Nose-to-brain delivery of disulfiram nanoemulsion in situ gel formulation for glioblastoma targeting therapy

Contemporary strategies in glioblastoma therapy: Recent developments and innovations

Glioblastoma multiforme (GBM) represents one of the most prevailing and aggressive primary brain tumors among adults. Despite advances in therapeutic approaches, the complex microenvironment of GBM poses significant challenges in its optimal therapy, which are attributed to immune evasion, tumor repopulation by stem cells, and limited drug penetration across the blood-brain barrier (BBB). Nanotechnology has emerged as a promising avenue for GBM treatment, offering biosafety, sustained drug release, enhanced solubility, and improved BBB penetrability. In this review, a comprehensive overview of recent advancements in nanocarrier-based drug delivery systems for GBM therapy is emphasized. The conventional and novel treatment modalities for GBM and the potential of nanocarriers to overcome existing limitations are comprehensively covered. Furthermore, the updates in the clinical landscape of GBM therapeutics are presented in addition to the current status of drugs and patents in the same context. Through a critical evaluation of existing literature, the therapeutic prospect and limitations of nanocarrier-based drug delivery strategies are highlighted offering insights into future research directions and clinical translation.

Octa-Arginine-Conjugated Liposomal Nimodipine Incorporated in a Temperature-Responsive Gel for Nasoencephalic Delivery

Nimodipine is the primary clinical drug used to treat cerebral vasospasm following subarachnoid hemorrhage. Currently, tablets have low bioavailability when taken orally, and injections contain ethanol. Therefore, we investigated a new method of nimodipine administration, namely, nasoencephalic administration. Nasal administration of nimodipine was carried out by attaching the cell-penetrating peptide octa-arginine (R8) to liposomes of nimodipine and incorporating it into a temperature-sensitive in situ gel. The prepared liposomes and gels underwent separate evaluations for in vitro characterization. In vitro release exhibited a significant slow-release effect. In vitro toad maxillary cilia model, RPMI 2650 cytotoxicity, and in vivo SD rat pathological histotoxicity experiments showed that all the dosage from the groups had no significant toxicity to toad maxillary cilia, RPMI 2650 cells, and SD rat tissues and organs, and the cilia continued to oscillate up to 694 ± 10.15 min, with the survival rate of the cells being above 85%. A transwell nasal mucosa cell model and an isolated porcine nasal mucosa model were established, and the results showed that the osmolality of the R8-modified nimodipine liposomal gel to nasal mucosal cells and isolated porcine nasal mucosa was 30.41 ± 2.14 and 65.9 ± 7.34 μg/mL, respectively, which was significantly higher than that of the NM-Solution and PEGylated nimodipine liposome gel groups. Animal fluorescence imaging studies revealed that the R8-modified nimodipine liposomal gel displayed increased brain fluorescence intensity compared to the normal liposomal gel. Pharmacokinetic results showed that after transnasal administration, the AUC(0-∞) of the R8-modified nimodipine liposomal gel was 11.662 ± 1.97 μg·mL-1, which was significantly higher than that of the plain nimodipine liposomal gel (5.499 ± 2.89 μg·mL-1). Brain-targeting experiments showed that the brain-targeting efficiencies of the PEGylated nimodipine liposome gel and R8-modified PEGylated nimodipine liposome gels were 20.44 and 33.45, respectively, suggesting that R8/PEG/Lip-NM-TSG significantly increased the brain-targeting of the drug.

Exploring intranasal drug delivery via nanocarriers: A promising glioblastoma therapy

Glioblastoma is one of the most recurring types of glioma, having the highest mortality rate among all other gliomas. Traditionally, the standard course of treatment for glioblastoma involved maximum surgical resection, followed by chemotherapy and radiation therapy. Nanocarriers have recently focused on enhancing the chemotherapeutic administration to the brain to satisfy unmet therapeutic requirements for treating brain-related disorders. Due to the significant drawbacks and high recurrence rates of gliomas, intranasal administration of nanocarrier systems presents several advantages. These include low toxicity, non-invasiveness, and the ability to cross the blood-brain barrier. By customizing their size, encasing them with mucoadhesive agents, or undergoing surface modification that encourages movement over the nose's mucosa, we can exceptionally engineer nanocarriers for intranasal administration. Olfactory and trigeminal nerves absorb drugs administered nasally and transport them to the brain, serving as the primary delivery mechanism for nose-to-brain administration. This review sums up the latest developments in chemotherapeutic nanocarriers, such as metallic nanoparticles, polymeric nanoparticles, nanogels, nano vesicular carriers, genetic material-based nanocarriers, and polymeric micelles. These nanocarriers have demonstrated efficient drug delivery from the nose to the brain, effectively overcoming mucociliary clearance. However, challenges persist, such as limitations in targeted chemotherapy and restricted drug loading capacity for intranasal administration. Additionally, the review addresses regulatory considerations and prospects for these innovative drug delivery systems.

Disulfiram attenuates cell and tissue damage and blood‒brain barrier dysfunction after intracranial haemorrhage by inhibiting the classical pyroptosis pathway

No single treatment significantly reduces the mortality rate and improves neurological outcomes after intracerebral haemorrhage (ICH). New evidence suggests that pyroptosis-specific proteins are highly expressed in the perihaematomal tissues of patients with ICH and that the disulfiram (DSF) inhibits pyroptosis. An ICH model was established in C57BL/6 mice by intracranial injection of collagenase, after which DSF was used to treat the mice. Cell model of ICH was constructed, and DSF was used to treat the cells. HE, TUNEL, Nissl, FJC and IF staining were performed to evaluate the morphology of brain tissues; Western blotting and ELISA were performed to measure the protein expression of NOD-like receptor protein 3 (NLRP3)/Caspase-1/gasdermin D (GSDMD) classical pyroptosis pathway and Toll-likereceptor4 (TLR4)/nuclear factor-kappaB (NF-κB) inflammatory signaling pathway and blood‒brain barrier-associated factoes, and the wet/dry weight method was used to determine the brain water content. The expression of proteins related to the NLRP3/Caspase-1/GSDMD pathway and the TLR4/NF-κB pathway was upregulated in tissues surrounding the haematoma compared with that in control tissues; Moreover, the expression of the blood-brain barrier structural proteins occludin and zonula occludens-1 (ZO-1) was downregulated, and the expression of Aquaporin Protein-4 (AQP4) and matrix metalloprotein 9 (MMP-9) was upregulated. DSF significantly inhibited these changes, reduced the haematoma volume, decreased the brain water content, reduced neuronal death and degeneration and improved neurological function after ICH. ICH activated the classical pyroptosis pathway and TLR4/NF-κB inflammatory pathway, disruped the expression of blood-brain barrier structural proteins, and exacerbated brain injury and neurological dysfunction. DSF inhibited these changes and exerted the therapeutic effects on pathological changes and dysfunction caused by ICH.

Current strategic arsenal and advances in nose to brain nanotheranostics for therapeutic intervention of glioblastoma multiforme

The fight against Glioblastoma multiforme (GBM) is ongoing and the long-term outlook for GBM remains challenging due to low prognosis but every breakthrough brings us closer to improving patient outcomes. Significant hurdles in GBM are heterogeneity, fortified tumor location, and blood-brain barrier (BBB), hindering adequate drug concentrations within functioning brain regions, thus leading to low survival rates. The nasal passageway has become an appealing location to commence the course of cancer therapy. Utilization of the nose-to-brain (N2B) route for drug delivery takes a sidestep from the BBB to allow therapeutics to directly access the central nervous system (CNS) and enhance drug localization in the vicinity of the tumor. This comprehensive review provides insights into pertinent anatomy and cellular organization of the nasal cavity, present-day diagnostic tools, intracranial invasive therapies, and advancements in intranasal (IN) therapies in GBM models for better clinical outcomes. Also, this review highlights groundbreaking carriers and delivery techniques that could revolutionize GBM management such as biomimetics, image guiding-drug delivery, and photodynamic and photothermal therapies for GBM management.

Enhanced localized therapeutic precision: A face-to-face folate-targeted Cu2+-mediated nanotherapy with thermosensitive sustained-release system

Safe and effective Cu2+ supplementation in local lesion is crucial for minimizing toxicity of DSF-based chemotherapy. Targeted delivery of Cu2+ appears more promising. Intraperitoneal chemotherapy for peritoneal carcinoma (PC) establishes "face-to-face" contact between targeted nanocarriers and tumor tissue. Herein, this study developed a biodegradable, injectable thermosensitive hydrogel that coencapsulating DSF submicroemulsion (DSF-SE) and folate-modified liposome loading glycyrrhizic acid-Cu (FCDL). FCDL acted as 'beneficial horse' to target the tumor-localized folate receptor, thus liberating Cu2+ in tumor nidus. The prepared FCDL and DSF-SE were found with uniform sizes (160.2 nm, 175.4 nm), low surface charge (-25.77 mV, -16.40 mV) and high encapsulation efficiency (97.93 %, 90.08 %). In vitro drug release profile of FCDL, DSF-SE and FCDL＆DSF-SE@G followed a sustained release pattern. And the release behavior of Cu2+ from FCDL was pH-related, i.e., Cu2+ was released faster under acidic condition. When FCDL and DSF-SE were loaded into an PLGA-PEG-PLGA-based hydrogel system, FCDL＆DSF-SE@G was formed to ensure separated delivery of Cu2+ and DSF in space but synchronized release over time. The rheology experiment showed a satisfactory gelling temperature of 32.7 °C. In vitro cytotoxicity study demonstrated that FCDL＆DSF-SE@G significantly lowered the IC50 of free Cu2+/DSF, Cu2+/DSF hydrogel and non-targeted analogue by almost 70 %, 65 % and 32 %, respectively. Accordingly, in tumor-bearing mice, FCDL＆DSF-SE@G augmented the tumor inhibition rates for the same formulations by 352 %, 145 % and 44 %, respectively. The main mechanism was attributed to higher uptake of FCDL and DSF-SE, resulting in increased Cu(DDTC)2 formation, ROS production and cell apoptosis. In conclusion, this targeted nanotherapy approach with dual-nanocarriers loaded hydrogel system, with its focus on face-to-face contact between nanocarriers and tumor tissues in the peritoneal cavity, holds significant promise for intraperitoneal chemotherapy in PC.

Design and Characterization of Chitosan-Based Smart Injectable Hydrogel for Improved Sustained Release of Antinarcotics

The treatment adherence of narcotics-addicted individuals with reduced incidences of relapse can be enhanced by a sustained drug release formulation of antinarcotics. So far, different drug formulations have been reported with sustained drug release periods of 28 and 35 days. To further enhance this duration, different formulations of injectable hydrogels (IHs) have been developed by combining low molecular weight (LMW) and high molecular weight (HMW) chitosan (CS) with guar gum (GG) and crosslinking them by sodium bi phosphate dibasic. The structural, morphological, and physicochemical properties of LMW-CS IH, and HMW-CS IH were evaluated using Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), and rheological, swelling, and biodegradation analysis. The HMW-CS IH showed high crosslinking, increased thermal stability, high mechanical strength, elevated swelling, and low biodegradation. The antinarcotic drugs naltrexone (NTX) and disulfiram (DSF) were loaded separately into the HMW-CS IH and LMW-CS IH. The release of NTX and DSF was investigated in phosphate buffer saline (PBS) and ethanol (0.3%, 0.4%, and 0.5%) over a 56-day period using an UV spectrophotometer. The drug release data were tested in zero-order, first-order, and Korsemeyer-Peppas mathematical models. In PBS, all prepared formulations followed non-Fickian drug release, while in ethanol, only NTX HMW-CS IH followed non-Fickian release in all three different concentrations of ethanol.

Mucoadhesive chitosan-poly (lactic-co-glycolic acid) nanoparticles for intranasal delivery of quetiapine - Development & characterization in physiologically relevant 3D tissue models

Quetiapine hemifumarate (QF) delivery to the CNS via conventional formulations is challenging due to poor solubility and lower oral bioavailability (9 %). Similarly, many other second-generation antipsychotics, such as olanzapine, clozapine, and paliperidone, have also shown low oral bioavailability of <50 %. Hence, the present work was intended to formulate QF-loaded biodegradable PLGA-NPs with appropriate surface charge modification through poloxamer-chitosan and investigate its targeting potential on RPMI-2650 cell lines to overcome the limitations of conventional therapies. QF-loaded poloxamer-chitosan-PLGA in-situ gel (QF-PLGA-ISG) was designed using emulsification and solvent evaporation techniques. Developed QF-PLGA-ISG were subjected to evaluation for particle size, PDI, zeta potential, ex-vivo mucoadhesion, entrapment efficiency (%EE), and drug loading, which revealed 162.2 nm, 0.124, +20.5 mV, 52.4 g, 77.5 %, and 9.7 %, respectively. Additionally, QF-PLGA formulation showed >90 % release within 12 h compared to 80 % of QF-suspension, demonstrating that the surfactant with chitosan-poloxamer polymers could sustainably release medicine across the membrane. Ex-vivo hemolysis study proved that developed PLGA nanoparticles did not cause any hemolysis compared to negative control. Further, in-vitro cellular uptake and transepithelial permeation were assessed using the RPMI-2650 nasal epithelial cell line. QF-PLGA-ISG not only improved intracellular uptake but also demonstrated a 1.5-2-fold increase in QF transport across RPMI-2650 epithelial monolayer. Further studies in the EpiNasal™ 3D nasal tissue model confirmed the safety and efficacy of the developed QF-PLGA-ISG formulation with up to a 4-fold increase in transport compared to plain QF after 4 h. Additionally, histological reports demonstrated the safety of optimized formulation. Finally, favorable outcomes of IN QF-PLGA-ISG formulation could provide a novel platform for safe and effective delivery of QF in schizophrenic patients.

A cascade nanoplatform for intelligent response to tumor microenvironment and collaborative cancer therapy

Disulfiram (DSF), a new potential anticancer drug, has been shown to exhibit anticancer activity dependent on the formation of CuET, the chelation product of DSF with Cu2+. However, the poor stability of DSF and insufficient physiological concentration of Cu2+ hinder its practical application. To achieve the co-delivery of DSF and Cu2+ while overcoming the inefficiency of single chemotherapy, in this study, a cascade nanoplatform, DSF/Ce6@ZIF-8@CuO2, was constructed by encapsulating DSF and chlorin e6 (Ce6, a photosensitizer) in zeolite imidazole framework-8 (ZIF-8, a nanocarrier) and then loading CuO2, which self-supplied H2O2/O2, onto DSF/Ce6@ZIF-8. By triggering the response of DSF/Ce6@ZIF-8@CuO2 to the acidic tumor microenvironment, encapsulated DSF, Ce6 and CuO2 were released to achieve multimodal synergistic treatment with enhanced DSF chemotherapy and chemodynamic/photodynamic therapy (CDT/PDT). In vitro and animal studies indicated that the designed DSF/Ce6@ZIF-8@CuO2 has strong tumor-inhibitory effects and provides a promising paradigm for designing smart nanoplatforms.

Recent Advances in Intranasal Administration for Brain-Targeting Delivery: A Comprehensive Review of Lipid-Based Nanoparticles and Stimuli-Responsive Gel Formulations

Addressing disorders related to the central nervous system (CNS) remains a complex challenge because of the presence of the blood-brain barrier (BBB), which restricts the entry of external substances into the brain tissue. Consequently, finding ways to overcome the limited therapeutic effect imposed by the BBB has become a central goal in advancing delivery systems targeted to the brain. In this context, the intranasal route has emerged as a promising solution for delivering treatments directly from the nose to the brain through the olfactory and trigeminal nerve pathways and thus, bypassing the BBB. The use of lipid-based nanoparticles, including nano/microemulsions, liposomes, solid lipid nanoparticles, and nanostructured lipid carriers, has shown promise in enhancing the efficiency of nose-to-brain delivery. These nanoparticles facilitate drug absorption from the nasal membrane. Additionally, the in situ gel (ISG) system has gained attention owing to its ability to extend the retention time of administered formulations within the nasal cavity. When combined with lipid-based nanoparticles, the ISG system creates a synergistic effect, further enhancing the overall effectiveness of brain-targeted delivery strategies. This comprehensive review provides a thorough investigation of intranasal administration. It delves into the strengths and limitations of this specific delivery route by considering the anatomical complexities and influential factors that play a role during dosing. Furthermore, this study introduces strategic approaches for incorporating nanoparticles and ISG delivery within the framework of intranasal applications. Finally, the review provides recent information on approved products and the clinical trial status of products related to intranasal administration, along with the inclusion of quality-by-design-related insights.

Potential of Nanocarrier-Associated Approaches for Better Therapeutic Intervention in the Management of Glioblastoma

Glioblastoma, commonly known as glioblastoma multiforme (GBM), is one of the deadliest and most invasive types of brain cancer. Two factors account for the majority of the treatment limitations for GBM. First, the presence of the blood-brain barrier (BBB) renders malignancy treatment ineffective, leading to recurrence without full recovery. Second, several adverse effects are associated with the drugs used in conventional GBM treatment. Recent studies have developed nanocarrier systems, such as liposomes, polymeric micelles, dendrimers, nanosuspensions, nanoemulsions, nanostructured lipid carriers, solid lipid nanocarriers, metal particles, and silica nanoparticles, which allow drug-loaded formulations to penetrate the BBB more effectively. This has opened up new possibilities for overcoming therapy issues. Extensive and methodical searches of databases such as PubMed, Science Direct, Google Scholar, and others were conducted to gather relevant literature for this work, using precise keyword combinations such as "GBM," "brain tumor," and "nanocarriers." This review provides deep insights into the administration of drugs using nanocarriers for the management of GBM and explores new advancements in nanotechnology. It also highlights how scientific developments can be explained in connection with hopeful findings about the potential of nanocarriers for the future successful management of GBM.

Enhancing the Antiproliferative Activity of Perillyl Alcohol against Glioblastoma Cell Lines through Synergistic Formulation with Natural Oils

BACKGROUND

Due to its volatility, photostability, and gastrointestinal toxicity, Perillyl Alcohol (POH), a monoterpenoid component of various plant species, is a chemotherapeutic drug with insufficient efficacy. Many naturally occurring bioactive compounds have well-known antiproliferative properties, including sefsol, jojoba, tea tree, and moringa oils.

OBJECTIVE

This study sought to develop an oil-based Self Nanoemulsifying Drug Delivery System (SNEDDS) using tween 80 as the surfactant and Dimethyl Sulfoxide (DMSO) or Polyethylene Glycol (PEG) 400 as the cosurfactant; the oils were used in a range of 10-20% to boost POH's anticancer efficacy.

METHODS

The formulations' size, charge, and impact on the viability of glioma cell lines, ANGM-CSS and A172, were evaluated.

RESULTS

The developed SNEDDS formulations ranged from 3 nm to 362 nm in size, with electronegative surface charges between 5.05 and 17.0 mV and polydispersity indices between 0.3 and 1.0.

CONCLUSION

The findings indicated that the antiproliferative effect of POH-loaded Nanoemulsion (NE) could be used as a possible anticancer therapy for glioblastoma in vitro, particularly when paired with the tested natural oils. Before asserting that this delivery technique is appropriate for glioblastoma therapy, additional in vitro and in vivo investigations are required.

Antibacterial activity of juglone @ chitosan nanoemulsion against Staphylococcus aureus and its effect on pork shelf life

Food poisoning caused by Staphylococcus aureus (S. aureus) contaminated meat has received a lot of attention. Although juglone has anti-S. aureus properties, its limited water solubility prevents it from being used in food manufacturing. Juglone @ chitosan nanoemulsion (NJ) was produced for the first time in order to increase its solubility. At the same time, it was applied to the pork model. According to the findings, NJ's particle size was 119.30 nm, its polymer dispersity index (PDI) value was 0.290, and its zeta potential was -57.3 mV. And it's stable over a 7-day storage period. The cell shape and membrane integrity of S. aureus were significantly damaged by NJ. At the same time, NJ showed extreme vigor for biofilm removal. The inclusion of NJ coating significantly reduced S. aureus, total volatile base nitrogen (TVB-N), total viable count (TVC), thiobarbituric acid reactants (TBARS), and pH in the sample when using the pork feeding model. NJ, meantime, halted the sensory evaluation's fall in meat score. Additionally, NJ demonstrated good biocompatibility in mouse acute toxicity tests. The aforementioned findings demonstrate that NJ is anticipated to become an anti-S. aureus and a novel method for coating pork preservation.

A Nanoemulgel for Nose-to-Brain delivery of Quetiapine - QbD-Enabled formulation development & in-vitro characterization

Second-generation antipsychotics, quetiapine hemifumarate (QF), exhibited highly active against negative and positive signs of psychosis. However, contemporary reports have shown that long-term therapy with QF causes lethal thrombocytopenia and leukopenia. Hence, to circumvent the drawbacks of available therapies, the current work aimed to design a QF-loaded biodegradable nanoemulsion (QF-NE) with suitable surface charge modification by poloxamer-chitosan and evaluate its targeting efficiency against RPMI-2650 cell lines. QF-loaded poloxamer-chitosan in-situ gel (QF-Nanoemulgel) was formulated through the O/W emulsification aqueous titration technique and optimized using the QbD approach. Optimized QF-Nanoemulgel subjected to evaluate for globule size, PDI, zeta potential, %T, viscosity, %EE, and ex-vivo mucoadhesive strength were found to be 15.0 ± 0.3 nm, 0.05 ± 0.001, -18.3 ± 0.2 mV, 99.8 ± 0.8 %, 13.5 ± 2.1 cP, 69.0 ± 1.5 %, and 43.7 ± 1.5 g, respectively. QF-Nanoemulgel revealed sustained release and obeyed zero-order kinetics compared to QF-NE and QF-suspension. Additionally, nanoformulations treated blood samples did not cause hemolytic activity compared to drug and negative control after 10 h treatment. Further, in-vitro cytotoxicity, cellular uptake, and permeation of 12.5 and 25 μM QF-Nanoemulgel were assessed on RPMI-2650 cells and discovered nontoxic with 0.55 ± 0.02 µg and 1.1 ± 0.04 µg cellular permeation, respectively, which ensured the safety and potency of QF-Nanogel. Current research revealed the successful development of intranasal QF-Nanoemulgel as a novel dosage form for the safe and effective delivery of QF in schizophrenia patients.

High-capacity glycol chitosan-based nanoemulsion for efficient delivery of disulfiram

Disulfiram (DS) is an anti-alcoholism drug capable of acting against important and hard-to-treat cancers. The drug's relative instability and variable absorption/distribution have led to its variable pharmacokinetics and suboptimal exposure. Hence, it was hypothesised that a nano-enabled form of DS might be able to overcome such limitations. Encapsulation of the labile DS was achieved with quaternary ammonium palmitoyl glycol chitosan (GCPQ) to form a high-capacity, soybean oil-based DS-GCPQ nanoemulsion. DS-GCPQ showed capability of oil-loading up to 50% v/v for a stable entrapment of high drug content. With increasing oil content (10 to 50% v/v), the mean particle size and polydispersity index were also increased (166 to 351 nm and 0.14 to 0.22, respectively) for a given amount of GCPQ. Formulations showed a highly positive particle surface charge (50.9 ± 1.3 mV), contributing to the colloidal stability of the individual particles. DS-GCPQ showed marked cytotoxicity against pancreatic cancer cell lines with enhanced activity in the presence of copper. An intravenous pharmacokinetic study of DS-GCPQ in vivo showed improved plasma drug stability with a DS half-life of 17 min. Prolonged survival was seen in tumour-bearing animals treated with DS-GCPQ supplemented with copper. In conclusion, DS-GCPQ nanoemulsion has the potential to be developed further for cancer therapeutic purposes.

Addressing the gaps in homeostatic mechanisms of copper and copper dithiocarbamate complexes in cancer therapy: a shift from classical platinum-drug mechanisms

The platinum drug, cisplatin, is considered as among the most successful medications in cancer treatment. However, due to its inherent toxicity and resistance limitations, research into other metal-based non-platinum anticancer medications with diverse mechanisms of action remains an active field. In this regard, copper complexes feature among non-platinum compounds which have shown promising potential as effective anticancer drugs. Moreover, the interesting discovery that cancer cells can alter their copper homeostatic processes to develop resistance to platinum-based treatments leads to suggestions that some copper compounds can indeed re-sensitize cancer cells to these drugs. In this work, we review copper and copper complexes bearing dithiocarbamate ligands which have shown promising results as anticancer agents. Dithiocarbamate ligands act as effective ionophores to convey the complexes of interest into cells thereby influencing the metal homeostatic balance and inducing apoptosis through various mechanisms. We focus on copper homeostasis in mammalian cells and on our current understanding of copper dysregulation in cancer and recent therapeutic breakthroughs using copper coordination complexes as anticancer drugs. We also discuss the molecular foundation of the mechanisms underlying their anticancer action. The opportunities that exist in research for these compounds and their potential as anticancer agents, especially when coupled with ligands such as dithiocarbamates, are also reviewed.

Cellulose derivatives and natural gums as gelling agents for preparation of emulgel-based dosage forms: A brief review

Incorporation of an emulsion onto a gel base develops a drug delivery system with improved characteristics, known as emulgel, that can envelop both hydrophilic and lipophilic molecules, and therefore increase stability and penetration of topical formulations. Such a drug delivery system provides controlled drug release that has more patient compliance and higher therapeutic efficacy. Emulgel is prepared in three main stages, preparation of water-in-oil or oil-in-water emulsion, providing the gel base, and incorporation of prepared emulsion onto gel base with continuous stirring. Various materials such as different oils (e.g. sesame oil, balsam oil, and mineral oil), emulsifiers (e.g. Tween® and Span® as the non-ionic surfactant, polyvinyl alcohol), and gelling agents including cellulose derivatives such as hydroxypropyl methylcellulose (HPMC), hydroxyethylcellulose (HEC) and carboxymethyl cellulose (CMC) in different concentrations are used in emulgel preparation. The physical properties, particle size distribution, spreadability, permeation, and drug release rate are evaluated in their development and characterization. They are used in skin disorders and other diseases such as chronic anal fisher. Also, anti-acne, analgesic, and anti-inflammatory drugs have been formulated as emulgel delivery system and their effects have been studied. In this article, the subject is to review the characteristics, preparation methods, and therapeutic efficacy as well as the potential clinical use of emulgels.

Nose-to-Brain Targeting via Nanoemulsion: Significance and Evidence

Background: Non-invasive and patient-friendly nose-to-brain pathway is the best-suited route for brain delivery of therapeutics as it bypasses the blood–brain barrier. The intranasal pathway (olfactory and trigeminal nerves) allows the entry of various bioactive agents, delivers a wide array of hydrophilic and hydrophobic drugs, and circumvents the hepatic first-pass effect, thus targeting neurological diseases in both humans and animals. The olfactory and trigeminal nerves make a bridge between the highly vascularised nasal cavity and brain tissues for the permeation and distribution, thus presenting a direct pathway for the entry of therapeutics into the brain. Materials: This review portrays insight into recent research reports (spanning the last five years) on the nanoemulsions developed for nose-to-brain delivery of actives for the management of a myriad of neurological disorders, namely, Parkinson’s disease, Alzheimer’s, epilepsy, depression, schizophrenia, cerebral ischemia and brain tumours. The information and data are collected and compiled from more than one hundred Scopus- and PubMed-indexed articles. Conclusions: The olfactory and trigeminal pathways facilitate better biodistribution and bypass BBB issues and, thus, pose as a possible alternative route for the delivery of hydrophobic, poor absorption and enzyme degradative therapeutics. Exploring these virtues, intranasal nanoemulsions have proven to be active, non-invasiveand safe brain-targeting cargos for the alleviation of the brain and other neurodegenerative disorders.

Effect of Disulfiram and Copper Plus Chemotherapy vs Chemotherapy Alone on Survival in Patients With Recurrent Glioblastoma: A Randomized Clinical Trial

Importance

Disulfiram has demonstrated broad antitumoral effect in several preclinical studies. One of the proposed indications is for the treatment of glioblastoma.

Objective

To evaluate the efficacy and safety of disulfiram and copper as add-on to alkylating chemotherapy in patients with recurrent glioblastoma.

Design, Setting, and Participants

This was a multicenter, open-label, randomized phase II/III clinical trial with parallel group design. Patients were recruited at 7 study sites in Sweden and 2 sites in Norway between January 2017 and November 2020. Eligible patients were 18 years or older, had a first recurrence of glioblastoma, and indication for treatment with alkylating chemotherapy. Patients were followed up until death or a maximum of 24 months. The date of final follow-up was January 15, 2021. Data analysis was performed from February to September 2022.

Interventions

Patients were randomized 1:1 to receive either standard-of-care (SOC) alkylating chemotherapy alone, or SOC with the addition of disulfiram (400 mg daily) and copper (2.5 mg daily).

Main Outcomes and Measures

The primary end point was survival at 6 months. Secondary end points included overall survival, progression-free survival, adverse events, and patient-reported quality of life.

Results

Among the 88 patients randomized to either SOC (n = 45) or SOC plus disulfiram and copper (n = 43), 63 (72%) were male; the mean (SD) age was 55.4 (11.5) years. There was no significant difference between the study groups (SOC vs SOC plus disulfiram and copper) in 6 months survival (62% [26 of 42] vs 44% [19 of 43]; P = .10). Median overall survival was 8.2 months (95% CI, 5.4-10.2 months) with SOC and 5.5 months (95% CI, 3.9-9.3 months) with SOC plus disulfiram and copper, and median progression-free survival was 2.6 months (95% CI, 2.4-4.6 months) vs 2.3 months (95% CI, 1.7-2.6 months), respectively. More patients in the SOC plus disulfiram and copper group had adverse events grade 3 or higher (34% [14 of 41] vs 11% [5 of 44]; P = .02) and serious adverse events (41% [17 of 41] vs 16% [7 of 44]; P = .02), and 10 patients (24%) discontinued disulfiram treatment because of adverse effects.

Conclusions and Relevance

This randomized clinical trial found that among patients with recurrent glioblastoma, the addition of disulfiram and copper to chemotherapy, compared with chemotherapy alone, resulted in significantly increased toxic effects, but no significant difference in survival. These findings suggest that disulfiram and copper is without benefit in patients with recurrent glioblastoma.

Trial Registration

ClinicalTrials.gov Identifier: NCT02678975; EUDRACT Identifier: 2016-000167-16.

Intranasal Polymeric and Lipid-Based Nanocarriers for CNS Drug Delivery

Nanomedicine is currently focused on the design and development of nanocarriers that enhance drug delivery to the brain to address unmet clinical needs for treating neuropsychiatric disorders and neurological diseases. Polymer and lipid-based drug carriers are advantageous for delivery to the central nervous system (CNS) due to their safety profiles, drug-loading capacity, and controlled-release properties. Polymer and lipid-based nanoparticles (NPs) are reported to penetrate the blood–brain barrier (BBB) and have been extensively assessed in in vitro and animal models of glioblastoma, epilepsy, and neurodegenerative disease. Since approval by the Food and Drug Administration (FDA) of intranasal esketamine for treatment of major depressive disorder, intranasal administration has emerged as an attractive route to bypass the BBB for drug delivery to the CNS. NPs can be specifically designed for intranasal administration by tailoring their size and coating with mucoadhesive agents or other moieties that promote transport across the nasal mucosa. In this review, unique characteristics of polymeric and lipid-based nanocarriers desirable for drug delivery to the brain are explored in addition to their potential for drug repurposing for the treatment of CNS disorders. Progress in intranasal drug delivery using polymeric and lipid-based nanostructures for the development of treatments of various neurological diseases are also described.

Nanoemulgel: A Novel Nano Carrier as a Tool for Topical Drug Delivery

Nano-emulgel is an emerging drug delivery system intended to enhance the therapeutic profile of lipophilic drugs. Lipophilic formulations have a variety of limitations, which includes poor solubility, unpredictable absorption, and low oral bioavailability. Nano-emulgel, an amalgamated preparation of different systems aims to deal with these limitations. The novel system prepared by the incorporation of nano-emulsion into gel improves stability and enables drug delivery for both immediate and controlled release. The focus on nano-emulgel has also increased due to its ability to achieve targeted delivery, ease of application, absence of gastrointestinal degradation or the first pass metabolism, and safety profile. This review focuses on the formulation components of nano-emulgel for topical drug delivery, pharmacokinetics and safety profiles.

A Comprehensive Review on Nanomedicine: Promising Approach for Treatment of Brain Tumor through Intranasal Administration

Brain tumors have become one of the deadliest cancers; however, their treatment is still limited by conventional approaches. Brain tumors, among other CNS diseases, are the most lethal form of cancer due to ineffective diagnosis and profiling. The major limiting factor in treating brain tumors is the blood-brain barrier (BBB), and the required therapeutic concentration is not achieved. Hence, most drugs are prescribed at higher doses, which have several unwanted side effects. Nanotechnology has emerged as an interesting and promising new approach for treating neurological disorders, including brain tumors, with the potential to overcome concerns related to traditional therapeutic approaches. Moreover, biomimetic nanomaterials have been introduced to successfully cross the blood-brain barrier and be consumed by deep skin cancer for imaging brain tumors using multimodal functional nanostructures for more specific and reliable medical assessment. These nanomedicines can address several challenges by enhancing the bioavailability of therapeutics through controlled pharmacokinetics and pharmacodynamics. Further nasal drug delivery has been considered as an alternative approach for the brain's targeting for the treatment of several CNS diseases. A drug can be directly delivered to the brain by bypassing the BBB through intranasal administration. This review discusses intranasal nanomedicine-based therapies for brain tumor targeting, which can be explored from different perspectives.

Disulfiram: A Food and Drug Administration-approved multifunctional role in synergistically drug delivery systems for tumor treatment

Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug for the treatment of alcoholism, has been found to have antitumor activity. DSF showed better antitumor efficiency when it was used in combination with certain antitumor drugs. DSF plays an important role in cancer treatment. It has been used as multidrug resistance (MDR) modulator to reverse MDR and can also combine with copper ions (Cu²⁺), which will produce copper diethyldithiocarbamate (Cu[DDC]₂) complex with antitumor activity. The synergistic targeted drug delivery for cancer treatment based on DSF, especially the combination with exogenous Cu²⁺ and its forms of administration, has attracted extensive attention in the biomedical field. In this review, we summarize these synergistic delivery systems, in the hope that they will contribute to the continuous optimization and development of more advanced drug delivery systems. Furthermore, we discuss the current limitation and future directions of DSF-based drug delivery systems in the field of tumor therapy. Hopefully, our work may inspire further innovation of DSF-based antitumor drug delivery systems.

New Drug Delivery Systems Developed for Brain Targeting

The blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (B_CSF) are two of the most complex and sophisticated concierges that defend the central nervous system (CNS) by numerous mechanisms. While they maintain the neuro-ecological homeostasis through the regulated entry of essential biomolecules, their conservative nature challenges the entry of most of the drugs intended for CNS delivery. Targeted delivery challenges for a diverse spectrum of therapeutic agents/drugs (non-small molecules, small molecules, gene-based therapeutics, protein and peptides, antibodies) are diverse and demand specialized delivery and disease-targeting strategies. This review aims to capture the trends that have shaped the current brain targeting research scenario. This review discusses the physiological, neuropharmacological, and etiological factors that participate in the transportation of various drug delivery cargoes across the BBB/B_CSF and influence their therapeutic intracranial concentrations. Recent research works spanning various invasive, minimally invasive, and non-invasive brain- targeting approaches are discussed. While the pre-clinical outcomes from many of these approaches seem promising, further research is warranted to overcome the translational glitches that prevent their clinical use. Non-invasive approaches like intranasal administration, P-glycoprotein (P-gp) inhibition, pro-drugs, and carrier/targeted nanocarrier-aided delivery systems (alone or often in combination) hold positive clinical prospects for brain targeting if explored further in the right direction.

Leveraging disulfiram to treat cancer: Mechanisms of action, delivery strategies, and treatment regimens

Disulfiram (DSF) has been used as an alcoholism drug for 70 years. Recently, it has attracted increasing attention owing to the distinguished anticancer activity, which can be further potentiated by the supplementation of Cu²⁺. Although encouraging anticancer results are obtained in lab, the clinical outcomes of oral DSF are not satisfactory, which urges an in-depth understanding of the underlying mechanisms, bottlenecks, and proposal of potential methods to address the dilemma. In this review, a critical summarization of various molecular biological anticancer mechanisms of DSF/Cu²⁺ is provided and the predicament of orally delivering DSF in clinical oncotherapy is explained by the metabolic barriers. We highlight the recent advances in the DSF/Cu²⁺ delivery strategies and the emerging treatment regimens for cancer treatment. Last but not the least, we summarize the clinical trials regarding DSF and make a prospect of DSF/Cu-based cancer therapy.

Repurposing Disulfiram for Targeting of Glioblastoma Stem Cells: An In Vitro Study

Mesenchymal glioblastoma stem cells (GSCs), a subpopulation in glioblastoma that are responsible for therapy resistance and tumor spreading in the brain, reportedly upregulate aldehyde dehydrogenase isoform-1A3 (ALDH1A3) which can be inhibited by disulfiram (DSF), an FDA-approved drug formerly prescribed in alcohol use disorder. Reportedly, DSF in combination with Cu2+ ions exerts multiple tumoricidal, chemo- and radio-therapy-sensitizing effects in several tumor entities. The present study aimed to quantify these DSF effects in glioblastoma stem cells in vitro, regarding dependence on ALDH1A3 expression. To this end, two patient-derived GSC cultures with differing ALDH1A3 expression were pretreated (in the presence of CuSO4, 100 nM) with DSF (0 or 100 nM) and the DNA-alkylating agent temozolomide (0 or 30 µM) and then cells were irradiated with a single dose of 0-8 Gy. As read-outs, cell cycle distribution and clonogenic survival were determined by flow cytometry and limited dilution assay, respectively. As a result, DSF modulated cell cycle distribution in both GSC cultures and dramatically decreased clonogenic survival independently of ALDH1A3 expression. This effect was additive to the impairment of clonogenic survival by radiation, but not associated with radiosensitization. Of note, cotreatment with temozolomide blunted the DSF inhibition of clonogenic survival. In conclusion, DSF targets GSCs independent of ALDH1A3 expression, suggesting a therapeutic efficacy also in glioblastomas with low mesenchymal GSC populations. As temozolomide somehow antagonized the DSF effects, strategies for future combination of DSF with the adjuvant standard therapy (fractionated radiotherapy and concomitant temozolomide chemotherapy followed by temozolomide maintenance therapy) are not supported by the present study.