Cationic albumin-conjugated pegylated nanoparticles as novel drug carrier for brain delivery

Advancements in nanotheranostics for glioma therapy

Gliomas are brain tumors mainly derived from glial cells that are difficult to treat and cause high mortality. Radiation, chemotherapy, and surgical excision are the conventional treatments for gliomas. Patients who have surgery or have undergone chemotherapy for glioma treatment have poor prognosis with tumor recurrence. In particular, for glioblastoma, the 5-year average survival rate is 4-7%, and the median survival is 12-18 months. A number of issues hinder effective treatment such as, poor surgical resection, tumor heterogeneity, insufficient drug penetration across the blood-brain barrier, multidrug resistance, and difficulties with drug specificity. Nanotheranostic-mediated drug delivery is becoming a well-researched consideration, and an efficient non-invasive method for delivering chemotherapeutic drugs to the target area. Theranostic nanomedicines, which incorporate therapeutic drugs and imaging agents for personalized therapies, can be used for preventing overdose of non-responders. Through the identification of massive and complicated information from next-generation sequencing, machine learning enables for precise prediction of therapeutic outcomes and post-treatment management for patients with cancer. This article gives a thorough overview of nanocarrier-mediated drug delivery with a brief introduction to drug delivery challenges. In addition, this assessment offers a current summary of preclinical and clinical research on nanomedicines for gliomas. In the future, nanotheranostics will provide personalized treatment for gliomas and other treatable cancers.

Glycocalyx Interactions Modulate the Cellular Uptake of Albumin-Coated Nanoparticles

Albumin-based nanoparticles (ABNPs) represent promising drug carriers in nanomedicine due to their versatility and biocompatibility, but optimizing their effectiveness in drug delivery requires understanding their interactions with and uptake by cells. Notably, albumin interacts with the cellular glycocalyx, a phenomenon particularly studied in endothelial cells. This observation suggests that the glycocalyx could modulate ABNP uptake and therapeutic efficacy, although this possibility remains unrecognized. In this study, we elucidate the critical role of the glycocalyx in the cellular uptake of a model ABNP system consisting of silica nanoparticles (NPs) coated with native, cationic, and anionic albumin variants (BSA, BSA+, and BSA-). Using various methodologies-including fluorescence anisotropy, dynamic light scattering, microscale thermophoresis, surface plasmon resonance spectroscopy, and computer simulations─we found that both BSA and BSA+, but not BSA-, interact with heparin, a model glycosaminoglycan (GAG). To explore the influence of albumin-GAG interactions on NP uptake, we performed comparative uptake studies in wild-type and GAG-mutated Chinese hamster ovary cells (CHO), along with complementary approaches such as enzymatic GAG cleavage in wild-type cells, chemical inhibition, and competition assays with exogenous heparin. We found that the glycocalyx enhances the cell uptake of NPs coated with BSA and BSA+, while serving as a barrier to the uptake of NPs coated with BSA-. Furthermore, we showed that harnessing albumin-GAG interactions increases cancer cell death induced by paclitaxel-loaded albumin-coated NPs. These findings underscore the importance of albumin-glycocalyx interactions in the rational design and optimization of albumin-based drug delivery systems.

Emerging trends in virus and virus-like particle gene therapy delivery to the brain

Recent advances in gene therapy and gene-editing techniques offer the very real potential for successful treatment of neurological diseases. However, drug delivery constraints continue to impede viable therapeutic interventions targeting the brain due to its anatomical complexity and highly restrictive microvasculature that is impervious to many molecules. Realizing the therapeutic potential of gene-based therapies requires robust encapsulation and safe and efficient delivery to the target cells. Although viral vectors have been widely used for targeted delivery of gene-based therapies, drawbacks such as host genome integration, prolonged expression, undesired off-target mutations, and immunogenicity have led to the development of alternative strategies. Engineered virus-like particles (eVLPs) are an emerging, promising platform that can be engineered to achieve neurotropism through pseudotyping. This review outlines strategies to improve eVLP neurotropism for therapeutic brain delivery of gene-editing agents.

Revolutionizing Alzheimer's treatment: Harnessing human serum albumin for targeted drug delivery and therapy advancements

Alzheimer's disease (AD) is a neurodegenerative disorder initiated by amyloid-beta (Aβ) accumulation, leading to impaired cognitive function. Several delivery approaches have been improved for AD management. Among them, human serum albumin (HSA) is broadly employed for drug delivery and targeting the Aβ in AD owing to its biocompatibility, Aβ inhibitory effect, and nanoform, which showed blood-brain barrier (BBB) crossing ability via glycoprotein 60 (gp60) receptor and secreted protein acidic and rich in cysteine (SPARC) protein to transfer the drug molecules in the brain. Thus far, there is no previous review focusing on HSA and its drug delivery system in AD. Hence, the reviewed article aimed to critically compile the HSA therapeutic as well as drug delivery role in AD management. It also delivers information on how HSA-incorporated nanoparticles with surfaced embedded ligands such as TAT, GM1, and so on, not only improve BBB permeability but also increase neuron cell targetability in AD brain. Additionally, Aβ and tau pathology, including various metabolic markers likely BACE1 and BACE2, etc., are discussed. Besides, the molecular interaction of HSA with Aβ and its distinctive forms are critically reviewed that HSA can segregate Zn(II) and Cu(II) metal ions from Aβ owing to high affinity. Furthermore, the BBB drug delivery challenges in AD are addressed. Finally, the clinical formulation of HSA for the management of AD is critically discussed on how the HSA inhibits Aβ oligomer and fibril, while glycated HSA participates in amyloid plaque formation, i.e., β-structure sheet formation. This review report provides theoretical background on HSA-based AD drug delivery and makes suggestions for future prospect-related work.

Structural and tribological studies on the interaction of porcine gastric mucin with non- and cationic-modified β-lactoglobulins

β-lactoglobulin (BLG) is the major whey protein with negative charges at neutral pH in aqueous media. Thus, the interaction with mucins, the major polyanionic component of mucus, is very weak due to the electrostatic repulsion between them. The present study postulates that cationization of BLG molecules may reverse the interaction characteristics between BLG and mucin from repulsive to associative. To this end, cationic-modified BLGs were prepared by grafting positively charged ethylenediamine (EDA) moieties into the negatively charged carboxyl groups on the aspartic and glutamic acid residues and compared with non-modified BLG upon mixing with porcine gastric mucin (PGM). To characterize the structural and conformational features of PGM, non/cationized BLGs, and their mixtures, various spectroscopic approaches, including zeta potential, dynamic light scattering (DLS), and circular dichroism (CD) spectroscopy were employed. Importantly, we have taken surface adsorption with optical waveguide lightmode spectroscopy (OWLS), and tribological properties with pin-on-disk tribometry at the sliding interface as the key approaches to determine the interaction nature between them as mixing PGM with polycations can lead to synergistic lubrication at the nonpolar substrate in neutral aqueous media as a result of an electrostatic association. All the spectroscopic studies and a substantial improvement in lubricity collectively supported a tenacious and associative interaction between PGM and cationized BLGs, but not between PGM and non-modified BLG. This study demonstrates a unique and successful approach to intensify the interaction between BLG and mucins, which is meaningful for a broad range of disciplines, including food science, macromolecular interactions, and biolubrication etc.

Molecular dynamic investigation for Roco4 kinase inhibitor as treatment options for parkinsonism

CONTEXT

Parkinson's disease is a neurodegenerative condition characterized by the degeneration of dopaminergic neurons, resulting in motor disabilities such as rigidity, bradykinesia, postural instability, and resting tremors. While the exact cause of Parkinson's remains uncertain, both familial and sporadic forms are often associated with the G2019S mutation found in the kinase domain of LRRK2. Roco4 is an analogue of LRRK2 protein in Dictyostelium discoideum which is an established model organism to investigate LRRK2 inhibitors. In this study, the potential treatment of Parkinson's was explored by inhibiting the activity of the mutated LRRK2 protein using Roco4 as the base protein structure. Mongolicain-A and Bacoside-A exhibited significant selectivity towards the G2019S mutation, displaying a binding affinity of - 12.3 Kcal/mol and - 11.4 Kcal/mol respectively. Mongolicain-A demonstrated increased specificity towards Roco4, while Bacoside-A demonstrated significant binding affinity to all 34 kinases proteins alike. The Molecular Dynamics Studies (MDS) results strongly suggests that Mongolicain-A is a significant inhibitor of Roco4 kinase. ADMET and drugability analysis also suggests that among the two best ligands, Mongolicain-A demonstrates significant physicochemical properties to be suitable for best drug like molecule. Based on the in-silico molecular docking, molecular dynamic simulation, ADMET and drugability analyses, it is strongly suggested that, Mongolicain-A could be a potential candidate for treatment and management of Parkinson's disease via inhibition of LRRK2 protein. Further in-vitro and in-vivo investigations are in demand to validate these findings.

METHODS

To identify potential inhibitors, 3069 phytochemicals were screened using molecular docking via AutoDock Vina. Molecular Dynamics Simulation was carried out using GROMACS 2022.2 for a duration of 100ns per complex to study the stability and inhibition potential of the protein ligand complexes. ADMET analysis was carriedout using Molinspiration and preADMET web tool.

Niosomes: A Smart Drug Delivery System for Brain Targeting

Niosomes are lipid-based nanovesicles that have the potential to act as drug-delivery vehicles for a variety of agents. They are effective drug delivery systems for both ASOs and AAV vectors, with advantages such as improved stability, bioavailability, and targeted administration. In the context of brain-targeted drug delivery, niosomes have been investigated as a drug delivery system for brain targeting, but more research is needed to optimize their formulation to improve their stability and release profile and address the challenges of scale-up and commercialization. Despite these challenges, several applications of niosomes have demonstrated the potential of novel nanocarriers for targeted drug delivery to the brain. This review briefly overviews the current use of niosomes in treating brain disorders and diseases.

Novel Biomaterials Based Strategies for Neurodegeneration: Recent Advancements and Future Prospects

Neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and Huntington's disease, pose significant challenges for effective treatment due to the complex nature of the central nervous system and the limited delivery of therapeutic agents to the brain. Biomaterial-based drug delivery systems offer promising strategies to overcome these challenges and improve therapeutic outcomes. These systems utilize various biomaterials, such as nanoparticles, hydrogels, and implants, to deliver drugs, genes, or cells to the affected regions of the brain. They provide advantages such as targeted delivery, controlled release, and protection of therapeutic agents. This review examines the role of biomaterials in drug delivery for neurodegeneration, discussing different biomaterialbased approaches, including surface modification, encapsulation, and functionalization techniques. Furthermore, it explores the challenges, future perspectives, and potential impact of biomaterialbased drug delivery systems in the field of neurodegenerative diseases.

Albumin-manganese dioxide nanocomposites: a potent inhibitor and ROS scavenger against Alzheimer's β-amyloid fibrillogenesis and neuroinflammation

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease pathologically caused by amyloid-β protein (Aβ) aggregation, oxidative stress, and neuroinflammation. The pathogenesis of AD is still uncertain and intricate, and helpful therapy has rarely been recorded. So, discovering amyloid modulators is deemed a promising avenue for preventing and treating AD. In this study, human serum albumin (HSA), a protein-based Aβ inhibitor, was utilized as a template to guide the synthesis of HSA-manganese dioxide nanocomposites (HMn NCs) through biomineralization. The in situ formed MnO2 in HSA endows this nano-platform with outstanding reactive oxygen species (ROS) scavenging capability, including superoxide dismutase-mimetic and catalase-mimetic activities, which could scavenge the plethora of superoxide anion radicals and hydrogen peroxide. More importantly, the HMn NCs show enhanced potency in suppressing Aβ fibrillization compared with HSA, which further alleviates Aβ-mediated SH-SY5Y neurotoxicity by scavenging excessive ROS. Moreover, it is demonstrated that HMn NCs reduce Aβ-related inflammation in BV-2 cells by lowering tumor necrosis factor-α and interleukin-6. Furthermore, transgenic C. elegans studies showed that HMn NCs could remove Aβ plaques, reduce ROS in CL2006 worms, and promote the lifespan extension of worms. Thus, HMn NCs provide a promising tactic to facilitate the application of multifunctional nanocomposites in AD treatment.

EGFR targeted albumin nanoparticles of oleanolic acid: In silico screening of nanocarrier, cytotoxicity and pharmacokinetics for lung cancer therapy

This study aimed to develop cetuximab (CTX) functionalized albumin nanoparticles (ALB-NPs) of oleanolic acid for EGFR targeted lung cancer therapy. The molecular docking methodology has been applied for a selection of suitable nanocarrier. Various physicochemical parameters like particle size, polydispersity, zeta potential, morphology, entrapment efficiency, and in-vitro drug release of all the ALB-NPs were analyzed. Furthermore, the in-vitro qualitative and quantitative cellular uptake study revealed that higher uptake of CTX conjugated ALB-NPs than nontargeted ALB-NPs in A549 cells. The in-vitro MTT assay revealed that the IC50 value of CTX-OLA-ALB-NPs (4.34 ± 1.90 μg/mL) was significantly reduced (p < 0.001) than OLA-ALB-NPs (13.87 ± 1.28 μg/mL) in A-549 cells. CTX-OLA-ALB-NPs caused apoptosis in A-549 cells at concentrations equivalent to its IC50 value and blocked the cell cycle in the G0/G1 phases. The hemocompatibility, histopathology and lung safety study confirmed the biocompatibility of the developed NPs. In vivo ultrasound and photoacoustic imaging confirmed the targeted delivery of the NPs to lung cancer. The findings demonstrated that CTX-OLA-ALB-NPs have potential for site-specific delivery of OLA for effective and targeted therapy of lung carcinoma.

Engineering nanosystems to overcome barriers to cancer diagnosis and treatment

Over the past two decades, multidisciplinary investigations into the development of nanoparticles for medical applications have continually increased. However, nanoparticles are still subject to biological barriers and biodistribution challenges, which limit their overall clinical potential. This has motivated the implementation of innovational modifications to a range of nanoparticle formulations designed for cancer imaging and/or cancer treatment to overcome specific barriers and shift the accumulation of payloads toward the diseased tissues. In recent years, novel technological and chemical approaches have been employed to modify or functionalize the surface of nanoparticles or manipulate the characteristics of nanoparticles. Combining these approaches with the identification of critical biomarkers provides new strategies for enhancing nanoparticle specificity for both cancer diagnostic and therapeutic applications. This review discusses the most recent advances in the design and engineering of nanoparticles as well as future directions for developing the next generation of nanomedicines.

Improved biopharmaceutical performance of antipsychotic drug using lipid nanoparticles via intraperitoneal route

This study aims to develop, characterize, and examine olanzapine-loaded solid lipid nanocarriers (OLAN-SLNs) for effective brain delivery. OLAN has poor water solubility and low penetration through blood-brain barrier (BBB). Herein, OLAN-SLNs were fabricated using high-pressure homogenization (HPH) method followed by their investigation for particle properties. Moreover, in vitro release and in vivo pharmacokinetics profiles of OLAN-SLNs were compared with pure drug. Anti-psychotic activity was performed in LPS-induced psychosis mice model. Furthermore, expressions of the COX-2 and NF-κB were measured trailed by histopathological examination. The optimized formulation demonstrated nanoparticle size (149.1 nm) with rounded morphology, negative zeta potential (-28.9 mV), lower PDI (0.334), and excellent entrapment efficiency (95%). OLAN-SLNs significantly retarded the drug release and showed sustained release pattern as compared to OLAN suspension. Significantly enhanced bioavailability (ninefold) was demonstrated in OLAN-SLNs when compared with OLAN suspension. Behavioral tests showed significantly less immobility and more struggling time in OLAN-SLNs treated mice group. Additionally, reduced expression of COX-2 and -NF κB in brain was found. Altogether, it can be concluded that SLNs have the potential to deliver active pharmaceutical ingredients to brain, most importantly to enhance their bioavailability and antipsychotic effect, as indicated for OLAN in this study.

Biopolymer Nanoparticles for Nose-to-Brain Drug Delivery: A New Promising Approach for the Treatment of Neurological Diseases

Diseases affecting the central nervous system (CNS) are among the most disabling and the most difficult to cure due to the presence of the blood-brain barrier (BBB) which represents an impediment from a therapeutic and diagnostic point of view as it limits the entry of most drugs. The use of biocompatible polymer nanoparticles (NPs) as vehicles for targeted drug delivery to the brain arouses increasing interest. However, the route of administration of these vectors remains critical as the drug must be delivered without being degraded to achieve a therapeutic effect. An innovative approach for the administration of drugs to the brain using polymeric carriers is represented by the nose-to-brain (NtB) route which involves the administration of the therapeutic molecule through the neuro-olfactory epithelium of the nasal mucosa. Nasal administration is a non-invasive approach that allows the rapid transport of the drug directly to the brain and minimizes its systemic exposure. To date, many studies involve the use of polymer NPs for the NtB transport of drugs to the brain for the treatment of a whole series of disabling neurological diseases for which, as of today, there is no cure. In this review, various types of biodegradable polymer NPs for drug delivery to the brain through the NtB route are discussed and particular attention is devoted to the treatment of neurological diseases such as Glioblastoma and neurodegenerative diseases.

Aptamer-Modified Erythrocyte Membrane-Coated pH-Sensitive Nanoparticles for c-Met-Targeted Therapy of Glioblastoma Multiforme

Biomimetic drug delivery systems, especially red blood cell (RBC) membrane-based nanoparticle drug delivery systems (RNP), have been extensively utilized in tumor drug delivery because of their excellent biocompatibility and prolonged circulation. In this study, we developed an active targeting pH-sensitive RNP loaded with DOX by decorating an aptamer SL1 on RBC membranes (SL1-RNP-DOX) for c-Met-targeted therapy of glioblastoma multiforme (GBM). SL1 could specifically bind to c-Met, which is highly expressed in GBM U87MG cells and facilitate DOX delivery to GBM cells. In vitro studies demonstrated that U87MG cells had a higher uptake of SL1-RNP-DOX (3.25 folds) and a stronger pro-apoptosis effect than unmodified RNP-DOX. In vivo fluorescence imaging and tissue distribution further demonstrated the higher tumor distribution of SL1-RNP-DOX (2.17 folds) compared with RNP-DOX. As a result, SL1-RNP-DOX presented the best anti-GBM effect with a prolonged median survival time (23 days vs. 15.5 days) and the strongest tumor cell apoptosis in vivo among all groups. In conclusion, SL1-RNP-DOX exhibited a promising targeting delivery strategy for GBM therapy.

Blood-brain barrier: emerging trends on transport models and new-age strategies for therapeutics intervention against neurological disorders

The integrity of the blood–brain barrier (BBB) is essential for normal central nervous system (CNS) functioning. Considering the significance of BBB in maintaining homeostasis and the neural environment, we aim to provide an overview of significant aspects of BBB. Worldwide, the treatment of neurological diseases caused by BBB disruption has been a major challenge. BBB also restricts entry of neuro-therapeutic drugs and hinders treatment modalities. Hence, currently nanotechnology-based approaches are being explored on large scale as alternatives to conventional methodologies. It is necessary to investigate the in-depth characteristic features of BBB to facilitate the discovery of novel drugs that can successfully cross the barrier and target the disease effectively. It is imperative to discover novel strategies to treat life-threatening CNS diseases in humans. Therefore, insights regarding building blocks of BBB, activation of immune response on breach of this barrier, and various autoimmune neurological disorders caused due to BBB dysfunction are discussed. Further, special emphasis is given on delineating BBB disruption leading to CNS disorders. Moreover, various mechanisms of transport pathways across BBB, several novel strategies, and alternative routes by which drugs can be properly delivered into CNS are also discussed.

Inhibition of the CEBPβ-NFκB interaction by nanocarrier-packaged Carnosic acid ameliorates glia-mediated neuroinflammation and improves cognitive function in an Alzheimer's disease model

Neuroinflammation occurs early in Alzheimer’s disease (AD). The initial stage of AD is related to glial dysfunction, which contributes to impairment of Aβ clearance and disruption of synaptic connection. CEBPβ, a member of the CCAAT-enhancer-binding protein (CEBP) family, modulates the expression of inflammation-associated genes, and its expression is elevated in brains undergoing degeneration and injured brains. However, the mechanism underlying CEBPβ-mediated chronic inflammation in AD is unclear. In this study, we observed that increases in the levels of nuclear CEBPβ facilitated the interaction of CEBPβ with the NFκB p65 subunit, increasing the transcription of proinflammatory cytokines in the APP/PS1 mouse brain. Oral administration of nanocarrier-packaged carnosic acid (CA) reduced the aberrant activation of microglia and astrocytes and diminished mature IL-1β, TNFα and IL-6 production in the APP/PS1 mouse brain. CA administration reduced β-amyloid (Aβ) deposition and ameliorated cognitive impairment in APP/PS1 mice. We observed that CA blocked the interaction of CEBPβ with NFκB p65, and chromatin immunoprecipitation revealed that CA reduced the transcription of the NFκB target genes TNFα and IL-6. We confirmed that CA alleviated inflammatory mediator-induced neuronal degeneration and reduced Aβ secretion by inhibiting the CEBPβ-NFκB signalling pathway in vitro. Sulfobutyl ether-beta-cyclodextrin (SBEβCD) was used as the encapsulation agent for the CA-loaded nanocarrier to overcome the poor water solubility and enhance the brain bioavailability of CA. The CA nanoparticles (NPs) had no obvious toxicity. We demonstrated a feasible SBEβCD-based nanodelivery system targeting the brain. Our data provide experimental evidence that CA-loaded NPs are potential therapeutic agents for AD treatment.

Modernistic and Emerging Developments of Nanotechnology in Glioblastoma-Targeted Theranostic Applications

Brain tumors such as glioblastoma are typically associated with an unstoppable cell proliferation with aggressive infiltration behavior and a shortened life span. Though treatment options such as chemotherapy and radiotherapy are available in combating glioblastoma, satisfactory therapeutics are still not available due to the high impermeability of the blood–brain barrier. To address these concerns, recently, multifarious theranostics based on nanotechnology have been developed, which can deal with diagnosis and therapy together. The multifunctional nanomaterials find a strategic path against glioblastoma by adjoining novel thermal and magnetic therapy approaches. Their convenient combination of specific features such as real-time tracking, in-depth tissue penetration, drug-loading capacity, and contrasting performance is of great demand in the clinical investigation of glioblastoma. The potential benefits of nanomaterials including specificity, surface tunability, biodegradability, non-toxicity, ligand functionalization, and near-infrared (NIR) and photoacoustic (PA) imaging are sufficient in developing effective theranostics. This review discusses the recent developments in nanotechnology toward the diagnosis, drug delivery, and therapy regarding glioblastoma.

Study on the stability and oral bioavailability of curcumin loaded (-)-epigallocatechin-3-gallate/poly(N-vinylpyrrolidone) nanoparticles based on hydrogen bonding-driven self-assembly

The biological activity and absorption of curcumin (Cur) is limited in application due to its low water solubility, poorstabilityand rapid metabolism. In this work, Cur loaded (-)-epigallocatechin-3-gallate (EGCG)/poly(N-vinylpyrrolidone) (PVP) nanoparticles (CEP-NPs) was successfully fabricated via self-assembly driven by hydrogen bonding, providing with desirable Cur-loading efficiency, high stability, strong antioxidant capacity, and pH-triggered intestinal targeted release properties. Molecular dynamics simulations further indicated the Cur was coated with EGCG and PVP in CEP-NPs and high acid prolonged release property was attribute to low ionization degree of EGCG. Besides, the enhanced intestinal absorption of Cur was related to inhibition of Cur metabolism by EGCG, enhancement of cellular uptake and higher Caco-2 monolayer permeation. Pharmacokinetic study showed that the oral bioavailability presented nearly 12-fold increment. Therefore, this study provides a new horizon for improving the Cur utilization in food and pharmaceutical fields.

Nanocarriers Call the Last Shot in the Treatment of Brain Cancers

Our brain is protected by physio-biological barriers. The blood–brain barrier (BBB) main mechanism of protection relates to the abundance of tight junctions (TJs) and efflux pumps. Although BBB is crucial for healthy brain protection against toxins, it also leads to failure in a devastating disease like brain cancer. Recently, nanocarriers have been shown to pass through the BBB and improve patients’ survival rates, thus becoming promising treatment strategies. Among nanocarriers, inorganic nanocarriers, solid lipid nanoparticles, liposomes, polymers, micelles, and dendrimers have reached clinical trials after delivering promising results in preclinical investigations. The size of these nanocarriers is between 10 and 1000 nm and is modified by surface attachment of proteins, peptides, antibodies, or surfactants. Multiple research groups have reported transcellular entrance as the main mechanism allowing for these nanocarriers to cross BBB. Transport proteins and transcellular lipophilic pathways exist in BBB for small and lipophilic molecules. Nanocarriers cannot enter via the paracellular route, which is limited to water-soluble agents due to the TJs and their small pore size. There are currently several nanocarriers in clinical trials for the treatment of brain cancer. This article reviews challenges as well as fitting attributes of nanocarriers for brain tumor treatment in preclinical and clinical studies.

Development of Polymer-Based Nanoformulations for Glioblastoma Brain Cancer Therapy and Diagnosis: An Update

Brain cancers, mainly high-grade gliomas/glioblastoma, are characterized by uncontrolled proliferation and recurrence with an extremely poor prognosis. Despite various conventional treatment strategies, viz., resection, chemotherapy, and radiotherapy, the outcomes are still inefficient against glioblastoma. The blood–brain barrier is one of the major issues that affect the effective delivery of drugs to the brain for glioblastoma therapy. Various studies have been undergone in order to find novel therapeutic strategies for effective glioblastoma treatment. The advent of nanodiagnostics, i.e., imaging combined with therapies termed as nanotheranostics, can improve the therapeutic efficacy by determining the extent of tumour distribution prior to surgery as well as the response to a treatment regimen after surgery. Polymer nanoparticles gain tremendous attention due to their versatile nature for modification that allows precise targeting, diagnosis, and drug delivery to the brain with minimal adverse side effects. This review addresses the advancements of polymer nanoparticles in drug delivery, diagnosis, and therapy against brain cancer. The mechanisms of drug delivery to the brain of these systems and their future directions are also briefly discussed.

Biosupramolecular complexes of amphiphilic photosensitizers with human serum albumin and cucurbit[7]uril as carriers for photodynamic therapy

In the present work, we evaluated the supramolecular interactions between three photosensitizers, namely toluidine blue O (TBO, positively charged) and two fatty acid conjugates of 6 and 14 carbon atoms chain lengths (TBOC6 and TBOC14), with human serum albumin (HSA) and the macrocycle cucurbit[7]uril (CB[7]), alone or in combination within a biosupramolecular system as potential carriers of photosensitizers for Photodynamic therapy (PDT). Binding studies were carried out using photophysical and calorimetric techniques and accompanied with molecular docking simulations. Amphiphilic photosensitizers, particularly TBOC14, showed stronger binding to HSA and (CB[7]). Comparing the different delivery systems, (CB[7]) had a marginal effect on cell uptake and phototoxicity in HeLa cells, while HSA showed enhanced cell uptake with phototoxicities that depended on the photosensitizer. Despite low cell uptake, the combination of both (CB[7]) and HSA was the most phototoxic, which illustrates the potential of combining these systems for PDT applications.

New Perspectives of Gene Therapy on Polyglutamine Spinocerebellar Ataxias: From Molecular Targets to Novel Nanovectors

Seven of the most frequent spinocerebellar ataxias (SCAs) are caused by a pathological expansion of a cytosine, adenine and guanine (CAG) trinucleotide repeat located in exonic regions of unrelated genes, which in turn leads to the synthesis of polyglutamine (polyQ) proteins. PolyQ proteins are prone to aggregate and form intracellular inclusions, which alter diverse cellular pathways, including transcriptional regulation, protein clearance, calcium homeostasis and apoptosis, ultimately leading to neurodegeneration. At present, treatment for SCAs is limited to symptomatic intervention, and there is no therapeutic approach to prevent or reverse disease progression. This review provides a compilation of the experimental advances obtained in cell-based and animal models toward the development of gene therapy strategies against polyQ SCAs, providing a discussion of their potential application in clinical trials. In the second part, we describe the promising potential of nanotechnology developments to treat polyQ SCA diseases. We describe, in detail, how the design of nanoparticle (NP) systems with different physicochemical and functionalization characteristics has been approached, in order to determine their ability to evade the immune system response and to enhance brain delivery of molecular tools. In the final part of this review, the imminent application of NP-based strategies in clinical trials for the treatment of polyQ SCA diseases is discussed.

New advances in brain-targeting nano-drug delivery systems for Alzheimer's disease

Alzheimer's disease (AD) is the most common neurodegenerative disease worldwide and its incidence is increasing due to the ageing population. Currently, the main limitations of AD treatment are low blood-brain barrier permeability, severe off-target of drugs, and immune abnormality. In this review, four hypotheses for Alzheimer's pathogenesis and three challenges for Alzheimer's drug delivery are discussed. In addition, this article summarises the different strategies of brain targeting nano-drug delivery systems (NDDSs) developed in the last 10 years. These strategies include receptor-mediated (transferrin receptor, low-density lipoprotein receptor-related protein, lactoferrin receptor, etc.), adsorption-mediated (cationic, alkaline polypeptide, cell-penetrating peptides, etc.), and transporter-mediated (P-gp, GLUT1, etc.). Moreover, it provides insights into novel strategies used in AD, such as exosomes, virus-like particles, and cell membrane coating particles. Hence, this review will help researchers to understand the current progress in the field of NDDSs for the central nervous system and find new directions for AD therapy.HighlightsCharacteristics and challenges based on the pathogenesis of AD were discussed.Recent advances in novel brain-targeting NDDSs for AD over the past 10 years were summarised.

Surface charge, glycocalyx, and blood-brain barrier function

The negative surface charge of brain microvessel endothelial cells is derived from the special composition of their membrane lipids and the thick endothelial surface glycocalyx. They are important elements of the unique defense systems of the blood-brain barrier. The tissue-specific properties, components, function and charge of the brain endothelial glycocalyx have only been studied in detail in the past 15 years. This review highlights the importance of the negative surface charge in the permeability of macromolecules and nanoparticles as well as in drug interactions. We discuss surface charge and glycoxalyx changes in pathologies related to the brain microvasculature and protective measures against glycocalyx shedding and damage. We present biophysical techniques, including a microfluidic chip device, to measure surface charge of living brain endothelial cells and imaging methods for visualization of surface charge and glycocalyx.

Surface Functionalization of PLGA Nanoparticles to Increase Transport across the BBB for Alzheimer’s Disease

Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that accounts for about 60% of all diagnosed cases of dementia worldwide. Although there are currently several drugs marketed for its treatment, none are capable of slowing down or stopping the progression of AD. The role of the blood-brain barrier (BBB) plays a key role in the design of a successful treatment for this neurodegenerative disease. Nanosized particles have been proposed as suitable drug delivery systems to overcome BBB with the purpose of increasing bioavailability of drugs in the brain. Biodegradable poly (lactic-co-glycolic acid) nanoparticles (PLGA-NPs) have been particularly regarded as promising drug delivery systems as they can be surface-tailored with functionalized molecules for site-specific targeting. In this review, a thorough discussion about the most recent functionalization strategies based on PLGA-NPs for AD and their mechanisms of action is provided, together with a description of AD pathogenesis and the role of the BBB in brain targeting.

Natural biomaterials in brain repair: A focus on collagen

Biomaterials derived from natural resources have increasingly been used for versatile applications in the central nervous system (CNS). Thanks to their biocompatibility and biodegradability, natural biomaterials offer vast possibilities for future clinical repair strategies for the CNS. These materials can be used for diverse applications such as hydrogels to fill the tissue cavities, microparticles to deliver drugs across the blood-brain barrier, and scaffolds to transplant stem cells. In this review, various uses of prominent protein and polysaccharide biomaterials, with a special focus on collagen, in repair and regenerative applications for the brain are summarized together with their individual advantages and disadvantages.

When Albumin Meets Liposomes: A Feasible Drug Carrier for Biomedical Applications

Albumin, the most abundant protein in plasma, possesses some inherent beneficial structural and physiological characteristics that make it suitable for use as a drug delivery agent, such as an extraordinary drug-binding capacity and long blood retention, with a high biocompatibility. The use of these characteristics as a nanoparticle drug delivery system (DDS) offers several advantages, including a longer circulation time, lower toxicity, and more significant drug loading. To date, many innovative liposome preparations have been developed in which albumin is involved as a DDS. These novel albumin-containing liposome preparations show superior deliverability for genes, hydrophilic/hydrophobic substances and proteins/peptides to the targeting area compared to original liposomes by virtue of their high biocompatibility, stability, effective loading content, and the capacity for targeting. This review summarizes the current status of albumin applications in liposome-based DDS, focusing on albumin-coated liposomes and albumin-encapsulated liposomes as a DDS carrier for potential medical applications.

Use of Super Paramagnetic Iron Oxide Nanoparticles as Drug Carriers in Brain and Ear: State of the Art and Challenges

Drug delivery and distribution in the central nervous system (CNS) and the inner ear represent a challenge for the medical and scientific world, especially because of the blood-brain and the blood-perilymph barriers. Solutions are being studied to circumvent or to facilitate drug diffusion across these structures. Using superparamagnetic iron oxide nanoparticles (SPIONs), which can be coated to change their properties and ensure biocompatibility, represents a promising tool as a drug carrier. They can act as nanocarriers and can be driven with precision by magnetic forces. The aim of this study was to systematically review the use of SPIONs in the CNS and the inner ear. A systematic PubMed search between 1999 and 2019 yielded 97 studies. In this review, we describe the applications of the SPIONS, their design, their administration, their pharmacokinetic, their toxicity and the methods used for targeted delivery of drugs into the ear and the CNS.

Nanoparticles Dual Targeting Both Myeloma Cells and Cancer-Associated Fibroblasts Simultaneously to Improve Multiple Myeloma Treatment

Cancer-associated fibroblasts (CAFs) and myeloma cells could mutually drive myeloma progression, indicating that drug delivery to kill both CAFs and myeloma cells simultaneously could achieve better therapeutic benefits than to kill each cell type alone. Here, we designed a dual-targeting drug delivery system by conjugating paclitaxel (PTX)-loaded poly(ethylene glycol)-poly(lactic acid) nanoparticles (NPs) with a cyclic peptide (CNPs-PTX) with a special affinity with platelet-derived growth factor/platelet-derived growth factor receptor (PDGFR-β) overexpressed on both CAFs and myeloma cells. Cellular uptake experiments revealed that the cyclic peptide modification on CNPs could significantly enhance CNPs uptake by both CAFs and myeloma cells compared with unmodified NPs. Cytotoxicity tests showed that CNPs-PTX was more toxic to both CAFs and myeloma cells compared with its counterpart PTX-loaded conventional NPs (NPs-PTX). In vivo imaging and biodistribution experiments showed that CNPs could abundantly accumulate in tumors and were highly co-localized with CAFs and myeloma cells. The in vivo anti-tumor experiments confirmed that the anti-myeloma efficacy of CNPs-PTX was significantly stronger than that of NPs-PTX and free drugs. In summary, it is the first time that a dual-targeting strategy was utilized in the field of myeloma treatment through targeting both CAFs and myeloma cells simultaneously, which harbors a high potential of clinical translation for myeloma treatment.

Central nervous system delivery of molecules across the blood-brain barrier

Therapies targeting neurological conditions such as Alzheimer's or Parkinson's diseases are hampered by the presence of the blood-brain barrier (BBB). During the last decades, several approaches have been developed to overcome the BBB, such as the use of nanoparticles (NPs) based on biomaterials, or alternative methods to open the BBB. In this review, we briefly highlight these strategies and the most recent advances in this field. Limitations and advantages of each approach are discussed. Combination of several methods such as functionalized NPs targeting the receptor-mediated transcytosis system with the use of magnetic resonance imaging-guided focused ultrasound (FUS) might be a promising strategy to develop theranostic tools as well as to safely deliver therapeutic molecules, such as drugs, neurotrophic factors or antibodies within the brain parenchyma.

Modulation of immune responses with nanoparticles and reduction of their immunotoxicity

Particles with a size range of 1-100 nm used in various fields of life sciences are called nanoparticles (NPs). Currently, nanotechnology has a wide range of applications in biomedical research, industries and in almost all types of modern technology. The growing applications of nanotechnology in medicine urge scientists to analyze the impact of NPs on human body tissues and the immune system. Easy surface modifications of the NPs enable the modulation of the immune system either by evading the immune system to prevent allergic reactions or by enhancing the immunogenic response. In this review, we discussed the various possible theories and practical implications reported to date for the applications of nanotechnology in immunostimulation and immunosuppression for favorable immune response, such as vaccine delivery and cancer treatments. In the last part of this paper, we also discussed the biocompatibility and unfavorable immunotoxicity of NPs and methods for lowering their toxicity.

Overcoming the Blood-Brain Barrier: Functionalised Chitosan Nanocarriers

The major impediment to the delivery of therapeutics to the brain is the presence of the blood-brain barrier (BBB). The BBB allows for the entrance of essential nutrients while excluding harmful substances, including most therapeutic agents; hence, brain disorders, especially tumours, are very difficult to treat. Chitosan is a well-researched polymer that offers advantageous biological and chemical properties, such as mucoadhesion and the ease of functionalisation. Chitosan-based nanocarriers (CsNCs) establish ionic interactions with the endothelial cells, facilitating the crossing of drugs through the BBB by adsorptive mediated transcytosis. This process is further enhanced by modifications of the structure of chitosan, owing to the presence of reactive amino and hydroxyl groups. Finally, by permanently binding ligands or molecules, such as antibodies or lipids, CsNCs have showed a boosted passage through the BBB, in both in vivo and in vitro studies which will be discussed in this review.

Does Pharmacodynamics of Drugs Change After Presenting them as Nanoparticles Like their Pharmacokinetics?

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Nowadays, the breakthrough in different medical branches makes it feasible to designate new methods of drug delivery to achieve the most cost-effective and the least unpleasant consequenceimposing solutions to overcome a wide range of diseases.

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Nanoparticle (NP) drugs entered the therapeutic system, especially in cancer chemotherapy. These drugs are quite well-known for two traits of being long-acting and less toxic. For a long time, it has been investigated how NPs will change the kinetics of drugs. However, there are a few studies that inclined their attention to how NPs affect the dynamics of drugs. In this review, the latter point will mainly be discussed in an example-based manner. Besides, other particular features of NPs will be briefly noted.

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NPs are capable of affecting the biologic system as much as a drug. Moreover, NPs could arise a wide variety of effects by triggering their own receptors. NPs are able to change a receptor function and manipulate its downstream signaling cascade.

PEGylated nanocarriers: A promising tool for targeted delivery to the brain

Targeted drug delivery across the blood-brain barrier is an extremely challenging quest in the fight with fatal brain ailments, with the major hurdles being short circulation time, reticuloendothelial system (RES) uptake, and excretion of nanocarriers. PEGylation has emerged as a boon for targeted drug delivery to the brain. It is well established that PEGylation can increase the circulation time of nanocarriers by avoiding RES uptake, which is indispensable for increasing the brain's uptake of nanocarriers. PEGylation also acts as a linker for ligand molecules to achieve active targeting to the brain. Using PEGylation, novel approaches are being investigated to facilitate ligand-receptor interactions at the brain endothelium to ease the entry of therapeutic drugs into the brain. In addition, PEGylation made it simpler to assess the brain tissue for delivering diagnostic molecules and theranostic nanocarriers. The potential of PEGylated nanocarriers is being investigated vastly to boost the therapeutic effect several fold in the treatment of brain diseases. This review sheds light on the contribution of PEGylated nanocarriers, especially liposomes, polymeric nanoparticles, and dendrimers for brain-specific delivery of bioactives.

Hierarchical assembly of hyaluronan coated albumin nanoparticles for pancreatic cancer chemoimmunotherapy

Pancreatic cancer is a highly malignant carcinoma with limited effective treatment options, resulting in a poor patient survival rate of less than 5%. In this study, cationic albumin nanoparticles were assembled with negatively charged hyaluronic acid (HA) to achieve a hierarchical nanostructure and efficient delivery of small molecule drugs to the tumor site in the pancreas. A combination of chemotherapy with indoleamine-2,3-dioxygenase (IDO) inhibition was explored to enhance the chemotherapeutic efficacy in vivo. Hydrophobic celastrol (CLT) and hydrophilic 1-methyltryptophan (MT) were concurrently loaded in HA coated cationic albumin nanoparticles (HNPs) with an average size of ∼300 nm. The size of HNPs was reduced in the presence of hyaluronidase to facilitate penetration into deep tumor tissues. Also, the biodistribution study in the C57BL/6 mice xenograft model showed enhanced tumor accumulation and prolonged circulation of HNPs. Compared with CLT solution, the combination of CLT with MT showed significantly enhanced tumor inhibition in both xenograft and orthotopic pancreatic cancer mice models via downregulating the immunosuppressive tumor microenvironment. Taken together, the combination of CLT with MT administered via HNPs represents a highly promising strategy for targeted pancreatic cancer therapy.

Dendrimer grafted albumin nanoparticles for the treatment of post cerebral stroke damages: A proof of concept study

Stroke is the second largest disease of mortality. The biggest hurdle in designing effective brain drug delivery systems is offered by the blood-brain barrier (BBB), which is highly impermeable to many drugs. Albumin nanoparticles (NP) have gained attention due to their multiple ligand binding sites and long circulatory half-life. Citicoline (CIT) is reported to enhance the acetylcholine secretion in the brain and also helps in membrane repair and regeneration. However, the poor BBB permeation of CIT results in lower levels of CIT in the brain. This demands the development of a suitable delivery platform to completely realize the therapeutic benefit of CIT in stroke therapy. This investigation reports the synthesis and characterization of second generation (2.0 G) dendrimer Amplified Albumin (dAA) biopolymer by FTIR, MALDI-TOF, and surface charge (mV). Further, the synthesized biopolymer has been utilized to develop a CIT nanoformulation using a commercially translatable one-pot process. Release of CIT from biopolymer was performed within an acetate buffer at pH 5 and Phosphate buffer at pH 7.4. Further, we investigated the ability of biopolymer to permeate BBB by in vitro permeability assay in bEnd.3 cells. MTT assay of CIT-dAA-NP, CIT-ANP, and 2.0 G PAMAM dendrimers was performed in bEnd.3 cells. Therapeutic efficacy of the synthesized biopolymer was determined by VEGF gene expression within an in vitro hypoxia model in PC12 cells. Thus, this investigation resulted in biopolymers that can be used to deliver any therapeutic agent by altering the permeability of the BBB. Also, cationization by dendrimer grafting is one such strategy that may be used to cationize any other negatively charged polymer, such as albumin. The synthesized biopolymer is not limited to deliver molecules to the brain, but can also be used to increase the loading of negatively-charged drug molecules, siRNA, or any other oligonucleotide.

Synthesis and characterisation of iron oxide nanoparticles conjugated with epidermal growth factor receptor (EGFR) monoclonal antibody as MRI contrast agent for cancer detection

The aim of this study is to synthesise superparamagnetic iron oxide nanoparticles conjugated with anti-epidermal growth factor receptor monoclonal antibody (ANTI-EGFR-SPION) and investigate its physicochemical characterisation and biocompatibility as a targeted magnetic resonance imaging (MRI) contrast agent for the EGFR-specific detection in EGFR expressing tumour cells. These particles employed biocompatible polymers, poly(D,L-lactide-co-glycolide) (PLGA) and polyethylene glycol aldehyde (PEG-aldehyde), to increase the half-life of particles in circulation and reduce their side effects. The Fe₃O₄-loaded PLGA-PEG-aldehyde nanoparticles were prepared by a modified water-in-oil-in-water double emulsion method. The EGFR antibody was conjugated to the surface of SPIONs using the aldehyde-amine reaction. Synthesised conjugates (nanoprobes) were characterised using Fourier transform infrared spectrophotometry, dynamic light scattering, transmission electron microscopy images, and vibrating-sample magnetometery, and the results showed that the conjugation was successful. The mean diameter of nanoprobes was about 25 nm. These nanoprobes exhibited excellent water-solubility, stability, and biocompatibility. Meanwhile, MR susceptibility test proved that synthesised nanoprobes can be managed for negative contrast enhancement. The results of this study suggested the potential use of these nanoprobes for non-invasive molecular MRI in EGFR detection in the future.

Targeting Delivery of Oligodeoxynucleotides to Macrophages by Mannosylated Cationic Albumin for Immune Stimulation in Cancer Treatment

To efficiently deliver CpG oligodeoxynucleotides (ODNs) to macrophages for the reversal of cancer-induced immunosuppression, nanoparticles ODN@MCBSA with mannosylated cationic albumin (MCBSA) as a macrophage targeting vector were constructed. Compared with ODN@CBSA with cationic albumin (CBSA) as a vector, ODN@MCBSA exhibited significantly improved cellular uptake mediated by mannose moieties, resulting in significantly enhanced secretion of proflammatory cytokines including IL-12, IL-6, TNF-α, and iNOS. The modulation of macrophages toward the favorable M1 phenotype was confirmed by the upregulated CD80 expression after being treated by ODN delivery systems. In addition to immune cells, the effects of the ODN delivery system on cancerous HeLa cells were also investigated. The results showed that ODN@MCBSA did not affect the overall tumor cell viability. However, enhanced NF-κB, p-Akt, PIK3R3, Fas, and FasL, as well as upregulated caspases were observed in tumor cells, implying the pleiotropic effects on tumor cells. Our study provides a more in-depth understanding on the immunotherapeutic effects of CpG ODNs and highlights the importance of macrophage targeting delivery to minimize the effects on tumor cells. These results indicate that MCBSA could serve as a promising delivery vector of CpG ODNs to macrophages for cancer immunotherapy.

Emerging blood–brain-barrier-crossing nanotechnology for brain cancer theranostics

The advancements, perspectives, and challenges in blood–brain-barrier (BBB)-crossing nanotechnology for effective brain tumor delivery and highly efficient brain cancer theranostics.

Transferrin receptors-targeting nanocarriers for efficient targeted delivery and transcytosis of drugs into the brain tumors: a review of recent advancements and emerging trends

Treatment of glioblastoma multiforme (GBM) is a predominant challenge in chemotherapy due to the existence of blood-brain barrier (BBB) which restricts delivery of chemotherapeutic agents to the brain together with the problem of drug penetration through hard parenchyma of the GBM. With the structural and mechanistic elucidation of the BBB under both physiological and pathological conditions, it is now viable to target central nervous system (CNS) disorders utilizing the presence of transferrin (Tf) receptors (TfRs). However, overexpression of these TfRs on the GBM cell surface can also help to avoid restrictions of GBM cells to deliver chemotherapeutic agents within the tumor. Therefore, targeting of TfR-mediated delivery could counteract drug delivery issues in GBM and create a delivery system that could cross the BBB effectively to utilize ligand-conjugated drug complexes through receptor-mediated transcytosis. Hence, approach towards successful delivery of antitumor agents to the gliomas has been making possible through targeting these overexpressed TfRs within the CNS and glioma cells. This review article presents a thorough analysis of current understanding on Tf-conjugated nanocarriers as efficient drug delivery system.

Liposome delivery systems for the treatment of Alzheimer's disease

Alzheimer's disease (AD) will affect around 115 million people worldwide by the year 2050. It is associated with the accumulation of misfolded and aggregated proteins (β-amyloid and tau) in the senile plaques and neurofibrillary tangles found in the brain. Currently available drugs for AD only temporarily alleviate symptoms and do not slow the inevitable progression of this disease. New drugs are required that act on key pathologies in order to arrest or reverse cognitive decline. However, there has been a spectacular failure rate in clinical trials of conventional small molecule drugs or biological agents. Targeted nanoliposomes represent a viable and promising drug delivery system for AD that have not yet reached clinical trials. They are biocompatible, highly flexible, and have the potential to carry many different types of therapeutic molecules across the blood-brain barrier (BBB) and into brain cells. They can be tailored to extend blood circulation time and can be directed against individual or multiple pathological targets. Modifications so far have included the use of brain-penetrating peptides, together with Aβ-targeting ligands, such as phosphatidic acid, curcumin, and a retro-inverted peptide that inhibits Aβ aggregation. Combining several modifications together into multifunctional liposomes is currently a research area of great interest. This review focuses on recent liposomal approaches to AD therapy, including mechanisms involved in facilitating their passage across the BBB, and the evaluation of new therapeutic agents for blocking Aβ and/or tau aggregation.

Specific cancer stem cell-therapy by albumin nanoparticles functionalized with CD44-mediated targeting

BACKGROUND

Cancer stem cells (CSCs) are highly proliferative and tumorigenic, which contributes to chemotherapy resistance and tumor occurrence. CSCs specific therapy may achieve excellent therapeutic effects, especially to the drug-resistant tumors.

RESULTS

In this study, we developed a kind of targeting nanoparticle system based on cationic albumin functionalized with hyaluronic acid (HA) to target the CD44 overexpressed CSCs. All-trans-retinoic acid (ATRA) was encapsulated in the nanoparticles with ultrahigh encapsulation efficiency (EE%) of 93% and loading content of 8.37%. TEM analysis showed the nanoparticles were spherical, uniform-sized and surrounded by a coating layer consists of HA. Four weeks of continuously measurements of size, PDI and EE% revealed the high stability of nanoparticles. Thanks to HA conjugation on the surface, the resultant nanoparticles (HA-eNPs) demonstrated high affinity and specific binding to CD44-enriched B16F10 cells. In vivo imaging revealed that HA-eNPs can targeted accumulate in tumor-bearing lung of mouse. The cytotoxicity tests illustrated that ATRA-laden HA-eNPs possessed better killing ability to B16F10 cells than free drug or normal nanoparticles in the same dose, indicating its good targeting property. Moreover, HA-eNPs/ATRA treatment decreased side population of B16F10 cells significantly in vitro. Finally, tumor growth was significantly inhibited by HA-eNPs/ATRA in lung metastasis tumor mice.

CONCLUSIONS

These results demonstrate that the HA functionalized albumin nanoparticles is an efficient system for targeted delivery of antitumor drugs to eliminate the CSCs.

Albumin conjugates and assemblies as versatile bio-functional additives and carriers for biomedical applications

As the most abundant plasma protein, serum albumin has been extensively studied and employed for therapeutic applications. Despite its direct clinical use for the maintenance of blood homeostasis in various medical conditions, this review exclusively summarizes and discusses albumin-based bio-conjugates and assemblies as versatile bio-functional additives and carriers in biomedical applications. As one of the smallest-sized proteins in the human body, albumin is physiochemically stable and biochemically inert. Moreover, albumin is also endowed with abundant specific binding sites for numerous therapeutic compounds, which also endow it with superior bioactivities. Firstly, due to its small size and binding specificity, albumin alone or its derived assemblies can be utilized as competent drug carriers, which can deliver drugs through the enhanced permeability and retention (EPR) effect or actively target lesion sites through binding with gp60 and secreted protein acidic and rich in cysteine (SPARC) in tumor sites. Furthermore, its biochemical stability and inertness make it a safe and biocompatible coating material for use in biomedical applications. Albumin-based surface modifying additives can be used to functionalize both macro substrates (e.g. surfaces of medical devices or implants) and nanoparticle surfaces (e.g. drug carriers and imaging contrast agents). In this review, we elaborate on the synthesis and applications of albumin-based bio-functional coatings and drug carriers, respectively.

Fabrication of peptide-linked albumin nanoconstructs for receptor-mediated delivery of asiatic acid to the brain as a preventive measure in cognitive impairment: optimization, in-vitro and in-vivo evaluation

The aim of the study was to evaluate the neuroprotective activity of glutathione (GU)-conjugated asiatic acid (AA) loaded albumin nanoparticles and establishing the drug targeting efficiency (DTE) of GU as a selective ligand for brain-targeted delivery. Albumin nanoparticles were prepared by desolvation technique and optimized using quality by design (QbD) approach. GU was conjugated with nanoparticles by carbodiimide reaction and characterized by its size and zeta potential using dynamic light scattering phenomenon. Dialysis bag technique was employed for in-vitro release study and in-vivo brain targeting efficiency was evaluated in Sprague-Dawley rats (75 mg/kg, i.p.). Neuroprotective activity was evaluated against scopolamine-induced dementia in rats. Resultant brain bioavailability of nanoparticles with 100.2 nm size and 71.59% entrapment efficiency (EE), was found 7-fold higher than AA dispersion with 293% DTE for the brain. Conjugated nanoparticles showed significantly high percentage correct alternation (p < .05), low escape latency time (p < .01), cholinesterase inhibition (p < .01) and ameliorated GU levels (p < .01) as compared to diseased animals. GU showed potential to enhance the brain delivery of AA with ameliorated neuroprotective activity due to enhanced bioavailability. This concept can serve as a platform technology for similar potential neurotherapeutics, whose clinical efficacy is still challenging owing to poor bioavailability.

'Dendrimer-Cationized-Albumin' encrusted polymeric nanoparticle improves BBB penetration and anticancer activity of doxorubicin

Glioblastoma is one of the most rapaciously growing cancer within the brain with an average lifespan of 12-15 months (5-year survival <3-4%). Doxorubicin (DOX) is clinically utilized as a first line drug in the treatment of Glioblastoma, however, its restricted entry into the brain via the blood-brain barrier (BBB), limited blood-tumor barrier (BTB) permeability, hemotoxicity, short mean half-life of 1-3 hr as well as rapid body clearance results in tremendously diminished bioactivity in glioblastoma. Dendrimer-Cationized-Albumin (dCatAlb) was synthesized following the carboxyl activation technique and the synthesized biopolymer was characterized by FTIR, MALDI-TOF and zeta potential. The prepared dCatAlb was encrusted on DOX-loaded PLGA nanoparticle core to develop a novel hybrid DOX nanoformulation (dCatAlb-pDNP; particle size: 156 ± 10.85 nm; ƺ: -10.0 ± 2.1 mV surface charge). The formulated dCatAlb-pDNP showed a unique pH-dependent DOX release profile, diminished hemolytic toxicity, higher drug uptake (<0.001) and cytotoxicity in U87MG glioblastoma cells, increase levels of caspase-3 gene in U87MG cells (approximately 5.35-fold higher) inferred that anticancer activity is primarily taking place through caspase-mediated apoptosis mechanism. The developed novel DOX nanoformulation also showed superior trans-epithelial permeation transport across monolayer bEnd.3 cells as well as notable biocompatibility and stability. The dCatAlb-pDNP showed enhanced BBB permeation efficacy as confirmed permeation assay in bEnd.3 cell-based model. The long-term formulation stability of developed nanoformulations was studied by storing them at 5 ± 2 °C and 30 ± 2 °C/60 ± 5% Relative Humidity (% RH) in the stability chamber for a period of 60 days (ICHQ1A (R2)). The outcomes of this investigation evidently indicate that dCatAlb-pDNP offers superior anticancer activity of DOX in glioblastoma cells while significantly improving its BBB permeation. The developed formulation is a biocompatible, safer and commercially viable approach to delivering DOX selectively in sustained manner glioblastoma while countering its hemolytic toxic effect, which is a major ongoing issue with conventional DOX injectable available in the market today.