In Situ Hexosomal Gel as a Promising Tool to Ameliorate the Transnasal Brain Delivery of Vinpocetine: Central Composite Optimization and In Vivo Biodistribution

The nasal route for nose-to-brain drug delivery: advanced nasal formulations for CNS disorders

INTRODUCTION

The nasal route offers a feasible alternative to oral and/or parenteral administration, providing a noninvasive route to achieve nose-to-brain drug delivery involving the olfactory and trigeminal nerves, and facilitating local or systemic drug action. Conventional liquid nasal dosage forms have not managed to bridge the gaps of precise dosing and targeted central nervous system (CNS) delivery, while more sophisticated formulation approaches are being explored for brain targeting, aiming to enhance bioavailability and therapeutic efficacy.

AREAS COVERED

This review focuses on preclinical and clinical evaluation of microemulsions, in-situ gels, nasal powders, and nanocarrier-based formulations. Key pharmacokinetic and pharmacodynamic findings are discussed to evaluate their potential and limitations in improving drug bioavailability and CNS targeting. The existing regulatory framework for approval of products for nose-to-brain drug delivery is also addressed and relative hurdles are discussed.

EXPERT OPINION

While nasal drug delivery holds great promise for CNS therapeutics, key challenges remain, including formulation stability, mucosal permeability, patient adherence. Future research should prioritize improving targeting efficiency, overcoming mucociliary clearance, developing user-friendly pharmaceutical products. Personalized medicine and smart delivery systems could further enhance drug targeting and minimize side effects. Continued research and regulatory advancements are essential to fully realize nasal delivery's perspective in CNS therapeutics.

Quality by design-based optimization of teriflunomide and quercetin combinational topical transferosomes for the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is an immune-mediated inflammatory disease. Combination therapy is anticipated to surpass monotherapy by targeting multiple pathways involved in RA progression. The present aim is to develop a combination of Teriflunomide (TFD) and Quercetin (QCN) loaded transferosomal gel to enhance permeability and achieve localized delivery to joint tissues. TFD or QCN transferosomes were optimized employing a 3-level, 3-factorial design Box-Behnken design (BBD). The transferosomes exhibited sustained in-vitro drug release. The topical combination gel underwent thorough evaluation of rheology, and also ex-vivo studies showed enhanced permeability through rat skin. The synergistic combination of TFD and QCN effectively suppressed NO, TNF-α and IL-6 levels in in-vitro RAW 264.7 cells. The cytotoxicity in HaCaT cell lines indicates non-toxicity of the gel, further confirmed by skin irritation study conducted in rats. The in-vivo anti-arthritic activity was evaluated in complete freund's adjuvant induced rat paw edema model illustrates the effectiveness of the combination transferosomal gel compared to other treatment groups. In conclusion, the topical delivery of TFD and QCN combination transferosomal gel demonstrated anti-arthritic activity through localized delivery whichallows for dose reduction, thereby may reduce the systemic drug exposure and mitigate the side effects associated with oral administration of TFD.

Recent opportunities and application of gellan gum based drug delivery system for intranasal route

OBJECTIVES

In the recent years, in-situ hydrogel based on gellan gum has been investigated for delivery of various drug molecules particularly to treat neurological disorders via intranasal route. The major objective of the present manuscript is to review the recent research studies exploring gellan gum as ionic triggered in-situ gel for intranasal administration to enhance absorption of drugs and to increase their therapeutic efficacy.

METHODS

This review include literature from 1982 to 2023 and were collected from various scientific electronic databases like Scopus, PubMed and Google Scholar to review source, chemistry, ionotropic gelation mechanism, and recent research studies for gellan gum based in-situ hydrogel for intransasl administration.Keywords such as gellan gum, in-situ hydrogel, intranasal administration and brain targeting were used to search literature. The present review included the research studies which explored gellan gum based in-situ gel for intranasal drug delivery.

RESULTS

The findings have shown enhanced biavailability of various drugs upon intranasal administration using gellan-gum based in-situ hydrogel.Moreover, the review indicated that intranasal administration of in-situ hydrogel facilitate to overcome blood brain barrier effectively. Hence, significantly higher drug concentration was found to be achieved in brain tissues upon intranasal administration than that of other routes like oral and intravenous.

CONCLUSION

The present work conducted a comprehensive review for gellan gum based in-situ hydrogel particularly for intransal administration to overcome BBB. The study concluded that gellan gum based in-situ hydrogel could be potential promising delivery system for intranasal administration to improve bioavailability and efficacy of drugs specifically to treat neurological disorders.

Recent Advances in the Use of Cubosomes as Drug Carriers with Special Emphasis on Topical Applications

Topical drug delivery employing drug nanocarriers has shown prominent results in treating topical ailments, especially those confined to the skin and eyes. Conventional topical formulations persist with drug and disease-related challenges during treatment. Various nanotechnology-driven approaches have been adopted to mitigate the issues associated with conventional formulations. Among these, cubosomes have shown potential applications owing to their liquid crystalline structure, which aids in bioadhesion, retention, sustained release, and loading hydrophilic and hydrophobic moieties. The phase transition behavior of glyceryl monooleate, the concentration of stabilizers, and critical packing parameters are crucial parameters that affect the formation of cubosomes. Microfluidics-based approaches constitute a recent advance in technologies for generating stable cubosomes. This review covers the recent topical applications of cubosomes for treating skin (psoriasis, skin cancer, cutaneous candidiasis, acne, and alopecia) and eye (fungal keratitis, glaucoma, conjunctivitis, and uveitis) diseases. The article summarizes the manufacturing and biological challenges (skin and ocular barriers) that must be considered and encountered for successful clinical outcomes. The patented products are successful examples of technological advancements within cosmeceuticals that support various topical applications with cubosomes in the pharmaceutical field.

Mucoadhesive Chitosan Composite Sponge as a Carrier for β-Sitosterol Cubosomes for Thermal Burn Treatment

Our study aimed to explore the potential of using nanostructured lipid carriers (NLCs) to enhance the topical administration of β-sitosterol, a bioactive that is poorly soluble in water. Here, we have taken advantage of the unique characteristics that cubosomes have to provide as a drug delivery system. These characteristics include a large surface area, thermal stability, and the capacity to encapsulate molecules that are hydrophobic, amphiphilic, and hydrophilic. The cubosomal formulation was optimized by building a central composite design. The optimum dispersion exhibited a particle size of 88.3 nm, a zeta potential of -43, a polydispersity index of 0.358, and drug entrapment of 95.6%. It was composed of 15% w/w oleic acid and 5% w/w pluronic F127. The optimized cubosome dispersion was incorporated into a sponge formulation. The optimized cubosome sponge achieved a higher drug release compared with the cubosome dispersion. The SEM micrograph of the selected sponge showed that it has an interwoven irregular fibrous lamellar structure with low density and high porosity. The in-vivo data revealed that topical application of the β-sitosterol cubosomal sponge showed significant higher wound closure percentage relative to the β-sitosterol product (Mebo)®.

Lipid and Transcriptional Regulation in a Parkinson's Disease Mouse Model by Intranasal Vesicular and Hexosomal Plasmalogen-Based Nanomedicines

Plasmalogens (vinyl-ether phospholipids) are an emergent class of lipid drugs against various diseases involving neuro-inflammation, oxidative stress, mitochondrial dysfunction, and altered lipid metabolism. They can activate neurotrophic and neuroprotective signaling pathways but low bioavailabilities limit their efficiency in curing neurodegeneration. Here, liquid crystalline lipid nanoparticles (LNPs) are created for the protection and non-invasive intranasal delivery of purified scallop-derived plasmalogens. The in vivo results with a transgenic mouse Parkinson's disease (PD) model (characterized by motor impairments and α-synuclein deposition) demonstrate the crucial importance of LNP composition, which determines the self-assembled nanostructure type. Vesicle and hexosome nanostructures (characterized by small-angle X-ray scattering) display different efficacy of the nanomedicine-mediated recovery of motor function, lipid balance, and transcriptional regulation (e.g., reduced neuro-inflammation and PD pathogenic gene expression). Intranasal vesicular and hexosomal plasmalogen-based LNP treatment leads to improvement of the behavioral PD symptoms and downregulation of the Il6, Il33, and Tnfa genes. Moreover, RNA-sequencing and lipidomic analyses establish a dramatic effect of hexosomal nanomedicines on PD amelioration, lipid metabolism, and the type and number of responsive transcripts that may be implicated in neuroregeneration.

The prescription design and key properties of nasal gel for CNS drug delivery: A review

Central nervous system (CNS) diseases are among the major health problems. However, blood-brain barrier (BBB) makes traditional oral and intravenous delivery of CNS drugs inefficient. The unique direct connection between the nose and the brain makes nasal administration a great potential advantage in CNS drugs delivery. However, nasal mucociliary clearance (NMCC) limits the development of drug delivery systems. Appropriate nasal gel viscosity alleviates NMCC to a certain extent, gels based on gellan gum, chitosan, carbomer, cellulose and poloxamer have been widely reported. However, nasal gel formulation design and key properties for alleviating NMCC have not been clearly discussed. This article summarizes gel formulations of different polymers in existing nasal gel systems, and attempts to provide a basis for researchers to conduct in-depth research on the key characteristics of gel matrix against NMCC.

Intranasal mask for protecting the respiratory tract against viral aerosols

The spread of many infectious diseases relies on aerosol transmission to the respiratory tract. Here we design an intranasal mask comprising a positively-charged thermosensitive hydrogel and cell-derived micro-sized vesicles with a specific viral receptor. We show that the positively charged hydrogel intercepts negatively charged viral aerosols, while the viral receptor on vesicles mediates the entrapment of viruses for inactivation. We demonstrate that when displaying matched viral receptors, the intranasal masks protect the nasal cavity and lung of mice from either severe acute respiratory syndrome coronavirus 2 or influenza A virus. With computerized tomography images of human nasal cavity, we further conduct computational fluid dynamics simulation and three-dimensional printing of an anatomically accurate human nasal cavity, which is connected to human lung organoids to generate a human respiratory tract model. Both simulative and experimental results support the suitability of intranasal masks in humans, as the likelihood of viral respiratory infections induced by different variant strains is dramatically reduced.

Recent Advances in the Development of Liquid Crystalline Nanoparticles as Drug Delivery Systems

Due to their distinctive structural features, lyotropic nonlamellar liquid crystalline nanoparticles (LCNPs), such as cubosomes and hexosomes, are considered effective drug delivery systems. Cubosomes have a lipid bilayer that makes a membrane lattice with two water channels that are intertwined. Hexosomes are inverse hexagonal phases made of an infinite number of hexagonal lattices that are tightly connected with water channels. These nanostructures are often stabilized by surfactants. The structure's membrane has a much larger surface area than that of other lipid nanoparticles, which makes it possible to load therapeutic molecules. In addition, the composition of mesophases can be modified by pore diameters, thus influencing drug release. Much research has been conducted in recent years to improve their preparation and characterization, as well as to control drug release and improve the efficacy of loaded bioactive chemicals. This article reviews current advances in LCNP technology that permit their application, as well as design ideas for revolutionary biomedical applications. Furthermore, we have provided a summary of the application of LCNPs based on the administration routes, including the pharmacokinetic modulation property.

Recent advances in versatile inverse lyotropic liquid crystals

Owing to the rapid and significant progress in advanced materials and life sciences, nanotechnology is increasingly gaining in popularity. Among numerous bio-mimicking carriers, inverse lyotropic liquid crystals are known for their unique properties. These carriers make accommodation of molecules with varied characteristics achievable due to their complicated topologies. Besides, versatile symmetries of inverse LCNPs (lyotropic crystalline nanoparticles) and their aggregating bulk phases allow them to be applied in a wide range of fields including drug delivery, food, cosmetics, material sciences etc. In this review, in-depth summary, discussion and outlook for inverse lyotropic liquid crystals are provided.

Cubosomes and Hexosomes as Novel Nanocarriers for Bioactive Compounds

Cubosomes and hexosomes are nanostructured liquid crystalline particles, known as biocompatible nanocarriers for drug delivery. In recent years, there has been good interest in using cubosomes and hexosomes for the delivery of bioactive compounds in functional foods. These systems feature thermodynamic stability, encapsulate both hydrophobic and hydrophilic substances, and have a high tolerance to environmental stresses and potential for controlled release. This review outlines the recent advances in cubosomes and hexosomes in the food industry, focusing on their structure, composition, formation mechanisms, and factors influencing phase transformation between cubosomes and hexosomes. The potential applications especially for the bioactive delivery are presented. The integration of cubosomes and hexosomes with other emerging encapsulation technologies such as surface coating, gelation, and incorporation of polymers are also discussed.

Photodynamic therapy fortified with topical oleyl alcohol-based transethosomal 8-methoxypsoralen for ameliorating vitiligo: Optimization and clinical study

Vitiligo is a common autoimmune skin disorder that is characterized by patchy depigmentation of the skin due to melanocytes and melanin loss. Herein, photodynamic therapy mediated 8-methoxypsoralen (8-MOP), has been used fortified with topical oleyl alcohol-based transethosomes; to overcome the poor solubility and adverse effects associated with 8-MOP oral delivery. A 2³ factorial design was used to study the formulation variables. In vitro and ex-vivo characterization besides a clinical study were conducted to assess therapeutic efficacy of the formulation. Results revealed that transethosomes were superior to transfersomes regarding drug protection from degradation. The optimized transethosomal formulation, composed of 50 mg oleyl alcohol, 10 mg Tween 80® and 20% v/v ethanol, exhibited high entrapment efficiency (83.87 ± 4.1%) and drug loading (105.0 ± 0.2%). Moreover, it showed small vesicular size (265.0 ± 2.9 nm) and PDI (0.19). The formulation depicted core and shell structure, high deformability index (12.45 ± 0.7 mL/s) and high ex-vivo skin permeation. The topical application of the developed 8-MOP transethosomal gel enhanced the effect of NB UVB radiation in the treatment of vitiligo patients and exhibited no side effects. Hence, it can be used as a future strategy for delivering 8-MOP without the need of systemic application.

Scrutinizing the Feasibility of Nonionic Surfactants to Form Isotropic Bicelles of Curcumin: a Potential Antiviral Candidate Against COVID-19

Investigating bicelles as an oral drug delivery system and exploiting their structural benefits can pave the way to formulate hydrophobic drugs and potentiate their activity. Herein, the ability of non-ionic surfactants (labrasol®, tween 80, cremophore EL and pluronic F127) to form curcumin loaded bicelles with phosphatidylcholine, utilizing a simple method, was investigated. Molecular docking was used to understand the mechanism of bicelles formation. The % transmittance and TEM exhibited bicelles formation with labrasol® and tween 80, while cremophor EL and pluronic F127 tended to form mixed micelles. The surfactant-based nanostructures significantly improved curcumin dissolution (99.2 ± 2.6% within 10 min in case of tween 80-based bicelles) compared to liposomes and curcumin suspension in non-sink conditions. The prepared formulations improved curcumin ex vivo permeation over liposomes and drug suspension. Further, the therapeutic antiviral activity of the formulated curcumin against SARS-CoV-2 was potentiated over drug suspension. Although both Labrasol® and tween 80 bicelles could form bicelles and enhance the oral delivery of curcumin when compared to liposomes and drug suspension, the mixed micelles formulations depicted superiority than bicelles formulations. Our findings provide promising formulations that can be utilized for further preclinical and clinical studies of curcumin as an antiviral therapy for COVID-19 patients. Graphical Abstract.

Nano-lipidic formulation and therapeutic strategies for Alzheimer's disease via intranasal route

AIM

The inability of drug molecules to cross the 'Blood-Brain Barrier' restrict the effective treatment of Alzheimer's disease. Lipid nanocarriers have proven to be a novel paradigm in brain targeting of bioactive by facilitating suitable therapeutic concentrations to be attained in the brain.

METHODS

The relevant information regarding the title of this review article was collected from the peer-reviewed published articles. Also, the physicochemical properties, and their in vitro and in vivo evaluations were presented in this review article.

RESULTS

Administration of lipid-based nano-carriers have abilities to target the brain, improve the pharmacokinetic and pharmacodynamics properties of drugs, and mitigate the side effects of encapsulated therapeutic active agents.

CONCLUSION

Unlike oral and other routes, the Intranasal route promises high bioavailability, low first-pass effect, better pharmacokinetic properties, bypass of the systemic circulation, fewer incidences of unwanted side effects, and direct delivery of anti-AD drugs to the brain via circumventing 'Blood-Brain Barrier'.

Recent advances in drug delivery applications of cubosomes, hexosomes, and solid lipid nanoparticles

The use of lipid nanocarriers for drug delivery applications is an active research area, and a great interest has particularly been shown in the past two decades. Among different lipid nanocarriers, ISAsomes (Internally self-assembled somes or particles), including cubosomes and hexosomes, and solid lipid nanoparticles (SLNs) have unique structural features, making them attractive as nanocarriers for drug delivery. In this contribution, we focus exclusively on recent advances in formation and characterization of ISAsomes, mainly cubosomes and hexosomes, and their use as versatile nanocarriers for different drug delivery applications. Additionally, the advantages of SLNs and their application in oral and pulmonary drug delivery are discussed with focus on the biological fates of these lipid nanocarriers in vivo. Despite the demonstrated advantages in in vitro and in vivo evaluations including preclinical studies, further investigations on improved understanding of the interactions of these nanoparticles with biological fluids and tissues of the target sites is necessary for efficient designing of drug nanocarriers and exploring potential clinical applications.

Crown Ether Nanovesicles (Crownsomes) Repositioned Phenytoin for Healing of Corneal Ulcers

Drug repositioning is an important drug development strategy as it saves the time and efforts exerted in drug discovery. Since reepithelization of the cornea is a critical problem, we envisioned that the anticonvulsant phenytoin sodium can promote reepithelization of corneal ulcers as it was repurposed for skin wound healing. Herein, our aim is to develop novel crown ether-based nanovesicles "Crownsomes" of phenytoin sodium for ocular delivery with minimal drug-induced irritation and enhanced efficacy owing to "host-guest" properties of crown ethers. Crownsomes were successfully fabricated using span-60 and 18-crown-6 and their size, morphology, polydispersity index, ζ potential, drug loading efficiency, conductivity, and drug release were characterized. Crownsomes exhibited favorable properties such as formation of spherical nanovesicles of 280 ± 18 nm and -26.10 ± 1.21 mV surface charges. Crownsomes depicted a high entrapment efficiency (77 ± 5%) with enhanced and controlled-release pattern of phenytoin sodium. The optimum crownsomes formulation ameliorated ex vivo corneal drug permeability (1.78-fold than drug suspension) through the corneal calcium extraction ability of 18-crown-6. In vivo study was conducted utilizing an alkali-induced corneal injury rabbit model. Clinical and histopathological examination confirmed that crownsomes exhibited better biocompatibility and minimal irritation due to complex formation and drug shielding. Further, they enhanced corneal healing, indicating their effectiveness as a novel drug delivery system for ocular diseases.

Biodegradable self-assembled nanoparticles of PEG-PLGA amphiphilic diblock copolymer as a promising stealth system for augmented vinpocetine brain delivery

Vinpocetine (VNP), a semisynthetic drug, is utilized for the treatment of cerebrovascular and memory disorders. This work aimed at formulation of biodegradable VNP long-circulating nanoparticles utilizing Polyethylene glycol methyl ether-block-poly lactide-co-glycolide (PEG-PLGA) copolymer to surmount the drug drawbacks including low oral bioavailability and short elimination half-life. VNP nanoparticles were formulated using nanoprecipitation technique. A 2⁴ factorial design was applied to assess the impact of formulation and process variables on the nanoparticles' characteristics. Statistical analysis revealed that nanoparticles size (Y₁) significantly increased with increasing PEG-PLGA amount (X₁), poly-vinyl alcohol concentration (X₂), and PLGA content (X₄), while decreased with increasing sonication time (X₃). Furthermore, the entrapment efficiency (Y₂) was positively affected by both PEG-PLGA amount and PLGA content, while negatively affected by poly-vinyl alcohol concentration. The optimized formulation prepared using 200 mg of PEG-PLGA polymer (PEG: PLGA 2000: 4,500), 0.5% polyvinyl alcohol with sonication time of 60 s achieved spherical shape with particle size of 43 nm and drug entrapment of 82%. A significant bioavailability enhancement of VNP with marked prolongation of the in vivo systemic exposure of the drug and increased brain levels has also been achieved following intraperitoneal administration in Wistar rats. Thus, the optimized formulation could be regarded as a promising stealth nanocarrier that could surmount the drug pitfalls and enhance its brain delivery.