Breast density in NF1 women: a retrospective study

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition caused by neurofibromin haploinsufficiency due to pathogenic variants in the NF1 gene. Tumor predisposition has long been associated with NF1, and an increased breast cancer (BC) incidence and reduced survival have been reported in recent years for women with NF1. As breast density is another known independent risk factor for BC, this study aims to evaluate the variability of breast density in patients with NF1 compared to the general population. Mammograms from 98 NF1 women affected by NF1, and enrolled onto our monocentric BC screening program, were compared with those from 300 healthy subjects to verify differences in breast density. Mammograms were independently reviewed and scored by a radiologist and using a Computer-Aided Detection (CAD) software. The comparison of breast density between NF1 patients and controls was performed through Chi-squared test and with multivariable ordinal logistic models adjusted for age, body mass index (BMI), number of pregnancies, and menopausal status.breast density was influenced by BMI and menopausal status in both NF1 patients and healthy subjects. No difference in breast density was observed between NF1 patients and the healthy female population, even after considering the potential confounding factors.Although NF1 and a highly fibroglandular breast are known risk factors of BC, in this study, NF1 patients were shown to have comparable breast density to healthy subjects. The presence of pathogenic variants in the NF1 gene does not influence the breast density value.

The pharmacological management of asthma in adults: 2023 update

INTRODUCTION

The pharmacotherapy of asthma is a dynamic process that changes as our knowledge of the underlying pathophysiology and treatment of this disease continues to evolve. This implies the need for continuous revision of the recommendations of asthma guidelines and strategies.

AREAS COVERED

This review summarizes the latest key practical information on the pharmacological management of asthma in adults. We provide the background to the 2023 update of the GINA strategy report, focusing on changes and discussing areas of uncertainty. We review current and emerging pharmacotherapy for uncontrolled asthma, including synthetic agents and new biologics, and provide expert perspectives and opinions on the treatment of uncontrolled asthma.

EXPERT OPINION

The current pharmacological treatment of asthma, based on a step-by-step, control-based approach, with ICSs, LABAs and LAMAs being the mainstay generally provides good symptom control. Biologic therapies are often effective in treating T2high severe asthma. However, there is still room for improvement, such as the discovery of new molecules that specifically target chronic inflammation and, most importantly, the ability to provide solutions to the various areas of uncertainty that still exist. Also finding solutions to improve the accessibility and affordability of rescue ICS in resource-constrained settings is critical.

The effect of combining an inhaled corticosteroid and a long-acting muscarinic antagonist on human airway epithelial cells in vitro

BACKGROUND

Airway epithelial cells (AECs) are a major component of local airway immune responses. Direct effects of type 2 cytokines on AECs are implicated in type 2 asthma, which is driven by epithelial-derived cytokines and leads to airway obstruction. However, evidence suggests that restoring epithelial health may attenuate asthmatic features.

METHODS

We investigated the effects of passive sensitisation on IL-5, NF-κB, HDAC-2, ACh, and ChAT in human bronchial epithelial cells (HBEpCs) and the effects of fluticasone furoate (FF) and umeclidinium (UME) alone and in combination on these responses.

RESULTS

IL-5 and NF-κB levels were increased, and that of HDAC-2 reduced in sensitised HEBpCs. Pretreatment with FF reversed the effects of passive sensitisation by concentration-dependent reduction of IL-5, resulting in decreased NF-κB levels and restored HDAC-2 activity. Addition of UME enhanced these effects. Sensitized HEBpCs also exhibited higher ACh and ChAT levels. Pretreatment with UME significantly reduced ACh levels, and addition of FF caused a further small reduction.

CONCLUSION

This study confirmed that passive sensitisation of AECs results in an inflammatory response with increased levels of IL-5 and NF-κB, reduced levels of HDAC-2, and higher levels of ACh and ChAT compared to normal cells. Combining FF and UME was found to be more effective in reducing IL-5, NF-κB, and ACh and restoring HDAC-2 compared to the individual components. This finding supports adding a LAMA to established ICS/LABA treatment in asthma and suggests the possibility of using an ICS/LAMA combination when needed.

Is it preferable to administer a bronchodilator once- or twice-daily when treating COPD?

Nocturnal and early morning symptoms are common and uncomfortable in many patients with COPD, and are likely to affect their long-term outcomes. However, it is still debated whether it is better to give long-acting bronchodilators once- or twice-daily to symptomatic COPD patients. The functional link between circadian rhythms of autonomic tone and airway calibre explains why the timing of administration of bronchodilators in chronic airway diseases can induce different effects when taken at different biological (circadian) times. However, the timing also depends on the pharmacological characteristics of the bronchodilator to be used. Because the profile of bronchodilation produced by once-daily vs. twice-daily long-acting bronchodilators differs throughout 24 h, selecting long-acting bronchodilators may be customized to specific patient preferences based on the need for further bronchodilation in the evening. This is especially helpful for people who experience respiratory symptoms at night or early morning. Compared to placebo, evening bronchodilator administration is consistently linked with persistent overnight improvements in dynamic respiratory mechanics and inspiratory neural drive. The current evidence indicates that nocturnal and early morning symptoms control is best handled by a LAMA taken in the evening. In contrast, it seems preferable to use a LABA for daytime symptoms. Therefore, it can be speculated that combining a LAMA with a LABA can improve bronchodilation and control symptoms better. Both LAMA and LABA must be rapid in their onset of action. Aclidinium/formoterol, a twice-daily combination, is the most studies of the available LAMA/LABA combinations in terms of impact on daytime and nocturnal symptoms.

The long-term exercise after traumatic brain injury: Reharmonizing brain by sound body

Traumatic brain injuries (TBI) refer to multiple acquired dysfunctions arising from damage to the brain caused by an external force, including rapid acceleration/deceleration and concussion. Among them, mild TBI (mTBI) accounts for most cases (up to 90%) of injuries. It is responsible for a variety of symptoms, including anxiety, depression, and cognitive impairments that remain difficult to be treated. It has been reported that regular physical activity, as well as, improving life quality, display a neuroprotective function, suggesting a possible role in post-traumatic rehabilitation. In this study, we investigated the effects of treadmill exercise in a mice mTBI model by behavioural, electrophysiological and neurochemical analysis. Daily exercise decreased anxiety, aggressive behavior, and depression in mTBI mice. Accordingly, electrophysiological and neurochemical maladaptive rearrangement occurring in the hippocampus of mTBI mice were prevented by the exercise.

Advances in adrenergic receptors for the treatment of chronic obstructive pulmonary disease: 2023 update

INTRODUCTION

Strong scientific evidence and large experience support the use of β2-agonists for the symptomatic alleviation of COPD. Therefore, there is considerable effort in discovering highly potent and selective β2-agonists.

AREAS COVERED

Recent research on novel β2-agonists for the treatment of COPD. A detailed literature search was performed in two major databases (PubMed/MEDLINE and Scopus) up to September 2023."

EXPERT OPINION

Compounds that preferentially activate a Gs- or β-arrestin-mediated signaling pathway via β- adrenoceptors (ARs) are more innovative. Pepducins, which target the intracellular region of β2-AR to modulate receptor signaling output, have the most interesting profile from a pharmacological point of view. They stabilize the conformation of the β2-AR and influence its signaling by interacting with the intracellular receptor-G protein interface. New bifunctional drugs called muscarinic antagonist-β2 agonist (MABA), which have both muscarinic receptor (mAChR) antagonism and β2-agonist activity in the same molecule, are a new opportunity. However, all tested compounds have been shown to act predominantly as mAChR antagonists or β2-agonists. An intriguing idea is to utilize allosteric modulators that bind to β2-ARs at sites different than those bound by orthosteric ligands to augment or reduce the signaling transduced by the orthosteric ligand.

Strategies for overcoming the biological barriers associated with the administration of inhaled monoclonal antibodies for lung diseases

INTRODUCTION

Monoclonal antibodies (mAbs) should be administered by inhalation rather than parenterally to improve their efficiency in lung diseases. However, the pulmonary administration of mAbs in terms of aerosol technology and the formulation for inhalation is difficult.

AREAS COVERED

The feasible or suitable strategies for overcoming the barriers associated with administering mAbs are described.

EXPERT OPINION

Providing mAbs via inhalation to individuals with lung disorders is still difficult. However, inhalation is a desirable method for mAb delivery. Inhaled mAb production needs to be well thought out. The illness, the patient group(s), the therapeutic molecule selected, its interaction with the biological barriers in the lungs, the formulation, excipients, and administration systems must all be thoroughly investigated. Therefore, to create inhaled mAbs that are stable and efficacious, it will be essential to thoroughly examine the problems linked to instability and protein aggregation. More excipients will also need to be manufactured, expanding the range of formulation design choices. Another crucial requirement is for novel carriers for topical delivery to the lungs since carriers might significantly enhance proteins' stability and pharmacokinetic profile.

Early pathological changes of peri-coronal tissue in the distal area of erupted or partially impacted lower third molars

AIM

This study was performed to histologically evaluate peri-coronal tissues of partially impacted and erupted third molars that did not exhibit pathologic peri-coronal radiolucency.

MATERIALS AND METHODS

Healthy patients with erupted or partially erupted (with part or all of the dental crown present in the oral cavity) mandibular third molars (classified as IA and IIA according to the Pell and Gregory classification) and vertically positioned (according to the Winter classification or erupted third molars) associated with peri coronal radiolucency of equal to or less than 2.5 mm. Associated with third molar surgery, tissue sampling from the distal area was performed, which was subjected to an anatomopathological examination to determine the histological nature.

RESULTS

One hundred teeth (100 patients) were selected, and 100 specimens were analyzed. 53% of the sample were included in the non-pathological group and 47% showed pathological changes (fibrotic tissue (n 15), periodontal cyst-like (n 9), squamous epithelial metaplasia (4 cases), islands of odontogenic epithelial residues organized micro-cyst with keratocystic/ameloblastic appearance (4 cases), granulation tissue (n 8), giant cell tumour (n 4) and lobular capillary hemangioma (n 4)). Pathological changes did not have differences in incidence between the gender (p value = 0.85) and did not show any correlation with age, (p value = 0,96).

CONCLUSIONS

These findings suggest that radiographic appearance may not be a reliable indicator of the absence of disease within a dental follicle. Therefore, clinicians should pay attention to or follow up on even peri-coronal radiolucency of less than 2.5 mm.

Comparative study of the anaesthetic efficacy of 4% articaine versus 2% mepivacaine in mandibular third molar germectomy using different anaesthetic techniques: a split-mouth clinical trial

BACKGROUND

Currently, one of the most discouraging aspects for many patients undergoing dental procedures is the administration of local anaesthesia. Therefore, there is a constant search for new techniques to avoid the invasive and painful nature of the injection. This study aimed to compare the clinical efficacy of local anaesthetics with articaine 4% or mepivacaine 2% (both with epinephrine 1:100.000), using different anaesthetic techniques to perform germectomy of lower third molars and to assess patients' feelings and pain during surgery.

METHODS

Totally 50 patients (ranged 11-16 years) who required germectomy of mandibular third molars were recruited. Each patient received local anaesthesia on one side with articaine inoculated with plexus technique while on the other side with mepivacaine using inferior alveolar nerve block technique. The patients' evaluation was performed on pre and intraoperative tactile-pressure feelings and intraoperative pain with four levels on the Visual Analogue Scale (VAS).

RESULTS

Surgical operations lasted less with more efficient analgesia when articaine was used. The additional intraosseous injection was required mainly in the mepivacaine group intraoperatively. A few patients had tactile-pressure feelings while intraoperative pain sensation was absent in 90% of cases with articaine. Significant differences were found in the cases who reported "absent" and "moderate" VAS values, favoring the use of articaine.

CONCLUSIONS

Articaine injected with a plexus anaesthetic technique seems to be more clinically manageable than mepivacaine for the mandibular third molar germectomy. The discomfort of tactile-pressure feelings and pain experienced was lower using articaine anaesthetic technique used.

Pharmacokinetic considerations surrounding triple therapy for uncontrolled asthma

INTRODUCTION

Solid pharmacological rationale and clinical evidence support the use of a combination of an inhaled corticosteroid (ICS), a long-acting β2-agonist, and a long-acting muscarinic antagonist in severe asthma, which clinically results in increased lung function, improved symptoms, and decreased exacerbation rates.

AREAS COVERED

We examined the pharmacokinetic issues associated with triple therapy for uncontrolled asthma. We considered the pharmacokinetic characteristics of the three drug classes, the role of inhalers in influencing their pharmacokinetic behavior, and the impact of severe asthma on the pharmacokinetics of inhaled drugs.

EXPERT OPINION

The pharmacokinetics of ICSs and bronchodilators are not affected to a great extent by severe asthma, according to a detailed review of the currently accessible literature. Compared to healthy people, patients with severe asthma show only minor variations in a few pharmacokinetic characteristics, which are unlikely to have therapeutic significance and do not require particular attention. However, the difficulty of obtaining pharmacokinetic profiles of the three drugs included in a triple therapy suggests that the clinical response should be followed over time, which can be considered a good surrogate indicator of whether the drugs have reached sufficient concentrations in the lung to exert a valid pharmacological action.

Evaluation of unsulfated biotechnological chondroitin in a knee osteoarthritis mouse model as a potential novel functional ingredient in nutraceuticals and pharmaceuticals

Osteoarthritis is a very disabling disease that can be treated with both non-pharmacological and pharmacological approaches. In the last years, pharmaceutical-grade chondroitin sulfate (CS) and glucosamine emerged as symptomatic slow-acting molecules, effective in pain reduction and improved function in patients affected by osteoarthritis. CS is a sulfated glycosaminoglycan that is currently produced mainly by extraction from animal tissues, and it is commercialized as a pharmaceutical-grade ingredient and/or food supplement. However, public concern on animal product derivatives has prompted the search for alternative non-extractive production routes. Thus, different approaches were established to obtain animal-free natural identical CS. On the other hand, the unsulfated chondroitin, which can be obtained via biotechnological processes, demonstrated promising anti-inflammatory properties in vitro, in chondrocytes isolated from osteoarthritic patients. Therefore, the aim of this study was to explore the potential of chondroitin, with respect to the better-known CS, in an in vivo mouse model of knee osteoarthritis. Results indicate that the treatment with biotechnological chondroitin (BC), similarly to CS, significantly reduced the severity of mechanical allodynia in an MIA-induced osteoarthritic mouse model. Decreased cartilage damage and a reduction of inflammation- and pain-related biochemical markers were also observed. Overall, our data support a beneficial activity of biotechnological unsulfated chondroitin in the osteoarthritis model tested, thus suggesting BC as a potential functional ingredient in pharmaceuticals and nutraceuticals with the advantage of avoiding animal tissue extraction.

Clinical characteristics, treatment patterns and adherence in patients with asthma on multiple inhaler triple therapy: a review of findings

INTRODUCTION

The value of treating asthma with the triple regimen of inhaled corticosteroid (ICS), long-acting β2-agonist (LABA), and long-acting muscarinic antagonist (LAMA) delivered using multiple inhalers (MITT), or a single inhaler (SITT) is supported by a growing body of evidence, although research is still limited regarding the use of MITT.

AREAS COVERED

Clinical characteristics, treatment patterns, disease burden, and persistence/adherence associated with MITT use in asthma. The MEDLINE database was searched to identify references from inception until October 2022.

EXPERT OPINION

The use of MITT is not very frequent in asthma patients, although it improves lung function and reduces the incidence of severe exacerbations. This may be due to existing concerns about using different devices on adherence and persistence to treatment, with a negative influence on outcomes, and to the fear that the patient will discontinue ICS/LABA but not LAMA. Nevertheless, although the current trend favors the SITT approach, some physicians may be induced to prescribe MITT over SITT because it allows the titration of individual components of triple therapy to be increased or decreased. Therefore, there is an evident need for pragmatic real-life studies to document when to prefer SITT and when MITT should be used.

P06.07 Germline mutation of SMARCE1 gene in a family with spinal meningiomas

BACKGROUND

Meningioma is the most common benign primary intracranial tumor, arising from arachnoid cells of the meninges, but in 20% of cases displays aggressive behavior. Meningiomas are mainly sporadic and the familial forms are very rare. Meningioma account for a small subset (1–4%) of all pediatric brain tumors and may be associated with hereditary tumor predisposition syndrome caused by germline mutations of NF2, SMARCB1, SUFU, and SMARCE1 genes.

MATERIAL AND METHODS

We present a case of a 16-year-old girl with spinal clear cell meningiomas (CCMs) WHO II with a second spinal lesion identified during the follow-up. Considering the multiple lesions, we performed Whole Exome Sequencing (WES) on DNA from peripheral blood to search for an underlying CCMs tumor predisposition syndrome (#607174).

RESULTS

We identified a heterozygous frameshift variant c.439delA (p.Ser147fs) in SMARCE1, chromatin remodelling factor that acts as a tumor suppressor gene. Meningioma analysis by Sanger sequencing showed a loss of heterozygosity (LOH) of the wild-type allele. We identified the c.439delA in the constitutional DNA of the father and the sister but not in the mother. At the moment, the father is asymptomatic and the 14 years old sister showed two spinal lesions (meningiomas likely) at the first MRI.

CONCLUSION

We report a family study of hereditary tumor predisposition syndrome to CCMs with SMARCE1 mutation in which are present two asymptomatic carriers with different ages and gender. The asymptomatic carriers will undergo neurological examination and MRI of the brain and spine, according to a screening protocol. The incomplete penetrance phenomenon is known in SMARCE1-related families with CCMs and it is probably due to the interaction of SMARCE1 with yet unidentified genes.

Features of microvessel density (MVD) and angiogenesis inhibitors in therapeutic approach of hepatocellular carcinoma (HCC)

OBJECTIVE

The curative hepatocellular carcinoma (HCC) therapy was traditionally based on surgical or loco-regional ablation approach. However, HCC is a solid tumor characterized by a highest level of vascularization; therefore, angiogenesis inhibitor could play a pivotal role in the pharmacological therapeutic approach. Despite the low number of approved drugs, a wide range of multi-kinase and MET inhibitor is currently being evaluated in phase II and III study. In this review, we described all the drugs that have shown efficacy in recently and ongoing trials. Moreover, the immunotherapy represents a recent challenge in the HCC treatment. The strategy based on the production of multi-epitope, multi-HLA peptide vaccine naturally processed and presented on primary tumor tissues of HCC patients. A further upgrade of cancer vaccine could be represented by the combination of metronomic chemotherapy and checkpoint inhibitors.

Steroids and growth factors in oral squamous cell carcinoma: useful source of dental-derived stem cells to develop a steroidogenic model in new clinical strategies

OBJECTIVE

Head and neck region is involved in a high percentage of malignant lesions, and oral squamous cell carcinoma (OSCC) is undoubtedly the most frequently found, accounting for over 90% of malignant tumors. Hormone receptor overexpression, like Estrogen Receptor (ER), Progesterone Receptor (PR) and Endothelial Growth Factor Receptor (EGFR), and signaling have been related to the pathogenesis of OSCC. For metastasis of OSCC, Cancer Stem Cells (CSCs) undergo epithelial to mesenchymal transition (EMT) under the influence of growth factors, cytokines, and regulation of cadherins from the tumor's microenvironment. In this context, the stem cells may become a potential therapeutic target for OSCC through modulation of cytokines and RAS pathway, which is involved in intracell signal transduction. The objective of this study was to suggest an experimental steroidogenic model for OSCC in translational research.

PATIENTS AND METHODS

Dental-derived Stem Cells (D-dSCs) have been obtained from apical papilla tissue that surrounds the developing tooth of healthy donors and cultured in vitro. The cells have been exposed to different concentrations of Estradiol (E2 - 10 nM and 40 nM) in order to verify their response. The number of cells and cell viability has been evaluated up to 96 hours of treatment.

RESULTS

The results showed that cell growth was increased under estradiol treatments compared with cells maintained without estradiol. Moreover, no significant difference in cell death levels was detected among treatments.

CONCLUSIONS

This work underlines as D-dSCs could represent a useful steroidogenic model for the development of the target and gene therapies in OSCC.

An in vitro study to assess the effect of hyaluronan-based gels on muscle-derived cells: Highlighting a new perspective in regenerative medicine

Hyaluronan (HA) is a nonsulfated glycosaminoglycan that has been widely used for biomedical applications. Here, we have analyzed the effect of HA on the rescue of primary cells under stress as well as its potential to recover muscle atrophy and validated the developed model in vitro using primary muscle cells derived from rats. The potentials of different HAs were elucidated through comparative analyses using pharmaceutical grade a) high (HHA) and b) low molecular weight (LHA) hyaluronans, c) hybrid cooperative complexes (HCC) of HA in three experimental set-ups. The cells were characterized based on the expression of myogenin, a muscle-specific biomarker, and the proliferation was analyzed using Time-Lapse Video Microscopy (TLVM). Cell viability in response to H₂O₂ challenge was evaluated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression of the superoxide dismutase enzyme (SOD-2) was assessed by western blotting. Additionally, in order to establish an in vitro model of atrophy, muscle cells were treated with tumor necrosis factor-alpha (TNF-α), along with hyaluronans. The expression of Atrogin, MuRF-1, nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-kB), and Forkhead-box-(Fox)-O-3 (FoxO3a) was evaluated by western blotting to elucidate the molecular mechanism of atrophy. The results showed that HCC and HHA increased cell proliferation by 1.15 and 2.3 folds in comparison to un-treated cells (control), respectively. Moreover, both pre- and post-treatments of HAs restored the cell viability, and the SOD-2 expression was found to be reduced by 1.5 fold in HA-treated cells as compared to the stressed condition. Specifically in atrophic stressed cells, HCC revealed a noteworthy beneficial effect on the myogenic biomarkers indicating that it could be used as a promising platform for tissue regeneration with specific attention to muscle cell protection against stressful agents.

Emerging muscarinic receptor antagonists for the treatment of asthma

INTRODUCTION

The increased acetylcholine signaling in asthma pathophysiology offers the rationale for the use of LAMAs in the treatment of asthmatic patients. Tiotropium is still the only LAMA approved for use in asthma but there is a real interest in developing novel LAMAs for the treatment of asthma, or at least to extend this indication to other LAMAs already on the market.

AREAS COVERED

We examined and discussed trials and research that have studied or are evaluating the role of LAMAs already on the market in asthma and possible novel muscarinic acetylcholine receptor antagonists.

EXPERT OPINION

Glycopyrronium and umeclidinium will soon be included in the GINA strategy with the same current indications of tiotropium. It is likely that the choice of the LAMA will be influenced not so much by its pharmacological profile as by the type of triple therapy chosen. It is extremely difficult to identify a new LAMA that is more effective than tiotropium, but is it plausible that new technologies that will allow delivering the drug in a more targeted way and with a lower risk of adverse effects may represent the real progress in the use of LAMAs in asthma in the coming years.

New perspectives on the role of muscarinic antagonists in asthma therapy

INTRODUCTION

There is increasing evidence that tiotropium, a long-acting muscarinic agent (LAMA), is useful in the presence of severe-uncontrolled asthma despite the optimization of therapy with inhaled corticosteroids (ICSs) and long-acting β₂ agonists (LABAs) as recommended by the current guidelines. Furthermore, in recent years there have been several  preclinical and clinical studies on the pharmacological and therapeutic impact of other LAMAs in asthma.

AREAS COVERED

We have conducted an extensive search on muscarinic antagonists in asthma therapy throughout several sources and discuss what has emerged in the last 3 years (January 2017-March 2020).

EXPERT OPINION

New evidence indicates that the effectiveness of adding a LAMA, at least tiotropium, is independent of the degree of the type 2 inflammation and age of patient. Therefore, tiotropium can be administered without the need for patient phenotyping. Umeclidinium and glycopyrronium also appear effective in asthma. Initial treatment with LAMA+ICS for those with mild asthma may be an equally effective therapeutic option as LABA+ICS but this hypothesis should be confirmed by statistically powered trials.

A review of the pharmacokinetics of M3 muscarinic receptor antagonists used for the treatment of asthma

Introduction: There is solid evidence that in patients with poorly controlled severe asthma despite the use of ICS and LABA, the addition of LAMAs, such as tiotropium, significantly increases the time to the first severe exacerbation and provides a modest but sustained bronchodilation. However, only a very limited number of pharmacokinetic studies with these agents have been performed in asthmatic patients.Areas covered: The pharmacokinetic profile of inhaled tiotropium, umeclidinium and glycopyrronium in healthy volunteers and that of inhaled tiotropium and umeclidinium in asthmatic patients have been reviewed.Expert opinion: In asthmatic patients, LAMAs are rapidly absorbed into the systemic compartment and demonstrate bi-exponential elimination (rapidly declining plasma concentrations followed by slow apparent terminal elimination). Apparently, the severity of asthma does not change the pharmacokinetics of LAMAs. The limited information available is focused on the plasma pharmacokinetic profile of these drugs and, consequently, although suitable for establishing a systemic safety profile, it does not tell us much about possible therapeutic efficacy of LAMAs in asthmatics because quantification of systemic plasma values is neither at the airways, which are their site of action nor representative of their transport to this site.

Pharmacokinetics and pharmacodynamics of inhaled corticosteroids for asthma treatment

The differences in the pharmacokinetic (PK) characteristics of inhaled corticosteroids (ICSs) critically influence the profile of each of them, but also the significant differences in glucocorticoid receptor selectivity, potency, and physicochemical properties are critical in defining the pharmacodynamic (PD) profile of an ICS. The PK and PD properties of ICSs used in asthma and the importance of their interrelationship have been reviewed. The differences among the ICSs in PK and PD must be considered when an ICS should be prescribed to an asthmatic patient because a better understanding of the PK/PD interrelationship of ICSs could be important to better fit with the between-patient variability and within-patient repeatability in the response to ICSs that often complicate the therapeutic approach to the asthmatic patient. The role of the device in influencing the PK profile of an ICS must be always considered because it is crucial. Also patient-related factors and disease severity affect pulmonary deposition of ICS.

Addition of the Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m to Prolonged and Moderate Exercise Training Enhanced Protection of the Rat Heart From Type-1 Diabetes

Moderate exercise training may not be sufficient to exert beneficial effects on the cardiovascular system because of the long-term multifactorial etiology of diabetic complications. The addition of a proper pharmacological tool to the physical exercise should improve the outcomes of the diabetic damage. Here it is shown that 8 weeks exercise training of type 1 diabetic Sprague-Dawley (SD) rats resulted in a significantly increased heart rate, a 14% increase in the left ventricular ejection fraction (LVEF) increased plasma insulin levels and a 13% decrease in plasma glucose with respect to sedentary animals. The training also resulted in a 22% reduction in cardiac QT interval from a diabetic sedentary value of 185 ± 19 ms. Treatment of trained rats with the new antioxidant and NO-releasing aldose reductase 2 inhibitor 5(6)-(benzo[d]thiazol-2-ylmethoxy) benzofuroxane BF-5m, 20 mg/kg/day, added a further and significant (P < 0.01 vs. sedentary) increase of the LVEF up to 38% at 8 week time point. The long QT interval recorded in trained rats was reduced to further 12% by addition to the training of pharmacological treatment with 20 mg/kg/day BF-5m. At this time, the association of the two treatments improved the expression into the cardiac tissue of sarcoplasmic reticulum Ca²⁺ ATPase 2 (SERCA2) and manganese superoxide dismutase (MnSOD), and reduced the fibrosis.

AT1-receptor blockade: Protective effects of irbesartan in cardiomyocytes under hypoxic stress

Hypoxia induces myocardial injury through the activation of inflammatory and oxidative processes. The pivotal role of the renin angiotensin system (RAS) in the pathogenesis of cardiovascular diseases has been firmly established in clinical trials and practice; in fact many experimental and clinical data have highlighted that its inhibition has a cardioprotective role. Activated RAS also stimulates inflammation directly inducing proinflammatory and oxidative gene expression. This study aimed to investigate the protective role of a pre-treatment (10 and 100 μM) with irbesartan on injury induced by 24 h of hypoxia in HL-1 cardiomyocytes; in particular, we have analyzed the natriuretic peptide (BNP) expression, a biomarker able to modulate inflammatory reaction to cardiac injury and some markers involved in oxidative stress and inflammation. Our results demonstrated that a pre-treatment with 100 μM irbesartan significantly increased SOD activity and catalase expression of 15 and 25%, respectively, compared to hypoxic cells (P<0.05). On the other hand, it was able to reduce the release of peroxynitrite and iNOS protein expression of 20 and 50% respectively (P<0.05). In addition irbesartan exerts an anti-inflammatory activity reducing Toll-like receptors (TLRs)-2 and -4 mRNA expression, TNF-alpha expression and activity (20%) and increasing the expression of the cytokine IL-17 (40%) (P<0.05 vs hypoxia). Our findings also showed that BNP induced by ischemia was significantly and in a concentration-dependent manner reduced by irbesartan. The findings of our study demonstrated that the AT1 receptor antagonist irbesartan exerts a protective role in an in vitro hypoxic condition reducing oxidative stress and inflammation.

Role of statins and mevalonate pathway on impaired HDAC2 activity induced by oxidative stress in human airway epithelial cells

In patients with chronic obstructive pulmonary disease (COPD) the inflammatory response is often steroid-resistant, likely since oxidative stress and cigarette smoking impair histone deacetylase 2 (HDAC2) activity. Since it has been demonstrated that statins may restore the HDAC2 activity in cultured human endothelial cells, the aim of this study was to investigate the effects of statins in reversing the steroid-resistance induced by oxidative stress. We evaluated the effects of simvastatin and dexamethasone on HDAC2 expression and activity, and the role of mevalonate and Rho/ROCK pathways in A549 cells, a human lung type II epithelial cell line stressed with H₂O₂. Our results documented that H₂O₂ significantly reduced the HDAC2 expression and activity. In H₂O₂ treated cells dexamethasone was unable to restore the activity of HDAC2, whereas simvastatin restored both the expression and the activity of this enzyme. Our data also showed that mevalonate reduced the activity of HDAC2 whereas Y27632, a Rho/ROCK inhibitor, had no effect on HDAC2 activity when co-administered with simvastatin. Our data suggest that statins could have the potential to restore corticosteroid sensitivity in A549 cells. The evidences of this study suggest that, although both mevalonate and Rho/ROCK pathways are involved in the detrimental effect elicited by oxidative stress, statins may restore the function and expression of depleted HDAC2 via modulating the mevalonate cascade, at least in A549 cells. In conclusion, the modulation of histone acetyltransferase/deacetylase activity may lead to the development of novel anti-inflammatory approaches to inflammatory lung diseases that are currently difficult to treat.

β2-Adrenoceptor signalling bias in asthma and COPD and the potential impact on the comorbidities associated with these diseases

Inhaled selective β2-agonists are the most widely used treatment for obstructive airway diseases. The classical mechanism of action of these drugs is considered as their ability to activate β2-adrenergic receptors (β2-AR) on airway smooth muscle leading to G-protein activation and subsequent generation of c-AMP causing bronchodilation. However, there is now growing evidence to suggest that binding of β2-agonists to β2-AR is pleotropically coupled to many intracellular pathways whereby depending on the state of the β2-AR when activated, a subset of different intracellular responses can be triggered. This is called biased agonism (or functional selectivity) and this type of activity has now been observed with different types of G protein-coupled receptor (GPCR), not just β2-AR. Accordingly, drug efficacy for many agonists binding to GPCRs can no longer be solely described in terms of a single relationship between binding of a ligand to a receptor and the subsequent magnitude of the cellular response, but is often far more complex reflecting a specific complement of signals following binding of a ligand to its receptor. These differences in responses depending on what state the receptor is in when the ligand binds to it can subsequently influence the intracellular signalling that in turn can influence the efficacy of β2-AR ligands. Such findings suggest that in the future it may be possible to develop new synthetic β2-agonists that could preferentially confine their activity in stabilizing/activating the receptor to a certain conformation which could lead to improved drugs either to reduce adverse responses or to avoid drugs that activate certain conformations of the receptors that may lead to tolerance or desensitization following repeated activation.

Inhibition of p110δ PI3K prevents inflammatory response and restenosis after artery injury

Inflammatory cells play key roles in restenosis upon vascular surgical procedures such as bypass grafts, angioplasty and stent deployment but the molecular mechanisms by which these cells affect restenosis remain unclear. The p110δ isoform of phosphoinositide 3-kinase (PI3K) is mainly expressed in white blood cells. Here, we have investigated whether p110δ PI3K is involved in the pathogenesis of restenosis in a mouse model of carotid injury, which mimics the damage following arterial grafts. We used mice in which p110δ kinase activity has been disabled by a knockin (KI) point mutation in its ATP-binding site (p110δD910A/D910A PI3K mice). Wild-type (WT) and p110δD910A/D910A mice were subjected to longitudinal carotid injury. At 14 and 30 days after carotid injury, mice with inactive p110δ showed strongly decreased infiltration of inflammatory cells (including T lymphocytes and macrophages) and vascular smooth muscle cells (VSMCs), compared with WT mice. Likewise, PI-3065, a p110δ-selective PI3K inhibitor, almost completely prevented restenosis after artery injury. Our data showed that p110δ PI3K plays a main role in promoting neointimal thickening and inflammatory processes during vascular stenosis, with its inhibition providing significant reduction in restenosis following carotid injury. p110δ-selective inhibitors, recently approved for the treatment of human B-cell malignancies, therefore, present a new therapeutic opportunity to prevent the restenosis upon artery injury.

Pharmacogenetic and pharmacogenomic considerations of asthma treatment

INTRODUCTION

Pharmacogenetic and pharmacogenomic approaches are already utilized in some areas, such as oncology and cardiovascular disease, for selecting appropriate patients and/or establishing treatment and dosing guidelines. This is not true in asthma although many patients have different responses to drug treatment due to genetic factors. Areas covered: Several genetic factors that affect the pharmacotherapeutic responses to asthma medications, such as β₂-AR agonists, corticosteroids, and leukotriene modifiers and could contribute to significant between-person variability in response are described. Expert opinion: An expanding number of genetic loci have been associated with therapeutic responses to asthma drugs but the individual effect of one single-nucleotide polymorphism is partial. In fact, epigenetic changes can modify genetic effects in time-, environment-, and tissue-specific manners, genes interact together in networks, and nongenetic components such as environmental exposures, gender, nutrients, and lifestyle can significantly interact with genetics to determine the response to therapy. Therefore, well-designed randomized controlled trials or observational studies are now mandatory to define if response to asthma medications in individual patients can be improved by using pharmacogenetic predictors of treatment response. Meanwhile, routine implementation of pharmacogenetics and pharmacogenomics into clinical practice remains a futuristic, far-off challenge for many clinical practices.

Diagnostic application of a capture based NGS test for the concurrent detection of variants in sequence and copy number as well as LOH

Whole exome sequencing (WES) has made the identification of causative SNVs/InDels associated with rare Mendelian conditions increasingly accessible. Incorporation of softwares allowing CNVs detection into the WES bioinformatics pipelines may increase the diagnostic yield. However, no standard protocols for this analysis are so far available and CNVs in non-coding regions are totally missed by WES, in spite of their possible role in the regulation of the flanking genes expression. So, in a number of cases the diagnostic workflow contemplates an initial investigation by genomic arrays followed, in the negative cases, by WES. The opposite workflow may also be applied, according to the familial segregation of the disease. We show preliminary results for a diagnostic application of a single next generation sequencing panel permitting the concurrent detection of LOH and variations in sequences and copy number. This approach allowed us to highlight compound heterozygosity for a CNV and a sequence variant in a number of cases, the duplication of a non-coding region responsible for sex reversal, and a whole-chromosome isodisomy causing reduction to homozygosity for a WFS1 variant. Moreover, the panel enabled us to detect deletions, duplications, and amplifications with sensitivity comparable to that of the most widely used array-CGH platforms.

Pharmacokinetic/pharmacodynamic drug evaluation of benralizumab for the treatment of asthma

INTRODUCTION

In many severe asthmatics, eosinophils cause inflammation and airways hyperresponsiveness, resulting in frequent exacerbations, impaired lung function, and reduced quality of life. Interleukin-5 (IL-5) is a key cytokine for eosinophil growth, differentiation, recruitment, activation, and survival. Anti-IL-5-based therapies (mepolizumab and reslizumab are humanized monoclonal antibodies (hmAbs) that recognize free IL-5, benralizumab is a hmAb directed at the α subunit of the IL-5R) target the IL-5-signaling in eosinophilic asthma. Areas covered: The pharmacodynamic/pharmacokinetic profile of benralizumab and how it provided indications that permitted optimization of the design and timelines of the pivotal trials are described. Expert opinion: Benralizumab has the advantage over other anti-IL-5 therapies to target the IL-5Rα itself. Afucosylation enhances its interaction with its binding site and facilitates its pharmacological activity. Other benefits of benralizumab are fast (within 24 h) depletion of peripheral blood eosinophils, potent suppressive activity of bone marrow eosinophils and eosinophil precursors, tissue eosinophil apoptosis regardless of the presence of eosinophil survival factors and even at low IL-5R densities. The fact that benralizumab is dosed subcutaneously and is equally effective when given every eight weeks instead than every four weeks provides patients with convenience of self-administration and make it appealing for patients who dislike injections.

Assessing the viability of long-acting β2-agonists in paediatric asthma patients: a pharmacokinetic/pharmacodynamic perspective

INTRODUCTION

Long-acting β₂-agonists (LABAs) combined with inhaled corticosteroids (ICSs) are still commonly prescribed to asthmatic children. Unfortunately, pediatric LABA use is based primarily on data from adults, despite the fact that children are not simply small adults and the magnitude of changes in dose exposure and/or exposure response may not be solely reflected by differences in body weight. Areas covered: The differences in pharmacokinetics (PK) and pharmacodynamics (PD) of LABAs are described and discussed with reference children and adults. Expert opinion: Data on the PK behavior of LABAs is very limited and there is almost no data on once-daily LABAs available in the pediatric population. We do not believe that this is due to a fundamental lack of information because therapeutic response and adverse effects are more useful for the optimization of β₂-agonist treatment than measurement of plasma drug concentrations per se. Nevertheless, population PK-PD studies in children are needed according to the European rules in order to define rational, patient-tailored dosing schemes. Population PK-PD modeling and simulation using non-linear mixed effect modeling should be considered as the preferred tool to develop effective and safe dosing regimens for children because they present an opportunity to analyze sparse and unbalanced datasets, thereby minimizing the burden for each child.

Brain natriuretic peptide: Much more than a biomarker

Brain natriuretic peptide (BNP) modulates several biological processes by activating the natriuretic peptide receptor A (NPR-A). Atria and ventricles secrete BNP. BNP increases natriuresis, diuresis and vasodilatation, thus resulting in a decreased cardiac workload. BNP and NT-proBNP, which is the biologically inactive N-terminal portion of its pro-hormone, are fast and sensitive biomarkers for diagnosing heart failure. The plasma concentrations of both BNP and NT-proBNP also correlate with left ventricular function in patients with acute exacerbation of COPD, even without history of heart failure. Several studies have been conducted in vitro and in vivo, both in animals and in humans, in order to assess the potential role of the NPR-A activation as a novel therapeutic approach for treating obstructive pulmonary disorders. Unfortunately, these studies have yielded conflicting results. Nevertheless, further recent specific studies, performed in ex vivo models of asthma and COPD, have confirmed the bronchorelaxant effect of BNP and its protective role against bronchial hyperresponsiveness in human airways. These studies have also clarified the intimate mechanism of action of BNP, represented by an autocrine loop elicited by the activation of NPR-A, localized on bronchial epithelium, and the relaxant response of the surrounding ASM, which does not expresses NPR-A. This review explores the teleological activities and paradoxical effects of BNP with regard to chronic obstructive respiratory disorders, and provides an excursus on the main scientific findings that explain why BNP should be considered much more than a biomarker.

Pharmacodynamic and pharmacokinetic assessment of fluticasone furoate + vilanterol for the treatment of asthma

INTRODUCTION

The pharmacokinetic (PK) and pharmacodynamic (PD) effects of long-acting β2-agonists and mostly inhaled corticosteroids (ICSs) shape the efficacy and safety of these agents in the treatment of asthma. In fact, the PK and PD characteristics of the drug largely determine the degree of pulmonary targeting Areas covered. In this review, we summarize the PK and PD properties of inhaled fluticasone furoate (FF) and vilanterol trifenatate (VI) and their fixed-dose combination (FDC) for the treatment of asthma Expert opinion. It is difficult to interpret the data that we have described because the preclinical and clinical development of FF/VI FDC was not really based on solid information on quantitative PK/PD approach. Unfortunately, for both FF and VI we only know concentrations in systemic blood, a compartment that is downstream of both target and non-target respiratory tissue. This lack of information does not allow us to understand the temporal relationship between the delivered dose and the drug concentration at the sites of action within the lungs. In addition, all studies performed with FF and VI did not address the fundamental issue that asthma can significantly alter lung deposition, absorption and also clearance of inhaled medicines.

Olodaterol for the treatment of asthma

INTRODUCTION

Long-acting β-agonist (LABA)/inhaled corticosteroid (ICS) combinations are still the mainstay of asthma therapy but there is a pressing need to increase adherence to the prescribed treatment achievable in general by reducing the dose frequency. Consequently, there is considerable interest within the pharmaceutical industry in the discovery of once-daily β2-agonists (ultra-LABAs) to be used as a part of a combination therapy for treating asthma.

AREAS COVERED

The authors review the preclinical and clinical development of olodaterol, a new ultra-LABA characterized by an improved selectivity for β2-adrenoceptors and a rather high intrinsic efficacy profile, in asthma. The clinical results were generated by 4 Phase 2 trials, which have enrolled 731 asthmatic patients.

EXPERT OPINION

The available results indicate that olodaterol is able to induce an effective 24-h bronchodilation and is safe. However, one cannot formulate a solid conclusion on the best dose and/or dose frequency to be used in asthma because trials were not powered to assess the differences between doses and dose frequencies. Apparently, there is no Phase 3 trial planned or ongoing for olodaterol monotherapy in patients with asthma and also no attempt to combine olodaterol with an ICS, which is surprising.

Primary and Acquired Resistance of Colorectal Cancer to Anti-EGFR Monoclonal Antibody Can Be Overcome by Combined Treatment of Regorafenib with Cetuximab

PURPOSE

In colorectal cancer, the activation of the intracellular RAS-RAF and PIK3CA-AKT pathways has been implicated in the resistance to anti-EGFR mAbs. We have investigated the role of regorafenib, an oral multikinase inhibitor, in combination with cetuximab, an anti-EGFR mAb, to overcome anti-EGFR resistance.

EXPERIMENTAL DESIGN

We have tested, in vitro and in vivo, the effects of regorafenib in a panel of human colorectal cancer cell lines with a KRAS mutation (SW480, SW620, HCT116, LOVO, and HCT15) or with a BRAF mutation (HT29), as models of intrinsic resistance to cetuximab treatment, and in two human colorectal cancer cell lines (GEO and SW48) that are cetuximab-sensitive, as well as in their derived cells with acquired resistance to cetuximab (GEO-CR and SW48-CR).

RESULTS

Treatment with regorafenib determined a dose-dependent growth inhibition in all colorectal cancer cell lines. The combined treatment with cetuximab and regorafenib induced synergistic antiproliferative and apoptotic effects in cetuximab-resistant cell lines by blocking MAPK and AKT pathways. Nude mice were injected s.c. with HCT116, HCT15, GEO-CR, and SW48-CR cells. The combined treatment caused significant tumor growth inhibition. Synergistic antitumor activity of regorafenib plus cetuximab was also observed in an orthotopic colorectal cancer model of HCT116 cells. In particular, the combined treatment induced a significant tumor growth inhibition in the primary tumor site (cecum) and completely prevented metastasis formation.

CONCLUSIONS

The combined treatment with cetuximab and regorafenib could be a strategy to overcome resistance to anti-EGFR therapies in metastatic colorectal cancer patients.

Effects of chronic treatment with the new ultra-long-acting β2 -adrenoceptor agonist indacaterol alone or in combination with the β1 -adrenoceptor blocker metoprolol on cardiac remodelling

BACKGROUND AND PURPOSE

The ability of a chronic treatment with indacaterol, a new ultra-long-acting β2 -adrenoceptor agonist, to reverse cardiac remodelling and its effects in combination with metoprolol, a selective β1 -adrenoceptor antagonist, were investigated on myocardial infarction in a rat model of heart failure (HF).

EXPERIMENTAL APPROACH

We investigated the effects of indacaterol and metoprolol, administered alone or in combination, on myocardial histology, β-adrenoceptor-mediated pathways, markers of remodelling and haemodynamic parameters in a rat model of HF. Five groups of rats were assessed: sham-operated rats; HF rats; HF + indacaterol 0.3 mg·kg(-1) ·day(-1) ; HF + metoprolol 100 mg·kg(-1) ·day(-1) ; HF + metoprolol + indacaterol. All pharmacological treatments continued for 15 weeks.

KEY RESULTS

Treatment with either indacaterol or metoprolol significantly reduced the infarct size in HF rats. However, the combination of indacaterol and metoprolol reduced the infarct size even further, reduced both BP and heart rate, reversed the decrease in ejection fraction, normalized left ventricular systolic and diastolic internal diameters, normalized the decreased β1 adrenoceptor mRNA expression as well as cardiac cAMP levels and reduced cardiac GPCR kinase 2 expression, compared with the untreated HF group.

CONCLUSION AND IMPLICATIONS

The results of our study demonstrated an additive interaction between indacaterol and metoprolol in normalizing and reversing cardiac remodelling in our experimental model of HF. The translation of these findings to clinical practice might be of interest, as this combination of drugs could be safer and more effective in patients suffering from HF and COPD.

Contribution of sensory nerves to LPS-induced hyperresponsiveness of human isolated bronchi

AIMS

Bacterial lipopolysaccharide (LPS) can induce bronchial hyperresponsiveness (BHR), but the underlying mechanisms remain to be determined. Here, the possible contribution of sensory nerves to LPS-induced BHR was examined in human isolated bronchi to pharmacologically identify the mechanisms underlying this phenomenon.

MAIN METHODS

Human isolated bronchial tone was induced by electrical field stimulation (EFS). The responses of airways to LPS, with or without capsaicin desensitization or thiorphan treatment were studied and the transient receptor potential vanilloid type 1 (TRPV1) expression was assessed. We performed similar experiments in the presence of a TRPV1 or a neurokinin (NK) 2 receptor antagonist using SB366791 and GR159897, respectively.

KEY FINDINGS

LPS increased (≃2.3-fold, P<0.001) the contraction induced by EFS, compared to control tissues. Acute administration of capsaicin enhanced (≃2.3-fold, P<0.001) the EFS-mediated contraction, but did not potentiate the effect of LPS. Thiorphan increased (≃1.3-fold, P<0.05) the contractile response of LPS treated tissues and, at lower frequencies, it enhanced (≃1.7-fold, P<0.001) the capsaicin-induced contraction. In capsaicin-desensitized bronchi, LPS did not modify (P>0.05) the EFS contractile response, nor after treatment with thiorphan. Capsaicin desensitization reduced (≃0.4-fold, P<0.001) the LPS-induced BHR. SB366791 and GR159897 prevented the LPS-induced BHR and the release of NKA. LPS increased (+85.3±9.5%, P<0.01) the surface membrane expression of TRPV1 in parasympathetic ganglia.

SIGNIFICANCE

Our results demonstrate the involvement of capsaicin-sensitive sensory nerves and neutral endopeptidases in LPS-induced BHR of the human bronchi, associated with an upregulation of TRPV1 and release of NKA.

Effects of chronic administration of β-blockers on airway responsiveness in a murine model of heart failure

Lung function abnormalities, both at rest and during exercise, are frequently observed in patients with chronic heart failure (HF), also in absence of respiratory disease. It has been documented that, in HF, chronic adrenergic stimulation down-regulates β-adrenoceptors (β-ARs) and modifies airway relaxant responses. This study was designed to investigate in an animal model of HF whether a treatment with a β-AR blocker, metoprolol, could modify the altered airway hyperresponsiveness. In rats, randomly assigned to 3 experimental groups sham-operated rats (SH), rats with HF induced by left anterior descending coronaric occlusion (HF n = 10), and rats treated with metoprolol 100 mg/kg/die (MET = 10), HF was evaluated after 10 weeks and resulted in increases in plasma norepinephrine and epinephrine and left ventricular end diastolic pressure. β2-ARs and G-protein-βAR2-kinase (GRK2) mRNA levels were determined by real time reverse transcriptase PCR. Carbachol-precontracted isolated tracheal rings were used to functionally assess airway smooth muscle relaxation. In pulmonary tissues, β2-AR mRNA level was significantly decreased in HF groups (-48.73 ± 5.18%, P < 0.01); in the same groups the GRK2 mRNA-levels were significantly enhanced (+222.50 ± 6.13%, P < 0.001); in lung deriving from MET groups the levels of mRNA were significantly increased (+339.86 ± 11.26%, P < 0.001), while the GRK2 mRNA-levels unchanged (-59.02 ± 3.97%, P < 0.001), when compared to SH groups. Relaxation of tracheal strips in response to salbutamol was significantly reduced in HF groups; in tracheal rings, deriving from MET groups, the relaxant effects of salbutamol were significantly enhanced (SH, Emax: 34.87 ± 2.98%, pD2: 7.45 ± 0.27; HF, Emax: 34.87 ± 2.98%, pD2: 7.45 ± 0.27; MET, Emax: 85.43 ± 6.80%, pD2: 6.95 ± 0.59, P < 0.001). In HF, the down-regulation of pulmonary β-ARs results in a significant attenuation of airway relaxation. These effects have been reversed by a treatment with metoprolol, suggesting a potential role of β-AR blockers in the treatment of patients suffering from HF and chronic obstructive airway diseases.