Functional lipid polymeric nanoparticles for oral drug delivery: Rapid mucus penetration and improved cell entry and cellular transport

Nano-based drug delivery systems for active ingredients from traditional Chinese medicine: Harnessing the power of nanotechnology

Introduction: Traditional Chinese medicine (TCM) is gaining worldwide popularity as a complementary and alternative medicine. The isolation and characterization of active ingredients from TCM has become optional strategies for drug development. In order to overcome the inherent limitations of these natural products such as poor water solubility and low bioavailability, the combination of nanotechnology with TCM has been explored. Taking advantage of the benefits offered by the nanoscale, various drug delivery systems have been designed to enhance the efficacy of TCM in the treatment and prevention of diseases. Methods: The manuscript aims to present years of research dedicated to the application of nanotechnology in the field of TCM. Results: The manuscript discusses the formulation, characteristics and therapeutic effects of nano-TCM. Additionally, the formation of carrier-free nanomedicines through self-assembly between active ingredients of TCM is summarized. Finally, the paper discusses the safety behind the application of nano-TCM and proposes potential research directions. Discussion: Despite some achievements, the safety of nano-TCM still need special attention. Furthermore, exploring the substance basis of TCM formulas from the perspective of nanotechnology may provide direction for elucidating the scientific intension of TCM formulas.

Impact of physicochemical properties on biological effects of lipid nanoparticles: Are they completely safe

Lipid nanoparticles (LNPs) are promising materials and human-use approved excipients, with manifold applications in biomedicine. Researchers have tended to focus on improving the pharmacological efficiency and organ targeting of LNPs, while paid relatively less attention to the negative aspects created by their specific physicochemical properties. Here, we discuss the impacts of LNPs' physicochemical properties (size, surface hydrophobicity, surface charge, surface modification and lipid composition) on the adsorption-transportation-distribution-clearance processes and bio-nano interactions. In addition, since there is a lack of review emphasizing on toxicological profiles of LNPs, this review outlined immunogenicity, inflammation, hemolytic toxicity, cytotoxicity and genotoxicity induced by LNPs and the underlying mechanisms, with the aim to understand the properties that underlie the biological effects of these materials. This provides a basic strategy that increased efficacy of medical application with minimized side-effects can be achieved by modulating the physicochemical properties of LNPs. Therefore, addressing the effects of physicochemical properties on toxicity induced by LNPs is critical for understanding their environmental and health risks and will help clear the way for LNPs-based drugs to eventually fulfill their promise as a highly effective therapeutic agents for diverse diseases in clinic.

Physiological Barriers and Strategies of Lipid-Based Nanoparticles for Nucleic Acid Drug Delivery

Lipid-based nanoparticles (LBNPs) are currently the most promising vehicles for nucleic acid drug (NAD) delivery. Although their clinical applications have achieved success, the NAD delivery efficiency and safety are still unsatisfactory, which are, to a large extent, due to the existence of multi-level physiological barriers in vivo. It is important to elucidate the interactions between these barriers and LBNPs, which will guide more rational design of efficient NAD vehicles with low adverse effects and facilitate broader applications of nucleic acid therapeutics. This review describes the obstacles and challenges of biological barriers to NAD delivery at systemic, organ, sub-organ, cellular, and subcellular levels. The strategies to overcome these barriers are comprehensively reviewed, mainly including physically/chemically engineering LBNPs and directly modifying physiological barriers by auxiliary treatments. Then the potentials and challenges for successful translation of these preclinical studies into the clinic are discussed. In the end, a forward look at the strategies on manipulating protein corona (PC) is addressed, which may pull off the trick of overcoming those physiological barriers and significantly improve the efficacy and safety of LBNP-based NADs delivery.

Lipid-Polymer Hybrid Nanosystems: A Rational Fusion for Advanced Therapeutic Delivery

Lipid nanoparticles (LNPs) are spherical vesicles composed of ionizable lipids that are neutral at physiological pH. Despite their benefits, unmodified LNP drug delivery systems have substantial drawbacks, including a lack of targeted selectivity, a short blood circulation period, and in vivo instability. lipid-polymer hybrid nanoparticles (LPHNPs) are the next generation of nanoparticles, having the combined benefits of polymeric nanoparticles and liposomes. LPHNPs are being prepared from both natural and synthetic polymers with various techniques, including one- or two-step methods, emulsification solvent evaporation (ESE) method, and the nanoprecipitation method. Varieties of LPHNPs, including monolithic hybrid nanoparticles, core-shell nanoparticles, hollow core-shell nanoparticles, biomimetic lipid-polymer hybrid nanoparticles, and polymer-caged liposomes, have been investigated for various drug delivery applications. However, core-shell nanoparticles having a polymeric core surrounded by a highly biocompatible lipid shell are the most commonly explored LPHNPs for the treatment of various diseases. In this review, we will shed light on the composition, methods of preparation, classification, surface functionalization, release mechanism, advantages and disadvantages, patents, and clinical trials of LPHNPs, with an emphasis on core-shell-structured LPHNPs.

Oral membrane-biomimetic nanoparticles for enhanced endocytosis and regulation of tumor-associated macrophage

Enterocyte uptake with high binding efficiency and minor endogenous interference remains a challenge in oral nanocarrier delivery. Enterocyte membrane-biomimetic lipids may universally cooperate with endogenous phosphatidyl choline via a biorthogonal group. In this study, we developed a sophorolipid-associated membrane-biomimetic choline phosphate-poly(lactic-co-glycolic) acid hybrid nanoparticle (SDPN). Aided by physical stability in the gastrointestinal tract and rapid mucus diffusion provided by association with sophorolipid, these nanoparticles show improved endocytosis, driven by dipalmitoyl choline phosphate-phosphatidyl choline interaction as well as its optimized membrane fluidity and rigidity. Luteolin- and silibinin-co-loaded with SDPN alleviated breast cancer metastasis in 4T1 tumor-bearing mice by regulating the conversion of tumor-associated M2 macrophages into the M1 phenotype and reducing the proportion of the M2-phenotype through co-action on STAT3 and HIF-1α. In addition, SDPN reduces angiogenesis and regulates the matrix barrier in the tumor microenvironment. In conclusion, this membrane-biomimetic strategy is promising for improving the enterocyte uptake of oral SDPN and shows potential to alleviate breast cancer metastasis.

Solid Lipid Nanoparticles vs. Nanostructured Lipid Carriers: A Comparative Review

Solid-lipid nanoparticles and nanostructured lipid carriers are delivery systems for the delivery of drugs and other bioactives used in diagnosis, therapy, and treatment procedures. These nanocarriers may enhance the solubility and permeability of drugs, increase their bioavailability, and extend the residence time in the body, combining low toxicity with a targeted delivery. Nanostructured lipid carriers are the second generation of lipid nanoparticles differing from solid lipid nanoparticles in their composition matrix. The use of a liquid lipid together with a solid lipid in nanostructured lipid carrier allows it to load a higher amount of drug, enhance drug release properties, and increase its stability. Therefore, a direct comparison between solid lipid nanoparticles and nanostructured lipid carriers is needed. This review aims to describe solid lipid nanoparticles and nanostructured lipid carriers as drug delivery systems, comparing both, while systematically elucidating their production methodologies, physicochemical characterization, and in vitro and in vivo performance. In addition, the toxicity concerns of these systems are focused on.

Diethylene glycol monoethyl ether-mediated nanostructured lipid carriers enhance trans-ferulic acid delivery by Caco-2 cells superior to solid lipid nanoparticles

This work aimed to compare the performance of trans-ferulic acid-encapsulated nanostructured lipid carriers (NLCs) and solid lipid nanoparticles (SLNs) for transport by Caco-2 cells. The NLC particles (diameter: 102.6 nm) composed of Compritol^® 888 ATO, ethyl oleate, Cremophor^® EL, and Transcutol^® P were larger than the SLNs (diameter: 86.0 nm) formed without liquid lipid (ethyl oleate), and the former had a higher encapsulation efficiency for trans-ferulic acid (p < 0.05). In vitro cultured Caco-2 cell transport was used to simulate intestinal absorption, and the cellular uptake of NLCs was higher than that of SLNs (p < 0.05). Compared to SLNs, NLCs greatly enhanced trans-ferulic acid permeation through the Millicell^TM membrane (p < 0.05). This work confirms that NLCs have better properties than SLNs in terms of increasing drug transport by Caco-2 cells. This helps to comprehend the approach by which NLC-mediated oral bioavailability of trans-ferulic acid is better than that mediated by SLNs, as shown in our previous report.

Ligand-modified nanocarriers for oral drug delivery: Challenges, rational design, and applications

Ligand-modified nanocarriers (LMNCs) specific to their targets have attracted increasing interest for enhanced oral drug delivery in recent decades. Although the design of LMNCs for enhanced endocytosis and improved exposure of the loaded drugs through the oral route has received abundant attention, it remains unclear how the design influences their transcellular process, especially the key factors affecting their functions. This review discusses the extracellular and cellular barriers to orally administered LMNCs in the gastrointestinal (GI) tract and new discoveries regarding the GI protein corona and the sequential transport barriers that impede the preplanned movements of LMNCs after oral administration. Furthermore, innovative progress in considering key factors (including target selection, ligand properties, and other important factors) in the rational design of LMNCs for oral drug delivery is presented. In particular, some factors that endow LMNCs with efficient transcytosis rather than only endocytosis are highlighted. Finally, the prospects of orally administered LMNCs in disease therapy for the enhanced oral/local bioavailability of active pharmaceutical ingredients, as well as emerging delivery routes, such as lymphatic drug delivery and systemic location-specific drug release based on oral transcellular LMNCs, are discussed.

Review of Novel Oral Amphotericin B Formulations for the Treatment of Parasitic Infections

Amphotericin B (AmpB) is a polyene macrolide antibiotic used in the treatment of blood-borne parasitic and fungal infections. However, its use, particularly in the developing world, has been limited by dose-dependent kidney toxicity, other systemic-related toxicity issues following injection, the inconvenience of parenteral administration, and accessibility. Oral formulation approaches have focused on the dual problem of solubility and permeability of AmpB, which is poorly water soluble, amphoteric and has extremely low oral bioavailability. Therefore, to enhance oral absorption, researchers have employed micellar formulations, polymeric nanoparticles, cochleates, pro-drugs, and self-emulsifying drug delivery systems (SEDDS). This paper will highlight current uses of AmpB against parasitic infections such as leishmaniasis, preclinical and clinical formulation strategies, applications in veterinary medicine and the importance of developing a cost-effective and safe oral AmpB formulation.

From Static to Dynamic: A Review on the Role of Mucus Heterogeneity in Particle and Microbial Transport

Mucus layers (McLs) are on the front line of the human defense system that protect us from foreign abiotic/biotic particles (e.g., airborne virus SARS-CoV-2) and lubricates our organs. Recently, the impact of McLs on human health (e.g., nutrient absorption and drug delivery) and diseases (e.g., infections and cancers) has been studied extensively, yet their mechanisms are still not fully understood due to their high variety among organs and individuals. We characterize these variances as the heterogeneity of McLs, which lies in the thickness, composition, and physiology, making the systematic research on the roles of McLs in human health and diseases very challenging. To advance mucosal organoids and develop effective drug delivery systems, a comprehensive understanding of McLs' heterogeneity and how it impacts mucus physiology is urgently needed. When the role of airway mucus in the penetration and transmission of coronavirus (CoV) is considered, this understanding may also enable a better explanation and prediction of the CoV's behavior. Hence, in this Review, we summarize the variances of McLs among organs, health conditions, and experimental settings as well as recent advances in experimental measurements, data analysis, and model development for simulations.

The Promise of Nanotechnology in Personalized Medicine

Both personalized medicine and nanomedicine are new to medical practice. Nanomedicine is an application of the advances of nanotechnology in medicine and is being integrated into diagnostic and therapeutic tools to manage an array of medical conditions. On the other hand, personalized medicine, which is also referred to as precision medicine, is a novel concept that aims to individualize/customize therapeutic management based on the personal attributes of the patient to overcome blanket treatment that is only efficient in a subset of patients, leaving others with either ineffective treatment or treatment that results in significant toxicity. Novel nanomedicines have been employed in the treatment of several diseases, which can be adapted to each patient-specific case according to their genetic profiles. In this review, we discuss both areas and the intersection between the two emerging scientific domains. The review focuses on the current situation in personalized medicine, the advantages that can be offered by nanomedicine to personalized medicine, and the application of nanoconstructs in the diagnosis of genetic variability that can identify the right drug for the right patient. Finally, we touch upon the challenges in both fields towards the translation of nano-personalized medicine.

Untangling Mucosal Drug Delivery: Engineering, Designing, and Testing Nanoparticles to Overcome the Mucus Barrier

Mucus is a complex viscoelastic gel and acts as a barrier covering much of the soft tissue in the human body. High vascularization and accessibility have motivated drug delivery to various mucosal surfaces; however, these benefits are hindered by the mucus layer. To overcome the mucus barrier, many nanomedicines have been developed, with the goal of improving the efficacy and bioavailability of drug payloads. Two major nanoparticle-based strategies have emerged to facilitate mucosal drug delivery, namely, mucoadhesion and mucopenetration. Generally, mucoadhesive nanoparticles promote interactions with mucus for immobilization and sustained drug release, whereas mucopenetrating nanoparticles diffuse through the mucus and enhance drug uptake. The choice of strategy depends on many factors pertaining to the structural and compositional characteristics of the target mucus and mucosa. While there have been promising results in preclinical studies, mucus-nanoparticle interactions remain poorly understood, thus limiting effective clinical translation. This article reviews nanomedicines designed with mucoadhesive or mucopenetrating properties for mucosal delivery, explores the influence of site-dependent physiological variation among mucosal surfaces on efficacy, transport, and bioavailability, and discusses the techniques and models used to investigate mucus-nanoparticle interactions. The effects of non-homeostatic perturbations on protein corona formation, mucus composition, and nanoparticle performance are discussed in the context of mucosal delivery. The complexity of the mucosal barrier necessitates consideration of the interplay between nanoparticle design, tissue-specific differences in mucus structure and composition, and homeostatic or disease-related changes to the mucus barrier to develop effective nanomedicines for mucosal delivery.

Bromelain Loaded Lipid-Polymer Hybrid Nanoparticles for Oral Delivery: Formulation and Characterization

Bromelain (Br), a mixture of proteolytic enzymes from pineapple (Ananas comosus), has various therapeutic potentials; however, its low bioavailability has limited the clinical applications specifically in oral delivery as the most common convenient used route of administration. In the present study, a lipopolymeric nanoparticle (NP) containing Br was developed to enhance its stability and oral delivery efficiency. Firstly, Br was loaded into poly (D, L-lactide-co-glycolide acid) (PLGA) and PLGA-phosphatidylcholine (PLGA-PC) NPs using double emulsion solvent evaporation technique. Then, Br integrity and activity were investigated using SDS-PAGE and gelatin test. The stability and release profile of Br from synthetized NPs were evaluated at different pH values of the digestive system. Furthermore, cytotoxicity, cellular uptake, and the amount of Br passage from Caco-2 cells were explored. The results showed PLGA-PC-Br NPs had higher encapsulation efficiency (83%) compared to PLGA-Br NPs (50%). In addition, this NP showed more Br released in neutral (20.36%) and acidic (34%) environments compared to PLGA-Br NPs after 5 days. The delay in the release of Br from PLGA-PC-Br NPs versus the faster release of Br from PLGA-Br formulation could assure that an appropriate concentration of Br has reached the intestine. Intestinal absorption study demonstrated that lipid polymer NPs were able to pass through Caco-2 cells about 1.5 times more (98.4%) than polymeric NPs (70%). In conclusion, PLGA-PC NPs would be considered as a promising lipid-polymer nanocarrier for effective intestinal absorption of Br.

Impact of nanomaterials on the intestinal mucosal barrier and its application in treating intestinal diseases

The intestinal mucosal barrier (IMB) is one of the important barriers to prevent harmful substances and pathogens from entering the body environment and to maintain intestinal homeostasis. The dysfunction of the IMB is associated with intestinal diseases and disorders. Nanomaterials have been widely used in medicine and as drug carriers due to their large specific surface area, strong adsorbability, and good biocompatibility. In this review, we comprehensively discuss the impact of typical nanomaterials on the IMB and summarize the treatment of intestinal diseases by using nanomaterials. The effects of nanomaterials on the IMB are mainly influenced by factors such as the dosage, size, morphology, and surface functional groups of nanomaterials. There is huge potential and a broad prospect for the application of nanomaterials in regulating the IMB for achieving an optimal therapeutic effect for antibiotics, oral vaccines, drug carriers, and so on.

Mimicking the Gastrointestinal Mucus Barrier: Laboratory-Based Approaches to Facilitate an Enhanced Understanding of Mucus Permeation

The gastrointestinal mucus layer plays a significant role in maintaining gut homeostasis and health, offering protective capacities against the absorption of harmful pathogens as well as commensal gut bacteria and buffering stomach acid to protect the underlying epithelium. Despite this, the mucus barrier is often overlooked during preclinical pharmaceutical development and may pose a significant absorption barrier to high molecular weight or lipophilic drug species. The complex chemical and physical nature of the dynamic mucus layer has proven problematic to reliably replicate in a laboratory setting, leading to the development of multiple mucus models with varying complexity and predictive capacity. This, coupled with the wide range of analysis methods available, has led to a plethora of possible approaches to quantifying mucus permeation; however, the field remains significantly under-represented in biomedical research. For this reason, the development of a concise collation of the available approaches to mucus permeation is essential. In this review, we explore widely utilized mucus mimics ranging in complexity from simple mucin solutions to native mucus preparations for their predictive capacity in mucus permeation analysis. Furthermore, we highlight the diverse range of laboratory-based models available for the analysis of mucus interaction and permeability with a specific focus on in vitro, ex vivo, and in situ models. Finally, we highlight the predictive capacity of these models in correlation with in vivo pharmacokinetic data. This review provides a comprehensive and critical overview of the available technologies to analyze mucus permeation, facilitating the efficient selection of appropriate tools for further advancement in oral drug delivery.

Nanoparticulate Drug Delivery Strategies to Address Intestinal Cytochrome P450 CYP3A4 Metabolism towards Personalized Medicine

Drug dosing in clinical practice, which determines optimal efficacy, toxicity or ineffectiveness, is critical to patients' outcomes. However, many orally administered therapeutic drugs are susceptible to biotransformation by a group of important oxidative enzymes, known as cytochrome P450s (CYPs). In particular, CYP3A4 is a low specificity isoenzyme of the CYPs family, which contributes to the metabolism of approximately 50% of all marketed drugs. Induction or inhibition of CYP3A4 activity results in the varied oral bioavailability and unwanted drug-drug, drug-food, and drug-herb interactions. This review explores the need for addressing intestinal CYP3A4 metabolism and investigates the opportunities to incorporate lipid-based oral drug delivery to enable precise dosing. A variety of lipid- and lipid-polymer hybrid-nanoparticles are highlighted to improve drug bioavailability. These drug carriers are designed to target different intestinal regions, including (1) local saturation or inhibition of CYP3A4 activity at duodenum and proximal jejunum; (2) CYP3A4 bypass via lymphatic absorption; (3) pH-responsive drug release or vitamin-B12 targeted cellular uptake in the distal intestine. Exploitation of lipidic nanosystems not only revives drugs removed from clinical practice due to serious drug-drug interactions, but also provide alternative approaches to reduce pharmacokinetic variability.

A systematic review of functionalized polymeric nanoparticles to improve intestinal permeability of drugs and biological products

BACKGROUND

The oral route is the most frequently used and the most convenient route of drug administration, since it has several advantages, such as ease of use, patient compliance and better cost-effectiveness. However, physicochemical and biopharmaceutical limitations of various active pharmaceutical ingredients (API) hinder suitability for this route, including degradation in the gastrointestinal tract, low intestinal permeability and low bioavailability. To overcome these problems, while maintaining therapeutic efficacy, polymeric nanoparticles have attracted considerable attention for their ability to increase drug solubility, promote controlled release, and improve stability. In addition, the functionalization of nanocarriers can increase uptake and accumulation at the target site of action, and intestinal absorption, making it possible to obtain more viable, safe and efficient treatments for oral administration. <P> Objective: This systematic review aimed to seek recent advances in the literature on the use of polymeric nanoparticles functionalization to increase intestinal permeability of APIs that are intended for oral administration. <P> Method: Two bibliographic databases were consulted (PubMed and ScienceDirect). The selected publications and the writing of this systematic review were based on the guidelines mentioned in the PRISMA statement. <P> Results: Out of a total of 3036 studies, 22 studies were included in this article based on our eligibility criteria. The results were consistent for the application of nanoparticle functionalization to increase intestinal permeability. <P> Conclusion: The functionalized polymeric nanoparticles can be considered as carrier systems that improve the intestinal permeability and bioavailability of APIs, with the potential to result, in the future, in the development of oral medicines.

Nanocrystals for Improving Oral Bioavailability of Drugs: Intestinal Transport Mechanisms and Influencing Factors

With the limitation of solubility and dissolution rate of insoluble drugs, following oral administration, they would rifely prove poor and volatile bioavailability, which may fail to realize its therapeutic value. The drug nanocrystals are perceived as effective tactic for oral administration of insoluble drugs attributes to possess many prominent properties such as elevating dissolution rate and saturation solubility, high drug loading capacity, and improving oral bioavailability. Based on these advantages, the application of nanocrystals in oral drug delivery has acquired significant achievement, and so far more than 20 products of drug nanocrystals have been confirmed in the market. However, the oral absorption of drug nanocrystals is still facing huge challenges due to the limitation of many factors. Intrinsic properties of the drugs and complex physiological environment of the intestinal tract are the two most important factors affecting the oral bioavailability of drugs. In addition, the research on the multi-aspect mechanisms of nanocrystals promoting gastrointestinal absorption and bioavailability has been gradually deepened. In this review, we summarized recent advances of the nanocrystals delivered orally, and provided an overview to the research progress for crossing the intestinal tract transport mechanisms of the nanocrystals by some new research techniques. Meanwhile, the factors relevant to the transport of drug nanocrystals were also elaborated in detail. Graphical Abstract.

Polymeric Lipid Hybrid Nanoparticles as a Delivery System Enhance the Antitumor Effect of Emodin in Vitro and in Vivo

This study aimed to evaluate the therapeutic efficacy of Emodin-loaded polymer lipid hybrid nanoparticles (E-PLNs) for breast cancer. The size, Zeta potential, surface morphology, encapsulation efficiency, stability, in vitro drug release of E-PLNs prepared by the nanoprecipitation method were characterized. The uptake, in-vitro cytotoxicities and apoptosis of free drug, E-PLNs were investigated against MCF-7 cells. The efficacy of E-PLNs in tumor bearing nude mice has also been studied.The average particle size of the experimentally prepared E-PLNs was (122.7±1.79) nm, and the encapsulation rate was 72.8%. Compared with free Emodin (EMO), E-PLNs showed greater toxicity to MCF-7 cells by promoting the uptake of EMO, and can promote the early apoptosis of MCF-7 cells. In addition to the morphological changes of apoptotic cells, the ratio of Bax/Bcl-2 was significantly increased, which indicated that E-PLNs can induce apoptosis in MCF-7 cells to achieve anticancer effect. Finally, E-PLNs significantly inhibited tumor growth by more than 60%, which may be related to its passive targeting effect on tumor site. Our results suggest that E-PLNs have shown good anti-breast cancer effect than free EMO. Moreover, the effect of E-PLNs on MCF-7 cells is mainly related to the induction of apoptosis.

Current Nanocarrier Strategies Improve Vitamin B12 Pharmacokinetics, Ameliorate Patients' Lives, and Reduce Costs

Vitamin B12 (VitB12) is a naturally occurring compound produced by microorganisms and an essential nutrient for humans. Several papers highlight the role of VitB12 deficiency in bone and heart health, depression, memory performance, fertility, embryo development, and cancer, while VitB12 treatment is crucial for survival in inborn errors of VitB12 metabolism. VitB12 is administrated through intramuscular injection, thus impacting the patients’ lifestyle, although it is known that oral administration may meet the specific requirement even in the case of malabsorption. Furthermore, the high-dose injection of VitB12 does not ensure a constant dosage, while the oral route allows only 1.2% of the vitamin to be absorbed in human beings. Nanocarriers are promising nanotechnology that can enable therapies to be improved, reducing side effects. Today, nanocarrier strategies applied at VitB12 delivery are at the initial phase and aim to simplify administration, reduce costs, improve pharmacokinetics, and ameliorate the quality of patients’ lives. The safety of nanotechnologies is still under investigation and few treatments involving nanocarriers have been approved, so far. Here, we highlight the role of VitB12 in human metabolism and diseases, and the issues linked to its molecule properties, and discuss how nanocarriers can improve the therapy and supplementation of the vitamin and reduce possible side effects and limits.

Advanced delivery strategies facilitating oral absorption of heparins

Heparins show great anticoagulant effect with few side effects, and are administered by subcutaneous or intravenous route in clinics. To improve patient compliance, oral administration is an alternative route. Nonetheless, oral administration of heparins still faces enormous challenges due to the multiple obstacles. This review briefly analyzes a series of barriers ranging from poorly physicochemical properties of heparins, to harsh biological barriers including gastrointestinal degradation and pre-systemic metabolism. Moreover, several approaches have been developed to overcome these obstacles, such as improving stability of heparins in the gastrointestinal tract, enhancing the intestinal epithelia permeability and facilitating lymphatic delivery of heparins. Overall, this review aims to provide insights concerning advanced delivery strategies facilitating oral absorption of heparins.

Prospects on Nano-Based Platforms for Antimicrobial Photodynamic Therapy Against Oral Biofilms

Objective: This review clusters the growing field of nano-based platforms for antimicrobial photodynamic therapy (aPDT) targeting pathogenic oral biofilms and increase interactions between dental researchers and investigators in many related fields. Background data: Clinically relevant disinfection of dental tissues is difficult to achieve with aPDT alone. It has been found that limited penetrability into soft and hard dental tissues, diffusion of the photosensitizers, and the small light absorption coefficient are contributing factors. As a result, the effectiveness of aPDT is reduced in vivo applications. To overcome limitations, nanotechnology has been implied to enhance the penetration and delivery of photosensitizers to target microorganisms and increase the bactericidal effect. Materials and methods: The current literature was screened for the various platforms composed of photosensitizers functionalized with nanoparticles and their enhanced performance against oral pathogenic biofilms. Results: The evidence-based findings from the up-to-date literature were promising to control the onset and the progression of dental biofilm-triggered diseases such as dental caries, endodontic infections, and periodontal diseases. The antimicrobial effects of aPDT with nano-based platforms on oral bacterial disinfection will help to advance the design of combination strategies that increase the rate of complete and durable clinical response in oral infections. Conclusions: There is enthusiasm about the potential of nano-based platforms to treat currently out of the reach pathogenic oral biofilms. Much of the potential exists because these nano-based platforms use unique mechanisms of action that allow us to overcome the challenging of intra-oral and hard-tissue disinfection.

Functional oral nanoparticles for delivering silibinin and cryptotanshinone against breast cancer lung metastasis

Background

Breast cancer lung metastasis occurs in more than 60% of all patients with breast cancer, and most of those afflicted by it eventually die of recurrence. The tumor microenvironment plays vital roles in metastasis. Modulating the tumor microenvironment via multiple pathways could efficiently prevent or inhibit lung metastasis. Silibinin and cryptotanshinone are natural plant products that demonstrate anti-metastasis effects and modulate the tumor microenvironment via different pathways. However, they have poor aqueous solubility, membrane permeability, and oral bioavailability. Oral drug administration may help improve the quality of life and compliance of patients with breast cancer, primarily under long-term and/or follow-up therapy. Herein, we developed poly-N-(2-hydroxypropyl) methacrylamide (pHPMA)-coated wheat germ agglutinin-modified lipid-polymer hybrid nanoparticles, co-loaded with silibinin and cryptotanshinone (S/C-pW-LPNs). We assessed their oral bioavailability, and evaluated their anti-metastasis efficacy in a 4T1 breast cancer tumor-bearing nude mouse model.

Results

An in vitro mucus diffusion study revealed that pHPMA enhanced W-LPN mucus penetration. After oral administration, pHPMA enhanced nanoparticle distribution in rat jejunum and substantially augmented oral bioavailability. S/C-W-LPNs markedly increased 4T1 cell toxicity and inhibited cell invasion and migration. Compared to LPNs loaded with either silibinin or cryptotanshinone alone, S/C-pW-LPNs dramatically slowed tumor progression in 4T1 tumor-bearing nude mice. S/C-pW-LPNs presented with the most robust anti-metastasis activity on smooth lung surfaces and mitigated lung metastasis foci. They also downregulated tumor microenvironment biomarkers such as CD31, TGF-β1, and MMP-9 that promote metastasis.

Conclusions

Silibinin- and cryptotanshinone-co-loaded pW-LPNs efficiently penetrate intestinal barriers, thereby enhancing the oral bioavailability of the drug loads. These nanoparticles exhibit favorable anti-metastasis effects in breast cancer-bearing nude mice. Hence, S/C-pW-LPNs are promising oral drug nanocarriers that inhibit breast cancer lung metastasis.