significantly alleviate the symptoms of colitis in mice. Furthermore, we confirmed that PAA@MPDA-SAP NPs have good biocompatibility and anti-inflammatory repair ability under inflammation induction through human colonic organoids. In summary, this work provides a theoretical basis for the development of nanomedicines for IBD therapy.

Mucosal Genes Expression in Inflammatory Bowel Disease Patients: New Insights

Individual differences in IBD illness severity, behavior, progression, and therapy response are evident. Since a break in the intestinal epithelial barrier causes IBD to begin, mucosal gene expression in IBD is crucial. Due to its high sensitivity and dynamic nature, molecular analysis of biomarkers in intestinal biopsies is feasible and provides a reliable means of evaluating localized inflammation. The goal of this investigation was to discover alterations in gene expression in the inflamed mucosa of IBD patients undergoing treatment with 5-amino salicylic acid (5ASA) (N = 39) or anti-TNF drugs (N = 22). The mucosal expression of numerous IBD-related genes was evaluated using qPCR. We discovered that the levels of the proteins Lipocalin-2 (LCN2), Nitric Oxide Synthase 2 (NOS2), Mucin 2 (MUC2), Mucin 5AC (MUC5AC), and Trefoil factor 1 (TFF1), which are overexpressed in untreated IBD patients compared to non-IBD subjects, are decreased by both therapy regimens. On the other hand, anti-TNF medicine helped the levels of ABCB1 and E-cadherin return to normal in IBD patients who were not receiving treatment.

Harnessing polymer-derived drug delivery systems for combating inflammatory bowel disease

The inflammatory bowel disease (IBD) is incurable, chronic, recrudescent disorders in the inflamed intestines. Current clinic treatments are challenged by systemic exposure-induced severe side effects, inefficiency after long-term treatment, and increased risks of infection and malignancy due to immunosuppression. Fortunately, naturally bioactive small molecules, reactive oxygen species scavengers (or antioxidants), and gut microbiota modulators have emerged as promising candidates for the IBD treatment. Polymeric systems have been engineered as a delivery vehicle to improve the bioavailability and efficacy of these therapeutic agents through targeting the mucosa and enhancing intestinal adhesion and retention, and reduce their systemic toxicity. Herein we survey polymer-derived drug delivery systems for combating the IBD. Advanced delivery technologies, therapeutic intervention strategies, and the principles for the construction of hierarchical, mucosa-targeting, and bioresponsive systems are elaborated, providing insights into design and development of from-bench-to-bedside drug delivery polymeric systems for the IBD treatment.

Ameliorative effect of buckwheat polysaccharides on colitis via regulation of the gut microbiota

Plant polysaccharides act as prebiotics by modulating gut microbiota. However, the functional characteristics of buckwheat Fagopyrum tataricum polysaccharides (FTP) and F. esculentum polysaccharides (FEP) on colitis prevention are not valid. This study evaluated the ameliorative effects of FTP and FEP against TNBS-induced colitis via gut microbiota modulation in rats. The characterizations of FTP and FEP were analyzed, including FTIR, TGA, DSC, and monosaccharide composition. In addition, the pathological features of colon length and symptoms in TNBS-induced colitis were improved via the intragastric preadministration of FTP and FEP. The results showed that prefeeding with FTP and FEP decreased inflammatory cytokines (IL-6, IL-1β, and TNF-α), β-glucuronidase, and mucinase, as well as increasing superoxide dismutase, catalase, and glutathione peroxidase levels, in TNBS-induced rats. A decrease in inflammatory signaling-associated proteins (NF-κB, MAPK, COX-2, and iNOS) improved the treatment of TNBS-induced colitis by buckwheat polysaccharides. Moreover, prefeeding with buckwheat polysaccharides increased the Firmicutes/Bacteroidetes ratio and short-chain fatty acid (SCFA) production and decreased the abundance of inflammation-related bacteria (Oscillospiraceae and Oscillibacter). In conclusion, FTP and FEP strongly improved TNBS-induced colitis through antioxidant, anti-inflammatory, and microbiota modulation properties, especially in the high-dose FEP group. Buckwheat polysaccharides have the potential for utilization in functional ingredients or food development.

Advancement in Therapeutic Intervention of Prebiotic-Based Nanoparticles for Colonic Diseases

Intestinal flora has become a therapeutic target for the intervention of colonic diseases (CDs) with better understanding of the interplay between microbiota and CDs. Depending on unique properties and prominent ability of regulating the intestinal flora, prebiotics can not only achieve a colon-specific drug delivery but also maintain the intestinal homeostasis, thus playing a positive role in the intervention of CDs. Currently, different studies on prebiotic-based nanoparticles have been contrived for colonic drug delivery and have shown great potential in curing various CDs, such as colitis and colorectal cancer. Nevertheless, there is a lack of systematic survey on the use of prebiotic nanoparticles for the treatment of CDs. This review aims to generalize the state-of-the-art of prebiotic nanomedicines specific for CDs. The species and function of intestinal flora and various kinds of prebiotics available as well as their regulating effects on intestinal flora were expounded. A variety of prebiotic nanoparticles pertinent to colon-targeted drug delivery systems were illustrated with particular emphasis on their curative activities on CDs. The efficacy and safety of prebiotic-based colonic drug delivery systems (p-CDDs) were also analyzed. In conclusion, the synergy between prebiotic nanoparticles and their cargos may hold promise for the treatment and intervention of CDs.

Acid-Resistant Mesoporous Metal-Organic Frameworks as Carriers for Targeted Hypoglycemic Peptide Delivery: Peptide Encapsulation, Release, and Bioactivity

Oral administration of bioactive peptides with α-glucosidase inhibitory activities is a promising strategy for diabetes mellitus. The wheat germ peptide Leu-Asp-Leu-Gln-Arg (LDLQR) has been previously proven to inhibit the activity of α-glucosidase efficiently. However, it is still difficult to transport the peptide to the intestine completely due to the harsh condition of the stomach. Herein, an acid-resistant zirconium-based metal-organic framework, NU-1000, was used to immobilize LDLQR with a high encapsulation capacity (92.72%) and encapsulation efficiency (44.08%) in only 10 min. The in vitro release results showed that the acid-stable NU-1000 not only effectively protected LDLQR from degradation in the presence of stomach acid and pepsin effectively but also ensured the release of encapsulated LDLQR under simulated intestinal conditions. Furthermore, LDLQR@NU-1000 could slow down the elevated blood sugar caused by maltose in mice and the area under blood sugar curve decreased by almost 20% when compared with the control group. The inflammatory factor (IL-1β, IL-6) in vivo and cell growth in vitro were almost the same between NU-1000 treatment and normal control groups. This study indicates NU-1000 is a promising vehicle for targeted peptide-based bioactive delivery to the small intestine.

Effect of carboxymethyl konjac glucomannan coating on the stability and colon-targeted delivery performance of fucoxanthin-loaded gliadin nanoparticles

Fucoxanthin (FUC) is a hydrophobic carotenoid that has a protective effect on the colon. To exert the beneficial effects of FUC in the colon and expand its application in functional food, FUC was encapsulated in carboxymethyl konjac glucomannan (CMKGM)-coated gliadin nanoparticles (Gli-CMKGM NPs) in this paper. Gli-CMKGM NPs were prepared at pH 5.0 with Gli/CMKGM mass ratio of 1:1. The formation of Gli-CMKGM NPs was associated with hydrogen bonding, hydrophobic interactions and electrostatic attractions. Additionally, Gli-CMKGM NPs exhibited good stability to pH, salt, heating and storage. The results showed that FUC had been successfully encapsulated in Gli-CMKGM NPs, and the encapsulation efficiency of FUC-Gli-CMKGM NPs was significantly higher than that of uncoated FUC-Gli NPs. FUC-Gli-CMKGM NPs had a nano-spherical structure, and embedded FUC in Gli-CMKGM NPs improved their stabilities to photodegradation and thermal degradation. Furthermore, in vitro release and in vivo organ distribution studies showed that FUC-Gli-CMKGM NPs had an excellent colon targeting function. Overall, our findings illustrated the promise of CMKGM-coated Gli NPs for constructing targeted delivery systems for FUC.

pH/ROS Dual-Sensitive Natural Polysaccharide Nanoparticles Enhance "One Stone Four Birds" Effect of Rhein on Ulcerative Colitis

Rhein (RH), a natural anthraquinone compound, is considered an effective treatment candidate for ulcerative colitis (UC), whose multiple biological activities contribute to UC, including anti-inflammation, antioxidation, intestinal barrier repair, and microflora regulation. However, the application of RH is severely limited by its low water solubility, low bioavailability, and poor colonic targeting. Although some nanoparticles have been developed for the oral delivery of RH, most of them mainly highlighted only one effect of some drug delivery strategies but the above multiple biological activities. Therefore, a multiple polysaccharide-based nanodelivery system, comprising chitosan (CS) and fucoidan (FU), with pH/reactive oxygen species (ROS) sensitivity and mucosal adhesion, was developed and first used to load RH as a comprehensive treatment for UC. Briefly, RH-F/C-NPs were prepared using the polyelectrolyte self-assembly method; the average size of RH-F/C-NPs was 233.1 ± 5.7 nm, and the encapsulation rate of RH was 93.67 ± 1.60%. And it could maintain gastric stability and release RH in the colon with the designed pH/ROS sensitivity contributed by the polysaccharide-based structures. Cellular uptake experiments showed that both NCM 460 cells and RAW 264.7 cells had a good uptake of RH-F/C-NPs. Importantly, the effects of RH were highlighted in in vivo experiments, the results of which showed that RH-F/C-NPs could significantly reduce DSS-induced inflammation by inhibiting the TLR4/NF-κB-mediated anti-inflammatory pathway, the Nrf2/HO-1-mediated antioxidant pathway, colonic mucosal barrier repair, and intestinal microflora regulation. In addition, pharmacokinetic studies have shown that F/C-NPs contribute to the increase in the plasma concentration and the accumulation of RH in the colon to some extent. In short, this study is the first to develop an oral multiple polysaccharide-based nanosystem with pH/ROS dual sensitivity to study the "one stone four birds" therapeutic effect of RH on UC.

Oral Nanomedicines for siRNA Delivery to Treat Inflammatory Bowel Disease

RNA interference (RNAi) therapies have significant potential for the treatment of inflammatory bowel diseases (IBD). Although administering small interfering RNA (siRNA) via an oral route is desirable, various hurdles including physicochemical, mucus, and cellular uptake barriers of the gastrointestinal tract (GIT) impede both the delivery of siRNA to the target site and the action of siRNA drugs at the target site. In this review, we first discuss various physicochemical and biological barriers in the GI tract. Furthermore, we present recent strategies and the progress of oral siRNA delivery strategies to treat IBD. Finally, we consider the challenges faced in the use of these strategies and future directions of oral siRNA delivery strategies.

Sanguinarine ameliorates DSS induced ulcerative colitis by inhibiting NLRP3 inflammasome activation and modulating intestinal microbiota in C57BL/6 mice

BACKGROUND

Sanguinarine (SAN) is an important natural anti-inflammatory constitutes and dietary supplementation with SAN could improve the relative length of the intestine, alter gut microbiota, and enhance growth performance of pigs, broiler chickens, and cattle. However, it is unclear whether it has the therapeutic effect on ulcerative colitis (UC).

PURPOSE

This study aimed to investigate the therapeutic effect of SAN on UC and explore its mechanisms of action.

STUDY DESIGN AND METHODS

Several efficacy indexes of SAN on dextran sulfate sodium (DSS)-induced C57BL/6 mice were evaluated. ELISA kit and western blot analysis were used to evaluate it's anti-inflammatory effect and the mechanism of action. 16S rDNA sequencing detection was used to determine the impact of SAN on gut microbiota.

RESULTS

SAN and Sulfasalazine could significantly improve the colon length, the weight loss, the symptoms and the pathological injury of colon in DSS-induced mice. Meanwhile, SAN could decrease the levels of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, IL-6, IL-13 and IL-18) and increase the levels of anti-inflammatory cytokines (IL-4 and IL-10) in colon, and suppress DSS-induced high expressions of NLRP3, caspase-1 and IL-1β. In addition, SAN (0.5, 1 μM) could inhibit the expression level of NLRP3 and the activation of caspase-1 and IL-1β in lipopolysaccharide-stimulated THP-1 cells in non-cytotoxic doses, which was similar to that of MCC950, a specific inhibitor of NLRP3 inflammasome activation. The abundance changes of many genera such as Muribaculaceae_unclassified, Escherichia-Shigella, Lachnospiraceae_NK4A136_group and Helicobacter were also closely related to the improvement of SAN on intestinal inflammatory response.

CONCLUSION

SAN exhibited therapeutic effect on DSS-induced colitis by blocking NLRP3-(Caspase-1)/IL-1β pathway and improving intestinal microbial dysbiosis. SAN might be developed to treat UC and other disorders associated with microbial dysbiosis.

Herb Polysaccharide-Based Drug Delivery System: Fabrication, Properties, and Applications for Immunotherapy

Herb polysaccharides (HPS) have been studied extensively for their healthcare applications. Though the toxicity was not fully clarified, HPS were widely accepted for their biodegradability and biocompatibility. In addition, as carbohydrate polymers with a unique chemical composition, molecular weight, and functional group profile, HPS can be conjugated, cross-linked, and functionally modified. Thus, they are great candidates for the fabrication of drug delivery systems (DDS). HPS-based DDS (HPS-DDS) can bypass phagocytosis by the reticuloendothelial system, prevent the degradation of biomolecules, and increase the bioavailability of small molecules, thus exerting therapeutic effects. In this review, we focus on the application of HPS as components of immunoregulatory DDS. We summarize the principles governing the fabrication of HPS-DDS, including nanoparticles, micelles, liposomes, microemulsions, hydrogels, and microneedles. In addition, we discuss the role of HPS in DDS for immunotherapy. This comprehensive review provides valuable insights that could guide the design of effective HPS-DDS.

Phragmites rhizoma polysaccharide-based nanocarriers for synergistic treatment of ulcerative colitis

The purpose of this study was to construct Phragmites rhizoma polysaccharide-based nano-drug delivery systems (PRP2-SeNPs-H/Aza-Lips) for synergistically alleviating ulcerative colitis and to investigate the important roles of Phragmites rhizoma polysaccharide-based nanocarriers in PRP2-SeNPs-H/Aza-Lips. Phragmites rhizoma polysaccharide (PRP2) was isolated and used for the preparation of Phragmites rhizoma polysaccharide selenium nanoparticles with low selenium content (PRP2-SeNPs-L) and high selenium content (PRP2-SeNPs-H). Based on the electrostatic attraction between PRP2-SeNPs-H and azathioprine liposomes (Aza-Lips), PRP2-SeNPs-H/Aza-Lips were constructed for precise delivery of the model drug azathioprine (Aza) to colon lesions. Results showed that PRP2 significantly alleviated the clinical symptoms and colon tissue damage and down-regulated the levels of inflammatory factors in serum and colon, demonstrating beneficial effects on mice with ulcerative colitis. PRP2-SeNPs-L had better relieving effects on ulcerative colitis. Phragmites rhizoma polysaccharide-based nanocarriers may protect azathioprine liposomes against gastrointestinal digestion, enhance the therapeutic effects on ulcerative colitis, and significantly reduce liver damage from azathioprine, which helps to improve the efficacy and toxicity of clinical drugs.