Inhalable sustained-release formulation of long-acting vasoactive intestinal peptide derivative alleviates acute airway inflammation

Long-acting inhaled medicines: Present and future

Inhaled medicines continue to be an essential part of treatment for respiratory diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. In addition, inhalation technology, which is an active area of research and innovation to deliver medications via the lung to the bloodstream, offers potential advantages such as rapid onset of action, enhanced bioavailability, and reduced side effects for local treatments. Certain inhaled macromolecules and particles can also end up in different organs via lymphatic transport from the respiratory epithelium. While the majority of research on inhaled medicines is focused on the delivery technology, particle engineering, combination therapies, innovations in inhaler devices, and digital health technologies, researchers are also exploring new pharmaceutical technologies and strategies to prolong the duration of action of inhaled drugs. This is because, in contrast to most inhaled medicines that exert a rapid onset and short duration of action, long-acting inhaled medicines (LAIM) improve not only the patient compliance by reducing the dosing frequency, but also the effectiveness and convenience of inhaled therapies to better manage patients' conditions. This paper reviews the advances in LAIM, the pharmaceutical technologies and strategies for developing LAIM, and emerging new inhaled modalities that possess a long-acting nature and potential in the treatment and prevention of various diseases. The challenges in the development of the future LAIM are also discussed where active research and innovations are taking place.

Inhaled nano-based therapeutics for inflammatory lung diseases: Recent advances and future prospects

Inflammatory lung diseases related morbidity and mortality impose a significant financial burden. Inflammation is a hallmark of many diseases of the respiratory system which is directly or indirectly linked to adverse health conditions, air pollution, rapid lifestyle changes, and regular outbreaks of microbial infections. The unique anatomical and physiological features of the lungs make them an ideal target organ in the treatment of inflammatory respiratory disease and with the help of inhaled therapy lungs can be targeted directly. The principal objective of this review is to present the comprehensive role of inhaled nano-based therapeutics such as liposomes, niosomes, nanoparticles, nanoemulsion, nanosuspension, and exosomes in the treatment and management of inflammatory respiratory diseases. Inhaled nanomedicines provide targeted diagnosis and treatment, improved drug solubility and distribution, prevent first-pass hepatic metabolism, improved patient compliance, and reduced drug side effects. They overcome several biological barriers in the human body and provide immediate, and quick-onset of action. Future research should be focused on improving the therapeutic efficiency of inhaled nanocarriers and to carry out in-depth mechanistic studies to translate current scientific knowledge for the efficient management of inflammatory lung diseases with minimal or no toxicity.

Vasoactive intestinal peptide overexpression mediated by lentivirus attenuates lipopolysaccharide-induced acute lung injury in mice by inhibiting inflammation

Vasoactive intestinal peptide (VIP) is one of the most abundant neuropeptides in the lungs with various biological characters. We have reported that VIP inhibited the expressions of TREM-1 and IL-17A, which are involved in the initiation and amplification of inflammation in acute lung injury (ALI). However, the overall effect of VIP on ALI remains unknown. The aim of this study is to investigate the therapeutic effect of VIP mediated by lentivirus (Lenti-VIP) on lipopolysaccharide (LPS)-induced murine ALI. We found that the expression of intrapulmonary VIP peaked at day7 after the intratracheal injection of Lenti-VIP. Lenti-VIP increased the respiratory rate, lung compliance, and tidal volume, while decreased airway resistance in ALI mice, detected by Buxco system. Lenti-VIP significantly reduced inflammatory cell infiltration and maintained the integrity of the alveolar septa. Lenti-VIP also remarkably decreased the total protein level, the number of neutrophil and lactate dehydrogenase activity in the bronchoalveolar lavage fluid of LPS-induced ALI mice. In addition, Lenti-VIP down-regulated pro-inflammatory tumor necrosis factor (TNF)-α mRNA and protein expression, while up-regulated anti-inflammatory interleukin-10 mRNA and protein expression in lungs of ALI mice. Furthermore, we observed that VIP reduced the TNF-α expression in murine macrophages under LPS stimulation through protein kinase C and protein kinase A pathways. Together, our findings show that in vivo administration of lentivirus expressing VIP exerts a potent therapeutic effect on LPS-induced ALI in mice via inhibiting inflammation.

Nanomedicines: current status and future perspectives in aspect of drug delivery and pharmacokinetics

Nanomedicines have evolved into various forms including dendrimers, nanocrystals, emulsions, liposomes, solid lipid nanoparticles, micelles, and polymeric nanoparticles since their first launch in the market. Widely highlighted benefits of nanomedicines over conventional medicines include superior efficacy, safety, physicochemical properties, and pharmacokinetic/pharmacodynamic profiles of pharmaceutical ingredients. Especially, various kinetic characteristics of nanomedicines in body are further influenced by their formulations. This review provides an updated understanding of nanomedicines with respect to delivery and pharmacokinetics. It describes the process and advantages of the nanomedicines approved by FDA and EMA. New FDA and EMA guidelines will also be discussed. Based on the analysis of recent guidelines and approved nanomedicines, key issues in the future development of nanomedicines will be addressed.

[Effects of vasoactive intestinal peptide on airway inflammation and Th17/Treg balance in asthmatic mice]

OBJECTIVE

To investigate the effects of vasoactive intestinal peptide (VIP) on the airway inflammation and its regulatory effect on Th17/Treg imbalance in asthmatic mice.

METHODS

A total of 30 BALB/c mice were equally and randomly divided into three groups: control, asthma, and VIP. An acute asthmatic mouse model was established by sensitization and challenge with ovalbumin (OVA). The control group received normal saline instead of OVA. Before the challenge with OVA, the VIP group was administered VIP (20 μg/mL) by aerosol inhalation for 30 minutes. The bronchoalveolar lavage fluid (BALF) and the lung tissue were collected from mice. The pathological changes in the lung tissue were observed by hematoxylin and eosin staining. The levels of Th17/Treg-related cytokines in BALF were measured by enzyme-linked immunosorbent assay. The expression of retinoid-related orphan receptor gamma t (RORγt) and forkhead box P3 (Foxp3) were measured by real-time fluorescence quantitative PCR and immunohistochemistry.

RESULTS

The histopathological results showed that the VIP group had milder symptoms of airway inflammation than the asthma group. The level of IL-17 in BALF in the asthma group was significantly higher than that in the control group and the VIP group (P<0.01), but the level of IL-17 in the control group was significantly lower than that in the VIP group (P<0.01). The level of IL-10 in BALF in the asthma group was significantly lower than that in the control group and the VIP group (P<0.01, but the level of IL-10 in the VIP group was significantly higher than that in the control group (P<0.01). The asthma group showed significantly higher expression levels of RORγt mRNA and protein in the lung tissue and significantly lower expression levels of Foxp3 mRNA and protein than the control group (P<0.01). The VIP group had significantly lower expression levels of RORγt mRNA and protein in the lung tissue and significantly higher expression levels of Foxp3 mRNA and protein than the asthma group (P<0.05).

CONCLUSIONS

The Th17/Treg imbalance may be closely related to the airway inflammation in asthmatic mice. VIP can improve airway inflammation by regulating the Th17/Treg imbalance in asthmatic mice.

Low-Molecular-Weight Heparin-Coated and Montelukast-Filled Inhalable Particles: A Dual-Drug Delivery System for Combination Therapy in Asthma

Montelukast, a cysteinyl leukotriene type 1 receptor antagonist, exhibits secondary anti-inflammatory properties when used at higher concentrations. Low-molecular-weight heparin (LMWH) evokes pronounced anti-inflammatory effects by interrupting leukocyte adhesion and migration. We hypothesized that inhalable particles containing montelukast plus LMWH release both drugs in a sustained fashion and protect the lungs against allergen-induced inflammation. Large porous particles of montelukast and LMWH were prepared using a double-emulsion-solvent-evaporation method. Montelukast was first encapsulated in copolymer-based particles using polyethylenimine as a porosigen; the resulting particles were then coated with LMWH. The particles were evaluated for physicochemical properties, respirability, and release profiles. The anti-inflammatory effect of the optimized formulation was studied in ovalbumin-sensitized asthmatic Sprague Dawley rats. The optimized large porous particles had a diameter of 10.3 ± 0.7 μm, exhibited numerous surface indentations and pores, showed acceptable drug entrapment efficiency (66.8% ± 0.4% for montelukast; 91.7% ± 0.8% adsorption efficiency for LMWH), demonstrated biphasic release patterns, and escaped the uptake by the rat alveolar macrophages. The number of infiltrating inflammatory cells in asthmatic rat lungs, treated with dual-drug particles, was >74% fewer than in untreated asthmatic rat lungs. Similarly, the airway walls of asthmatic animals treated with dual-drug particles were 3-fold thinner than those of untreated asthmatic animals (p < 0.001). The optimized formulation protects lungs against methacholine-induced airway hyper-reactivity. Overall, this study demonstrates the feasibility of loading 2 drugs, montelukast and LMWH, into an inhalable particulate system and establishes that this novel combination therapy produces sustained drug release and elicits a robust anti-inflammatory response in the lungs.

Conjugated Alpha-Alumina nanoparticle with vasoactive intestinal peptide as a Nano-drug in treatment of allergic asthma in mice

Asthma is a chronic respiratory disease characterized by airway inflammation, bronchoconstriction, airway hyperresponsiveness and recurring attacks of impaired breathing. Vasoactive intestinal peptide (VIP) has been proposed as a novel anti-asthma drug due to its effects on airway smooth muscle relaxation, bronchodilation and vasodilation along with its immunomodulatory and anti-inflammatory properties. In the current study, we investigated the therapeutic effects of VIP when conjugated with α-alumina nanoparticle (α-AN) to prevent enzymatic degradation of VIP in the respiratory tract. VIP was conjugated with α-AN. Balb/c mice were sensitized and challenges with ovalbumin (OVA) or PBS and were divided in four groups; VIP-treated, α-AN-treated, α-AN-VIP-treated and beclomethasone-treated as a positive control group. Specific and total IgE level, airway hyperresponsiveness (AHR), bronchial cytokine expression and lung histology were measured. α-AN-VIP significantly reduced the number of eosinophils (Eos), serum IgE level, Th2 cytokines and AHR. These effects of α-AN-VIP were more pronounced than that seen with beclomethasone or VIP alone (P<0.05). The current data indicate that α-AN-VIP can be considered as an effective nano-drug for the treatment of asthma.

Augmentation of the effects of vasoactive intestinal peptide aerosol on pulmonary hypertension via coapplication of a neutral endopeptidase 24.11 inhibitor

A deficiency of the pulmonary vasodilative vasoactive intestinal peptide (VIP) has been suggested to be involved in the pathophysiology of pulmonary hypertension (PH). Supplementation of VIP as an aerosol is hampered by the fact that it is rapidly inactivated by neutral endopeptidases (NEP) located on the lung surface. Coapplication of thiorphan, an NEP 24.11 inhibitor, could augment the biological effects of inhaled VIP alone. A stable pulmonary vasoconstriction with a threefold increase of pulmonary artery pressure was established by application the thromboxane mimetic U46619 in the isolated rabbit lung model. VIP and thiorphan were either applied intravascularly or as an aerosol. VIP caused a significant pulmonary vasodilation either during intravascular application or inhalation. These effects were of short duration. Thiorphan application had no effects on pulmonary vasoconstriction per se but significantly augmented the effects of VIP aerosol. Thiorphan, not only augmented the maximum hemodynamic effects of VIP aerosol, but also led to a significant prolongation of these effects. VIP causes pulmonary vasodilation in a model of acute experimental PH. The hemodynamic effects of VIP aerosol can be significantly augmented via coapplication of an NEP inhibitor.

Role of VPAC2 receptor in monocrotaline-induced pulmonary hypertension in rats

Pulmonary hypertension (PH) is associated with significant morbidity and mortality. Vasoactive intestinal peptide (VIP) and pituitary adenylyl cyclase activating peptide (PACAP) have pulmonary vasodilatory and positive inotropic effects via receptors VPAC1 and VPAC2, which possess a similar affinity for both peptides, and PAC1, a PACAP-preferring receptor. VIP is a promising option for PH treatment; however, various physiological effects of VIP have limited its clinical use. We investigated the effects of VPAC1 and VPAC2 selective agonists VIP and PACAP to explore more appropriate means of treatment for PH. We examined hemodynamic changes in right ventricular systolic pressure (RVSP), systemic blood pressure (SBP), total pulmonary resistance index (TPRI), total systemic resistance index, and cardiac index (CI) in response to their agonists with monocrotaline (MCT)-induced PH and explored involvement of VIP/PACAP expression and receptors in PH. Sprague-Dawley rats were divided into the MCT group (administered MCT 60 mg/kg) and control group. In MCT-induced PH, decreased VIP and PACAP were associated with upregulation of VPAC1, VPAC2, and PAC1 in lung tissues. Intravenous injection of VPAC2-selective agonist BAY 55-9837 and VIP, but not [Ala(11,22,28)]VIP, improved the CI. The decrease in SBP with VPAC2 agonist was significantly less than that in the control. Although they decreased SBP, these agonists hardly affected RVSP in the control. Activation of VPAC2 receptor with BAY 55-9837 effectively improved RVSP, TPRI, and CI in MCT-induced PH, suggesting a VPAC2 agonist as a possible promising treatment for PH.

Aerosolized montelukast polymeric particles-an alternative to oral montelukast-alleviate symptoms of asthma in a rodent model

PURPOSE

Cysteinyl leukotrienes (CysLTs) propagate inflammatory reactions that result from allergen exposure in asthma. Montelukast, a CysLT type-1 receptor antagonist, disrupts mediator-receptor interactions and minimizes inflammatory response. In this study, we have evaluated anti-asthmatic efficacy of inhalable montelukast-loaded large porous particulate formulations in ovalbumin-induced rat airway inflammation model that mimics asthma.

METHODS

The anti-inflammatory effects of a montelukast-loaded formulation were investigated in rats by measuring the total protein content, levels of injury markers and number of inflammatory cells in the bronchoalveolar lavage fluid (BALF). The histopathological studies assessed the morphological and structural changes that occur in asthmatic lungs. Animals were also challenged with methacholine to examine the airway hyper-reactivity.

RESULTS

Compared with healthy animals, asthmatic animals showed a 3.8- and 4.77-fold increase in the protein content and number of inflammatory cells in BALF, respectively. Intratracheal montelukast particles reduced the protein content by 3.3-fold and the number of inflammatory cells by 2.62-fold. Also, montelukast particles reduced the lactate dehydrogenase (LDH) and myeloperoxidase (MPO) levels by a 4.87- and 6.8-fold in BALF, respectively. Montelukast particles reduced the airway wall thickness by 2.5-fold compared with untreated asthmatic lungs. Further, particulate formulation protected the lungs against methacholine-induced bronchial provocation (p < 0.05).

CONCLUSIONS

Respirable large porous particles containing montelukast alleviated allergen-induced inflammatory response in an animal model and prevented histological changes associated with asthma. Thus montelukast-loaded large porous polylactic acid (PLA) particles could be an aerosolized delivery approach for administration of currently available oral montelukast.

Nanodrugs: pharmacokinetics and safety

To date, various nanodrug systems have been developed for different routes of administration, which include dendrimers, nanocrystals, emulsions, liposomes, solid lipid nanoparticles, micelles, and polymeric nanoparticles. Nanodrug systems have been employed to improve the efficacy, safety, physicochemical properties, and pharmacokinetic/pharmacodynamic profile of pharmaceutical substances. In particular, functionalized nanodrug systems can offer enhanced bioavailability of orally taken drugs, prolonged half-life of injected drugs (by reducing immunogenicity), and targeted delivery to specific tissues. Thus, nanodrug systems might lower the frequency of administration while providing maximized pharmacological effects and minimized systemic side effects, possibly leading to better therapeutic compliance and clinical outcomes. In spite of these attractive pharmacokinetic advantages, recent attention has been drawn to the toxic potential of nanodrugs since they often exhibit in vitro and in vivo cytotoxicity, oxidative stress, inflammation, and genotoxicity. A better understanding of the pharmacokinetic and safety characteristics of nanodrugs and the limitations of each delivery option is necessary for the further development of efficacious nanodrugs with high therapeutic potential and a wide safety margin. This review highlights the recent progress in nanodrug system development, with a focus on the pharmacokinetic advantages and safety challenges.

T regulatory cells in childhood arthritis--novel insights

In recent years, there have been many new developments in the field of regulatory T cells (Treg), challenging the consensus on their behaviour, classification and role(s) in disease. The role Treg might play in autoimmune disease appears to be more complex than previously thought. Here, we discuss the current knowledge of regulatory T cells through animal and human research and illustrate the recent developments in childhood autoimmune arthritis (juvenile idiopathic arthritis (JIA)). Furthermore, this review summarises our understanding of the fields and assesses current and future implications for Treg in the treatment of JIA.

Low-molecular-weight heparin (LMWH)-loaded large porous PEG-PLGA particles for the treatment of asthma

BACKGROUND

Heparin-like compounds interrupt leukocyte adhesion and migration, and prevent release of chemical mediators during the process of inflammation. However, little is known whether the anti-inflammatory property of smaller heparin fragments, low-molecular-weight heparin (LMWH), plays any role in the process of airway inflammation. In this study, we sought to evaluate the efficacy of LMWH-loaded large porous polyethylene glycol-poly(D,L-lactide-co-glycolide) (PEG-PLGA) particulate formulations in alleviating the cellular and biochemical changes associated with asthma.

METHODS

To study the pharmacological efficacy of LMWH for the treatment of asthma, we have used a previously optimized polymeric formulation of LMWH. The anti-asthmatic efficacy of the optimized formulation was studied in an ovalbumin-sensitized rat model of asthma. The influence of the formulation on asthmatic lungs was assessed by measuring the total protein content and number of inflammatory cells in the bronchoalveolar lavage fluid (BALF). Lungs were also examined for morphological and structural changes that may occur in asthmatic lungs.

RESULTS

Compared with healthy animals, asthmatic animals showed a seven- and threefold increase in the protein content and number of inflammatory cells in BALF, respectively. However, intratracheal LMWH particles reduced the protein content by 2.5-fold and the number of inflammatory cells by 1.8-fold-comparable to those of sham animals. Similarly, LMWH particles reduced the lactate dehydrogenase levels by 2.8- and threefold in BALF and plasma, respectively. The airway wall thickness also decreased from 47.37±6.02 μm to 21.35±3.60 μm upon treatment with PEG-PLGA particles of LMWH. Goblet cell hyperplasia was also reduced in asthmatic rats treated with LMWH particles.

CONCLUSION

PLGA particles of LMWH were efficacious in improving cellular and histological changes associated with asthma, and thus this polymeric formulation has the potential for further development into a clinically viable anti-asthma therapy.