Development of Spleen Targeting H2S Donor Loaded Liposome for the Effective Systemic Immunomodulation and Treatment of Inflammatory Bowel Disease

Acid-resistant chemotactic DNA micromotors for probiotic delivery in inflammatory bowel disease

Microcapsules composed of synthetic polymeric matrices have attracted considerable attention in delivering oral probiotics. However, existing polymeric microcapsules demonstrate inadequate acid resistance and adaptability, as well as deficiency in the inflamed colon-specificity and uncontrolled release of probiotics therein. Herein, a DNA microcapsule is prepared as a probiotic-transporting micromotor through photo-crosslinking of hyaluronic acid methacrylate and acrydite-modified A-/C-rich oligomers within the microfludically generated droplets in the presence of nitric oxide-cleavable crosslinker and gas donor manganese carbonyl (MnCO). As the microcapsules traverse stomach, duodenum, and ultimately colon, the formation and dissociation of A-motif and i-motif structures instigate a reversible shrinking-swelling transition of microcapsules to preserve probiotic viability. Subsequently, the microcapsules exhibit chemotaxis towards inflamed colon site, driven by a gas-generating reaction between MnCO and elevated reactive oxygen species. Following disintegration of the microcapsules, triggered by endogenous nitric oxide, probiotics are released to reshape the dysbiosis of intestinal microflora. This advanced delivery system offers significant promise for the effective clinical management of inflammatory bowel disease.

Chemotaxis-driven hybrid liposomes recover intestinal homeostasis for targeted colitis therapy

Inflammatory bowel disease (IBD) is closely linked to the dysregulation of intestinal homeostasis, accompanied by intestinal epithelial barrier destruction, dysbiosis of gut microbiota, subsequent inflammatory factor infiltration, and excessive oxidative stress. Conventional therapeutics focus on suppressing inflammation and often suffer from metabolic instability as well as limited targeting, thereby leading to suboptimal remission rates and severe side effects. Here, we designed bacterial outer membrane vesicle (OMV, from Stenotrophomonas maltophilia)-fused and borneol-modified liposomes (BO/OMV-lipo@LU) for targeted delivery of luteolin to recover intestinal homeostasis by alleviating inflammation and modulating dysregulated intestinal epithelial barrier, redox balance, and gut microbiota in IBD. In a Caco-2/HT29-MTX monolayer model, the OMV and borneol-bifunctionalized liposomes enhanced the uptake efficiency of unfunctionalized liposomes with a 2-fold increase. Owing to the chemotaxis-driven colon-targeting ability of OMVs and the ability of borneol to promote intestinal epithelial uptake, the hybrid liposomes successfully targeted the inflamed colon. In a colitis mouse model, BO/OMV-lipo@LU exhibited enhanced efficacy following oral administration. The BO/OMV-lipo@LU treatment increased the colon length and body weights of mice suffering colitis by 40 % and 15 %, respectively, with values comparable to the healthy control group. Notably, BO/OMV-lipo@LU alleviated proinflammatory markers, modulated redox balance, and restored the intestinal epithelial barrier. In addition, the formulation increased the abundance of beneficial microbiota while decreasing the abundance of harmful microbiota. These results demonstrated that this biomimetic nanoplatform could be exploited as a safe and effective gut-targeted delivery system in IBD treatment.

Anti-Inflammatory Effects of Hydrogen Sulfide in Axes Between Gut and Other Organs

Significance: Hydrogen sulfide (H2S), a ubiquitous small gaseous signaling molecule, plays a critical role in various diseases, such as inflammatory bowel disease (IBD), rheumatoid arthritis (RA), ischemic stroke, and myocardial infarction (MI) via reducing inflammation, inhibiting oxidative stress, and cell apoptosis. Recent Advances: Uncontrolled inflammation is closely related to pathological process of ischemic stroke, RA, MI, and IBD. Solid evidence has revealed the axes between gut and other organs like joint, brain, and heart, and indicated that H2S-mediated anti-inflammatory effect against IBD, RA, MI, and ischemic stroke might be related to regulating the functions of axes between gut and other organs. Critical Issues: We reviewed endogenous H2S biogenesis and the H2S-releasing donors, and revealed the anti-inflammatory effects of H2S in IBD, ischemic stroke, RA, and MI. Importantly, this review outlined the potential role of H2S in the gut-joint axis, gut-brain axis, and gut-heart axis as a gasotransmitter. Future Direction: The rate, location, and timing of H2S release from its donors determine its potential success or failure as a useful therapeutic agent and should be focused on in the future research. Therefore, there is still a need to explore internal and external sources monitoring and controlling H2S concentration. Moreover, more efficient H2S-releasing compounds are needed; a better understanding of their chemistry and properties should be further developed. Antioxid. Redox Signal. 42, 341-360.

Orally Deliverable Iron-Ceria Nanotablets for Treatment of Inflammatory Bowel Disease

Ceria-based nanoparticles are versatile in treating various inflammatory diseases, but their feasibility in clinical translation is undermined by safety concerns and a limited delivery system. Meanwhile, the idiopathic nature of inflammatory bowel disease (IBD) calls for a wider variety of therapeutics via moderation of the intestinal immune system. In this regard, the synthesis and oral formulation of iron-ceria nanoparticles (CF NPs) with enhanced nanozymic activity and lower toxicity risk than conventional ceria-based nanoparticles are reported. CF NPs are clustered in calcium phosphate (CaP) and coated with a pH-responsive polymer to provide the enteric formulation of iron-ceria nanotablets (CFNT). CFNT exhibits a marked alleviative efficacy in the dextran sodium sulfate (DSS)-induced enterocolitis model in vivo by modulating the pro-inflammatory behavior of innate immune cells including macrophages and neutrophils, promoting anti-inflammatory cytokine profiles, and downregulating key transcription factors of inflammatory pathways.

In Situ Slow-Release Hydrogen Sulfide Therapeutics for Advanced Disease Treatments

Hydrogen sulfide (H2S) gas therapygarners significant attention for its potential to improve outcomes in various disease treatments. The quantitative control of H2S release is crucial for effective the rapeutic interventions; however, traditional researchon H2S therapy frequently utilizes static release models and neglects the dynamic nature of blood flow. In this study, we propose a novel slow-release in-situ H2S release model that leverages the dynamic hydrolysis of H2S donorswithin the bloodstream. Calcium sulfide nanoparticles (CaS NPs) withmicrosolubility characteristics exhibit continuous H2S release, surpassing 24 h at normal blood flow velocities. The extended-release profile demonstrates superior potential in aligning with the bell-shapedpharmacological effect of H2S, compared to NaHS. Moreover, we synthesisedrare earth-doped CaS NPs (CaS: Eu2+, Sm3+ NPs) tha texhibit persistent luminescence, enabling visualisation of the continuous H2S release in trials. Our results demonstrate that lowdose CaS: Eu2+, Sm3+ NPs significantly reduces seizureduration to 1.2 ± 0.7 minutes, while high dose effectively suppresses colontumor growth with a tumor inhibition rate of 54%. Remarkably, these findings closely resemble endogenous H2S levels in treating epilepsy and tumors. This innovative slow-release, in-situ H2S the rapeutic approach via hydrolysis rejuvenates the development of H2S-basedtherapeutics.

Yeast-Inspired Orally-Administered Nanocomposite Scavenges Oxidative Stress and Restores Gut Immune Homeostasis for Inflammatory Bowel Disease Treatment

Excessive oxidative stress, dysregulated immune homeostasis, and disruption of the intestinal epithelial barrier are crucial features of inflammatory bowel disease (IBD). Traditional treatments focusing solely on inflammation resolution remain unsatisfactory. Herein, a yeast-inspired orally administered nanocomposite was developed. First, the MD@MPDA core was fabricated by integrating manganese dioxide (MnO2) nanozymes onto diallyl trisulfide (H2S prodrug)-loaded mesoporous polydopamine nanoparticles (MPDA). Then, yeast cell wall (YCW) was chosen to encapsulate MD@MPDA, namely, YMD@MPDA. The β-glucan embedded in the YCW shell not only protected the nanocomposite from the harsh gastrointestinal environment but also allowed the targeting enrichment in the inflamed colon. Furthermore, M1 macrophages triggered the intracellular GSH-responsive H2S release in the pathological microenvironment. MD@MPDA effectively alleviated inflammatory responses by MnO2-mediated ROS-scavenging and H2S-participated immunomodulation. The synergistic action contributed to macrophage mitochondrial function restoration and M2 polarization by suppressing NOX4 signaling and p38 MAPK pro-inflammatory signaling. In the mice model of dextran sulfate sodium (DSS)-induced IBD, the multipronged manner of scavenging oxidative stress, remodeling innate and adaptive immune homeostasis, and reshaping gut microbiota caused by YMD@MPDA effectively ameliorated inflammation and restored intestinal barrier functions. Overall, the YMD@MPDA nanocomposite provides a promising codelivery strategy of antioxidative nanozymes and gas prodrugs for the comprehensive management of IBD.

Folic acid-based hydrogels co-assembled with protocatechuic acid for enhanced treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) presents a significant therapeutic challenge due to the need for oral drug delivery systems that withstand acidic environment of stomach while effectively targeting intestinal inflammation. To address this issue, we created a novel hydrogel system based on a folic acid (FA)-dopamine (DA) conjugate, co-assembled with protocatechuic acid (PCA), to form F-DP hydrogels. These hydrogels demonstrated robust anti-gastric acid, mucosal adhesive, and injectable properties, enhancing their efficacy for targeted delivery. In DSS-induced colitis mouse models, treatment with F-DP hydrogels resulted in significant therapeutic improvements, including increased body weight, reduced disease activity index (DAI), and maintained colon length. Biochemical assays revealed that F-DP hydrogels significantly enhanced antioxidant enzyme activities (GSH and SOD) and reduced oxidative stress markers (NO and MDA). Histological assessments confirmed effective repair of the colonic mucosal barrier, restoration of tight junction protein ZO-1, and reduction of inflammatory lesions. Furthermore, immunofluorescence staining indicated that F-DP hydrogels facilitated macrophages polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, thereby reducing inflammation and promoting tissue repair. Our study demonstrates that F-DP hydrogels show significant potential for improving IBD treatment through enhanced gastric resistance, intestinal adhesion, and synergistic anti-inflammatory effects, warranting further investigation for clinical applications.

Oxidative stress disrupts vascular microenvironmental homeostasis affecting the development of atherosclerosis

Atherosclerosis is primarily an inflammatory reaction of the cardiovascular system caused by endothelial damage, leading to progressive thickening and hardening of the vessel walls, as well as extensive necrosis and fibrosis of the surrounding tissues, the most necessary pathological process causing cardiovascular disease. When the body responds to harmful internal and external stimuli, excess oxygen free radicals are produced causing oxidative stress to occur in cells and tissues. Simultaneously, the activation of inflammatory immunological processes is followed by an elevation in oxygen free radicals, which directly initiates the release of cytokines and chemokines, resulting in a detrimental cycle of vascular homeostasis abnormalities. Oxidative stress contributes to the harm inflicted upon vascular endothelial cells and the decrease in nitric oxide levels. Nitric oxide is crucial for maintaining vascular homeostasis and is implicated in the development of atherosclerosis. This study examines the influence of oxidative stress on the formation of atherosclerosis, which is facilitated by the vascular milieu. It also provides an overview of the pertinent targets and pharmaceutical approaches for treating this condition.

Sequential Release of Ibuprofen and the Gasotransmitter Hydrogen sulfide using Oxanorbornane-Based Synthetic Lipids as Carriers

After understanding the biological signaling roles of hydrogen sulfide and its involvement in various physiological processes, there has been enormous interest in exploring its therapeutic utility in areas such as cancer, inflammation, cardiovascular diseases, etc. There is also growing interest in using suitable H2S donors in combination with other drugs to improve the treatment outcome through the modulation of multiple pathways. The premature release of H2S from small molecule donors and the difficulty in controlling its spatio-temporal distribution are the major challenges during these efforts. Hence the development of appropriate carriers that can release this gasotransmitter along with the therapeutic entity of interest in a controlled manner has high significance. In this regard, this report presents a novel drug delivery system from oxanorbornane-based synthetic lipids that carries a H2S-releasing 1,2-dithiole-3-thione moiety as part of the head group. Nanoaggregates of the resulting conjugate are not only capable of efficiently entrapping a non-steroidal anti-inflammatory drug such as ibuprofen, but also release this drug and H2S in a controlled and sequential manner.

Erythroid progenitor cell modulates cancer immunity: Insights and implications

The emergence of immunotherapies such as immune checkpoint blockade (ICB) has markedly enhanced cancer treatment outcomes for numerous patients. Nevertheless, the effectiveness of immunotherapy demonstrates substantial variation across different cancer types and individual patients. The immunosuppressive characteristics of the tumor microenvironment (TME) play a crucial role in contributing to this variation. Typically, people focus on cells with immunosuppressive functions in the TME, such as tumor-associated macrophages (TAMs), but research on TAMs alone cannot fully explain the complex structure and composition of the TME. Recent studies have reported that tumors can induce erythroid progenitor cells (EPCs) to exert immunosuppressive functions, not only acting within the TME but also secreting artemin in the spleen to promote tumor progression. In this review, we summarize the recent research on EPCs and tumors in recent years. We elucidate the mechanisms by which EPCs exert immunosuppressive functions in tumor-bearing conditions. In this review, we further propose potential therapeutic strategies targeting EPCs and emphasize the importance of in-depth exploration of the mechanisms by which EPCs regulate tumors and the immune system, as well as the significant clinical value of developing corresponding drugs.

Nanotechnology-Mediated Immunomodulation Strategy for Inflammation Resolution

Inflammation serves as a common characteristic across a wide range of diseases and plays a vital role in maintaining homeostasis. Inflammation can lead to tissue damage and the onset of inflammatory diseases. Although significant progress is made in anti-inflammation in recent years, the current clinical approaches mainly rely on the systemic administration of corticosteroids and antibiotics, which only provide short-term relief. Recently, immunomodulatory approaches have emerged as promising strategies for facilitating the resolution of inflammation. Especially, the advanced nanosystems with unique biocompatibility and multifunctionality have provided an ideal platform for immunomodulation. In this review, the pathophysiology of inflammation and current therapeutic strategies are summarized. It is mainly focused on the nanomedicines that modulate the inflammatory signaling pathways, inflammatory cells, oxidative stress, and inflammation targeting. Finally, the challenges and opportunities of nanomaterials in addressing inflammation are also discussed. The nanotechnology-mediated immunomodulation will open a new treatment strategy for inflammation therapy.

Lymphoid organ-targeted nanomaterials for immunomodulation of cancer, inflammation, and beyond

Nanomaterials exhibit significant potential for stimulating immune responses, offering both local and systemic modulation across a variety of diseases. The lymphoid organs, such as the spleen and lymph nodes, are home to various immune cells, including monocytes and dendritic cells, which contribute to both the progression and prevention/treatment of diseases. Consequently, many nanomaterial formulations are being rationally designed to target these organs and engage with specific cell types, thereby inducing therapeutic and protective effects. In this review, we explore crucial cellular interactions and processes involved in immune regulation and highlight innovative nano-based immunomodulatory approaches. We outline essential considerations in nanomaterial design with an emphasis on their impact on biological interactions, targeting capabilities, and treatment efficacy. Through selected examples, we illustrate the strategic targeting of therapeutically active nanomaterials to lymphoid organs and the subsequent immunomodulation for infection resistance, inflammation suppression, self-antigen tolerance, and cancer immunotherapy. Additionally, we address current challenges, discuss emerging topics, and share our outlook on future developments in the field.

Nanoparticle-Based Drug Delivery Systems for Inflammatory Bowel Disease Treatment

Inflammatory bowel disease (IBD) is a chronic, non-specific inflammatory condition characterized by recurring inflammation of the intestinal mucosa. However, the existing IBD treatments are ineffective and have serious side effects. The etiology of IBD is multifactorial and encompasses immune, genetic, environmental, dietary, and microbial factors. The nanoparticles (NPs) developed based on specific targeting methodologies exhibit great potential as nanotechnology advances. Nanoparticles are defined as particles between 1 and 100 nm in size. Depending on their size and surface functionality, NPs exhibit different properties. A variety of nanoparticle types have been employed as drug carriers for the treatment of inflammatory bowel disease (IBD), with encouraging outcomes observed in experimental models. They increase the bioavailability of drugs and enable targeted drug delivery, promoting localized treatment and thus enhancing efficacy. Nevertheless, numerous challenges persist in the translation from nanomedicine to clinical application, including enhanced formulations and preparation techniques, enhanced drug safety profiles, and so forth. In the future, it will be necessary for scientists and clinicians to collaborate in order to study disease mechanisms, develop new drug delivery strategies, and screen new nanomedicines. Nevertheless, numerous challenges persist in the translation from nanomedicine to clinical application, including enhanced formulations and preparation techniques, enhanced drug safety profiles, and so forth. In the future, it will be necessary for scientists and clinicians to collaborate in order to study disease mechanisms, develop new drug delivery strategies, and screen new nanomedicines.

Development of Indocyanine Green/Methyl-β-cyclodextrin Complex-Loaded Liposomes for Enhanced Photothermal Cancer Therapy

Photothermal therapy (PTT) is a promising cancer therapeutic approach due to its spatial selectivity and high potency. Indocyanine green (ICG) has been considered a biocompatible PTT agent. However, ICG has several challenges to hinder its clinical use including rapid blood clearance and instability to heat, light, and solvent, leading to a loss of photoactivation property and PTT efficacy. Herein, we leveraged stabilizing components, methyl-β-cyclodextrin and liposomes, in one nanoplatform (ICD lipo) to enhance ICG stability and the photothermal therapeutic effect against cancer. Compared to ICG, ICD lipo displayed a 4.8-fold reduction in degradation in PBS solvent after 30 days and a 3.4-fold reduction in photobleaching after near-infrared laser irradiation. Moreover, in tumor-bearing mice, ICD lipo presented a 2.7-fold increase in tumor targetability and inhibited tumor growth 9.6 times more effectively than did ICG without any serious toxicity. We believe that ICD lipo could be a potential PTT agent for cancer therapeutics.

Alleviating Pyroptosis of Intestinal Epithelial Cells to Restore Mucosal Integrity in Ulcerative Colitis by Targeting Delivery of 4-Octyl-Itaconate

Current therapies primarily targeting inflammation often fail to address the root relationship between intestinal mucosal integrity and the resulting dysregulated cell death and ensuing inflammation in ulcerative colitis (UC). First, UC tissues from human and mice models in this article both emphasize the crucial role of Gasdermin E (GSDME)-mediated pyroptosis in intestinal epithelial cells (IECs) as it contributes to colitis by releasing proinflammatory cytokines, thereby compromising the intestinal barrier. Then, 4-octyl-itaconate (4-OI), exhibiting potential for anti-inflammatory activity in inhibiting pyroptosis, was encapsulated by butyrate-modified liposome (4-OI/BLipo) to target delivery for IECs. In brief, 4-OI/BLipo exhibited preferential accumulation in inflamed colonic epithelium, attributed to over 95% of butyrate being produced and absorbed in the colon. As expected, epithelium barriers were restored significantly by alleviating GSDME-mediated pyroptosis in colitis. Accordingly, the permeability of IECs was restored, and the resulting inflammation, mucosal epithelium, and balance of gut flora were reprogrammed, which offers a hopeful approach to the effective management of UC.

Bioinspired and bioderived nanomedicine for inflammatory bowel disease

Due to its chronic nature and complex pathophysiology, inflammatory bowel disease (IBD) poses significant challenges for treatment. The long-term therapies for patients, often diagnosed between the ages of 20 and 40, call for innovative strategies to target inflammation, minimize systemic drug exposure, and improve patients' therapeutic outcomes. Among the plethora of strategies currently pursued, bioinspired and bioderived nano-based formulations have garnered interest for their safety and versatility in the management of IBD. Bioinspired nanomedicine can host and deliver not only small drug molecules but also biotherapeutics, be made gastroresistant and mucoadhesive or mucopenetrating and, for these reasons, are largely investigated for oral administration, while surprisingly less for rectal delivery, recommended first-line treatment approach for several IBD patients. The use of bioderived nanocarriers, mostly extracellular vesicles (EVs), endowed with unique homing abilities, is still in its infancy with respect to the arsenal of nanomedicine under investigation for IBD treatment. An emerging source of EVs suited for oral administration is ingesta, that is, plants or milk, thanks to their remarkable ability to resist the harsh environment of the upper gastrointestinal tract. Inspired by the unparalleled properties of natural biomaterials, sophisticated avenues for enhancing therapeutic efficacy and advancing precision medicine approaches in IBD care are taking shape, although bottlenecks arising either from the complexity of the nanomedicine designed or from the lack of a clear regulatory pathway still hinder a smooth and efficient translation to the clinics. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Inflammatory bowel disease and rheumatoid arthritis share a common genetic structure

Background

The comorbidity rate of inflammatory bowel disease (IBD) and rheumatoid arthritis (RA) is high; nevertheless, the reasons behind this high rate remain unclear. Their similar genetic makeup probably contributes to this comorbidity.

Methods

Based on data obtained from the genome-wide association study of IBD and RA, we first assessed an overall genetic association by performing the linkage disequilibrium score regression (LDSC) analysis. Further, a local correlation analysis was performed by estimating the heritability in summary statistics. Next, the causality between the two diseases was analyzed by two-sample Mendelian randomization (MR). A genetic overlap was analyzed by the conditional/conjoint false discovery rate (cond/conjFDR) method.LDSC with specific expression of gene analysis was performed to identify related tissues between the two diseases. Finally, GWAS multi-trait analysis (MTAG) was also carried out.

Results

IBD and RA are correlated at the genomic level, both overall and locally. The MR results suggested that IBD induced RA. We identified 20 shared loci between IBD and RA on the basis of a conjFDR of <0.01. Additionally, we identified two tissues, namely spleen and small intestine terminal ileum, which were commonly associated with both IBD and RA.

Conclusion

Herein, we proved the presence of a polygenic overlap between the genetic makeup of IBD and RA and provided new insights into the genetic architecture and mechanisms underlying the high comorbidity between these two diseases.

Multicomponent Synthesis of Imidazole-Based Ionizable Lipids for Highly Efficient and Spleen-Selective Messenger RNA Delivery

The spleen emerges as a pivotal target for mRNA delivery, prompting a continual quest for specialized and efficient lipid nanoparticles (LNPs) designed to enhance spleen-selective transfection efficiency. Here we report imidazole-containing ionizable lipids (IMILs) that demonstrate a pronounced preference for mRNA delivery into the spleen with exceptional transfection efficiency. We optimized IMIL structures by constructing and screening a multidimensional IMIL library containing multiple heads, tails, and linkers to perform a structure-activity correlation analysis. Following high-throughput in vivo screening, we identified A3B7C2 as a top-performing IMIL in spleen-specific mRNA delivery via the formulated LNPs, achieving a remarkable 98% proportion of splenic transfection. Moreover, A3B7C2-based LNPs are particularly potent in splenic dendritic cell transfection. Comparative analyses revealed that A3B7C2-based LNPs achieved a notable 2.8-fold and 12.9-fold increase in splenic mRNA transfection compared to SM102 and DLin-MC3-DMA lipid formulations, respectively. Additionally, our approach yielded an 18.3-fold enhancement in splenic mRNA expression compared to the SORT method without introducing additional anionic lipids. Collectively, these IMILs highlight promising avenues for further research in spleen-selective mRNA delivery. This work offers valuable insights for the swift discovery and rational design of ionizable lipid candidates tailored for spleen-selective transfection, thereby facilitating the application of mRNA therapeutics in spleen-related interventions.

A fluorescent probe for detecting H2O2 and delivering H2S in lysosomes and its application in maintaining the redox environments

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) that can be used as a marker for the occurrence of oxidative stress in the organism. Lysosomes serve as intracellular digestive sites, and when the concentration of H2O2 in them is abnormal, lysosomal function is often impaired, leading to the development of diseases. Hydrogen sulfide (H2S) acts as a gaseous signaling molecule that scavenges H2O2 from cells and tissues, thereby maintaining the redox environment of the body. However, most of the reported hydrogen peroxide fluorescent probes so far can only detect H2O2, but cannot maintain the intracellular redox environment. In this paper, an H2O2 fluorescent probe LN-HOD with lysosomal targeting properties was designed and synthesized by combining the H2O2 recognition site with a naphthylamine fluorophore via a thiocarbamate moiety. The probe has the advantages of large Stokes shift (110 nm), high sensitivity and good H2S release capability. The probe LN-HOD can be used to detect H2O2 in cells, zebrafish and plant roots. In addition, LN-HOD detects changes in the concentration of H2O2 in plant roots when Arabidopsis is stressed by cadmium ion (Cd2+). And through its ability to release H2S, it can help to remove excess H2O2 and maintain the redox environment in cells, zebrafish and plant roots. The present work provides new ideas for the detection and assisted removal of H2O2, which contributes to the in-depth study of the cellular microenvironment in organisms.

Spleen-targeted delivery systems and strategies for spleen-related diseases

The spleen, body's largest secondary lymphoid organ, is also a vital hematopoietic and immunological organ. It is regarded as one of the most significant organs in humans. As more researchers recognize the functions of the spleen, clinical methods for treating splenic diseases and spleen-targeted drug delivery systems to improve the efficacy of spleen-related therapies have gradually developed. Many modification strategies (size, charge, ligand, protein corona) and hitchhiking strategies (erythrocytes, neutrophils) of nanoparticles (NPs) have shown a significant increase in spleen targeting efficiency. However, most of the targeted drug therapy strategies for the spleen are to enhance or inhibit the immune function of the spleen to achieve therapeutic effects, and there are few studies on spleen-related diseases. In this review, we not only provide a detailed summary of the design rules for spleen-targeted drug delivery systems in recent years, but also introduce common spleen diseases (splenic tumors, splenic injuries, and splenomegaly) with the hopes of generating more ideas for future spleen research.

Inhibiting the cGAS-STING Pathway in Ulcerative Colitis with Programmable Micelles

Ulcerative colitis is a chronic condition in which a dysregulated immune response contributes to the acute intestinal inflammation of the colon. Current clinical therapies often exhibit limited efficacy and undesirable side effects. Here, programmable nanomicelles were designed for colitis treatment and loaded with RU.521, an inhibitor of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. STING-inhibiting micelles (SIMs) comprise hyaluronic acid-stearic acid conjugates and include a reactive oxygen species (ROS)-responsive thioketal linker. SIMs were designed to selectively accumulate at the site of inflammation and trigger drug release in the presence of ROS. Our in vitro studies in macrophages and in vivo studies in a murine model of colitis demonstrated that SIMs leverage HA-CD44 binding to target sites of inflammation. Oral delivery of SIMs to mice in both preventive and delayed therapeutic models ameliorated colitis's severity by reducing STING expression, suppressing the secretion of proinflammatory cytokines, enabling bodyweight recovery, protecting mice from colon shortening, and restoring colonic epithelium. In vivo end points combined with metabolomics identified key metabolites with a therapeutic role in reducing intestinal and mucosal inflammation. Our findings highlight the significance of programmable delivery platforms that downregulate inflammatory pathways at the intestinal mucosa for managing inflammatory bowel diseases.

Effect of bovine colostrum liposomes on the bioavailability of immunoglobulin G and their immunoregulatory function in immunosuppressed BALB/c mice

Bovine colostrum (BC) has high nutritional value; however, the low bioavailability of immune active substances in BC may affect their immunoregulatory function. Our previous studies indicated that encapsulating bovine colostrum with liposomes could enable the sustained release of immunoglobulin G in vitro; however, the effect of bovine colostrum liposomes (BCLs) on the bioavailability of immunoglobulins in vivo is still unknown. In addition, the immunoregulatory function of BCLs on immunosuppressed mice is still unclear. Therefore, our current study aimed to explore the effect of BCLs on the bioavailability of immunoglobulins, and further explore their immunoregulatory effect on immunosuppressed BALB/c mice. Through metabolic cage experiments, it was shown that BCLs decreased the urine and fecal concentrations of IgG and exhibited a higher bioavailability of IgG in mice than BC (about 2-fold). In addition, by establishing an immunosuppressed animal model, it was found that BCLs could increase the body weight, spleen weight, and thymus weight in immunosuppressed BALB/c mice, which further restored the serum levels of interleukin-4 (IL-4), interleukin-10 (IL-10), tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ). Through histology analysis, it was suggested that BCLs restored the structure of jejunal epithelial cells, which was accompanied by an improvement in intestinal cytokine levels (IL-4, IL-10, TNF-α, and IFN-γ). Finally, BCLs increased serum and intestine concentrations of immunoglobulin G (IgG) and immunoglobulin A (IgA) in immunosuppressed BALB/c mice, which further indicated that BCLs had a sustained-release effect for immunoglobulin G in vivo. Our current research will provide a basis for understanding the role of BCLs on the bioavailability of IgG and their immunoregulatory effect on immunosuppressed mice, which might further provide some reference for the application of BCLs.

A H2 S-Generated Supramolecular Photosensitizer for Enhanced Photodynamic Antibacterial Infection and Relieving Inflammation

Photodynamic therapy (PDT) is a promising treatment against bacteria-caused infections. By producing large amounts of reactive oxygen species (ROS), PDT can effectively eliminate pathogenic bacteria, without causing drug resistance. However, excessive ROS may also impose an oxidative stress on surrounding tissues, resulting in local inflammation. To avoid this major drawback and limit pro-inflammation during PDT, this work prepared a supramolecular photosensitizer (TPP-CN/CP5) based on host-guest interactions between a cysteine-responsive cyano-tetraphenylporphyrin (TPP-CN) and a water-soluble carboxylatopillar[5]arene (CP5). TPP-CN/CP5 not only possesses excellent photodynamic antibacterial properties, but also shows good anti-inflammatory and cell protection capabilities. Under 660 nm light irradiation, TPP-CN/CP5 could rapidly produce abundant ROS for sterilization. After the PDT process, the addition of cysteine (Cys) triggers the release of H2 S from TPP-CN. H2 S then stops the induced inflammation by inhibiting the production of related inflammatory factors. Both in vitro and in vivo experiments show the excellent antibacterial effects and anti-inflammatory abilities of TPP-CN/CP5. These results will certainly promote the clinical application of PDT in the treatment of bacterial infectious diseases.

Advancements in hydrogel-based drug delivery systems for the treatment of inflammatory bowel disease: a review

Inflammatory bowel disease (IBD) is a chronic disorder that affects millions of individuals worldwide. However, current drug therapies for IBD are plagued by significant side effects, low efficacy, and poor patient compliance. Consequently, there is an urgent need for novel therapeutic approaches to alleviate IBD. Hydrogels, three-dimensional networks of hydrophilic polymers with the ability to swell and retain water, have emerged as promising materials for drug delivery in the treatment of IBD due to their biocompatibility, tunability, and responsiveness to various stimuli. In this review, we summarize recent advancements in hydrogel-based drug delivery systems for the treatment of IBD. We first identify three pathophysiological alterations that need to be addressed in the current treatment of IBD: damage to the intestinal mucosal barrier, dysbiosis of intestinal flora, and activation of inflammatory signaling pathways leading to disequilibrium within the intestines. Subsequently, we discuss in depth the processes required to prepare hydrogel drug delivery systems, from the selection of hydrogel materials, types of drugs to be loaded, methods of drug loading and drug release mechanisms to key points in the preparation of hydrogel drug delivery systems. Additionally, we highlight the progress and impact of the hydrogel-based drug delivery system in IBD treatment through regulation of physical barrier immune responses, promotion of mucosal repair, and improvement of gut microbiota. In conclusion, we analyze the challenges of hydrogel-based drug delivery systems in clinical applications for IBD treatment, and propose potential solutions from our perspective.

Evidence for the gut-skin axis: Common genetic structures in inflammatory bowel disease and psoriasis

BACKGROUND

Inflammatory bowel disease (IBD) and psoriasis (Ps) are common immune-mediated diseases that exhibit clinical comorbidity, possibly due to a common genetic structure. However, the exact mechanism remains unknown.

METHODS

The study population consisted of IBD and Ps genome-wide association study (GWAS) data. Genetic correlations were first evaluated. Then, the overall evaluation employed LD score regression (LDSC), while the local assessment utilized heritability estimation from summary statistics (HESS). Causality assessment was conducted through two-sample Mendelian randomization (2SMR), and genetic overlap analysis utilized the conditional false discovery rate/conjunctional FDR (cond/conjFDR) method. Finally, LDSC applied to specifically expressed genes (LDSC-SEG) was performed at the tissue level. For IBD and Ps-specific expressed genes, genetic correlation, causality, shared genetics, and trait-specific associated tissues were methodically examined.

RESULTS

At the genomic level, both overall and local genetic correlations were found between IBD and Ps. MR analysis indicated a positive causal relationship between Ps and IBD. The conjFDR analysis with a threshold of < 0.01 identified 43 loci shared between IBD and Ps. Subsequent investigations into disease-associated tissues indicated a close association of IBD and Ps with whole blood, lung, spleen, and EBV-transformed lymphocytes.

CONCLUSION

The current research offers a novel perspective on the association between IBD and Ps. It contributes to an enhanced comprehension of the genetic structure and mechanisms of comorbidities in both diseases.

Size-Dependent In Vivo Transport of Nanoparticles: Implications for Delivery, Targeting, and Clearance

Understanding the in vivo transport of nanoparticles provides guidelines for designing nanomedicines with higher efficacy and fewer side effects. Among many factors, the size of nanoparticles plays a key role in controlling their in vivo transport behaviors due to the existence of various physiological size thresholds within the body and size-dependent nano-bio interactions. Encouraged by the evolving discoveries of nanoparticle-size-dependent biological effects, we believe that it is necessary to systematically summarize the size-scaling laws of nanoparticle transport in vivo. In this review, we summarized the size effect of nanoparticles on their in vivo transport along their journey in the body: begin with the administration of nanoparticles via different delivery routes, followed by the targeting of nanoparticles to intended tissues including tumors and other organs, and eventually clearance of nanoparticles through the liver or kidneys. We outlined the tools for investigating the in vivo transport of nanoparticles as well. Finally, we discussed how we may leverage the size-dependent transport to tackle some of the key challenges in nanomedicine translation and also raised important size-related questions that remain to be answered in the future.

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.

H2S-Reactivating Antitumor Immune Response after Microwave Thermal Therapy for Long-Term Tumor Suppression

Microwave thermal therapy (MWTT) is one of the most potent ablative treatments known, with advantages like deep penetration, minimal invasion, repeatable operation, and low interference from bone and gas. However, microwave (MW) is not selective against tumors, and residual tumors after incomplete ablation will generate immunosuppression, ultimately making tumors prone to recurrence and metastasis. Herein, a nano-immunomodulator (Bi-MOF-l-Cys@PEG@HA, BMCPH) is proposed to reverse the immunosuppression and reactivate the antitumor immune effect through responsively releasing H2S in tumor cells for improving MWTT. Under MW irradiation, BMCPH will mediate MWTT to ablate tumors and release l-cysteine (l-Cys) to react with the highly expressed cystathionine β-synthase in tumor to generate H2S. The generated H2S can inhibit the accumulation of myeloid-derived suppressor cells (MDSCs) and promote the expression of cytotoxic T lymphocytes (CTLs). Moreover, Bi-MOF can also scavenge reactive oxygen species (ROS), a major means of MDSCs-mediated immunosuppression, to further weaken the immunosuppressive effect. Simultaneously, the surface-covered HA will gather CTLs around the tumor to enhance the immune response. This nano gas immunomodulator provides an idea for the sensitive and tunable release of unstable gas molecules at tumor sites. The strategy of H2S gas to reverse immunosuppression and reactivate antitumor immune response introduces a direction to reduce the risk of tumor recurrence and metastasis after thermal ablation.

Anti-Inflammatory Effects of Dietary Polyphenols through Inhibitory Activity against Metalloproteinases

Matrix metalloproteinases (MMPs) are zinc-dependent metalloproteinases that play important roles in a variety of diseases, including cancer, cardiovascular disease, diabetes, obesity, and brain diseases. Dietary polyphenols are thought to have a variety of beneficial effects on these diseases characterized by inflammation. Clinical studies have demonstrated that MMPs are in most cases upregulated in various inflammatory diseases, including osteoarthritis, rheumatoid arthritis, inflammatory bowel disease, and Alzheimer's disease. Studies using patient-derived human samples, animal studies, and cellular experiments have suggested that polyphenols may be beneficial against inflammatory diseases by suppressing MMP gene expression and enzyme activity. One important mechanism by which polyphenols exert their activity is the downregulation of reactive oxygen species that promote MMP expression. Another important mechanism is the direct binding of polyphenols to MMPs and their inhibition of enzyme activity. Molecular docking analyses have provided a structural basis for the interaction between polyphenols and MMPs and will help to explore new polyphenol-based drugs with anti-inflammatory properties.