Isothiocyanate-Corticosteroid Conjugates against asthma: Unity makes strength.

Asthma is a major noncommunicable disease, affecting both children and adults, and represents one of the major causes leading to high health care costs due to the need for chronic pharmacological treatments. The standard gold therapy of inflammation in asthmatic patients involves the use of glucocorticoids even if their chronic use is often related to serious adverse effects. Growing evidence suggests the biological relevance of hydrogen sulfide (H2S) in the pathogenesis of airway diseases. Hence, aiming to associate the beneficial effects of steroidal anti-inflammatory drugs (SAIDs) to H2S biological activity, we designed and synthesized novel multi-target molecules by chemically combining a group of glucocorticoids, usually employed in asthma treatment, with an isothiocyanate moiety, well-known for its H2S releasing properties. Firstly, the synthesized compounds have been screened for their H2S-releasing profile using an amperometric approach and for their in vitro effects on the degranulation process, using RBL-2H3 cell line. The physicochemical profile, in terms of solubility, chemical and enzymatic stability of the newly hybrid molecules, has been assessed at different physiological pH values and in esterase-rich medium (bovine serum albumin, BSA). The selected compound 5c, through both its corticosteroid and H2S releasing component, has been evaluated in vivo in experimental model of asthma. The compound 5c inhibited in vivo all asthma features with a significative effect on the restoration of pulmonary structure and reduction of lung inflammation.

Involvement of porcine and human carbonyl reductases in the metabolism of epiandrosterone, 11-oxygenated steroids, neurosteroids, and corticosteroids.

Porcine carbonyl reductases (pCBR1 and pCBR-N1) and aldo-keto reductases (pAKR1C1 and pAKR1C4) exhibit hydroxysteroid dehydrogenase (HSD) activity. However, their roles in the metabolism of porcine-specific androgens (19-nortestosterone and epiandrosterone), 11-oxygenated androgens, neurosteroids, and corticosteroids remain unclear. Here, we compared the steroid specificity of the four recombinant enzymes by kinetic and product analyses. In C18/C19-steroids,11-keto- and 11ß-hydroxy-5α-androstane-3,17-diones were reduced by all the enzymes, whereas 5α-dihydronandrolone (19-nortestosterone metabolite) and 11-ketodihydrotestosterone were reduced by pCBR1, pCBR-N1, and pAKR1C1, of which pCBR1 exhibited the lowest (submicromolar) Km values. Product analysis showed that pCBR1 and pCBR-N1 function as 3α/ß-HSDs, in contrast to pAKR1C1 and pAKR1C4 (acting as 3ß-HSD and 3α-HSD, respectively). Additionally, 17ß-HSD activity was observed in pCBR1 and pCBR-N1 (toward epiandrosterone and its 11-oxygenated derivatives) and in pAKR1C1 (toward androsterone, 4-androstene-3,17-dione and their 11-oxygenated derivatives). The four enzymes also showed different substrate specificity for 3-keto-5α/ß-dihydro-C21-steroids, including GABAergic neurosteroid precursors and corticosteroid metabolites. 5ß-Dihydroprogesterone was reduced by all the enzymes, whereas 5α-dihydroprogesterone was reduced only by pCBR1, and 5α/ß-dihydrodeoxycorticosterones by pCBR1 and pCBR-N1. The two pCBRs also reduced the 5α/ß-dihydro-metabolites of cortisol, 11-deoxycortisol, cortisone, and corticosterone. pCBR1 exhibited lower Km values (0.3-2.9 µM) for the 3-keto-C21-steroids than pCBR-N1 (Km=10-36 µM). The reduced products of the 3-keto-C21-steroids by pCBR1 and pCBR-N1 were their 3α-hydroxy-metabolites. Finally, we found that human CBR1 has similar substrate specificity for the C18/C19/C21-steroids to pCBR-N1. Based on these results, it was concluded that porcine and human CBRs can be involved in the metabolism of the aforementioned steroids as 3α/ß,17ß-HSDs.

Structural biology of SARS-CoV-2: open the door for novel therapies.

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the causative agent of the pandemic disease COVID-19, which is so far without efficacious treatment. The discovery of therapy reagents for treating COVID-19 are urgently needed, and the structures of the potential drug-target proteins in the viral life cycle are particularly important. SARS-CoV-2, a member of the Orthocoronavirinae subfamily containing the largest RNA genome, encodes 29 proteins including nonstructural, structural and accessory proteins which are involved in viral adsorption, entry and uncoating, nucleic acid replication and transcription, assembly and release, etc. These proteins individually act as a partner of the replication machinery or involved in forming the complexes with host cellular factors to participate in the essential physiological activities. This review summarizes the representative structures and typically potential therapy agents that target SARS-CoV-2 or some critical proteins for viral pathogenesis, providing insights into the mechanisms underlying viral infection, prevention of infection, and treatment. Indeed, these studies open the door for COVID therapies, leading to ways to prevent and treat COVID-19, especially, treatment of the disease caused by the viral variants are imperative.

Synthetic corticosteroids as tryptophan hydroxylase stabilizers.

Background: Clinically, corticosteroids are used mainly for their immune-modulatory properties but are also known to influence mood. Despite evidence of a role in regulating tryptophan hydroxylases (TPH), key enzymes in serotonin biosynthesis, a direct action of corticosteroids on these enzymes has not been systematically investigated. Methodology & results: Corticosteroid effects on TPHs were tested using an in vitro assay. The compound with the strongest modulatory effect, beclomethasone dipropionate, activated TPH1 and TPH2 with low micromolar potency. Thermostability assays suggested a stabilizing mechanism, and computational docking indicated that beclomethasone dipropionate interacts with the TPH active site. Conclusion: Beclomethasone dipropionate is a stabilizer of TPHs, acting as a pharmacological chaperone. Our findings may inspire further development of steroid scaffolds as putative antidepressant drugs.

Synthetic approaches to FDA approved drugs for asthma and COPD from 1969 to 2020.

Respiratory infections resulting from pulmonary inflammation emerging as a leading cause of death worldwide. However, only twenty-seven new drugs were approved in the last five decades. In this review, we presented synthetic approaches for twenty-seven FDA-approved medications used to treat asthma and chronic obstructive pulmonary diseases (COPD), along with their mode of action.

Polymer-free corticosteroid dimer implants for controlled and sustained drug delivery.

Polymeric drug carriers are widely used for providing temporal and/or spatial control of drug delivery, with corticosteroids being one class of drugs that have benefitted from their use for the treatment of inflammatory-mediated conditions. However, these polymer-based systems often have limited drug-loading capacity, suboptimal release kinetics, and/or promote adverse inflammatory responses. This manuscript investigates and describes a strategy for achieving controlled delivery of corticosteroids, based on a discovery that low molecular weight corticosteroid dimers can be processed into drug delivery implant materials using a broad range of established fabrication methods, without the use of polymers or excipients. These implants undergo surface erosion, achieving tightly controlled and reproducible drug release kinetics in vitro. As an example, when used as ocular implants in rats, a dexamethasone dimer implant is shown to effectively inhibit inflammation induced by lipopolysaccharide. In a rabbit model, dexamethasone dimer intravitreal implants demonstrate predictable pharmacokinetics and significantly extend drug release duration and efficacy (>6 months) compared to a leading commercial polymeric dexamethasone-releasing implant.

Corticosteroids and cellulose purification improve, respectively, the in vivo translation and vaccination efficacy of sa-mRNAs.

Synthetic mRNAs are an appealing platform with multiple biomedical applications ranging from protein replacement therapy to vaccination. In comparison with conventional mRNA, synthetic self-amplifying mRNAs (sa-mRNAs) are gaining interest because of their higher and longer-lasting expression. However, sa-mRNAs also elicit an innate immune response, which may complicate their clinical application. Approaches to reduce the innate immunity of sa-mRNAs have not been studied in detail. Here we investigated, in vivo, the effect of several innate immune inhibitors and a novel cellulose-based mRNA purification approach on the type I interferon (IFN) response and the translation and vaccination efficacy of our formerly developed sa-mRNA vaccine against Zika virus. Among the investigated inhibitors, we found that corticosteroids and especially topical application of clobetasol at the sa-mRNA injection site was the most efficient in suppressing the type I IFN response and increasing the translation of sa-mRNA. However, clobetasol prevented formation of antibodies against sa-mRNA-encoded antigens and should therefore be avoided in a vaccination context. Residual dsRNA by-products of the in vitro transcription reaction are known inducers of immediate type I IFN responses. We additionally demonstrate a drastic reduction of these dsRNA by-products upon cellulose-based purification, reducing the innate immune response and improving sa-mRNA vaccination efficacy.

Topical corticosteroid vehicle composition and implications for clinical practice.

This narrative review highlights the therapeutic significance of topical corticosteroid (TCS) vehicles and provides subsequent guidance to improve clinical and research outcomes. A greater understanding of the relationship between the topical vehicle, corticosteroid and skin is needed to ensure safer, more effective treatment for patients. Topical vehicles are not inert and can affect TCS bioavailability, due to the ability of their composition to positively or negatively influence skin status and change the physiochemical characteristics of an inherent corticosteroid. However, this principle is not commonly understood, and has contributed to inconsistencies in potency classification systems. This review provides an insight into the research methods and standardization needed to determine TCS product bioavailability. It identifies formulation components responsible for vehicle composition that underpin the quality, stability, compounding and functionalities of vehicle ingredients. This helps to contextualize how topical vehicles can be responsible for clinically significant effects, and how their composition gives products unique properties. In turn, this facilitates a more in-depth understanding of which resources offer information to inform the best selection of TCS products and why products should be prescribed by brand or manufacturer. This review will better equip clinicians and formulary teams to appraise products. It will also inform prescribing of Specials and why products should not be manipulated. The recommendations, accompanied by patient perspectives on using TCS products, assist clinical decision-making. They also identify the need for research into concomitant application of TCS products with other topical therapies.

Orally Inhaled Drug Particle Transport in Computerized Models of Laryngotracheal Stenosis.

OBJECTIVE: Adjuvant management for laryngotracheal stenosis (LTS) may involve inhaled corticosteroids, but metered dose inhalers are designed for pulmonary drug delivery. Comprehensive analyses of drug particle deposition efficiency for orally inhaled corticosteroids in the stenosis of LTS subjects are lacking. STUDY DESIGN: Descriptive research. SETTING: Academic medical center. METHODS: Anatomically realistic 3-dimensional reconstructions of the upper airway were created from computed tomography images of 4 LTS subjects-2 subglottic stenosis and 2 tracheal stenosis subjects. Computational fluid dynamics modeling was used to simulate airflow and drug particle transport in each airway. Three inhalation pressures were simulated, 10 Pa, 25 Pa, and 40 Pa. Drug particle transport was simulated for 100 to 950 nanoparticles and 1 to 50 micron-particles. Particles were released into the airway to mimic varying inhaler conditions with and without a spacer chamber. RESULTS: Based on smallest to largest cross-sectional area ratio, the laryngotracheal stenotic segment shrunk by 57% and 47%, respectively, for subglottic stenosis models and by 53% for both tracheal stenosis models. Airflow resistance at the stenotic segment was lower in subglottic stenosis models than in tracheal stenosis models: 0.001 to 0.011 Pa.s/mL vs 0.024 to 0.082 Pa.s/mL. Drug depositions for micron-particles and nanoparticles at stenosis were 0.06% to 2.48% and 0.10% to 2.60% for subglottic stenosis and tracheal stenosis models, respectively. Particle sizes with highest stenotic deposition were 6 to 20 µm for subglottic stenosis models and 1 to 10 µm for tracheal stenosis models. CONCLUSION: This study suggests that at most, 2.60% of inhaled drug particles deposit at the stenosis. Particle size ranges with highest stenotic deposition may not represent typical sizes emitted by inhalers.

Is the unique benzodiazepine structure interacting with CYP enzymes to affect steroid synthesis in vitro?

The aim of this project was to investigate the endocrine disrupting effects of three γ-aminobutyric acid type A receptor (GABAAR) agonists, diazepam (DZ), oxazepam (OX) and alprazolam (AL) using the steroidogenic in vitro H295R cell line assay, a recombinant CYP17A1 assay, qPCR analysis and computational modelling. Similar effects for DZ and OX on the steroidogenesis were observed in the H295R experiment at therapeutically relevant concentrations. Progestagens and corticosteroids were increased up to 10 fold and androgens were decreased indicating CYP17A1 lyase inhibition. For DZ the inhibition on both the hydroxylase and lyase was confirmed by the recombinant CYP17A1 assay, whereas OX did not appear to directly affect the recombinant CYP17A1 enzyme. Androgens were decreased when exposing the H295R cells to AL, indicating a CYP17A1 lyase inhibition. However, this was not confirmed by the recombinant CYP17A1 assay but a down-regulation in gene expression was observed for StAR and CYP17A1. The present study showed that the three investigated benzodiazepines (BZDs) are rather potent endocrine disruptors in vitro, exerting endocrine effects close the therapeutic Cmax. Both direct and indirect effects on steroidogenesis were observed, but molecular modelling indicated no direct interactions between the heme group in the steroidogenic CYP enzymes and the unique diazepin structure. In contrast, physicochemical properties such as high log P, structure and molecular weight similar to that of steroids appeared to influence the endocrine disrupting abilities of the investigated pharmaceuticals in vitro. Docking of the three BZDs in CYP17A1 and CYP21A2 confirmed that shape complementarity and hydrophobic effects seem to determine the binding modes.

Supramolecular aggregates of cyclodextrins with co-solvent modulate drug dispersion and release behavior of poorly soluble corticosteroid from chitosan membranes.

In this study, the ability of different beta-cyclodextrins to facilitate homogeneous dispersion of triamcinolone acetonide (TA) into chitosan membranes is assessed. Drug loading was assessed through atomic force microscopy (AFM), scanning electron microscopy (MEV-FEG), and X-ray diffraction analyses. Drug interactions with the co-polymer were investigated with Fourier transform infrared spectroscopy, thermal analyses. Swelling assay, and in vitro drug release experiment were used to assess TA release behavior. Undispersed particles of drug were observed to remain in the simple chitosan membranes. Hydroxypropyl-ß-cyclodextrin enabled the dispersion of TA into chitosan membranes and subsequent sustained drug release. In addition, the membrane performance as a drug delivery device is improved by adding specified amounts of the co-solvent triethanolamine. The experimental data presented in this study confirm the utility of our novel and alternative approach for obtaining a promising device for slow and controlled release of glucocorticoids, such as triamcinolone acetonide, for topical ulcerations.

Recent Approaches on Novel Topical Delivery Systems for Atopic Dermatitis Treatment.

Atopic dermatitis is a chronic inflammatory disease of the skin, which is characterized by itching, erythema, and eczematous lacerations. It affects about 10 % of adults and approximately 15-20 % of children worldwide. As a result of genetic, immunologic, and environmental factors, the disease manifests itself with the impaired stratum corneum barrier and then immunological responses. Topical administration of corticosteroids and calcineurin inhibitors are currently used as the first strategy in the management of the disease. However, they have low skin bioavailability and some side effects. The nanocarriers as novel drug delivery systems could overcome limitations of conventional dosage forms, owing to increment of poorly soluble drug' solubility, then its thermodynamic activity and, consequently, its skin permeation. Also, side effects of the drug substances on the skin could be reduced by the nano-sized drug delivery systems due to encapsulation of the drug in the nanocarriers and targeted drug delivery of drug substances to the inflammated skin areas. Thereby, there have been available numerous research studies and patents regarding the use of nanocarriers in the management of atopic dermatitis. This review focuses on the mechanism of disease and development of nanocarrier based on novel drug release systems in the management of atopic dermatitis.

Targeted Therapies for Eosinophilic Gastrointestinal Disorders.

The growing recognition of eosinophilic gastrointestinal disorders has revealed the limitations of current treatment (mainly based on dietary modification and corticosteroids), and include refractoriness, high recurrence rates, and the need for long-term therapy. Research efforts, mainly in eosinophilic esophagitis (EoE), have unveiled essential pathophysiological mechanisms leading to these disorders, which bear some similarities to those of atopic manifestations and are shared by eosinophilic gastroenteritis (EGE) and eosinophilic colitis (EC). Novel targeted therapies, some imported from bronchial asthma and atopic dermatitis, are currently being assessed in EoE. The most promising are monoclonal antibodies, including those targeting interleukin (IL)-13 (cendakimab) and IL-4 (dupilumab), with phase 3 trials currently ongoing. The potential of anti-integrin therapy (vedolizumab) and Siglec-8 blockers (antolimab) in EGE are also promising. Non-biological therapies for eosinophilic gut disorders, which include preventing the activation of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and chemoattractant receptor expressed on T helper 2 cells (CRTH2) signaling pathways, and other potential targets that deserve investigation in eosinophilic gut disorders, are reviewed.

Development of an Aerosol Dose Collection Apparatus for In Vitro Dissolution Measurements of Orally Inhaled Drug Products.

The aim of the study was to develop a robust and standardized in vitro dissolution methodology for orally inhaled drug products (OIDPs). An aerosol dose collection (ADC) system was designed to uniformly deposit the whole impactor stage mass (ISM) over a large filter area for dissolution testing. All dissolution tests were performed under sink conditions in a sodium phosphate buffered saline solution containing 0.2%w/w sodium dodecyl sulphate. An adapted USP Apparatus V, Paddle over Disk (POD), was used throughout the study. The dissolution characteristics of the ISM dose of a commercial metered-dose inhaler (MDI) and a range of dry powder inhaler (DPI) formulations containing inhaled corticosteroids were tested. The uniform distribution of the validated ISM dose considerably reduced drug loading effects on the dissolution profiles for both MDI and DPI formulations. The improvement in the robustness and discriminatory capability of the technique enabled characterization of dissolution rate differences between inhaler platforms and between different DPI product strengths containing fluticasone propionate. A good correlation between in vivo mean absorption time and in vitro dissolution half-life was found for a range of the inhaled corticosteroids. The ADC system and the reproducible in vitro POD dissolution measurements provided a quantitative-based approach for measuring the relationship between the influence of device and the dispersion characteristics on the aerosol dissolution of low solubility compounds. The in vitro dissolution method could potentially be applied as a dissolution methodology for compendial, quality control release testing, and during development of both branded orally inhaled drug products and their generic counterparts.

Biologicals in the Treatment of Pediatric Atopic Diseases.

The management of atopic diseases such as severe asthma, severe atopic dermatitis, and severe food allergy in childhood is challenging. In particular, there are safety concerns regarding the use of high-dose corticosteroids. The recent development of biologicals and their approval for the treatment of children offer a new, very promising, and more personalized therapy option. Omalizumab, mepolizumab, and dupilumab are currently approved as add-on treatments of severe asthma in children and have been shown to be effective in improvement of asthma control and reduction of exacerbations. Dupilumab is the only biological approved for the treatment of atopic dermatitis in adolescents so far. It has been demonstrated to significantly improve symptoms of atopic dermatitis.However, safety data for biologicals used in atopic diseases in children and adolescents are still very limited. Biologicals are generally considered to be safe in adults. These data are often extrapolated to children. Additionally, data for long-term use are lacking. Thus, the safety profiles of those biologicals cannot yet be conclusively assessed.

Glucocorticoid receptors signaling impairment potentiates amyloid-ß oligomers-induced pathology in an acute model of Alzheimer's disease.

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis occurs early in Alzheimer's disease (AD), associated with elevated circulating glucocorticoids (GC) and glucocorticoid receptors (GR) signaling impairment. However, the precise role of GR in the pathophysiology of AD remains unclear. Using an acute model of AD induced by the intracerebroventricular injection of amyloid-ß oligomers (oAß), we analyzed cellular and behavioral hallmarks of AD, GR signaling pathways, processing of amyloid precursor protein, and enzymes involved in Tau phosphorylation. We focused on the prefrontal cortex (PFC), particularly rich in GR, early altered in AD and involved in HPA axis control and cognitive functions. We found that oAß impaired cognitive and emotional behaviors, increased plasma GC levels, synaptic deficits, apoptosis and neuroinflammatory processes. Moreover, oAß potentiated the amyloidogenic pathway and enzymes involved both in Tau hyperphosphorylation and GR activation. Treatment with a selective GR modulator (sGRm) normalized plasma GC levels and all behavioral and biochemical parameters analyzed. GR seems to occupy a central position in the pathophysiology of AD. Deregulation of the HPA axis and a feed-forward effect on PFC GR sensitivity could participate in the etiology of AD, in perturbing Aß and Tau homeostasis. These results also reinforce the therapeutic potential of sGRm in AD.

Dilution and microfiltration of particulate corticosteroids for spinal epidural injections: impact on drug concentration and agglomerate formation.

Particulate corticosteroids have been described to lead to greater pain improvement compared with their non-particulate counterparts when used in epidural injections. It is hypothesised that filtering may significantly impact their concentration and long-term efficacy. We investigated if passing particulate suspensions through different commonly-used filters affects drug dosage. Two particulate corticosteroid formulations, triamcinolone acetonide and methylprednisolone acetate, were mixed at different concentrations with either bupivacaine hydrochloride or 0.9% sodium chloride. Solutions were passed through a 5-µm and a 0.2-µm filter. Mass spectroscopy results indicated a complete loss of corticosteroid from the solutions using both filters, and light microscopy imaging demonstrated agglomerate formation, suggesting that filtering interferes with drug dosage. The choice of diluents must also be considered to reduce large agglomerate formation. Clinicians should be aware of the consequences of filtering particulate suspensions and carefully consider the selection of diluent when considering treatment plans.