Solid lipid nanoparticles for potential doxorubicin delivery in glioblastoma treatment: preliminary in vitro studies

Antibody Conjugated Nano-Enabled Drug Delivery Systems Against Brain Tumors

The use of antibody-conjugated nanoparticles for brain tumor treatment has gained significant attention in recent years. Nanoparticles functionalized with anti-transferrin receptor antibodies have shown promising results in facilitating nanoparticle uptake by endothelial cells of brain capillaries and post-capillary venules. This approach offers a potential alternative to the direct conjugation of biologics to antibodies. Furthermore, studies have demonstrated the potential of antibody-conjugated nanoparticles in targeting brain tumors, as evidenced by the specific binding of these nanoparticles to brain cancer cells. Additionally, the development of targeted nanoparticles designed to transcytoses the blood-brain barrier (BBB) to deliver small molecule drugs and therapeutic antibodies to brain metastases holds promise for brain tumor treatment. While the use of nanoparticles as a delivery method for brain cancer treatment has faced challenges, including the successful delivery of nanoparticles to malignant brain tumors due to the presence of the BBB and infiltrating cancer cells in the normal brain, recent advancements in nanoparticle-mediated drug delivery systems have shown potential for enhancing the efficacy of brain cancer therapy. Moreover, the development of brain-penetrating nanoparticles capable of distributing over clinically relevant volumes when administered via convection-enhanced delivery presents a promising strategy for improving drug delivery to brain tumors. In conclusion, the use of antibody-conjugated nanoparticles for brain tumor treatment shows great promise in overcoming the challenges associated with drug delivery to the brain. By leveraging the specific targeting capabilities of these nanoparticles, researchers are making significant strides in developing effective and targeted therapies for brain tumors.

Cell Membrane Fragment-Wrapped Parenteral Nanoemulsions: A New Drug Delivery Tool to Target Gliomas

Poor prognosis in high-grade gliomas is mainly due to fatal relapse after surgical resection in the absence of efficient chemotherapy, which is severely hampered by the blood-brain barrier. However, the leaky blood-brain-tumour barrier forms upon tumour growth and vascularization, allowing targeted nanocarrier-mediated drug delivery. The homotypic targeting ability of cell-membrane fragments obtained from cancer cells means that these fragments can be exploited to this aim. In this experimental work, injectable nanoemulsions, which have a long history of safe clinic usage, have been wrapped in glioma-cell membrane fragments via co-extrusion to give targeted, homogeneously sized, sterile formulations. These systems were then loaded with three different chemotherapeutics, in the form of hydrophobic ion pairs that can be released into the target site thanks to interactions with physiological components. The numerous assays performed in two-dimensional (2D) and three-dimensional (3D) cell models demonstrate that the proposed approach is a versatile drug-delivery platform with chemo-tactic properties towards glioma cells, with adhesive interactions between the target cell and the cell membrane fragments most likely being responsible for the effect. This approach's promising translational perspectives towards personalized nanomedicine mean that further in vivo studies are foreseen for the future.

A comprehensive review on lipid nanocarrier systems for cancer treatment: fabrication, future prospects and clinical trials

Over the last few decades, cancer has been considered a clinical challenge, being among the leading causes of mortality all over the world. Although many treatment approaches have been developed for cancer, chemotherapy is still the most utilized in the clinical setting. However, the available chemotherapeutics-based treatments have several caveats including their lack of specificity, adverse effects as well as cancer relapse and metastasis which mainly explains the low survival rate of patients. Lipid nanoparticles (LNPs) have been utilized as promising nanocarrier systems for chemotherapeutics to overcome the challenges of the currently applied therapeutic strategies for cancer treatment. Loading chemotherapeutic agent(s) into LNPs improves drug delivery at different aspects including specific targeting of tumours, and enhancing the bioavailability of drugs at the tumour site through selective release of their payload, thus reducing their undesired side effects on healthy cells. This review article delineates an overview of the clinical challenges in many cancer treatments as well as depicts the role of LNPs in achieving optimal therapeutic outcomes. Moreover, the review contains a comprehensive description of the many LNPs categories used as nanocarriers in cancer treatment to date, as well as the potential of LNPs for future applications in other areas of medicine and research.

Lipid-Based Nanocarriers in the Treatment of Glioblastoma Multiforme (GBM): Challenges and Opportunities

Glioblastoma multiforme (also known as glioblastoma; GBM) is one of the most malignant types of brain tumors that occurs in the CNS. Treatment strategies for glioblastoma are majorly comprised of surgical resection, radiotherapy, and chemotherapy along with combination therapy. Treatment of GBM is itself a tedious task but the involved barriers in GBM are one of the main impediments to move one step closer to the treatment of GBM. Basically, two of the barriers are of utmost importance in this regard, namely blood brain barrier (BBB) and blood brain tumor barrier (BBTB). This review will address different challenges and barriers in the treatment of GBM along with their etiology. The role and recent progress of lipid-based nanocarriers like liposomes, solid lipid nanocarriers (SLNs), nanostructured lipid carriers (NLCs), lipoplexes, and lipid hybrid carriers in the effective management of GBM will be discussed in detail.

Labeling Assembly of Hydrophilic Methionine into Nanoparticle for Mild-Heat Mediated Immunometabolic Therapy

Methionine metabolism has a significant impact on T cells' survival and activation even in comparison to arginine, a well-documented amino acid in metabolic therapy. However, hydrophilic methionine is hardly delivered into TME due to difficult loading and rapid diffusion. Herein, the labeling assembly of methionine into nanoparticle is developed to overcome high hydrophilicity for mild-heat mediated immunometabolic therapy. The strategy is to first label methionine with protocatechualdehyde (as the tag) via reversible Schiff-base bond, and then drive nanoassembly of methionine (MPC@Fe) mediated by iron ions. In this fashion, a loading efficiency of 40% and assembly induced photothermal characteristics can be achieved. MPC@Fe can accumulate persistently in tumor up to 36 h due to tumor-selective aggregation in acidic TME. A mild heat of 43 °C on tumor by light irradiation stimulated the immunogenic cell death and effectively generated CD8⁺ T cells. Notably, MPC@Fe assisted by mild heat promoted 4.2-fold of tumor-infiltrating INF-γ⁺ CD8⁺ T cells, leading to an inhibition ratio of 27.3-fold versus the free methionine. Such labeling assembly provides a promising methionine delivery platform to realize mild heat mediated immunometabolic therapy, and is potentially extensible to other amino acids.

Naked and Decorated Nanoparticles Containing H2S-Releasing Doxorubicin: Preparation, Characterization and Assessment of Their Antitumoral Efficiency on Various Resistant Tumor Cells

Several semisynthetic, low-cardiotoxicity doxorubicin (DOXO) conjugated have been extensively described, considering the risk of cytotoxicity loss against resistant tumor cells, which mainly present drug efflux capacity. Doxorubicin 14-[4-(4-phenyl-5-thioxo-5H-[1,2]dithiol-3-yl)]-benzoate (H₂S-DOXO) was synthetized and tested for its ability to overcome drug resistance with good intracellular accumulation. In this paper, we present a formulation study aimed to develop naked and decorated H₂S-DOXO-loaded lipid nanoparticles (NPs). NPs prepared by the "cold dilution of microemulsion" method were decorated with hyaluronic acid (HA) to obtain active targeting and characterized for their physicochemical properties, drug entrapment efficiency, long-term stability, and in vitro drug release. Best formulations were tested in vitro on human-sensitive (MCF7) and human/mouse DOXO-resistant (MDA-MDB -231 and JC) breast cancer cells, on human (U-2OS) osteosarcoma cells and DOXO-resistant human/mouse osteosarcoma cells (U-2OS/DX580/K7M2). HA-decoration by HA-cetyltrimethyl ammonium bromide electrostatic interaction on NPs surface was confirmed by Zeta potential and elemental analysis at TEM. NPs had mean diameters lower than 300 nm, 70% H₂S-DOXO entrapment efficiency, and were stable for almost 28 days. HA-decorated NPs accumulated H₂S-DOXO in Pgp-expressing cells reducing cell viability. HA-decorated NPs result in the best formulation to increase the inter-cellular H₂S-DOXO delivery and kill resistant cells, and therefore, as a future perspective, they will be taken into account for further in vivo experiments on tumor animal model.

Nanogels as Novel Nanocarrier Systems for Efficient Delivery of CNS Therapeutics

Nanogels have come out as a great potential drug delivery platform due to its prominently high colloidal stability, high drug loading, core-shell structure, good permeation property and can be responsive to environmental stimuli. Such nanoscopic drug carriers have more excellent abilities over conventional nanomaterials for permeating to brain parenchyma in vitro and in vivo. Nanogel-based system can be nanoengineered to bypass physiological barriers via non-invasive treatment, rendering it a most suitable platform for the management of neurological conditions such as neurodegenerative disorders, brain tumors, epilepsy and ischemic stroke, etc. Therapeutics of central nervous system (CNS) diseases have shown marked limited site-specific delivery of CNS by the poor access of various drugs into the brain, due to the presences of the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB). Hence, the availability of therapeutics delivery strategies is considered as one of the most major challenges facing the treatment of CNS diseases. The primary objective of this review is to elaborate the newer advances of nanogel for CNS drugs delivery, discuss the early preclinical success in the field of nanogel technology and highlight different insights on its potential neurotoxicity.

Synthesis and evaluation of sulfosuccinate-based surfactants as counterions for hydrophobic ion pairing

Hydrophobic ion pairing is a promising strategy to raise the lipophilic character of therapeutic peptides and proteins. In past studies, docusate, an all-purpose surfactant with a dialkyl sulfosuccinate structure, showed highest potential as hydrophobic counterion. Being originally not purposed for hydrophobic ion pairing, it is likely still far away from the perfect counterion. Thus, within this study, docusate analogues with various linear and branched alkyl residues were synthesized to derive systematic insights into which hydrophobic tail is most advantageous for hydrophobic ion pairing, as well as to identify lead counterions that form complexes with superior hydrophobicity. The successful synthesis of the target compounds was confirmed by FT-IR, ¹H-NMR, and ¹³C-NMR. In a screening with the model protein hemoglobin, monostearyl sulfosuccinate, dioleyl sulfosuccinate, and bis(isotridecyl) sulfosuccinate were identified as lead counterions. Their potential was further evaluated with the peptides and proteins vancomycin, insulin, and horseradish peroxidase. Dioleyl sulfosuccinate and bis(isotridecyl) sulfosuccinate significantly increased the hydrophobicity of the tested peptides and proteins determined as logP or lipophilicity determined as solubility in 1-octanol, respectively, in comparison to the gold standard docusate. Dioleyl sulfosuccinate provided an up to 8.3-fold higher partition coefficient and up to 26.5-fold higher solubility in 1-octanol than docusate, whereas bis(isotridecyl) sulfosuccinate resulted in an up to 6.7-fold improvement in the partition coefficient and up to 44.0-fold higher solubility in 1-octanol. The conjugation of highly lipophilic alkyl tails to the polar sulfosuccinate head group allows the design of promising counterions for hydrophobic ion pairing. STATEMENT OF SIGNIFICANCE: Hydrophobic ion pairing enables efficient incorporation of hydrophilic molecules into lipid-based formulations by forming complexes with hydrophobic counterions. Docusate, a sulfosuccinate with two branched alkyl tails, has shown highest potential as anionic hydrophobic counterion. As it was originally not purposed for hydrophobic ion pairing, its structure is likely still far away from the perfect counterion. To improve its properties, analogues of docusate with various alkyl tails were synthesized in the present study. The investigation of different alkyl residues allowed to derive systematic insights into which tail structures are most favorable for hydrophobic ion pairing. Moreover, the lead counterions dioleyl sulfosuccinate and bis(isotridecyl) sulfosuccinate bearing highly lipophilic alkyl tails provided a significant improvement in the hydrophobicity of the resulting complexes.

Cell penetrating peptide decorated magnetic porous silicon nanorods for glioblastoma therapy and imaging

Glioblastoma multiforme (GBM) is the most malignant primary brain tumor of the central nervous system. Despite advances in therapy, it remains largely untreatable, in part due to the low permeability of chemotherapeutic drugs across the blood-brain barrier (BBB) which significantly compromises their effectiveness. To circumvent the lack of drug efficiency, we designed multifunctional nanoparticles based on porous silicon. Herein, we propose an innovative synthesis technique for porous silicon nanorods (pSiNRs) with three-dimensional (3D) shape-controlled nanostructure. In order to achieve an efficient administration and improved treatment against GBM cells, a porous silicon nanoplatform is designed with magnetic guidance, fluorescence tracking and a cell-penetrating peptide (CPP). A NeuroFilament Light (NFL) subunit derived 24 amino acid tubulin binding site peptide called NFL-TBS.40-63 peptide or NFL-peptide was reported to preferentially target human GBM cells compared to healthy cells. Motivated by this approach, we investigated the use of magnetic-pSiNRs covered with superparamagnetic iron oxide nanoparticles (SPIONs) for magnetic guidance, then decorated with the NFL-peptide to facilitate targeting and enhance internalization into human GBM cells. Unexpectedly, under confocal microscope imaging, the internalized multifunctional nanoparticles in GBM cells induce a remarkable exaltation of green fluorescence instead of the red native fluorescence from the dye due to a possible Förster resonance energy transfer (FRET). In addition, we showed that the uptake of NFL-peptide decorated magnetic-pSiNRs was preferential towards human GBM cells. This study presents the fabrication of magnetic-pSiNRs decorated with the NFL-peptide, which act as a remarkable candidate to treat brain tumors. This is supported by in vitro results and confocal imaging.

Recent updates on applications of Lipid-based nanoparticles for site-specific drug delivery

BACKGROUND

Site-specific drug delivery is a widespread and demanding area nowadays. Lipid-based nanoparticulate drug delivery systems have shown promising effects for targeting drugs among lymphatic systems, brain tissues, lungs, and skin. Recently, lipid nanoparticles are used for targeting the brain via the mucosal route for local therapeutic effects. Lipid nanoparticles (LNPs) can help in enhancing the efficacy and lowering the toxicities of anticancer drugs to treat the tumors, particularly in lymph after metastases of tumors. LNPs contain a non-polar core that can improve the absorption of lipophilic drugs into the lymph node and treat tumors. Cellular uptake of drugs can also be enhanced using LNPs and therefore, LNPs are the ideal carrier for treating intracellular infections such as leishmaniasis, tuberculosis and parasitic infection in the brain, etc. Furthermore, specific surface modifications with molecules like mannose, or PEG could improve the macrophage uptake and hence effectively eradicate parasites hiding in macrophages.

METHOD

An electronic literature search was conducted to update the advancements in the field of site-specific drug delivery utilizing lipid-based nanoparticles. A search of the Scopus database (https://www.scopus.com/home.uri) was conducted using the following keywords: lipid-based nanoparticles; site specific delivery.

CONCLUSION

Solid lipid nanoparticles have shown site-specific targeted delivery to various organs including the liver, oral mucosa, brain, epidermis, pulmonary and lymphatic systems. These lipid-based systems showed improved bioavailability as well as reduced side effects. Therefore, the focus of this article is to review the recent research studies on LNPs for site-specific or targeting drug delivery.

Fabrication and Assessment of Diosgenin Encapsulated Stearic Acid Solid Lipid Nanoparticles for Its Anticancer and Antidepressant Effects Using in vitro and in vivo Models

Inflammatory cascade plays a pivotal role in the onset and progression of major depressive disorder (MDD) and glioblastoma multiforme (GBM). Therefore, questing natural compounds with anti-inflammatory activity such as diosgenin can act as a double-edged sword targeting cancer and cancer-induced inflammation simultaneously. The blood–brain barrier limits the therapeutic efficiency of the drugs against intracranial pathologies including depression and brain cancers. Encapsulating a drug molecule in lipid nanoparticles can overcome this obstacle. The current study has thus investigated the anticancer and antidepressant effect of Tween 80 (P80) coated stearic acid solid lipid nanoparticles (SLNPs) encapsulating the diosgenin. Physio-chemical characterizations of SLNPs were performed to assess their stability, monodispersity, and entrapment efficiency. In vitro cytotoxic analysis of naked and drug encapsulated SLNPs on U-87 cell line indicated diosgenin IC₅₀ value to be 194.4 μM, while diosgenin encapsulation in nanoparticles slightly decreases the toxicity. Antidepressant effects of encapsulated and non-encapsulated diosgenin were comprehensively evaluated in the concanavalin-A–induced sickness behavior mouse model. Behavior test results indicate that diosgenin and diosgenin encapsulated nanoparticles significantly alleviated anxiety-like and depressive behavior. Diosgenin incorporated SLNPs also improved grooming behavior and social interaction as well as showed normal levels of neutrophils and leukocytes with no toxicity indication. In conclusion, diosgenin and diosgenin encapsulated solid lipid nanoparticles proved successful in decreasing in vitro cancer cell proliferation and improving sickness behavioral phenotype and thus merit further exploration.

Engineered Solid Lipid Nanoparticles and Nanostructured Lipid Carriers as New Generations of Blood-Brain Barrier Transmitters

The blood-brain barrier (BBB) is considered as the most challenging barrier in brain drug delivery. Indeed, there is a definite link between the BBB integrity defects and central nervous systems (CNS) disorders, such as neurodegenerative diseases and brain cancers, increasing concerns in the contemporary era because of the inability of most therapeutic approaches. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) have already been identified as having several advantages in facilitating the transportation of hydrophilic and hydrophobic agents across the BBB. This review first explains BBB functions and its challenges in brain drug delivery, followed by a brief description of nanoparticle-based drug delivery for brain diseases. A detailed presentation of recent progressions in optimizing SLNs and NLCs for controlled release drug delivery, gene therapy, targeted drug delivery, and diagnosis of neurodegenerative diseases and brain cancers is approached. Finally, the problems, challenges, and future perspectives in optimizing these carriers for potential clinical application were described briefly.

Optimizing the Design of Blood-Brain Barrier-Penetrating Polymer-Lipid-Hybrid Nanoparticles for Delivering Anticancer Drugs to Glioblastoma

PURPOSE

Chemotherapy for glioblastoma multiforme (GBM) remains ineffective due to insufficient penetration of therapeutic agents across the blood-brain barrier (BBB) and into the GBM tumor. Herein, is described, the optimization of the lipid composition and fabrication conditions for a BBB- and tumor penetrating terpolymer-lipid-hybrid nanoparticle (TPLN) for delivering doxorubicin (DOX) to GBM.

METHODS

The composition of TPLNs was first screened using different lipids based on nanoparticle properties and in vitro cytotoxicity by using 2³ full factorial experimental design. The leading DOX loaded TPLNs (DOX-TPLN) were prepared by further optimization of conditions and used to study cellular uptake mechanisms, in vitro cytotoxicity, three-dimensional (3D) glioma spheroid penetration, and in vivo biodistribution in a murine orthotopic GBM model.

RESULTS

Among various lipids studied, ethyl arachidate (EA) was found to provide excellent nanoparticle properties e.g., size, polydispersity index (PDI), zeta potential, encapsulation efficiency, drug loading, and colloidal stability, and highest anticancer efficacy for DOX-TPLN. Further optimized EA-based TPLNs were prepared with an optimal particle size (103.8 ± 33.4 nm) and PDI (0.208 ± 0.02). The resultant DOX-TPLNs showed ~ sevenfold higher efficacy than free DOX against human GBM U87-MG-RED-FLuc cells in vitro. The interaction between the TPLNs and the low-density lipoprotein receptors also facilitated cellular uptake, deep penetration into 3D glioma spheroids, and accumulation into the in vivo brain tumor regions of DOX-TPLNs.

CONCLUSION

This work demonstrated that the TPLN system can be optimized by rational selection of lipid type, lipid content, and preparation conditions to obtain DOX-TPLN with enhanced anticancer efficacy and GBM penetration and accumulation.

Lipid nanostructures for targeting brain cancer

Advancements in both material science and bionanotechnology are transforming the health care sector. To this end, nanoparticles are increasingly used to improve diagnosis, monitoring, and therapy. Huge research is being carried out to improve the design, efficiency, and performance of these nanoparticles. Nanoparticles are also considered as a major area of research and development to meet the essential requirements for use in nanomedicine where safety, compatibility, biodegradability, biodistribution, stability, and effectiveness are requirements towards the desired application. In this regard, lipids have been used in pharmaceuticals and medical formulations for a long time. The present work focuses on the use of lipid nanostructures to combat brain tumors. In addition, this review summarizes the literature pertaining to solid lipid nanoparticles (SLN) and nanostructured lipid carriers (LNC), methods of preparation and characterization, developments achieved to overcome blood brain barrier (BBB), and modifications used to increase their effectiveness.

Improving temozolomide biopharmaceutical properties in glioblastoma multiforme (GBM) treatment using GBM-targeting nanocarriers

Glioblastoma multiforme (GBM) is the most common primary brain cancer. GBM has aggressive development, and the pharmacological treatment remains a challenge due to GBM anatomical characteristics' (the blood-brain barrier and tumor microenvironment) and the increasing resistance to marketed drugs, such as temozolomide (TMZ), the first-line drug for GBM treatment. Due to physical-chemical properties such as short half-life time and the increasing resistance shown by GBM cells, high doses and repeated administrations are necessary, leading to significant adverse events. This review will discuss the main molecular mechanisms of TMZ resistance and the use of functionalized nanocarriers as an efficient and safe strategy for TMZ delivery. GBM-targeting nanocarriers are an important tool for the treatment of GBM, demonstrating to improve the biopharmaceutical properties of TMZ and repurpose its use in anti-GBM therapy. Technical aspects of nanocarriers will be discussed, and biological models highlighting the advantages and effects of functionalization strategies in TMZ anti-GBM activity. Finally, conclusions regarding the main findings will be made in the context of new perspectives for the treatment of GBM using TMZ as a chemotherapy agent, improving the sensibility and biological anti-tumor effect of TMZ through functionalization strategies.

Solid lipid nanoparticles for hydrophilic drugs

Hydrophilic drugs are proficient therapeutic agents however, delivery of these drugs is a difficult task. Hence, developing an efficient drug delivery system may require a multipronged approach. Colloidal drug delivery systems such as emulsions, liposomes, nanoemulsions, polymeric nanoparticles, and niosomes are known to enhance drug entrapment, bioavailability, and to improve the pharmacokinetic profiles of hydrophilic drugs. However, issues such as drug leakage and burst release are frequently reported with such systems. Solid lipid nanoparticles (SLNs) were developed as an alternative to the traditional colloidal drug carriers to overcome these issues. Although SLNs have been widely studied as carriers for hydrophobic drugs, delivery of hydrophilic molecules remains a challenge. Hence, the current review focuses on different approaches that have been used for the delivery of hydrophilic drugs using SLNs. It not only discusses various modifications in the traditional methods for the synthesis but also emphasizes modifications of the hydrophilic drugs itself that can help in their efficient entrapment into SLNs drug carriers.

Nanoencapsulated Doxorubicin Prevents Mucositis Development in Mice

Doxorubicin (DOX), a chemotherapy drug successfully used in the therapy of various types of cancer, is currently associated with the mucositis development, an inflammation that can cause ulcerative lesions in the mucosa of the gastrointestinal tract, abdominal pain and secondary infections. To increase the safety of the chemotherapy, we loaded DOX into nanostructured lipid carriers (NLCs). The NLC-DOX was characterized by HPLC, DLS, NTA, Zeta potential, FTIR, DSC, TEM and cryogenic-TEM. The ability of NLC-DOX to control the DOX release was evaluated through in vitro release studies. Moreover, the effect of NLC-DOX on intestinal mucosa was compared to a free DOX solution in C57BL/6 mice. The NLC-DOX showed spherical shape, high drug encapsulation efficiency (84.8 ± 4.6%), high drug loading (55.2 ± 3.4 mg/g) and low average diameter (66.0-78.8 nm). The DSC and FTIR analyses showed high interaction between the NLC components, resulting in controlled drug release. Treatment with NLC-DOX attenuated DOX-induced mucositis in mice, improving shortening on villus height and crypt depth, decreased inflammatory parameters, preserved intestinal permeability and increased expression of tight junctions (ZO-1 and Ocludin). These results indicated that encapsulation of DOX in NLCs is viable and reduces the drug toxicity to mucosal structures.

Brain-targeted, drug-loaded solid lipid nanoparticles against glioblastoma cells in culture

The aim of this study was the preparation of solid lipid nanoparticles (SLN) formed from cetyl palmitate with having targeting molecules for monocarboxylate transporter-1 (MCT-1): β-hydroxybutyric acid and anticancer agents: carmustine (BCNU) and temozolomide (TMZ) for enhanced anti-proliferation against glioblastoma multiforme (GBM). Properties including size, morphology, chemical structure, zeta potential, drug encapsulation efficacy, drug release, biocompatibility, stability were determined, and in vitro studies were done. BCNU and TMZ loaded SLNs had a hydrodynamic size of 227 nm ± 46 a zeta potential of -25 mV ± 4 with biocompatible features. The data showed rapid drug release at first and then continuous release. Nanoparticles could be stored for nine months. BCNU and TMZ loaded SLNs exhibited a remarkable increment in the antitumor activity compared to the free-drugs and induced apoptosis on U87MG cells. In addition, targeted nanoparticles were more uptaken by MCT-1 expressing brain cells. This study indicated that BCNU and TMZ loaded SLNs could act as a useful anticancer system for targeted GBM therapy.

The Prospect of Nanoparticle Systems for Modulating Immune Cell Polarization During Central Nervous System Infection

The blood-brain barrier (BBB) selectively restricts the entry of molecules from peripheral circulation into the central nervous system (CNS) parenchyma. Despite this protective barrier, bacteria and other pathogens can still invade the CNS, often as a consequence of immune deficiencies or complications following neurosurgical procedures. These infections are difficult to treat since many bacteria, such as Staphylococcus aureus, encode a repertoire of virulence factors, can acquire antibiotic resistance, and form biofilm. Additionally, pathogens can leverage virulence factor production to polarize host immune cells towards an anti-inflammatory phenotype, leading to chronic infection. The difficulty of pathogen clearance is magnified by the fact that antibiotics and other treatments cannot easily penetrate the BBB, which requires extended regimens to achieve therapeutic concentrations. Nanoparticle systems are rapidly emerging as a promising platform to treat a range of CNS disorders. Nanoparticles have several advantages, as they can be engineered to cross the BBB with specific functionality to increase cellular and molecular targeting, have controlled release of therapeutic agents, and superior bioavailability and circulation compared to traditional therapies. Within the CNS environment, therapeutic actions are not limited to directly targeting the pathogen, but can also be tailored to modulate immune cell activation to promote infection resolution. This perspective highlights the factors leading to infection persistence in the CNS and discusses how novel nanoparticle therapies can be engineered to provide enhanced treatment, specifically through modulation of immune cell polarization.

A Composite Nanosystem as a Potential Tool for the Local Treatment of Glioblastoma: Chitosan-Coated Solid Lipid Nanoparticles Embedded in Electrospun Nanofibers

Glioblastoma multiforme (GBM) is one of the most prevalent and aggressive brain tumors for which there is currently no cure. A novel composite nanosystem (CN), consisting of chitosan-coated Solid Lipid Nanoparticles (c-SLN) embedded in O-carboxymethyl chitosan (O-CMCS)-containing nanofibers (NFs), was proposed as a potential tool for the local delivery of lipophilic anti-proliferative drugs. Coacervation was selected as a solvent-free method for the preparation of stearic acid (SA) and behenic acid (BA)-based SLN (SA-SLN and BA-SLN respectively). BA-SLN, containing 0.75% w/w BA sodium salt and 3% w/w poly(vinyl alcohol) (PVA), were selected for the prosecution of the work since they are characterized by the lowest size functional to their subsequent coating and incorporation in nanofibers. BA-SLN were coated with chitosan (CS) by means of a two-step coating method based on the physical absorption of positively charged CS chains on the SLN negative surface. Nile Red (NR), chosen as the hydrophobic model dye, was dissolved in a micellar solution of BA sodium salt and then added with a coacervating solution until pH ≅ 2.5 was reached. Immunocytochemistry analyses highlighted that CS-coated BA-SLN (c-BA-SLN) exhibited a higher accumulation in human glioblastoma cells (U-373) after 6 h than CS-free BA-SLN. Finally, the c-BA-SLN dispersion was blended with a solution consisting of freely soluble polymers (O-CMCS, poly(ethylene oxide) and poloxamer) and then electrospun to obtain NFs with a mean diameter equal to 850 nm. After the NFs dissolution in an aqueous media, c-BA-SLN maintained their physicochemical properties and zeta potential.

SPION and doxorubicin-loaded polymeric nanocarriers for glioblastoma theranostics

Glioma is a type of cancer with a very poor prognosis with a survival of around 15 months in the case of glioblastoma multiforme (GBM). In order to advance in personalized medicine, we developed polymeric nanoparticles (PNP) loaded with both SPION (superparamagnetic iron oxide nanoparticles) and doxorubicin (DOX). The former being used for its potential to accumulate the PNP in the tumor under a strong magnetic field and the later for its therapeutic potential. The emulsion solvent and evaporation method was selected to develop monodisperse PNP with high loading efficiency in both SPION and DOX. Once injected in mice, a significant accumulation of the PNP was observed within the tumoral tissue under static magnetic field as observed by MRI leading to a reduction of tumor growth rate.

Role of Nanomedicine in Treatment of Brain Cancer

Background:

Drug delivery to cancerous brain is a challenging task as it is surrounded by an efficient protective barrier. The main hurdles for delivery of bioactive molecules to cancerous brain are blood brain barrier (BBB), the invasive nature of gliomas, drug resistance, and difficult brain interstitium transportation. Therefore, treatment of brain cancer with the available drug regimen is difficult and has shown little improvement in recent years.

Methods:

We searched about recent advancements in the use of nanomedicine for effective treatment of the brain cancer. We focused on the use of liposomes, nanoparticles, polymeric micelles, and dendrimers to improve brain cancer therapy.

Results:

Nanomedicines are well suited for the treatment of brain cancer owing to their highly acceptable biological, chemical, and physical properties. Smaller size of nanomedicines also enhances their anticancer potential and penetration into blood brain barrier (BBB).

Conclusion:

Recently, nanomedicine based approaches have been developed and investigated for effective treatment of brain cancer. Some of these have been translated into clinical practice, in order to attain therapeutic needs of gliomas. Future advancements in nanomedicines will likely produce significant changes in methods and practice of brain cancer therapy.

RGD-decorated solid lipid nanoparticles enhance tumor targeting, penetration and anticancer effect of asiatic acid

Aim: Asiatic acid (AA) is a promising anticancer agent, however, its delivery to glioblastoma is a major challenge. This work investigates the beneficial therapeutic efficacy of RGD-conjugated solid lipid nanoparticles (RGD-SLNs) for the selective targeting of AA to gliblastoma. Materials & methods: AA-containing RGD-SLNs were prepared using two different PEG-linker size. Targetability and efficacy were tested using monolayer cells and spheroid tumor models. Results: RGD-SLNs significantly improved cytotoxicity of AA against U87-MG monolayer cells and enhanced cellular uptake compared with non-RGD-containing SLNs. In spheroid models, AA-containing RGD-SLNs showed superior control in tumor growth, improved cytotoxicity and enhanced spheroid penetration when compared with AA alone or non-RGD-containing SLNs. Conclusion: This study illustrates the potential of AA-loaded RGD-SLNs as efficacious target-specific treatment for glioblastoma.

'Prodrug-Like' Acetylmannosamine Modified Liposomes Loaded With Arsenic Trioxide for the Treatment of Orthotopic Glioma in Mice

Glioma is one of the fatal intracranial cancers that is a huge challenge to decrease the death rate currently. The deep penetration and high accumulation of therapeutic inorganic ions into the tumor site are extremely impeded due to the existence of physiological barriers, which limits to widen the indication of some drugs such as arsenic trioxide. The previous data have confirmed that the mannose substrate (MAN) without acetyl groups facilitates vesicles to go into the brain. Given that deacetylation of Ac₄MAN groups on the surface of liposomes under the enzyme incubation occurred, namely 'prodrug-like' features of vesicles, the liposomes could more easily penetrate the BBB, target the glioma site, release arsenic trioxide, and inhibit the growth of glioma cells in the brain. Besides, the possibility of Ac₄MAN binding to Gluts could be reduced due to the steric hindrance of acetyl groups, decreasing the off-target effects of vesicles. Here, we developed 'prodrug-like' arsenic trioxide (As₂O₃, ATO)-loaded liposomes inserted with distearoyl phospho-ethanolamine-polyethylene glycol-1000-p-carboxylpheny-α-d-acetylmannosamine (DSPE-PEG-1000-Ac₄MAN), which was named Ac₄MAN-ATO-LIP. Cytotoxic experiments of liposomes indicated that the toxicity of Ac₄MAN-ATO-LIP was lower than that of free ATO but stronger than that of ATO-LIP (without insertion of DSPE-PEG-1000-Ac₄MAN). The uptake of vesicles by U87 glioma cells displayed that the cellular uptake of Ac₄MAN-Rho-LIP (labeled by rhodamine) was remarkably improved, compared with Rho-LIP. The in vivo biodistribution results showed the superiority of Ac₄MAN-Rho-LIP in enhanced intracranial accumulation. Furthermore, the treatment of orthotopic glioma in Balb/c nude mice with Ac₄MAN-ATO-LIP elongated the survival time of the animals than that with physiological saline, free ATO, or ATO-LIP, respectively. All the results suggested that the Ac₄MAN-ATO-LIP had stronger anti-glioma effects as well as lower toxicities, and may be a promising approach for the treatment of brain cancer.

Co-encapsulation of superparamagnetic nanoparticles and doxorubicin in PLGA nanocarriers: Development, characterization and in vitro antitumor efficacy in glioma cells

With a very poor prognosis and no clear etiology, glioma is the most aggressive cancer in the brain. Thanks to its versatility, nanomedicine is a promising option to overcome the limitations on chemotherapy imposed by the blood brain barrier (BBB). The objective of this paper was to obtain monitored tumor-targeted therapeutic nanoparticles (NPs). To that end, theranostic surfactant-coated polymer poly-Lactic-co-Glycolic Acid (PLGA) nanoplatform encapsulating doxorubicin hydrochloride (DOX) and superparamagnetic iron oxide NPs (SPIONs) were developed. Different non-ionic surfactants known as BBB crossing enhancers (Tween 80, Brij-35, Pluronic F68 or Vitamin E-TPGS) were used to develop 4 types of theranostic nanoplatforms, which were characterized in terms of size and morphology by DLS, TEM and STEM-HAADF analyses. Moreover, the 3-month stability test, the therapeutic efficacy against different glioma cell lines (U87-MG, 9L/LacZ and patient derived-neuronal stem cells) and the Magnetic Resonance Imaging (MRI) relaxivity were studied. Results showed that the synthesised nanoplatforms were stable at 4 °C after their lyophilization, being that of paramount importance to ensure a long-term stability in a future in vivo application. Furthermore, the theranostic nanoplatforms were efficient in the in vitro treatment of glioma cells, proving to have imaging efficacy as MRI contrast agents. Our results show an efficient loading of drugs and good value of the relaxivity. Therefore, the efficient theranostic hybrid nanoplatform developed here could be used to perform MRI-guided delivery of hydrophobic drugs.

Hydrophobic ion pairing: encapsulating small molecules, peptides, and proteins into nanocarriers

Hydrophobic ion pairing has emerged as a method to modulate the solubility of charged hydrophilic molecules ranging in class from small molecules to large enzymes. Charged hydrophilic molecules are ionically paired with oppositely-charged molecules that include hydrophobic moieties; the resulting uncharged complex is water-insoluble and will precipitate in aqueous media. Here we review one of the most prominent applications of hydrophobic ion pairing: efficient encapsulation of charged hydrophilic molecules into nano-scale delivery vehicles - nanoparticles or nanocarriers. Hydrophobic complexes are formed and then encapsulated using techniques developed for poorly-water-soluble therapeutics. With this approach, researchers have reported encapsulation efficiencies up to 100% and drug loadings up to 30%. This review covers the fundamentals of hydrophobic ion pairing, including nomenclature, drug eligibility for the technique, commonly-used counterions, and drug release of encapsulated ion paired complexes. We then focus on nanoformulation techniques used in concert with hydrophobic ion pairing and note strengths and weaknesses specific to each. The penultimate section bridges hydrophobic ion pairing with the related fields of polyelectrolyte coacervation and polyelectrolyte-surfactant complexation. We then discuss the state of the art and anticipated future challenges. The review ends with comprehensive tables of reported hydrophobic ion pairing and encapsulation from the literature.

Brain targeted delivery of anticancer drugs: prospective approach using solid lipid nanoparticles

A brain tumour is amongst most devastating and challenging condition to overcome with suitable treatment as the drug has to cross the blood-brain barrier (BBB) with several physiological barriers like opsonisation by the reticuloendothelial system. Presently various techniques such as surgical, chemotherapeutic agents, and radiotherapy techniques have performed to extend the lifespan of patients diagnosed with glioblastoma, which did not maximise the overall survival of patients with a tumour. Nanotechnology is relied upon to diminish the requirement for intrusive methods for conveyance of therapeutics to the central nervous system. Colloidal nanocarriers sizing range 1-1000 nm have been utilised to cross BBB delivers the drug at cell levels with enhanced bioavailability and reduced toxicity. However, solid lipid nanoparticles (SLNs) are considered a highly flexible carrier for more successful remedially in brain tumour. The treatment of a brain tumour via SLNs is gaining greater potency due to its inimitable size and lipidic nature. This review focuses and represents the current strategies of SLNs in the brain tumour treatment with appropriate techniques adopted are highlighted. Based on this review, the authors concluded that SLNs embrace exclusive promising lipidic nanocarrier that could be utilised to target a brain tumour effectively.

Nutlin-loaded magnetic solid lipid nanoparticles for targeted glioblastoma treatment

Aim

Glioblastoma multiforme is one of the deadliest forms of cancer, and current treatments are limited to palliative cares. The present study proposes a nanotechnology-based solution able to improve both drug efficacy and its delivery efficiency.

Materials & methods

Nutlin-3a and superparamagnetic nanoparticles were encapsulated in solid lipid nanoparticles, and the obtained nanovectors (nutlin-loaded magnetic solid lipid nanoparticle [Nut-Mag-SLNs]) were characterized by analyzing both their physicochemical properties and their effects on U-87 MG glioblastoma cells.

Results

Nut-Mag-SLNs showed good colloidal stability, the ability to cross an in vitro blood–brain barrier model, and a superior pro-apoptotic activity toward glioblastoma cells with respect to the free drug.

Conclusion

Nut-Mag-SLNs represent a promising multifunctional nanoplatform for the treatment of glioblastoma multiforme.

'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.

Chemoresistance caused by the microenvironment of glioblastoma and the corresponding solutions

Glioblastoma multiforme (GBM) is the most common and aggressive primary human brain tumor. Although comprehensive therapies combining radiotherapy and chemotherapy after surgery can prolong survival, the prognosis is still poor with a median survival of only 14.6 months. Chemoresistance is one of the major causes of relapse as well as poor survival in glioma patients. Therefore, novel strategies to overcome chemoresistance are desperately needed for improved treatment of human GBM. Recent studies have demonstrated that the tumor microenvironment plays a critical role in the chemoresistance of various tumor types, which makes it a suitable target in anti-cancer therapies, as well as a valuable biomarker for prognostic purposes. This review focuses on chemoresistance in GBM induced by stromal cells, including the endothelium of blood vessels, astrocytes, and myeloid cells, as well as non-cellular factors in the tumor microenvironment. Corresponding therapies are discussed, including progressive strategies involving 3-dimensional models integrating engineering as well as biological advances.

Enhancement of oral bioavailability of doxorubicin through surface modified biodegradable polymeric nanoparticles

Background

Doxorubicin hydrochloride (DOX·HCl), an anthracycline glycoside antibiotic, exhibits low oral bioavailability due to active efflux from intestinal P-glycoprotein receptors. The oral administration of DOX remains a challenge hence; no oral formulation for DOX is marketed, till date.

Aim of the study

To improve the oral bioavailability of DOX through, preparation of a nanoformulation i.e. PEGylated-doxorubicin(DOX)-loaded-poly-lactic-co-glycolic acid (PLGA)-Nanoparticles (NPs) and to develop and validate an ultra-high performance liquid chromatography electrospray ionization-synapt mass spectrometric bioanalytical method (UHPLC/ESI-QTOF–MS/MS) for plasma (Wistar rats) DOX quantification.

Materials and methods

For chromatography, Waters ACQUITY UPLC™ along with a BEH C-18 column (2.1 mm × 100 mm; 1.7 μm), mobile phase conditions (acetonitrile: 0.1% formic acid::1:1 v/v) and flow rate (0.20 ml/min) was used. For analyte recovery from rat plasma, a liquid–liquid extraction method (LLE), using Acetonitrile: 5 mM ammonium acetate in a ratio of 6:4 v/v at pH 3.5, was used.

Results

Nanoformulation with a particle size (183.10 ± 7.41 nm), zeta potential (− 13.10 ± 1.04 mV), drug content (42.69 ± 1.97 µg/mg) and a spherical shape and smooth surface was developed. An elution time of 1.61 and 1.75 min along with a transition at m/z 544.42/397.27 and 528.46/321.41 were observed for DOX and internal standard (IS) Daunorubicin, respectively. In addition, a linear dynamic range with r² ≥ 0.9985 over a concentration range of 1.00–2500.0 ng/ml was observed for different processes and parameters used in the study. Similarly a marked improvement i.e. 6.8 fold was observed, in PEGylated-DOX-PLGA-NPs as compared to DOX-S, in pharmacokinetics studies.

Conclusion

The promising approach of PEGylated-DOX-PLGA-NPs may provide an alternate to intravenous therapy for better patient care.

Development and Characterization of Solid Lipid Nanoparticles Loaded with a Highly Active Doxorubicin Derivative

Solid lipid nanoparticles (SLNs) comprise a versatile drug delivery system that has been developed for the treatment of a variety of diseases. The present study will investigate the feasibility of entrapping an active doxorubicin prodrug (a squalenoyl-derivative) in SLNs. The doxorubicin derivative-loaded SLNs are spherically shaped, have a mean diameter of 300-400 nm and show 85% w/w drug entrapment efficiency. The effects on cell growth of loaded SLNs, free doxorubicin and the prodrug have been examined using cytotoxicity and colony-forming assays in both human ovarian cancer line A2780 wild-type and doxorubicin-resistant cells. Further assessments as to the treatment's ability to induce cell death by apoptosis have been carried out by analyzing annexin-V staining and the activation of caspase-3. The in vitro data demonstrate that the delivery of the squalenoyl-doxorubicin derivative by SLNs increases its cytotoxic activity, as well as its apoptosis effect. This effect was particularly evident in doxorubicin-resistant cells.

Advances in the design of solid lipid nanoparticles and nanostructured lipid carriers for targeting brain diseases

Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) comprise a category of versatile drug delivery systems that have been used in the biomedical field for >25years. SLNs and NLCs have been used for the treatment of various diseases including cardiovascular and cerebrovascular, and are considered a standard treatment for the latter, due to their inherent ability to cross the blood brain barrier (BBB). In this review, a presentation of the most important brain diseases (brain cancer, ischemic stroke, Alzheimer's disease, Parkinson's disease and multiple sclerosis) is approached, followed by the basic fabrication techniques of SLNs and NLCs. A detailed description of the reported studies of the last seven years, of active and passive targeting SLNs and NLCs for the treatment of glioblastoma multiforme and of other brain cancers, as well as for the treatment of neurodegenerative diseases is also carried out. Finally, a brief description of the advantages, the disadvantages, and the future perspectives in the use of these nanocarriers is reported, aiming at giving an insight of the limitations that have to be overcome in order to result in a delivery system with high therapeutic efficacy and without the limitations of the existing nano-systems.

Effective use of nanocarriers as drug delivery systems for the treatment of selected tumors

Nanotechnology has recently gained increased attention for its capability to effectively diagnose and treat various tumors. Nanocarriers have been used to circumvent the problems associated with conventional antitumor drug delivery systems, including their nonspecificity, severe side effects, burst release and damaging the normal cells. Nanocarriers improve the bioavailability and therapeutic efficiency of antitumor drugs, while providing preferential accumulation at the target site. A number of nanocarriers have been developed; however, only a few of them are clinically approved for the delivery of antitumor drugs for their intended actions at the targeted sites. The present review is divided into three main parts: first part presents introduction of various nanocarriers and their relevance in the delivery of anticancer drugs, second part encompasses targeting mechanisms and surface functionalization on nanocarriers and third part covers the description of selected tumors, including breast, lungs, colorectal and pancreatic tumors, and applications of relative nanocarriers in these tumors. This review increases the understanding of tumor treatment with the promising use of nanotechnology.

Use of nanoparticles for glioblastoma treatment: a new approach

Glioblastoma (GBM) is a very aggressive CNS tumor with poor prognosis. Current treatment lacks efficacy indicating that new therapeutic approaches are needed. One of these new approaches is based on the use of nanoparticles (NPs) to deliver different cargos (antitumoral drugs or genetic materials) to tumoral cells. This review covers the signaling pathways altered in GBM cells to understand the rationale behind choosing new therapeutic targets and recent advances in the use of different NPs to deliver to GBM cells, both in vitro and in vivo, different therapeutic molecules. A special focus is placed on the effect of NPs on orthotopic brain tumors since this animal model represents the optimal model for translational purposes.

Physicochemical characterization of drug nanocarriers

Pharmaceutical design has enabled important advances in the prevention, treatment, and diagnosis of diseases. The use of nanotechnology to optimize the delivery of drugs and diagnostic molecules is increasingly receiving attention due to the enhanced efficiency provided by these systems. Understanding the structures of nanocarriers is crucial in elucidating their physical and chemical properties, which greatly influence their behavior in the body at both the molecular and systemic levels. This review was conducted to describe the principles and characteristics of techniques commonly used to elucidate the structures of nanocarriers, with consideration of their size, morphology, surface charge, porosity, crystalline arrangement, and phase. These techniques include X-ray diffraction, small-angle X-ray scattering, dynamic light scattering, zeta potential, polarized light microscopy, transmission electron microscopy, scanning electron microcopy, and porosimetry. Moreover, we describe some of the commonly used nanocarriers (liquid crystals, metal-organic frameworks, silica nanospheres, liposomes, solid lipid nanoparticles, and micelles) and the main aspects of their structures.

Chemotherapeutic Drugs: DNA Damage and Repair in Glioblastoma

Despite improvements in therapeutic strategies, glioblastoma (GB) remains one of the most lethal cancers. The presence of the blood-brain barrier, the infiltrative nature of the tumor and several resistance mechanisms account for the failure of current treatments. Distinct DNA repair pathways can neutralize the cytotoxicity of chemo- and radio-therapeutic agents, driving resistance and tumor relapse. It seems that a subpopulation of stem-like cells, indicated as glioma stem cells (GSCs), is responsible for tumor initiation, maintenance and recurrence and they appear to be more resistant owing to their enhanced DNA repair capacity. Recently, attention has been focused on the pivotal role of the DNA damage response (DDR) in tumorigenesis and in the modulation of therapeutic treatment effects. In this review, we try to summarize the knowledge concerning the main molecular mechanisms involved in the removal of genotoxic lesions caused by alkylating agents, emphasizing the role of GSCs. Beside their increased DNA repair capacity in comparison with non-stem tumor cells, GSCs show a constitutive checkpoint expression that enables them to survive to treatments in a quiescent, non-proliferative state. The targeted inhibition of checkpoint/repair factors of DDR can contribute to eradicate the GSC population and can have a great potential therapeutic impact aiming at sensitizing malignant gliomas to treatments, improving the overall survival of patients.

Solid lipid nanoparticles by coacervation loaded with a methotrexate prodrug: preliminary study for glioma treatment

AIM

Methotrexate-loaded biocompatible nanoparticles were tested for preliminary efficacy in glioma treatment.

MATERIALS & METHODS

Behenic acid nanoparticles, prepared by the coacervation method, were loaded with the ester prodrug didodecylmethotrexate, which was previously tested in vitro against glioblastoma human primary cultures. Nanoparticle conjugation with an ApoE mimicking chimera peptide was performed to obtain active targeting to the brain.

RESULTS & CONCLUSION

Biodistribution studies in healthy rats assessed the superiority of ApoE-conjugated formulation, which was tested on an F98/Fischer glioma model. Differences were observed in tumor growth rate (measured by MRI) between control and treated rats. In vitro tests on F98 cultured cells assessed their susceptibility to treatment, with consequent apoptosis, and allowed us to explain the apoptosis observed in glioma models.

A 3D neurovascular microfluidic model consisting of neurons, astrocytes and cerebral endothelial cells as a blood-brain barrier

The neurovascular unit is a complex, interdependent system composed of neurons and neural supporting cells, such as astrocytes, as well as cells that comprise the vascular system including endothelial cells, pericytes, and smooth muscle cells. Each cell type in the neurovascular unit plays an essential role, either in transmitting and processing neural signals or in maintaining the appropriate microenvironmental conditions for healthy neural function. In vitro neurovascular models can be useful for understanding the different roles and functions of the cells composing the neurovascular unit, as well as for assessing the effects on neural function of therapeutic compounds after crossing the endothelial barrier. Here, we report a novel three-dimensional neurovascular microfluidic model consisting of primary rat astrocytes and neurons together with human cerebral microvascular endothelial cells. These three cell types in our neurovascular chip (NVC) show distinct cell type-specific morphological characteristics and functional properties. In particular, morphological and functional analysis of neurons enables quantitative assessment of neuronal responses, while human cerebral endothelial cells form monolayers with size-selective permeability similar to existing in vitro blood-brain barrier (BBB) models.

Biodegradable Nanoparticles for Delivery of Therapeutics in CNS Infection

Despite the significant advances in neurological medicine, it remains difficult to treat ailments directly involving the brain. The blood brain barrier (BBB) is a tightly regulated, selectively permeable barrier that restricts access from the blood into the brain extracellular fluid (BEF). Many conditions such as tumors or infections in the brain are difficult to treat due to the fact that drugs and other therapeutic agents are unable to easily pass through this relatively impermeable barrier. Human Immunodeficiency Virus (HIV) presents a particular problem as it is able to remain dormant in the brain for years protected from antiretroviral drugs by the BBB. The development of nanoscale carriers over the past few decades has made possible the delivery of therapies with the potential to overcome membrane barriers and provide specific, targeted delivery. This review seeks to provide a comprehensive overview of the various aspects of nanoparticle formulation and their applications in improving the delivery efficiency of drugs, specifically antiretroviral therapeutics to the brain to treat HIV.

Dermal delivery of doxorubicin-loaded solid lipid nanoparticles for the treatment of skin cancer

OBJECTIVE

Dermal delivery of Doxorubicin (Dox) would be an ideal way in maximising drug efficiency against skin cancer accompanying with minimising side effects. We investigated the potential of Dox-loaded Solid lipid nanoparticles (SLNs) for topical delivery against skin cancer.

METHODS

In vitro and in vivo cytotoxicity of optimised formulation were evaluated on murine melanoma (B16F10) cells by MTT assay and melanoma induced Balb/C mice, respectively. Animal study followed by histological analysis.

RESULTS

Optimised formulation showed mean particle size and encapsulation efficiency (EE) of 92 nm and 86% w/w (0.86% w/w value of encapsulated Dox in the lipid matrix), respectively. FTIR experiment confirmed drug-lipid interaction interpreting the observed high EE value for Dox. In vitro and in vivo results indicated the superiority of cytotoxic performance of Dox-loaded SLN compared to Dox solution.

CONCLUSION

Our findings may open the possibilities for the topical delivery of Dox to the skin cancerous tissues.