Angiopep-2 modified PE-PEG based polymeric micelles for amphotericin B delivery targeted to the brain

Polymeric Nanosystems: A Breakthrough Approach to Treating Inflammation and Inflammation Related Diseases

Inflammation processes can cause mild to severe damage in the human body and can lead to a large number of inflammation-related diseases (IRD) such as cancer, neural, vascular, and pulmonary diseases. Limitations of anti-inflammatory drugs (AID) application are reflected in high therapeutic doses, toxicity, low bioavailability and solubility, side effects, etc. Polymeric nanosystems (PS) have been recognized as a safe and effective technology that is able to overcome these limitations by AID encapsulation and is able to answer to the specific demands of the IRD treatment. PS are attracting great attention due to their versatility, biocompatibility, low toxicity, fine-tuned properties, functionality, and ability for precise delivery of anti-inflammatory drugs to the targeted sites in the human body. This article offers an overview of three classes of polymeric nanosystems: a) dendrimers, b) polymeric micelles and polymeric nanoparticles, and c) polymeric filomicelles, as well as their properties, preparation, and application in IRD treatment. In the future, the number of PS formulations in clinical practice will certainly increase.

iPSC-derived exosomes as amphotericin B carriers: a promising approach to combat cryptococcal meningitis

Background

Cryptococcal meningitis (CM) is a significant global health issue, particularly affecting individuals with HIV. Amphotericin B (AmB) serves as the cornerstone treatment for CM; however, its clinical application is restricted due to limited penetration of the blood-brain barrier and associated nephrotoxicity.

Objective

This study investigates the use of exosomes derived from induced pluripotent stem cells (iPSC-Exos) as carriers for AmB in treating CM, aiming to enhance therapeutic efficacy and safety and reduce AmB toxicity.

Methods

Exosomes were extracted from iPSC culture supernatants using ultrafiltration and ultracentrifugation. Their morphology and size were analyzed using transmission electron microscopy (TEM) and nanoparticle flow cytometry (nFCM). Purity was confirmed by Western blotting for markers CD9, CD63, and TSG101. AmB was loaded into iPSC-Exos using a co-incubation method. The cytotoxicity of the iPSC-Exo/AmB complex was evaluated on HEK 293 T and RAW264.7 cells using the CCK-8 assay, while apoptosis was assessed using live/dead cell staining and flow cytometry. The hemolytic effects were tested using rabbit red blood cells. In a C57BL/6 J mouse model of cryptococcal infection, treatment groups (AmB, iPSC-Exo/AmB, and iPSC-Exo) were administered corresponding drugs, with blood and brain samples collected for analysis. The minimum inhibitory concentration (MIC) of iPSC-Exo/AmB and conventional AmB against Cryptococcus was determined.

Results

The iPSC-Exo/AmB complex exhibited reduced cytotoxicity in vitro and decreased AmB-induced renal and hepatic toxicity in vivo. Its MIC against Cryptococcus was over eight times lower than conventional AmB, significantly reducing fungal burden in the mouse brain and lowering serum inflammatory factors.

Conclusion

The iPSC-Exo/AmB complex is a promising therapeutic strategy that enhances AmB efficacy while reducing toxicity, offering new hope for treating CM and other refractory fungal infections of the central nervous system.

Nano-Polymers as Cas9 Inhibitors

Despite wide applications of CRISPR/Cas9 technology, effective approaches for CRISPR delivery with functional control are limited. In an attempt to develop a nanoscale CRSIPR/Cas9 delivery platform, we discovered that several biocompatible polymers, including polymalic acid (PMLA), polyglutamic acid (PGA), and polyaspartic acid (PLD), when conjugated with a trileucine (LLL) moiety, can effectively inhibit Cas9 nuclease function. The Cas9 inhibition by those polymers is dose-dependent, with varying efficiency to achieve 100% inhibition. Further biophysical studies revealed that PMLA-LLL directly binds the Cas9 protein, resulting in a substantial decrease in Cas9/sgRNA binding affinity. Transmission electron microscopy and molecular docking were performed to provide a possible binding mechanism for PMLA-LLL to interact with Cas9. This work identified a new class of Cas9 inhibitor in nano-polymer form. These biodegradable polymers may serve as novel Cas9 delivery vehicles with a potential to enhance the precision of Cas9-mediated gene editing.

Hydrogen sulfide-generating semiconducting polymer nanoparticles for amplified radiodynamic-ferroptosis therapy of orthotopic glioblastoma

A variety of therapeutic strategies are available to treat glioblastoma (GBM), but the tumor remains one of the deadliest due to its aggressive invasiveness, restrictive blood-brain barrier (BBB), and exceptional resistance to drugs. In this study, we present a hydrogen sulfide (H2S)-generating semiconducting polymer nanoparticle (PFeD@Ang) for amplified radiodynamic-ferroptosis therapy of orthotopic glioblastoma. Our results show that in an acidic tumor microenvironment (TME), H2S donors produce large amounts of H2S, which inhibits mitochondrial respiration and alleviates cellular hypoxia, thus enhancing the radiodynamic effect during X-ray irradiation; meanwhile, Fe3+ is reduced to Fe2+ by tannic acid in an acidic TME, which promotes an iron-dependent cell death process in tumors. H2S facilitates the ferroptosis process by increasing the local H2O2 concentration via inhibiting catalase activity. This kind of amplified radiodynamic-ferroptosis therapeutic strategy could remarkably inhibit glioma progression in an orthotopic GBM mouse model. Our study demonstrates the potential of PFeD@Ang for GBM treatment via targeted delivery and combinational therapeutic actions of RDT and ferroptosis therapy.

Targeting Brain Drug Delivery with Macromolecules Through Receptor-Mediated Transcytosis

Brain diseases pose significant treatment challenges due to the restrictive nature of the blood-brain barrier (BBB). Recent advances in targeting macromolecules offer promising avenues for overcoming these obstacles through receptor-mediated transcytosis (RMT). We summarize the current progress in targeting brain drug delivery with macromolecules for brain diseases. This exploration details the transport mechanisms across the BBB, focusing on RMT and its use of natural ligands for drug delivery. Furthermore, the review examines macromolecular ligands such as antibodies, peptides, and aptamers that leverage RMT for effective BBB traversal. Advancements in macromolecules-based delivery systems for brain diseases are summarized, emphasizing their therapeutic potential and limitations. Finally, emerging RMT strategies, including viral vectors, exosomes, and boron neutron capture therapy, are discussed for their precision in brain-targeted treatments. This comprehensive overview underscores the potential of RMT-based approaches to revolutionize brain disease therapy.

Nanoparticles in CNS Therapeutics: Pioneering Drug Delivery Advancements

INTRODUCTION

The incidence of Central Nervous System (CNS) disorders, including Parkinson's disease, Alzheimer's disease, stroke, and malignancies, has risen significantly in recent decades, contributing to millions of deaths annually. Efficacious treatment of these disorders requires medicines targeting the brain. The Blood-brain Barrier (BBB) poses a formidable challenge to effective drug delivery to the brain, hindering progress in CNS therapeutics. This review explores the latest developments in nanoparticulate carriers, highlighting their potential to overcome BBB limitations.

OBJECTIVE

This study aimed to evaluate and summarise the critical factors and pathways in the nanoparticle- based CNS targeted drug delivery.

METHODS

An extensive literature search was conducted, comprising the initial development of nanoparticle- based CNS-targeted drug delivery approaches to the latest advancements using various online search tools.

RESULTS

The properties of nanoparticles, such as type of nanoparticles, size, shape, surface charge, hydrophobicity, and surface functionalisation, along with properties of the BBB during normal and pathological conditions and their impact on the delivery of nanoparticles across the BBB, are identified and discussed here.

CONCLUSION

Important properties and pathways that determine the penetration of nanoparticles across the CNS are reviewed in this article, along with recent advances in the field.

Advancing cryptococcal treatment: The role of nanoparticles in mitigating antifungal resistance

Cryptococcus, a ubiquitous and formidable fungal pathogen, contributes to a substantial global disease burden, with nearly 250,000 cases and 181,000 fatalities attributed to cryptococcal meningitis annually worldwide. The invasive nature of Cryptococcus presents significant challenges in treatment and management, as it mostly affects vulnerable populations, including HIV patients, organ transplant recipients, pregnant women, and elderly individuals. Moreover, these difficulties are exacerbated by the development of antifungal resistance, which emphasizes the need for efficient control measures. In this context, research efforts focusing on infection control and novel therapeutic strategies become paramount. Nanoparticle-based therapies emerge as a solution, offering advanced antifungal properties and improved efficacy. Developing effective treatment options requires understanding the complex landscape of cryptococcal infections and the innovative potential of nanoparticle-based therapies. This review highlights the urgent need for novel strategies to combat the growing threat posed by antifungal resistance while offering insights into the intricate realm of cryptococcal infections, particularly focusing on the promising role of nanoparticle-based therapies.

Nanomaterial-based therapeutics for enhanced antifungal therapy

The application of nanotechnology in antifungal therapy is gaining increasing attention. Current antifungal drugs have significant limitations, such as severe side effects, low bioavailability, and the rapid development of resistance. Nanotechnology offers an innovative solution to address these issues. This review discusses three key strategies of nanotechnology to enhance antifungal efficacy. Firstly, nanomaterials can enhance their interaction with fungal cells via ingenious surface tailoring of nanomaterials. Effective adhesion of nanoparticles to fungal cells can be achieved by electrostatic interaction or specific targeting to the fungal cell wall and cell membrane. Secondly, stimuli-responsive nanomaterials are developed to realize smart release of drugs in the specific microenvironment of pathological tissues, such as the fungal biofilm microenvironment and inflammatory microenvironment. Thirdly, nanomaterials can be designed to cross different physiological barriers, effectively addressing challenges posed by skin, corneal, and blood-brain barriers. Additionally, some new nanomaterial-based strategies in treating fungal infections are discussed, including the development of fungal vaccines, modulation of macrophage activity, phage therapy, the application of high-throughput screening in drug discovery, and so on. Despite the challenges faced in applying nanotechnology to antifungal therapy, its significant potential and innovation open new possibilities for future clinical antifungal applications.

Coadministration of Quercetin and Indocyanine Green via PEGylated Phospholipid Micelles for Augmented Chem-Photothermal Combination Tumor Therapy

A significant impediment persists in developing multicomponent nanomedicines designed to dismantle the heat shock protein (HSP)-based protective mechanism of malignant tumors during photothermal therapy. Herein, well-defined PEGylated phospholipid micelles were utilized to coencapsulate quercetin (QUE, a natural anticancer agent and potent HSP inhibitor) and indocyanine green (ICG, a photothermal agent) with the aim of achieving synchronized and synergistic drug effects. The subsequent investigations validated that the tailored micellar system effectively enhanced QUE's water solubility and augmented its cellular internalization efficiency. Intriguingly, the compositional PEGylated phospholipids induced extraordinary endoplasmic reticulum stress, thereby sensitizing the tumor cells to QUE. Furthermore, QUE played a crucial role in inhibiting the stress-induced overexpression of HSP70, thereby augmenting the photothermal efficacy of ICG. In systemic applications, the proposed nanotherapeutics exhibited preferential accumulation within tumors and exerted notable tumoricidal effects against 4T1 xenograft tumors under 808 nm near-infrared irradiation, facilitated by prominent near-infrared fluorescence imaging-guided chemo-photothermal therapy. Therefore, our strategy for fabricating multicomponent nanomedicines emerges as a coordinated platform for optimizing antitumor therapeutic efficacy and offers valuable insights for diverse therapeutic modalities.

Long-Circulating and Brain-Targeted Liposomes Loaded with Isoliquiritigenin: Formation, Characterization, Pharmacokinetics, and Distribution

Isoliquiritigenin (ISL) has excellent neuroprotective effects. However, its limitations, including poor solubility, low bioavailability, and low accumulation in the brain, restrict its clinical promotion. In this study, a novel type of ISL-loaded liposome (ISL-LP) modified with the brain-targeting polypeptide angiopep-2 was prepared to improve these properties. The zeta potential, morphology, particle size, encapsulation efficiency, drug loading, and in vitro release of ISL-LP were evaluated. The pharmacokinetics and tissue distribution of ISL and ISL-LP were also investigated. The results demonstrated that ISL-LP had an average particle size of 89.36 ± 5.04 nm, a polymer dispersity index of 0.17 ± 0.03, a zeta potential of -20.27 ± 2.18 mV, and an encapsulation efficiency of 75.04 ± 3.28%. The in vitro release experiments indicate that ISL-LP is a desirable sustained-release system. After intravenous administration, LPC-LP prolonged the circulation time of ISL in vivo and enhanced its relative brain uptake. In conclusion, ISL-LP could serve as a promising brain-targeting system for the treatment and prevention of central nervous system (CNS) disorders.

The interaction of plant flavones with amphotericin B: Consequences for its pore-forming ability

The growth of antibiotic resistance to antifungal drugs contributes to the search for new ways to enhance their effectiveness and reduce toxicity. The undeniable advantage of polyene macrolide antibiotic amphotericin B (AmB) which ensures low pathogen resistance is its mechanism of action related to the formation of transmembrane pores in target lipid membranes. Here, we investigated the effects of plant flavones, chrysin, wogonin, baicalein, apigenin, scutellarein, luteolin, morin and fisetin on the pore-forming activity of AmB in the sterol-enriched membranes by electrophysiological assays. Сhrysin, wogonin, baicalein, apigenin, scutellarein, and luteolin were shown to decrease the AmB pore-forming activity in the bilayers composed of palmitoyloleylphosphocholine independently of their sterol composition. Morin and fisetin led to the increase and decrease in the AmB pore-forming activity in the ergosterol- and cholesterol-containing bilayers respectively. Differential scanning microcalorimetry of the gel-to-liquid crystalline phase transition of membrane forming lipids, molecular dynamics simulations, and absorbance spectroscopy revealed the possibility of direct interactions between AmB and some flavones in the water and/or in the lipid bilayer. The influence of these interactions on the antibiotic partitioning between aqueous solution and membrane and/or its transition between different states in the bilayer was discussed.

Multifunctional Nanocarriers for Alzheimer's Disease: Befriending the Barriers

Neurodegenerative diseases (NDDs) have been increasing in incidence in recent years and are now widespread worldwide. Neuronal death is defined as the progressive loss of neuronal structure or function which is closely associated with NDDs and represents the intrinsic features of such disorders. Amyotrophic lateral sclerosis, frontotemporal dementia, Alzheimer's, Parkinson's, and Huntington's diseases (AD, PD, and HD, respectively) are considered neurodegenerative diseases that affect a large number of people worldwide. Despite the testing of various drugs, there is currently no available therapy that can remedy or effectively slow the progression of these diseases. Nanomedicine has the potential to revolutionize drug delivery for the management of NDDs. The use of nanoparticles (NPs) has recently been developed to improve drug delivery efficiency and is currently subjected to extensive studies. Nanoengineered particles, known as nanodrugs, can cross the blood-brain barrier while also being less invasive compared to the most treatment strategies in use. Polymeric, magnetic, carbonic, and inorganic NPs are examples of NPs that have been developed to improve drug delivery efficiency. Primary research studies using NPs to cure AD are promising, but thorough research is needed to introduce these approaches to clinical use. In the present review, we discussed the role of metal-based NPs, polymeric nanogels, nanocarrier systems such as liposomes, solid lipid NPs, polymeric NPs, exosomes, quantum dots, dendrimers, polymersomes, carbon nanotubes, and nanofibers and surfactant-based systems for the therapy of neurodegenerative diseases. In addition, we highlighted nanoformulations such as N-butyl cyanoacrylate, poly(butyl cyanoacrylate), D-penicillamine, citrate-coated peptide, magnetic iron oxide, chitosan (CS), lipoprotein, ceria, silica, metallic nanoparticles, cholinesterase inhibitors, an acetylcholinesterase inhibitors, metal chelators, anti-amyloid, protein, and peptide-loaded NPs for the treatment of AD.

Stepwise targeted strategies for improving neurological function by inhibiting oxidative stress levels and inflammation following ischemic stroke

Ischemia-reperfusion injury is caused by excessive production of reactive oxygen species (ROS) and inflammation accompanied by ischemic injury symptoms and blood-brain barrier (BBB) dysfunction. This causes neuronal damage, for which no effective treatments or drugs exist. Herein, we provided a stepwise targeted drug delivery strategy and successfully prepared multifunctional ORD@SHp@ANG nanoparticles (NPs) that consist of a stroke homing peptide (DSPE-PEG2000-SHp), BBB-targeting peptide (DSPE-PEG2000-ANG), and ROS-responsive Danshensu (salvianic acid A) chain self-assembly. ORD@SHp@ANG NPs effectively crossed the BBB by ANG peptide and selectively targeted the ischemic brain sites using stroke-homing peptide. The results showed that ORD@SHp@ANG NPs can effective at scavenging ROS, and protect SH-SY5Y cells from oxidative damage in vitro. Furthermore, ORD@SHp@ANG NPs showed excellent biocompatibility. These NPs recognized brain endothelial cells and crossed the BBB, regulated the transformation of microglia into the anti-inflammatory phenotype, and inhibited the production of inflammatory factors in a rat ischemia-reperfusion model, thereby reducing cerebral infarction, neuronal apoptosis and preserving BBB integrity. Sequencing revealed that ORD@SHp@ANG NPs promote cell proliferation, activate immune responses, suppress inflammatory responses, and ameliorate ischemic stroke. In conclusion, this study reports a simple and promising drug delivery strategy for managing ischemic stroke.

Enhancing paracellular and transcellular permeability using nanotechnological approaches for the treatment of brain and retinal diseases

Paracellular permeability across epithelial and endothelial cells is, in large part, regulated by apical intercellular junctions also referred to as tight junctions (TJs). These junctions contribute to the spatial definition of different tissue compartments within organisms, separating them from the outside world as well as from inner compartments, with their primary physiological role of maintaining tissue homeostasis. TJs restrict the free, passive diffusion of ions and hydrophilic small molecules through paracellular clefts and are important for appropriate cell polarization and transporter protein localisation, supporting the controlled transcellular diffusion of smaller and larger hydrophilic as well as hydrophobic substances. This traditional diffusion barrier concept of TJs has been challenged lately, owing to a better understanding of the components that are associated with TJs. It is now well-established that mutations in TJ proteins are associated with a range of human diseases and that a change in the membrane fluidity of neighbouring cells can open possibilities for therapeutics to cross intercellular junctions. Nanotechnological approaches, exploiting ultrasound or hyperosmotic agents and permeation enhancers, are the paradigm for achieving enhanced paracellular diffusion. The other widely used transport route of drugs is via transcellular transport, allowing the passage of a variety of pro-drugs and nanoparticle-encapsulated drugs via different mechanisms based on receptors and others. For a long time, there was an expectation that lipidic nanocarriers and polymeric nanostructures could revolutionize the field for the delivery of RNA and protein-based therapeutics across different biological barriers equipped with TJs (e.g., blood-brain barrier (BBB), retina-blood barrier (RBB), corneal TJs, etc.). However, only a limited increase in therapeutic efficiency has been reported for most systems until now. The purpose of this review is to explore the reasons behind the current failures and to examine the emergence of synthetic and cell-derived nanomaterials and nanotechnological approaches as potential game-changers in enhancing drug delivery to target locations both at and across TJs using innovative concepts. Specifically, we will focus on recent advancements in various nanotechnological strategies enabling the bypassing or temporally opening of TJs to the brain and to the retina, and discuss their advantages and limitations.

Dendritic hybrid materials comprising polyhedral oligomeric silsesquioxane (POSS) and hyperbranched polyglycerol for effective antifungal drug delivery and therapy in systemic candidiasis

Systemic Candida infections are routinely treated with amphotericin B (AMB), a highly effective antimycotic drug. However, due to severe toxicities linked to the parenteral administration of conventional micellar formulations (Fungizone®), its clinical utility is limited. Hyperbranched polyglycerols (HPGs) are multi-branched three-dimensional hydrophilic macromolecules that can be used to lessen the toxicity of AMB while also increasing its aqueous solubility. In the current research, to improve the safety and therapeutic efficacy of AMB, we developed new polyhedral oligomeric silsesquioxane - hyperbranched polyglycerol dendrimers with cholesterol termini (POSS-HPG@Chol) using azide-alkyne click reaction. Compared with Fungizone®, the as-synthesized POSS-HPG@Chol/AMB had lower minimum inhibitory and fungicidal concentrations against almost all studied Candida spp., as well as much less hemolysis and cytotoxicity. POSS-HPG@Chol/AMB revealed total protection of Balb/C mice from severe Candida infections in an experimental model of systemic candidiasis and can effectively reduce or eliminate AMB liver and kidney tissue injuries. Thanks to their safety, biocompatibility, and unique therapeutic properties, the developed POSS-polyglycerol dendrimers could be viable nanostructures for the delivery of poorly soluble drugs like AMB.

Biological interactions of polystyrene nanoplastics: Their cytotoxic and immunotoxic effects on the hepatic and enteric systems

As emerging pollutants in the environment, nanoplastics (NPs) can cross biological barriers and be enriched in organisms, posing a greatest threat to the health of livestock and humans. However, the size-dependent toxic effects of NPs in higher mammals remain largely unknown. To determine the size-dependent potential toxicities of NPs, we exposed mouse (AML-12) and human (L02) liver cell lines in vitro, and 6-week-old C57BL/6 mice (well-known preclinical model) in vivo to five different sizes of polystyrene NPs (PS-NPs) (20, 50, 100, 200 and 500 nm). We found that ultra-small NPs (20 nm) induced the highest cytotoxicity in mouse and human liver cell lines, causing oxidative stress and mitochondrial membrane potential loss on AML-12 cells. Unexpectedly in vivo, after long-term oral exposure to PS-NPs (75 mg/kg), medium NPs (200 nm) and large NPs (500 nm) induced significant hepatotoxicity, evidenced by increased oxidative stress, liver dysfunction, and lipid metabolism disorders. Most importantly, medium or large NPs generated local immunotoxic effects via recruiting and activating more numbers of neutrophils and monocytes in the liver or intestine, which potentially resulted in increased proinflammatory cytokine secretion and the tissue damage. The discrepancy in in vitro-in vivo toxic results might be attributed to the different properties of biodistribution and tissue accumulation of different sized NPs in vivo. Our study provides new insights regarding the hepatotoxicity and immunotoxicity of NPs on human and livestock health, warranting us to take immense measures to prevent these NPs-associated health damage.

Antifungal therapy: Novel drug delivery strategies driven by new targets

In patients with compromised immunity, invasive fungal infections represent a significant cause of mortality. Given the limited availability and drawbacks of existing first-line antifungal drugs, there is a growing interest in exploring novel targets that could facilitate the development of new antifungal agents or enhance the effectiveness of conventional ones. While previous studies have extensively summarized new antifungal targets inherent in fungi for drug development purposes, the exploration of potential targets for novel antifungal drug delivery strategies has received less attention. In this review, we provide an overview of recent advancements in new antifungal drug delivery strategies that leverage novel targets, including those located in the physio-pathological barrier at the site of infection, the infection microenvironment, fungal-host interactions, and the fungal pathogen itself. The objective is to enhance therapeutic efficacy and mitigate toxic effects in fungal infections, particularly in challenging cases such as refractory, recurrent, and drug-resistant invasive fungal infections. We also discuss the current challenges and future prospects associated with target-driven antifungal drug delivery strategies, offering important insights into the clinical implementation of these innovative approaches.

Advances in anti-invasive fungal drug delivery systems

Currently, the first-line drugs for invasive fungal infections (IFI), such as amphotericin B, fluconazole and itraconazole, have drawbacks including poor water solubility, low bioavailability, and severe side effects. Using drug delivery systems is a promising strategy to improve the efficacy and safety of traditional antifungal therapy. Synthetic and biomimetic carriers have greatly facilitated the development of targeted delivery systems for antifungal drugs. Synthetic carrier drug delivery systems, such as liposomes, nanoparticles, polymer micelles, and microspheres, can improve the physicochemical properties of antifungal drugs, prolong their circulation time, enhance targeting capabilities, and reduce toxic side effects. Cell membrane biomimetic drug delivery systems, such as macrophage or red blood cell membrane-coated drug delivery systems, retain the membrane structure of somatic cells and confer various biological functions and specific targeting abilities to the loaded antifungal drugs, exhibiting better biocompatibility and lower toxicity. This article reviews the development of antifungal drug delivery systems and their application in the treatment of IFI, and also discusses the prospects of novel biomimetic carriers in antifungal drug delivery.

CD44-Targeted Lipid Polymer Hybrid Nanoparticles Enhance Anti-Breast Cancer Effect of Cordyceps militaris Extracts

This study aimed to improve the anticancer effect of Cordyceps militaris herbal extract (CME) on breast cancer cells with hyaluronic acid (HYA) surface-decorated lipid polymer hybrid nanoparticles (LPNPs) and evaluate the applicability of a synthesized poly(glycerol adipate) (PGA) polymer for LPNP preparation. Firstly, cholesterol- and vitamin E-grafted PGA polymers (PGA-CH and PGA-VE, respectively) were fabricated, with and without maleimide-ended polyethylene glycol. Subsequently, CME, which contained an active cordycepin equaling 9.89% of its weight, was encapsulated in the LPNPs. The results revealed that the synthesized polymers could be used to prepare CME-loaded LPNPs. The LPNP formulations containing Mal-PEG were decorated with cysteine-grafted HYA via thiol-maleimide reactions. The HYA-decorated PGA-based LPNPs substantially enhanced the anticancer effect of CME against MDA-MB-231 and MCF-7 breast cancer cells by enhancing cellular uptake through CD44 receptor-mediated endocytosis. This study demonstrated the successful targeted delivery of CME to the CD44 receptors of tumor cells by HYA-conjugated PGA-based LPNPs and the new application of synthesized PGA-CH- and PGA-VE-based polymers in LPNP preparation. The developed LPNPs showed promising potential for the targeted delivery of herbal extracts for cancer treatment and clear potential for translation in in vivo experiments.

Passing of Nanocarriers across the Histohematic Barriers: Current Approaches for Tumor Theranostics

Over the past several decades, nanocarriers have demonstrated diagnostic and therapeutic (i.e., theranostic) potencies in translational oncology, and some agents have been further translated into clinical trials. However, the practical application of nanoparticle-based medicine in living organisms is limited by physiological barriers (blood-tissue barriers), which significantly hampers the transport of nanoparticles from the blood into the tumor tissue. This review focuses on several approaches that facilitate the translocation of nanoparticles across blood-tissue barriers (BTBs) to efficiently accumulate in the tumor. To overcome the challenge of BTBs, several methods have been proposed, including the functionalization of particle surfaces with cell-penetrating peptides (e.g., TAT, SynB1, penetratin, R8, RGD, angiopep-2), which increases the passing of particles across tissue barriers. Another promising strategy could be based either on the application of various chemical agents (e.g., efflux pump inhibitors, disruptors of tight junctions, etc.) or physical methods (e.g., magnetic field, electroporation, photoacoustic cavitation, etc.), which have been shown to further increase the permeability of barriers.

Engineering Telodendrimer Nanocarriers for Monomeric Amphotericin B Delivery

Systemic fungal infections are an increasingly prevalent health problem. Amphotericin B (AmB), a hydrophobic polyene antibiotic, remains the drug of choice for life-threatening invasive fungal infections. However, it has dose-limiting side effects, including nephrotoxicity. The efficacy and toxicity of AmB are directly related to its aggregation state. Here, we report the preparation of a series of telodendrimer (TD) nanocarriers with the freely engineered core structures for AmB encapsulation to fine-tune AmB aggregation status. The reduced aggregation status correlates well with the optimized antifungal activity, attenuated hemolytic properties, and reduced cytotoxicity to mammalian cells. The optimized TD nanocarrier for monomeric AmB encapsulation significantly increases the therapeutic index, reduces the in vivo toxicity, and enhances antifungal effects in mouse models with Candida albicans infection in comparison to two common clinical formulations, i.e., Fungizone and AmBisome.

Influence of the Drug Position on Bioactivity in Angiopep-2-Daunomycin Conjugates

The blood-brain barrier (BBB) is a semipermeable system, and, therefore, most of the active substances are poorly transported through this barrier, resulting in decreased therapeutic effects. Angiopep-2 (TFFYGGSRGKRNNFKTEEY) is a peptide ligand of low-density lipoprotein receptor-related protein-1 (LRP1), which can cross the BBB via receptor-mediated transcytosis and simultaneously target glioblastomas. Angiopep-2 contains three amino groups that have previously been used to produce drug-peptide conjugates, although the role and importance of each position have not yet been investigated. Thus, we studied the number and position of drug molecules in Angiopep-2 based conjugates. Conjugates containing one, two, and three daunomycin molecules conjugated via oxime linkage in all possible variations were prepared. The in vitro cytostatic effect and cellular uptake of the conjugates were investigated on U87 human glioblastoma cells. Degradation studies in the presence of rat liver lysosomal homogenates were also performed in order for us to better understand the structure-activity relationship and to determine the smallest metabolites. Conjugates with the best cytostatic effects had a drug molecule at the N-terminus. We demonstrated that the increasing number of drug molecules does not necessarily increase the efficacy of the conjugates, and proved that modification of the different conjugation sites results in differing biological effectiveness.

Neuro-nanotechnology: diagnostic and therapeutic nano-based strategies in applied neuroscience

Artificial, de-novo manufactured materials (with controlled nano-sized characteristics) have been progressively used by neuroscientists during the last several decades. The introduction of novel implantable bioelectronics interfaces that are better suited to their biological targets is one example of an innovation that has emerged as a result of advanced nanostructures and implantable bioelectronics interfaces, which has increased the potential of prostheses and neural interfaces. The unique physical-chemical properties of nanoparticles have also facilitated the development of novel imaging instruments for advanced laboratory systems, as well as intelligently manufactured scaffolds and microelectrodes and other technologies designed to increase our understanding of neural tissue processes. The incorporation of nanotechnology into physiology and cell biology enables the tailoring of molecular interactions. This involves unique interactions with neurons and glial cells in neuroscience. Technology solutions intended to effectively interact with neuronal cells, improved molecular-based diagnostic techniques, biomaterials and hybridized compounds utilized for neural regeneration, neuroprotection, and targeted delivery of medicines as well as small chemicals across the blood-brain barrier are all purposes of the present article.

Current approaches to facilitate improved drug delivery to the central nervous system

Although many pharmaceuticals have therapeutic potentials for central nervous system (CNS) diseases, few of these agents have been effectively administered. It is due to the fact that the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSF) restrict them from crossing the brain to exert biological activity. This article reviews the current approaches aiming to improve penetration across these barriers for effective drug delivery to the CNS. These issues are summarized into direct systemic delivery and invasive delivery, including the BBB disruption and convection enhanced delivery. Furthermore, novel drug delivery systems used at the nanoscale, including polymeric nanoparticles, liposomes, nanoemulsions, dendrimers, and micelles are discussed. These nanocarriers could contribute to a breakthrough in the treatment of many different CNS diseases. However, further broadened studies are needed to assess the biocompatibility and safety of these medical devices.

Targeted delivery of nanomedicines for promoting vascular regeneration in ischemic diseases

Ischemic diseases, the leading cause of disability and death, are caused by the restriction or blockage of blood flow in specific tissues, including ischemic cardiac, ischemic cerebrovascular and ischemic peripheral vascular diseases. The regeneration of functional vasculature network in ischemic tissues is essential for treatment of ischemic diseases. Direct delivery of pro-angiogenesis factors, such as VEGF, has demonstrated the effectiveness in ischemic disease therapy but suffering from several obstacles, such as low delivery efficacy in disease sites and uncontrolled modulation. In this review, we summarize the molecular mechanisms of inducing vascular regeneration, providing the guidance for designing the desired nanomedicines. We also introduce the delivery of various nanomedicines to ischemic tissues by passive or active targeting manner. To achieve the efficient delivery of nanomedicines in various ischemic diseases, we highlight targeted delivery of nanomedicines and controllable modulation of disease microenvironment using nanomedicines.

Peptides as Pharmacological Carriers to the Brain: Promises, Shortcomings and Challenges

Central nervous system (CNS) diseases are among the most difficult to treat, mainly because the vast majority of the drugs fail to cross the blood-brain barrier (BBB) or to reach the brain at concentrations adequate to exert a pharmacological activity. The obstacle posed by the BBB has led to the in-depth study of strategies allowing the brain delivery of CNS-active drugs. Among the most promising strategies is the use of peptides addressed to the BBB. Peptides are versatile molecules that can be used to decorate nanoparticles or can be conjugated to drugs, with either a stable link or as pro-drugs. They have been used to deliver to the brain both small molecules and proteins, with applications in diverse therapeutic areas such as brain cancers, neurodegenerative diseases and imaging. Peptides can be generally classified as receptor-targeted, recognizing membrane proteins expressed by the BBB microvessels (e.g., Angiopep2, CDX, and iRGD), "cell-penetrating peptides" (CPPs; e.g. TAT_47-57, SynB1/3, and Penetratin), undergoing transcytosis through unspecific mechanisms, or those exploiting a mixed approach. The advantages of peptides have been extensively pointed out, but so far few studies have focused on the potential negative aspects. Indeed, despite having a generally good safety profile, some peptide conjugates may display toxicological characteristics distinct from those of the peptide itself, causing for instance antigenicity, cardiovascular alterations or hemolysis. Other shortcomings are the often brief lifetime in vivo, caused by the presence of peptidases, the vulnerability to endosomal/lysosomal degradation, and the frequently still insufficient attainable increase of brain drug levels, which remain below the therapeutically useful concentrations. The aim of this review is to analyze not only the successful and promising aspects of the use of peptides in brain targeting but also the problems posed by this strategy for drug delivery.

An update on dual targeting strategy for cancer treatment

The key issue in the treatment of solid tumors is the lack of efficient strategies for the targeted delivery and accumulation of therapeutic cargoes in the tumor microenvironment (TME). Targeting approaches are designed for more efficient delivery of therapeutic agents to cancer cells while minimizing drug toxicity to normal cells and off-targeting effects, while maximizing the eradication of cancer cells. The highly complicated interrelationship between the physicochemical properties of nanoparticles, and the physiological and pathological barriers that are required to cross, dictates the need for the success of targeting strategies. Dual targeting is an approach that uses both purely biological strategies and physicochemical responsive smart delivery strategies to increase the accumulation of nanoparticles within the TME and improve targeting efficiency towards cancer cells. In both approaches, either one single ligand is used for targeting a single receptor on different cells, or two different ligands for targeting two different receptors on the same or different cells. Smart delivery strategies are able to respond to triggers that are typical of specific disease sites, such as pH, certain specific enzymes, or redox conditions. These strategies are expected to lead to more precise targeting and better accumulation of nano-therapeutics. This review describes the classification and principles of dual targeting approaches and critically reviews the efficiency of dual targeting strategies, and the rationale behind the choice of ligands. We focus on new approaches for smart drug delivery in which synthetic and/or biological moieties are attached to nanoparticles by TME-specific responsive linkers and advanced camouflaged nanoparticles.

Strategies for Targeted Delivery of Exosomes to the Brain: Advantages and Challenges

Delivering therapeutics to the central nervous system (CNS) is difficult because of the blood-brain barrier (BBB). Therapeutic delivery across the tight junctions of the BBB can be achieved through various endogenous transportation mechanisms. Receptor-mediated transcytosis (RMT) is one of the most widely investigated and used methods. Drugs can hijack RMT by expressing specific ligands that bind to receptors mediating transcytosis, such as the transferrin receptor (TfR), low-density lipoprotein receptor (LDLR), and insulin receptor (INSR). Cell-penetrating peptides and viral components originating from neurotropic viruses can also be utilized for the efficient BBB crossing of therapeutics. Exosomes, or small extracellular vesicles, have gained attention as natural nanoparticles for treating CNS diseases, owing to their potential for natural BBB crossing and broad surface engineering capability. RMT-mediated transport of exosomes expressing ligands such as LDLR-targeting apolipoprotein B has shown promising results. Although surface-modified exosomes possessing brain targetability have shown enhanced CNS delivery in preclinical studies, the successful development of clinically approved exosome therapeutics for CNS diseases requires the establishment of quantitative and qualitative methods for monitoring exosomal delivery to the brain parenchyma in vivo as well as elucidation of the mechanisms underlying the BBB crossing of surface-modified exosomes.

Angiopep-2-Modified Nanoparticles for Brain-Directed Delivery of Therapeutics: A Review

Nanotechnology has opened up a world of possibilities for the treatment of brain disorders. Nanosystems can be designed to encapsulate, carry, and deliver a variety of therapeutic agents, including drugs and nucleic acids. Nanoparticles may also be formulated to contain photosensitizers or, on their own, serve as photothermal conversion agents for phototherapy. Furthermore, nano-delivery agents can enhance the efficacy of contrast agents for improved brain imaging and diagnostics. However, effective nano-delivery to the brain is seriously hampered by the formidable blood-brain barrier (BBB). Advances in understanding natural transport routes across the BBB have led to receptor-mediated transcytosis being exploited as a possible means of nanoparticle uptake. In this regard, the oligopeptide Angiopep-2, which has high BBB transcytosis capacity, has been utilized as a targeting ligand. Various organic and inorganic nanostructures have been functionalized with Angiopep-2 to direct therapeutic and diagnostic agents to the brain. Not only have these shown great promise in the treatment and diagnosis of brain cancer but they have also been investigated for the treatment of brain injury, stroke, epilepsy, Parkinson's disease, and Alzheimer's disease. This review focuses on studies conducted from 2010 to 2021 with Angiopep-2-modified nanoparticles aimed at the treatment and diagnosis of brain disorders.

Low-Level Endothelial TRAIL-Receptor Expression Obstructs the CNS-Delivery of Angiopep-2 Functionalised TRAIL-Receptor Agonists for the Treatment of Glioblastoma

Glioblastoma (GBM) is the most malignant and aggressive form of glioma and is associated with a poor survival rate. Latest generation Tumour Necrosis Factor Related Apoptosis-Inducing Ligand (TRAIL)-based therapeutics potently induce apoptosis in cancer cells, including GBM cells, by binding to death receptors. However, the blood-brain barrier (BBB) is a major obstacle for these biologics to enter the central nervous system (CNS). We therefore investigated if antibody-based fusion proteins that combine hexavalent TRAIL and angiopep-2 (ANG2) moieties can be developed, with ANG2 promoting receptor-mediated transcytosis (RMT) across the BBB. We demonstrate that these fusion proteins retain the potent apoptosis induction of hexavalent TRAIL-receptor agonists. Importantly, blood-brain barrier cells instead remained highly resistant to this fusion protein. Binding studies indicated that ANG2 is active in these constructs but that TRAIL-ANG2 fusion proteins bind preferentially to BBB endothelial cells via the TRAIL moiety. Consequently, transport studies indicated that TRAIL-ANG2 fusion proteins can, in principle, be shuttled across BBB endothelial cells, but that low TRAIL receptor expression on BBB endothelial cells interferes with efficient transport. Our work therefore demonstrates that TRAIL-ANG2 fusion proteins remain highly potent in inducing apoptosis, but that therapeutic avenues will require combinatorial strategies, such as TRAIL-R masking, to achieve effective CNS transport.

Polymeric Nanoparticles Properties and Brain Delivery

Safe and reliable entry to the brain is essential for successful diagnosis and treatment of diseases, but it still poses major challenges. As a result, many therapeutic approaches to treating disorders associated with the central nervous system (CNS) still only show limited success. Nano-sized systems are being explored as drug carriers and show great improvements in the delivery of many therapeutics. The systemic delivery of nanoparticles (NPs) or nanocarriers (NCs) to the brain involves reaching the neurovascular unit (NVU), being transported across the blood-brain barrier, (BBB) and accumulating in the brain. Each of these steps can benefit from specifically controlled properties of NPs. Here, we discuss how brain delivery by NPs can benefit from careful design of the NP properties. Properties such as size, charge, shape, and ligand functionalization are commonly addressed in the literature; however, properties such as ligand density, linker length, avidity, protein corona, and stiffness are insufficiently discussed. This is unfortunate since they present great value against multiple barriers encountered by the NPs before reaching the brain, particularly the BBB. We further highlight important examples utilizing targeting ligands and how functionalization parameters, e.g., ligand density and ligand properties, can affect the success of the nano-based delivery system.

Nanoparticles for Targeted Brain Drug Delivery: What Do We Know?

The blood-brain barrier (BBB) is a barrier that separates the blood from the brain tissue and possesses unique characteristics that make the delivery of drugs to the brain a great challenge. To achieve this purpose, it is necessary to design strategies to allow BBB passage, in order to reach the brain and target the desired anatomic region. The use of nanomedicine has great potential to overcome this problem, since one can modify nanoparticles with strategic molecules that can interact with the BBB and induce uptake through the brain endothelial cells and consequently reach the brain tissue. This review addresses the potential of nanomedicines to treat neurological diseases by using nanoparticles specially developed to cross the BBB.

Sub-50 nm ultra-small organic drug nanosuspension prepared by cavi-precipitation and its brain targeting potential

The purpose of this study was to show whether it is possible to prepare sub 100 nm or preferably sub-50 nm drug nanosuspension (NS) of suitable quality for intravenous administration. Furthermore, we have studied how the brain targeting potential of such small size organic NS differs from relatively bigger size NS. Two combination technologies (cavi-precipitation, H96) and a standard high-pressure homogenization (HPH) technology were used to prepare drug NS of different sizes. The cavi-precipitation process generated the smallest AmB NS, i.e., 27 nm compared to 79 nm by H96 technology and 252 nm by standard HPH technology. Dialysis of the nanosuspension in the original dispersion media was found to be the most efficient solvent removal method without negatively affecting particle size. The removal of organic solvent was found to drastically improve the stability of the formulations. The protein adsorption pattern shows that the small size NS particles obtained by the cavi-precipitation process have the potential to circulate longer in the bloodstream and have the potential to be taken up by the blood-brain barrier. The cavi-precipitation process generated ultrafine NS particles, which fulfilled the quality requirements for intravenous administration and offer a potential solution for brain targeting.

Nanoparticles and nanoformulated drugs as promising delivery system in treatment of microbial-induced CNS infection: a systematic review of literature

Central nervous system (CNS) infection is a global health problem with high rate of mortality and associated morbidities. Viruses, bacteria, fungi, and protozoa parasites are the main cause of CNS infection. Various medications are currently used for treatment of brain infections, but most of them do not have enough efficiency because the majority of conventional drugs cannot pass the blood-brain barrier (BBB) to combat the pathogens. Nanotechnology has provided promising approaches to solve this issue, since nanoparticles (NPs) can facilitate the drugs entrance through the BBB. Herein, we systematically reviewed all available literature to provide evidences for practicality of NPs in treatment of CNS infection. A systematic literature search was performed on January 29, 2021, in Web of Science, PubMed, Scopus, Science Direct, Embase, Ovid, and Google Scholar using "CNS infections" and "NPs/nanoformulation" including all their equivalent terms as keyword. Due to lack of human studies, no strict inclusion criteria were defined, and all relevant documents were included. After several steps of article selection, a total of 29 documents were collected and used for data synthesis. The results showed that drug-loaded NPs is fairly safe and can be a promising approach in developing anti-infective agents for treatment of CNS infection, since nanoformulated drugs could act up to tenfold more efficient that drug alone. Findings of this review indicate the importance of NPs and nanoformulation of drugs to enhance the efficiency of treatment and warrant the safety of treatment in human studies; however, clinical trials are required to confirm such efficiency and safety in clinical practice.

Development of Polymeric Nanoparticles for Blood-Brain Barrier Transfer-Strategies and Challenges

Neurological disorders such as Alzheimer's disease, stroke, and brain cancers are difficult to treat with current drugs as their delivery efficacy to the brain is severely hampered by the presence of the blood-brain barrier (BBB). Drug delivery systems have been extensively explored in recent decades aiming to circumvent this barrier. In particular, polymeric nanoparticles have shown enormous potentials owing to their unique properties, such as high tunability, ease of synthesis, and control over drug release profile. However, careful analysis of their performance in effective drug transport across the BBB should be performed using clinically relevant testing models. In this review, polymeric nanoparticle systems for drug delivery to the central nervous system are discussed with an emphasis on the effects of particle size, shape, and surface modifications on BBB penetration. Moreover, the authors critically analyze the current in vitro and in vivo models used to evaluate BBB penetration efficacy, including the latest developments in the BBB-on-a-chip models. Finally, the challenges and future perspectives for the development of polymeric nanoparticles to combat neurological disorders are discussed.

Challenge to overcome current limitations of cell-penetrating peptides

The penetration of biological membranes is a prime obstacle for the delivery of pharmaceutical drugs. Cell-penetrating peptide (CPP) is an efficient vehicle that can deliver various cargos across the biological membranes. Since the discovery, CPPs have been rigorously studied to unveil the underlying penetrating mechanism as well as to exploit CPPs for various biomedical applications. This review will focus on the various strategies to overcome current limitations regarding stability, selectivity, and efficacy of CPPs.

Progress in the Application of Nanoparticles and Graphene as Drug Carriers and on the Diagnosis of Brain Infections

The blood–brain barrier (BBB) is the protective sheath around the brain that protects the sensitive microenvironments of the brain. However, certain pathogens, viruses, and bacteria disrupt the endothelial barrier and cause infection and hence inflammation in meninges. Macromolecular therapeutics are unable to cross the tight junctions, thereby limiting their bioavailability in the brain. Recently, nanotechnology has brought a revolution in the field of drug delivery in brain infections. The nanostructures have high targeting accuracy and specificity to the receptors in the case of active targeting, which have made them the ideal cargoes to permeate across the BBB. In addition, nanomaterials with biomimetic functions have been introduced to efficiently cross the BBB to be engulfed by the pathogens. This review focuses on the nanotechnology-based drug delivery approaches for exploration in brain infections, including meningitis. Viruses, bacteria, fungi, or, rarely, protozoa or parasites may be the cause of brain infections. Moreover, inflammation of the meninges, called meningitis, is presently diagnosed using laboratory and imaging tests. Despite attempts to improve diagnostic instruments for brain infections and meningitis, due to its complicated and multidimensional nature and lack of successful diagnosis, meningitis appears almost untreatable. Potential for overcoming the difficulties and limitations related to conventional diagnostics has been shown by nanoparticles (NPs). Nanomedicine now offers new methods and perspectives to improve our knowledge of meningitis and can potentially give meningitis patients new hope. Here, we review traditional diagnosis tools and key nanoparticles (Au-NPs, graphene, carbon nanotubes (CNTs), QDs, etc.) for early diagnosis of brain infections and meningitis.

Small functionalized iron oxide nanoparticles for dual brain magnetic resonance imaging and fluorescence imaging

SIONs is modified with brain targeting ligands and photosensitizers, and is used for in vivo MR/FL dual-mode high-sensitivity brain imaging.

Novel Phospholipid-Based Labrasol Nanomicelles Loaded Flavonoids for Oral Delivery with Enhanced Penetration and Anti-Brain Tumor Efficiency

BACKGROUND

Owing to the rich anticancer properties of flavonoids, there is a need for their incorporation into drug delivery vehicles like nanomicelles for safe delivery of the drug into the brain tumor microenvironment.

OBJECTIVE

This study, therefore, aimed to prepare the phospholipid-based Labrasol/Pluronic F68 modified nano micelles loaded with flavonoids (Nano-flavonoids) for the delivery of the drug to the target brain tumor.

METHODS

Myricetin, quercetin and fisetin were selected as the initial drugs to evaluate the biodistribution and acute toxicity of the drug delivery vehicles in rats with implanted C6 glioma tumors after oral administration, while the uptake, retention, release in human intestinal Caco-2 cells and the effect on the brain endothelial barrier were investigated in Human Brain Microvascular Endothelial Cells (HBMECs).

RESULTS

The results demonstrated that nano-flavonoids loaded with myricetin showed more evenly distributed targeting tissues and enhanced anti-tumor efficiency in vivo without significant cytotoxicity to Caco-2 cells and alteration in the Trans Epithelial Electric Resistance (TEER). There was no pathological evidence of renal, hepatic or other organs dysfunction after the administration of nanoflavonoids, which showed no significant influence on cytotoxicity to Caco-2 cells.

CONCLUSION

In conclusion, Labrasol/F68-NMs loaded with MYR and quercetin could enhance antiglioma effect in vitro and in vivo, which may be better tools for medical therapy, while the pharmacokinetics and pharmacodynamics of nano-flavonoids may ensure optimal therapeutic benefits.

Amphotericin B loaded ethyl cellulose nanoparticles with magnified oral bioavailability for safe and effective treatment of fungal infection

Amphotericin B is a gold standard drug used in various fungal and parasitic infection treatment. Most of the marketed formulations are administered intravenously, but show dose-dependent adverse effects i.e., nephrotoxicity and hemolysis. Oral route eliminates the toxic concern but exhibits poor bioavailability. Therefore, ethylcellulose nanoparticles (EC-NPs) have been used for magnified oral delivery of AmB, where EC provides gastrointestinal stability. These nanoparticles were synthesized by high-pressure emulsification solvent evaporation (HPESE) method and evaluated for in vitro and in vivo studies. This method yields small, monodisperse AmB-EC-NPs along with smooth surface morphology and improved encapsulation efficiency. The developed formulation showed a sustained release pattern following Higuchi diffusion kinetics along with gastric and storage stability. Aggregation study revealed that AmB was present in its monomeric form inside the biocompatible EC matrix. The antifungal result demonstrated that the MIC of AmB-EC-NPs was reduced ∼1/3rd than AmB and Fungizone® at 24 h whereas it was observed ∼1/8th at 48 h. in vivo pharmacokinetic analysis demonstrated 1.3-fold higher AUC than Fungizone® even at a 4.5-time lesser dose via the oral route and a ∼15-fold rise in the bioavailability in contrast to the native AmB. The hemolytic study revealed that the developed formulation exhibited 8-fold lesser hemolysis than Fungizone®. Furthermore, the biosafety profile of AmB-EC-NPs was ensured by the significantly lesser level of blood urea nitrogen and plasma creatinine along with the normal pattern of renal tubules in comparison to AmB and Fungizone®. In conclusion, the results stipulated that the AmB-EC-NPs could be effective, viable and a better alternative to currently existing iv formulations, for magnified oral delivery of AmB in the treatment of fungal infection without associated adverse effects.

Turning weakness into strength: Albumin nanoparticle-redirected amphotericin B biodistribution for reducing nephrotoxicity and enhancing antifungal activity

As the gold standard treatment for invasive fungal infection, amphotericin B (AmB) is limited by its severe nephrotoxicity. It has been shown that AmB complex with albumin in vivo forms a sub-10 nm nanocomplex within kidney excretion size range and eventually induces the nephrotoxicity. This study presents an approach to take advantage of the "weakness" of such unique interaction between AmB and albumin to form AmB nanocomplex beyond the size range of kidney excretion. Herein, a novel strategy was developed by directly assembling molecular BSA into larger-sized nanostructures with the reconstructed intermolecular disulfide bond and hydrophobic interaction. The rich binding sites of AmB within BSA nanostructures enabled the efficient AmB loading and forming nanoparticle (AmB-NP) which exceeds the size range of kidney excretion (~ 60 nm). We found nanoassembly with BSA redirected biodistribution of AmB with a 2.8-fold reduction of drug accumulation in the kidney and significantly improved its renal impairment in mice. Furthermore, we found that nanoassembly with BSA significantly increased the biodistribution of AmB in brain and endowed it 100-folds increase in pharmacological effect against meningoencephalitis caused by common fungal pathogen Cryptococcus neoformans. Together, this study not merely overcomes the nephrotoxicity of AmB using its "weakness" by a nanoassembly method, and provides a new strategy for reducing toxicity of drugs with high albumin binding rate in vivo.