Oral delivery of folate-targeted resveratrol-loaded nanoparticles for inflammatory bowel disease therapy in rats

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

An exosomal approach for oral delivery of resveratrol: Implications for inflammatory bowel disease treatment in rat model

AIMS

Resveratrol (RSV) is a polyphenolic substance found in numerous natural products. Despite the wide range of therapeutic activities, including antioxidant and anti-inflammatory effects, the poor pharmacokinetic characteristics decrease the RSV bioavailability following oral administration. Milk-derived exosomes (MEXOs), as a class of natural nanocarriers, are promising candidates for oral drug delivery approaches.

MAIN METHODS

The current study developed RSV-loaded MEXOs to enhance the RSV oral bioavailability, introducing a suitable exosomal formulation for suppressing colon inflammation in acetic acid-induced rat models.

KEY FINDINGS

The results showed a remarkable encapsulation efficiency of 83.33 %. The in vitro release profile demonstrated a good retaining capability in acidic conditions (pH 1.2) and a considerable release in a simulated duodenal environment (pH 6.8). According to the permeability study, encapsulation of RSV improved its transportation across the Caco-2 monolayer. Moreover, the in vivo and histological analysis results proved that the RSV-MEXOs formulation successfully alleviates the inflammation in colitis rat models and effectively relieves the colitis.

SIGNIFICANCE

Our findings suggest that MEXOs should be of great attention as promising oral drug delivery vehicles for further clinical evaluations.

Synthesis of folate targeted theranostic cubosomal platform for co-delivery of bismuth oxide and doxorubicin to melanoma in vitro and in vivo

Liquid crystalline nanoparticles (LCNPs) have gained much attention in cancer nanomedicines due to their unique features such as high surface area, storage stability, and sustained-release profile. In the current study, a novel LCNP for co-encapsulation of Bi2O3 and hydrophilic doxorubicin (DOX) was fabricated and functionalized with folic acid (FA) to achieve efficient tumor targeting toward CT-scan imaging and chemotherapy of melanoma in vitro and in vivo. LCNPs Bi2O3 NPs were prepared using glycerol monooleate-pluronic F-127 (GMO/PF127/water). Firstly, GMO/water were homogenized to prepare LC gel. Then, the stabilizer aqueous solution (PF127/Bi2O3/DOX) was added to the prepared LC gel and homogenized using homogenization and ultrasonication. The formulated NPs exhibited superior stability with encapsulation efficiency. High cytotoxicity and cellular internalization of the FA-Bi2O3-DOX-NPs were observed in comparison with Bi2O3-DOX-NPs and the free DOX in folate-receptor (FR) overexpressing cells (B16F10) in vitro. Moreover, ideal tumor suppression with increased survival rate were observed in tumorized mice treated with FA-Bi2O3-DOX-NPs compared to those treated with non-targeted one. On the other hand, the CT-imaging ability of the Bi2O3-DOX-NPs was tested inB16F10 tumor-bearing mice. The obtained data indicated a high potential of the developed targeted theranostic FA-Bi2O3-DOX-NPs for diagnostics and treatment of melanoma.

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

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

Research Progress on Immunomodulatory Effects of Poly (Lactic-co- Glycolic Acid) Nanoparticles Loaded with Traditional Chinese Medicine Monomers

Immunomodulatory mechanisms are indispensable and key factors in maintaining the balance of the environment in humans. When the immune function of the immune system is impaired, autoimmune diseases occur. Excessive body fatigue, natural aging of the human body, malnutrition, genetic factors and other reasons cause low immune function, due to which the body is prone to being infected by bacteria or cancer. Clinically, the existing therapeutic drugs still have problems such as high toxicity, long treatment cycle, drug resistance and high price, so we still need to explore and develop a high efficiency and low toxicity drug. Poly(lactic-co-glycolic acid) (PLGA) refers to a nontoxic polymer compound that exhibits excellent biocompatibility. Traditional Chinese medicine (TCM) monomers come from natural plants, and have the characteristics of high efficiency and low toxicity. Applying PLGA to TCM monomers can make up for the defects of traditional dosage forms, improve bioavailability, reduce the frequency and dosage of drug use, and reduce toxicity and side effects, thus having the characteristics of sustained release and targeting. Accordingly, PLGA nanoparticles loaded with TCM monomers have been the focus of development. The previous research on drug loading advantages, preparation methods, and immune regulation of TCM PLGA nanoparticles is summarized in the following sections.

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.

Recent advances in oral delivery systems of resveratrol: foreseeing their use in functional foods

Herein, we review the current state-of-the-art on the use of micro- and nano-delivery systems, a possible solution to some of the drawbacks associated with the incorporation of resveratrol in foods. Specifically, we present an overview of a wide range of micro-nanostructures, namely, lipidic and polymeric, used for the delivery of resveratrol. Also, the gastrointestinal fate of resveratrol-loaded micro-nanostructures, as a critical parameter for their use as functional food, is explored in terms of stability, bioaccessibility, and bioavailability. Different micro-nanostructures are of interest for the development of functional foods given that they can provide different advantages and properties to these foods and even be tailor-made to address specific issues (e.g., controlled or targeted release). Therefore, we discuss a wide range of micro-nanostructures, namely, lipidic and polymeric, used to deliver resveratrol and aimed at the development of functional foods. It has been reported that the use of some production methodologies can be of greater interest than others, for example, emulsification, solvent displacement and electrohydrodynamic processing (EHDP) enable a greater increase in bioaccessibility. Additionally, the use of coatings facilitates further improvements in bioaccessibility, which is likely due to the increased gastric stability of the coated micro-nanostructures. Other properties, such as mucoadhesion, can also help improve bioaccessibility due to the increase in gut retention time. Additionally, cytotoxicity (e.g., biocompatibility, antioxidant, and anti-inflammatory) and possible sensorial impact of resveratrol-loaded micro- and nano-systems in foods are highlighted.

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

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

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

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

Designing a microbial fermentation-functionalized alginate microsphere for targeted release of 5-ASA using nano dietary fiber carrier for inflammatory bowel disease treatment

Patients with inflammatory bowel disease (IBD) always suffer from severe abdominal pain and appear to be at high risk for colorectal cancer. Recently, the co-delivery of targeted drugs and gut microbiota has developed into an attractive strategy. A new strategy using gut microbiota fermentation to overcome the interspace diffuse resistance from the mucus layer to control drug release in inflammatory bowel sites (IBS sites) has not yet been available. Here, we designed an alginate hydrogel microsphere encapsulating bifidobacterium (Bac) and drug-modified nanoscale dietary fibers (NDFs). The hydrogel microsphere is responsible for protecting drugs from acidic and multi-enzymatic environments and delivering drugs to the colorectum. Subsequently, the fermentation of Bac by digesting NDFs and proteins as carbon and nitrogen sources can promote drug release and play a probiotic role in the gut microbiota. In vitro evidence indicated that small-sized NDF (NDF-1) could significantly promote short-chain fatty acid (SCFA) expression. Notably, NDF-1 hydrogel microspheres showed a boost release of 5-ASA in the IBS sites, resulting in the amelioration of gut inflammation and remodeling of gut microbiota in chronic colitis mice. This study developed a controlled release system based on microbial fermentation for the treatment of IBD.

Dual pH and microbial-sensitive galactosylated polymeric nanocargoes for multi-level targeting to combat ulcerative colitis

Ulcerative colitis (UC) is a type of inflammatory bowel disease characterized by inflammation, ulcers and irritation of the mucosal lining. Oral drug delivery in UC encounters challenges because of multifaceted barriers. Dexamethasone-loaded galactosylated-PLGA/Eudragit S100/pullulan nanocargoes (Dexa-GP/ES/Pu NCs) have been developed with a dual stimuli-sensitive coating responsive to both colonic pH and microbiota, and an underneath galactosylated-PLGA core (GP). The galactose ligand of the GP preferentially binds to the macrophage galactose type-lectin-C (MGL-2) surface receptor. Therefore, both stimuli and ligand-mediated targeting facilitate nanocargoes to deliver Dexa specifically to the colon with enhanced macrophage uptake. Modified emulsion method coupled with a solvent evaporation coating technique was employed to prepare Dexa-GP/ES/Pu NCs. The nanocargoes were tested using in vitro, ex vivo techniques and dextran sodium sulfate (DSS) induced UC model. Prepared nanocargoes had desired physicochemical properties, drug release, cell uptake and cellular viability. Investigations using a DSS-colitis model showed high localization and mitigation of colitis with downregulation of NF-ĸB and COX-2, and restoration of clinical, histopathological, biochemical indices, antioxidant balance, microbial alterations, FTIR spectra, and epithelial junctions' integrity. Thus, Dexa-GP/ES/Pu NCs found to be biocompatible nanocargoes capable of delivering drugs to the inflamed colon with unique targeting properties for prolonged duration.

The crossroad of nanovesicles and oral delivery of insulin

INTRODUCTION

Diabetes mellitus is one of the challenging health problems worldwide. Multiple daily subcutaneous injection of insulin causes poor compliance in patients. Development of efficient oral formulations to improve the quality of life of such patients has been an important goal in pharmaceutical industry. However, due to serious issues such as low bioavailability and instability, it has not been achieved yet.

AREAS COVERED

Due to functional properties of the vesicles and the fact that hepatic-directed vesicles of insulin could reach the clinical phases, we focused on three main vesicular delivery systems for oral delivery of insulin: liposomes, niosomes, and polymersomes. Recent papers were thoroughly discussed to provide a broad overview of such oral delivery systems.

EXPERT OPINION

Although conventional liposomes are unstable in the presence of bile salts, their further modifications such as surface coating could increase their stability in the GI tract. Bilosomes showed good flexibility and stability in GI fluids. Also, niosomes were stable, but they could not induce significant hypoglycemia in animal studies. Although polymersomes were effective, they are expensive and there are some issues about their safety and industrial scale-up. Also, we believe that other modifications such as addition of a targeting agent or surface coating of the vesicles could significantly increase the bioavailability of insulin-loaded vesicles.

More Than Pigments: The Potential of Astaxanthin and Bacterioruberin-Based Nanomedicines

Carotenoids are natural products regulated by the food sector, currently used as feed dyes and as antioxidants in dietary supplements and composing functional foods for human consumption. Of the nearly one thousand carotenoids described to date, only retinoids, derived from beta carotene, have the status of a drug and are regulated by the pharmaceutical sector. In this review, we address a novel field: the transformation of xanthophylls, particularly the highly marketed astaxanthin and the practically unknown bacterioruberin, in therapeutic agents by altering their pharmacokinetics, biodistribution, and pharmacodynamics through their formulation as nanomedicines. The antioxidant activity of xanthophylls is mediated by routes different from those of the classical oral anti-inflammatory drugs such as corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs): remarkably, xanthophylls lack therapeutic activity but also lack toxicity. Formulated as nanomedicines, xanthophylls gain therapeutic activity by mechanisms other than increased bioavailability. Loaded into ad hoc tailored nanoparticles to protect their structure throughout storage and during gastrointestinal transit or skin penetration, xanthophylls can be targeted and delivered to selected inflamed cell groups, achieving a massive intracellular concentration after endocytosis of small doses of formulation. Most first reports showing the activities of oral and topical anti-inflammatory xanthophyll-based nanomedicines against chronic diseases such as inflammatory bowel disease, psoriasis, atopic dermatitis, and dry eye disease emerged between 2020 and 2023. Here we discuss in detail their preclinical performance, mostly targeted vesicular and polymeric nanoparticles, on cellular models and in vivo. The results, although preliminary, are auspicious enough to speculate upon their potential use for oral or topical administration in the treatment of chronic inflammatory diseases.

Advances in Oral Drug Delivery Systems: Challenges and Opportunities

The oral route is the most preferred route for systemic and local drug delivery. However, the oral drug delivery system faces the harsh physiological and physicochemical environment of the gastrointestinal tract, which limits the bioavailability and targeted design of oral drug delivery system. Innovative pharmaceutical approaches including nanoparticulate formulations, biomimetic drug formulations, and microfabricated devices have been explored to optimize drug targeting and bioavailability. In this review, the anatomical factors, biochemical factors, and physiology factors that influence delivering drug via oral route are discussed and recent advance in conventional and novel oral drug delivery approaches for improving drug bioavailability and targeting ability are highlighted. We also address the challenges and opportunities of oral drug delivery systems in future.

ROS-triggered self-disintegrating and pH-responsive astaxanthin nanoparticles for regulating the intestinal barrier and colitis

Smart delivery systems with stimuli-responsive capability are able to improve the bioaccessibility through increasing the solubility, physicochemical stability and biocompatibility of bioactive compounds. In this study, the astaxanthin nanoparticles with reactive oxygen species (ROS) and pH dual-response function were design and constructed using poly (propylene sulfide) covalently modified sodium alginate as carriers based on ultrasonic assisted self-assembly strategy. Atomic force microscope and scanning electron microscope analysis showed that the nanoparticles were spherical in shape with a size of around 260 nm. Meanwhile, the astaxanthin nanoparticles showed both pH and ROS stimuli-responsive release characteristics. In vitro cell experiments showed that astaxanthin nanoparticles significantly inhibited the production of ROS and mitochondrial depolarization induced by oxidative stress. In vivo colitis experiment of mice revealed that astaxanthin nanoparticles could significantly relieve colitis, protect the integrity of colon tissue and restore the expression of tight junction proteins ZO-1 and occludin. The abundance of Lactobacillus and Lachnospiraceae, and the ratio of Firmicutes/Bacteroidota of gut microbiota were significantly improved after intervention of the stimuli-responsive astaxanthin nanoparticles. This work provided a simple strategy for constructing ROS/pH dual response delivery system, which provided an experimental basis for improving the oral bioavailability of hydrophobic active compounds.

Medicinal plant-based drug delivery system for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic recurrent intestinal disease. The incidence rate of IBD is increasing year by year, which seriously endangers human health worldwide. More and more studies have shown that medicinal plants or their main phytochemicals have great potential in the treatment of intestinal diseases. However, the disadvantages of low oral absorption rate, low biological distribution and low systemic bioavailability limit their clinical application to a certain extent. In recent years, the application of nanotechnology has made it possible to treat IBD. Nanoparticles (NPs) drug delivery system has attracted special attention in the treatment of IBD due to its small size, low immunogenicity, surface modification diversity, targeting and other advantages. Synthetic nanoparticles and extracellular vehicles (EVs) can deliver drug components to colon, and play a role in anti-inflammation, regulation of oxidative stress, improvement of intestinal flora, etc. In addition, some medicinal plants can secrete EVs by themselves, and carry biological molecules with therapeutic effects to act on the intestine. Some clinical trials to evaluate the safety, tolerance, toxicity and effectiveness of EVs-loaded drugs in IBD are also progressing steadily. This review introduces that synthetic nanoparticles and medicinal plants derived EVs can play an important role in the treatment of IBD by carrying the effective active phytochemicals of medicinal plants, and discuss the limitations of current research and future research needs, providing a scientific and reliable basis and perspective for further clinical application and promotion.

Emerging Nanotechnologies and Microbiome Engineering for the Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is characterized by the chronic inflammation of the gastrointestinal tract and impacts almost 7 million people across the globe. Current therapeutics are effective in treating the symptoms, but they often do not address the root cause or selectively target areas of inflammation. Notably, self-assembled nanoparticles show great promise as drug delivery systems for the treatment of IBD. Nanoparticles can be designed to survive the harsh gastric conditions and reach inflamed areas of the gastrointestinal tract. Oral drug delivery with nanoparticles can localize drugs to the impacted inflamed region using active and/or passive targeting and promote a high rate of drug dispersion in local tissues, thus reducing potential off-target toxicities. Since a dysregulated gut microbiome is implicated in the development and progression of IBD, it is also important to develop nanoparticles and biomaterials that can restore symbiotic microbes while reducing the proliferation of harmful microbes. In this review, we highlight recent advances in self-assembled nanosystems designed for addressing inflammation and dysregulated gut microbiomes as potential treatments for IBD. Nanoparticles have a promising future in improving the delivery of current therapeutics, increasing patient compliance by providing an oral method of medication, and reducing side effects. However, remaining challenges include scale-up synthesis of nanoparticles, potential side effects, and financial obstacles of clinical trials. It would be in the patients' best interest to continue research on nanoparticles in the pursuit of more effective therapeutics for the treatment of IBD.

Targeting pathophysiological changes using biomaterials-based drug delivery systems: A key to managing inflammatory bowel disease

Inflammatory bowel disease (IBD) is a gastrointestinal disorder, affecting about several million people worldwide. Current treatments fail to adequately control some clinical symptoms in IBD patients, which can adversely impact the patient's quality of life. Hence, the development of new treatments for IBD is needed. Due to their unique properties such as biocompatibility and sustained release of a drug, biomaterials-based drug delivery systems can be regarded as promising candidates for IBD treatment. It is noteworthy that considering the pathophysiological changes occurred in the gastrointestinal tract of IBD patients, especially changes in pH, surface charge, the concentration of reactive oxygen species, and the expression of some biomolecules at the inflamed colon, can help in the rational design of biomaterials-based drug delivery systems for efficient management of IBD. Here, we discuss about targeting these pathophysiological changes using biomaterials-based drug delivery systems, which can provide important clues to establish a strategic roadmap for future studies.

Demystifying phytoconstituent-derived nanomedicines in their immunoregulatory and therapeutic roles in inflammatory diseases

In the past decades, phytoconstituents have appeared as critical mediators for immune regulations among various diseases, both in eukaryotes and prokaryotes. These bioactive molecules, showing a broad range of biological functions, would hold tremendous promise for developing new therapeutics. The discovery of phytoconstituents' capability of functionally regulating immune cells and associating cytokines, suppressing systemic inflammation, and remodeling immunity have rapidly promoted the idea of their employment as anti-inflammatory agents. In this review, we discuss various roles of phyto-derived medicines in the field of inflammatory diseases, including chronic inflammation, autoimmune diseases, and acute inflammatory disease such as COVID-19. Nevertheless, traditional phyto-derived medicines often concurred with their clinical administration limitations, such as their lack of cell specificity, inefficient cytoplasmic delivery, and rapid clearance by the immune system. As alternatives, phyto-derived nano-approaches may provide significant benefits. Both unmodified and engineered nanocarriers present the potential to serve as phytoconstituent delivery systems to improve therapeutic physio-chemical properties and pharmacokinetic profiles. Thus, the development of phytoconstituents' nano-delivery designs, their new and perspective approaches for therapeutical applications are elaborated herein.

Inflammatory auto-immune diseases of the intestine and their management by natural bioactive compounds

Autoimmune diseases are caused by the overactivity of the immune system towards self-constituents. Risk factors of autoimmune diseases are multiple and include genetic, epigenetic, environmental, and psychological. Autoimmune chronic inflammatory bowel diseases, including celiac and inflammatory diseases (Crohn's disease and ulcerative colitis), constitute a significant health problem worldwide. Besides the complexity of the symptoms of these diseases, their treatments have only been palliative. Numerous investigations showed that natural phytochemicals could be promising strategies to fight against these autoimmune diseases. In this respect, plant-derived natural compounds such as flavonoids, phenolic acids, and terpenoids exhibited significant effects against three autoimmune diseases affecting the intestine, particularly bowel diseases. This review focuses on the role of natural compounds obtained from medicinal plants in modulating inflammatory auto-immune diseases of the intestine. It covers the most recent literature related to the effect of these natural compounds in the treatment and prevention of auto-immune diseases of the intestine.

Resveratrol and resveratrol nano-delivery systems in the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic disorder associated with the inflammation in the digestive tract. The exact cause of IBD is unknown; nevertheless, in IBD, the homeostasis of key regulatory factors involved in intestinal immunity has been documented to be disrupted. Despite the lack of a viable treatment for IBD, synthetic drugs and monoclonal antibodies are currently used to treat it. However, these treatments have side effects, and the high relapse rate limits their usage. Dietary polyphenols constitute a great variety of compounds and have shown an array of biological properties. Resveratrol is a natural polyphenol found in grapevines and berries. The therapeutic ability of resveratrol against IBD is amply demonstrated in many in vivo studies. Resveratrol can interact with several molecular targets (Nf-kB, SIRT1, mTOR, HIF-1α, miRNAs, and TNF-α) and effectively prevent/ alleviate IBD symptoms with promising results. Although resveratrol has profound anti-inflammatory properties against IBD, its therapeutic employment is limited due to its low water solubility, less chemical stability, less bioavailability, and rapid metabolism in vivo. Hence, resveratrol encapsulation using different carries and its controlled release has become a promising strategy to overcome limitations. Herein, we meticulously review, talk-over the anti-inflammatory effect and mechanisms of resveratrol in IBD. We further provide the latest information on resveratrol formulations and nano-delivery systems used in oral delivery of resveratrol for the treatment of IBD and offer our view on future research on resveratrol in IBD treatment.

Novel drug delivery systems for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic illness characterized by relapsing inflammation of the intestines. The disorder is stratified according to the severity and is marked by its two main phenotypical representations: Ulcerative colitis and Crohn’s disease. Pathogenesis of the disease is ambiguous and is expected to have interactivity between genetic disposition, environmental factors such as bacterial agents, and dysregulated immune response. Treatment for IBD aims to reduce symptom extent and severity and halt disease progression. The mainstay drugs have been 5-aminosalicylates (5-ASAs), corticosteroids, and immunosuppressive agents. Parenteral, oral and rectal routes are the conventional methods of drug delivery, and among all, oral administration is most widely adopted. However, problems of systematic drug reactions and low specificity in delivering drugs to the inflamed sites have emerged with these regular routes of delivery. Novel drug delivery systems have been introduced to overcome several therapeutic obstacles and for localized drug delivery to target tissues. Enteric-coated microneedle pills, various nano-drug delivery techniques, prodrug systems, lipid-based vesicular systems, hybrid drug delivery systems, and biologic drug delivery systems constitute some of these novel methods. Microneedles are painless, they dislodge their content at the affected site, and their release can be prolonged. Recombinant bacteria such as genetically engineered Lactococcus Lactis and eukaryotic cells, including GM immune cells and red blood cells as nanoparticle carriers, can be plausible delivery methods when evaluating biologic systems. Nano-particle drug delivery systems consisting of various techniques are also employed as nanoparticles can penetrate through inflamed regions and adhere to the thick mucus of the diseased site. Prodrug systems such as 5-ASAs formulations or their derivatives are effective in reducing colonic damage. Liposomes can be modified with both hydrophilic and lipophilic particles and act as lipid-based vesicular systems, while hybrid drug delivery systems containing an internal nanoparticle section for loading drugs are potential routes too. Leukosomes are also considered as possible carrier systems, and results from mouse models have revealed that they control anti- and pro-inflammatory molecules.

Tunneling Nanotubes: A New Target for Nanomedicine?

Tunneling nanotubes (TNTs), discovered in 2004, are thin, long protrusions between cells utilized for intercellular transfer and communication. These newly discovered structures have been demonstrated to play a crucial role in homeostasis, but also in the spreading of diseases, infections, and metastases. Gaining much interest in the medical research field, TNTs have been shown to transport nanomedicines (NMeds) between cells. NMeds have been studied thanks to their advantageous features in terms of reduced toxicity of drugs, enhanced solubility, protection of the payload, prolonged release, and more interestingly, cell-targeted delivery. Nevertheless, their transfer between cells via TNTs makes their true fate unknown. If better understood, TNTs could help control NMed delivery. In fact, TNTs can represent the possibility both to improve the biodistribution of NMeds throughout a diseased tissue by increasing their formation, or to minimize their formation to block the transfer of dangerous material. To date, few studies have investigated the interaction between NMeds and TNTs. In this work, we will explain what TNTs are and how they form and then review what has been published regarding their potential use in nanomedicine research. We will highlight possible future approaches to better exploit TNT intercellular communication in the field of nanomedicine.

Active Targeted Nanoformulations via Folate Receptors: State of the Art and Future Perspectives

In normal tissues, the expression of folate receptors is low and limited to cells that are important for embryonic development or for folate reabsorption. However, in several pathological conditions some cells, such as cancer cells and activated macrophages, overexpress folate receptors (FRs). This overexpression makes them a potential therapeutic target in the treatment of cancer and inflammatory diseases to obtain a selective delivery of drugs at altered cells level, and thus to improve the therapeutic efficacy and decrease the systemic toxicity of the pharmacological treatments. Two strategies have been used to achieve this folate receptor targeting: (i) the use of ligands with high affinity to FRs (e.g., folic acid or anti-FRs monoclonal antibodies) linked to the therapeutic agents or (ii) the use of nanocarriers whose surface is decorated with these ligands and in which the drug is encapsulated. This manuscript analyzes the use of FRs as a target to develop new therapeutic tools in the treatment of cancer and inflammatory diseases with an emphasis on the nanoformulations that have been developed for both therapeutic and imaging purposes.

Preparation of Oral Core-Shell Zein Nanoparticles to Improve the Bioavailability of Glycyrrhizic Acid for the Treatment of Ulcerative Colitis

In this study, oral colon-targeted adhesion core-shell nanoparticles were designed by applying FA-Zein as the core and using pectin as the shell to enhance the low bioavailability exhibited by glycyrrhizic acid (GA) and the anti-inflammatory effect in specific parts of the intestine. As indicated by the results, the nanoparticles (NPs) remained stable in the stomach and small intestine, while pectins began to degrade and release GA in considerable amounts in the colon with the abundant flora. Subsequently, folate-acid targeting was further assessed with Raw 264.7 and NCM 460 cells. Lastly, NPs were reported to exhibit high adhesion on the colon by using the DSS-induced ulcerative colitis mouse model. Moreover, as indicated by in vitro and in vivo studies, nanoparticles could decrease the levels of MPO and TNF-α by reducing macrophages and neutrophils. In brief, this study provides an ideal loaded natural anti-inflammatory drug delivery system to treat ulcerative colitis.

N-trimethyl chitosan coated nano-complexes enhance the oral bioavailability and chemotherapeutic effects of gemcitabine

N-trimethyl chitosan (TMC) is a multifunctional polymer that can be used in various nanoparticle forms in the pharmaceutical, nutraceutical and biomedical fields. In this study, TMC was used as a mucoadhesive adjuvant to enhance the oral bioavailability and hence antitumour effects of gemcitabine formulated into nanocomplexes composed of poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) conjugated with d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). A central composite design was applied to achieve the optimal formulation. Cellular uptake and drug transportation studies revealed the nanocomplexes permeate over the intestinal cells via adsorptive-mediated and caveolae-mediated endocytosis. Pharmacokinetic studies demonstrated the oral drug bioavailability of the nanocomplexes was increased 5.1-fold compared with drug solution. In pharmacodynamic studies, the formulation reduced tumour size 3.1-fold compared with the drug solution. The data demonstrates that TMC modified nanocomplexes can enhance gemcitabine oral bioavailability and promote the anticancer efficacy.

Hyaluronic acid-based nanoplatforms for Doxorubicin: A review of stimuli-responsive carriers, co-delivery and resistance suppression

An important motivation for the use of nanomaterials and nanoarchitectures in cancer therapy emanates from the widespread emergence of drug resistance. Although doxorubicin (DOX) induces cell cycle arrest and DNA damage by suppressing topoisomerase activity, resistance to DOX has severely restricted its anti-cancer potential. Hyaluronic acid (HA) has been extensively utilized for synthesizing nanoparticles as it interacts with CD44 expressed on the surface of cancer cells. Cancer cells can take up HA-modified nanoparticles through receptor-mediated endocytosis. Various types of nanostructures such as carbon nanomaterials, lipid nanoparticles and polymeric nanocarriers have been modified with HA to enhance the delivery of DOX to cancer cells. Hyaluronic acid-based advanced materials provide a platform for the co-delivery of genes and drugs along with DOX to enhance the efficacy of anti-cancer therapy and overcome chemoresistance. In the present review, the potential methods and application of HA-modified nanostructures for DOX delivery in anti-cancer therapy are discussed.

Oral delivery of natural active small molecules by polymeric nanoparticles for the treatment of inflammatory bowel diseases

The incidence of inflammatory bowel disease (IBD) is rapidly rising throughout the world. Although tremendous efforts have been made, limited therapeutics are available for IBD management. Natural active small molecules (NASMs), which are a gift of nature to humanity, have been widely used in the prevention and alleviation of IBD; they have numerous advantageous features, including excellent biocompatibility, pharmacological activity, and mass production potential. Oral route is the most common and acceptable approach for drug administration, but the clinical application of NASMs in IBD treatment via oral route has been seriously restricted by their inherent limitations such as high hydrophobicity, instability, and poor bioavailability. With the development of nanotechnology, polymeric nanoparticles (NPs) have provided a promising platform that can efficiently encapsulate versatile NASMs, overcome multiple drug delivery barriers, and orally deliver the loaded NASMs to targeted tissues or cells while enhancing their stability and bioavailability. Thus, NPs can enhance the preventive and therapeutic effects of NASMs against IBD. Herein, we summarize the recent knowledge about polymeric matrix-based carriers, targeting ligands for drug delivery, and NASMs. We also discuss the current challenges and future developmental directions.

Preparation and evaluation of lecithin/zein hybrid nanoparticles for the oral delivery of Panax notoginseng saponins

Panax Notoginseng Saponins (PNS) has been widely used in the prevention and treatment of cardiovascular and cerebrovascular diseases such as myocardial infarction, heart failure and cerebral infarction. However, oral administration of PNS showed low bioavailability because of its instability and poor membrane permeability in the gastrointestinal tract. Here, lipoprotein-inspired hybrid nanoparticles of PNS-Lecithin-Zein (PLZ-NPs) were prepared by using a simple phase separation method, which possessed a core-shell structure, where zein was used as protein part to replace the animal origin protein to increase the resistance to acid and enzymes while lecithin was used as the lipid composition to improve the oral absorption of PNS as well as to increase the drug loading capacity of PNS into the nanocarriers. The results of stability test showed that PLZ-NPs had robust enzymolysis resistance ability for acid and digestive enzymes of gastrointestinal environments. The fluorescent resonance energy transfer (FRET) assay confirmed the ability of LZ-NPs to be intactly absorbed by Caco-2 cell monolayer. Cell transport studies demonstrated that the permeability of PLZ-NPs in Caco-2/HT29-MTX co-culture cell model was 1.5-fold that of PNS. Meanwhile, the single-pass intestinal perfusion assay proved the absorption parameter Peff of PLZ-NPs was 1.75 and 1.80 times higher than that of PNS in the ileum and jejunum, respectively. Finally, the in vivo pharmacokinetic experiment showed that the relative oral bioavailability of PLZ-NPs was 1.71-fold that of free PNS in SD rat. In summary, the employment of the Lecithin/Zein hybrid nanoparticles could be considered as a promising approach for PNS analogues.

Preservation of the Antioxidant Capacity of Resveratrol via Encapsulation in Niosomes

Resveratrol (RSV) is a natural polyphenol which produces several benefits to human health, being the trans-isomer the most bioactive. However, its systemic absorption is limited due to its low water solubility, that reduces the oral bioavailability, and its chemical instability (owing to the trans-cis RSV isomer conversion upon light irradiation). Thus, encapsulation of this bioactive compound is required to protect it from destructive environmental conditions. Here, trans-RSV was encapsulated in food grade nanovesicles formed by Tween 80 and Span 80, with or without the addition of dodecanol (Dod) as membrane stabilizer. The size and shape of niosomes were evaluated by microscopy (TEM) and light scattering. RSV was successfully encapsulated in the vesicular systems (49-57%). The effect of Dod in the membrane bilayer was evaluated on the RSV in vitro release experiments under simulated gastrointestinal conditions. The total antioxidant capacity of the encapsulated polyphenol was measured using radicals' assays (DPPH and ABTS). The niosomes were able to maintain almost the total antioxidant capacity of encapsulated RSV, also preserved the ~85% of trans-RSV, thus offering considerable protection against high energy irradiation. These results make these systems suitable for different applications, particularly for photosensitive compounds.

Phenolic Compounds Impact on Rheumatoid Arthritis, Inflammatory Bowel Disease and Microbiota Modulation

Non-communicable chronic diseases (NCDs) are nowadays the principal cause of death, especially in most industrialized nations. These illnesses have increased exponentially with the consumption of diets very high in fat and sugar, not to mention stress and physical inactivity among other factors. The potential impact of suboptimal diets on NCDs’ morbidity and mortality rates brings to the forefront the necessity for a new way of improving dietary habits. The literature provides extensive scientific work that presents evidence that phenolic compounds from diets have antioxidant, anti-inflammatory and antiproliferative activities that impact human health. Gut microbiota modulation by some phenolic compounds leads to favorable changes in abundance, diversity, and in the immune system. However, polyphenol’s limited bioavailability needs to be overcome, highlighting their application in new delivery systems and providing their health benefits in well-established ways such as health maintenance, treatment or adjuvant to conventional pharmacological treatments. In this context, novel dietary approaches, including new food supplements, have emerged to prevent diseases and preserve health.

Inflammatory Bowel Disease: The Emergence of New Trends in Lifestyle and Nanomedicine as the Modern Tool for Pharmacotherapy

The human intestine, which harbors trillions of symbiotic microorganisms, may enter into dysbiosis when exposed to a genetic defect or environmental stress. The naissance of chronic inflammation due to the battle of the immune system with the trespassing gut bacteria leads to the rise of inflammatory bowel disease (IBD). Though the genes behind the scenes and their link to the disease are still unclear, the onset of IBD occurs in young adults and has expanded from the Western world into the newly industrialized countries. Conventional drug deliveries depend on a daily heavy dosage of immune suppressants or anti-inflammatory drugs targeted for the treatment of two types of IBD, ulcerative colitis (UC) and Crohn's disease (CD), which are often associated with systemic side effects and adverse toxicities. Advances in oral delivery through nanotechnology seek remedies to overcome the drawbacks of these conventional drug delivery systems through improved drug encapsulation and targeted delivery. In this review, we discuss the association of genetic factors, the immune system, the gut microbiome, and environmental factors like diet in the pathogenesis of IBD. We also review the various physiological concerns required for oral delivery to the gastrointestinal tract (GIT) and new strategies in nanotechnology-derived, colon-targeting drug delivery systems.