Nanoparticle-Based Oral Drug Delivery Systems Targeting the Colon for Treatment of Ulcerative Colitis

Advances in preparation and engineering of plant-derived extracellular vesicles for nutrition intervention

Plant-derived extracellular vesicles (PLEVs), as a type of naturally occurring lipid bilayer membrane structure, represent an emerging delivery vehicle with immense potential due to their ability to encapsulate hydrophobic and hydrophilic compounds, shield them from external environmental stresses, control release, exhibit biocompatibility, and demonstrate biodegradability. This comprehensive review analyzes engineering preparation strategies for natural vesicles, focusing on PLEVs and their purification and surface engineering. Furthermore, it encompasses the latest advancements in utilizing PLEVs to transport active components, serving as a nanotherapeutic system. The prospects and potential development of PLEVs are also discussed. It is anticipated that this work will not only address existing knowledge gaps concerning PLEVs but also provide valuable guidance for researchers in the fields of food science and biomedical studies, stimulating novel breakthroughs in plant-based therapeutic options.

Application of chitosan as nano carrier in the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), is characterized by persistent and recurrent gastrointestinal inflammation. Conventional IBD therapies often involve the use of antibiotics, NSAIDs, biological agents, and immunomodulators. While these medications can mitigate acute inflammatory symptoms, their long-term efficacy is frequently compromised due to cumulative toxic effects. In recent years, significant attention has shifted toward nanoparticle (NP)-based therapies as potential alternatives for IBD management. Various drug delivery strategies, including those targeting microbiota interactions, ligand-receptor binding, pH sensitivity, biodegradability, pressure response, and specific charge and size parameters, have been explored and optimized in animal studies. This review provides a comprehensive overview of the current landscape of chitosan NP-mediated drug delivery systems for IBD treatment. Additionally, it will discuss the prevailing challenges and propose future research directions to advance chitosan NP-based therapeutic strategies for IBD.

Oral colon-targeted pH-responsive polymeric nanoparticles loading naringin for enhanced ulcerative colitis therapy

An oral colon-targeted drug delivery system holds great potential in preventing systemic toxicity and preserving the therapeutic benefits of ulcerative colitis (UC) treatment. In this study, we developed a negatively charged PLGA-PEG nanoparticle system for encapsulating naringin (Nar). Additionally, chitosan and mannose were coated on the surface of these nanoparticles to enhance their mucosal adsorption and macrophage targeting abilities. The resulting nanoparticles, termed MC@Nar-NPs, exhibited excellent resistance against decomposition in the strong acidic gastrointestinal environment and specifically accumulated at inflammatory sites. Upon payload release, MC@Nar-NPs demonstrated remarkable efficacy in alleviating colon inflammation as evidenced by reduced levels of pro-inflammatory cytokines in both blood and colon tissues, as well as the scavenging of reactive oxygen species (ROS) in the colon. This oral nanoparticle delivery system represents a novel approach to treating UC by utilizing Chinese herbal ingredient-based oral delivery and provides a theoretical foundation for local and precise intervention in specific UC treatment.

Oral delivery of stabilized lipid nanoparticles for nucleic acid therapeutics

Gastrointestinal disorders originate in the gastrointestinal tract (GIT), and the therapies can benefit from direct access to the GIT achievable through the oral route. RNA molecules show great promise therapeutically but are highly susceptible to degradation and often require a carrier for cytoplasmic access. Lipid nanoparticles (LNPs) are clinically proven drug-delivery agents, primarily administered parenterally. An ideal Orally Delivered (OrD) LNP formulation should overcome the diverse GI environment, successfully delivering the drug to the site of action. A versatile OrD LNP formulation has been developed to encapsulate and deliver siRNA and mRNA in this paper. The formulations were prepared by the systematic addition of cationic lipid to the base LNP formulation, keeping the total of cationic lipid and ionizable lipid to 50 mol%. Biorelevant media stability depicted increased resistance to bile salt mediated destabilization upon the addition of the cationic lipid, however the in vitro efficacy data underscored the importance of the ionizable lipid. Based on this, OrD LNP was selected comprising of 20% cationic lipid and 30% ionizable lipid. Further investigation revealed the enhanced efficacy of OrD LNP in vitro after incubation in different dilutions of fasted gastric, fasted intestinal media, and mucin. Confocal imaging and flow cytometry confirmed uptake while in vivo studies demonstrated efficacy with siRNA and mRNA as payloads. Taken together, this research introduces OrD LNP to deliver nucleic acid locally to the GIT.

The miRNA Landscape in Crohn's disease: Implications for novel therapeutic approaches and interactions with Existing therapies

MicroRNAs (miRNAs), which are non-coding RNAs consisting of 18-24 nucleotides, play a crucial role in the regulatory pathways of inflammatory diseases. Several recent investigations have examined the potential role of miRNAs in forming Crohn's disease (CD). It has been suggested that miRNAs serve as diagnostics for both fibrosis and inflammation in CD due to their involvement in the mechanisms of CD aggravation and fibrogenesis. More information on CD pathophysiology could be obtained by identifying the miRNAs concerned with CD and their target genes. These findings have prompted several in vitro and in vivo investigations into the putative function of miRNAs in CD treatment. Although there are still many unanswered questions, the growing body of evidence has brought miRNA-based therapy one step closer to clinical practice. This extensive narrative study offers a concise summary of the most current advancements in CD. We go over what is known about the diagnostic and therapeutic benefits of miRNA mimicry and inhibition so far, and we see what additional miRNA family targets could be useful for treating CD-related inflammation and fibrosis.

Natural medicines-derived carbon dots as novel oral antioxidant administration strategy for ulcerative colitis therapy

BACKGROUND

Ulcerative colitis (UC) is a chronic intestinal inflammation, resulting in a global healthcare challenge with no real specific medicine. Natural medicines are recognized as a potential clinical alternative therapy, but their applications are limited by poor solubility and low bioavailability.

RESULTS

In this work, inspired by the natural medicines of ancient China, novel functional carbon dots derived from Magnetite and Medicated Leaven (MML-CDs) were synthesized by hydrothermal method, and confirmed their ultrasmall nano-size (3.2 ± 0.6 nm) and Fe doped surface structure, thereby with excellent gastrointestinal stability, remarkable capabilities in eliminating ROS, and highly biocompatibility. With no external stimuli, the oral administration of MML-CDs demonstrated obvious alleviation to UC. Further experiments pointed that MML-CDs could improve hemostasis capability, suppress inflammation reactions and oxidative stress, and up-regulate the expression of tight junction proteins. Furthermore, MML-CDs also showed well regulation in the dysbiosis of intestinal flora.

CONCLUSION

Overall, above evidence reveals that green-synthesized MML-CDs can significantly alleviate intestinal bleeding, inhibit colon inflammation, and repair colonic barrier damage, further regulating intestinal flora and intestinal inflammation microenvironment. Our findings provide an efficient oral administration of MML-CDs as a novel therapy strategy for ulcerative colitis.

Applications of polysaccharides in enzyme-triggered oral colon-specific drug delivery systems: A review

Enzyme-triggered oral colon-specific drug delivery system (EtOCDDS1) can withstand the harsh stomach and small intestine environments, releasing encapsulated drugs selectively in the colon in response to colonic microflora, exerting local or systematic therapeutic effects. EtOCDDS boasts high colon targetability, enhanced drug bioavailability, and reduced systemic side effects. Polysaccharides are extensively used in enzyme-triggered oral colon-specific drug delivery systems, and its colon targetability has been widely confirmed, as their properties meet the demand of EtOCDDS. Polysaccharides, known for their high safety and excellent biocompatibility, feature modifiable structures. Some remain undigested in the stomach and small intestine, whether in their natural state or after modifications, and are exclusively broken down by colon-resident microbiota. Such characteristics make them ideal materials for EtOCDDS. This article reviews the design principles of EtOCDDS as well as commonly used polysaccharides and their characteristics, modifications, applications and specific mechanism for colon targeting. The article concludes by summarizing the limitations and potential of ETOCDDS to stimulate the development of innovative design approaches.

Exploring the Therapeutic Potential of Green-Synthesized Gold Nanoparticles and Ericaria selaginoides Extract for Inflammatory Bowel Disease

Addressing disease remission and treatment adherence in inflammatory bowel diseases (IBDs), such as Crohn's disease, poses significant challenges due to underlying oxidative and inflammatory processes. Nanotechnology emerges as a promising avenue for enhancing therapeutic outcomes in IBD by optimizing drug bioactivity, reducing toxicity, and extending circulation time. Gold nanoparticles, known for their resistance to gastrointestinal pH and possessing antioxidant and anti-inflammatory properties, offer particular promise. They can be produced by green synthesis with seaweed Ericaria selaginoides (ES), itself associated with gastroprotective and anti-inflammatory activities. In a murine model of Crohn's disease induced with 8% acetic acid, pretreatment with dexamethasone (0.2 mL/30 g) or Au@ES (25 and 50 mg/kg) effectively mitigated inflammatory features. Notably, ES (50 mg/kg) and Au@ES (50 mg/kg) administration resulted in significant reductions in both macroscopic and microscopic inflammation scores compared to the disease control group. Furthermore, these treatments normalized inflammatory cytokine expression while safeguarding myenteric plexus glial cells. They also impeded neutrophil activation, leading to reduced myeloperoxidase activity and lipid peroxidation, coupled with increased glutathione levels. In conclusion, ES and Au@ES exhibit potent efficacy in counteracting inflammation and oxidation processes in an experimental Crohn's disease model, suggesting their potential as alternative therapeutic strategies for IBD.

An overview on recent approaches for colonic drug delivery systems

Colon-targeted drug delivery systems have garnered significant interest as potential solutions for delivering various medications susceptible to acidic and catalytic degradation in the gastrointestinal (GI) tract or as a means of treating colonic diseases naturally with fewer overall side effects. The increasing demand for patient-friendly drug administration underscores the importance of colonic drug delivery, particularly through noninvasive methods like nanoparticulate drug delivery technologies. Such systems offer improved patient compliance, cost reduction, and therapeutic advantages. This study places particular emphasis on formulations and discusses recent advancements in various methods for designing colon-targeted drug delivery systems and their medicinal applications.

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.

Review on novel targeted enzyme drug delivery systems: enzymosomes

The goal of this review is to present enzymosomes as an innovative means for site-specific drug delivery. Enzymosomes make use of an enzyme's special characteristics, such as its capacity to accelerate the reaction rate and bind to a particular substrate at a regulated rate. Enzymosomes are created when an enzyme forms a covalent linkage with a liposome or lipid vesicle surface. To construct enzymosomes with specialized activities, enzymes are linked using acylation, direct conjugation, physical adsorption, and encapsulation techniques. By reducing the negative side effects of earlier treatment techniques and exhibiting efficient medication release, these cutting-edge drug delivery systems improve long-term sickness treatments. They could be a good substitute for antiplatelet medication, gout treatment, and other traditional medicines. Recently developed supramolecular vesicular delivery systems called enzymosomes have the potential to improve drug targeting, physicochemical characteristics, and ultimately bioavailability in the pharmaceutical industry. Enzymosomes have advantages over narrow-therapeutic index pharmaceuticals as focusing on their site of action enhances both their pharmacodynamic and pharmacokinetic profiles. Additionally, it reduces changes in normal enzymatic activity, which enhances the half-life of an enzyme and accomplishes enzyme activity on specific locations.

Highly Effective Nobiletin-MPN in Yeast Microcapsules for Targeted Modulation of Oxidative Stress, NLRP3 Inflammasome Activation, and Immune Responses in Ulcerative Colitis

Inflammatory bowel disease (IBD) etiology is intricately linked to oxidative stress and inflammasome activation. Natural antioxidant nobiletin (NOB) contains excellent anti-inflammatory properties in alleviating intestinal injury. However, the insufficient water solubility and low bioavailability restrict its oral intervention for IBD. Herein, we constructed a highly efficient NOB-loaded yeast microcapsule (YM, NEFY) exhibiting marked therapeutic efficacy for dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) at a low oral dose of NOB (20 mg/kg). We utilized the metal polyphenol network (MPN) formed by self-assembly of epigallocatechin gallate (EGCG) and FeCl3 as the intermediate carrier to improve the encapsulation efficiency (EE) of NOB by 4.2 times. These microcapsules effectively alleviated the inflammatory reaction and oxidative stress of RAW264.7 macrophages induced by lipopolysaccharide (LPS). In vivo, NEFY with biocompatibility enabled the intestinal enrichment of NOB through controlled gastrointestinal release and macrophage targeting. In addition, NEFY could inhibit NLRP3 inflammasome and balance the macrophage polarization, which favors the complete intestinal mucosal barrier and recovery of colitis. Based on the oral targeted delivery platform of YM, this work proposes a novel strategy for developing and utilizing the natural flavone NOB to intervene in intestinal inflammation-related diseases.

Taking SCFAs produced by Lactobacillus reuteri orally reshapes gut microbiota and elicits antitumor responses

BACKGROUND

Colorectal cancer (CRC) incidence is increasing in recent years due to intestinal flora imbalance, making oral probiotics a hotspot for research. However, numerous studies related to intestinal flora regulation ignore its internal mechanisms without in-depth research.

RESULTS

Here, we developed a probiotic microgel delivery system (L.r@(SA-CS)2) through the layer-by-layer encapsulation technology of alginate (SA) and chitosan (CS) to improve gut microbiota dysbiosis and enhance anti-tumor therapeutic effect. Short chain fatty acids (SCFAs) produced by L.r have direct anti-tumor effects. Additionally, it reduces harmful bacteria such as Proteobacteria and Fusobacteriota, and through bacteria mutualophy increases beneficial bacteria such as Bacteroidota and Firmicutes which produce butyric acid. By binding to the G protein-coupled receptor 109A (GPR109A) on the surface of colonic epithelial cells, butyric acid can induce apoptosis in abnormal cells. Due to the low expression of GPR109A in colon cancer cells, MK-6892 (MK) can be used to stimulate GPR109A. With increased production of butyrate, activated GPR109A is able to bind more butyrate, which further promotes apoptosis of cancer cells and triggers an antitumor response.

CONCLUSION

It appears that the oral administration of L.r@(SA-CS)2 microgels may provide a treatment option for CRC by modifying the gut microbiota.

Oral delivery of probiotics using single-cell encapsulation

Adequate intake of live probiotics is beneficial to human health and wellbeing because they can help treat or prevent a variety of health conditions. However, the viability of probiotics is reduced by the harsh environments they experience during passage through the human gastrointestinal tract (GIT). Consequently, the oral delivery of viable probiotics is a significant challenge. Probiotic encapsulation provides a potential solution to this problem. However, the production methods used to create conventional encapsulation technologies often damage probiotics. Moreover, the delivery systems produced often do not have the required physicochemical attributes or robustness for food applications. Single-cell encapsulation is based on forming a protective coating around a single probiotic cell. These coatings may be biofilms or biopolymer layers designed to protect the probiotic from the harsh gastrointestinal environment, enhance their colonization, and introduce additional beneficial functions. This article reviews the factors affecting the oral delivery of probiotics, analyses the shortcomings of existing encapsulation technologies, and highlights the potential advantages of single-cell encapsulation. It also reviews the various approaches available for single-cell encapsulation of probiotics, including their implementation and the characteristics of the delivery systems they produce. In addition, the mechanisms by which single-cell encapsulation can improve the oral bioavailability and health benefits of probiotics are described. Moreover, the benefits, limitations, and safety issues of probiotic single-cell encapsulation technology for applications in food and beverages are analyzed. Finally, future directions and potential challenges to the widespread adoption of single-cell encapsulation of probiotics are highlighted.

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.

pH-responsive CuS/DSF/EL/PVP nanoplatform alleviates inflammatory bowel disease in mice via regulating gut immunity and microbiota

The clinical treatment of inflammatory bowel disease (IBD) is challenging. We developed copper sulfate (CuS)/disulfiram (DSF)/methacrylic acid-ethyl acrylate copolymer (EL)/polyvinylpyrrolidone (PVP) nanoplatform (CuS/DSF/EL/PVP) and evaluated its efficiency for treating IBD. After oral administration, the pH-sensitive EL protected the CuS/DSF/EL/PVP against degradation by acidic gastric juices. Once the colon was reached, EL was dissolved, releasing DSF and Cu2+. Further, the main in vivo metabolite of DSF can bind to Cu2+ and form copper (II) N, N-diethyldithiocarbamate (CuET), which significantly alleviated acute colitis in mice. Notably, CuS/DSF/EL/PVP outperformed CuS/EL/PVP and DSF/EL/PVP nanoplatforms in reducing colonic pathology and improving the secretion of inflammation-related cytokines (such as IL-4 and IL-10) in the colonic mucosa. RNA-seq analysis revealed that the nanoplatform reduced colonic inflammation and promoted intestinal mucosal repair by upregulating C-type lectin receptor (CLR)-related genes and signaling pathways. Furthermore, CuS/DSF/EL/PVP showed potential for improving colitis Th1/Th17 cells through innate immunity stimulation, down-regulation of inflammatory cytokines, and upregulation of anti-inflammatory cytokines. Additionally, the intervention with CuS/DSF/EL/PVP led to increased intestinal flora diversity, decreased Escherichia-Shigella abundance, and elevated levels of short-chain fatty acid (SCFA)-producing bacteria Prevotella, Lactobacillus, and Bifidobacterium, indicating their potential to modulate the dysregulated intestinal flora and suppress inflammation. STATEMENT OF SIGNIFICANCE: Our study introduces the CuS/DSF/EL/PVP nanoplatform as a therapeutic strategy for treating inflammatory bowel disease (IBD). This approach demonstrates significant efficacy in targeting the colon and alleviating acute colitis in mice. It uniquely modulates gut immunity and microbiota, exhibiting a notable impact on inflammation-related cytokines and promoting intestinal mucosal repair. The nanoplatform's ability to regulate gut flora diversity, combined with its cost-effective and scalable production, positions it as a potentially transformative treatment for IBD, offering new avenues for personalized medical interventions.

Resistant starch and the gut microbiome: Exploring beneficial interactions and dietary impacts

The intricate relationship between resistant starch (RS) and the gut microbiome presents a dynamic frontier in nutrition science. This review synthesizes current understandings of how RS, an indigestible form of starch found naturally in certain foods and also enhanced through various modification methods, interacts with the gut microbiome. We particularly focus on how RS fermentation in the colon contributes to the production of beneficial volatile fatty acids (VFAs) such as butyrate, acetate, and propionate. These VFAs have been recognized for their vital roles in maintaining gut barrier integrity, modulating inflammation, and potentially influencing systemic health. Additionally, we discuss the dietary implications of consuming foods rich in RS, both in terms of gut health and broader metabolic outcomes. By consolidating these insights, we emphasize the significance of RS in the context of dietary strategies aimed at harnessing the gut microbiome's potential to impact human health.

Herbal Theranostics: Controlled, Targeted Delivery and Imaging of Herbal Molecules

Modern medicine relies on a small number of key biologics, which can be found in nature but require further characterization and purification before they can be used. Since the herbal remedy is given through a dated and ineffective method of drug administration, its effectiveness is diminished. The novel form of medicine delivery has the potential to increase the effectiveness of herbal substances while decreasing their side effects. This is the main idea behind utilising different ways of drug delivery in herbal treatments. Several benefits arise from novel formulations of herbal compounds as compared to their conventional counterparts. These include enhanced penetrating ability into tissues, constant delivery of effective doses, and resistance to physical and chemical degradation. Controlled and targeted delivery that include herbal components allow for more traditional dosing while simultaneously increasing their efficacy. Enhancing the biodistribution and target site accumulation of systemically administered herbal medicines is the goal of nanomedicine formulations. The field of nanotheranostics has made significant advancements in the development of herbal compounds by combining diagnostic and therapeutic functions on a single nanoscale platform. It is critically important to create a theranostic nanoplatform that is derived from plants and is intrinsically "all-in-one" for single molecules. In addition to examining the mechanistic approach to nanoparticle synthesis, this review highlights the therapeutic effects of nanoscale phytochemical delivery systems. Furthermore, we have evaluated the scope for future advancements in this field, discussed several nanoparticles that have been developed recently for herbal imaging, and provided experimental evidence that supports their usage.

Fexofenadine-loaded chitosan coated solid lipid nanoparticles (SLNs): A potential oral therapy for ulcerative colitis

The targeting and mucoadhesive features of chitosan (CS)-linked solid lipid nanoparticles (SLNs) were exploited to efficiently deliver fexofenadine (FEX) into the colon, forming a novel and potential oral therapeutic option for ulcerative colitis (UC) treatment. Different FEX-CS-SLNs with varied molecular weights of CS were prepared and optimized. Optimized FEX-CS-SLNs exhibited 229 ± 6.08 nm nanometric size, 36.3 ± 3.18 mV zeta potential, 64.9 % EE, and a controlled release profile. FTIR, DSC, and TEM confirmed good drug entrapment and spherical particles. Mucoadhesive properties of FEX-CS-SLNs were investigated through mucin incubation and exhibited considerable mucoadhesion. The protective effect of FEX-pure, FEX-market, and FEX-CS-SLNs against acetic acid-induced ulcerative colitis in rats was examined. Oral administration of FEX-CS-SLNs for 14 days before ulcerative colitis induction reversed UC symptoms and almost restored the intestinal mucosa to normal integrity and inhibited Phosphatidylinositol-3 kinase (73.6 %), protein kinase B (73.28 %), and elevated nuclear factor erythroid 2-related factor 2 (185.9 %) in colonic tissue. Additionally, FEX-CS-SLNs inhibited tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) to (70.79 % & 72.99 %) in colonic tissue. The ameliorative potential of FEX-CS-SLNs outperformed that of FEX-pure and FEX-market. The exceptional protective effect of FEX-CS-SLNs makes it a potentially effective oral system for managing ulcerative colitis.

Solanum lycopersicum (Tomato)-Derived Nanovesicles Accelerate Wound Healing by Eliciting the Migration of Keratinocytes and Fibroblasts

Plant-derived nanovesicles have been considered interesting in medicine for their breakthrough biological effects, including those relevant to wound healing. However, tomato-derived nanovesicles (TDNVs) have not been studied for their effects on wound closure yet. TDNVs were isolated from Solanum lycopersicum (var. Piccadilly) ripe tomatoes by ultracentrifugation. Extract (collected during the isolation procedure) and NVs (pellet) were characterized by transmission electron microscopy and laser Doppler electrophoresis. Wound healing in the presence of Extract or NVs was analyzed by a scratch assay with monocultures of human keratinocytes (HUKE) or NIH-3T3 mouse fibroblasts. Cell proliferation and migration were studied by MTT and agarose spot assay, respectively. The vesicles in the Extract and NV samples were nanosized with a similar mean diameter of 115 nm and 130 nm, respectively. Both Extract and NVs had already accelerated wound closure of injured HUKE and NIH-3T3 monocultures by 6 h post-injury. Although neither sample exerted a cytotoxic effect on HUKE and NIH-3T3 fibroblasts, they did not augment cell proliferation. NVs and the Extract increased cell migration of both cell types. NVs from tomatoes may accelerate wound healing by increasing keratinocyte and fibroblast migration. These results indicate the potential therapeutic usefulness of TDNVs in the treatment of chronic or hard-to-heal ulcers.

Recent Insight into Herbal Bioactives-based Novel Approaches for Chronic Intestinal Inflammatory Disorders Therapy

Inflammatory bowel disease (IBD) is a life-threatening complex disease. It causes chronic intestinal inflammation in GIT. IBD significantly affects people's lifestyles and carries a high risk of colon cancer. IBD involves the rectum, ileum, and colon, with clinical manifestations of bloody stools, weight loss, diarrhea, and abdominal pain. The prevalence of inflammatory disease is increasing dramatically worldwide. Over 16 million people are affected annually in India, with an economic burden of $6.8- $8.8 billion for treatment. Modern medicine can manage IBD as immunosuppressive agents, corticosteroids, tumor necrosis factor antagonists, integrin blockers, and amino-salicylates. However, these approaches are allied with limitations such as limited efficacy, drug resistance, undesired side effects, and overall cost, which cannot be ignored. Hence, the herbal bioactives derived from various plant resources can be employed in managing IBD. Science Direct, PubMed, Google, and Scopus databases have been searched for conclusively relevant herbal plant-based anti-inflammatory agent compositions. Studies were screened through analysis of previously published review articles. Eminent herbal bioactives, namely curcumin, resveratrol, ellagic acid, silybin, catechin, kaempferol, icariin, glycyrrhizin acid, berberine, quercetin, rutin, and thymol are reported to be effective against IBD. Herbal leads are promising treatment options for IBD; they have been shown to display antiinflammatory and antioxidant properties by targeting enzymes and regulating the expressions of various inflammatory mediators. Natural products have been reported to have anti-inflammatory properties in various clinical and preclinical studies, and some are available as herbal preparations. Herbal medicine would be promising in association with the implication of a novel drug delivery system for managing IBD.

Oral delivery of pH-sensitive nanoparticles loaded Celastrol targeting the inflammatory colons to treat ulcerative colitis

The incidence of ulcerative colitis (UC) is rapidly rising worldwide. Oral drug delivery system is a promising approach for treating UC, but it often fails to accumulate to the inflammatory lesions, thus, it is impressive to develop a colon-targeted oral delivery system for preventing systemic toxicity and maintaining UC therapeutics. Here, a negative-charged PLGA nanoparticle system was designed to encapsulate celastrol (Cel), and then chitosan and mannose were coated on the surface of the nanoparticles (MC@Cel-NPs) to endow these nanoparticles with the mucosal adsorption and macrophage targeting abilities. MC@Cel-NPs demonstrate excellent resist decomposition ability against the strong acidic gastrointestinal environment, and accumulates in the specific inflammatory sites through the affinity of electrostatic reaction. After releasing the payload, MC@Cel-NPs could remarkably alleviate the colon inflammation, which was evidenced by the decrease in pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 in both blood and colon sections, and scavenging reactive oxygen species (ROS) in colon cells, including macrophage, neutrophil, T cell, and B cell. This nanoparticle system provided a new approach for treating UC through a Chinese herbal ingredient-related oral delivery manner.

Dual-Targeted Nanoparticle-in-Microparticle System for Ulcerative Colitis Therapy

Conventional oral therapy for ulcerative colitis (UC) is associated with premature release or degradation of drugs in the harsh gastrointestinal environment, resulting in reduced therapeutic effectiveness. Consequently, the present study aims to develop a dual-targeted delivery system with a nanoparticle-in-microparticle (nano-in-micro) structure. The prepared Asiatic Acid-loaded delivery system (AA/CDM-BT-ALG) has pH-sensitive properties. Cellular uptake evaluation confirms that nanoparticles exhibit targeted absorption by macrophages and Caco-2 cells through mannose (Man) receptor and biotin-mediated endocytosis, respectively. Therefore, this mechanism effectively enhances intracellular drug concentration. Additionally, the biodistribution study conducted on the gastrointestinal tract of mice indicates that the colon of the microspheres group shows higher fluorescence intensity with longer duration than the other groups. This finding indicates that the microspheres exhibit selective accumulation in areas of colon inflammation. In vivo experiments in colitis mice showed that AA/CDM-BT-ALG significantly alleviates the histopathological characteristics of the colon, reduced neutrophil, and macrophage infiltration, and decreases pro-inflammatory cytokine expression. Furthermore, the effect of AA/CDM-BT-ALG on colitis is validated to be closely related to the TLR4/MyD88/NF-κB signaling pathway. The present findings suggest that the development of a dual-targeted delivery system is accomplished effectively, with the potential to serve as a drug-controlled release system for treating UC.

Acid-base transformative HADLA micelles alleviate colitis by restoring adaptive immunity and gut microbiome

Inflammatory bowel disease (IBD) is a worldwide public health issue with an increasing number of patients annually. However, there is no curative drug for IBD, and the present medication for IBD generally focuses on suppressing hyperactive immune responses, which can only delay disease progression but inevitably induce off-target side effects, including infections and cancers. Herein, late-model orally administered nanotherapeutic micelles (HADLA) were developed based on a conjugate of hyaluronic acid (HA) and dehydrolithocholic acid (DLA), which was simple to achieve and obtained satisfactory therapeutic efficacy in a murine colitis model with a full safety profile. HADLA is capable of targeting inflammatory colon tissues, restoring intestinal barrier function and reducing intestinal epithelial cell death. Moreover, it modulates the adaptive immune system by inhibiting the activation of pathogenic T helper 17 (Th17) cells, and it exhibits more remarkable effects in preventing colitis than DLA alone. Finally, HADLA exhibits a remarkable ability to modulate dysregulated gut microbiomes by increasing beneficial probiotics and decreasing pathogenic bacteria, such as Turicibacter. Compared with the current systemic or subcutaneous administration of biologics, this study opens new avenues in the oral delivery of immune-modulating nanomedicine and introduces DLA as a new medication for IBD treatment.

Emerging drug delivery systems with traditional routes - A roadmap to chronic inflammatory diseases

Inflammation is prevalent and inevitable in daily life but can generally be accommodated by the immune systems. However, incapable self-healing and persistent inflammation can progress to chronic inflammation, leading to prevalent or fatal chronic diseases. This review comprehensively covers the topic of emerging drug delivery systems (DDSs) for the treatment of chronic inflammatory diseases (CIDs). First, we introduce the basic biology of the chronic inflammatory process and provide an overview of the main CIDs of the major organs. Next, up-to-date information on various DDSs and the associated strategies for ensuring targeted delivery and stimuli-responsiveness applied to CIDs are discussed extensively. The implementation of traditional routes of drug administration to maximize their therapeutic effects against CIDs is then summarized. Finally, perspectives on future DDSs against CIDs are presented.

Delivery Strategies of Probiotics from Nano- and Microparticles: Trends in the Treatment of Inflammatory Bowel Disease-An Overview

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder, most known as ulcerative colitis (UC) and Crohn's disease (CD), that affects the gastrointestinal tract (GIT), causing considerable symptoms to millions of people around the world. Conventional therapeutic strategies have limitations and side effects, prompting the exploration of innovative approaches. Probiotics, known for their potential to restore gut homeostasis, have emerged as promising candidates for IBD management. Probiotics have been shown to minimize disease symptoms, particularly in patients affected by UC, opening important opportunities to better treat this disease. However, they exhibit limitations in terms of stability and targeted delivery. As several studies demonstrate, the encapsulation of the probiotics, as well as the synthetic drug, into micro- and nanoparticles of organic materials offers great potential to solve this problem. They resist the harsh conditions of the upper GIT portions and, thus, protect the probiotic and drug inside, allowing for the delivery of adequate amounts directly into the colon. An overview of UC and CD, the benefits of the use of probiotics, and the potential of micro- and nanoencapsulation technologies to improve IBD treatment are presented. This review sheds light on the remarkable potential of nano- and microparticles loaded with probiotics as a novel and efficient strategy for managing IBD. Nonetheless, further investigations and clinical trials are warranted to validate their long-term safety and efficacy, paving the way for a new era in IBD therapeutics.

Probing milk extracellular vesicles for intestinal delivery of RNA therapies

BACKGROUND

Oral delivery remains unattainable for nucleic acid therapies. Many nanoparticle-based drug delivery systems have been investigated for this, but most suffer from poor gut stability, poor mucus diffusion and/or inefficient epithelial uptake. Extracellular vesicles from bovine milk (mEVs) possess desirable characteristics for oral delivery of nucleic acid therapies since they both survive digestion and traverse the intestinal mucosa.

RESULTS

Using novel tools, we comprehensively examine the intestinal delivery of mEVs, probing whether they could be used as, or inform the design of, nanoparticles for oral nucleic acid therapies. We show that mEVs efficiently translocate across the Caco-2 intestinal model, which is not compromised by treatment with simulated intestinal fluids. For the first time, we also demonstrate transport of mEVs in novel 3D 'apical-out' and monolayer-based human intestinal epithelial organoids (IEOs). Importantly, mEVs loaded with small interfering RNA (siRNA) induced (glyceraldehyde 3-phosphate dehydrogenase, GAPDH) gene silencing in macrophages. Using inflammatory bowel disease (IBD) as an example application, we show that administration of anti-tumour necrosis factor alpha (TNFα) siRNA-loaded mEVs reduced inflammation in a IBD rat model.

CONCLUSIONS

Together, this work demonstrates that mEVs could either act as natural and safe systems for oral delivery or nucleic acid therapies, or inform the design of synthetic systems for such application.

Oral Nanotherapeutics of Andrographolide/Carbon Monoxide Donor for Synergistically Anti-inflammatory and Pro-resolving Treatment of Ulcerative Colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology affecting the colon and rectum. Current therapeutics are focused on suppressing inflammation but are ineffective. Combining anti-inflammatory therapeutic approaches with pro-resolution might be a superior strategy for UC treatment. Andrographolide (AG), an active compound from the plant Andrographis paniculata, presented anti-inflammatory effects in various inflammatory diseases. Gaseous mediators, such as carbon monoxide (CO), have a role in inflammatory resolution. Herein, we developed a dextran-functionalized PLGA nanocarrier for efficient delivery of AG and a carbon monoxide donor (CORM-2) for synergistically anti-inflammatory/pro-resolving treatment of UC (AG/CORM-2@NP-Dex) based on PLGA with good biocompatibility, slow drug release, efficient targeting, and biodegradability. The resulting nanocarrier had a nano-scaled diameter of ∼200 nm and a spherical shape. After being coated with dextran (Dex), the resulting AG/CORM-2@NP-Dex could be efficiently internalized by Colon-26 and Raw 264.7 cells in vitro and preferentially localized to the inflamed colon with chitosan/alginate hydrogel protection by gavage. AG/CORM-2@NP-Dex performed anti-inflammatory effects by eliminating the over-production of pro-inflammatory mediator, nitric oxide (NO), and down-regulating the expression of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), while it showed pro-resolving function by accelerating M1 to M2 macrophage conversion and up-regulating resolution-related genes (IL-10, TGF-β, and HO-1). In the colitis model, oral administration of AG/CORM-2@NP-Dex in a chitosan/alginate hydrogel also showed synergistically anti-inflammatory/pro-resolving effects, therefore relieving UC effectively. Without appreciable systemic toxicity, this bifunctional nanocarrier represents a novel therapeutic approach for UC and is expected to achieve long-term inflammatory remission.

Updated immunomodulatory roles of gut flora and microRNAs in inflammatory bowel diseases

Inflammatory bowel disease is a heterogeneous intestinal inflammatory disorder, including ulcerative colitis (UC) and Crohn's disease (CD). Existing studies have shown that the pathogenesis of IBD is closely related to the host's genetic susceptibility, intestinal flora disturbance and mucosal immune abnormalities, etc. It is generally believed that there are complicated interactions between host immunity and intestinal microflora/microRNAs during the occurrence and progression of IBD. Intestinal flora is mainly composed of bacteria, fungi, viruses and helminths. These commensals are highly implicated in the maintenance of intestinal microenvironment homeostasis alone or in combination. MiRNA is an endogenous non-coding small RNA with a length of 20 to 22 nucleotides, which can perform a variety of biological functions by silencing or activating target genes through complementary pairing bonds. A large quantity of miRNAs are involved in intestinal inflammation, mucosal barrier integrity, autophagy, vesicle transportation and other small RNA alterations in IBD circumstance. In this review, the immunomodulatory roles of gut flora and microRNAs are updated in the occurrence and progression of IBD. Meanwhile, the gut flora and microRNA targeted therapeutic strategies as well as other immunomodulatory approaches including TNF-α monoclonal antibodies are also emphasized in the treatment of IBD.

Advances in natural compound-based nanomedicine and the interaction with gut microbiota in ulcerative colitis therapy

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder of the large intestine. Previous studies have indicated that the gut microbiota plays an important role in the triggers, development, and treatment response of UC. Natural active molecules and their nanoformulations show huge potential for treating UC. The nanoparticles can regulate the gut microbiota and metabolites, whereas gut microbiota-mediated effects on nanomedicines can also bring additional therapeutic benefits. Therefore, this review aims to integrate current research on natural active molecule-based nanomedicines for UC therapy and their interaction with the gut microbiota. Here, this discussion focuses on the effects and functions of gut microbiota and metabolites in UC. The use of active molecules and the nanoformulation from natural compounds for UC therapy have been provided. The interactions between the gut microbiota and nanomedicines are derived from natural products and elucidate the possible biological mechanisms involved. Finally, the challenges and future directions for enhancing the therapeutic efficacy of nanomedicine in treating UC are proposed.

TRP (transient receptor potential) ion channel family: structures, biological functions and therapeutic interventions for diseases

Transient receptor potential (TRP) channels are sensors for a variety of cellular and environmental signals. Mammals express a total of 28 different TRP channel proteins, which can be divided into seven subfamilies based on amino acid sequence homology: TRPA (Ankyrin), TRPC (Canonical), TRPM (Melastatin), TRPML (Mucolipin), TRPN (NO-mechano-potential, NOMP), TRPP (Polycystin), TRPV (Vanilloid). They are a class of ion channels found in numerous tissues and cell types and are permeable to a wide range of cations such as Ca²⁺, Mg²⁺, Na⁺, K⁺, and others. TRP channels are responsible for various sensory responses including heat, cold, pain, stress, vision and taste and can be activated by a number of stimuli. Their predominantly location on the cell surface, their interaction with numerous physiological signaling pathways, and the unique crystal structure of TRP channels make TRPs attractive drug targets and implicate them in the treatment of a wide range of diseases. Here, we review the history of TRP channel discovery, summarize the structures and functions of the TRP ion channel family, and highlight the current understanding of the role of TRP channels in the pathogenesis of human disease. Most importantly, we describe TRP channel-related drug discovery, therapeutic interventions for diseases and the limitations of targeting TRP channels in potential clinical applications.

Ionically bridged dexamethasone sodium phosphate-zinc-PLGA nanocomplex in alginate microgel for the local treatment of ulcerative colitis

Colon-targeted oral drug delivery systems comprising nanoparticles and microparticles have emerged as promising tools for the treatment of ulcerative colitis (UC) because they minimize side effects and maximize the local drug concentration. Dexamethasone sodium phosphate (DSP) is a potent anti-inflammatory glucocorticoid used for the treatment of UC. However, it remains a rather short-term treatment option owing to its side effects. In the present study, we developed the alginate gel encapsulating ionically bridged DSP-zinc-poly(lactic-co-glycolic acid) (PLGA) nanocomplex (DZP-NCs-in-microgel) for the oral local treatment of UC. The successful encapsulation of DSP-zinc-PLGA nanocomplex (DZP-NCs) in alginate microgel was confirmed by SEM imaging. The prepared gel released DZP-NCs in the stimulated intestinal fluid and dampened the release of DSP in the upper gastrointestinal tract. Furthermore, DZP-NCs-in-microgel alleviated colonic inflammation in a mouse model of dextran sodium sulfate-induced colitis by relieving clinical symptoms and histological marks. Our results suggest a novel approach for the oral colon-targeted delivery of dexamethasone sodium phosphate for the treatment of UC.

Recent advances in mucus-penetrating nanomedicines for oral treatment of colonic diseases

INTRODUCTION

Oral administration is the most common route for treating colonic diseases that present increased incidences in recent years. Colonic mucus is a critical rate-limiting barrier for the accumulation of oral therapeutics in the colonic tissues. To overcome this obstacle, mucus-penetrating nanotherapeutics have been exploited to increase the accumulated amounts of drugs in the diseased sites and improve their treatment outcomes against colonic diseases.

AREAS COVERED

In this review, we introduce the structure and composition of colonic mucus as well as its impact on the bioavailability of oral drugs. We also introduce various technologies used in the construction of mucus-penetrating nanomedicines (e.g. surface modification of polymers, physical means and biological strategies) and discuss their mechanisms and potential techniques for improving mucus penetration of nanotherapeutics.

EXPERT OPINION

The mucus barrier is often overlooked in oral drug delivery. The weak mucus permeability of conventional medications greatly lowers drug bioavailability. This challenge can be addressed through physical, chemical and biological technologies. In addition to the reported methods, promising approaches may be discovered through interdisciplinary research that further helps enhance the mucus penetration of nanomedicines.

Oral nanoparticulate drug delivery systems for the treatment of intestinal bowel disease and colorectal cancer

INTRODUCTION

The most popular method for delivering drugs locally and systemically is oral. However, the gastrointestinal tract's severe physiological (mucosal and enzymatic barrier) and physicochemical (pH) environment places restrictions on the oral drug delivery system's bioavailability and targeted design.

AREAS COVERED

Various nanoparticulate drug delivery systems (NPDDSs) based on lipids or polymers, such as liposomes, solid lipid nanoparticles, polymeric micelles, nanospheres, and nanocapsules and their application in successful treatment of serious diseases such as intestinal bowel disease and colorectal cancer (CRC). These systems can ensure advantages over conventional systems liked improved bioavailability, prolonged residence time, and enhanced solubility of poorly soluble drugs. Moreover, the nature of these NPDDSs led to numerous breakthroughs in bioavailability, active and passive targeting, controlled release, and cost-efficient production on an industrial scale in recent years.

EXPERT OPINION

An expert opinion on orally administrable lipid and polymer based NPDDS, the physiological barriers and their use in the treatment of intestinal bowel disease and CRC is provided within this review.

Plant Exosome-like Nanovesicles and Their Role in the Innovative Delivery of RNA Therapeutics

Exosomes are single membrane-bound spheres released from cells carrying complex cargoes, including lipids, proteins, and nucleic acids. Exosomes transfer specific cargoes from donor to acceptor cells, playing important roles in cell-to-cell communication. Current studies have reported that plant exosomes are prominent in transferring small RNA between host and pathogens in a cross-kingdom manner. Plant exosomes are excellent RNA interference (RNAi) delivery agents with similar physical and chemical properties to mammalian exosomes and have potential applications in therapeutic delivery systems. Recent data have suggested that plant exosome-like nanovesicles (PENVs) and artificial PENV-derived nano-vectors (APNVs) are beneficial for delivering therapeutic small RNA in mammalian systems and exhibit excellent competitiveness in future clinical applications. This review features their preparation methods, composition, roles in small RNA delivery for health functionalities, and their potency as functional nanomedicine.

Plant-Derived Extracellular Vesicles and Their Exciting Potential as the Future of Next-Generation Drug Delivery

Plant cells release tiny membranous vesicles called extracellular vesicles (EVs), which are rich in lipids, proteins, nucleic acids, and pharmacologically active compounds. These plant-derived EVs (PDEVs) are safe and easily extractable and have been shown to have therapeutic effects against inflammation, cancer, bacteria, and aging. They have shown promise in preventing or treating colitis, cancer, alcoholic liver disease, and even COVID-19. PDEVs can also be used as natural carriers for small-molecule drugs and nucleic acids through various administration routes such as oral, transdermal, or injection. The unique advantages of PDEVs make them highly competitive in clinical applications and preventive healthcare products in the future. This review covers the latest methods for isolating and characterizing PDEVs, their applications in disease prevention and treatment, and their potential as a new drug carrier, with special attention to their commercial viability and toxicological profile, as the future of nanomedicine therapeutics. This review champions the formation of a new task force specializing in PDEVs to address a global need for rigor and standardization in PDEV research.

Advanced Delivery System of Polyphenols for Effective Cancer Prevention and Therapy

Polyphenols from plants such as fruits and vegetables are phytochemicals with physiological and pharmacological activity as potential drugs to modulate oxidative stress and inflammation associated with cardiovascular disease, chronic disease, and cancer. However, due to the limited water solubility and bioavailability of many natural compounds, their pharmacological applications have been limited. Researchers have made progress in the development of nano- and micro-carriers that can address these issues and facilitate effective drug delivery. The currently developed drug delivery systems maximize the fundamental effects in various aspects such as absorption rate, stability, cellular absorption, and bioactivity of polyphenols. This review focuses on the antioxidant and anti-inflammatory effects of polyphenols enhanced by the introduction of drug delivery systems, and ultimately discusses the inhibition of cancer cell proliferation, growth, and angiogenesis.

The Role of Seaweed Polysaccharides in Gastrointestinal Health: Protective Effect against Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a prominent global public health issue. Anti-inflammatory medications, immunosuppressants, and biological therapies are currently used as treatments. However, they are often unsuccessful and have negative consequences on human health. Thus, there is a tremendous demand for using natural substances, such as seaweed polysaccharides, to treat IBD's main pathologic treatment targets. The cell walls of marine algae are rich in sulfated polysaccharides, including carrageenan in red algae, ulvan in green algae, and fucoidan in brown algae. These are effective candidates for drug development and functional nutrition products. Algal polysaccharides treat IBD through therapeutic targets, including inflammatory cytokines, adhesion molecules, intestinal epithelial cells, and intestinal microflora. This study aimed to systematically review the potential therapeutic effects of algal polysaccharides on IBD while providing the theoretical basis for a nutritional preventive mechanism for IBD and the restoration of intestinal health. The results suggest that algal polysaccharides have significant potential in complementary IBD therapy and further research is needed for fully understanding their mechanisms of action and potential clinical applications.

Surface design of nanocarriers: Key to more efficient oral drug delivery systems

As nanocarriers (NCs) can improve the solubility of drugs, prevent their degradation by gastrointestinal (GI) enzymes and promote their transport across the mucus gel layer and absorption membrane, the oral bioavailability of these drugs can be substantially enhanced. All these properties of NCs including self-emulsifying drug delivery systems (SEDDS), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, polymeric nanoparticles, inorganic nanoparticles and polymeric micelles depend mainly on their surface chemistry. In particular, interaction with food, digestive enzymes, bile salts and electrolytes, diffusion behaviour across the mucus gel layer and fate on the absorption membrane are determined by their surface. Bioinert surfaces limiting interactions with gastrointestinal fluid and content as well as with mucus, adhesive surfaces providing an intimate contact with the GI mucosa and absorption enhancing surfaces can be designed. Furthermore, charge converting surfaces shifting their zeta potential from negative to positive directly at the absorption membrane and surfaces providing a targeted drug release are advantageous. In addition to these passive surfaces, even active surfaces cleaving mucus glycoproteins on their way through the mucus gel layer can be created. Within this review, we provide an overview on these different surfaces and discuss their impact on the performance of NCs in the GI tract.

Biodegradable Polymeric Nanoparticles Loaded with Flavonoids: A Promising Therapy for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a group of disorders that cause chronic non-specific inflammation in the gastrointestinal (GI) tract, primarily affecting the ileum and colon. The incidence of IBD has risen sharply in recent years. Despite continuous research efforts over the past decades, the aetiology of IBD is still not fully understood and only a limited number of drugs are available for its treatment. Flavonoids, a ubiquitous class of natural chemicals found in plants, have been widely used in the prevention and treatment of IBD. However, their therapeutic efficacy is unsatisfactory due to poor solubility, instability, rapid metabolism, and rapid systemic elimination. With the development of nanomedicine, nanocarriers can efficiently encapsulate various flavonoids and subsequently form nanoparticles (NPs), which greatly improves the stability and bioavailability of flavonoids. Recently, progress has also been made in the methodology of biodegradable polymers that can be used to fabricate NPs. As a result, NPs can significantly enhance the preventive or therapeutic effects of flavonoids on IBD. In this review, we aim to evaluate the therapeutic effect of flavonoid NPs on IBD. Furthermore, we discuss possible challenges and future perspectives.

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.

Eudragit-coated chitosan-tripterygium glycoside conjugate microspheres alleviate DSS-induced experimental colitis by inhibiting the TLR4/NF-κB signaling pathway

OBJECTIVE

Tripterygium glycoside (TG) is a fat-soluble extract of Tripterygium wilfordii, with anti-inflammatory properties associated with TLR signaling pathways. This study constructed a targeted delivery system for experimental colitis, namely, eudragit (EuL)-coated chitosan (Ch)-TG conjugate microspheres (Ch-TG-MS/EuL), and evaluated its therapeutic efficacy and underlying mechanisms.

METHODS

Ch-TG-MS was fabricated using emulsification cross-linking technique and then coated with EuL to create Ch-TG-MS/EuL. Drug release properties were assessed using a dialysis model. Additionally, the therapeutic benefits of Ch-TG-MS/EuL on colonic inflammation and its specific effect on TLR4/NF-κB signaling in intestinal mucosa were evaluated in vivo using a DSS-induced murine colitis model.

RESULTS

The Ch-TG-MS/EuL microspheres appeared as yellow powders with a slightly enlarged shape, rough surface, and adhesions. The Ch-TG-MS/EuL formulations also exhibited high entrapment efficiency and drug loading rate. High-performance liquid chromatography revealed that Ch-TG-MS/EuL exhibited a less intense peak than free TG, confirming that the drug is contained within the formulation. Free TG displayed explosive release within the first 5 h of administration, while Ch-TG-MS/EuL prevented the pre-mature release of TG and exhibited controllable release up to 24 h. In vivo, noticeable amelioration of intestinal mucosal tissue destruction was achieved with Ch-TG-MS/EuL compared to free TG. Additionally, immunohistochemical and western blotting results revealed that Ch-TG-MS/EuL markedly down-regulated the expression of intestinal mucosal TLR4, MyD88, and NF-κB p65. Hence, Ch-TG-MS/EuL may ameliorate the colon inflammatory response by inhibiting the hyperactivation of TLR4/NF-κB signaling.

CONCLUSION

Novel Ch-TG-MS/EuL preparation may represent a colonic delivery system for UC therapeutics by inhibiting TLR4/NF-κB hyperactivation.

DATA AVAILABILITY

All experimental data supporting the conclusions of this study are available from the corresponding author on reasonable request.

Synthetic Lignin-Derived Therapeutic Nano Reagent as Intestinal pH-Sensitive Drug Carriers Capable of Bypassing the Gastric Acid Environment for Colitis Treatment

Oral drug delivery is a common route for management of inflammatory bowel disease (IBD) but suffers from low bioavailability and systemic side effects during passage through the alimentary canal. Here, we present a therapeutic nano reagent of a ferulic acid-derived lignin nanoparticle (FALNP). We showed that FALNP with favorable antioxidant activity can regulate IBD. More importantly, the intestinal pH-responsive degradability of FALNP allows it to withstand the harsh gastric acid environment, bypass physiological barriers, and target the intestine for gastrointestinal delivery. In vivo experiments showed that oral administration of FALNP markedly relieved pathological symptoms in a mouse model of acute colitis by reducing oxidative stress and regulating the gut microbiome. By integrating anti-inflammatory medicine, FALNP also can be used as a bioactive carrier to exert a potent synergistic therapeutic effect. In addition to colitis, FALNP can be readily adaptable for use as a carrier platform for therapy of many other intestinal diseases.

Preparation and Characterization of a Novel Multiparticulate Dosage Form Carrying Budesonide-Loaded Chitosan Nanoparticles to Enhance the Efficiency of Pellets in the Colon

An attempt was made to conquer the limitation of orally administered nanoparticles for the delivery of budesonide to the colon. The ionic gelation technique was used to load budesonide on chitosan nanoparticles. The nanoparticles were investigated in terms of size, zeta potential, encapsulation efficiency, shape and drug release. Then, nanoparticles were pelletized using the extrusion-spheronization method and were investigated for their size, mechanical properties, and drug release. Pellets were subsequently coated with a polymeric solution composed of two enteric (eudragit L and S) and time-dependent polymers (eudragit RS) for colon-specific delivery. All formulations were examined for their anti-inflammatory effect in rats with induced colitis and the relapse of the colitis after discontinuation of treatment was also followed. The size of nanoparticles ranged between 288 ± 7.5 and 566 ± 7.7 nm and zeta potential verified their positive charged surface. The drug release from nanoparticles showed an initial burst release followed by a continuous release. Pelletized nanoparticles showed proper mechanical properties and faster drug release in acidic pH compared with alkaline pH. It was interesting to note that pelletized budesonide nanoparticles released the drug throughout the GIT in a sustained fashion, and had long-lasting anti-inflammatory effects while rapid relapse was observed for those treated with conventional budesonide pellets. It seems that there is a synergistic effect of nanoformulation of budesonide and the encapsulation of pelletized nanoparticles in a proper coating system for colon delivery that could result in a significant and long-lasting anti-inflammatory effect.

An oral delivery vehicle based on konjac glucomannan acetate targeting the colon for inflammatory bowel disease therapy

Orally administered colon-targeted delivery vehicles are of major importance in the treatment of inflammatory bowel disease (IBD). However, it remains a challenge to maintain the integrity of such delivery vehicles during treatment, particularly in the gastric environment, which may cause untimely drug release before reaching the targeted colon. Herein, an oral colon-targeted drug delivery system (OCDDS) based on acetylated konjac glucomannan (AceKGM) has been developed in this work, which accomplishes colonic localization release and targets local inflammatory macrophages. The AceKGM nanoparticle-loading curcumin (Cur) was successfully fabricated by emulsion solvent evaporation techniques. DLS, AFM, and SEM were used in order to evaluate the nanoparticles’ diameter as well as their in vitro drug release profile, and reactive oxygen species (ROS) scavenging results showed that the OCDDS considerably retained the activity of Cur treated with simulated gastric fluid (SGF) and controllably released in simulated intestinal fluid (SIF). In addition, the adhesion experiment results indicated that the nanoparticle could accumulate on the colonic macrophages. Evaluations in colitis mice showed that the treatment significantly alleviated the symptoms of colitis by decreasing the local level of myeloperoxidase (MPO) and the disease activity index (DAI) score in mice. In summary, the results of our research demonstrate that Cur–AceKGM nanoparticles exhibit significantly improved therapeutic efficacy compared to orally administered free Cur and can be developed as an effective drug delivery vehicle for IBD treatment.

Annexin A1 based inflammation resolving mediators and nanomedicines for inflammatory bowel disease therapy

Inflammatory bowel diseases (IBD) such as Crohn's Disease (CD) and Ulcerative Colitis (UC) are chronic, progressive, and relapsing disorders of the gastrointestinal tract (GIT), characterised by intestinal epithelial injury and inflammation. Current research shows that in addition to traditional anti-inflammatory therapy, resolution of inflammation and repair of the epithelial barrier are key biological requirements in combating IBD. Resolution mediators include endogenous lipids that are generated during inflammation, e.g., lipoxins, resolvins, protectins, maresins; and proteins such as Annexin A1 (ANXA1). Nanoparticles can specifically deliver these potent inflammation resolving mediators in a spatiotemporal manner to IBD lesions, effectively resolve inflammation, and promote a return to homoeostasis with minimal collateral damage. We discuss these exciting and timely concepts in this review.

Oral delivery of IL-22 mRNA-loaded lipid nanoparticles targeting the injured intestinal mucosa: A novel therapeutic solution to treat ulcerative colitis

Oral mRNA delivery is a promising yet understudied approach for treating inflammatory bowel disease (IBD). Inspired by the colon-targeting ability of ginger-derived nanoparticles (GDNPs), we reversely engineered lipid nanoparticles that comprise the three major lipids identified in GDNPs. When mixed at the ratio found in GDNPs, the selected lipids (phosphatidic acid, monogalactosyldiacylglycerol, and digalactosyldiacylglycerol; 5:2:3) self-assembled into new lipid nanoparticles (nLNPs) in phosphate-buffered saline. We encapsulated IL-22-mRNA within the nLNPs, as enhanced IL-22 expression in the colon is known to have potent anti-inflammatory efficacy against ulcerative colitis (UC). The IL-22 mRNA-loaded nLNPs (IL-22/nLNPs) were found to be about 200 nm in diameter and have a zeta potential of -18 mV. Oral delivery of IL-22/nLNPs elevated the protein expression level of IL-22 in the colonic mucosa of mice. In a mouse model of acute colitis, mice fed with IL-22/nLNPs experienced an accelerated healing process, as indicated by the recovery of more body weight and colon length as well as reduction of the histological index, colonic MPO activity, fecal lipocalin concentration, and mRNA expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β). Our results suggest that our reversely engineered nLNPs is an excellent mRNA delivery platform for treating ulcerative colitis.

Mo3Se4 nanoparticle with ROS scavenging and multi-enzyme activity for the treatment of DSS-induced colitis in mice

Ulcerative colitis (UC), as a most common inflammatory bowel disease (IBD), has become a global public health concern. Exploring novel method of treating UC is urgent and necessary. Recently, nanozyme with excellent antioxidant properties may be one useful therapeutic strategy. In this study, a two-dimensional transition metal chalcogenide (TMCs) nano flake and polyethylene glycol (PEG) modified Mo₃Se₄ nano flakes (PMNFs) was synthesized, which had multi-enzyme activity, including peroxidase, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). The inhibition effect of PMNFs on sodium dextran sulfate (DSS)-induced colitis was explored. UC was effectively inhibited by PMNFs in this work. PMNFs significantly reduced disease activity index (DAI) score, including weight loss, colon shorten and histopathological abnormalities. The possible mechanism of PMNFs-attenuated colitis was investigated. The results showed that PMNFs reversed DSS-induced oxidative damage, and the antioxidant pathway Nrf2-keap1 signal was activated by PMNFs. Moreover, PMNFs suppressed the expression of pro-inflammatory factors including IL-1β, TNF-α, IFN-β and IL-6 via the inactivation of TLR4/NF-κB pathway in DSS-induced colitis and LPS-treated macrophage. Furthermore, PMNFs treatment prevented the reduction of tight junction proteins (ZO-1, occludin, and claudin-1) and mucin-2 (MUC-2) as well as the up-regulation of epithelial apoptosis caused by DSS. These findings demonstrate that the PMNFs against DSS-induced colitis due to its prevention on oxidative damage, inflammation, and intestine barrier breakdown. Thus, PMNFs have a potential application in the treatment of various oxidative stress or inflammation-related diseases.

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Mo₃Se₄ nano flakes (PMNFs) can effective scavenge ROS in vivo and in vitro.

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PMNFs have multi-enzyme activity, including the peroxidase, GPx, SOD, and CAT.

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PMNFs can prevent symptoms of colitis induced by DSS in mice.

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PMNFs against DSS-induced colitis through prevention on oxidative damage, inflammation, and intestine barrier breakdown.

Novel nano-encapsulated probiotic agents: Encapsulate materials, delivery, and encapsulation systems

Gut microbes are closely associated with most human health. When ingested orally, probiotics can effectively regulate the composition and quantity of human intestinal microorganisms, which is beneficial to human health. However, probiotics will be affected by the harsh environment of the digestive tract during the in vivo transportation process, and ensuring the viability of probiotics is a great challenge. Probiotic encapsulating technology provides an effective solution to this problem. The introduction of extreme temperatures, large probiotic microcapsule sizes and the difficulty in controlling probiotic microcapsule particle sizes mean that traditional microcapsule encapsulation methods have some limitations. From traditional microcapsule technology to the bulk encapsulation of probiotics with nanofibers and nanoparticles to the recent ability to wear nano "armor" for a single probiotic through biofilm, biological membrane and nanocoating. Emerging probiotic nanoagents provides a new conceptual and development direction for the field of probiotic encapsulation. In this review, we presented the characteristics of encapsulated probiotic carrier materials and digestive tract transport systems, we focused on the encapsulation systems of probiotic nanoagents, we analyzed the shortcomings and advantages of the current agent encapsulation systems, and we stated the developmental direction and challenges for these agents for the future.

Focusing on Future Applications and Current Challenges of Plant Derived Extracellular Vesicles

Plant derived extracellular vesicles (EVs) are nano-sized membranous vesicles released by plant cells, which contain lipids, proteins, nucleic acids and specific pharmacologically active substances. They are safe, widely available and expediently extractive. They have gratifyingly biological activity against inflammation, cancer, bacteria and oxidative aging, especially for the prevention or treatment of colitis, cancer, alcoholic liver, and COVID-19. In addition, as natural drug carriers, plant derived EVs have the potential to target the delivery of small molecule drugs and nucleic acid through oral, transdermal, injection. With the above advantages, plant derived EVs are expected to have excellent strong competitiveness in clinical application or preventive health care products in the future. We comprehensively reviewed the latest separation methods and physical characterization techniques of plant derived EVs, summarized the application of them in disease prevention or treatment and as a new drug carrier, and analyzed the clinical application prospect of plant derived EVs as a new drug carrier in the future. Finally, the problems hindering the development of plant derived EVs at present and consideration of the standardized application of them are discussed.