Formulation, Characterization, and Cytotoxicity Evaluation of Lactoferrin Functionalized Lipid Nanoparticles for Riluzole Delivery to the Brain

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders: drug stability, targeting efficiency, and safety

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely studied. However, their inability to cross the blood-brain barrier hampers the clinical translation of these therapeutic strategies. Liposomes are nanoparticles composed of lipid bilayers, which can effectively encapsulate drugs and improve drug delivery across the blood-brain barrier and into brain tissue through their targeting and permeability. Therefore, they can potentially treat traumatic and nontraumatic central nervous system diseases. In this review, we outlined the common properties and preparation methods of liposomes, including thin-film hydration, reverse-phase evaporation, solvent injection techniques, detergent removal methods, and microfluidics techniques. Afterwards, we comprehensively discussed the current applications of liposomes in central nervous system diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, traumatic brain injury, spinal cord injury, and brain tumors. Most studies related to liposomes are still in the laboratory stage and have not yet entered clinical trials. Additionally, their application as drug delivery systems in clinical practice faces challenges such as drug stability, targeting efficiency, and safety. Therefore, we proposed development strategies related to liposomes to further promote their development in neurological disease research.

Lactoferrin-modified PLGA nanoparticles for pregabalin: development, characterization, in vitro targeting and pharmacodynamic evaluation

Over the years the intranasal drug delivery route has emerged as an effective strategy for drug delivery in the brain. The present study reports the development of Pregabalin-loaded nanoparticles of Poly lactic-co-glycolic acid, surface modified with lactoferrin for targeting brain cells. Lactoferrin was conjugated using Cyanamide 1-Ethyl-3-3-dimethyl aminopropyl carbodiimide and N-hydroxy Succinimide. The physicochemical properties of the nanoparticles were examined and the results showed a particle size of 152.1 ± 1.3 nm, Polydispersity Index 0.146, and surface charge of -17.9 ± 0.98 mV. In vitro, release data in Phosphate Buffer Saline (pH 7.4) and Simulated Nasal Fluid (pH 5.5) suggested that the nanoparticles showed sustained release of the drug (86.92 ± 1.4%) for 48 h. In vitro, cytotoxicity on (RPMI 2650 and Neuro-2a cells) and histopathological evaluation on goat nasal mucosa showed that the formulation was nontoxic. Results from flow cytometry and confocal microscopy confirmed that the cells readily took up modified nanoparticles compared to plain PLGA nanoparticles. The neuroprotective effect of Lf-PLGA nanoparticles was evaluated in Neuro-2a cells concerning Nitric oxide generation in response to lipopolysaccharide. Pharmacodynamic analysis on mice showed enhanced targeting of the drug and the average time of different phases of convulsion was also reduced.

Synthesis and characterization of protein nanohybrid systems for the brain delivery of Riluzole

AIMS

Synthesis and Characterization of Protein NanoHybrid Systems for the Brain Delivery of Riluzole.

METHODS/MATERIALS

Fullerene is converted into carboxylated fullerene (CF) and then, prepared RZU-loaded BSA nanoparticles conjugated with CF.

RESULTS

The particle size and zeta potential of RZU-PNH were found to be 210 ± 1.15 nm and -18.5 ± 0.615 mV respectively, and entrapment efficiency and loading efficiency of RZU-PNH were found to be 98.8 ± 0.53% and 11.6 ± 0.43%, respectively. The XRD of the RZU-PNH shows the amorphism behavior and CD revealed that secondary structure of the protein mainly consists of α-helix andβ-sheet. The MTT assay showed 88.60% and 90.84% cell viability in both SH-SY5Yand N2a cell lines at a concentration of 20 μg/ml and also, no significant nasal ciliotoxicity was observed after incubation with RZU-PNH.

CONCLUSIONS

Obtained results indicated RZU-PNH formulation to treat amyotrophic lateral sclerosis.

In Vitro Evaluation of the Safety and Antineoplastic Effects in Gastrointestinal Tumors of Nanostructured Lipid Carriers Loaded with Berberine

Background/Objectives: Natural substances have been a widely studied source of both pharmaceutical excipients and drugs. Berberine (BRB) is a benzylisoquinoline alkaloid isolated from different plant sources. It possesses various pharmacological properties including antibacterial, antitumor, antidiabetic, neuroprotective, hepatoprotective, anti-inflammatory, antioxidant, etc. However, the limited aqueous solubility hinders its application. Nanosized drug delivery systems are an innovative approach for addressing various challenges regarding drug delivery via different routes of administration. Their utilization could improve the solubility of active constituents. Methods: A melt-emulsification and ultrasonication technique was applied for the preparation of nanostructured lipid carriers (NLCs). They were thoroughly physicochemically characterized by the means of Dynamic Light Scattering, TEM, FTIR, DSC, TGA, and In Vitro release. The In Vitro efficacy and safety were evaluated on cholangiocarcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, lymphoma, fibroblast, and cardioblast cells, as well as rat liver microsomes by means of cytotoxicity assays and the comet assay. Results: The obtained nanoparticles had a spherical shape and size around 158.2 ± 1.8 nm with negative zeta potential. They revealed successful drug loading and improved dissolution of berberine in physiological conditions. The In Vitro safety studies showed that loading BRB in NLCs resulted in improved or retained cytotoxicity to tumor cell lines and reduced cytotoxicity to normal cell lines and liver microsomes. The NLC itself increased microsomal malondialdehyde (MDA) and comet formation. Conclusions: A successful preparation of NLCs with berberine is presented. The nanocarriers show favorable physicochemical and biopharmaceutical properties. The cellular experiments show that the NLC loading of berberine could improve its anticancer efficacy and safety. These findings highlight the potential applicability of berberine in gastrointestinal neoplasms and build the foundation for future practical translation.

Optimization and preparation of doxycycline-loaded chitosan nanoparticles using Box-Behnken design for better diabetic wound healing

A diabetic wound is one of the most devastating difficulties associated with diabetes and leads to significant death and morbidity. Hence, the aim was to make Doxycycline-loaded chitosan nanoparticles (DOX-CNPs) using ionic gelation with a cross-linking technique. In the Box-Behnken design, the DOX-CNPs were optimized by considering the effects of the following 3 variables independently, namely chitosan, sodium tripolyphosphate in volume ratio, strength of chitosan and sodium tripolyphosphate, among several response variables related to nanoparticle properties. The Fourier transform infrared, transmission electron microscopy, differential scanning calorimeter, X-ray diffraction, particle size, entrapment efficiency, and drug release in-vitro were used to characterized the nanoparticles. Additionally, DPPH scavenging activity and activity against Escherichia coli and Staphylococcus aureus bacteria and in vivo characterization were carried out to optimize DOX-CNPs. Then effective delivery of DOX-CNPs is incorporated in chitosan hydrogel for diabetic wounds. The findings of this study indicate that DOX-CNPs exhibit free radical scavenging properties, demonstrate significant antibacterial activity, and enhance cell viability and migration in an in vitro wound healing assay using the L929 fibroblast cell line, and in vivo demonstrate increased blood vessels, collagen deposition epithelization. Chitosan could be used as a drug carrier in a DOX-chitosan-NP system to help develop procedures that can be used in the lab and to treat diabetic wounds.

Bromocriptine mesylate-loaded nanoparticles co-modified with low molecular weight protamine and lactoferrin for enhanced nose-to-brain delivery in Parkinson's disease treatment

Parkinson's disease confronts challenges in drug delivery due to the blood-brain barrier. Intranasal delivery bypasses the blood-brain barrier for improved drug bioavailability, yet narrow nasal space and brief retention time hinder clinical applicability. We conducted a Bromocriptine Mesylate-loaded PLGA nanoparticles co-modified with low molecular weight protamine (LMWP) and lactoferrin (Lf) (LMWP/Lf-BCM-NPs) for nose-to-brain delivery. The resulting LMWP/Lf-BCM-NPs were uniform spheres with an average size of 248.53 ± 16.25 nm and zeta potential of -2.63 ± 0.74 mV. Fourier transform infrared spectroscopy confirmed LMWP and Lf attachment. The co-modified nanoparticles showed improving cellular transport and good viability. The LMWP/Lf-BCM-NPs showed increased brain targeting efficiency in mice. In haloperidol-induced Parkinson mouse models, the LMWP/Lf-BCM-NPs showed increased brain targeting efficiency, enhanced behavioral regulatory effects, enhanced antioxidant effects and neuroprotection effects. This study paves the way for a novel, non-invasive brain-targeted therapy, offering a promising avenue for Parkinson's disease clinical treatment.

A comprehensive review of research advances in the study of lactoferrin to treat viral infections

Lactoferrin (Lf) is a naturally occurring glycoprotein known for its antiviral and antibacterial properties and is present in various physiological fluids. Numerous studies have demonstrated its antiviral effectiveness against multiple viruses, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus (IFV), herpes simplex virus (HSV), hepatitis B virus (HBV), and human immunodeficiency virus (HIV). Lf, a vital component of the mucosal defense system, plays a crucial role in inhibiting viral infection by binding to both host cells and viral particles, such as the Hepatitis C virus (HCV). This interaction enables Lf to keep viral particles away from their target cells, emphasizing its significance as a fundamental element of mucosal defense against viral infections. Additionally, Lf has the ability to modulate cytokine expression and enhance cellular immune responses. In the innate immune system, Lf serves as a unique iron transporter and helps suppress various pathogens like bacteria, fungi, and viruses. This article summarises the potential antiviral properties of Lf against various viruses, along with its other mentioned functions. The advancement of Lf-based therapies supports the homology of food and medicine, providing a promising avenue to address viral infections and other public health challenges.

Nanostructured lipid carriers for enhanced batimastat delivery across the blood-brain barrier: an in vitro study for glioblastoma treatment

Glioblastoma presents a significant treatment challenge due to the blood-brain barrier (BBB) hindering drug delivery, and the overexpression of matrix metalloproteinases (MMPs), which promotes tumor invasiveness. This study introduces a novel nanostructured lipid carrier (NLC) system designed for the delivery of batimastat, an MMP inhibitor, across the BBB and into the glioblastoma microenvironment. The NLCs were functionalized with epidermal growth factor (EGF) and a transferrin receptor-targeting construct to enhance BBB penetration and entrapment within the tumor microenvironment. NLCs were prepared by ultrasonicator-assisted hot homogenization, followed by surface functionalization with EGF and the construct though carbodiimide chemistry. The construct was successfully conjugated with an efficiency of 81%. Two functionalized NLC formulations, fMbat and fNbat, differing in the surfactant amount, were characterized. fMbat had a size of 302 nm, a polydispersity index (PDI) of 0.298, a ζ-potential (ZP) of -27.1 mV and an 85% functionalization efficiency (%FE), whereas fNbat measured 285 nm, with a PDI of 0.249, a ZP of -28.6 mV and a %FE of 92%. Both formulations achieved a drug loading of 0.42 μg/mg. In vitro assays showed that fNbat was cytotoxic and failed to cross the BBB, while fMbat showed cytocompatibility at concentrations 10 times higher than the drug's IC50. Additionally, fMbat inhibited MMP-2 activity between 11 and 62% across different cell lines and achieved a three-fold increase in BBB penetration upon functionalization. Our results suggest that the fMbat formulation has potential for enhancing GB treatment by overcoming current drug delivery limitations and may be combined with other therapeutic strategies for improved outcomes.

Modulation of IFN-γ induced macrophage inflammatory responses via indomethacin-loaded NLCs for OA management

Macrophages are the main cells present in the synovial membrane. They play an important role in the development and progression of osteoarthritis (OA). After the establishment of the disease macrophages mostly adopt a pro-inflammatory secretory phenotype (OA phenotype) further inducing cartilage degradation. Indomethacin (IND) is a non-steroidal anti-inflammatory drug (NSAID) able to inhibit the synthesis of prostaglandins mediated by both cyclooxygenase isoforms depicting a potent anti-inflammatory capacity. However, the lack of specificity and short half-like of free drugs within the joint cavity limits its utility in controlling inflammation after intra-articular administration. This study aims at developing IND loaded glycosylated nanostructured lipid carriers (NLCs) to selectively target macrophages and promote their reprogramming to an anti-inflammatory phenotype. This approach focused on the local administration of the NLCs, offers a promising therapeutic strategy for treating OA by modulating the inflammatory environment within the joint. NLCs will be designed by combining experimental and in silico docking analyses, and thoroughly characterized to obtain drug delivery systems with high stability and suitable physicochemical properties. The proposed mannose-functionalized systems exhibited adequate particle sizes (≈ 70 nm) and positive surface charges (> 20 mV) to be efficiently retained in the joint cavity. Moreover, the developed NLCs demonstrated effective and specific uptake by OA-like macrophages leading to a significant decrease in the secretion of the pro-inflammatory cytokines IL-6, IL-8 and TNF-α similarly to the free drug. Therefore, these systems effectively reprogrammed OA-associated macrophages to adopt a more regenerative phenotype, offering a promising strategy for managing inflammation in OA.

Navigating Neurotoxicity and Safety Assessment of Nanocarriers for Brain Delivery: Strategies and Insights

Nanomedicine, an area that uses nanomaterials for theragnostic purposes, is advancing rapidly, particularly in the detection and treatment of neurodegenerative diseases. The design of nanocarriers can be optimized to enhance drug bioavailability and targeting to specific organs, improving therapeutic outcomes. However, clinical translation hinges on biocompatibility and safety. Nanocarriers can cross the blood-brain barrier (BBB), potentially causing neurotoxic effects through mechanisms such as oxidative stress, DNA damage, and neuroinflammation. Concerns about their accumulation and persistence in the brain make it imperative to carry out a nanotoxicological risk assessment. Generally, this involves identifying exposure sources and routes, characterizing physicochemical properties, and conducting cytotoxicity assays both in vitro and in vivo. The lack of a specialized regulatory framework creates substantial gaps, making it challenging to translate findings across development stages. Additionally, there is a pressing need for innovative testing methods due to constraints on animal use and the demand for high-throughput screening. This review examines the mechanisms of nanocarrier-induced neurotoxicity and the challenges in risk assessment, highlighting the impact of physicochemical properties and the advantages and limitations of current neurotoxicity evaluation models. Future perspectives are also discussed. Additional guidance is crucial to improve the safety of nanomaterials and reduce associated uncertainty. STATEMENT OF SIGNIFICANCE: Nanocarriers show tremendous potential for theragnostic purposes in neurological diseases, enhancing drug targeting to the brain, and improving biodistribution and pharmacokinetics. However, their neurotoxicity is still a major field to be explored, with only 5% of nanotechnology-related publications addressing this matter. This review focuses on the issue of neurotoxicity and safety assessment of nanocarriers for brain delivery. Neurotoxicity-relevant exposure sources, routes, and molecular mechanisms, along with the impact of the physicochemical properties of nanomaterials, are comprehensively described. Moreover, the different experimental models used for neurotoxicity evaluation are explored at length, including their main advantages and limitations. To conclude, we discuss current challenges and future perspectives for a better understanding of risk assessment of nanocarriers for neurobiomedical applications.

A Comprehensive Review of Nanoparticles: From Classification to Application and Toxicity

Nanoparticles are structures that possess unique properties with high surface area-to-volume ratio. Their small size, up to 100 nm, and potential for surface modifications have enabled their use in a wide range of applications. Various factors influence the properties and applications of NPs, including the synthesis method and physical attributes such as size and shape. Additionally, the materials used in the synthesis of NPs are primary determinants of their application. Based on the chosen material, NPs are generally classified into three categories: organic, inorganic, and carbon-based. These categories include a variety of materials, such as proteins, polymers, metal ions, lipids and derivatives, magnetic minerals, and so on. Each material possesses unique attributes that influence the activity and application of the NPs. Consequently, certain NPs are typically used in particular areas because they possess higher efficiency along with tenable toxicity. Therefore, the classification and the base material in the NP synthesis hold significant importance in both NP research and application. In this paper, we discuss these classifications, exemplify most of the major materials, and categorize them according to their preferred area of application. This review provides an overall review of the materials, including their application, and toxicity.

Functional Polyphenol-Based Nanoparticles Boosted the Neuroprotective Effect of Riluzole for Acute Spinal Cord Injury

Riluzole is commonly used as a neuroprotective agent for treating traumatic spinal cord injury (SCI), which works by blocking the influx of sodium and calcium ions and reducing glutamate activity. However, its clinical application is limited because of its poor solubility, short half-life, potential organ toxicity, and insufficient bioabilities toward upregulated inflammation and oxidative stress levels. To address this issue, epigallocatechin gallate (EGCG), a natural polyphenol, was employed to fabricate nanoparticles (NPs) with riluzole to enhance the neuroprotective effects. The resulting NPs demonstrated good biocompatibility, excellent antioxidative properties, and promising regulation effects from the M1 to M2 macrophages. Furthermore, an in vivo SCI model was successfully established, and NPs could be obviously aggregated at the SCI site. More interestingly, excellent neuroprotective properties of NPs through regulating the levels of oxidative stress, inflammation, and ion channels could be fully demonstrated in vivo by RNA sequencing and sophisticated biochemistry evaluations. Together, the work provided new opportunities toward the design and fabrication of robust and multifunctional NPs for oxidative stress and inflammation-related diseases via biological integration of natural polyphenols and small-molecule drugs.

Polymersomes for Sustained Delivery of a Chalcone Derivative Targeting Glioblastoma Cells

Glioblastoma (GBM) is a primary malignant tumor of the central nervous system responsible for the most deaths among patients with primary brain tumors. Current therapies for GBM are not effective, with the average survival of GBM patients after diagnosis being limited to a few months. Chemotherapy is difficult in this case due to the heterogeneity of GBM and the high efficacy of the blood-brain barrier, which makes drug absorption into the brain extremely difficult. In a previous study, 3',4',3,4,5-trimethoxychalcone (MB) showed antiproliferative and anti-invasion activities toward GBM cells. Polymersomes (PMs) are an attractive, new type of nanoparticle for drug administration, due to their high stability, enhanced circulation time, biodegradability, and sustained drug release. In the present study, different MB formulations, PEG2000-PCL and PEG5000-PCL, were synthesized, characterized, and compared in terms of 14-day stability and in vitro cytotoxicity (hCMEC/D3 and U-373 MG).

Crisaborole-Enthused Glycerosomal Gel for an Augmented Skin Permeation

BACKGROUND

Crisaborole (CB), a boron-based compound, is the first topical PDE4 inhibitor to be approved by the US Food and Drug Administration (2016) for the treatment of Atopic Dermatitis. It is marketed as a 2% ointment (Eucrisa, Pfizer). However, CB is insoluble in water; therfore, CB glycersomes were formulated to enhance its permeation flux across the skin.

OBJECTIVE

We developed a glycerosomal gel of CB and compared its in vitro release and permeation flux with the 2% conventional ointment.

METHODS

Glycerosomes were prepared using thin film hydration method employing CB, soya phosphatidylcholine, and cholesterol. The formed film was further hydrated employing a mixture of phosphate buffer pH 7.4 /glycerin solution containing varying percentages (20,30, 40, and 50 %) of glycerol. The glycerosomes obtained were characterized by their size, polydispersity index (PDI), and Zeta potential. The entrapment efficiency of the optimized formulation (F1) was determined. The in vitro release of F1 was compared with its 2% conventional ointment. F1 was further incorporated into carbopol 934 P gel. The gel was characterized by pH, viscosity, spreadability, and drug content. The permeability flux of the glycerosomal gel was compared with its 2% conventional ointment.

RESULTS

The optimized CB glycerosomes had a vesicle size of 137.5 ± 50.58 nm, PDI 0.342, and zeta potential -65.4 ± 6.75 mV. CB glycerosomal gel demonstrated a 2.13-fold enhancement in the permeation flux.

CONCLUSION

It can thereby be concluded that glycerosomes can be an effective delivery system to enhance the penetration of CB across the skin.

Preparation and characterization of brain-targeted polymeric nanocarriers (Frankincense-PMBN-lactoferrin) and in-vivo evaluation on an Alzheimer's disease-like rat model induced by scopolamine

Experiments have demonstrated that frankincense may offer protection against scopolamine-induced Alzheimer's disease by mitigating cholinergic dysfunction and inhibiting inflammatory mediators. Nevertheless, its instability and limited water solubility lead to diminished medicinal efficacy. In this study, we utilized PMBN (poly [MPC-co-(BMA)-co-(MEONP)]) as a nanocarrier for targeted brain drug delivery of frankincense, employing lactoferrin as a ligand for precise targeting. Characterization of nanoparticle properties was conducted through FTIR and FESEM analysis, and the in-vitro drug release percentage from the nanoparticles was quantified. To induce Alzheimer's-like dementia in rats, scopolamine was intraperitoneally administered at a dose of 1 mg/kg/day for 14 days. Subsequently, behavioral assessments (Y-maze, passive avoidance test, tail suspension test) were performed, followed by evaluations of acetylcholinesterase (AChE), reduced glutathione (GSH), catalase (CAT), and brain histopathology at the conclusion of the treatment period. The results revealed that the nanoparticles had a size of 106.6 nm and a zeta potential of -3.8 mV. The maximum release of frankincense in the PBS environment from PMBN nanoparticles was 18.2 %, in accordance with the Peppas model. Behavioral tests indicated that targeted drug nanoparticles (F-PMBN-Lf) exhibited the capability to alleviate stress and depression while enhancing short-term memory in scopolamine-induced animals. Additionally, F-PMBN-Lf counteracted the scopolamine-induced elevation of AChE activity and GSH levels. However, it resulted in decreased activity of the antioxidant enzyme CAT compared to the scopolamine group. Histological analysis of brain tissue suggested that F-PMBN-Lf exerted a notable neuroprotective effect, preserving neuronal cells in contrast to the scopolamine-induced group. It appears that the polymer nanoparticles containing this plant extract have introduced a novel neuroprotective approach for the treatment of Alzheimer's disease.

Nose to Brain Delivery of Transferrin conjugated PLGA nanoparticles for clonidine

The present work focuses on the development of surface modified transferrin PLGA nanoparticles loaded with clonidine for nose to brain delivery. The CLD-Tf-PLGA-NPs were developed using double emulsification, followed by solvent evaporation and characterization. Particle size, PDI and Zeta potential of the nanoparticles was 199.5 ± 1.36 nm, 0.291, -17.4 ± 6.29 mV respectively with EE% 86.2 ± 2.12 %, and DL%, 7.8 ± 0.48 %. TEM, SEM and FTIR analysis were carried out to confirm the size and transferrin coating over the surface of nanoparticles. In-vitro drug release profile were studied in PBS (pH 7.4) and SNF (pH 5.5) for 72 h and highest release was observed in PBS 89.54 ± 3.17 %. Cellular assays were conducted on Neuro-2a cells to check the cytotoxicity and uptake of Tf-modified PLGA nanoparticles and the cell viability% was obtained to be 61.85 ± 4.48 % even at maximum concentration (40Cmax) with uptake of approximately 97 %. Histopathological studies were also performed to identify the cytotoxicity on nasal epithelium along with in-vivo biodistribution and pharmacodynamics studies to assess the concentration of drug in the mice brain and behavioural responses after intranasal delivery of surface modified nanoparticles. The results showed significant increase in concentration of drug in brain and behavioural improvements in mice (p < 0.05).

Nanovesicular-Mediated Intranasal Drug Therapy for Neurodegenerative Disease

Numerous neurodegenerative conditions, such as Alzheimer's, Huntington's, Parkinson's, amyotrophic lateral sclerosis, and glioblastoma multiform are now becoming significant concerns of global health. Formulation-related issues, physiological and anatomical barriers, post-administration obstacles, physical challenges, regulatory limitations, environmental hurdles, and health and safety issues have all hindered successful delivery and effective outcomes despite a variety of treatment options. In the current review, we covered the intranasal route, an alternative strategic route targeting brain for improved delivery across the BBB. The trans-nasal pathway is non-invasive, directing therapeutics directly towards brain, circumventing the barrier and reducing peripheral exposure. The delivery of nanosized vesicles loaded with drugs was also covered in the review. Nanovesicle systems are organised in concentric bilayered lipid membranes separated with aqueous layers. These carriers surmount the disadvantages posed by intranasal delivery of rapid mucociliary clearance and enzymatic degradation, and enhance retention of drug to reach the site of target. In conclusion, the review covers in-depth conclusions on numerous aspects of formulation of drug-loaded vesicular system delivery across BBB, current marketed nasal devices, significant jeopardies, potential therapeutic aids, and current advancements followed by future perspectives.

The battle of lipid-based nanocarriers against blood-brain barrier: a critical review

Central nervous system integrity is the state of brain functioning across sensory, cognitive, emotional-social behaviors, and motor domains, allowing a person to realise his full potential. Thus, brain disorders seriously affect patients' quality of life. Efficient drug delivery to treat brain disorders remains a crucial challenge due to numerous brain barriers, particularly the blood-brain barrier (BBB), which greatly impacts the ultimate drug therapeutic efficacy. Lately, nanocarrier technology has made huge progress in overcoming these barriers by improving drug solubility, ameliorating its retention, reducing its toxicity, and targeting the encapsulated agents to different brain tissues. The current review primarily offers an overview of the different components of BBB and the progress, strategies, and contemporary applications of the nanocarriers, specifically lipid-based nanocarriers (LBNs), in treating various brain disorders.

Nanostructured Lipid Carriers Enriched Hydrogels for Skin Topical Administration of Quercetin and Omega-3 Fatty Acid

Chronic skin exposure to external hostile agents (e.g., UV radiation, microorganisms, and oxidizing chemicals) may increase oxidative stress, causing skin damage and aging. Because of their well-known skincare and protective benefits, quercetin (Q) and omega-3 fatty acids (ω3) have attracted the attention of the dermocosmetic and pharmaceutical sectors. However, both bioactives have inherent properties that limit their efficient skin delivery. Therefore, nanostructured lipid carriers (NLCs) and enriched PFC® hydrogels (HGs) have been developed as a dual-approach vehicle for Q and/or ω3 skin topical administration to improve bioactives' stability and skin permeation. Two NLC formulations were prepared with the same lipid composition but differing in surfactant composition (NLC1-soy lecithin and poloxamer 407; NLC2-Tween® 80 and dioctyl sodium sulfosuccinate (DOSS)), which have an impact on physicochemical properties and pharmaceutical and therapeutic performance. Despite both NLCs presenting high Q loading capacity, NLC2's physicochemical properties make them more suitable for topical skin administration and ensure longer colloidal stability. Additionally, NLC2 demonstrated a more sustained Q release, indicating higher bioactive storage while improving permeability. The occlusive effect of NLCs-enriched HGs also has a positive impact on skin permeability. Q-loaded NLC2, with or without ω3, -enriched HGs demonstrated efficacy as antioxidant and photoprotective formulations as well as effective reduction in S. aureus growth, indicating that they constitute a promising approach for topical skin administration to prevent skin aging and other damaging cutaneous processes.

Recent Advancements in Nanomaterials: A Promising Way to Manage Neurodegenerative Disorders

Neurodegenerative diseases (NDs) such as dementia, Alzheimer's disease, Parkinson's disease, frontotemporal dementia, and amyotrophic lateral sclerosis are some of the most prevalent disorders currently afflicting healthcare systems. Many of these diseases share similar pathological hallmarks, including elevated oxidative stress, mitochondrial dysfunction, protein misfolding, excitotoxicity, and neuroinflammation, all of which contribute to the deterioration of the nervous system's structure and function. The development of diagnostic and therapeutic materials in the monitoring and treatment of these diseases remains challenging. One of the biggest challenges facing therapeutic and diagnostic materials is the blood-brain barrier (BBB). The BBB is a multifunctional membrane possessing a plethora of biochemical, cellular, and immunological features that ensure brain homeostasis by preventing the entry and accumulation of unwanted compounds. With regards to neurodegenerative diseases, the recent application of tailored nanomaterials (nanocarriers and nanoparticles) has led to advances in diagnostics and therapeutics. In this review, we provide an overview of commonly used nanoparticles and their applications in NDs, which may offer new therapeutic strategies for the prevention and treatment of neurodegenerative diseases.

Nanoparticle-Based Drug Delivery Systems: An Inspiring Therapeutic Strategy for Neurodegenerative Diseases

Neurodegenerative diseases are common, incurable neurological disorders with high prevalence, and lead to memory, movement, language, and intelligence impairments, threatening the lives and health of patients worldwide. The blood-brain barrier (BBB), a physiological barrier between the central nervous system and peripheral blood circulation, plays an important role in maintaining the homeostasis of the intracerebral environment by strictly regulating the transport of substances between the blood and brain. Therefore, it is difficult for therapeutic drugs to penetrate the BBB and reach the brain, and this affects their efficacy. Nanoparticles (NPs) can be used as drug transport carriers and are also known as nanoparticle-based drug delivery systems (NDDSs). These systems not only increase the stability of drugs but also facilitate the crossing of drugs through the BBB and improve their efficacy. In this article, we provided an overview of the types and administration routes of NPs, highlighted the preclinical and clinical studies of NDDSs in neurodegenerative diseases, and summarized the combined therapeutic strategies in the management of neurodegenerative diseases. Finally, the prospects and challenges of NDDSs in recent basic and clinical research were also discussed. Above all, NDDSs provide an inspiring therapeutic strategy for the treatment of neurodegenerative diseases.

Riluzole-Loaded Nanostructured Lipid Carriers for Hyperproliferative Skin Diseases

Nanocarriers, and especially nanostructured lipid carriers (NLC), represent one of the most effective systems for topical drug administration. NLCs are biodegradable, biocompatible and provide a prolonged drug release. The glutamate release inhibitor Riluzole (RLZ) is a drug currently used for amyotrophic lateral sclerosis (ALS), with anti-proliferative effects potentially beneficial for diseases with excessive cell turnover. However, RLZ possesses low water solubility and high light-sensibility. We present here optimized NLCs loaded with RLZ (RLZ-NLCs) as a potential topical treatment. RLZ-NLCs were prepared by the hot-pressure homogenization method using active essential oils as liquid lipids, and optimized using the design of experiments approach. RLZ-NLCs were developed obtaining optimal properties for dermal application (mean size below 200 nm, negative surface charge and high RLZ entrapment efficacy). In vitro release study demonstrates that RLZ-NLCs allow the successful delivery of RLZ in a sustained manner. Moreover, RLZ-NLCs are not angiogenic and are able to inhibit keratinocyte cell proliferation. Hence, a NLCs delivery system loading RLZ in combination with natural essential oils constitutes a promising strategy against keratinocyte hyperproliferative conditions.

Clindamycin phosphate and bone morphogenetic protein-7 loaded combined nanoparticle-graft and nanoparticle-film formulations for alveolar bone regeneration - An in vitro and in vivo evaluation

Commonly utilized techniques for healing alveolar bone destruction such as the use of growth factors, suffering from short half-life, application difficulties, and the ability to achieve bioactivity only in the presence of high doses of growth factor. The sustained release of growth factors through a scaffold-based delivery system offers a promising and innovative tool in dentistry. Furthermore, it is suggested to guide the host response by using antimicrobials together with growth factors to prevent recovery and achieve ideal regeneration. Herein, the aim was to prepare and an in vitro - in vivo evaluation of bone morphogenetic protein 7 (BMP-7) and clindamycin phosphate (CDP) loaded polymeric nanoparticles, and their loading into the alginate-chitosan polyelectrolyte complex film or alloplastic graft to accelerate hard tissue regeneration. PLGA nanoparticles containing CDP and BMP-7, separately or together, were prepared using the double emulsion solvent evaporation technique. Through in vitro assays, it was revealed that spherical particles were homogeneously distributed in the combination formulations, and sustained release could be achieved for >12 weeks with all formulations. Also, results from the micro-CT and histopathological analyses indicated that CDP and BMP-7 loaded nanoparticle-film formulations were more effective in treatment than the nanoparticle loaded grafts.

Potential of Lipid-Based Nanocarriers against Two Major Barriers to Drug Delivery-Skin and Blood-Brain Barrier

Over the past few years, pharmaceutical and biomedical areas have made the most astounding accomplishments in the field of medicine, diagnostics and drug delivery. Nanotechnology-based tools have played a major role in this. The implementation of this multifaceted nanotechnology concept encourages the advancement of innovative strategies and materials for improving patient compliance. The plausible usage of nanotechnology in drug delivery prompts an extension of lipid-based nanocarriers with a special reference to barriers such as the skin and blood-brain barrier (BBB) that have been discussed in the given manuscript. The limited permeability of these two intriguing biological barriers restricts the penetration of active moieties through the skin and brain, resulting in futile outcomes in several related ailments. Lipid-based nanocarriers provide a possible solution to this problem by facilitating the penetration of drugs across these obstacles, which leads to improvements in their effectiveness. A special emphasis in this review is placed on the composition, mechanism of penetration and recent applications of these carriers. It also includes recent research and the latest findings in the form of patents and clinical trials in this field. The presented data demonstrate the capability of these carriers as potential drug delivery systems across the skin (referred to as topical, dermal and transdermal delivery) as well as to the brain, which can be exploited further for the development of safe and efficacious products.

Solid lipid-based nanoparticulate system for sustained release and enhanced in-vitro cytotoxic effect of 5-fluorouracil on skin Melanoma and squamous cell carcinoma

The present study aimed to prepare solid lipid-based nanoparticles (SLNs) using Precirol® ATO 5 as solid lipid and Poloxamer 188 and Tween 80 as surfactant and co-surfactant respectively, and SLNs-derived gel for sustained delivery, enhanced in-vitro cytotoxicity, enhanced cellular uptake of 5-FU and enhanced permeation of 5-FU across the skin. The 5-FU-loaded SLNs were prepared by the hot melt encapsulation method and converted into SLN-derived gel using a gelling agent (Carbopol 940). The 5-FU-loaded SLNs had a particle size in the range of 76.82±1.48 to 327±4.46 nm, zeta potential between -11.3±2.11 and -28.4±2.40 mV, and entrapment efficiency (%) in range of 63.46±1.13 and 76.08±2.42. The FTIR analysis depicted that there was no chemical interaction between 5-FU and formulation components. Differential scanning calorimetric analysis showed thermal stability of 5-FU in the nanoparticles and powdered X-ray diffraction analysis revealed successful incorporation of 5-FU in nanoparticles. The in-vitro release study of 5-FU-loaded SLNs showed biphasic release behavior with initial burst release followed by sustained release over 48 hr. The 5-FU-loaded SLNs showed a greater cytotoxic effect on skin melanoma (B16F10 cells) and squamous cell carcinoma (A-431 cells) as compared to free 5-FU drug solution after 48 hr. Flow cytometry and fluorescence microscopy displayed enhanced quantitative and qualitative cellular uptake of SLNs. The SLNs formulation showed acceptable safety and biocompatible profile after an acute toxicity study in Wistar rats. Moreover, ex-vivo permeation studies depicted 2.13±0.076 folds enhanced flux of 5-FU-loaded SLN derived gel compared to 5-FU plain gel, and skin retention studies revealed target efficiency (%) 2.54±0.03 of 5-FU-loaded SLN derived gel compared to 5-FU plain gel.

Parenteral Lipid-Based Nanoparticles for CNS Disorders: Integrating Various Facets of Preclinical Evaluation towards More Effective Clinical Translation

Contemporary trends in combinatorial chemistry and the design of pharmaceuticals targeting brain disorders have favored the development of drug candidates with increased lipophilicity and poorer water solubility, with the expected improvement in delivery across the blood-brain barrier (BBB). The growing availability of innovative excipients/ligands allowing improved brain targeting and controlled drug release makes the lipid nanocarriers a reasonable choice to overcome the factors impeding drug delivery through the BBB. However, a wide variety of methods, study designs and experimental conditions utilized in the literature hinder their systematic comparison, and thus slows the advances in brain-targeting by lipid-based nanoparticles. This review provides an overview of the methods most commonly utilized during the preclinical testing of liposomes, nanoemulsions, solid lipid nanoparticles and nanostructured lipid carriers intended for the treatment of various CNS disorders via the parenteral route. In order to fully elucidate the structure, stability, safety profiles, biodistribution, metabolism, pharmacokinetics and immunological effects of such lipid-based nanoparticles, a transdisciplinary approach to preclinical characterization is mandatory, covering a comprehensive set of physical, chemical, in vitro and in vivo biological testing.

Nanocarrier-Based Drug Delivery to Brain: Interventions of Surface Modification

Brain disorders are a prevalent and rapidly growing problem in the medical field as they adversely affect the quality of life of a human. With an increase in life expectancy, it has been reported that diseases like Alzheimer's, Parkinson's, stroke and brain tumors, along with neuropsychological disorders, are also being reported at an alarmingly high rate. Despite various therapeutic methods for treating brain disorders, drug delivery to the brain has been challenging because of a very complex Blood Brain Barrier, which precludes most drugs from entering the brain in effective concentrations. Nano-carrier-based drug delivery systems have been reported widely by researchers to overcome this barrier layer. These systems due to their small size, offer numerous advantages; however, their short residence time in the body owing to opsonization hinders their success in vivo. This review article focuses on the various aspects of modifying the surfaces of these nano-carriers with polymers, surfactants, protein, antibodies, cell-penetrating peptides, integrin binding peptides and glycoproteins such as transferrin & lactoferrin leading to enhanced residence time, desirable characteristics such as the ability to cross the blood-brain barrier (BBB), increased bioavailability in regions of the brain and targeted drug delivery.

New insight into brain disease therapy: nanomedicines-crossing blood-brain barrier and extracellular space for drug delivery

INTRODUCTION

Brain diseases including brain tumor, Alzheimer's disease, Parkinson's disease, etc. are difficult to treat. The blood-brain barrier (BBB) is a major obstacle for drug delivery into the brain. Although nano-package and receptor-mediated delivery of nanomedicine markedly increases BBB penetration, it yet did not extensively improve clinical cure rate. Recently, brain extracellular space (ECS) and interstitial fluid (ISF) drainage in ECS have been found to determine whether a drug dissolved in ISF can reach its target cells. Notably, an increase in tortuosity of ECS associated with slower ISF drainage induced by the accumulated harmful substances, such as: amyloid-beta (Aβ), α-synuclein, and metabolic wastes, causes drug delivery failure.

AREAS COVERED

The methods of nano-package and receptor-mediated drug delivery and the penetration efficacy of nanomedicines across BBB and ECS are assessed.

EXPERT OPINION

Invasive delivering drug via ECS and noninvasive near-infrared photo-sensitive nanomedicines may provide a promising benefit to patients with brain disease.

Lipid nanoparticles strategies to modify pharmacokinetics of central nervous system targeting drugs: Crossing or circumventing the blood-brain barrier (BBB) to manage neurological disorders

The main limitation to the success of central nervous system (CNS) therapies lies in the difficulty for drugs to cross the blood-brain barrier (BBB) and reach the brain. Regarding its structure and enzymatic complexity, crossing the BBB is a challenge, although several alternatives have been identified. For instance, the use of drugs encapsulated in lipid nanoparticles has been described as one of the most efficient approaches to bypass the BBB, as they allow the passage of drugs through this barrier, improving brain bioavailability. In particular, solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) have been a focus of research related to drug delivery to the brain. These systems provide protection of lipophilic drugs, improved delivery and bioavailability, having a major impact on treatments outcomes. In addition, the use of lipid nanoparticles administered via routes that transport drugs directly into the brain seems a promising solution to avoid the difficulties in crossing the BBB. For instance, the nose-to-brain route has gained considerable interest, as it has shown efficacy in 3D human nasal models and in animal models. This review addresses the state of the art on the use of lipid nanoparticles to modify the pharmacokinetics of drugs employed in the management of neurological disorders. A description of the structural components of the BBB, the role of the neurovascular unit and limitations for drugs to entry into the CNS is first addressed, along with the developments to increase drug delivery to the brain, with a special focus on lipid nanoparticles. In addition, the obstacle of BBB complexity in the creation of new effective drugs for the treatment of the most prevalent neurological disorders is also addressed. Finally, the proposed strategies for lipid nanoparticles to reach the CNS, crossing or circumventing the BBB, are described. Although promising results have been reported, especially with the nose-to-brain route, they are still ongoing to assess its real efficacy in vivo in the management of neurological disorders.

Research Advances of Lactoferrin in Electrostatic Spinning, Nano Self-Assembly, and Immune and Gut Microbiota Regulation

Lactoferrin (LF) is a naturally present iron-binding globulin with the structural properties of an N-lobe strongly positively charged terminus and a cage-like structure of nano self-assembly encapsulation. These unique structural properties give it potential for development in the fields of electrostatic spinning, targeted delivery systems, and the gut-brain axis. This review will provide an overview of LF's unique structure, encapsulation, and targeted transport capabilities, as well as its applications in immunity and gut microbiota regulation. First, the microstructure of LF is summarized and compared with its homologous ferritin, revealing both structural and functional similarities and differences between them. Second, the electrostatic interactions of LF and its application in electrostatic spinning are summarized. Its positive charge properties can be applied to functional environmental protection packaging materials and to improving drug stability and antiviral effects, while electrostatic spinning can promote bone regeneration and anti-inflammatory effects. Then the nano self-assembly behavior of LF is exploited as a cage-like protein to encapsulate bioactive substances to construct functional targeted delivery systems for applications such as contrast agents, antibacterial dressings, anti-cancer therapy, and gene delivery. In addition, some covalent and noncovalent interactions of LF in the Maillard reaction and protein interactions and other topics are briefly discussed. Finally, LF may affect immunological function via controlling the gut microbiota. In conclusion, this paper reviews the research advances of LF in electrostatic spinning, nano self-assembly, and immune and gut microbiota regulation, aiming to provide a reference for its application in the food and pharmaceutical fields.

Taking Advantages of Blood–Brain or Spinal Cord Barrier Alterations or Restoring Them to Optimize Therapy in ALS?

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder that still lacks an efficient therapy. The barriers between the central nervous system (CNS) and the blood represent a major limiting factor to the development of drugs for CNS diseases, including ALS. Alterations of the blood–brain barrier (BBB) or blood–spinal cord barrier (BSCB) have been reported in this disease but still require further investigations. Interestingly, these alterations might be involved in the complex etiology and pathogenesis of ALS. Moreover, they can have potential consequences on the diffusion of candidate drugs across the brain. The development of techniques to bypass these barriers is continuously evolving and might open the door for personalized medical approaches. Therefore, identifying robust and non-invasive markers of BBB and BSCB alterations can help distinguish different subgroups of patients, such as those in whom barrier disruption can negatively affect the delivery of drugs to their CNS targets. The restoration of CNS barriers using innovative therapies could consequently present the advantage of both alleviating the disease progression and optimizing the safety and efficiency of ALS-specific therapies.