Inhalation properties of water-soluble drug loaded liposomes atomized by nebulizer

Inhaled nano-based therapeutics for pulmonary fibrosis: recent advances and future prospects

It is reported that pulmonary fibrosis has become one of the major long-term complications of COVID-19, even in asymptomatic individuals. Currently, despite the best efforts of the global medical community, there are no treatments for COVID-induced pulmonary fibrosis. Recently, inhalable nanocarriers have received more attention due to their ability to improve the solubility of insoluble drugs, penetrate biological barriers of the lungs and target fibrotic tissues in the lungs. The inhalation route has many advantages as a non-invasive method of administration and the local delivery of anti-fibrosis agents to fibrotic tissues like direct to the lesion from the respiratory system, high delivery efficiency, low systemic toxicity, low therapeutic dose and more stable dosage forms. In addition, the lung has low biometabolic enzyme activity and no hepatic first-pass effect, so the drug is rapidly absorbed after pulmonary administration, which can significantly improve the bioavailability of the drug. This paper summary the pathogenesis and current treatment of pulmonary fibrosis and reviews various inhalable systems for drug delivery in the treatment of pulmonary fibrosis, including lipid-based nanocarriers, nanovesicles, polymeric nanocarriers, protein nanocarriers, nanosuspensions, nanoparticles, gold nanoparticles and hydrogel, which provides a theoretical basis for finding new strategies for the treatment of pulmonary fibrosis and clinical rational drug use.

Nanomedicine-mediated therapeutic approaches for pulmonary arterial hypertension

Nanomedicine has emerged as a field in which there are opportunities to improve the diagnosis, treatment and prevention of incurable diseases. Pulmonary arterial hypertension (PAH) is known as a severe and fatal disease affecting children and adults. Conventional treatments have not produced optimal effectiveness in treating this condition. Several reasons for this include drug instability, poor solubility of the drug and a shortened duration of pharmacological action. The present review focuses on new approaches for delivering anti-PAH drugs using nanotechnology with the aim of overcoming these shortcomings and increasing their efficacy. Solid-lipid nanoparticles, liposomes, metal-organic frameworks and polymeric nanoparticles have demonstrated advantages for the potential treatment of PAH, including increased drug bioavailability, drug solubility and accumulation in the lungs.

Development and Optimisation of Inhalable EGCG Nano-Liposomes as a Potential Treatment for Pulmonary Arterial Hypertension by Implementation of the Design of Experiments Approach

Epigallocatechin gallate (EGCG), the main ingredient in green tea, holds promise as a potential treatment for pulmonary arterial hypertension (PAH). However, EGCG has many drawbacks, including stability issues, low bioavailability, and a short half-life. Therefore, the purpose of this research was to develop and optimize an inhalable EGCG nano-liposome formulation aiming to overcome EGCG's drawbacks by applying a design of experiments strategy. The aerodynamic behaviour of the optimum formulation was determined using the next-generation impactor (NGI), and its effects on the TGF-β pathway were determined using a cell-based reporter assay. The newly formulated inhalable EGCG liposome had an average liposome size of 105 nm, a polydispersity index (PDI) of 0.18, a zeta potential of -25.5 mV, an encapsulation efficiency of 90.5%, and a PDI after one month of 0.19. These results are in complete agreement with the predicted values of the model. Its aerodynamic properties were as follows: the mass median aerodynamic diameter (MMAD) was 4.41 µm, the fine particle fraction (FPF) was 53.46%, and the percentage of particles equal to or less than 3 µm was 34.3%. This demonstrates that the novel EGCG liposome has all the properties required to be inhalable, and it is expected to be deposited deeply in the lung. The TGFβ pathway is activated in PAH lungs, and the optimum EGCG nano-liposome inhibits TGFβ signalling in cell-based studies and thus holds promise as a potential treatment for PAH.

Liposomal remdesivir inhalation solution for targeted lung delivery as a novel therapeutic approach for COVID-19

Strong infectivity enables coronavirus disease 2019 (COVID-19) to rage throughout the world. Moreover, the lack of drugs with definite therapeutic effects further aggravates the spread of the pandemic. Remdesivir is one of the most promising anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) drugs. However, the limited clinical effects make its therapeutic effect controversial, which may result from the poor accumulation and activation of remdesivir in the lung. Therefore, we developed lyophilized remdesivir liposomes (Rdv-lips) which can be reconstituted as liposomal aerosol for pulmonary delivery to improve the in vivo behavior of existing remdesivir cyclodextrin conclusion compound (Rdv-cyc) injections. Liposome encapsulation endowed remdesivir with much higher solubility and better biocompatibility. The in vitro liposomal aerosol characterization demonstrated that Rdv-lips possessed a mass median aerodynamic diameter of 4.118 µm and fine particle fraction (<5 µm) higher than 50%, indicating good pulmonary delivery properties. Compared to the Rdv-cyc intravenous injection group, the Rdv-lips inhalation group displayed a nearly 100-fold increase in the remdesivir-active metabolite nucleotide triphosphate (NTP) concentration and better NTP accumulation in the lung than the Rdv-cyc inhalation group. A faster transition from remdesivir to NTP of Rdv-lips (inhalation) could also be observed due to better cell uptake. Compared to other preparations, the superiority of Rdv-lips was further evidenced by the results of an in vivo safety study, with little possibility of inducing inflammation. In conclusion, Rdv-lips for pulmonary delivery will be a potent formulation to improve the in vivo behavior of remdesivir and exert better therapeutic effects in COVID-19 treatment.

Aerosolized nanoliposomal carrier of remdesivir: an effective alternative for COVID-19 treatment in vitro

Aim: To formulate an aerosolized nanoliposomal carrier for remdesivir (AL-Rem) against coronavirus disease 2019. Methods: AL-Rem was prepared using modified hydration technique. Cytotoxicity in lung adenocarcinoma cells, stability and aerodynamic characteristics of developed liposomes were evaluated. Results: AL-Rem showed high encapsulation efficiency of 99.79%, with hydrodynamic diameter of 71.46 ± 1.35 nm and surface charge of -32 mV. AL-Rem demonstrated minimal cytotoxicity in A549 cells and retained monolayer integrity of Calu-3 cells. AL-Rem showed sustained release, with complete drug release obtained within 50 h in simulated lung fluid. Long-term stability indicated >90% drug recovery at 4°C. Desirable aerosol performance, with mass median aerodynamic diameter of 4.56 ± 0.55 and fine particle fraction of 74.40 ± 2.96%, confirmed successful nebulization of AL-Rem. Conclusion: AL-Rem represents an effective alternative for coronavirus disease 2019 treatment.

Liquid–Solid Core-Shell Microcapsules of Calcium Carbonate Coated Emulsions and Liposomes

Micron-sized core-shell particles consisting of a calcium carbonate (CaCO3) mineral shell and a fluidic core were generated using a biomimetic approach, for the purpose of use as biodegradable microcapsules for release of active agents. Dinoflagellate cysts, unicellular organisms which deposit a protective hard mineral shell around their soft and fluidic cellular interior, served as our inspiration. Using the biomimetic polymer-induced liquid-precursor (PILP) mineralization process, calcium carbonate coatings were deposited on charged emulsion droplets and liposomes. Light microscopy, scanning electron microscopy, polarized light microscopy, X-ray diffraction, and confocal fluorescence microscopy were used to demonstrate that smooth CaCO3 mineral coatings can be deposited onto the high curvature surfaces of emulsions and liposomes to yield micron-sized microcapsules for the effective entrapment of both hydrophobic and hydrophilic active agents. These biodegradable and biocompatible CaCO3 microcapsules are novel systems for producing a powdered form of fluid-containing capsules for storage and transport of pharma/chemical agents. They may be used in lieu of, or in conjunction with, existing microcapsule delivery approaches, as well as providing a convenient foundation for which polymeric coatings could be further applied, allowing for more complex targeting and/or chemical-release control.

Characterization and comparison of Re-Du-Ning aerosol particles generated by different jet nebulizers

Inhalation therapy is the first-line therapy for the treatment of respiratory diseases. Re-Du-Ning inhalation solution (RIS) is an aerosol derivative from the Re-Du-Ning injection and has been clinically used to treat respiratory diseases like pneumonia for more than twenty years in China. However, the aerosolization and inhalation performances of RIS using different nebulizers have not been characterized, which may affect the therapeutic effects of RIS on respiratory diseases. We investigated the inhalation performances of RIS using five different nebulizers utilizing Spraytec, breath simulator of BRS 2000 and NGI techniques. We tested 5 different types of jet nebulizer, using RIS and an adult breathing pattern, to determine the difference in aerosol delivery over time. The particle size distribution of RIS was monitored by a Spraytec laser particle sizer. Fine particle fraction (FPF) and mass median aerodynamic diameter (MMAD) for RIS were measured using NGI. Aerosol deposited on the filter was analysed using HPLC. Nebulization time was much longer for the Pari Boy SX (red) nebulizer than for the other nebulizers, with the minimum delivery rate (DR) and the maximum total delivered dose (TDD) and total exhalation dose (TED). Nebulization time for Pari Boy SX (blue) was the lowest, with the highest DR and the lowest TDD and TED. Furthermore, the aerodynamic particle size of RIS was much larger for the Pari blue and Pari LC Plus than other nebulizers. Pari red produced the smallest aerodynamic particle size of RIS in these five nebulizers. In addition, a good linear relationship was found between MMAD and D₅₀ in these five nebulizers. The results demonstrated that Pari Boy SX (red) delivered most slowly and produced the smallest aerodynamic particle size of the RIS aerosols, which may be applied to manage lower respiratory diseases. Moreover, Pari LC Plus and Pari Boy SX (blue) emitted quickly and generated larger aerodynamic particle size of RIS aerosols, which could be used to treat upper respiratory diseases. A good linear relationship between MMAD and D₅₀ showed Spraytec could be a reliable technique for the development, evaluation and quality control of aerosol particles of inhalation solution preparations.

Delivery dose uniformity determination by BRS 2000 breath simulator and realtime particle size distribution monitoring by Spraytec.

Critical Parameters for Particle-Based Pulmonary Delivery of Chemotherapeutics

Targeted delivery of chemotherapeutics through the respiratory system is a potential approach to improve drug accumulation in the lung tumor, while decreasing their negative side effects. However, elimination by the pulmonary clearance mechanisms, including the mucociliary transport system, and ingestion by the alveolar macrophages, rapid absorption into the blood, enzymatic degradation, and low control over the deposition rate and location remain the main complications for achieving an effective pulmonary drug delivery. Therefore, particle-based delivery systems have emerged to minimize pulmonary clearance mechanisms, enhance drug therapeutic efficacy, and control the release behavior. A successful implementation of a particle-based delivery system requires understanding the influential parameters in terms of drug carrier, inhalation technology, and health status of the patient's respiratory system. This review aims at investigating the parameters that significantly drive the clinical outcomes of various particle-based pulmonary delivery systems. This should aid clinicians in appropriate selection of a delivery system according to their clinical setting. It will also guide researchers in addressing the remaining challenges that need to be overcome to enhance the efficiency of current pulmonary delivery systems for aerosols.

Surviving nebulization-induced stress: dexamethasone in pH-sensitive archaeosomes

Aim: To increase the subcellular delivery of dexamethasone phosphate (DP) and stability to nebulization stress, pH-sensitive nanoliposomes (LpH) exhibiting archaeolipids, acting as ligands for scavenger receptors (pH-sensitive archaeosomes [ApH]), were prepared. Materials & methods: The anti-inflammatory effect of 0.18 mg DP/mg total lipid, 100–150 nm DP-containing ApH (dioleylphosphatidylethanolamine: Halorubrum tebenquichense total polar archaeolipids:cholesteryl hemisuccinate 4.2:2.8:3 w:w) was tested on different cell lines. Size and HPTS retention of ApH and conventional LpH (dioleylphosphatidylethanolamine:cholesteryl hemisuccinate 7:3 w:w) before and after nebulization were determined. Results & conclusion: DP-ApH suppressed IL-6 and TNF-α on phagocytic cells. Nebulized after 6-month storage, LpH increased size and completely lost its HPTS while ApH3 conserved size and polydispersity, fully retaining its original HPTS content.