Development of Microneedle Patch Loaded with Bacopa monnieri Solid Lipid Nanoparticles for the Effective Management of Parkinson's Disease

Microneedle-mediated drug delivery for neurological diseases

Neurological disorders, including brain injury, brain tumors, and neurodegenerative diseases, rank as the second leading cause of death worldwide. Exploring effective new treatments for neurological disorders has long been a hot research issue in clinical practice. Recently, microneedles (MNs) have attracted much attention due to their designation as a "painless and non-invasive" novel transdermal delivery method, characterized by their biocompatibility and sustainability. The advantages of MNs open an avenue for potential therapeutic interventions targeting neurological disorders. This review presents a concise overview of progress in the field of MNs, with highlights on the application in the treatment of neurological disorders. Notably, trends in the development of MNs and future challenges are also discussed.

Enhancing selegiline hydrochloride efficacy: Box Behnken-optimized liposomal delivery via intranasal route for Parkinson's disease intervention

The clinical use of selegiline hydrochloride in conventional dosage forms is to reduce the progression of Parkinson's disease (PD). However, its limited access to the brain, short half-life, and first-pass metabolism minimize brain uptake. Nano-based liposomes offer promising tools for brain-targeted delivery of therapeutics, especially intranasally administered cationic liposomes that target the brain region via the olfactory route and reduce biodistribution. In the present work, cationic liposomes encapsulated with selegiline hydrochloride were fabricated for intranasal administration against PD. The liposomes were initially optimized by Box Behnken design, and the selected run was coated with stearylamine to provide a cationic charge to the liposomes. The final coated liposomes, SH-LP3, demonstrated a minimum size of 173 ± 2.13 nm, an ideal zeta potential of +16 ± 1.98, and achieved a maximum entrapment efficiency of 40.14 ± 1.83%. Morphology analysis showed the spherical shape of liposomes in the size range of 100-200 nm. The in vitro cytotoxicity assay in SHSY5Y cell lines showed a significant decrease in toxicity, almost ten times less, compared to pure selegiline hydrochloride. Animal studies on rotenone-lesioned C57BL6 mice model for PD were performed to investigate the effect of intranasally administered liposomes. The SH-LP3 formulation exhibited remarkable effectiveness in relieving symptoms of PD. This extensive analysis emphasizes the possibility of intranasally administered SH-LP3 liposomes as a feasible treatment option for PD. The formulation not only delivers continuous drug release but also displays better safety and efficacy, providing a platform for additional studies and growth in the domain of PD treatment.

Overcoming challenges in dermal and transdermal delivery of herbal therapeutics with polymeric microneedles

Natural products are generally preferred medications owing to their low toxicity and irritancy potential. However, a good number of herbal therapeutics (HT) exhibit solubility, permeability and stability issues that eventually affect oral bioavailability. Transdermal administration has been successful in resolving some of these issues which has lead in commercialization of a few herbal transdermal products. Polymeric Microneedles (MNs) has emerged as a promising platform in transdermal delivery of HT that face problems in permeating the skin. Several biocompatible and biodegradable polymers used in the fabrication of MNs have been discussed. MNs have been exploited for cutaneous delivery of HT in management of skin ailments like skin cancer, acne, chronic wounds and hypertrophic scar. Considering the clinical need, MNs are explored for systemic delivery of potent HT for management of diverse disorders like asthma, disorders of central nervous system and nicotine replacement as it obviates first pass metabolism and elicits a quicker onset of therapeutic response. MNs of HT have found good number of aesthetic applications in topical delivery of HT to the skin. Interestingly, MNs have emerged as an attractive option as a minimally invasive diagnostic aid in sampling biomarkers from plants, skin and ocular interstitial fluid. The review updates the progress made by MN technology of HT for multiple therapeutic interventions along with the future challenges. An attempt is made to illustrate the challenging formulation strategies employed in the fabrication of polymeric MNs of HT. Efforts are on to extend the potential applications of polymeric MNs to HT for diverse therapeutic applications.

Retracted: Development of Microneedle Patch Loaded with Bacopa monnieri Solid Lipid Nanoparticles for the Effective Management of Parkinson's Disease

[This retracts the article DOI: 10.1155/2022/9150205.].

Microneedles: A Versatile Drug Delivery Carrier for Phytobioactive Compounds as a Therapeutic Modulator for Targeting Mitochondrial Dysfunction in the Management of Neurodegenerative Diseases

Neurodegenerative disease (ND) is the fourth leading cause of death worldwide, with limited symptomatic therapies. Mitochondrial dysfunction is a major risk factor in the progression of ND, and it-increases the generation of reactive oxygen species (ROS). Overexposure to these ROS induces apoptotic changes leading to neuronal cell death. Many studies have shown the prominent effect of phytobioactive compounds in managing mitochondrial dysfunctions associated with ND, mainly due to their antioxidant properties. The drug delivery to the brain is limited due to the presence of the blood-brain barrier (BBB), but effective drug concentration needs to reach the brain for the therapeutic action. Therefore, developing safe and effective strategies to enhance drug entry in the brain is required to establish ND's treatment. The microneedle-based drug delivery system is one of the effective non-invasive techniques for drug delivery through the transdermal route. Microneedles are micronsized drug delivery needles that are self-administrable. It can penetrate through the stratum corneum skin layer without hitting pain receptors, allowing the phytobioactive compounds to be released directly into systemic circulation in a controlled manner. With all of the principles mentioned above, this review discusses microneedles as a versatile drug delivery carrier for the phytoactive compounds as a therapeutic potentiating agent for targeting mitochondrial dysfunction for the management of ND.

Solid Lipid Nanoparticles Containing Dopamine and Grape Seed Extract: Freeze-Drying with Cryoprotection as a Formulation Strategy to Achieve Nasal Powders

(1) Background: DA-Gelucire® 50/13-based solid lipid nanoparticles (SLNs) administering the neurotransmitter dopamine (DA) and the antioxidant grape-seed-derived proanthocyanidins (grape seed extract, GSE) have been prepared by us in view of a possible application for Parkinson's disease (PD) treatment. To develop powders constituted by such SLNs for nasal administration, herein, two different agents, namely sucrose and methyl-β-cyclodextrin (Me-β-CD), were evaluated as cryoprotectants. (2) Methods: SLNs were prepared following the melt homogenization method, and their physicochemical features were investigated by Raman spectroscopy, Scanning Electron Microscopy (SEM), atomic force microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). (3) Results: SLN size and zeta potential values changed according to the type of cryoprotectant and the morphological features investigated by SEM showed that the SLN samples after lyophilization appear as folded sheets with rough surfaces. On the other hand, the AFM visualization of the SLNs showed that their morphology consists of round-shaped particles before and after freeze-drying. XPS showed that when sucrose or Me-β-CD were not detected on the surface (because they were not allocated on the surface or completely absent in the formulation), then a DA surfacing was observed. In vitro release studies in Simulated Nasal Fluid evidenced that DA release, but not the GSE one, occurred from all the cryoprotected formulations. Finally, sucrose increased the physical stability of SLNs better than Me-β-CD, whereas RPMI 2650 cell viability was unaffected by SLN-sucrose and slightly reduced by SLN-Me-β-CD. (4) Conclusions: Sucrose can be considered a promising excipient, eliciting cryoprotection of the investigated SLNs, leading to a powder nasal pharmaceutical dosage form suitable to be handled by PD patients.

Nanophytomedicines as Therapeutic Agents for Parkinson's Disease

Phytochemicals are promising therapeutics for various neurodegenerative disorders, including Parkinson's disease (PD). However, their efficacy, pharmacokinetic properties, and penetration across the blood-brain barrier can be improved using delivery systems such as nanoparticles. We reviewed recently published work in which nanoparticles were used to deliver phytochemicals toward PD treatment. The studies show that nanoparticles not only improve the pharmacological effect of the phytochemicals but also enable targeting to the brain and crossing of the blood-brain barrier. Various ligands were added to the nanoparticles to improve blood-brain barrier transportation. The promising findings from the published studies reveal that more research into nanophytomedicine approaches as therapeutic targets for PD is warranted, especially since they have the potential to protect against key features of PD, including α-synuclein aggregation, mitochondrial dysfunction, and dopaminergic neuronal death. Furthermore, future directions should involve smart designs to tailor nanoparticles for improved therapeutic delivery by modifying their features, such as architecture, surface and material properties, targeting ligands, and responsiveness.

Nanomedicine strategies for central nervous system (CNS) diseases

The blood-brain barrier (BBB) is a crucial part of brain anatomy as it is a specialized, protective barrier that ensures proper nutrient transport to the brain, ultimately leading to regulating proper brain function. However, it presents a major challenge in delivering pharmaceuticals to treat central nervous system (CNS) diseases due to this selectivity. A variety of different vehicles have been designed to deliver drugs across this barrier to treat neurodegenerative diseases, greatly impacting the patient's quality of life. The two main types of vehicles used to cross the BBB are polymers and liposomes, which both encapsulate pharmaceuticals to allow them to transcytose the cells of the BBB. For Alzheimer's disease, Parkinson's disease, multiple sclerosis, and glioblastoma brain cancer, there are a variety of different nanoparticle treatments in development that increase the bioavailability and targeting ability of existing drugs or new drug targets to decrease symptoms of these diseases. Through these systems, nanomedicine offers a new way to target specific tissues, especially for the CNS, and treat diseases without the systemic toxicity that often comes with medications used currently.

The use of cellulose, chitosan and hyaluronic acid in transdermal therapeutic management of obesity: A review

Obesity is a clinical condition with rising popularity and detrimental impacts on human health. According to the World Health Organization, obesity is the sixth most common cause of death worldwide. It is challenging to combat obesity because medications that are successful in the clinical investigation have harmful side effects when administered orally. The conventional approaches for treating obesity primarily entail synthetic compounds and surgical techniques but possess severe adverse effects and recurrences. As a result, a safe and effective strategy to combat obesity must be initiated. Recent studies have shown that biological macromolecules of the carbohydrate class, such as cellulose, hyaluronic acid, and chitosan, can enhance the release and efficacy of medications for obesity but due to their short biological half-lives and poor oral bioavailability, their distribution rate is affected. This helps to comprehend the need for an effective therapeutic approach via a transdermal drug delivery system. This review focuses on the transdermal administration, utilizing cellulose, chitosan, and hyaluronic acid via microneedles, as it offers a promising solution to overcome existing therapy limitations in managing obesity and it also highlights how microneedles can effectively deliver therapeutic substances through the skin's outer layer, bypassing pain receptors and specifically targeting adipose tissue.

Current advancements related to phytobioactive compounds based liposomal delivery for neurodegenerative diseases

Neurodegenerative diseases are the most widely affected disease condition in an aging population. The treatment available reduces the elevated manifestations but is ineffective due to the drug's poor bioavailability, plasma stability, and permeability across the blood-brain barrier (BBB). Until now, no therapeutic compound has been able to stop the progression of neurodegenerative disease. Even the available therapeutic moiety manages it with possible adverse effects up to the later stage. Hence, phytobioactive compounds of plant origin offer effective treatment strategies against neurodegenerative diseases. The only difficulty of these phytobioactive compounds is permeability across the BBB. Engineered nanocarriers such as liposomes provide high lipid permeability across BBB. Liposomes have unique physicochemical properties that are widely investigated for their application in diagnosing and treating neurodegenerative diseases. The surface modification on liposomes by peptides, antibodies, and RNA aptamers offers receptor targeting. These brain-targeted approaches by liposomes improve the efficacy of phytoconstituents. Additional surface modification methods are utilized on liposomes, which increases the brain-targeted delivery of phytobioactive compounds. The marketing strategy of the liposomal delivery system is in its peak mode, where it has the potential to modify the existing therapy. This review will summarize the brain target liposomal delivery of phytobioactive compounds as a novel disease-modifying agent for treating neurodegenerative diseases.