Stimulation-responsive mucoadhesive probiotics for inflammatory bowel disease treatment by scavenging reactive oxygen species and regulating gut microbiota

Evaluating the anti-inflammatory and antioxidant efficacy of complementary and alternative medicines (CAM) used for management of inflammatory bowel disease: a comprehensive review

Inflammatory bowel disease (IBD) is a chronic autoimmune condition whose pathogenesis has not been fully elucidated, and current treatments are not definitive and often carry several side effects. The Complementary and Alternative Medicine (CAM) offers a new approach to conventional medicine. However, their clinical application and mechanisms remain limited.Objective: The aim of this review is to evaluate the anti-inflammatory, impact on microbiota and antioxidant efficacy of currently available CAM for IBD.Methods: The literature collection was obtained from Google Scholar, MEDLINE, PubMed and Web of Science (WOS). Studies in both human and animal models, published in English language between 2018 and 2024, were selected. Sixty-seven studies were included in the current review after inclusion and exclusion screening processes.Results: Mostly, studies showed significant anti-inflammatory, gut microbiota restoring, antioxidant effects of polyphenols, polysaccharides, emodin, short-chain fatty acids (SCFA; including butyrate, propionate and acetate), and probiotics although some contrasting results were noted. Current evidence shows that polyphenols exhibit the most consistent result in alleviating IBD pathophysiology, primarily due to their significant SCFA-elevating effect.Discussion: Future studies may focus on human studies, narrowing down on individual factors which may change natural product's metabolism. Further research studies are also essential to obtain therapeutic recommendations.

Metal ion coordinated tea polyphenol nanocoating for enhanced probiotic therapy in inflammatory bowel disease

Probiotics encapsulated with metal-phenolic networks (MPNs) present a promising approach for treating inflammatory bowel diseases (IBD). However, current MPN systems predominantly use tannic acid (TA) as the phenolic source, with limited exploration of other polyphenols, and face challenges in long-term stability and biocompatibility. Herein, three alternative tea polyphenols, gallic acid (GA), epigallocatechin (EGC) and epigallocatechin gallate (EGCG), were coordinated with ferric ions, to fabricate MPN-coated Lactobacillus rhamnosus LGG (MPN@L). These were compared with TA-based MPN@L to evaluate their effectiveness in alleviating IBD. All MPN@L complexes demonstrated superior adhesion and retention compared to uncoated probiotics in both ex vivo and in vivo models. Specifically, EGC@L exhibited the highest survival rate throughout gastrointestinal digestion, with a 2.7 log CFU/mL improvement over uncoated probiotics, and showed optimal retention in murine intestine with a fluorescence intensity of 24.3 × 106 p/s/cm2/sr by day four. All MPN@L formation effectively alleviated ulcerative colitis by reducing myeloperoxidase levels, modulating cytokines profiles, and enhancing gut microbiota. EGC@L particularly increased beneficial bacterial genera, including Lactobacillus, Adlercreutzia, and Oscillospira, while decreasing the pro-inflammatory genera. This study highlights the potential of MPN-based probiotic microencapsulation to enhanced treatment for gastrointestinal disorders, expending the application of probiotic microencapsulation in IBD therapy.

Surface-functionalized bacteria: Frontier explorations in next-generation live biotherapeutics

Screening robust living bacteria to produce living biotherapeutic products (LBPs) represents a burgeoning research field in biomedical applications. Despite their natural abilities to colonize bio-interfaces and proliferate, harnessing bacteria for such applications is hindered by considerable challenges in unsatisfied functionalities and safety concerns. Leveraging the high degree of customization and adaptability on the surface of bacteria demonstrates significant potential to improve therapeutic outcomes and achieve tailored functionalities of LBPs. This review focuses on the recent laboratory strategies of bacterial surface functionalization, which aims to address these challenges and potentiate the therapeutic effects in biomedicine. Firstly, we introduce various functional materials that are used for bacterial surface functionalization involving organic, inorganic, and biological materials. Secondly, the methodologies for achieving bacterial surface functionalization are categorized into three primary approaches including covalent bonding, non-covalent interactions, and hybrid techniques, while various advantages and limitations of different modification strategies are compared from multiple perspectives. Subsequently, the current status of the applications of surface-functionalized bacteria in bioimaging and disease treatments, especially in the treatment of inflammatory bowel disease (IBD) and cancer is summarized. Finally, challenges and pressing issues in the development of surface-functionalized bacteria as LBPs are presented.

Engineered probiotics remodel the intestinal epithelial barrier and enhance bacteriotherapy for inflammatory bowel diseases

Inflammatory bowel diseases (IBDs) are often associated with compromised epithelial barriers and dysregulated gut microbiota. In this study, we revealed the synergistic effect that zinc and indole-3-carbinol (I3C) have in restoring the epithelial barrier, and co-localized them on a ZI platform, which was further conjugated to the surface of Escherichia coli Nissle 1917 (EcN). The ZI@EcN formulation effectively delivered ZI to colon tissues and extended its retention in the intestines due to the colonic colonization effect of EcN, thereby promoting the sustained release of zinc and I3C for optimal synergistic effects on epithelial barrier remodeling. The restored epithelium acts as a protective barrier, preventing the infiltration of toxins and pathogens, which significantly reduces inflammation in colonic tissues. Additionally, EcN enriched the gut microbiome, increasing the abundance of beneficial bacteria while reducing that of pathogens, demonstrating its significant efficacy in gut microbiome regulation. In dextran sulfate sodium-induced mouse colitis models, ZI@EcN exhibited substantially improved prophylactic and therapeutic efficacy with favorable safety profiles, highlighting its potential for clinical applications. STATEMENT OF SIGNIFICANCE: This study highlighted the synergistic effects that zinc and indole-3-carbinol, both derived from dietary sources, have on restoring integrity of the intestinal epithelial barrier. A platform (ZI@EcN) was also developed for the targeted delivery and sustained release of zinc and indole-3-carbinol, specifically in colonic tissues, for colitis treatment. This platform not only restores the compromised intestinal epithelial barrier but also regulates the dysbiotic gut microbiota, promoting the recovery of a healthy intestinal microenvironment and showing promise in alleviating complex symptoms in a single formulation. Furthermore, the formulation demonstrated potent prophylactic and therapeutic efficacy against colitis, with favorable safety profiles, and a strong potential for clinical applications.

Microfluidics-Based Microcarriers for Live-Cell Delivery

Live-cell therapy has emerged as a revolutionary treatment modality, providing a novel therapeutic avenue for intractable diseases. However, a major challenge in live-cell therapy is to maintain live-cell viability and efficacy during the treatment. Microcarriers are crucial for enhancing cell retention, viability, and functions by providing a protective scaffold and creating a supportive environment for live-cell proliferation and metabolism. For microcarrier construction, the microfluidic technology demonstrates excellent characteristics in terms of controllability over microcarrier size and morphology as well as potential for high-throughput production. To date, multiple live-cell delivery microcarrier types (e.g., microspheres, microfibers, and microneedles) are prepared via microfluidic liquid templates to meet different therapeutic needs. In this review, recent developments in microfluidics-based microcarriers for live-cell delivery are presented. It is focused on categorizing the structural design of microfluidic-derived cell-laden microcarriers, and summarizing various therapeutic applications. Finally, an outlook is provided on the future challenges and opportunities in this field.

Multifunctional Double-Loaded Oral Nanoplatform for Computed Tomography Imaging-Guided and Integrated Treatment of Inflammatory Bowel Disease

Excessive reactive oxygen species, disruption of the epithelial barrier, immune dysregulation, and gut microbiota imbalance are key factors driving the onset of inflammatory bowel disease (IBD) and complicating its treatment. Prompt diagnosis of diseases and precise delivery of therapeutic agents to inflamed intestinal sites offer promising targeted strategies for effectively treating IBD. Here, a barium sulfate-based nanoplatform (BaSO4@PDA@CeO2/DSP, BPCD) for synergistic delivery of nanozymes and drugs was developed. With enhanced colonic retention after oral drug delivery, this nanoplatform enables precise and effective targeting of inflammatory sites and CT imaging guidance to address multiple factors contributing to IBD. A comprehensive therapeutic effect was achieved through the synergistic action of cerium oxide with the optimized Ce3+/Ce4+ ratio and sustained release of dexamethasone sodium phosphate. Benefiting from superior gastrointestinal stability, the nanoplatform is highly effective in treating IBD by alleviating oxidative stress, modulating macrophage polarization balance, gut flora composition, and repairing the epithelial barrier. BPCD inhibits the development of IBD through multiple mechanisms and has superior biocompatibility, emerging as a practical alternative to traditional IBD therapies.

Probiotic Membrane-Modified Nanocomposite Alleviates Inflammation and Microbiota Dysbiosis in Colitis by Scavenging Oxidative Stress and Restoring Immune Homeostasis

Inflammatory bowel disease (IBD) is a complex chronic intestinal disorder in which excessive oxidative stress, dysregulated immune response, and microbiota dysbiosis contribute to recurrent episodes of inflammation in the colonic mucosa. Current clinical treatments focusing solely on inflammation resolution often exhibit limited efficacy due to the inability to fundamentally improve the pathological microenvironment. Herein, a probiotic membrane-modified drug delivery nanocomposite, namely, MPDA@Cur@EM, is developed for the comprehensive treatment of IBD. It contains two components: the curcumin-loaded mesoporous polydopamine nanoparticle (MPDA@Cur) as the core and the Escherichia coli Nissle 1917 outer membrane (EM) as the surface. For MPDA@Cur, the pathological microenvironment triggers the responsive release of curcumin. Importantly, MPDA@Cur can effectively alleviate the inflammatory response of LPS-activated macrophages through MPDA-mediated ROS scavenging and curcumin-induced M2 polarization. In the dextran sulfate sodium (DSS)-induced colitis model, the EM coating not only allows for the targeting enrichment of orally administered MPDA@Cur@EM to the inflamed colonic mucosa, but also participates in the regulation of intestinal flora. Consequently, MPDA@Cur@EM efficiently attenuates the inflammatory reaction and restores the intestinal barrier functions, demonstrated by the multipronged manner of restoring redox balance, remodeling immune homeostasis, and reshaping the gut microecology. Collectively, this work provides a safe and promising codelivery strategy of probiotic product, antioxidative nanoenzyme, and therapeutic drug for comprehensive management of IBD.

Multi-functionalized probiotics through layer-by-layer coating with tannic acid-Mg2+ and casein phosphopeptide complexes for preventing ulcerative colitis

Gut microbiota imbalance-induced inflammatory response and oxidative stress are two of the main reasons causing ulcerative colitis (UC). Probiotics show potent modulating effects on microbiota imbalance and have been considered as an optimal substitute of antibiotics for preventing UC. However, the harsh environment of the gastrointestinal tract is not conducive to the survival and persistence of probiotics. Herein, we developed an efficient surface coating strategy to overcome the delivery challenges of probiotics and also endow them with multiple functions through layer-by-layer coating with tannic acid (TA)-Mg2+ and casein phosphopeptide (CPP) complexes. Saccharomyces boulardii (SB), one of yeasts that have been widely applied in the food and pharmaceutical field, was used as a model probiotic for assessing the synergistic effects of this coating strategy on preventing UC. Multi-functionalized probiotic thus prepared (called SB@TA-Mg2+@CPP) had significantly enhanced stability under the simulated gastric and intestinal fluid conditions, and also displayed vigorous cell viability and potent antioxidant activity. In the mouse model of dextran sulfate sodium (DSS)-induced colitis, SB@TA-Mg2+@CPP exhibited strong antioxidant and anti-inflammatory effects, remarkably increased the abundance and diversity of gut microbiota, and maintained gut barrier integrity. Meanwhile, SB@TA-Mg2+@CPP notably improved the adsorption of Mg2+, which also contributed to enhance the preventive effect against DSS-induced colitis. In summary, this study provides an efficient coating strategy to develop multi-functionalized probiotics for preventing UC.

Probiotic Delivery for Editing of the Gut Microbiota to Mitigate Colitis and Maintain Hepatic Homeostasis Via Gut-Liver Axis

Inflammatory bowel disease (IBD) compromises the intestinal barrier and disrupts gut microbiota, impacting liver function via the gut-liver axis, which in turn influences the intestinal microbiota through lipid metabolites exacerbating IBD. This study introduced a probiotic-based treatment using Lactobacillus acidophilus encapsulated in tungsten ion-loaded mesoporous polydopamine (LA@WMPDA) to ameliorate colitis and balance enterohepatic homeostasis. After oral administration, the encapsulation could protect Lactobacillus acidophilus, scavenge reactive oxygen/nitrogen species, and the released tungsten ions would inhibit abnormal Enterobacteriaceae growth during colitis, consequently restoring the intestinal barrier and regulating the gut microbiota. Nontargeted metabolomics and transcriptomics analyses showed increased short-chain fatty acids and indole derivatives, and decreased hepatic lipid metabolism. Pathways associated with immune response, cell migration and death, and response to bacterium showed significant down-regulation in the colon and liver transcriptome analysis. Thus, this study provided a pioneered paradigm for IBD treatment and highlighted the regulation of liver-related metabolic functions via the gut-liver axis.

Probiotic nanocomposite materials with excellent resistance, inflammatory targeting, and multiple efficacies for enhanced treatment of colitis in mice

The occurrence of inflammatory bowel disease (IBD) is relevant to impaired intestinal mucosal barrier and disordered gut microbiota, subsequently leading to excessive production of reactive oxygen species (ROS) and elevated levels of inflammatory factors. Traditional therapies focus on inhibiting inflammation, but the vast majority involve non-targeted systemic administration, whose long-term use may result in potential side effects. Oral microbial therapy has exhibited great application prospects currently in IBD treatment; however, its progress has been slowed by issues with deficient bioavailability, poor targeting of colitis, and low therapeutic efficacy. Consequently, it is exceedingly desirable to develop a strategy by which probiotics can be endowed with additional anti-inflammatory and antioxidant properties, as well as enhanced targeting of the inflamed intestine. Herein, we present an innovative therapeutic strategy for encapsulating probiotic Bacillus coagulans spores with rosmarinic acid (RA) and silk fibroin (SF). Probiotics in spore morphology possessed strong gastrointestinal environmental resistance; RA alleviated oxidative damage by scavenging ROS and inhibited inflammatory responses; SF assisted probiotics release and colonize in the inflamed intestine. We demonstrated the therapeutic efficacy of probiotic composite materials in a colitis mouse model, which significantly alleviated a series of colitis symptoms, inhibited inflammatory cytokine storms, restored the balance of the gut microbiota, and downregulated inflammation-related signaling pathways. We are optimistic that the utilization of therapeutic nanocoating to modify probiotics will open up novel avenues for future microbial therapy targeting IBD.

Versatile inulin/trans-ferulic acid/silk sericin nanoparticles-nourished probiotic complex with prolonged intestinal retention for synergistic therapy of inflammatory bowel disease

To achieve effective long-term synergistic treatment of inflammatory bowel disease (IBD) with probiotics, we developed a versatile inulin/trans-ferulic acid/silk sericin nanoparticles-nourished probiotic complex. Inulin/TFA/SS nanoparticles were fabricated by inulin, trans-ferulic acid (TFA), and silk sericin (SS), and then loaded onto the surface of poly-l-lysine (PLL) and poly-glutamic acid (PGA)-coated Bifidobacterium longum (BL) to obtain BL@PLL-PGA-Inulin/TFA/SS NPs (BL@PP-NPs). This design simultaneously endowed the complex with excellent gastrointestinal resistance, antioxidant, and anti-inflammation abilities. Moreover, the inulin in the nanoparticles acts as a prebiotic, promoting the Bifidobacterium's rapid proliferation to exert effects within a short period. Compared with uncoated BL, BL@PP-NPs exhibited excellent gastric acid tolerance and up to 31.32-fold colonic colonization, and the ROS scavenging and proliferative capacity were increased by 5.61- and 1.39-fold, respectively. In a mouse model of dextran sulfate sodium (DSS)- and trinitrobenzene sulfonic acid (TNBS)-induced colitis, the components of Inulin/TFA/SS NPs synergized with probiotics to efficiently treat IBD by attenuating oxidative stress, decreasing inflammation, repairing intestinal barrier, and promoting the rapid proliferation of probiotics to reverse gut microbial disorders. Collectively, food-grade BL@PP-NPs represent a novel approach to probiotic modification that offers an effective, safe, and synergistic therapy for IBD.

Microbiota governs host chenodeoxycholic acid glucuronidation to ameliorate bile acid disorder induced diarrhea

BACKGROUND

Disorder in bile acid (BA) metabolism is known to be an important factor contributing to diarrhea. However, the pathogenesis of BA disorder-induced diarrhea remains unclear.

METHODS

The colonic BA pool and microbiota between health piglets and BA disorder-induced diarrheal piglets were compared. Fecal microbiota transplantation and various cell experiments further indicated that chenodeoxycholic acid (CDCA) metabolic disorder produced CDCA-3β-glucuronide, which is the main cause of BA disorder diarrhea. Non-targeted metabolomics uncovered the inhibition of the BA glucuronidation by Lactobacillus reuteri (L. reuteri) is through deriving indole-3-carbinol (I3C). In vitro, important gene involved in the reduction of BA disorder induced-diarrhea were screened by RNA transcriptomics sequencing, and activation pathway of FXR-SIRT1-LKB1 to alleviate BA disorder diarrhea and P53-mediated apoptosis were proposed in vitro by multifarious siRNA interference, CO-IP, immunofluorescence, and so on, which mechanism was also verified in a variety of mouse models.

RESULTS

Here, we reveal for the first time that core microbiota derived I3C represses gut epithelium glucuronidation, particularly 3β-glucuronic CDCA production, which reaction is mediated by host UDP glucuronosyltransferase family 1 member A4 (UGT1A4) and necessary of BA disorder induced diarrhea. Mechanistically, L. reuteri derived I3C activates aryl hydrocarbon receptor to decrease UGT1A4 transcription and CDCA-3β-glucuronide content, thereby upregulating FXR-SIRT1-LKB1 signal. LKB1 binds with P53 based on protein interaction, ultimately resists to apoptosis and diarrhea. Moreover, I3C assists CDCA to attain the ameliorative effects of FXR activation in BA disorder diarrhea, through reversion of abnormal metabolism pathway, improving the outcomes of CDCA supplement.

CONCLUSION

These findings uncover the crucial interplay between gut epithelial cells and microbes, highlighting UGT1A4-mediated conversion of CDCA-3β-glucuronide as a key target for ameliorating BA disorder-induced diarrhea. Video Abstract.

Lactobacillus fermentum 016 Alleviates Mice Colitis by Modulating Oxidative Stress, Gut Microbiota, and Microbial Metabolism

Ulcerative colitis (UC) is a chronic and progressive inflammatory gastrointestinal disease closely associated with gut microbiota dysbiosis and metabolic homeostasis disruption. Although targeted microbial therapies are an emerging intervention strategy for inflammatory bowel disease (IBD), the mechanisms by which specific probiotics, such as Lactobacillus fermentum 016 (LF), alleviate UC remain unclear. The current study evaluated the effects of LF supplementation on gut health in a basal model using C57BL/6 mice. Subsequently, the preventive effects and mechanisms of LF supplementation on DSS-induced UC were systematically investigated. According to our findings, LF supplementation revealed immunoregulatory capabilities with significantly altered gut the composition of microbiota and metabolic activities, particularly enhancing tryptophan metabolism. In the UC model, LF supplementation effectively mitigated weight loss, increased the disease activity index (DAI), and alleviated diarrhea, rectal bleeding, and colon shortening. Moreover, it reduced colonic pathological damage and histological injury scores. LF intervention improved antioxidant markers and intestinal mucosal barrier function with the activation of the Nrf2-Keap1 signaling pathway and regulation of systemic inflammatory markers, i.e., IL-1β, IL-6, TNF-α, IFN-γ, IL-4, and IL-10. Importantly, LF supplementation reversed metabolic disturbances by significantly increasing the abundance of beneficial genera (e.g., g_Dubosiella, g_Faecalibaculum, g_Odoribacter, g_Candidatus_saccharimonas, g_Roseburia, and g_Eubacterium_xylanophilum_group) and elevating tryptophan metabolites (e.g., melatonin, kynurenic acid, 3-indoleacetic acid, 5-methoxytryptophan, and 5-hydroxyindoleacetic acid). In conclusion, Lactobacillus fermentum 016 exhibits potential for regulating gut microbiota homeostasis, enhancing tryptophan metabolism, and alleviating UC, providing critical insights for developing probiotic-based precision therapeutic strategies for IBD.

Cyanobacteria-probiotics symbionts for modulation of intestinal inflammation and microbiome dysregulation in colitis

Inflammatory bowel disease (IBD) is often associated with excessive inflammatory response and highly dysregulated gut microbiota. Traditional treatments utilize drugs to manage inflammation, potentially with probiotic therapy as an adjuvant. However, current standard practices often suffer from detrimental side effects, low bioavailability, and unsatisfactory therapeutic outcomes. Microbial complexes characterized by mutually beneficial symbiosis hold great promise for IBD therapy. Here, we aggregated Synechocystis sp. PCC6803 (Sp) with Bacillus subtilis (BS) by biomimetic mineralization to form cyanobacteria-probiotics symbionts (ASp@BS), which reshaped a healthy immune system and gut microbiota in a murine model of acute colitis. The symbionts exhibited excellent tolerance to the harsh environment of the gastrointestinal tract. Importantly, probiotics within the symbionts created a local anaerobic environment to activate the [NiFe]-hydrogenase enzyme of cyanobacteria, facilitating the production of hydrogen gas (H2) to persistently scavenge elevated reactive oxygen species and alleviate inflammatory factors. The resulting reduced inflammation improves the viability of the probiotics to efficiently regulate the gut microbiota and reshape the intestinal barrier functions. Our research elucidates that ASp@BS leverages the synergistic interaction between Sp and BS to create a therapeutic platform that addresses multiple aspects of IBD, offering a promising and comprehensive solution for IBD treatment.

From probiotic chassis to modification strategies, control and improvement of genetically engineered probiotics for inflammatory bowel disease

With the rising morbidity of inflammatory bowel disease (IBD) year by year, conventional therapeutic drugs with systemic side effects are no longer able to meet the requirements of patients. Probiotics can improve gut microbiota, enhance intestinal barrier function, and regulate mucosal immunity, making them a potential complementary or alternative therapy for IBD. To compensate for the low potency of probiotics, genetic engineering technology has been widely used to improve their therapeutic function. In this review, we systematically summarize the genetically engineered probiotics used for IBD treatment, including probiotic chassis, genetic modification strategies, methods for controlling probiotics, and means of improving efficacy. Finally, we provide prospects on how genetically engineered probiotics can be extended to clinical applications.

Mutual adhesion of Lactobacillus spp. to intestinal cells: A review of perspectives on surface layer proteins and cell surface receptors

The bacterial ability to adhere and colonize in the gut is a key prerequisite to become a probiotic. Lactobacillus spp. surface layer proteins (SLPs) play an important role for such functions in the human body. Interestingly, all SLPs in spite of their structural variation promote adhesion and colonization. A clear understanding about the binding sites of SLPs with the host and their binding modes would help to precisely reveal the process of Lactobacillus spp.-host interaction. Therefore, in this paper, we have sorted out the Lactobacillus spp. SLPs and their adhesion sites in human intestinal cells. Such SLPs included surface layer protein, motif proteins, binding proteins and moonlighting proteins, while enterocyte adhesion receptors included transmembrane glycoproteins and extracellular matrix proteins. We also summarized the tools to assess the adhesion by Lactobacillus spp. Finally, we recommended that three-dimensional cell models and intestinal microarrays could be major tools for assessing adhesion in the future.

Tyrosinase-Woven Melanin Nets for Melanoma Therapy through Targeted Mitochondrial Tethering and Enhanced Photothermal Treatment

Manipulating intracellular biological processes and organelles has emerged as a pivotal strategy to influence cellular physiological functions. Mitochondria, recognized as the powerhouse of cells, play a crucial role in tumorigenesis and progression. Inspired by the Nature's tyrosinase-catalyzed melanin formation within melanoma cells, here an approach is developed using a polysaccharide dually-functionalized with tyrosine and triphenylphosphine (TPP) for targeted mitochondria cross-linking in melanoma cells. This technique intricately weaves melanin nets within the cells, serving as a tether for the mitochondria and effectively decelerating tumor metabolism through nanoparticle-net transformation. Tyrosinase acts as the "needle", while the functionalized polysaccharide serves as the "string" successfully constructing nets within the cell. Furthermore, the tyrosinase-catalyzed cross-linking of tyrosine not only facilitates the production of artificial melanin but also enhances the photothermal conversion efficiency of melanoma cells, leading to decrease of the tumor growth. This study unveils a non-drug method for regulating organelle physiological activity and introduces photothermal treatment. This work not only sheds light on the manipulation of cellular functions but also holds promise for advancing cancer therapeutic strategies.

Microenvironment-responsive nano-bioconjugated vesicles for the multi-pronged treatment of liver fibrosis

Liver fibrosis represents an inevitable stage of various chronic liver diseases. The activated hepatic stellate cells (aHSCs) are the main drivers for promoting the development of liver fibrosis. Meanwhile, liver macrophages can secrete pro-inflammatory cytokines, thus accelerating the deterioration of the liver. Regulating both aHSCs and the inflammatory microenvironment in the liver simultaneously may be an effective strategy for treating liver fibrosis. A multi-pronged nano-bioconjugated system, HNP-B-aEV, was developed according to the above strategy. Based on cell aggregate-derived extracellular vesicles (aEVs) and hydroxychloroquine (HCQ)-loaded nanoparticles (HNP) modified with retinol, HNP-B-aEV is prepared via a reactive oxygen species (ROS)-responsive boronate linker. In the ROS-rich microenvironment of liver fibrosis, aEVs and HNP are released, eliminating ROS, and targeting aHSCs and macrophages respectively to inhibit the activation of HSCs. Both in vitro and in vivo studies demonstrated that HNP-B-aEV can significantly inhibit the release of inflammatory factors from M1 macrophages, remodeling the microenvironment and preventing the activation of HSCs, offering a multi-pronged treatment for liver fibrosis. This strategy can inhibit the progression of liver fibrosis at its source, providing a new perspective for the clinical treatment of liver fibrosis.

Hyaluronic Acid Receptor-Mediated Nanomedicines and Targeted Therapy

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

Targeted Modulation of Redox and Immune Homeostasis in Acute Lung Injury Using a Thioether-Functionalized Dendrimer

Acute lung injury (ALI) is the pathophysiological precursor of acute respiratory distress syndrome. It is characterized by increased oxidative stress and exaggerated inflammatory response that disrupts redox reactions and immune homeostasis in the lungs, thereby posing significant clinical challenges. In this study, an internally functionalized thioether-enriched dendrimer Sr-G4-PEG is developed, to scavenge both proinflammatory cytokines and reactive oxygen species (ROS) and restore homeostasis during ALI treatment. The dendrimers are synthesized using an efficient and orthogonal thiol-ene "click" chemistry approach that involves incorporating thioether moieties within the dendritic architectures to neutralize the ROS. The ROS scavenging of Sr-G4-PEG manifests in its capacity to sequester proinflammatory cytokines. The synergistic effects of scavenging ROS and sequestering inflammatory cytokines by Sr-G4-PEG contribute to redox remodeling and immune homeostasis, along with the modulation of the NLRP3-pyroptosis pathway. Treatment with Sr-G4-PEG enhances the therapeutic efficacy of ALIs by alleviating alveolar bleeding, reducing inflammatory cell infiltration, and suppressing the release of inflammatory cytokines. These results suggest that Sr-G4-PEG is a potent nanotechnological candidate for remodeling redox and immune homeostasis in the treatment of ALIs, demonstrating the great potential of dendrimer-based nanomedicine for the treatment of respiratory pathologies.

Gastrointestinal Self-Adaptive and Nutrient Self-Sufficient Akkermansia muciniphila-Gelatin Porous Microgels for Synergistic Therapy of Ulcerative Colitis

To realize effective and long-term synergistic therapy of ulcerative colitis (UC) with probiotics, we developed gastrointestinal self-adaptive and nutrient self-sufficient Akkermansia muciniphila (AKK)-gelatin porous microgels (AKK@GPMGs). In AKK@GPMGs, AKK was covered with sequential layers of proanthocyanidins (PAs), mucin (MUC), and phosphatidylcholine (PC) to obtain AKK@PAs-MUC-PC (AKK@PMP), and then encapsulated within the methacrylate-modified gelatin porous microgels. AKK@GPMGs provide sufficient mucus as a nutrition source for AKK and boost resistance to stomach acid by 30.49-fold, and colonization in the intestines is enhanced by 83.46 times. The microgels can be dissociated by matrix metalloproteinase at the inflammatory sites of the intestine, and release AKK@PMP, which acts as "band-aid" that adheres to the inflamed colon for a long time and offers improved synergistic therapy for UC. Compared to uncoated AKK, AKK@GPMGs increase reactive oxygen species scavenging capacity by 26.47 times, improve the intestinal mucus layer thickness by 5.63 times, increase the goblet cells abundance by 3.93 times, reduce intestinal permeability by 5.60 times and significantly enhance beneficial gut microbiota while repressing harmful microbiota. These results indicate that AKK@GPMGs can restore mucus layer and tight junction integrity, reduce inflammation and oxidative stress, and regulate gut microbiota homeostasis to effectively treat intestinal inflammation.

Single-cell encapsulation systems for probiotic delivery: Armor probiotics

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

Gastrodin Alleviates DSS-Induced Colitis in Mice through Strengthening Intestinal Barrier and Modulating Gut Microbiota

Inflammatory bowel diseases (IBDs) are commonly associated with dysfunctional intestinal barriers and disturbed gut microbiota. Gastrodin, a major bioactive ingredient of Gastrodia elata Blume, has been shown to exhibit anti-oxidation and anti-inflammation properties and could mitigate non-alcoholic fatty liver disease, but its role in modulating IBD remains elusive. The aim of this study was to investigate the impact of gastrodin on DSS-induced colitis in mice and explore its potential mechanisms. Gastrodin supplementation alleviated clinical symptoms such as weight loss, a shortened colon, and a high disease activity index. Meanwhile, gastrodin strengthened the intestinal barrier by increasing the 0expression of tight junction proteins and mucin. Furthermore, Gastrodin significantly reduced pro-inflammatory cytokine secretion in mice by downregulating the NF-κB and MAPK pathways. Gut microbiota analysis showed that gastrodin improved the DSS-disrupted microbiota of mice. These findings demonstrate that gastrodin could attenuate DSS-induced colitis by enhancing the intestinal barrier and modulating the gut microbiota, providing support for the development of a gastrodin-based strategy to prevent or combat IBD.

Bacillus siamensis Targeted Screening from Highly Colitis-Resistant Pigs Can Alleviate Ulcerative Colitis in Mice

Ulcerative colitis (UC) is often accompanied by intestinal inflammation and disruption of intestinal epithelial structures, which are closely associated with changes in the intestinal microbiota. We previously revealed that Min pigs, a native Chinese breed, are more resistant to dextran sulfate sodium (DSS)-induced colitis than commercial Yorkshire pigs. Characterizing the microbiota in Min pigs would allow identification of the core microbes that confer colitis resistance. By analyzing the microbiota linked to the disease course in Min and Yorkshire pigs, we observed that Bacillus spp. were enriched in Min pigs and positively correlated with pathogen resistance. Using targeted screening, we identified and validated Bacillus siamensis MZ16 from Min pigs as a bacterial species with biofilm formation ability, superior salt and pH tolerance, and antimicrobial characteristics. Subsequently, we administered B. siamensis MZ16 to conventional or microbiota-deficient BALB/c mice with DSS-induced colitis to assess its efficacy in alleviating colitis. B. siamensis MZ16 partially counteracted DSS-induced colitis in conventional mice, but it did not mitigate DSS-induced colitis in microbiota-deficient mice. Further analysis revealed that B. siamensis MZ16 administration improved intestinal ecology and integrity and immunological barrier function in mice. Compared to the DSS-treated mice, mice preadministered B. siamensis MZ16 exhibited improved relative abundance of potentially beneficial microbes (Lactobacillus, Bacillus, Christensenellaceae R7, Ruminococcus, Clostridium, and Eubacterium), reduced relative abundance of pathogenic microbes (Escherichia-Shigella), and maintained colonic OCLN and ZO-1 levels and IgA and SIgA levels. Furthermore, B. siamensis MZ16 reduced proinflammatory cytokine levels by reversing NF-κB and MAPK pathway activation in the DSS group. Overall, B. siamensis MZ16 from Min pigs had beneficial effects on a colitis mouse model by enhancing intestinal barrier functions and reducing inflammation in a gut microbiota-dependent manner.

Orally administrated liquid metal agents for inflammation-targeted alleviation of inflammatory bowel diseases

Rapid drug clearance and off-target effects of therapeutic drugs can induce low bioavailability and systemic side effects and gravely restrict the therapeutic effects of inflammatory bowel diseases (IBDs). Here, we propose an amplifying targeting strategy based on orally administered gallium (Ga)-based liquid metal (LM) nano-agents to efficiently eliminate reactive oxygen and nitrogen species (RONS) and modulate the dysregulated microbiome for remission of IBDs. Taking advantage of the favorable adhesive activity and coordination ability of polyphenol structure, epigallocatechin gallate (EGCG) is applied to encapsulate LM to construct the formulations (LM-EGCG). After adhering to the inflamed tissue, EGCG not only eliminates RONS but also captures the dissociated Ga to form EGCG-Ga complexes for enhancive accumulation. The detained composites protect the intestinal barrier and modulate gut microbiota for restoring the disordered enteral microenvironment, thereby relieving IBDs. Unexpectedly, LM-EGCG markedly decreases the Escherichia_Shigella populations while augmenting the abundance of Akkermansia and Bifidobacterium, resulting in favorable therapeutic effects against the dextran sulfate sodium-induced colitis.

2D Is Better: Engineering Polydopamine into Cationic Nanosheets to Enhance Anti-Inflammatory Capability

Polydopamine nanomaterials have emerged as one of the most popular organic materials for the management of oxidative stress-mediated inflammatory diseases. However, their current anti-inflammatory ability is still unsatisfactory because of limited phenolic hydroxyl groups, and oxidation reaction-medicated reactive oxygen and nitrogen species (RONS) scavenging. Herein, via fusing dimension engineering and surface charge engineering, 2D cationic polydopamine nanosheets (PDA NSs) capable of scavenging multiple danger signals to enhance anti-inflammatory capability are reported. Compared with conventional spherical polydopamine nanoparticles, 2D PDA NSs exhibit three- to fourfold enhancement in RONS scavenging capability, which should be attributed to high specific surface area and abundant phenol groups of 2D ultrathin structure. To further enhance the anti-inflammatory ability, polylysine molecules are absorbed on the surface of PDA NSs to endow the scavenging capability of cell-free DNA (cfDNA), another typical inflammatory factor to exacerbate the pathogenesis of inflammation. Molecular mechanisms reveal that cationic PDA NSs can concurrently activate Keap1-Nrf2 and block TLR9 signaling pathway, achieving synergistical inflammation inhibition. As a proof of concept, cationic PDA NSs with RONS and cfDNA dual-scavenging capability effectively alleviate the inflammatory bowel disease in both delayed and prophylactic models, much better than the clinical drug 5-aminosalicylic acid.

Melanin Nanoparticle-Modified Probiotics for Targeted Synergistic Therapy of Ulcerative Colitis

Ulcerative colitis (UC) is a recurrent chronic mucosal inflammation disease whose most significant pathological characteristics are intestinal inflammation and damaged mucosal barrier induced by reactive oxygen/nitrogen species, abnormal immune microenvironment, and intestinal microecological imbalance. Oral probiotics are a living therapy for intestinal diseases, but their clinical application is hindered by poor bacterial biological activity and insufficient intestinal retention. Here, we developed a targeted oral formulation, functionalized probiotic Lf@MPB, with Lactobacillus fermentum (Lf) as the core and modified melanin nanoparticles (MNPs) on its surface through a click reaction of tricarboxyphenylboronic acid for synergistic therapy of UC. In vitro experiments showed that Lf@MPB not only possessed strong free radical scavenging ability, reduced cellular mitochondrial polarization, and inhibited apoptosis but also significantly enhanced the viability of Lf probiotics in simulated gastrointestinal fluid. Fluorescence imaging in vivo revealed the high accumulation of Lf@MPB at the site of intestinal inflammation in dextran sulfate sodium-induced UC mice. Moreover, in vivo results demonstrated that Lf@MPB effectively alleviated oxidative stress and inflammatory response and restored the intestinal barrier. In addition, 16S rRNA gene sequencing verified that Lf@MPB could increase the abundance and diversity of intestinal microbial communities and optimize microbial composition to inhibit the progression of UC. This work combines effective antioxidant and anti-inflammatory strategies with the oral administration of functionalized probiotics to provide a promising alternative for UC treatment.

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.

Construction of Fu brick tea polysaccharide-cold plasma modified alginate microgels for probiotic delivery: Enhancing viability and colonization

Emerging food processing technologies provide broader avenues for enhancing probiotic delivery systems. In this study, the new Fu brick tea polysaccharide (FBTP) was extracted and combined with cold plasma-modified alginate nano-montmorillonite (AMT) to prepare microgels by ionic gelation to improve the viability of encapsulated Lactobacillus kefiranofaciens JKSP109. Results showed that cold plasma treatment for 3 min changed the surface charge of AMT biopolymer solution, and FBTP addition reduced the particle size to the lowest of 223 ± 5.50 nm. Morphological analysis showed that the AMT treated with cold plasma for 3 min and FBTP (C3AMT + FBTP) formed a dense microgel through electrostatic interaction, and the probiotics were randomly distributed in their internal polysaccharide network, as well as the interlayer and surrounding of nanoparticles. The probiotics immobilized in C3AMT + FBTP microgel exhibited the highest viability (8.48 ± 0.03 log CFU/g) and colonic colonization after exposure to simulated gastrointestinal conditions. In addition, the good antioxidant activity of FBTP reduced the loss of probiotic viability during storage, with only 2.58 log CFU/g decreased after 4 weeks. Therefore, such probiotic products enriched with natural bioactive ingredients can be developed as a potential functional food additive.

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.