Explore the underlying oral efficacy of α-, β-, γ-Cyclodextrin against the ulcerative colitis using in vitro and in vivo studies assisted by network pharmacology

The incidence of ulcerative colitis (UC) is rising worldwide. As a refractory and recurrent disease, UC could seriously affect the patients' quality of life. However, current clinical medical treatments for UC are accompanied by various side effects, especially for long-term applications. Here, the underlying efficacy of cyclodextrins (CDs) was studied. As common excipients, CDs endow proven safety for long-term applications. Results of predictive methods derived from network pharmacology prompted the potential anti-inflammatory effects of CDs by oral administration. RAW264.7 cell experiments verified that CDs could inhibit the excessive secretion of TNF-α (β-CD > α-CD ≈ γ-CD), IL-6, and NO (α-CD > β-CD ≈ γ-CD) as predicted. In mice with DSS-induced acute UC, oral administration of CDs could effectively mitigate the pathological damage of colon tissue and reduce the level of inflammatory mediators. Moreover, 16S rRNA sequencing displayed that gut microbes disturbed by DSS were significantly regulated by CDs. Conclusively, the study showed the therapeutic application prospects of CDs in UC treatment and indicated the feasibility and advantages of developing 'new' therapeutic activities of 'old' ingredients.Communicated by Ramaswamy H. Sarma.

Recent developments and new directions in the use of natural products for the treatment of inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) represents a significant global health challenge, and there is an urgent need to explore novel therapeutic interventions. Natural products have demonstrated highly promising effectiveness in the treatment of IBD.

PURPOSE

This study systematically reviews the latest research advancements in leveraging natural products for IBD treatment.

METHODS

This manuscript strictly adheres to the PRISMA guidelines. Relevant literature on the effects of natural products on IBD was retrieved from the PubMed, Web of Science and Cochrane Library databases using the search terms "natural product," "inflammatory bowel disease," "colitis," "metagenomics", "target identification", "drug delivery systems", "polyphenols," "alkaloids," "terpenoids," and so on. The retrieved data were then systematically summarized and reviewed.

RESULTS

This review assessed the different effects of various natural products, such as polyphenols, alkaloids, terpenoids, quinones, and others, in the treatment of IBD. While these natural products offer promising avenues for IBD management, they also face challenges in terms of clinical translation and drug discovery. The advent of metagenomics, single-cell sequencing, target identification techniques, drug delivery systems, and other cutting-edge technologies heralds a new era in overcoming these challenges.

CONCLUSION

This paper provides an overview of current research progress in utilizing natural products for the treatment of IBD, exploring how contemporary technological innovations can aid in discovering and harnessing bioactive natural products for the treatment of IBD.

Recent progress on engineered micro/nanomaterials mediated modulation of gut microbiota for treating inflammatory bowel disease

Inflammatory bowel disease (IBD) is a type of chronic recurrent inflammation disease that mainly includes Crohn's disease and ulcerative colitis. Currently, the treatments for IBD remain highly challenging, with clinical treatment drugs showing limited efficacy and adverse side effects. Thus, developing drug candidates with comprehensive therapeutic effects, high efficiency, and low toxicity is urgently needed. Recently, micro/nanomaterials have attracted considerable interest because of their bioavailability, multitarget and efficient effects on IBD. In addition, gut modulation plays a substantial role in restoring intestinal homeostasis. Therefore, efficient microbiota-based strategies modulating gut microenvironment have great potential in remarkably treating IBD. With the development of micro- and nanomaterials for the treatment of IBD and more in-depth studies of their therapeutic mechanisms, it has been found that these treatments also have a tendency to positively regulate the intestinal flora, resulting in an increase in the beneficial flora and a decrease in the level of pathogenic bacteria, thus regulating the composition of the intestinal flora to a normal state. In this review, we first present the interactions among the immune system, intestinal barrier, and gut microbiome. In addition, recent advances in administration routes and methods that positively arouse the regulation of intestinal flora for IBD using probiotics, prebiotics, and redox-active micro/nanomaterials have been reviewed. Finally, the key challenges and critical perspectives of gut microbiota-based micro/nanomaterial treatment are also discussed.

The development of nanocarriers for natural products

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

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.

Hyaluronic acid-functionalized DDAB/PLGA nanoparticles for improved oral delivery of magnolol in the treatment of ulcerative colitis

Dysfunction of the mucosal barrier as well as local inflammation are major challenges in the treatment of ulcerative colitis (UC). Mag, a natural compound derived from traditional Chinese medicine, has been shown to have anti-inflammatory and mucosal protection properties. However, its poor gastrointestinal stability as well as its insufficient accumulation in inflamed colonic lesions limit its potential use as an alternative therapeutic drug in UC. The present research involved the design and preparation of a hybrid nanoparticle system (LPNs) specifically targeting macrophages at the colonic site. This was achieved by electrostatically adsorbing HA onto positively charged lipid-polymer hybrid nanoparticles (HA-LPNs). The prepared HA-LPNs exhibited a rounded morphology and a narrow size distribution. In vitro, the anti-inflammatory efficacy of Mag-HA-LPNs (which control levels of the pro-inflammatory cytokines NO, IL-6 and TNF-α) was assessed in RAW 264.7 cells. Analysis by flow cytometry and fluorescence microscopy demonstrated increased cellular uptake through HA/CD44 interaction. As expected, Mag-HA-LPNs was found to effectively increased colon length and reduced DAI scores in DSS-treated mice. This effect was achieved by regulating the inflammatory cytokines level and promoting the restoration of the colonic mucosal barrier through increased expression of Claudin-1, ZO-1 and Occludin. In this study, we developed an efficient and user-friendly delivery method for the preparation of HA-functionalized PLGA nanoparticles, which are intended for oral delivery of Mag. The findings suggest that these HA-LPNs possess the potential to serve as a promising approach for direct drug delivery to the colon for effective treatment of UC.

Pulmonary RNA interference against acute lung injury mediated by mucus- and cell-penetrating nanocomplexes

Trans-mucosal delivery of anti-inflammatory siRNA into alveolar macrophages represents a promising modality for the treatment of acute lung injury (ALI). However, its therapeutic efficacy is often hurdled by the lack of effective carriers that can simultaneously overcome the mucosal barrier and cell membrane barrier. Herein, we developed mucus/cell membrane dual-penetrating, macrophage-targeting polyplexes which enabled efficient intratracheal delivery of TNF-α siRNA (siTNF-α) to attenuate pulmonary inflammation against lipopolysaccharide (LPS)-induced ALI. P-G@Zn, a cationic helical polypeptide bearing both guanidine and zinc dipicolylamine (Zn-DPA) side charged groups, was designed to condense siTNF-α and promote macrophage internalization due to its helicity-dependent membrane activity. Coating of the polyplexes with charge-neutralizing carboxylated mannan (Man-COOH) greatly enhanced the mucus penetration potency due to shielding of the electrostatic adhesive interactions with the mucus, and it cooperatively enabled active targeting to alveolar macrophages to potentiate the intracellular delivery efficiency of siTNF-α. As such, intratracheally administered Man-COOH/P-G@Zn/siTNF-α polyplexes provoked notable TNF-α silencing by ∼75 % in inflamed lung tissues at 500 μg siRNA/kg, and demonstrated potent anti-inflammatory performance to treat ALI. This study provides an effective tool for the synchronized trans-mucosal delivery of siRNA into macrophages, and the unique properties of the polyplexes render remarkable potentials for anti-inflammatory therapy against ALI. STATEMENT OF SIGNIFICANCE: siRNA-mediated anti-inflammatory management of acute lung injury (ALI) is greatly challenged by the insufficient delivery across the mucus layer and cell membrane. To address such critical issue, mucus/cell membrane dual-penetrating, macrophage-targeting polyplexes are herein developed, which are comprised of an outer shell of carboxylated mannan (Man-COOH) and an inner nanocore formed by TNF-α siRNA (siTNF-α) and a cationic helical polypeptide P-G@Zn. Man-COOH coating endowed the polyplexes with high mucus-penetrating capability and macrophage-targeting ability, while P-G@Zn bearing both guanidine and zinc dipicolylamine afforded potent siTNF-α condensation capacity and high intracellular delivery efficiency with reduced cytotoxicity. Intratracheally administered polyplexes solicit pronounced TNF-α silencing and anti-inflammatory efficiencies in ALI mice. This study renders an effective example for overcoming the multiple barriers against trans-mucosal delivery of siRNA into macrophages, and holds profound potentials for gene therapy against ALI.

Berberine prevents NAFLD and HCC by modulating metabolic disorders

Non-alcoholic fatty liver disease (NAFLD) is a global metabolic disease with high prevalence in both adults and children. Importantly, NAFLD is becoming the main cause of hepatocellular carcinoma (HCC). Berberine (BBR), a naturally occurring plant component, has been demonstrated to have advantageous effects on a number of metabolic pathways as well as the ability to kill liver tumor cells by causing cell death and other routes. This permits us to speculate and make assumptions about the value of BBR in the prevention and defense against NAFLD and HCC by a global modulation of metabolic disorders. Herein, we briefly describe the etiology of NAFLD and NAFLD-related HCC, with a particular emphasis on analyzing the potential mechanisms of BBR in the treatment of NAFLD from aspects including increasing insulin sensitivity, controlling the intestinal milieu, and controlling lipid metabolism. We also elucidate the mechanism of BBR in the treatment of HCC. More significantly, we provided a list of clinical studies for BBR in NAFLD. Taking into account our conclusions and perspectives, we can make further progress in the treatment of BBR in NAFLD and NAFLD-related HCC.

Orally-administered nanomedicine systems targeting colon inflammation for the treatment of inflammatory bowel disease: latest advances

Inflammatory bowel disease (IBD) is a chronic and idiopathic condition that results in inflammation of the gastrointestinal tract, leading to conditions such as ulcerative colitis and Crohn's disease. Commonly used treatments for IBD include anti-inflammatory drugs, immunosuppressants, and antibiotics. Fecal microbiota transplantation is also being explored as a potential treatment method; however, these drugs may lead to systemic side effects. Oral administration is preferred for IBD treatment, but accurately locating the inflamed area in the colon is challenging due to multiple physiological barriers. Nanoparticle drug delivery systems possess unique physicochemical properties that enable precise delivery to the target site for IBD treatment, exploiting the increased permeability and retention effect of inflamed intestines. The first part of this review comprehensively introduces the pathophysiological environment of IBD, covering the gastrointestinal pH, various enzymes in the pathway, transport time, intestinal mucus, intestinal epithelium, intestinal immune cells, and intestinal microbiota. The second part focuses on the latest advances in the mechanism and strategies of targeted delivery using oral nanoparticle drug delivery systems for colitis-related fields. Finally, we present challenges and potential directions for future IBD treatment with the assistance of nanotechnology.

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.

Oral administration of Huanglian-Houpo herbal nanoemulsion loading multiple phytochemicals for ulcerative colitis therapy in mice

How to achieve stable co-delivery of multiple phytochemicals is a common problem. This study focuses on the development, optimization and characterization of Huanglian-HouPo extract nanoemulsion (HLHPEN), with multiple components co-delivery, to enhance the anti-ulcerative colitis (UC) effects. The formulation of HLHPEN was optimized by pseudo-ternary phase diagram combined with Box-Behnken design. The physicochemical properties of HLHPEN were characterized, and its anti-UC activity was evaluated in DSS-induced UC mice model. Based on preparation process optimization, the herbal nanoemulsion HLHPEN was obtained, with the droplet size, PDI value, encapsulation efficiency (EE) for 6 phytochemicals (berberine, epiberberine, coptisine, bamatine, magnolol and honokiol) of 65.21 ± 0.82 nm, 0.182 ± 0.016, and 90.71 ± 0.21%, respectively. The TEM morphology of HLHPEN shows the nearly spheroidal shape of particles. The optimized HLHPEN showed a brownish yellow milky single-phase and optimal physical stability at 25 °C for 90 days. HLHPEN exhibited the good particle stability and gradual release of phytochemicals in SGF and SIF, to resist the destruction of simulated stomach and small intestine environment. Importantly, the oral administration of HLHPEN significantly restored the shrunk colon tissue length and reduced body weight, ameliorated DAI value and colon histological pathology, decreased the levels of inflammatory factors in DSS-induced UC mice model. These results demonstrated that HLHPEN had a significant therapeutic effect on DSS-induced UC mice, as a potential alternative UC therapeutic agent.

Oral Administration of Platinum Nanoparticles with SOD/CAT Cascade Catalytic Activity to Alleviate Ulcerative Colitis

Ulcerative colitis (UC) is a refractory chronic inflammatory disease involving the colon and rectum, falling under the category of inflammatory bowel disease (IBD). The accumulation of reactive oxygen species (ROS) in local tissues has been identified as a crucial contributor to the escalation of inflammatory responses. Therefore, eliminating ROS in the inflamed colon is a promising approach to treating UC. Nanomaterials with intrinsic enzyme-like activities (nanozymes) have shown significant therapeutic potential in UC. In this study, we found that platinum nanoparticles (Pt NPs) exhibited remarkable superoxide dismutase (SOD) and catalase (CAT) cascade catalytic activities, as well as effective hydroxyl radical (•OH) scavenging ability. The in vitro experiments showed that Pt NPs could eliminate excessive ROS to protect cells against oxidative stress. In the colitis model, oral administration of Pt NPs (loaded in chitosan/alginate hydrogel) could significantly alleviate UC, including reducing the colon length, the damaged epithelium, and the infiltration of inflammatory cells. Without appreciable systemic toxicity, Pt NPs represent a novel therapeutic approach to UC and are expected to achieve long-term inflammatory remission.

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

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

Colon-targeted delivery of polyphenols: construction principles, targeting mechanisms and evaluation methods

Polyphenols have received considerable attention for their promotive effects on colonic health. However, polyphenols are mostly sensitive to harsh gastrointestinal environments, thus, must be protected. It is necessary to design and develop a colon-targeted delivery system to improve the stability, colon-targeting and bioavailability of polyphenols. This paper mainly introduces research on colon-targeted controlled release of polyphenols. The physiological features affecting the dissolution, release and absorption of polyphenol-loaded delivery systems in the colon are first discussed. Simultaneously, the types of colon-targeted carriers with different release mechanisms are described, and colon-targeting assessment models that have been studied so far and their advantages and limitations are summarized. Based on the current research on polyphenols colon-targeting, outlook and reflections are proposed, with the goal of inspiring strategic development of new colon-targeted therapeutics to ensure that the polyphenols reach the colon with complete bioactivity.

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.

Bio-adhesive and ROS-scavenging hydrogel microspheres for targeted ulcerative colitis therapy

Ulcerative colitis (UC) as an important type of inflammatory bowel disease is a chronic disease characterized by intestinal dyshomeostasis. The UC treatment is challenged by the insufficiency of drug delivery and retention. Herein, we fabricated an intrarectal formulation of olsalazine (Olsa)-loaded hydrogel microspheres (LDKT/Olsa) with good bio-adhesiveness and reactive oxygen species (ROS)-scavenging ability to enhance drug retention and therapeutic effect. Low methoxy pectin-dopamine conjugate/konjac glucomannan composite hydrogel microspheres (LDKT) with a size ranging from 10 to 100 μm were prepared by using Zn²⁺ and ROS-sensitive thioketal as crosslinkers. Upon intrarectal administration, the negatively charged and dopamine-functionalized hydrogel microspheres efficiently adhered to cationic surface of inflammatory mucosa, scavenging ROS and releasing Zn²⁺ and Olsa for antibacterial and anti-inflammatory effects. In the dextran sodium sulfate (DSS)-induced mouse UC model, the microspheres significantly reduced the levels of colonic ROS and pro-inflammatory cytokines, improved gut mucosal barrier integrity, and remarkably relieved colitis. Overall, the LDKT microspheres are promising carriers to deliver drugs for UC treatment.

κ-Selenocarrageenan Oligosaccharides Prepared by Deep-Sea Enzyme Alleviate Inflammatory Responses and Modulate Gut Microbiota in Ulcerative Colitis Mice

κ-Selenocarrageenan (KSC) is an organic selenium (Se) polysaccharide. There has been no report of an enzyme that can degrade κ-selenocarrageenan to κ-selenocarrageenan oligosaccharides (KSCOs). This study explored an enzyme, κ-selenocarrageenase (SeCar), from deep-sea bacteria and produced heterologously in Escherichia coli, which degraded KSC to KSCOs. Chemical and spectroscopic analyses demonstrated that purified KSCOs in hydrolysates were composed mainly of selenium-galactobiose. Organic selenium foods through dietary supplementation could help regulate inflammatory bowel diseases (IBD). This study discussed the effects of KSCOs on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in C57BL/6 mice. The results showed that KSCOs alleviated the symptoms of UC and suppressed colonic inflammation by reducing the activity of myeloperoxidase (MPO) and regulating the unbalanced secretion of inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10). Furthermore, KSCOs treatment regulated the composition of gut microbiota, enriched the genera Bifidobacterium, Lachnospiraceae_NK4A136_group and Ruminococcus and inhibited Dubosiella, Turicibacter and Romboutsia. These findings proved that KSCOs obtained by enzymatic degradation could be utilized to prevent or treat UC.

Orally administration of cerium oxide nanozyme for computed tomography imaging and anti-inflammatory/anti-fibrotic therapy of inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic nonspecific disease with unknown etiology. Currently, the anti-inflammatory therapeutic approaches have achieved a certain extent of effects in terms of inflammation alleviation. Still, the final pathological outcome of intestinal fibrosis has not been effectively improved yet.

RESULTS

In this study, dextran-coated cerium oxide (D-CeO₂) nanozyme with superoxide dismutase (SOD) and catalase (CAT) activities was synthesized by chemical precipitation. Our results showed that D-CeO₂ could efficiently scavenge reactive oxide species (ROS) as well as downregulate the pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and iNOS) to protect cells from H₂O₂-induced oxidative damage. Moreover, D-CeO₂ could suppress the expression of fibrosis-related gene levels, such as α-SMA, and Collagen 1/3, demonstrating the anti-fibrotic effect. In both TBNS- and DSS-induced colitis models, oral administration of D-CeO₂ in chitosan/alginate hydrogel alleviated intestinal inflammation, reduced colonic damage by scavenging ROS, and decreased inflammatory factor levels. Notably, our findings also suggested that D-CeO₂ reduced fibrosis-related cytokine levels, predicting a contribution to alleviating colonic fibrosis. Meanwhile, D-CeO₂ could also be employed as a CT contrast agent for noninvasive gastrointestinal tract (GIT) imaging.

CONCLUSION

We introduced cerium oxide nanozyme as a novel therapeutic approach with computed tomography (CT)-guided anti-inflammatory and anti-fibrotic therapy for the management of IBD. Collectively, without appreciable systemic toxicity, D-CeO₂ held the promise of integrated applications for diagnosis and therapy, pioneering the exploration of nanozymes with ROS scavenging capacity in the anti-fibrotic treatment of IBD.

The application of natural product-delivering micro/nano systems in the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a type of recurrent intestinal diseases. Natural product molecules have been gradually developed into an important source of anti-inflammatory drugs for treating IBD owing to their high anti-inflammatory activity, well known safety, structural specificity and therapeutic mechanism diversity. However, most of the natural products are restricted by poor solubility in actual application. How to achieve satisfactory bioavailability during the treatment of IBD is one of the urgent problems to be solved in the current research. Micro/nano drug delivery systems could improve the solubility of drugs with targeted delivery of anti-inflammatory drugs to the colon with responsive release property. Therefore, using micro/nano drug delivery systems, the problems mentioned above involving natural product molecules in the treatment of IBD could be solved. According to the compositions of the intestinal tract and inflammatory characteristics of IBD, the strategies of using micro/nano drug delivery systems for natural products could be summarized in two steps: targeted delivery and responsive release. In this review, the targeted and responsive release strategies of the micro/nano drug delivery systems combined with their anti-inflammatory effects in IBD animal models to illustrate that the proposed strategies could be potential treatments for symptomatic IBD are described.

Classical prescription Huanglian Decoction relieves ulcerative colitis via maintaining intestinal barrier integrity and modulating gut microbiota

BACKGROUND

Ulcerative colitis (UC) has affected an increasing number of people globally, with still limited clinical success. Huanglian Decoction (HLD) is a famous classical prescription documented for alleviating gastrointestinal disorders with unexplored therapeutic effects and mechanisms.

PURPOSE

This study aimed to investigate the therapeutic effect and underlying mechanism of HLD in dextran sodium sulfate (DSS)-induced colitis mice.

METHODS

The efficacy and safety of HLD were evaluated in a well-established DSS-induced colitis mice model. Disease progression was monitored via clinical symptoms, histopathological examination, biochemical assays, and epithelial barrier function evaluation.

RESULTS

HLD alleviated DSS-induced colitis symptoms, reversed colon length reduction, reduced histological injury, downregulated the level of pro-inflammatory cytokines, maintained the tight distribution of ZO-1/occludin-1 and the normal level of β-catenin, concurrent with apoptosis reduction in the colonic epithelium. After HLD treatment, the DSS-induced gut dysbiosis was modulated, and the gut microbiota achieved a new equilibrium state.

CONCLUSION

This study demonstrates that HLD may present a potential remedy for UC treatment, providing evidence for further developing Chinese classical prescriptions.

Gelatin-Based Electrospun Nanofibers Cross-Linked Using Horseradish Peroxidase for Plasmid DNA Delivery

The delivery of nucleic acids is indispensable for tissue engineering and gene therapy. However, the current approaches involving DNA/RNA delivery by systemic and local injections face issues such as clearance, off-target distribution, and tissue damage. In this study, we report plasmid DNA (pDNA) delivery using gelatin electrospun nanofibers obtained through horseradish peroxidase (HRP)-mediated insolubilization. The nanofibers were obtained through the electrospinning of an aqueous solution containing gelatin possessing phenolic hydroxyl (Ph) moieties (Gelatin-Ph) and HRP with subsequent HRP-mediated cross-linking of the Ph moieties by exposure to air containing 16 ppm H2O2 for 30 min. Then, Lipofectamine/pDNA complexes were immobilized on the nanofibers through immersion in the solution containing the pDNA complexes, resulting in transfection and sustained delivery of pDNA. Cells cultured on the resultant nanofibers expressed genome-editing molecules including Cas9 protein and guide RNA (gRNA), resulting in targeted gene knock-in and knock-out. These results demonstrated the potential of Gelatin-Ph nanofibers obtained through electrospinning and subsequent HRP-mediated cross-linking for gene therapy and tissue regeneration by genome editing.

Pharmacological effects of berberine on models of ulcerative colitis: A meta-analysis and systematic review of animal studies

Berberine (BBR) is the main active constituent of the Rhizoma coptidis (Huanglian) and has multiple biological activities. Although current evidence suggests that the BBR has a multi-target effect in ulcerative colitis (UC), its action and mechanism are unclear. The purpose of this meta-analysis was to assess the pharmacological effects and potential mechanisms of BBR in UC models. Studies were searched from four databases (PubMed, Embase, Web of Science, and Cochrane Library) until March 2022. Standardized mean difference (SMD) and 95% confidence intervals (CI) were used for the adjudication of outcomes. Stata 15.0 software was used for statistical analysis. Twenty-eight publications and 29 studies involving 508 animals were included in the meta-analysis. The results showed that BBR reduced disease activity index (DAI) scores, alleviated UC-induced colon length (CL) loss, prevented weight loss, and reduced histological colitis score (HCS). Mechanistically, BBR was found to reduce myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels, reduce levels of pro-inflammatory factors interleukin-1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), interferon-γ (IFN-γ) and mRNA expression of interleukin 17, increase levels of anti-inflammatory factor interleukin 10 (IL-10), and to increase levels of tight junction protein zonula occludens-1 (ZO-1) and occludin, which may involve antioxidant, anti-apoptotic, neuromodulation, anti-fibrotic, anti-inflammatory, barrier protection, and flora regulation aspects. However, additional attention should be paid to these outcomes due to the heterogeneity and methodological quality of the studies.

Anti-Oxidative and Anti-Inflammatory Micelles: Break the Dry Eye Vicious Cycle

Dry eye disease (DED) impacts ≈30% of the world's population and causes serious ocular discomfort and even visual impairment. Inflammation is one core cause of the DED vicious cycle, a multifactorial deterioration in DED process. However, there are also reactive oxygen species (ROS) regulating inflammation and other points in the cycle from the upstream, leading to treatment failure of current therapies merely targeting inflammation. Accordingly, the authors develop micelle-based eye drops (more specifically p38 mitogen-activated protein kinases (MAPK) inhibitor Losmapimod (Los)-loaded and ROS scavenger Tempo (Tem)-conjugated cationic polypeptide micelles, designated as MTem/Los) for safe and efficient DED management. Cationic MTem/Los improve ocular retention of conjugated water-soluble Tem and loaded water-insoluble Los via electrostatic interaction with negatively charged mucin on the cornea, enabling an increase in therapeutic efficiency and a decrease in dosing frequency. Mechanistically, MTem/Los effectively decrease ROS over-production, reduce the expression of proinflammatory cytokines and chemokines, restrain macrophage proinflammatory phenotypic transformation, and inhibit cell apoptosis. Therapeutically, the dual-functional MTem/Los suppress the inflammatory response, reverse corneal epithelial defect, save goblet cell dysfunction, and recover tear secretion, thus breaking the vicious cycle and alleviating the DED. Moreover, MTem/Los exhibit excellent biocompatibility and tolerability for potential application as a simple and rapid treatment of oxidative stress- and inflammation-induced disorders, including DED.

Polycatechol-Derived Mesoporous Polydopamine Nanoparticles for Combined ROS Scavenging and Gene Interference Therapy in Inflammatory Bowel Disease

Benefiting from the evolution of nanotechnology, the combination therapy by gene interference and reactive oxygen species (ROS) scavenging are expected, which holds great potential in inflammatory bowel disease (IBD) therapy. However, the functional integration of different therapeutic modules through interface modification of gene vectors for safe and efficient treatment is urgently needed. Herein, we present a catechol chemistry-mediated core-shell nanoplatform for ROS scavenging-mediated oxidative stress alleviation and siRNA-mediated gene interference in a dextran sulfate sodium (DSS)-induced colitis model. The nanoplatform is constructed by employing mesoporous polydopamine nanoparticles (MPDA NPs) with surface modification of amines as the porous core for TNF-α-siRNA loading (31 wt %) and exerts an antioxidant function, while PDA-induced biomineralization of the calcium phosphate (CaP) coating is used as the pH-sensitive protective shell to prevent siRNA from premature release. The CaP layer degraded under weakly acidic subcellular conditions (lysosomes); thus, the synergistic integration of catechol and cation moieties on the exposed surface of MPDA resulted in an efficient lysosomal escape. Subsequently, effective ROS scavenging caused by the electron-donating ability of MPDA and efficient knocking down (40.5%) of tumor necrosis factor-α (TNF-α) via sufficient cytosolic gene delivery resulted in a synergistic anti-inflammation therapeutic effect both in vitro and in vivo. This work establishes the first paradigm of synergistic therapy in IBD by ROS scavenging and gene interference.

Interactions between Nanoparticles and Intestine

The use of nanoparticles (NPs) has surely grown in recent years due to their versatility, with a spectrum of applications that range from nanomedicine to the food industry. Recent research focuses on the development of NPs for the oral administration route rather than the intravenous one, placing the interactions between NPs and the intestine at the centre of the attention. This allows the NPs functionalization to exploit the different characteristics of the digestive tract, such as the different pH, the intestinal mucus layer, or the intestinal absorption capacity. On the other hand, these same characteristics can represent a problem for their complexity, also considering the potential interactions with the food matrix or the microbiota. This review intends to give a comprehensive look into three main branches of NPs delivery through the oral route: the functionalization of NPs drug carriers for systemic targets, with the case of insulin carriers as an example; NPs for the delivery of drugs locally active in the intestine, for the treatment of inflammatory bowel diseases and colon cancer; finally, the potential concerns and side effects of the accidental and uncontrolled exposure to NPs employed as food additives, with focus on E171 (titanium dioxide) and E174 (silver NPs).