ROS-responsive nanoparticles for oral delivery of luteolin and targeted therapy of ulcerative colitis by regulating pathological microenvironment

Copper-luteolin nanocomplexes for Mediating multifaceted regulation of oxidative stress, intestinal barrier, and gut microbiota in inflammatory bowel disease

Oxidative stress, dysbiosis, and immune dysregulation have been confirmed to play pivotal roles in the complex pathogenesis of inflammatory bowel disease (IBD). Herein, we design copper ion-luteolin nanocomplexes (CuL NCs) through a metal-polyphenol coordination strategy, which plays a multifaceted role in the amelioration of IBD. The fabricated CuL NCs function as therapeutic agents with exceptional antioxidant and anti-inflammatory capabilities because of their great stability and capacity to scavenge reactive oxygen species (ROS). It can effectively modulate the inflammatory microenvironment including facilitating the efficient reduction of pro-inflammatory cytokine levels, protecting intestinal epithelial cells, promoting mucosal barrier repair and regulating intestinal microbiota. In addition, CuL NCs have been found to enhance cellular antioxidant and anti-inflammatory capacities by regulating the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) oxidative stress pathway and nuclear factor kappa B (NF-κB) signaling pathway, respectively. Notably, CuL NCs demonstrate significant prophylactic and therapeutic efficacy in mouse models with typical IBD, including ulcerative colitis (UC) and Crohn's disease (CD). This study provides a new approach for building multifaceted therapeutic platforms for natural products to treat IBD.

Luteolin in Inflammatory Bowel Disease and Colorectal Cancer: A Disease Continuum Perspective

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that may progress to colorectal cancer (CRC), presenting significant challenges to global health. With shifts in lifestyle, the incidence of both conditions continues to rise, underscoring the urgent need for effective treatments. While traditional therapies can be effective, their high recurrence rates and associated adverse reactions limit their broader application. Luteolin, a flavonoid derived from natural plants, has emerged as a promising focus in both IBD and CRC research due to its multi-target therapeutic potential. This article reviews the molecular mechanisms and signaling pathways through which luteolin regulates immune cell differentiation, mitigates inflammation and oxidative stress, modulates gut microbiota, and restores intestinal mucosal barrier function in IBD. In the context of CRC, luteolin demonstrates significant anti-tumor effects by inhibiting cancer cell proliferation, inducing apoptosis, and suppressing cell migration and invasion. Notably, luteolin has demonstrated significant improvements in IBD symptoms by influencing the differentiation of T cell subsets, decreasing the expression of inflammatory mediators, activating antioxidant pathways, and enhancing the structure of gut microbiota. Furthermore, advancements in formulation technology, such as the use of polymer micelles and responsive nanoparticles, have greatly improved the bioavailability and efficacy of luteolin. However, further investigation is needed to address the bioavailability and potential toxicity of luteolin, particularly in the critical transition from IBD to CRC. This article emphasizes the potential of luteolin in the treatment of IBD and CRC and anticipates its promising prospects for future clinical applications as a natural therapeutic agent.

Precision therapeutics for inflammatory bowel disease: advancing ROS-responsive nanoparticles for targeted and multifunctional drug delivery

Inflammatory bowel disease (IBD) is a severe chronic intestinal disorder with a rising global incidence. Current therapies, including the delivery of anti-inflammatory drugs and probiotics, face significant challenges in terms of safety, stability, and efficacy. In IBD patients, the activity of antioxidant enzymes (e.g., superoxide dismutase, glutathione peroxidase, and glutathione reductase) is reduced at the site of intestinal inflammation, leading to the accumulation of reactive oxygen species (ROS). This accumulation damages the intestinal mucosa, disrupts tight junctions between cells, and compromises the integrity of the intestinal barrier, exacerbating IBD symptoms. Therefore, nanoparticles responsive to ROS and capable of mimicking antioxidant enzyme activity, such as boronates, polydopamine, sulfides, and metal nanozymes, have emerged as promising tools. These nanoparticles can respond to elevated ROS levels in inflamed intestinal regions and release drugs to effectively neutralize ROS, making them ideal candidates for IBD treatment. This review discusses the application of various ROS-responsive nanomaterial delivery systems in IBD therapy, highlights current challenges, and outlines future research directions. Furthermore, we explore the "layered programmable delivery" strategy, which combines ROS-responsive nanoparticles with pH-responsive and cell membrane-targeted nanoparticles. This strategy has the potential to overcome the limitations of single-mechanism targeted drug delivery, enabling multi-range and multi-functional treatment approaches that significantly enhance delivery efficiency, providing new insights for the future of localized IBD treatment.

An Oral H2S Responsive Cu5.4O Nanozyme Platform with Strong ROS/H2S Scavenging Capacity for the Treatment of Colitis

Inflammatory bowel disease involves excess reactive oxygen species (ROS) and hydrogen sulfide (H2S) at inflammatory sites. Nanozyme-mediated ROS and H2S scavenging therapy is promising for colitis treatment. Here, we synthesized a multiple ROS scavenging Cu5.4O nanoparticle and first explored its H2S scavenging capacity. Chitosan oligosaccharide modified with alpha-lipoic acid was coated on the nanoparticles to further enhance the H2S scavenging capacity. Furthermore, calcium alginate was coated on the surface to develop an oral nanoplatform (Cu5.4O@SAG) possessing dual-pH/H2S-responsive release characteristics. Importantly, Cu5.4O@SAG exhibited enrichment at the colonic inflammation site and relieved the inflammatory index, containing the recovery of colon length, spleen index, liver index, and body weight, as well as inflammatory cell infiltration. In vivo and in vitro experiments revealed the dual ROS and H2S scavenging capacities of the nanoplatform. Additionally, Cu5.4O@SAG regulated tight junctions, mucus layers, and gut microbiota, which was accompanied by the downregulation of inflammatory cytokines. Notably, Cu5.4O@SAG also had excellent biocompatibility. In conclusion, this oral multiple-scavenging nanozyme platform provides a new and safe paradigm for the development of nanozymes for colitis treatment.

A Comprehensive Review of Challenges in Oral Drug Delivery Systems and Recent Advancements in Innovative Design Strategies

The oral route of drug administration is often preferred by patients and healthcare providers due to its convenience, ease of use, non-invasiveness, and patient acceptance. However, traditional oral dosage forms have several limitations, including low bioavailability, limited drug loading capacity, and stability and storage issues, particularly with solutions and suspensions. Over the years, researchers have dedicated considerable effort to developing novel oral drug delivery systems to overcome these limitations. This review discusses various challenges associated with oral drug delivery systems, including biological, pharmaceutical, and physicochemical barriers. It also explores common delivery approaches, such as gastroretentive drug delivery, small intestine drug delivery, and colon-targeting drug delivery systems. Additionally, numerous strategies aimed at improving oral drug delivery efficiency are reviewed, including solid dispersion, absorption enhancers, lipidbased formulations, nanoparticles, polymer-based nanocarriers, liposomal formulations, microencapsulation, and micellar formulations. Furthermore, innovative approaches like orally disintegrating tablets (ODT), orally disintegrating films (ODF), layered tablets, micro particulates, self-nano emulsifying formulations (SNEF), and controlled release dosage forms are explored for their potential in enhancing oral drug delivery efficiency and promoting patients' compliance. Overall, this review highlights significant progress in addressing challenges in the pharmaceutical industry and clinical settings, offering novel approaches for the development of effective oral drug delivery systems.

Anti-Graying Effects of External and Internal Treatments with Luteolin on Hair in Model Mice

Little is known about the anti-graying effects of antioxidants on hair. The anti-graying effects of three antioxidants (luteolin, hesperetin, and diosmetin) on hair were investigated according to the sequential processes of hair graying that were previously clarified in model mice [Ednrb(+/-);RET-mice]. External treatment with luteolin, but not that with hesperetin or diosmetin, alleviated hair graying in Ednrb(+/-);RET-mice. Internal treatment with luteolin also mitigated hair graying in the mice. Although both luteolin treatments had very limited effects on hair cycles, the treatments suppressed the increase in p16ink4a-positive cells in bulges [senescent keratinocyte stem cells (KSCs)]. Both of the treatments also suppressed decreases in the expression levels of endothelins in KSCs and their receptor (Ednrb) in melanocyte stem cells (MSCs) and alleviated hair graying in the mice. Luteolin is a special antioxidant with an anti-graying potency through improvement of age-related dysfunction in signaling between endothelins in KSCs and their receptor in MSCs. Luteolin for topical and oral use is commercially available to people in the form of supplements. Similar processes of hair graying in Ednrb(+/-);RET-mice and humans have been reported. These results are encouraging for the practical application of luteolin as a medicine with an anti-graying effect on hair in humans.

MnNi@PVP Nanoenzyme Based on Regulating Inflammation and Immune Homeostasis for the Therapy of Inflammatory Bowel Disease

Nanozymes exhibiting remarkable antioxidant capabilities represent an effective therapeutic approach for ulcerative colitis (UC). This study synthesized the MnNi@PVP nanoenzyme through high-temperature pyrolysis and the NaCl template method, which exhibited multienzyme activity comprising glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). This study investigated the therapeutic effect of MnNi@PVP on colitis caused by sodium dextran sulfate (DSS). The findings indicated that MnNi@PVP notably decreased the disease activity index (DAI) score, which encompasses weight loss, colon shortening, and histopathological changes. MnNi@PVP showed effectiveness in addressing oxidative damage and suppressing the levels of proinflammatory markers, such as tumor necrosis factor (TNF-α), inducible nitric oxide synthase (iNOS), and interleukin (IL)-6, by inactivating the TLR4 pathway and macrophages. In addition, MnNi@PVP demonstrated the ability to repair tight junction proteins (occludin and ZO-1) and restore the intestinal barrier. The transcriptome sequencing demonstrated that MnNi@PVP could regulate inflammatory factor expression pathways and immune processes. Additionally, negatively charged MnNi@PVP can selectively bind to inflamed colonic tissues through electrostatic interactions, endowing it with targeted reparative capabilities at the location of intestinal inflammation. The MnNi@PVP, which possesses the reactive oxygen and nitrogen species (RONS) clearance capability examined in this section, is expected to provide the basis for the targeted repair of intestinal function.

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

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

A Novel Curcumin-Loaded Nanoplatform Alleviates Osteoarthritis by Inhibiting Chondrocyte Ferroptosis

Osteoarthritis (OA) is a chronic degenerative joint disease characterized by the degradation of articular cartilage. Recent studies have demonstrated that chondrocyte ferroptosis plays a crucial role in the progression of OA. Consequently, developing nanomedicines that suppress chondrocyte ferroptosis is a promising strategy for OA treatment. However, there are few reports on nanomedicines specifically targeting chondrocyte ferroptosis for OA therapy. In this study, Curcumin-loaded nanoparticles (Cur-NPs) are fabricated to suppress chondrocyte ferroptosis by regulating reactive oxygen species (ROS), ferrous ion (Fe2⁺), and Acyl-CoA Synthetase Long-Chain Family Member 4 (ACSL4) levels of chondrocyte. This is achieved by combining the functions of curcumin and an amphiphilic block copolymer with ROS scavenging and iron-chelating properties. The in vitro anti-ferroptotic effects of Cur-NPs are thoroughly investigated. The findings indicate that Cur-NPs decrease the expression of ferroptosis markers such as ROS, Fe2⁺, and ACSL4, while protecting the mitochondrial membrane potential of chondrocytes. Additionally, Cur-NPs attenuated lipid peroxidation in chondrocytes. Furthermore, Cur-NPs significantly reduced the expression of the catabolic factor Matrix Metallopeptidase 13 (MMP13) and increased the expression of the anabolic factor Collagen type II (Col II) in vitro. This study demonstrates that Cur-NPs exhibit enhanced chondroprotective effects through anti-ferroptotic actions, presenting a promising approach for inhibiting chondrocyte ferroptosis using bioactive nanomaterials in OA treatment.

Nanotechnology for Targeted Inflammatory Bowel Disease Therapy: Challenges and Opportunities

Inflammatory bowel disease (IBD) is a complex and recurring inflammatory disorder that affects the gastrointestinal tract and is influenced by genetic predisposition, immune dysregulation, the gut microbiota, and environmental factors. Advanced therapies, such as biologics and small molecules, target diverse immune pathways to manage IBD. Nanoparticle (NP)-based drugs have emerged as effective tools, offering controlled drug release and targeted delivery. This review highlights NP modifications for anti-inflammatory purposes, utilizing changes such as those in size, charge, redox reactions, and ligand-receptor interactions in drug delivery systems. By using pathological and microenvironmental cues to guide NP design, precise targeting can be achieved. In IBD, a crucial aspect of NP intervention is targeting specific types of cells, such as immune and epithelial cells, to address compromised intestinal barrier function and reduce overactive immune responses. This review also addresses current challenges and future prospects, with the goal of advancing the development of NP-mediated strategies for IBD treatment.

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.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

Nanomedicine for T-Cell Mediated Immunotherapy

T-cell immunotherapy offers outstanding advantages in the treatment of various diseases, and with the selection of appropriate targets, efficient disease treatment can be achieved. T-cell immunotherapy has made great progress, but clinical results show that only a small proportion of patients can benefit from T-cell immunotherapy. The extensive mechanistic work outlines a blueprint for using T cells as a new option for immunotherapy, but also presents new challenges, including the balance between different fractions of T cells, the inherent T-cell suppression patterns in the disease microenvironment, the acquired loss of targets, and the decline of T-cell viability. The diversity, flexibility, and intelligence of nanomedicines give them great potential for enhancing T-cell immunotherapy. Here, how T-cell immunotherapy strategies can be adapted with different nanomaterials to enhance therapeutic efficacy is discussed. For two different pathological states, immunosuppression and immune activation, recent advances in nanomedicines for T-cell immunotherapy in diseases such as cancers, rheumatoid arthritis, systemic lupus erythematosus, ulcerative colitis, and diabetes are summarized. With a focus on T-cell immunotherapy, this review highlights the outstanding advantages of nanomedicines in disease treatment, and helps advance one's understanding of the use of nanotechnology to enhance T-cell immunotherapy.

The development of nanocarriers for natural products

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

Plant exosome-like nanovesicles derived from sesame leaves as carriers for luteolin delivery: Molecular docking, stability and bioactivity

The growing recognition of luteolin (Lu) as a vital functional component is attributed to its notable bioactive properties. However, the effective use of Lu is hindered by its inherent limitations related to water solubility, stability, and bioavailability. Here, we aim to develop sesame leaves-derived exosome-like nanovesicles (Exo) for Lu delivery (Exo@Lu) as vehicles. The encapsulation mechanism, solubility, stability, and bioactivity of Exo@Lu were thoroughly evaluated. Exo enriched abundant lipids, proteins, and phenolic compounds with an encapsulation efficiency of ∼ 91.9 % and a loading capacity of ∼ 20.5 % for Lu. The primary binding forces responsible for the encapsulation were hydrogen bonds and van der Waals forces. After encapsulation, the water solubility and stability of Lu were significantly improved under various conditions, including thermal, light, storage, ionic strength, and pH. Exo@Lu maintained structural integrity during simulated digestion, enhancing bioaccessibility and efficacy in mitigating oxidative stress and inflammatory response compared to Exo and free Lu.

Post cross-linked ROS-responsive poly(β-amino ester)-plasmid polyplex NPs for gene therapy of EBV-associated nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common tumors in South China and Southeast Asia and is thought to be associated with Epstein-Barr virus (EBV) infection. Downregulation of latent membrane protein 1 (LMP1) encoded by EBV can reduce the expression of NF-κB and PI3K, induce apoptosis, and inhibit the growth of EBV-related NPC. For targeted cleavage of the Lmp1 oncogene via the CRISPR/Cas9 gene editing system, a post cross-linked ROS-responsive poly(β-amino ester) (PBAE) polymeric vector was developed for the delivery of CRISPR/Cas9 plasmids both in vitro and in vivo. After composition optimization, the resultant polymer-plasmid polyplex nanoparticles (NPs) showed a diameter of ∼230 nm and a zeta potential of 22.3 mV with good stability. Compared with the non-cross-linked system, the cross-linked NPs exhibited efficient and quick cell uptake, higher transfection efficiency in EBV-positive C666-1 cells (53.5% vs. 40.6%), more efficient gene editing ability against the Mucin2 model gene (Muc2) (17.9% vs. 15.4%) and Lmp1 (8.5% vs. 5.6%), and lower intracellular reactive oxygen species (ROS) levels. The NPs achieved good tumor penetration and tumor growth inhibition in the C666-1 xenograft tumor model via Lmp1 cleavage, indicating their potential for gene therapy of EBV-related NPC.

Combined ROS Responsive Polydopamine-Coated Berberine Nanoparticles Effective Against Ulcerative Colitis in Mouse Model

Introduction

Enhancing the efficacy of berberine (BBR) in the treatment of ulcerative colitis (UC) through the development of dopamine-coated berberine nanoparticles (PDA@BBR NPs) with ROS-responsive and adhesive properties.

Methods

Berberine nanoparticles (BBR NPs) were synthesized using the nonsolvent precipitation method, and their surfaces were coated with polydopamine (PDA) through oxidative polymerization. The PDA@BBR NPs were characterized by transmission electron microscopy (TEM), size analysis, and zeta potential analysis. Drug loading and encapsulation efficiency were analyzed using fluorescence spectroscopy. The responsiveness of these nanoparticles to reactive oxygen species (ROS) was assessed in vitro, while their adhesive properties and therapeutic efficacy on UC were evaluated in vivo.

Results

Physicochemical property studies showed that PDA coated BBR NPs nanoparticles have good dispersion and stability. In vitro results showed that PDA@BBR NPs could prolong the retention time of the drug at the colonic site and could realize the gradual drug release under ROS environment. In addition, animal studies showed that PDA@BBR NPs exhibited significant anti-inflammatory effects on DSS-induced colitis and effectively reduced intestinal mucosal damage.

Conclusion

PDA@BBR NPs are ROS-responsive nanoparticles that adhere well and have a high drug loading capacity. They have shown therapeutic effects in mice with UC, indicating that this formulation may be a promising treatment option.

Synergistic effects of multidrug/material combination deliver system for anti-mutidrug-resistant tumor

Multidrug resistance (MDR) is a public health issue of particular concern, for which nanotechnology-based multidrug delivery systems are considered among the most effective suppressive strategies for such resistance in tumors. However, for such strategies to be viable, the notable shortcomings of reduced loading efficiency and uncontrollable drug release ratio need to be addressed. To this end, we developed a novel "multidrug/material" co-delivery system, using d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS, P-gp efflux pump inhibitor) and poly(amidoamine) (PAMAM) to fabricate a precursor material with the properties of reversing MDR and having a long-cycle. Further, to facilitate multidrug co-delivery, we loaded doxorubicin(Dox) and curcumin(Cur, cardiotoxicity modifier and P-gp inhibitor) into PAMAM-TPGS nano-micelles respectively, and mixed in appropriate proportions. The multidrug/material co-delivery system thus obtained was characterized by high drug loading and a controllable drug release ratio in the physiological environment. More importantly, in vitro and in vivo pharmacodynamic studies indicated that the multidrug/material co-delivery system facilitated the reversal of MDR. Moreover, the system has increased anti-tumor activity and is biologically safe. We accordingly propose that the "multidrug/material" co-delivery system developed in this study could serve as a potential platform for reversing MDR and achieving safe and effective clinical treatment.

The progression of inorganic nanoparticles and natural products for inflammatory bowel disease

There is a growing body of evidence indicating a close association between inflammatory bowel disease (IBD) and disrupted intestinal homeostasis. Excessive production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with an increase in M1 proinflammatory macrophage infiltration during the activation of intestinal inflammation, plays a pivotal role in disrupting intestinal homeostasis in IBD. The overabundance of ROS/RNS can cause intestinal tissue damage and the disruption of crucial gut proteins, which ultimately compromises the integrity of the intestinal barrier. The proliferation of M1 macrophages contributes to an exaggerated immune response, further compromising the intestinal immune barrier. Currently, intestinal nanomaterials have gained widespread attention in the context of IBD due to their notable characteristics, including the ability to specifically target regions of interest, clear excess ROS/RNS, and mimic biological enzymes. In this review, we initially elucidated the gut microenvironment in IBD. Subsequently, we delineate therapeutic strategies involving two distinct types of nanomedicine, namely inorganic nanoparticles and natural product nanomaterials. Finally, we present a comprehensive overview of the promising prospects associated with the application of nanomedicine in future clinical settings for the treatment of IBD (graphic abstract). Different classes of nanomedicine are used to treat IBD. This review primarily elucidates the current etiology of inflammatory bowel disease and explores two prominent nanomaterial-based therapeutic approaches. First, it aims to eliminate excessive reactive oxygen species and reactive nitrogen species. Second, they focus on modulating the polarization of inflammatory macrophages and reducing the proportion of pro-inflammatory macrophages. Additionally, this article delves into the treatment of inflammatory bowel disease using inorganic metal nanomaterials and natural product nanomaterials.

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

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

Nano-scale drug delivery systems for luteolin: advancements and applications

Luteolin (Lu) is a naturally occurring flavonoid compound with a diverse array of pharmacological activities, including anti-tumor, anti-inflammatory, antibacterial, and neuroprotective properties. However, the therapeutic efficacy and clinical application of Lu are significantly hindered by inherent limitations, such as poor water solubility, short half-life, low bioavailability, and potential off-target toxicity. Recent studies have demonstrated that the utilization of nanocarriers presents a promising strategy to enhance the solubility of Lu, prolong its circulation time, and improve its targeting ability. Despite numerous reviews over the past few decades having focused on the source, pharmacological activities, and molecular mechanisms of Lu, there exists a conspicuous gap in the literature regarding a comprehensive review of Lu-loaded nanoformulations and their applications. To address this gap, we present an exhaustive overview of the advancements and applications of nano-scale drug delivery systems specifically designed for Lu. These platforms encompass micelles, nanocarrier-based systems, emulsified drug delivery systems, and vesicular drug delivery systems. We provide detailed insights into the synthetic materials, preparation methods, physicochemical properties, and significant outcomes associated with these nanoformulations. This systematic review will be particularly valuable to researchers seeking novel avenues in the field of nano-delivery strategies and exploring the potential clinical applications of Lu.

ROS-responsive phenylboronic ester-based nanovesicles as multifunctional drug delivery systems for the treatment of inflammatory and thrombotic complications

Inflammatory and thrombotic complications and a low loading of dual drugs with different hydrophilicities remain challenges to treat thrombosis with drug delivery systems (DDSs). Here, the reactive oxygen species (ROS)-responsive amphiphilic block polymer poly(ethylene glycol)-b-2-((((4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)oxy)carbonyl)oxy)-ethyl methacrylate (PEG-b-PTBEM) was synthesized and nanovesicles (PPTV) were prepared successfully for the drug delivery platform by controlling the hydrophilic/hydrophobic ratio of molecular chains and molecular self-assembly. The anti-inflammatory drug indomethacin (IDM) was loaded in the wall of nanovesicles and the thrombolytic enzyme nattokinase (NK) was encapsulated in the aqueous cavity of nanovesicles. Both drugs could be rapidly released at the site of thrombosis and/or inflammation with an excessive ROS concentration. The dual drug-loaded nanovesicles not only eliminated ROS, but also alleviated inflammation and dissolved the generated thrombus, showing significant therapeutic efficacy in the in vivo mouse model of carrageenan tail thrombosis. Therefore, drug-delivery nanovesicles play multiple roles in the treatment of inflammation-induced thrombotic disorders, which offer a promising treatment for inflammatory and thrombotic complications.

Paclitaxel-loaded ROS-responsive nanoparticles for head and neck cancer therapy

High intracellular reactive oxygen species (ROS) level is characteristic of cancer cells and could act as a target for the efficient targeted drug delivery for cancer treatment. Consequently, biomaterials that react to excessive levels of ROS are essential for biomedical applications. In this study, a novel ROS-responsive polymer based on D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly (β-thioester) (TPGS-PBTE) was synthesized for targeted delivery of the first-line antineoplastic drug, paclitaxel (PTX). The resultant TPGS-PBTE NPs showed good ROS-responsive capability in size change and drug release. Compared to PTX, PTX-loaded nanoparticles (PTX@TPGS-PBTE NPs) showed enhanced cytotoxicity and higher level of apoptosis toward squamous cell carcinoma (SCC-7) cells. Tumor-targeted delivery of the NPs was also observed, especially after being modified with a tumor-targeting peptide, cRGD. Enhanced tumor growth inhibition was also observed in head and neck cancer SCC-7 murine models. In summary, PTX@TPGS-PBTE NPs can achieve good therapeutic effects of PTX against head and neck cancer both in vitro and in vivo, especially when modified by cRGD for active targeting, which enriched the application of ROS responsive system utilized in the delivery of anticancer drugs.

Responsive nanosystems for targeted therapy of ulcerative colitis: Current practices and future perspectives

The pharmacological approach to treating gastrointestinal diseases is suffering from various challenges. Among such gastrointestinal diseases, ulcerative colitis manifests inflammation at the colon site specifically. Patients suffering from ulcerative colitis notably exhibit thin mucus layers that offer increased permeability for the attacking pathogens. In the majority of ulcerative colitis patients, the conventional treatment options fail in controlling the symptoms of the disease leading to distressing effects on the quality of life. Such a scenario is due to the failure of conventional therapies to target the loaded moiety into specific diseased sites in the colon. Targeted carriers are needed to address this issue and enhance the drug effects. Conventional nanocarriers are mostly readily cleared and have nonspecific targeting. To accumulate the desired concentration of the therapeutic candidates at the inflamed area of the colon, smart nanomaterials with responsive nature have been explored recently that include pH responsive, reactive oxygen species responsive (ROS), enzyme responsive and thermo - responsive smart nanocarrier systems. The formulation of such responsive smart nanocarriers from nanotechnology scaffolds has resulted in the selective release of therapeutic drugs, avoiding systemic absorption and limiting the undesired delivery of targeting drugs into healthy tissues. Recent advancements in the field of responsive nanocarrier systems have resulted in the fabrication of multi-responsive systems i.e. dual responsive nanocarriers and derivitization that has increased the biological tissues and smart nanocarrier's interaction. In addition, it has also led to efficient targeting and significant cellular uptake of the therapeutic moieties. Herein, we have highlighted the latest status of the responsive nanocarrier drug delivery system, its applications for on-demand delivery of drug candidates for ulcerative colitis, and the prospects are underpinned.

Engineered baicalein-decorated zinc phosphates for synergistic alleviation of inflammatory bowel disease by repairing the mucosal barrier and relieving oxidative stress

Orally administered baicalein-decorated zinc phosphates (ZnBM) were engineered for mucosal barrier improvement and intestinal inflammation relief. ZnBM with a size of 1.78 μm comprised 5.58 wt% baicalein and 13.17 wt% zinc. The incorporation of baicalein endowed ZnBM with excellent radical scavenging activities. ZnBM exhibited good stability with negligible zinc release in PBS solution for 2 days, and 32.82% of the zinc could reach the gut. In addition, ZnBM polarized macrophages into the anti-inflammatory M2 type and effectively scavenged intracellular reactive oxygen species (ROS) of lipopolysaccharide (LPS)-treated RAW264.7. Meanwhile, ZnBM effectively scavenged intracellular ROS of phorbol 12-myristate 13-acetate (PMA)-induced Caco-2 cells and exerted a reparative effect on the LPS-damaged Caco-2 monolayer, causing an obvious improvement of the barrier function. Reduced systemic exposure to FITC-dextran was observed to illustrate barrier restoration by ZnBM, which was achieved through upregulation of tight junction protein expression. Notably, the commonly used clinical drug 5-aminosalicylic acid is toxic to the liver and kidneys, and commercial ZnO caused the death of mice during treatment. Apparently, the therapeutic effect of ZnBM was significantly better than that of baicalein alone in chronic colitis. Overall, ZnBM exhibited outstanding therapeutic efficacy and is expected to treat colitis due to its effectiveness, biosecurity, facile preparation, and easy storage.

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

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

Injectable Bioadhesive Hydrogels Scavenging ROS and Restoring Mucosal Barrier for Enhanced Ulcerative Colitis Therapy

Despite the progress in the therapy of ulcerative colitis (UC), long-lasting UC remission can hardly be achieved in the majority of UC patients. The key pathological characteristics of UC include an impaired mucosal barrier and local inflammatory infiltration. Thus, a two-pronged approach aiming at repairing damaged mucosal barrier and scavenging inflammatory mediators simultaneously might hold great potential for long-term remission of UC. A rectal formulation can directly offer preferential and effective drug delivery to inflamed colon. However, regular intestinal peristalsis and frequent diarrhea in UC might cause transient drug retention. Therefore, a bioadhesive hydrogel with strong interaction with intestinal mucosa might be preferable for rectal administration to prolong drug retention. Here, we designed a bioadhesive hydrogel formed by the cross-linking of sulfhydryl chondroitin sulfate and polydopamine (CS-PDA). The presence of PDA would ensure the mucosa-adhesive behavior, and the addition of CS in the hydrogel network was expected to achieve the restoration of the intestinal epithelial barrier. To scavenge the key player (excessive reactive oxygen species, ROS) in inflamed colon, sodium ferulic (SF), a potent ROS inhibitor, was incorporated into the CS-PDA hydrogel. After rectal administration, the SF-loaded CS-PDA hydrogel could adhere to the colonic mucosa to allow prolonged drug retention. Subsequently, sustained SF release could be achieved to persistently scavenge ROS in inflammatory areas. Meanwhile, the presence of CS would promote the restoration of the mucosal barrier. Ultimately, scavenging ROS and restoring the mucosal barrier could be simultaneously achieved via this SF-loaded bioadhesive hydrogel scaffold. Our two-pronged approach might provide new insight for effective UC treatment.

Oral delivery of porous starch-loaded bilayer microgels for controlled drug delivery and treatment of ulcerative colitis

We prepared one type of bilayer microgels for oral administration with three effects: pH responsiveness, time lag, and colon enzyme degradation. Combined with the dual biological effects of curcumin (Cur) for reducing inflammation and promoting repair of colonic mucosal injury, targeted colonic localization and release of Cur according to the colonic microenvironment were enhanced. The inner core, derived from guar gum and low-methoxyl pectin, afforded colonic adhesion and degradation behavior; the outer layer, modified by alginate and chitosan via polyelectrolyte interaction, achieved colonic localization. The porous starch (PS)-mediated strong adsorption allowed Cur loading in inner core to achieve a multifunctional delivery system. In vitro, the formulations exhibited good bioresponses at different pH conditions, potentially delaying Cur release in the upper gastrointestinal tract. In vivo, dextran sulfate sodium-induced ulcerative colitis (UC) symptoms were significantly alleviated after oral administration, accompanied by reduced levels of inflammatory factors. The formulations facilitated colonic delivery, allowing Cur accumulation in colonic tissue. Moreover, the formulations could alter gut microbiota composition in mice. During Cur delivery, each formulation increased species richness, decreased pathogenic bacterial content, and afforded synergistic effects against UC. These PS-loaded bilayer microgels, exhibiting excellent biocompatibility, multi-bioresponsiveness, and colon targeting, could be beneficial in UC therapy, allowing development into a novel oral formulation.

Nanoparticle-Mediated Delivery of Flavonoids: Impact on Proinflammatory Cytokine Production: A Systematic Review

Flavonoids are a diverse group of plant-derived compounds that have been shown to have various health benefits, including anti-inflammatory effects. However, their use in the treatment of inflammatory diseases has been limited due to their low bioavailability. The nanoparticle-mediated delivery of flavonoids has been proposed as a potential solution to this issue, as it allows the sustained release of the flavonoids over time. There are several different nanoparticle systems that have been developed for flavonoid delivery, including polymeric nanoparticles, liposomes, and inorganic nanoparticles. This systematic review aims to evaluate the impact of nanoparticle-mediated delivery of flavonoids on pro-inflammatory cytokine production in various diseases. We analyzed the performance of flavonoid-encapsulated nanoparticles in regulating cytokine production in different in vitro and in vivo studies. To this end, we followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to conduct a comprehensive search of the literature and to assess the quality of the included studies. The results showed that flavonoid-encapsulated nanoparticles significantly downregulated pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-6, and IL-18. In some cases, this effect was significantly greater than that observed with non-encapsulated flavonoids These findings suggest that nanoparticle-mediated delivery of flavonoids may have potential as a therapeutic approach for the treatment of inflammatory diseases.

Recent updates on correlation between reactive oxygen species and synbiotics for effective management of ulcerative colitis

Ulcerative colitis (UC) is presently considered a multifactorial pathology, which may lead to persistent inflammatory action of the gastrointestinal tract (GIT) because of an improperly managed immunological reactivity to the intestinal microbiota found in the GIT. The immune response to common commensal microbes plays an essential role in intestinal inflammation related to UC synbiotics, and it is an important element in the optimal therapy of UC. Therefore, synbiotics, i.e., a mixture of prebiotics and probiotics, may help control the diseased state. Synbiotics alleviate the inflammation of the colon by lowering the reactive oxygen species (ROS) and improving the level of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). Prebiotic supplementation is not a common practice at the moment, despite numerous research findings proving that the benefits of both probiotics and prebiotics encourage their continued existence and positioning in the GIT, with positive effects on human health by managing the inflammatory response. However, the fact that there have been fewer studies on the treatment of UC with different probiotics coupled with selected prebiotics, i.e., synbiotics, and the outcomes of these studies have been very favorable. This evidence-based study explores the possible role of ROS, SOD, and synbiotics in managing the UC. The proposed review also focuses on the role of alteration of gut microbiota, antioxidant defense in the gastrointestinal tract, and the management of UC. Thus, the current article emphasizes oxidative stress signaling in the GI tract, oxidative stress-based pathomechanisms in UC patients, and UC therapies inhibiting oxidative stress' effects.

Self-Homeostasis Immunoregulatory Strategy for Implant-Related Infections through Remodeling Redox Balance

Implant-related infections (IRIs) are catastrophic complications after orthopedic surgery. Excess reactive oxygen species (ROS) accumulated in IRIs create a redox-imbalanced microenvironment around the implant, which severely limits the curing of IRIs by inducing biofilm formation and immune disorders. However, current therapeutic strategies commonly eliminate infection utilizing the explosive generation of ROS, which exacerbates the redox imbalance, aggravating immune disorders and promoting infection chronicity. Herein, a self-homeostasis immunoregulatory strategy based on a luteolin (Lut)-loaded copper (Cu²⁺)-doped hollow mesoporous organosilica nanoparticle system (Lut@Cu-HN) is designed to cure IRIs by remodeling the redox balance. In the acidic infection environment, Lut@Cu-HN is continuously degraded to release Lut and Cu²⁺. As both an antibacterial and immunomodulatory agent, Cu²⁺ kills bacteria directly and promotes macrophage pro-inflammatory phenotype polarization to activate the antibacterial immune response. Simultaneously, Lut scavenges excessive ROS to prevent the Cu²⁺-exacerbated redox imbalance from impairing macrophage activity and function, thus reducing Cu²⁺ immunotoxicity. The synergistic effect of Lut and Cu²⁺ confers excellent antibacterial and immunomodulatory properties to Lut@Cu-HN. As demonstrated in vitro and in vivo, Lut@Cu-HN self-regulates immune homeostasis through redox balance remodeling, ultimately facilitating IRI eradication and tissue regeneration.

Potential applications of drug delivery technologies against radiation enteritis

INTRODUCTION

The incidence of abdominal tumors, such as colorectal and prostate cancers, continually increases. Radiation therapy is widely applied in the clinical treatment of patients with abdominal/pelvic cancers, but it often unfortunately causes radiation enteritis (RE) involving the intestine, colon, and rectum. However, there is a lack of suitable treatment options for effective prevention and treatment of RE.

AREAS COVERED

Conventional clinical drugs for preventing and treating RE are usually applied by enemas and oral administration. Innovative gut-targeted drug delivery systems including hydrogels, microspheres, and nanoparticles are proposed to improve the prevention and curation of RE.

EXPERT OPINION

The prevention and treatment of RE have not attracted sufficient attention in the clinical practice, especially compared to the treatment of tumors, although RE takes patients great pains. Drug delivery to the pathological sites of RE is a huge challenge. The short retention and weak targeting of conventional drug delivery systems affect the therapeutic efficiency of anti-RE drugs. Novel drug delivery systems including hydrogels, microspheres, and nanoparticles can allow drugs long-term retention in the gut and targeting the inflammation sites to alleviate radiation-induced injury.

The role and mechanism of flavonoid herbal natural products in ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disease of the intestine that presents clinically with abdominal pain, mucopurulent stools, and posterior urgency. The lesions of UC are mainly concentrated in the rectal and colonic mucosa and submucosa. For patients with mild to moderate UC, the best pharmacological treatment includes glucocorticoids, immunosuppressants, antibiotics, and biologics, but the long-term application can have serious toxic side effects. Currently, nearly 40% of UC patients are treated with herbal natural products in combination with traditional medications to reduce the incidence of toxic side effects. Flavonoid herbal natural products are the most widely distributed polyphenols in plants and fruits, which have certain antioxidant and anti-inflammatory activities. Flavonoid herbal natural products have achieved remarkable efficacy in the treatment of UC. The pharmacological mechanisms are related to anti-inflammation, promotion of mucosal healing, maintenance of intestinal immune homeostasis, and regulation of intestinal flora. In this paper, we summarize the flavonoid components of anti-ulcerative colitis and their mechanisms reported in the past 10 years, to provide a basis for rational clinical use and the development of new anti-ulcerative colitis drugs.

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

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

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

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

A Biomarker-Responsive Nanosystem with Colon-Targeted Delivery for Ulcerative Colitis's Detection and Treatment with Optoacoustic/NIR-II Fluorescence Imaging

Ulcerative colitis (UC) is a prevalent idiopathic inflammatory disease which causes such complications as intestinal perforation, obstruction, and bleeding, and thus deleteriously impacting people's normal work and quality of life. Hence, accurate diagnosis of UC is crucial in terms of planning optimal treatment plan. Herein, a pH/reactive oxygen species (ROS) dual-responsive nanosystem (BM@EP) is developed for UC's detection and therapy. BM@EP is composed of a chromophore-drug dyad and the enteric coating. The chromophore-drug dyad (BOD-XT-DHM) is synthesized by linking the chromophore (BOD-XT-BOH) and a flavonoid drug (dihydromyricetin DHM) through boronate ester bond. The enteric coating includes Eudragit S100 and poly(lactic-co-glycolic acid) (PLGA), the former is commonly employed as a pH-dependent polymer coating excipient so as to attain colon-targeted delivery, and the latter has been widely used as an excipient for the controlled-extended release. After oral administration, BM@EP delivers the dyad (BOD-XT-DHM) into the colon and releases the dyad molecules by being triggered by the alkaline pH in t colon, thereafter upon being stimulated by overexpressed H₂ O₂ in the inflamed colon, the boronate bond in the dyad is broken down and correspondingly the drug DHM is released for UC therapy, simultaneously the chromophore is released for near-infrared second window (NIR-II) fluorescence and optoacoustic imaging for UC diagnosis and recovery evaluation.

Enhancing the therapeutic efficacy of nanoparticles for cancer treatment using versatile targeted strategies

Poor targeting of therapeutics leading to severe adverse effects on normal tissues is considered one of the obstacles in cancer therapy. To help overcome this, nanoscale drug delivery systems have provided an alternative avenue for improving the therapeutic potential of various agents and bioactive molecules through the enhanced permeability and retention (EPR) effect. Nanosystems with cancer-targeted ligands can achieve effective delivery to the tumor cells utilizing cell surface-specific receptors, the tumor vasculature and antigens with high accuracy and affinity. Additionally, stimuli-responsive nanoplatforms have also been considered as a promising and effective targeting strategy against tumors, as these nanoplatforms maintain their stealth feature under normal conditions, but upon homing in on cancerous lesions or their microenvironment, are responsive and release their cargoes. In this review, we comprehensively summarize the field of active targeting drug delivery systems and a number of stimuli-responsive release studies in the context of emerging nanoplatform development, and also discuss how this knowledge can contribute to further improvements in clinical practice.