Effect of particle size on the cellular uptake and anti-inflammatory activity of oral nanotherapeutics

Hepatocytes and mitochondria dual-targeted astaxanthin WPI-SCP nanoparticles for the alleviation of alcoholic liver injury

Alcoholic liver injury is one of the most frequent liver diseases around the world, and nutritional intervention has been considered as an effective way to alleviate alcohol liver injury. To alleviate the liver damage caused by alcohol, a type of astaxanthin (AXT) loaded nanoparticles were designed for dual targeting of hepatocytes and mitochondria. Firstly, galactooligosaccharides (GOS) were conjugated to whey protein isolate (WPI) and sea cucumber peptide (SCP) via the Maillard reaction, achieving a grafting degree of 29 %, then triphenylphosphonium (TPP) was linked by amide reaction. Secondly, AXT was loaded into the complex of SCP-WPI-GOS-TPP (SWGT) to form AXT@SCP-WPI-GOS-TPP(AXT@SWGT) nanoparticles. The Pearson coefficient increased from 0.69 to 0.76 after introducing TPP targeting moiety. In vivo experiments showed that AXT@SWGT significantly alleviated liver injury caused by alcohol. The vacuolation and fat accumulation associated with alcoholic liver injury was alleviated. The alcohol dehydrogenase and aldehyde dehydrogenase activity were improved by 296.88 % and 34.19 %, respectively. AXT@SWGT significantly enhanced the biological activities of glutathione by 76.86 %, catalase by 145.42 %, and superoxide dismutase by 33.48 %, thereby alleviating oxidative stress. The results indicated that the AXT@SWGT might have the potential to intervene alcoholic liver injury via the dual targeting strategy.

Transepithelial transport of nanoparticles in oral drug delivery: From the perspective of surface and holistic property modulation

Despite the promising prospects of nanoparticles in oral drug delivery, the process of oral administration involves a complex transportation pathway that includes cellular uptake, intracellular trafficking, and exocytosis by intestinal epithelial cells, which are necessary steps for nanoparticles to enter the bloodstream and exert therapeutic effects. Current researchers have identified several crucial factors that regulate the interaction between nanoparticles and intestinal epithelial cells, including surface properties such as ligand modification, surface charge, hydrophilicity/hydrophobicity, intestinal protein corona formation, as well as holistic properties like particle size, shape, and rigidity. Understanding these properties is essential for enhancing transepithelial transport efficiency and designing effective oral drug delivery systems. Therefore, this review provides a comprehensive overview of the surface and holistic properties that influence the transepithelial transport of nanoparticles, elucidating the underlying principles governing their impact on transepithelial transport. The review also outlines the chosen of parameters to be considered for the subsequent design of oral drug delivery systems.

Donkey Gelatin and Keratin Nanofibers Loaded with Antioxidant Agents for Wound Healing Dressings

Acute and chronic wounds present a significant healthcare challenge, requiring innovative solutions for effective treatment. The exploitation of natural by-products with advanced cell regeneration potential and plant-based materials, which possess bioactive properties, is an innovative topic in wound management. This study investigates the potential of donkey gelatin and keratin for blending with natural bioactive extracts such as sumac, curcumin, and oak acorn to fabricate antioxidant and antimicrobial nanofibers with accelerated wound healing processes. The fabricated nanofibers possess good in vitro biocompatibility, except for the sumac-based donkey nanofibers, where cell viability significantly dropped to 56.25% (p < 0.05 compared to non-treated cells). The nanofiber dimensions showed structural similarities to human extracellular matrix components, providing an ideal microenvironment for tissue regeneration. The donkey nanofiber-based sumac and curcumin extracts presented a higher dissolution in the first 10 min (74% and 72%). Curcumin extract showed similar antimicrobial and antifungal performances to rivanol, while acorn and sumac extracts demonstrated similar values to each other. In vitro tests performed on murine fibroblast cells demonstrated high migration rates of 89% and 85% after 24 h in the case of acorn and curcumin nanofibers, respectively, underscoring the potential of these nanofibers as versatile platforms for advanced wound care applications.

CD-MOFs: From preparation to drug delivery and therapeutic application

Cyclodextrin metal-organic frameworks (CD-MOFs) show considerable advantages of edibility, degradability, low toxicity, and high drug loading, which have attracted enormous interest, especially in drug delivery. This review summarizes the typical synthesis approaches of CD-MOFs, the drug loading methods, and the mechanism of encapsulation and release. The influence of the structure of CD-MOFs on their drug encapsulation and release is highlighted. Finally, the challenges CD-MOFs face are discussed regarding biosafety assessment systems, stability in aqueous solution, and metal ion effect.

Oral nanomedicine biointeractions in the gastrointestinal tract in health and disease

Oral administration is the preferred route of administration based on the convenience for and compliance of the patient. Oral nanomedicines have been developed to overcome the limitations of free drugs and overcome gastrointestinal (GI) barriers, which are heterogeneous across healthy and diseased populations. This review aims to provide a comprehensive overview and comparison of the oral nanomedicine biointeractions in the gastrointestinal tract (GIT) in health and disease (GI and extra-GI diseases) and highlight emerging strategies that exploit these differences for oral nanomedicine-based treatment. We introduce the key GI barriers related to oral delivery and summarize their pathological changes in various diseases. We discuss nanomedicine biointeractions in the GIT in health by describing the general biointeractions based on the type of oral nanomedicine and advanced biointeractions facilitated by advanced strategies applied in this field. We then discuss nanomedicine biointeractions in different diseases and explore how pathological characteristics have been harnessed to advance the development of oral nanomedicine.

Nanocarriers transport across the gastrointestinal barriers: The contribution to oral bioavailability via blood circulation and lymphatic pathway

Oral administration is the preferred route of drug delivery in clinical practice due to its noninvasiveness, safety, convenience, and high patient compliance. The gastrointestinal tract (GIT) plays a crucial role in facilitating the targeted delivery of oral drugs. However, the GIT presents multiple barriers that impede drug absorption, including the gastric barrier in the stomach and the mucus and epithelial barriers in the intestine. In recent decades, nanotechnology has emerged as a promising approach for overcoming these challenges by utilizing nanocarrier-based drug delivery systems such as liposomes, micelles, polymeric nanoparticles, solid lipid nanoparticles, and inorganic nanoparticles. Encapsulating drugs within nanocarriers not only protects them from degradation but also enhances their transport and absorption across the GIT, ultimately improving oral bioavailability. The aim of this review is to elucidate the mechanisms underlying nanocarrier-mediated transportation across the GIT into systemic circulation via both the blood circulation and lymphatic pathway.

Role of Particle Size in Translational Research of Nanomedicines for Successful Drug Delivery: Discrepancies and Inadequacies

Despite significant research progress in substantiating the therapeutic merits of nanomedicines and the emergence of sophisticated nanotechnologies, the translation of this knowledge into new therapeutic modalities has been sluggish, indicating the need for a more comprehensive understanding of how the unique physicochemical properties of nanoparticles affect their clinical applications. Particle size is a critical quality attribute that impacts the bio-fate of nanoparticles, yet precise knowledge of its effect remains elusive with discrepancies among literature reports. This review aims to address this scientific knowledge gap from a drug development perspective by highlighting potential inadequacies during the evaluation of particle size effects. We begin with a discussion on the major issues in particle size characterization along with the corresponding remedies. The influence of confounding factors on biological effects of particle size, including colloidal stability, polydispersity, and in vitro drug release, are addressed for establishing stronger in vitro-in vivo correlation. Particle size design and tailoring approaches for successful nanoparticulate drug delivery beyond parenteral administration are also illustrated. We believe a holistic understanding of the effect of particle size on bio-fate, combined with consistent nanoparticle manufacturing platforms and tailored characterization techniques, would expedite the translation of nanomedicines into clinical practice.

Oral hydrogel nanoemulsion co-delivery system treats inflammatory bowel disease via anti-inflammatory and promoting intestinal mucosa repair

BACKGROUND

Due to oral nano-delivery systems for the treatment of inflammatory bowel disease (IBD) are often failed to accumulated to the colonic site and could not achieve controlled drug release, it's urgent to develop a microenvironment responsive drug delivery to improve therapy efficacy. Inflammation at the IBD site is mainly mediated by macrophages, which are the key effector cells. Excessive inflammation leads to oxidative stress and intestinal mucosal damage. The use of curcumin (CUR) and emodin (EMO) together for the treatment of IBD is promising due to their respective anti-inflammatory and intestinal mucosal repair effects. In view of the pH gradient environment of gastrointestinal tract, here we prepared pH-responsive sodium alginate (SA) hydrogel-coated nanoemulsions to co-deliver CUR and EMO (CUR/EMO NE@SA) to achieve controlled drug release and specifically target macrophages of the colon.

RESULTS

In this study, a pH-responsive CUR/EMO NE@SA was successfully developed, in which the CUR/EMO NE was loaded by chitosan and further crosslinked with sodium alginate. CUR/EMO NE@SA had a pH-responsive property and could achieve controlled drug release in the colon. The preparation could significantly alleviate and improve the colon inflammatory microenvironment by decreasing TNF-α and IL-6 expression, increasing IL-10 expression, scavenging reactive oxygen species in macrophages, and by ameliorating the restoration of intestinal mucosal tight junction protein expression. Furthermore, we revealed the molecular mechanism of the preparation for IBD treatment, which might due to the CUR and EMO synergic inhibition of NF-κB to improve the pro-inflammatory microenvironment. Our study provides a new IBD therapy strategy via synergically inhibiting inflammatory, repairing mucosal and clearing ROS by pH-sensitive hydrogel-encapsulated nanoemulsion drug delivery system, which might be developed for other chronic inflammatory disease treatment.

CONCLUSIONS

It's suggested that pH-sensitive hydrogel-coated nanoemulsion-based codelivery systems are a promising combinatorial platform in IBD.

A large particle size is required by a nano/micron sized-fluticasone propionate inhalable suspension for asthma treatment

The nano/micron sized-fluticasone propionate inhalable suspension (FPs) is used for asthma treatment, and this study aimed to elucidate the effects of particle size on the absorption of FPs by various pulmonary cells and the subsequent therapeutic efficacy for asthma. FPs of 727, 1136 and 1612 nm were prepared, and an increase in diameter diminished the endocytosis and macropinocytosis of FPs by alveolar epithelial cells (A549 and Calu-3 cells) but facilitated their uptake by M2-like macrophages; results about the transport across Calu-3 monolayer showed the mucus layer was the main rate-limiting step for the uptake of FPs by epithelial cells; the animal tests showed that although a decrease in diameter improved the pulmonary absorption of FPs, the particle size did not affect the lung distribution of FPs; a further detection revealed that larger FPs were taken more effectively by alveolar macrophages and lymphocytes and exerted a better therapeutic effect on asthma than the smaller ones. This study showed that the particle size of FPs had a significant impact on their absorption, elimination and cellular distribution in the lung after inhalation and further on their effectiveness in asthma treatment, and the particle size of the nano/micron sized-FPs should be designed and optimized for asthma treatment on the premise of meeting the requirements of inhalation preparations.

Alginate-based drug carrier systems to target inflammatory bowel disease: A review

Inflammatory bowel disease (IBD) is an inflammatory disorder that affects the gastrointestinal tract. IBD has become an increasingly common condition in both developed and developing nations over the last few decades, owing to a variety of factors like a rising population and diets packed with processed and junk foods. While the root pathophysiology of IBD is unknown, treatments are focused on medications aimed to mitigate symptoms. Alginate (AG), a marine-derived polysaccharide, is extensively studied for its biocompatibility, pH sensitivity, and crosslinking nature. This polymer is thoroughly researched in drug delivery systems for IBD treatment, as it is naturally available, non-toxic, cost effective, and can be easily and safely cross-linked with other polymers to form an interconnected network, which helps in controlling the release of drugs over an extended period. There are various types of drug delivery systems developed from AG to deliver therapeutic agents; among them, nanotechnology-based systems and hydrogels are popular due to their ability to facilitate targeted drug delivery, reduce dosage, and increase the therapeutic efficiency. AG-based carrier systems are not only used for the sustained release of drug, but also used in the delivery of siRNA, interleukins, and stem cells for site directed drug delivery and tissue regenerating ability respectively. This review is focussed on pathogenesis and currently studied medications for IBD, AG-based drug delivery systems and their properties for the alleviation of IBD. Moreover, future challenges are also be discoursed to improve the research of AG in the field of biopharmaceuticals and drug delivery.

Development and In Vitro Analysis of Layer-by-Layer Assembled Membranes for Potential Wound Dressing: Electrospun Curcumin/Gelatin as Middle Layer and Gentamicin/Polyvinyl Alcohol as Outer Layers

Nanofibrous membranes made of hydrogels have high specific surface areas and are suitable as drug carriers. Multilayer membranes fabricated by continuous electrospinning could delay drug release by increasing diffusion pathways, which is beneficial for long-term wound care. In this experiment, polyvinyl alcohol (PVA) and gelatin were used as membrane substrates, and a sandwich PVA/gelatin/PVA structure of layer-by-layer membranes was prepared by electrospinning under different drug loading concentrations and spinning times. The outer layers on both sides were citric-acid-crosslinked PVA membranes loaded with gentamicin as an electrospinning solution, and the middle layer was a curcumin-loaded gelatin membrane for the study of release behavior, antibacterial activity, and biocompatibility. According to the in vitro release results, the multilayer membrane could release curcumin slowly; the release amount was about 55% less than that of the single layer within 4 days. Most of the prepared membranes showed no significant degradation during immersion, and the phosphonate-buffered saline absorption rate of the multilayer membrane was about five to six times its weight. The results of the antibacterial test showed that the multilayer membrane loaded with gentamicin had a good inhibitory effect on Staphylococcus aureus and Escherichia coli. In addition, the layer-by-layer assembled membrane was non-cytotoxic but detrimental to cell attachment at all gentamicin-carrying concentrations. This feature could be used as a wound dressing to reduce secondary damage to the wound when changing the dressing. This multilayer wound dressing could be applied to wounds in the future to reduce the risk of bacterial infection and help wounds heal.

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.

Multifunctional hydrogels based on chitosan, hyaluronic acid and other biological macromolecules for the treatment of inflammatory bowel disease: A review

Hydrogel is a three-dimensional network polymer material rich in water. It is widely used in the biomedical field because of its unique physical and chemical properties and good biocompatibility. In recent years, the incidence of inflammatory bowel disease (IBD) has gradually increased, and the disadvantages caused by traditional drug treatment of IBD have emerged. Therefore, there is an urgent need for new treatments to alleviate IBD. Hydrogel has become a potential therapeutic platform. However, there is a lack of comprehensive review of functional hydrogels for IBD treatment. This paper first summarizes the pathological changes in IBD sites. Then, the action mechanisms of hydrogels prepared from chitosan, sodium alginate, hyaluronic acid, functionalized polyethylene glycol, cellulose, pectin, and γ-polyglutamic acid on IBD were described from aspects of drug delivery, peptide and protein delivery, biologic therapies, loading probiotics, etc. In addition, the advanced functions of IBD treatment hydrogels were summarized, with emphasis on adhesion, synergistic therapy, pH sensitivity, particle size, and temperature sensitivity. Finally, the future development direction of IBD treatment hydrogels has been prospected.

Orally deliverable sequence-targeted astaxanthin nanoparticles for colitis alleviation

Orally targeted strategy of anti-inflammatory agents has attracted tremendous attention for reducing highly health-care costs and enhancing the intervention efficiency of ulcerative colitis (UC). Herein, we developed a new kind of sequence-targeted astaxanthin nanoparticles for UC treatment. Astaxanthin nanoparticles were firstly designed by self-assembly method using (3-carboxypentyl) (triphenyl) phosphonium bromide (TPP)-modified whey protein isolate (WPI)-dextran (DX) conjugates. Subsequently, lipoic acid (LA) modified hyaluronic acid (HA) was coated on the surface of the nanoparticles by double emulsion evaporation method. Exhilaratingly, the constructed sequence-targeted astaxanthin nanoparticle exhibited excellent macrophages and mitochondria targeting ability, with a Pearson's correlation coefficient of 0.84 adstnd 0.92, respectively. In vivo imaging elucidated an obvious accumulation of the sequence-targeted nanoparticles in colon tissues in UC mice. Meanwhile, the reduction stimulus release features of astaxanthin were observed in the presence of 10 mM of glutathione (GSH) at pH 7.4. Most importantly, in vivo experiments indicated that sequence-targeted astaxanthin nanoparticles could markedly alleviate inflammation by moderating the TLR4/MyD88/NF-κB signaling pathway. What's more, the composition of gut microbiota and the production of short chain fatty acid were also improved upon the uptake of sequence-targeted astaxanthin nanoparticles. Our results suggested this novel astaxanthin nanoparticles, which showed sequence-targeted ability and reduction response feature, could be exploited as a promising strategy for effective UC treatment.

Curcumin-based nanotechnology approaches and therapeutics in restoration of autoimmune diseases

Autoimmune diseases usually arise as a result of an aberrant immune system attack on normal tissues of the body, which leads to a cascade of inflammatory reactions. The immune system employs different types of protective and anti-inflammatory cells for the regulation of this process. Curcumin is a known natural anti-inflammatory agent that inhibits pathological autoimmune processes by regulating inflammatory cytokines and their associated signaling pathways in immune cells. Due to the unstable nature of curcumin and its susceptibility to either degradation, or metabolism into other chemical entities (i.e., metabolites), encapsulation of this agent into various nanocarriers would appear to be an appropriate strategy for attaining greater beneficial effects from curcumin as it pertains to immunomodulation. Many studies have focused on the design and development of curcumin nanodelivery systems (micelles, dendrimers, and diverse nanocarriers) and are summarized in this review in order to obtain greater insight into novel drug delivery systems for curcumin and their suitability for the management of autoimmune diseases.

Understanding the Phagocytosis of Particles: the Key for Rational Design of Vaccines and Therapeutics

A robust comprehension of phagocytosis is crucial for understanding its importance in innate immunity. A detailed description of the molecular mechanisms that lead to the uptake and clearance of endogenous and exogenous particles has helped elucidate the role of phagocytosis in health and infectious or autoimmune diseases. Furthermore, knowledge about this cellular process is important for the rational design and development of particulate systems for the administration of vaccines or therapeutics. Depending on these specific applications and the required biological responses, particles must be designed to encourage or avoid their phagocytosis and prolong their circulation time. Functionalization with specific polymers or ligands and changes in the size, shape, or surface of particles have important effects on their recognition and internalization by professional and nonprofessional phagocytes and have a major influence on their fate and safety. Here, we review the phagocytosis of particles intended to be used as carrier or delivery systems for vaccines or therapeutics, the cells involved in this process depending on the route of administration, and the strategies employed to obtain the most desirable particles for each application through the manipulation of their physicochemical characteristics. We also offer a view of the challenges and potential opportunities in the field and give some recommendations that we expect will enable the development of improved approaches for the rational design of these systems.

Nanococktail Based on Supramolecular Glyco-Assembly for Eradicating Tumors In Vivo

The development of robust phototherapeutic strategies for eradicating tumors remains a significant challenge in the transfer of cancer phototherapy to clinical practice. Here, a phototherapeutic nanococktail atovaquone/17-dimethylaminoethylamino-17-demethoxygeldanamycin/glyco-BODIPY (ADB) was developed to enhance photodynamic therapy (PDT) and photothermal therapy (PTT) via alleviation of hypoxia and thermal resistance that was constructed using supramolecular self-assembly of glyco-BODIPY (BODIPY-SS-LAC, BSL-1), hypoxia reliever atovaquone (ATO), and heat shock protein inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG). Benefiting from a glyco-targeting and glutathione (GSH) responsive units BSL-1, ADB can be rapidly taken up by hepatoma cells, furthermore the loaded ATO and 17-DMAG can be released in original form into the cytoplasm. Using in vitro and in vivo results, it was confirmed that ADB enhanced the synergetic PDT and PTT upon irradiation using 685 nm near-infrared light (NIR) under a hypoxic tumor microenvironment where ATO can reduce O₂ consumption and 17-DMAG can down-regulate HSP90. Moreover, ADB exhibited good biosafety, and tumor eradication in vivo. Hence, this as-developed phototherapeutic nanococktail overcomes the substantial obstacles encountered by phototherapy in tumor treatment and offers a promising approach for the eradication of tumors.

Application of chitosan/alginate nanoparticle in oral drug delivery systems: prospects and challenges

Oral drug delivery systems (ODDSs) have various advantages of simple operation and few side effects. ODDSs are highly desirable for colon-targeted therapy (e.g. ulcerative colitis and colorectal cancer), as they improve therapeutic efficiency and reduce systemic toxicity. Chitosan/alginate nanoparticles (CANPs) show strong electrostatic interaction between the carboxyl group of alginates and the amino group of chitosan which leads to shrinkage and gel formation at low pH, thereby protecting the drugs from the gastrointestinal tract (GIT) and aggressive gastric environment. Meanwhile, CANPs as biocompatible polymer, show intestinal mucosal adhesion, which could extend the retention time of drugs on inflammatory sites. Recently, CANPs have attracted increasing interest as colon-targeted oral drug delivery system for intestinal diseases. The purpose of this review is to summarize the application and treatment of CANPs in intestinal diseases and insulin delivery. And then provide a future perspective of the potential and development direction of CANPs as colon-targeted ODDSs.

Distribution and translocation of micro- and nanoplastics in fish

Microplastics (MPs) and nanoplastics (NPs) are regarded as emerging particulate contaminants. Here, we first summarize the distribution of plastic particles in fish. Field investigations verify the presence of various kinds of fibrous, spherical, and fragmentary MPs in fish gastrointestinal tract and gills, and specifically in muscle and liver. Laboratory works demonstrate that NPs even penetrate into blood vessels of fish and pass onto next generations. Second, we systematically discuss the translocation ability of MPs and NPs in fish. MPs can enter early-developing fish through adherence, and enter adult fish internal organs by intestine absorption or epidermis infiltration. NPs can not only penetrate into fish embryo blastopores, but also reach adult fish internal organs through blood circulation. Third, the cellular basis for translocation of plastic particles, NPs in particular, into cells are critically reviewed. Endocytosis and paracellular penetration are two main pathways for them to enter cells and intercellular space, respectively. Finally, we compare the chemical and physical properties among various particular pollutants (MPs, NPs, settleable particulate matters, and manufactured nanomaterials) and their translocation processes at different biological levels. In future studies, it is urgent to break through the bottleneck techniques for NPs quantification in field environmental matrix and organisms, re-confirm the existence of MPs and NPs in field organisms, and develop more detailed translocating mechanisms of MPs and NPs by applying cutting-edge tracking techniques.

Preparation of MSZ Hydrogel and Its Treatment of Colitis

In order to control the release of mesalazine (MSZ) in the gastrointestinal tract to achieve better pharmacological effects in the colon, in this study, MSZ was added to hydroxypropyl-β-cyclodextrin (HP-β-CD) to form a water-soluble HP-β-CD/MSZ inclusion complex. Then, the inclusion compound was loaded into the structure of the bilayer polyelectrolyte complex microsphere formed by alginate (Alg), chitosan (Cs), and kappa carrageenan (κ-Car) as the hydrogel carrier, and the hydrogel beads with colon-specific release MSZ after oral administration were formed. The formed hydrogel beads have different swelling capabilities in different pH media and have the greatest swelling degree under pH 7.4. The encapsulation efficiency and drug loading of hydrogel beads can reach up to 83.23 and 18.31%, respectively, and the size of hydrogel beads can be reduced to less than 1 mm after drying, so that the size of oral administration can be reached. In vivo experiments also showed that the formed hydrogel beads had a better therapeutic effect on colitis than free drugs, and the microspheres were biodegradable, so the double-layer pH-sensitive microspheres could be effectively used in colon-targeting drug delivery.

Drug delivery to the inflamed intestinal mucosa - targeting technologies and human cell culture models for better therapies of IBD

Current treatment strategies for inflammatory bowel disease (IBD) seek to alleviate the undesirable symptoms of the disorder. Despite the higher specificity of newer generation therapeutics, e.g. monoclonal antibodies, adverse effects still arise from their interference with non-specific systemic immune cascades. To circumvent such undesirable effects, both conventional and newer therapeutic options can benefit from various targeting strategies. Of course, both the development and the assessment of the efficiency of such targeted delivery systems necessitate the use of suitable in vivo and in vitro models representing relevant pathophysiological manifestations of the disorder. Accordingly, the current review seeks to provide a comprehensive discussion of the available preclinical models with emphasis on human in vitro models of IBD, along with their potentials and limitations. This is followed by an elaboration on the advancements in the field of biology- and nanotechnology-based targeted drug delivery systems and the potential rooms for improvement to facilitate their clinical translation.

Construction of Chitosan/Alginate Nano-Drug Delivery System for Improving Dextran Sodium Sulfate-Induced Colitis in Mice

(1) Background: In the treatment of ulcerative colitis (UC), accurate delivery and release of anti-inflammatory drugs to the site of inflammation can reduce systemic side effects. (2) Methods: We took advantage of this goal to prepare resveratrol-loaded PLGA nanoparticles (RES-PCAC-NPs) by emulsification solvent volatilization. After layer-by-layer self-assembly technology, we deposited chitosan and alginate to form a three-layer polyelectrolyte film. (3) Results: It can transport nanoparticles through the gastric environment to target inflammation sites and slowly release drugs at a specific pH. The resulting RES-PCAC-NPs have an ideal average diameter (~255 nm), a narrow particle size distribution and a positively charged surface charge (~13.5 mV). The Fourier transform infrared spectroscopy showed that resveratrol was successfully encapsulated into PCAC nanoparticles, and the encapsulation efficiency reached 87.26%. In addition, fluorescence imaging showed that RES-PCAC-NPs with positive charges on the surface can effectively target and accumulate in the inflammation site while continuing to penetrate downward to promote mucosal healing. Importantly, oral RES-PCAC-NPs treatment in DSS-induced mice was superior to other results in significantly improved inflammatory markers of UC. (4) Conclusions: Our results strongly prove that RES-PCAC-NPs can target the inflamed colon for maximum efficacy, and this oral pharmaceutical formulation can represent a promising formulation in the treatment of UC.

Quadruple-responsive nanoparticle-mediated targeted combination chemotherapy for metastatic breast cancer

The synergism of combination chemotherapy can only be achieved under specific drug ratios. Herein, hyaluronic acid (HA)-functionalized regenerated silk fibroin-based nanoparticles (NPs) were used to concurrently deliver curcumin (CUR) and 5-fluorouracil (5-FU) at various weight ratios (3.3 : 1, 1.6 : 1, 1.1 : 1, 1 : 1, and 1 : 1.2) to breast tumor cells. The generated HA-CUR/5-FU-NPs were found to have desirable particle sizes (around 200 nm), narrow size distributions, and negative zeta potentials (about -26.0 mV). Interestingly, these NPs showed accelerated drug release rates when they were exposed to buffers that mimicked the multi-hallmarks in the tumor microenvironment (pH/hydrogen peroxide/glutathione/hyaluronidase). The surface functionalization of NPs with HA endowed them with in vitro and in vivo breast tumor-targeting properties. Furthermore, we found that the co-loading of CUR and 5-FU in HA-functionalized NPs exhibited obvious synergistic anti-cancer, pro-apoptotic, and anti-migration effects, and the strongest synergism was found at the CUR/5-FU weight ratio of 1 : 1.2. Most importantly, mice experiments revealed that HA-CUR/5-FU-NPs (1 : 1.2) showed a superior anti-cancer activity against metastatic breast cancer compared to the single drug-loaded NPs and non-functionalized CUR/5-FU-NPs (1 : 1.2). Collectively, these results demonstrate that HA-CUR/5-FU-NPs (1 : 1.2) can be exploited as a robust nanococktail for the treatment of breast cancer and its lung metastasis.

Engineered Nanomaterials: The Challenges and Opportunities for Nanomedicines

The emergence of nanotechnology as a key enabling technology over the past years has opened avenues for new and innovative applications in nanomedicine. From the business aspect, the nanomedicine market was estimated to worth USD 293.1 billion by 2022 with a perception of market growth to USD 350.8 billion in 2025. Despite these opportunities, the underlying challenges for the future of engineered nanomaterials (ENMs) in nanomedicine research became a significant obstacle in bringing ENMs into clinical stages. These challenges include the capability to design bias-free methods in evaluating ENMs' toxicity due to the lack of suitable detection and inconsistent characterization techniques. Therefore, in this literature review, the state-of-the-art of engineered nanomaterials in nanomedicine, their toxicology issues, the working framework in developing a toxicology benchmark and technical characterization techniques in determining the toxicity of ENMs from the reported literature are explored.