Inhalable Formulation Based on Lipid-Polymer Hybrid Nanoparticles for the Macrophage Targeted Delivery of Roflumilast

Diving into RNAi Therapy: An Inhalable Formulation Based on Lipid-Polymer Hybrid Systems for Pulmonary Delivery of siRNA

Here, a pulmonary formulation based on lipid-polymer hybrid nanoparticles carrying small interfering RNA (siRNA) was developed to realize a RNA interference-based therapy to treat respiratory diseases. Toward this aim, a new copolymer was synthesized, by functionalization of the α,β-poly(N-2-hydroxyethyl)-d,l-aspartamide with 35 mol % of 1,2-bis(3-aminopropylamino)ethane, 0.4 mol % of fluorescent dye, and 4.5 mol % of poly(lactic-co-glycolic acid). This was used to encapsulate siRNA targeting the green fluorescent protein (siGFP), within a lipid shell made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and 1,2-distearoyl-sn-glycero-phosphoethanolamine-N-(polyethylene glycol)2000. siGFP-loaded lipid-polymer hybrid nanoparticles (LPHFNPs@siGFP) exhibited colloidal size (∼164 nm), positive ζ potential, high siRNA encapsulation efficiency (∼99%), and a core-shell morphology. They showed high cellular uptake and a gene silencing efficiency of ∼50% in human lung cancer cells expressing GFP. To address aerodynamic challenges, LPHFNPs@siGFP were spray-dried with trehalose, yielding spherical particles (∼3 μm) with 80% siRNA encapsulation efficiency, excellent aerosolization properties, and a gene silencing efficiency comparable to the fresh LPHFNPs@siGFP sample.

Exploiting inhalable microparticles incorporating hybrid polymer-lipid nanoparticles loaded with Iloprost manages lung hyper-inflammation

This study focuses on developing of a novel inhalation therapy for managing lung hyper-inflammation, producing hybrid polymer-lipid nanoparticles loaded with Iloprost (Ilo). These nanoparticles showed a size of approximately 100 nm with a core-shell structure and provided prolonged drug release, reaching 28 wt% after 6 h of incubation. The phospholipid composition and quantity (64 wt% on the total sample weight) result in minimal interaction with mucin and a significant effect on the rheology of a cystic fibrosis mucus model, in terms of reducing complex viscosity. To obtain an inhalable microparticulate matrix suitable for incorporating Ilo@PEG-LPHNPs, the qualitative and quantitative composition of the feed fluid for the spray drying (SD) process was optimized. The selected composition (10 % wt/vol of mannitol and 10 % wt of ammonium bicarbonate relative to the weight of mannitol) was used to produce Nano-into Microparticles (NiM). The characterization of NiM revealed excellent aerodynamic properties, with a Mass Median Aerodynamic Diameter (MMAD) of 4.34 μm and a Fine Particle Fraction (FPF) of approximately 57 %. Biological characterization revealed that the particles are non-toxic to 16-HBE cells and can effectively evade macrophage uptake, likely due to the presence of PEG in their composition. Moreover, the delivered Iloprost significantly downregulates the production of the pro-inflammatory cytokine IL-6, showing the therapeutic potential of this drug delivery system.

Lipid-Polymer Hybrid Nanoparticles in Microparticle-Based Powder: Evaluating the Potential of Methylprednisolone Delivery for Future Lung Disease Treatment via Inhalation

BACKGROUND

Lipid-polymer hybrid nanoparticles (LPHNPs) offer a promising method for delivering methylprednisolone (MePD) to treat lung inflammation, addressing aggregation issues seen with polymer-only formulations.

OBJECTIVES

This study aimed to develop LPHNPs for MePD delivery, assessing their physicochemical properties, drug loading, cytocompatibility, and release profiles, ultimately enabling inhalable microparticle-based powder.

METHODS

The nanoparticles were formulated using α,β-poly(N-2-hydroxyethyl)-DL-aspartamide-g-Rhodamine B-g-poly(lactic acid) (PHEA-g-RhB-g-PLA) and phospholipids DPPC, DOTAP, and DSPE-PEG2000 in a 45:30:25 weight ratio. Their size, redispersion after freeze-drying, drug loading (DL%), and controlled release were evaluated. Cytocompatibility was assessed on 16-HBE cell lines, measuring anti-inflammatory effects via IL-6 and IL-8 levels. Spray drying was optimized to produce microparticles using mannitol (MAN), leucine (LEU), and N-acetylcysteine (NAC).

RESULTS

The nanoparticles had a size of 186 nm and a DL% of 2.9% for MePD. They showed good cytocompatibility, significantly reducing IL-6 and IL-8 levels. Spray drying yielded microparticles with a fine particle fraction (FPF) of 62.3% and a mass median aerodynamic diameter (MMAD) of 3.9 µm. Inclusion of LPHNPs@MePD (0.25% w/v) resulted in FPF and MMAD values of 56.7% and 4.4 µm. In conclusion, this study described the production of novel inhalable powders as carriers for MePD-loaded nanostructures with favorable physicochemical properties, cytocompatibility, and promising aerosol performance, indicating their potential as an effective inhalable therapy for lung inflammation with corticosteroids, especially for treating chronic diseases.

Review on the Use of Difluprednate in Inflammatory Eye Disorders: The Topical Steroid That Goes the Distance

Difluprednate (DFP) (difluoroprednisolone butyrate acetate, or DFBA) ophthalmic emulsion 0.05% (Durezol®) was the first potent corticosteroid to be approved for both postoperative pain and inflammation in 2008. In June 2012, it was approved for the treatment of endogenous anterior uveitis. It is a synthetic difluorinated prednisolone derivative that was originally developed in Japan as a dermatologic ointment. The glucocorticoid binding affinity of its active metabolite was demonstrated to be 56 times stronger than prednisolone. Experimental models showed that it reached the anterior and posterior segments of the eye quickly, via both transcorneal and noncorneal (conjunctiva and sclera) absorption routes. Its clinical applications have been expanded to treat patients with uveitic macular edema and anterior scleritis. Case reports and case series also describe its use in some forms of posterior uveitis and in non-uveitic entities. Elevated intraocular pressure and acceleration of cataract formation are the main concerns with DFP as with all corticosteroids. Because IOP elevation is particularly pronounced in the pediatric age group, IOP is to be closely monitored at every visit in children. High incidence of cataract formation and progression was also documented in children, thus necessitating vigilant follow-up of children on chronic treatment. This review aims to give a comprehensive and up-to-date overview of difluprednate's pharmacological properties, clinical applications, safety profiles, and alternative delivery methods.

Application of nano- and micro-particle-based approaches for selected bronchodilators in management of asthma

Asthma is a chronic inflammatory condition that affects the airways, posing a substantial health threat to a large number of people worldwide. Bronchodilators effectively alleviate symptoms of airway obstruction by inducing relaxation of the smooth muscles in the airways, thereby reducing breathlessness and enhancing overall quality of life. The drug targeting to lungs poses significant challenges; however, this issue can be resolved by employing nano- and micro-particles drug delivery systems. This review provides brief insights about underlying mechanisms of asthma, including the role of several inflammatory mediators that contribute to the development and progression of this disease. This article provides an overview of the physicochemical features, pharmacokinetics, and mechanism of action of particular groups of bronchodilators, including sympathomimetics, PDE-4 inhibitors (phosphodiesterase-4 inhibitors), methylxanthines, and anticholinergics. This study presents a detailed summary of the most recent developments in incorporation of bronchodilators in nano- and micro-particle-based delivery systems which include solid lipid nanoparticles, bilosomes, novasomes, liposomes, polymeric nano- and micro-particles. Specifically, it focuses on breakthroughs in the categories of sympathomimetics, methylxanthines, PDE-4 inhibitors, and anticholinergics. These medications have the ability to specifically target alveolar macrophages, leading to a higher concentration of pharmaceuticals in the lung tissues.

Lipid polymer hybrid nanoparticles against lung cancer and their application as inhalable formulation

Lung cancer is a leading cause of global cancer mortality, often treated with chemotherapeutic agents. However, conventional approaches such as oral or intravenous administration of drugs yield low bioavailability and adverse effects. Nanotechnology has unlocked new gateways for delivering medicine to their target sites. Lipid-polymer hybrid nanoparticles (LPHNPs) are one of the nano-scaled delivery platforms that have been studied to exploit advantages of liposomes and polymers, enhancing stability, drug loading, biocompatibility and controlled release. Pulmonary administration of drug-loaded LPHNPs enables direct lung deposition, rapid onset of action and heightened efficacy at low doses of drugs. In this manuscript, we will review the potential of LPHNPs in management of lung cancer through pulmonary administration.

Inhaled Ivermectin-Loaded Lipid Polymer Hybrid Nanoparticles: Development and Characterization

Ivermectin (IVM), a drug originally used for treating parasitic infections, is being explored for its potential applications in cancer therapy. Despite the promising anti-cancer effects of IVM, its low water solubility limits its bioavailability and, consequently, its biological efficacy as an oral formulation. To overcome this challenge, our research focused on developing IVM-loaded lipid polymer hybrid nanoparticles (LPHNPs) designed for potential pulmonary administration. IVM-loaded LPHNPs were developed using the emulsion solvent evaporation method and characterized in terms of particle size, morphology, entrapment efficiency, and release pattern. Solid phase characterization was investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Using a Twin stage impinger (TSI) attached to a device, aerosolization properties of the developed LPHNPs were studied at a flow rate of 60 L/min, and IVM was determined by a validated HPLC method. IVM-loaded LPHNPs demonstrated spherical-shaped particles between 302 and 350 nm. Developed formulations showed an entrapment efficiency between 68 and 80% and a sustained 50 to 60% IVM release pattern within 96 h. Carr's index (CI), Hausner ratio (HR), and angle of repose (θ) indicated proper flowability of the fabricated LPHNPs. The in vitro aerosolization analysis revealed fine particle fractions (FPFs) ranging from 18.53% to 24.77%. This in vitro study demonstrates the potential of IVM-loaded LPHNPs as a delivery vehicle through the pulmonary route.

A new frontier in precision medicine: Exploring the role of extracellular vesicles in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease characterized by progressive respiratory difficulties. It has a high incidence and disability rate worldwide. However, currently there is still a lack of highly effective treatment methods for COPD, only symptom relief is possible. Therefore, there is an urgent need to explore new treatment options. Almost all cells can secrete extracellular vesicles (EVs), which participate in many physiological activities by transporting cargoes and are associated with the pathogenesis of various diseases. Recently, many scholars have extensively studied the relationship between COPD and EVs, which has strongly demonstrated the significant impact of EVs from different sources on the occurrence and development of COPD. Therefore, EVs are a good starting point and new opportunity for the diagnosis and treatment of COPD. In this review, we mainly describe the current mechanisms of EVs in the pathogenesis of COPD, also the relationship between diagnosis, prognosis, and treatment. At the same time, we also introduce some new methods for COPD therapy based on EVs. It is hoped that this article can provide new ideas for future research and contribute to the development of precision medicine.

Nanomedicines for targeted pulmonary delivery: receptor-mediated strategy and alternatives

Pulmonary drug delivery of nanomedicines is promising for the treatment of lung diseases; however, their lack of specificity required for targeted delivery limit their applications. Recently, a variety of pulmonary delivery targeting nanomedicines (PDTNs) has been developed for enhancing drug accumulation in lung lesions and reducing systemic side effects. Furthermore, with the increasing profound understanding of the specific microenvironment of different local lung diseases, multiple targeting strategies have been employed to promote drug delivery efficiency, which can be divided into the receptor-mediated strategy and alternatives. In this review, the current publication trend on PDTNs is analyzed and discussed, revealing that the research in this area has been attracting much attention. According to the different unique microenvironments of lung lesions, the reported PDTNs based on the receptor-mediated strategy for lung cancer, lung infection, lung inflammation and pulmonary fibrosis are listed and summarized. In addition, several other well-established strategies for the design of these PDTNs, such as charge regulation, mucus delivery enhancement, stimulus-responsive drug delivery and magnetic force-driven targeting, are introduced and discussed. Besides, bottlenecks in the development of PDTNs are discussed. Finally, we highlight the challenges and opportunities in the development of PDTNs. We hope that this review will provide an overview of the available PDTNs for guiding the treatment of lung diseases.

Biomimetic Nano-Drug Delivery System: An Emerging Platform for Promoting Tumor Treatment

With the development of nanotechnology, nanoparticles (NPs) have shown broad prospects as drug delivery vehicles. However, they exhibit certain limitations, including low biocompatibility, poor physiological stability, rapid clearance from the body, and nonspecific targeting, which have hampered their clinical application. Therefore, the development of novel drug delivery systems with improved biocompatibility and high target specificity remains a major challenge. In recent years, biofilm mediated biomimetic nano-drug delivery system (BNDDS) has become a research hotspot focus in the field of life sciences. This new biomimetic platform uses bio-nanotechnology to encapsulate synthetic NPswithin biomimetic membrane, organically integrating the low immunogenicity, low toxicity, high tumor targeting, good biocompatibility of the biofilm with the adjustability and versatility of the nanocarrier, and shows promising applications in the field of precision tumor therapy. In this review, we systematically summarize the new progress in BNDDS used for optimizing drug delivery, providing a theoretical reference for optimizing drug delivery and designing safe and efficient treatment strategies to improve tumor treatment outcomes.

Rapamycin-based inhaled therapy for potential treatment of COPD-related inflammation: production and characterization of aerosolizable nano into micro (NiM) particles

Our paper describes the production and characterization of inhalable microparticles loaded with nanoparticles for the lung administration of rapamycin (Rapa). In detail, core-shell lipid/polymer hybrid nanoparticles loaded with Rapa (Rapa@Man-LPHNPs) were produced with mean size of about 128 nm and slightly negative ζ potential (-13.8 mV). A fluorescent graft polyaspartamide-poly(lactic-co-glycolic acid) copolymer (PHEA-g-RhB-g-PLGA) for use as the polymeric core was obtained by nanoprecipitation, while an appropriate mixture of DPPC and mannosylated phospholipid (DSPE-PEG2000-Man) was used to provide the macrophage-targeting lipid shell. The successful formation of Rapa@Man-LPHNPs was confirmed by TEM and DSC analyses. The loaded drug (4.3 wt% of the total weight) was slowly released from the polymeric core and protected from hydrolysis, with the amount of intact drug after 24 h of incubation in the medium being equal to 74 wt% (compared to 40% when the drug is freely incubated at the same concentration). To obtain a formulation administrable by inhalation, Rapa@Man-LPHNPs were entrapped inside PVA : LEU microparticles by using the nano into micro (NiM) strategy, specifically by spray drying (SD) in the presence of a pore-forming agent. In this way, NiM particles with geometric and theoretical aerodynamic diameters equal to 4.52 μm and 3.26 μm, respectively, were obtained. Furthermore, these particles showed optimal nebulization performance, having an FPF and an MMAD equal to 27.5% and 4.3 μm, respectively.

Lipidated brush-PEG polymers as low molecular weight pulmonary drug delivery platforms

OBJECTIVES

Nanomedicines are being actively developed as inhalable drug delivery systems. However, there is a distinct utility in developing smaller polymeric systems that can bind albumin in the lungs. We therefore examined the pulmonary pharmacokinetic behavior of a series of lipidated brush-PEG (5 kDa) polymers conjugated to 1C2, 1C12 lipid or 2C12 lipids.

METHODS

The pulmonary pharmacokinetics, patterns of lung clearance and safety of polymers were examined in rats. Permeability through monolayers of primary human alveolar epithelia, small airway epithelia and lung microvascular endothelium were also investigated, along with lung mucus penetration and cell uptake.

RESULTS

Polymers showed similar pulmonary pharmacokinetic behavior and patterns of lung clearance, irrespective of lipid molecular weight and albumin binding capacity, with up to 30% of the dose absorbed from the lungs over 24 h. 1C12-PEG showed the greatest safety in the lungs. Based on its larger size, 2C12-PEG also showed the lowest mucus and cell membrane permeability of the three polymers. While albumin had no significant effect on membrane transport, the cell uptake of C12-conjugated PEGs were increased in alveolar epithelial cells.

CONCLUSION

Lipidated brush-PEG polymers composed of 1C12 lipid may provide a useful and novel alternative to large nanomaterials as inhalable drug delivery systems.

Recent Updates in Inhalable Drug Delivery System against Various Pulmonary Diseases: Challenges and Future Perspectives

In the current scenario, pulmonary disease has become a prime burden for morbidity and mortality alongside tremendous social and economic crises throughout the world. Numerous conventional drug delivery system and treatment approach targeting the respiratory region has been driven out. However, effective and accurate recovery has not been achieved yet. In this regard, nanotechnological- based inhalable drug delivery strategy including polymeric, lipidic, or metallic-based respirable microparticles plays an indispensable role in circumventing numerous challenges faced during traditional treatment. Excellent aerodynamic performance leads to enhanced lung targetability, reduced dosing frequency and hence systemic toxicities, as well as improved pharmaceutical attributes, and therefore pharmacokinetic profiles are interminable factors associated with nanotechnologicalbased inhalable delivery. In this review, we comprehensively explored recent advancements in nanotechnologically engineered inhalable formulations targeting each of the mentioned pulmonary diseases. Moreover, we systematically discussed possible respiratory or systemic toxicities about the indeterminate and undefined physicochemical characteristics of inhaled particles.

Cigarette Smoke-Induced Respiratory Response: Insights into Cellular Processes and Biomarkers

Cigarette smoke (CS) poses a significant risk factor for respiratory, vascular, and organ diseases owing to its high content of harmful chemicals and reactive oxygen species (ROS). These substances are known to induce oxidative stress, inflammation, apoptosis, and senescence due to their exposure to environmental pollutants and the presence of oxidative enzymes. The lung is particularly susceptible to oxidative stress. Persistent oxidative stress caused by chronic exposure to CS can lead to respiratory diseases such as chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), and lung cancer. Avoiding exposure to environmental pollutants, like cigarette smoke and air pollution, can help mitigate oxidative stress. A comprehensive understanding of oxidative stress and its impact on the lungs requires future research. This includes identifying strategies for preventing and treating lung diseases as well as investigating the underlying mechanisms behind oxidative stress. Thus, this review aims to investigate the cellular processes induced by CS, specifically inflammation, apoptosis, senescence, and their associated biomarkers. Furthermore, this review will delve into the alveolar response provoked by CS, emphasizing the roles of potential therapeutic target markers and strategies in inflammation and oxidative stress.

Phosphodiesterase inhibitors and lung diseases

Phosphodiesterase enzymes (PDE) have long been known as regulators of cAMP and cGMP, second messengers involved in various signaling pathways and expressed in a variety of cell types implicated in respiratory diseases such as airway smooth muscle and inflammatory cells making them a key target for the treatment of lung diseases as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, and pulmonary hypertension (PH). The first reported PDE inhibitor was the xanthine, theophylline, described as a non-specific PDE inhibitor and whilst this drug is effective, it also has a range of unwanted side effects. In an attempt to improve the therapeutic window of xanthines, a number of selective PDE inhibitors have been developed for the treatment of respiratory diseases with only the selective PDE 4 inhibitor, roflumilast, being approved for the treatment of severe COPD. However, roflumilast also has a very narrow therapeutic window due to a number of important doses limiting side effects, particularly in the gastrointestinal tract. However, there continues to be research carried out in this field to identify improved selective PDE inhibitors, both by targeting other PDE subtypes (e.g., PDE 7 found in a number of inflammatory and immune cells) and through development of selective PDE inhibitors for pulmonary administration to reduce systemic exposure and improve the side effect profile. This approach has been exemplified by the development of ensifentrine, a dual PDE 3-PDE 4 inhibitor, an inhaled drug that has recently completed two successful Phase III clinical trials in patients with COPD.

Investigating the Effectiveness of Difluprednate-Loaded Core-Shell Lipid-Polymeric Hybrid Nanoparticles for Ocular Delivery

Uveitis is a sight-threatening disease that causes inflammation in the uvea; difluprednate (DFB) is the first approved drug molecule for postoperative pain, inflammation, and endogenous uveitis. Complex ocular physiology and structure make it difficult to deliver drugs to the eye. Increased permeation and retention in the layer of the eye are required to improve the bioavailability of ocular drugs. In the current research investigation, DFB-loaded lipid polymer hybrid nanoparticles (LPHNPs) were designed and fabricated to enhance the corneal permeation and sustained release of DFB. A well-established two-step approach was used to fabricate the DFB-LPHNPs, comprising of Poly-Lactic-co-Glycolic Acid (PLGA) core that entrapped the DFB and DFB loaded PLGA NPs covered by lipid shell. The manufacturing parameters were optimized for the preparation of DFB-LPHNPs; the optimal DFB-LPHNPs showed a mean particle size of 117.3±2.9 nm, suitable for ocular administration and high entrapment efficiency of 92.45 ± 2.17 % with neutral pH (7.18 ±0.02) and isotonic Osmolality (301±3 mOsm/kg). Microscopic examination confirms the core-shell morphological structure of DFB-LPHNPs. The prepared DFB-LPHNPs were extensively characterized using spectroscopic techniques and physicochemical characterization, which confirms the entrapment of the drug and the formation of the DFB-LPHNPs. The confocal laser scanning microscopy studies revealed that Rhodamine B-loaded LPHNPs were penetrated into stromal layers of the cornea in ex-vivo conditions. The DFB-LPHNPs showed a sustained release pattern in simulated tear fluid and 4- folds enhanced permeation of DFB as compared to pure DFB solution. The ex-vivo histopathological studies revealed that DFB-LPHNPs didn't cause any damage or no alteration in the cellular structure of the cornea. Additionally, the results of the HET-CAM assay confirmed that the DFB-LPHNPs were not toxic for ophthalmic administration.

Developing Antibiofilm Fibrillar Scaffold with Intrinsic Capacity to Produce Silver Nanoparticles

The development of biomedical systems with antimicrobial and antibiofilm properties is a difficult medical task for preventing bacterial adhesion and growth on implanted devices. In this work, a fibrillar scaffold was produced by electrospinning a polymeric organic dispersion of polylactic acid (PLA) and poly(α,β-(N-(3,4-dihydroxyphenethyl)-L-aspartamide-co-α,β-N-(2-hydroxyethyl)-L-aspartamide) (PDAEA). The pendant catechol groups of PDAEA were used to reduce silver ions in situ and produce silver nanoparticles onto the surface of the electrospun fibers through a simple and reproducible procedure. The morphological and physicochemical characterization of the obtained scaffolds were studied and compared with virgin PLA electrospun sample. Antibiofilm properties against Pseudomonas aeruginosa, used as a biofilm-forming pathogen model, were also studied on planar and tubular scaffolds. These last were fabricated as a proof of concept to demonstrate the possibility to obtain antimicrobial devices with different shape and dimension potentially useful for different biomedical applications. The results suggest a promising approach for the development of antimicrobial and antibiofilm scaffolds.