MUC1 intracellular bioactivation mediates lung fibrosis.

BACKGROUND: Serum KL6/mucin 1 (MUC1) has been identified as a potential biomarker in idiopathic pulmonary fibrosis (IPF), but the role of MUC1 intracellular bioactivation in IPF is unknown. OBJECTIVE: To characterise MUC1 intracellular bioactivation in IPF. METHODS AND RESULTS: The expression and phosphorylation of Thr41 and Tyr46 on the intracellular MUC1-cytoplasmic tail (CT) was increased in patients with IPF (n=22) compared with healthy subjects (n=21) and localised to fibroblasts and hyperplastic alveolar type II cells. Transforming growth factor (TGF)-ß1 phosphorylated SMAD3 and thereby increased the phosphorylation of MUC1-CT Thr41 and Tyr46 in lung fibroblasts and alveolar type II cells, activating ß-catenin to form a phospho-Smad3/MUC1-CT and MUC1-CT/ß-catenin nuclear complex. This nuclear complex promoted alveolar epithelial type II and fibroblast to myofibroblast transitions, as well as cell senescence and fibroblast proliferation. The inhibition of MUC1-CT nuclear translocation using the inhibitor, GO-201 or silencing MUC1 by siRNA, reduced myofibroblast transition, senescence and proliferation in vitro. Bleomycin-induced lung fibrosis was reduced in mice treated with GO-201 and in MUC1-knockout mice. The profibrotic lectin, galectin-3, directly activated MUC1-CT and served as a bridge between the TGF-ß receptor and the MUC1-C domain, indicating TGF-ß1-dependent and TGF-ß1-independent intracellular bioactivation of MUC1. CONCLUSIONS: MUC1 intracellular bioactivation is enhanced in IPF and promotes fibrotic processes that could represent potential druggable targets for IPF.

Mucin 1 deficiency mediates corticosteroid insensitivity in asthma.

BACKGROUND: The loss of corticosteroid efficacy is an important issue in severe asthma management and may lead to poor asthma control and deterioration of airflow. Recent data indicate that Mucin 1 (MUC1) membrane mucin can mediate corticosteroid efficacy in chronic rhinosinusitis, but the role of MUC1 in uncontrolled severe asthma is unknown. The objective was to analyze the previously unexplored role of MUC1 on corticosteroid efficacy in asthma. METHODS: Mucin 1 expression was evaluated by real-time PCR in human bronchial epithelial cells (HBEC) and blood neutrophils from uncontrolled severe asthma (n = 27), controlled mild asthma (n = 16), and healthy subjects (n = 13). IL-8, MMP9, and GM-CSF were measured by ELISA in HBEC and neutrophils. An asthma model of ovalbumin (OVA) was used in MUC1 KO and WT C57BL/6 mice according to ARRIVE guidelines. RESULTS: Mucin 1-CT expression was downregulated in bronchial epithelial cells and peripheral blood neutrophils from severe asthma patients compared with mild asthma and healthy subjects (P < 0.05). Daily dose of inhaled corticosteroids (ICS) inversely correlated with MUC1 expression in neutrophils from mild and severe asthma (ρ = -0.71; P < 0.0001). Dexamethasone showed lower anti-inflammatory effects in severe asthma peripheral blood neutrophils and HBECs stimulated with lipopolysaccharide (LPS) than in cells from mild asthma. Glucocorticoid receptor (GR)-α phosphorylated at serine 226 was increased in cells from severe asthma, and the MUC1-CT/GRα complex was downregulated in severe asthma cells. OVA asthma model in MUC1 KO mice was resistant to the anti-inflammatory effects of dexamethasone. CONCLUSION: Mucin 1-CT modulates corticosteroid efficacy in vitro and in vivo asthma models.

JAK2 mediates lung fibrosis, pulmonary vascular remodelling and hypertension in idiopathic pulmonary fibrosis: an experimental study.

BACKGROUND: Pulmonary hypertension (PH) is a common disorder in patients with idiopathic pulmonary fibrosis (IPF) and portends a poor prognosis. Recent studies using vasodilators approved for PH have failed in improving IPF mainly due to ventilation (V)/perfusion (Q) mismatching and oxygen desaturation. Janus kinase type 2 (JAK2) is a non-receptor tyrosine kinase activated by a broad spectrum of profibrotic and vasoactive mediators, but its role in PH associated to PH is unknown. OBJECTIVE: The study of JAK2 as potential target to treat PH in IPF. METHODS AND RESULTS: JAK2 expression was increased in pulmonary arteries (PAs) from IPF (n=10; 1.93-fold; P=0.0011) and IPF+PH (n=9; 2.65-fold; P<0.0001) compared with PA from control subjects (n=10). PA remodelling was evaluated in human pulmonary artery endothelial cells (HPAECs) and human pulmonary artery smooth muscle cells (HPASMCs) from patients with IPF in vitro treated with the JAK2 inhibitor JSI-124 or siRNA-JAK2 and stimulated with transforming growth factor beta. Both JSI-124 and siRNA-JAK2 inhibited the HPAEC to mesenchymal transition and the HPASMCs to myofibroblast transition and proliferation. JAK2 inhibition induced small PA relaxation in precision-cut lung slice experiments. PA relaxation was dependent of the large conductance calcium-activated potassium channel (BKCa). JAK2 inhibition activated BKCa channels and reduced intracellular Ca2+. JSI-124 1 mg/kg/day, reduced bleomycin-induced lung fibrosis, PA remodelling, right ventricular hypertrophy, PA hypertension and V/Q mismatching in rats. The animal studies followed the ARRIVE guidelines. CONCLUSIONS: JAK2 participates in PA remodelling and tension and may be an attractive target to treat IPF associated to PH.

The JAK2 pathway is activated in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is the most rapidly progressive and fatal fibrotic disorder, with no curative therapies. The signal transducer and activator of transcription 3 (STAT3) protein is activated in lung fibroblasts and alveolar type II cells (ATII), thereby contributing to lung fibrosis in IPF. Although activation of Janus kinase 2 (JAK2) has been implicated in proliferative disorders, its role in IPF is unknown. The aim of this study was to analyze JAK2 activation in IPF, and to determine whether JAK2/STAT3 inhibition is a potential therapeutic strategy for this disease. METHODS AND RESULTS: JAK2/p-JAK2 and STAT3/pSTAT3 expression was evaluated using quantitative real time-PCR, western blotting, and immunohistochemistry. Compared to human healthy lung tissue (n = 10) both proteins were upregulated in the lung tissue of IPF patients (n = 12). Stimulating primary ATII and lung fibroblasts with transforming growth factor beta 1 or interleukin (IL)-6/IL-13 activated JAK2 and STAT3, inducing epithelial to mesenchymal and fibroblast to myofibroblast transitions. Dual p-JAK2/p-STAT3 inhibition with JSI-124 or silencing of JAK2 and STAT3 genes suppressed ATII and the fibroblast to myofibroblast transition, with greater effects than the sum of those obtained using JAK2 or STAT3 inhibitors individually. Dual rather than single inhibition was also more effective for inhibiting fibroblast migration, preventing increases in fibroblast senescence and Bcl-2 expression, and ameliorating impaired autophagy. In rats administered JSI-124, a dual inhibitor of p-JAK2/p-STAT3, at a dose of 1 mg/kg/day, bleomycin-induced lung fibrosis was reduced and collagen deposition in the lung was inhibited, as were JAK2 and STAT3 activation and several markers of fibrosis, autophagy, senescence, and anti-apoptosis. CONCLUSIONS: JAK2 and STAT3 are activated in IPF, and their dual inhibition may be an attractive strategy for treating this disease.

MUC1 deficiency mediates corticosteroid resistance in chronic obstructive pulmonary disease.

BACKGROUND: Lung inflammation in COPD is poorly controlled by inhaled corticosteroids (ICS). Strategies to improve ICS efficacy or the search of biomarkers who may select those patients candidates to receive ICS in COPD are needed. Recent data indicate that MUC1 cytoplasmic tail (CT) membrane mucin can mediate corticosteroid efficacy in chronic rhinosinusitis. The objective of this work was to analyze the previously unexplored role of MUC1 on corticosteroid efficacy in COPD in vitro and in vivo models. METHODS: MUC1-CT expression was measured by real time PCR, western blot, immunohistochemistry and immunofluorescence. The inflammatory mediators IL-8, MMP9, GM-CSF and MIP3α were measured by ELISA. The effect of MUC1 on inflammation and corticosteroid anti-inflammatory effects was measured using cell siRNA in vitro and Muc1-KO in vivo animal models. RESULTS: MUC1-CT expression was downregulated in lung tissue, bronchial epithelial cells and lung neutrophils from smokers (n = 11) and COPD (n = 11) patients compared with healthy subjects (n = 10). MUC1 was correlated with FEV1% (ρ = 0.7479; p < 0.0001) in smokers and COPD patients. Cigarette smoke extract (CSE) decreased the expression of MUC1 and induced corticosteroid resistance in human primary bronchial epithelial cells and human neutrophils. MUC1 Gene silencing using siRNA-MUC1 impaired the anti-inflammatory effects of dexamethasone and reduced glucocorticoid response element activation. Dexamethasone promoted glucocorticoid receptor alpha (GRα) and MUC1-CT nuclear translocation and co-localization that was inhibited by CSE. Lung function decline and inflammation induced by lipopolysaccharide and cigarette smoke in Muc1 KO mice was resistant to dexamethasone. CONCLUSIONS: These results confirm a role for MUC1-CT mediating corticosteroid efficacy in COPD.

MUC4 impairs the anti-inflammatory effects of corticosteroids in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Current evidence suggests that membrane-tethered mucins could mediate corticosteroid efficacy, interacting with glucocorticoid receptor (GR) in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). Mucin 4 (MUC4)-tethered mucin is expressed in nasal polyp (NP) epithelial cells and upregulated under inflammatory conditions. Moreover, MUC4ß has the capacity to interact with other intracellular proteins. We hypothesized that MUC4 modulates corticosteroid efficacy of patients with CRSwNP. OBJECTIVE: We sought to analyze the role of MUC4 in corticosteroid effectiveness in different cohorts of patients with CRSwNP and elucidate the possible mechanisms involved. METHODS: Eighty-one patients with CRSwNP took oral corticosteroids for 15 days. Corticosteroid resistance was evaluated by using nasal endoscopy. Expression of MUC4 and MUC4ß was evaluated by means of real-time PCR, Western blotting, and immunohistochemistry. BEAS-2B knockdown with RNA interference for MUC4 (small interfering RNA [siRNA]-MUC4) was used to analyze the role of MUC4 in the anti-inflammatory effects of dexamethasone. RESULTS: Twenty-two patients had NPs resistant to oral corticosteroids. MUC4 expression was upregulated in these patients. In siRNA-MUC4 BEAS-2B airway epithelial cells dexamethasone produced higher anti-inflammatory effects, increased inhibition of phospho-extracellular signal-regulated kinase 1/2, increased mitogen-activated protein kinase phosphatase 1 expression, and increased glucocorticoid response element activation. Immunoprecipitation and immunofluorescence experiments revealed that MUC4ß forms a complex with GRα in the nuclei of NP epithelial cells from corticosteroid-resistant patients. CONCLUSION: MUC4ß participates in the corticosteroid resistance process, inhibiting normal GRα nuclear function. The high expression of MUC4 in patients with CRSwNP might participate in corticosteroid resistance.

Vascular effects of sildenafil in patients with pulmonary fibrosis and pulmonary hypertension: an ex vivo/in vitro study.

Sildenafil improves the 6-min walking distance in patients with idiopathic pulmonary fibrosis (IPF) and right-sided ventricular systolic dysfunction.We analysed the previously unexplored role of sildenafil on vasoconstriction and remodelling of pulmonary arteries from patients with IPF and pulmonary hypertension (PH) ex vivo Pulmonary arteries from 18 donors without lung disease, nine IPF, eight PH+IPF and four PH patients were isolated to measure vasodilator and anti-contractile effects of sildenafil in isometric organ bath. Ventilation/perfusion was explored in an animal model of bleomycin lung fibrosis.Sildenafil relaxed serotonin (5-HT) pre-contracted pulmonary arteries in healthy donors and IPF patients and, to a lesser extent, in PH+IPF and PH. Sildenafil inhibited 5-HT dose-response contraction curve mainly in PH+IPF and PH, but not in healthy donors. Sildenafil did not impair the ventilation/perfusion mismatching induced by bleomycin. Pulmonary arteries from PH+IPF patients showed a marked expression of phosphodiesterse-5 and extracellular matrix components. Sildenafil inhibited pulmonary artery endothelial and smooth muscle cell to mesenchymal transition by inhibition of extracellular regulated kinases 1 and 2 (ERK1/2) and SMAD3 phosphorylation.These results suggest an absence of direct relaxant effect and a prominent anti-contractile and anti-remodelling role of sildenafil in PH+IPF pulmonary arteries that could explain the beneficial effects of sildenafil in IPF with PH phenotype.

Non-neuronal cholinergic system contributes to corticosteroid resistance in chronic obstructive pulmonary disease patients.

BACKGROUND: Inhaled corticosteroid (ICS) with long-acting beta-2 agonists is a well-documented combination therapy for chronic obstructive pulmonary disease (COPD) based on its additive anti-inflammatory properties. By contrast, the recommendation of ICS in combination with long-acting muscarinic antagonist (LAMA) is not evidence-based. In this study, neutrophils obtained from COPD patients were used to compare the anti-inflammatory effects of aclidinium bromide (a long-acting muscarinic antagonist) with corticosteroids and their potential additive effect. METHODS: Human sputum and blood neutrophils were isolated from healthy individuals (n = 37), patients with stable COPD (n = 52) and those with exacerbated COPD (n = 16). The cells were incubated with corticosteroid fluticasone propionate (0.1 nM-1 µM), aclidinium bromide (0.1 nM-1 µM) or a combination thereof and stimulated with 1 µg of lipopolysaccharide/ml or 5 % cigarette smoke extract. Levels of the pro-inflammatory mediators interleukin-8, matrix metalloproteinase-9, CCL-5, granulocyte-macrophage colony-stimulating factor and interleukin-1ß were measured and the mechanisms of corticosteroid resistance evaluated at the end of the incubation. RESULTS: The non-neuronal cholinergic system was over-expressed in neutrophils from COPD patients, as evidenced by increases in the expression of muscarinic receptors (M2, M4 and M5), choline acetyltransferase and vesicular acetylcholine transporter. Aclidinium bromide demonstrated anti-inflammatory effects on neutrophils from COPD patients, reversing their resistance to corticosteroids. Additive effects of combined aclidinium bromide and fluticasone propionate in blocking M2 receptor levels, inhibiting phosphoinositide 3-kinase-δ and enhancing the glucocorticoid response element transcription factor were demonstrated and were accompanied by an increase in the corticosteroid-induced expression of anti-inflammatory-related genes. CONCLUSIONS: LAMAs potentiate the anti-inflammatory effects of corticosteroids in neutrophils from COPD patients in vitro, thus providing a scientific rationale for their use in combination with corticosteroids in the treatment of COPD.

Roflumilast improves corticosteroid resistance COPD bronchial epithelial cells stimulated with toll like receptor 3 agonist.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by chronic pulmonary inflammation punctuated by periods of viral exacerbations. Recent evidence suggests that the combination of roflumilast with corticosteroids may improve the compromised anti-inflammatory properties of corticosteroids in COPD. We analyzed differential and combination anti-inflammatory effects of dexamethasone and roflumilast N-oxide in human bronchial epithelial cells (HBECs) stimulated with viral toll like receptor (TLR) agonists. METHODS: Lung tissue and HBECs were isolated from healthy (n = 15), smokers (n = 12) and smokers with COPD (15). TLR3 expression was measured in lung tissue and in HBECs. IL-8 secretion was measured in cell cultures after TLR3 stimulation with poly I:C 10 µg/mL. RESULTS: We found that TLR3 expression was increased by 1.95 fold (protein) and 2.5 fold (mRNA) in lung tissues from smokers with COPD and inversely correlated with lung function. The TLR3 agonist poly I:C 10 µg/mL increased the IL-8 release in HBECs that was poorly inhibited by dexamethasone in smokers (24.5%) and smokers with COPD (21.6%). In contrast, roflumilast showed similar inhibitory effects on IL-8 release in healthy (58.8%), smokers (56.6%) and smokers with COPD (50.5%). The combination of roflumilast N-oxide and dexamethasone showed additive inhibitory effects. Mechanistically, roflumilast N-oxide when combined with dexamethasone increased the expression of MKP1, and enhanced the inhibitory effects on phospho-p38, AP1 and NFκB activities which may explain the additive anti-inflammatory effects. CONCLUSIONS: Altogether, our data provide in vitro evidence for a possible clinical utility to add roflumilast on top of inhaled corticosteroid in COPD.

Arterial and venous endothelia display differential functional fractalkine (CX3CL1) expression by angiotensin-II.

OBJECTIVE: Angiotensin-II (Ang-II) promotes the interaction of mononuclear cells with arterioles and neutrophils with postcapillary venules. To investigate the mechanisms underlying this dissimilar response, the involvement of fractalkine (CX(3)CL1) was explored. METHODS AND RESULTS: Enhanced CX(3)CL1 expression was detected in both cremasteric arterioles and postcapillary venules 24 hours after Ang-II intrascrotal injection. Arteriolar leukocyte adhesion was the unique parameter significantly reduced (83%) in animals lacking CX(3)CL1 receptor (CX(3)CR1). Human umbilical arterial and venous endothelial cell stimulation with 1 µmol/L Ang-II increased CX(3)CL1 expression, yet neutralization of CX(3)CL1 activity only significantly inhibited Ang-II-induced mononuclear cell-human umbilical arterial endothelial cell interactions (73%) but not with human umbilical venous endothelial cells. The use of small interfering RNA revealed the involvement of tumor necrosis factor-α in Ang-II-induced CX(3)CL1 upregulation and mononuclear cell arrest. Nox5 knockdown with small interfering RNA or pharmacological inhibition of extracellular signal-regulated kinases1/2, p38 mitogen-activated protein kinase, and nuclear factor-κB also abolished these responses. Finally, when human umbilical arterial endothelial cells were costimulated with Ang-II, tumor necrosis factor-α, and interferon-γ, CX(3)CL1 expression and mononuclear cell adhesiveness were more pronounced than when each stimulus was provided alone. CONCLUSIONS: These results suggest that Ang-II induces functional CX(3)CL1 expression in arterial but not in venous endothelia. Thus, targeting endothelial CX(3)CL1-mononuclear leukocyte CX(3)CR1 interactions may constitute a new therapeutic strategy in the treatment of Ang-II-associated cardiovascular diseases.

Retinoid X receptor agonists impair arterial mononuclear cell recruitment through peroxisome proliferator-activated receptor-γ activation.

Mononuclear cell migration into the vascular subendothelium constitutes an early event of the atherogenic process. Because the effect of retinoid X receptor (RXR)α on arterial mononuclear leukocyte recruitment is poorly understood, this study investigated whether RXR agonists can affect this response and the underlying mechanisms involved. Decreased RXRα expression was detected after 4 h stimulation of human umbilical arterial endothelial cells with TNF-α. Interestingly, under physiological flow conditions, TNF-α-induced endothelial adhesion of human mononuclear cells was concentration-dependently inhibited by preincubation of the human umbilical arterial endothelial cells with RXR agonists such as bexarotene or 9-cis-retinoid acid. RXR agonists also prevented TNF-α-induced VCAM-1 and ICAM-1 expression, as well as endothelial growth-related oncogene-α and MCP-1 release. Suppression of RXRα expression with a small interfering RNA abrogated these responses. Furthermore, inhibition of MAPKs and NF-κB pathways were involved in these events. RXR agonist-induced antileukocyte adhesive effects seemed to be mediated via RXRα/peroxisome proliferator-activated receptor (PPAR)γ interaction, since endothelial PPARγ silencing abolished their inhibitory responses. Furthermore, RXR agonists increased RXR/PPARγ interaction, and combinations of suboptimal concentrations of both nuclear receptor ligands inhibited TNF-α-induced mononuclear leukocyte arrest by 60-65%. In vivo, bexarotene dose-dependently inhibited TNF-α-induced leukocyte adhesion to the murine cremasteric arterioles and decreased VCAM-1 and ICAM-1 expression. Therefore, these results reveal that RXR agonists can inhibit the initial inflammatory response that precedes the atherogenic process by targeting different steps of the mononuclear recruitment cascade. Thus, RXR agonists may constitute a new therapeutic tool in the control of the inflammatory process associated with cardiovascular disease.

Comparison of Different Doses of Oral and Ocular Propranolol for Retinopathy of Prematurity: A Network Meta-Analysis.

OBJECTIVE: The efficacy and safety of propranolol for retinopathy of prematurity (ROP) remain under debate. This network meta-analysis (NMA) focuses on whether a ranking may be established for different dose levels of propranolol as treatment of ROP in terms of stage progression as the primary outcome, with appearance of plus disease and need for anti-vascular endothelial growth factors (anti-VEGFs) or laser therapy as secondary endpoints. METHODS: Fourteen studies (10 randomised controlled trials, three single-arm trials and one retrospective observational study) of 474 patients treated with oral or ocular propranolol were retrieved from databases up to April 2024. Meta-insight and model-based NMA were undertaken to evaluate the propranolol dose-response relationship. Studies were evaluated for model fit, risk of bias and Confidence of evidence In Network Meta-Analysis (CINeMA). Effect sizes were determined as odds ratio (OR) with 95% credible interval (CrI). RESULTS: Bayesian analysis showed a trend towards improved effects for propranolol given at late stages (stages 2-3; S23) of ROP progression compared with its administration at earlier stages (stages 0-1; S01). OR values for oral propranolol 1.5 and 2 mg/kg/day given at S23 were 0.13 (95% CrI 0.04-0.37) and 0.16 (95% CrI 0.04-0.61), respectively, while given at S01 were 0.28 (95% CrI 0.02-2.96) and 0.78 (95% CrI 0.14-4.43), respectively. Similarly, OR of eye propranolol 0.2% at S23 was 0.37 (95% CrI 0.09-1.00) versus an S01 OR of 0.64 (95% CrI 0.21-2.04). Surface under the cumulative ranking curve (SUCRA) analyses confirmed best probability values for oral propranolol 1.5-2 mg/kg followed by eye propranolol 0.2%, all at S23. Model-based NMA showed nonlinearity in the dose-response for oral propranolol with a trend to greater maximal effect for its administration at late versus early stages. For secondary endpoints, lower risk values were found with oral propranolol 1.5 mg/kg/day at S23 for progression to plus disease (OR 0.14; 95% CrI 0.02-0.84) and need for anti-VEGFs (OR 0.23; 95% CrI 0.05-0.93) and laser (OR 0.16; 95% CrI 0.02-1.10) therapies also followed by eye propranolol 0.2%, and a similar profile was obtained with SUCRA analysis. Lower doses (0.5-1.0 mg/kg/day) of oral propranolol retained efficacy. Threat of adverse events was estimated as risk difference versus control with no difference for eye propranolol 0.2% and oral propranolol 0.5 mg/kg/day, modest increases of risk for oral propranolol 1.0 and 1.5 mg/kg/day and the highest risk difference for oral propranolol 2.0 mg/kg/day (0.06; 95% CI -0.01 to 0.13). CONCLUSION: A diminished risk of disease progression and need for additional treatment was obtained with propranolol in ROP, but safety is a potential concern. Propranolol eye micro-drops (0.2%) can be as efficacious as oral propranolol. Nonetheless, the evidence is limited due to the paucity and quality of the available studies.

Comparison of different agents and doses of anti-vascular endothelial growth factors (aflibercept, bevacizumab, conbercept, ranibizumab) versus laser for retinopathy of prematurity: A network meta-analysis.

Laser photocoagulation (LPC) and/or intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections constitute the current standard treatment for retinopathy of prematurity (ROP). This network meta-analysis focus on whether a ranking of interventions may be established for different dose levels of intravitreal injection of anti-VEGF agents (aflibercept, bevacizumab, conbercept, ranibizumab) as primary treatments for ROP versus laser in terms of retreatment rate as primary outcome, and time to retreatment and refractive error as secondary endpoints, since best anti-VEGF dosage remains under debate. Sixty-eight studies (15 randomized control trials and 53 nonrandomized studies) of 12,356 eyes of 6445 infants were retrieved from databases (2005 Jan. - 2023 June). Studies were evaluated for model fit, risk of bias and confidence of evidence in Network Meta-Analysis (CINeMA). Bayesian NMA showed that anti-VEGF drugs were not inferior to laser in terms of retreatment rate. For intravitreal bevacizumab (IVB), doses half of the conventional infant dose showed a low risk of retreatment rate (risk ratio (RR) of 1.43; 95% credible interval (CrI): 0.508, 4.03). On probability ranking as surface under the cumulative ranking curve (SUCRA) plot, half dose of bevacizumab had a better position than conventional and augmented (1.2-2 times the regular dose) doses. A similar probability trend was observed for half vs. conventional doses of aflibercept and ranibizumab. Conventional infant dose of conbercept showed the lowest risk for retreatment (RR 0.846; 95% CrI: 0.245, 2.91). For secondary endpoints, lower doses of anti-VEGF agents were associated with shorter times to retreatment. The largest changes were noted for the augmented doses of bevacizumab and ranibizumab (0.3 mg) with means of 14.1 weeks (95% CrI: 6.65, 21.6) and 12.8 weeks (95% CrI: 3.19, 20.9), respectively. Finally, NMA demonstrated better refractive profile for anti-VEGF than laser therapy, especially for the conventional infant doses of bevacizumab and ranibizumab which exhibited a significantly better refractive profile than LPC, with mean differences of 1.67 (spherical equivalent - diopters) (95% CrI: 0.705, 2.67) and 2.19 (95% CrI: 0.782, 3.59), respectively. In the SUCRA plots, LPC had a markedly different position with a higher probability for myopia. Further clinical trials comparing different intravitreal doses of anti-VEGF agents are needed, but our findings suggest that low doses of these drugs retain efficacy and may reduce ocular and systemic undesired events.

Key role of activated platelets in the enhanced adhesion of circulating leucocyte-platelet aggregates to the dysfunctional endothelium in early-stage COPD.

Background: Chronic obstructive pulmonary disease (COPD), usually caused by long-term tobacco smoking, is independently associated with systemic inflammation. However, little is known about the systemic inflammatory status of patients with early-stage COPD (classified as GOLD 1) and long-term smokers with normal lung function (LF). Here, we characterised the early changes in the associated inflammatory state in patients with GOLD 1 and in long-term smokers with normal LF. Methods: Fresh blood samples from 27 patients with GOLD 1, 27 long-term smokers and 14 non-smokers were analysed. Results: Ex vivo blood analysis revealed greater leucocyte-platelet adhesion to TNFα-stimulated pulmonary endothelium in patients with GOLD 1 than in smokers and non-smokers. In addition, platelet reactivity (platelet count and activation, and fibrinogen levels) and the frequency of leucocyte-platelet aggregates were higher in the GOLD 1 group than in the other groups. Some of these findings correlated with the severity of lung dysfunction, while platelet hyperactivity correlated positively with leucocyte-platelet adhesion. The GOLD 1 group also had a higher Th17/Treg ratio and higher circulating levels of IL-17C and C-reactive protein than the other groups. However, long-term smokers also had higher leucocyte counts and activation, and higher plasma levels of TNFα and IL-6 than non-smokers. Conclusion: Our data suggest that the altered inflammatory parameters in long-term smokers may represent early biomarkers of COPD. Accordingly, peripheral immune monitoring based on the above parameters may be useful to prevent disease progression in long-term smokers with normal LF and early COPD.

Critical role of fractalkine (CX3CL1) in cigarette smoke-induced mononuclear cell adhesion to the arterial endothelium.

BACKGROUND: Cigarette smoking is an important risk factor for the development of cardiovascular disease, yet the pathways through which this may operate are poorly understood. Therefore, the mechanism underlying cigarette smoke (CS)-induced arterial endothelial dysfunction and the potential link with fractalkine/CX(3)CL1 upregulation were investigated. METHODS AND RESULTS: Stimulation of human arterial umbilical endothelial cells (HUAECs) with pathophysiological concentrations of CS extract (1% CSE) increased CX(3)CL1 expression. Neutralisation of CX(3)CL1 activity under dynamic flow conditions significantly inhibited CSE-induced mononuclear cell adhesion to HUAECs (67%). The use of small interfering RNA (siRNA) revealed that nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 5 (Nox5) but not Nox2 or Nox4 is the main NADPH isoform involved in CSE-induced CX(3)CL1 upregulation and mononuclear cell arrest. Knock down of HUAEC tumour necrosis factor α expression with siRNA or pharmacological inhibition of p38 mitogen-activated protein kinase and nuclear factor κB also abolished these responses. Interestingly, circulating monocytes and lymphocytes from patients with chronic obstructive pulmonary disease (COPD) (n=29) versus age-matched controls (n=23) showed CX(3)CR1overexpression. Furthermore, CX(3)CL1 neutralisation dramatically diminished their enhanced adhesiveness to CSE-stimulated HUAECs. Finally, when animals were exposed for 3 days to CS, a mild inflammatory response in the lung was observed which was accompanied by enhanced CX(3)CL1 expression in the cremasteric arterioles, an organ distant from the lung. CS exposure resulted in increased leukocyte-arteriolar endothelial cell adhesion which was significantly reduced (51%) in animals lacking CX(3)CL1 receptor (CX(3)CR1). CONCLUSIONS: These results suggest that CS induces functional CX(3)CL1 expression in arterial endothelium and leukocytes from patients with COPD show increased CX(3)CL1-dependent adhesiveness. Therefore, targeting the CX(3)CL1/CX(3)CR1 axis might prevent COPD-associated cardiovascular disorders.

Aclidinium inhibits cigarette smoke-induced lung fibroblast-to-myofibroblast transition.

Cigarette smoking contributes to lung remodelling in chronic obstructive pulmonary disease (COPD). As part of this remodelling, peribronchiolar fibrosis is observed in the small airways of COPD patients and contributes to airway obstruction. Fibroblast-to-myofibroblast transition is a key step in peribronchiolar fibrosis formation. This in vitro study examined the effect of cigarette smoke on bronchial fibroblast-to-myofibroblast transition, and whether aclidinium bromide inhibits this process. Human bronchial fibroblasts were incubated with aclidinium bromide (10(-9)-10(-7) M) and exposed to cigarette smoke extract. Collagen type I and α-smooth muscle actin (α-SMA) expression were measured by real-time PCR and Western blotting, as myofibroblast markers. Intracellular reactive oxygen species, cyclic AMP (cAMP), extracellular signal-regulated kinase (ERK)1/2 and choline acetyltransferase were measured as intracellular signalling mediators. Cigarette smoke-induced collagen type I and α-SMA was mediated by the production of reactive oxygen species, the depletion of intracellular cAMP and the increase of ERK1/2 phosphorylation and choline acetyltransferase. These effects could be reversed by treatment with the anticholinergic aclidinium bromide, by silencing the mRNA of muscarinic receptors M1, M2 or M3, or by the depletion of extracellular acetylcholine by treatment with acetylcholinesterase. A non-neuronal cholinergic system is implicated in cigarette smoke-induced bronchial fibroblast-to-myofibroblast transition, which is inhibited by aclidinium bromide.

Aclidinium inhibits human lung fibroblast to myofibroblast transition.

BACKGROUND: Fibroblast to myofibroblast transition is believed to contribute to airway remodelling in lung diseases such as asthma and chronic obstructive pulmonary disease. This study examines the role of aclidinium, a new long-acting muscarinic antagonist, on human fibroblast to myofibroblast transition. METHODS: Human bronchial fibroblasts were stimulated with carbachol (10(-8) to 10(-5) M) or transforming growth factor-ß1 (TGF-ß1; 2 ng/ml) in the presence or absence of aclidinium (10(-9) to 10(-7) M) or different drug modulators for 48 h. Characterisation of myofibroblasts was performed by analysis of collagen type I and α-smooth muscle actin (α-SMA) mRNA and protein expression as well as α-SMA microfilament immunofluorescence. ERK1/2 phosphorylation, RhoA-GTP and muscarinic receptors (M) 1, 2 and 3 protein expression were determined by western blot analysis and adenosine 3'-5' cyclic monophosphate levels were determined by ELISA. Proliferation and migration of fibroblasts were also assessed. RESULTS: Collagen type I and α-SMA mRNA and protein expression, as well as percentage α-SMA microfilament-positive cells, were upregulated in a similar way by carbachol and TGF-ß1, and aclidinium reversed these effects. Carbachol-induced myofibroblast transition was mediated by an increase in ERK1/2 phosphorylation, RhoA-GTP activation and cyclic monophosphate downregulation as well as by the autocrine TGF-ß1 release, which were effectively reduced by aclidinium. TGF-ß1 activated the non-neuronal cholinergic system. Suppression of M1, M2 or M3 partially prevented carbachol- and TGF-ß1-induced myofibroblast transition. Aclidinium dose-dependently reduced fibroblast proliferation and migration. CONCLUSION: Aclidinium inhibits human lung fibroblast to myofibrobast transition.

Sphingosine-1-phosphate is increased in patients with idiopathic pulmonary fibrosis and mediates epithelial to mesenchymal transition.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is characterised by the aberrant epithelial to mesenchymal transition (EMT) and myofibroblast accumulation. Sphingosine-1-phosphate (S1P) and sphingosine kinase 1 (SPHK1) have been implicated in lung myofibroblast transition, but their role in EMT and their expression in patients with IPF is unknown. METHODS AND RESULTS: S1P levels were measured in serum (n=27) and bronchoalveolar lavage (BAL; n=15) from patients with IPF and controls (n=30 for serum and n=15 for BAL studies). SPHK1 expression was measured in lung tissue from patients with IPF (n=12) and controls (n=15). Alveolar type II transformation into mesenchymal cells was studied in response to S1P (10(-9)-10(-5) M). The median (IQR) of S1P serum levels was increased in patients with IPF (1.4 (0.4) µM) versus controls (1 (0.26) µM; p<0.0001). BAL S1P levels were increased in patients with IPF (1.12 (0.53) µM) versus controls (0.2 (0.5); p<0.0001) and correlated with diffusion capacity of the lung for carbon monoxide, forced expiratory volume in 1 s and forced vital capacity (Spearman's r=-0.87, -0.72 and -0.68, respectively) in patients with IPF. SPHK1 was upregulated in lung tissue from patients with IPF and correlated with α-smooth muscle actin, vimentin and collagen type I (Spearman's r=0.82, 0.85 and 0.72, respectively). S1P induced EMT in alveolar type II cells by interacting with S1P(2) and S1P(3), as well as by the activation of p-Smad3, RhoA-GTP, oxidative stress and transforming growth factor-ß1 (TGF-ß1) release. Furthermore, TGF-ß1-induced EMT was partially conducted by the S1P/SPHK1 activation, suggesting crosstalk between TGF-ß1 and the S1P/SPHK1 axis. CONCLUSIONS: S1P is elevated in patients with IPF, correlates with the lung function and mediates EMT.

Pharmacological characterization of abediterol, a novel inhaled ß(2)-adrenoceptor agonist with long duration of action and a favorable safety profile in preclinical models.

Abediterol is a novel potent, long-acting inhaled ß(2)-adrenoceptor agonist in development for the treatment of asthma and chronic obstructive pulmonary disease. Abediterol shows subnanomolar affinity for the human ß(2)-adrenoceptor and a functional selectivity over ß(1)-adrenoceptors higher than that of formoterol and indacaterol in both a cellular model with overexpressed human receptors and isolated guinea pig tissue. Abediterol is a full agonist at the human ß(2)-adrenoceptor (E(max) = 91 ± 5% of the maximal effect of isoprenaline). The potency and onset of action that abediterol shows in isolated human bronchi (EC(50) = 1.9 ± 0.4 nM; t½ onset = 7-10 min) is not significantly different from that of formoterol, but its duration of action (t½ ∼ 690 min) is similar to that of indacaterol. Nebulized abediterol inhibits acetylcholine-induced bronchoconstriction in guinea pigs in a concentration-dependent manner, with higher potency and longer duration of action (t½ = 36 h) than salmeterol (t½ = 6 h) and formoterol (t½ = 4 h) and similar duration of action to indacaterol up to 48 h. In dogs, the bronchoprotective effect of abediterol is more sustained than that of salmeterol and indacaterol at doses without effects on heart rate, thus showing a greater safety margin (defined as the ratio of dose increasing heart rate by 5% and dose inhibiting bronchospasm by 50%) than salmeterol, formoterol, and indacaterol (5.6 versus 3.3, 2.2, and 0.3, respectively). In conclusion, our results suggest that abediterol has a preclinical profile for once-daily dosing in humans together with a fast onset of action and a favorable cardiovascular safety profile.

Trans- but not cis-resveratrol impairs angiotensin-II-mediated vascular inflammation through inhibition of NF-κB activation and peroxisome proliferator-activated receptor-gamma upregulation.

Angiotensin II (Ang-II) displays inflammatory activity and is implicated in several cardiovascular disorders. This study evaluates the effect of cis- and trans (t)-resveratrol (RESV) in two in vivo models of vascular inflammation and identifies the cardioprotective mechanisms that underlie them. In vivo, Ang-II-induced arteriolar leukocyte adhesion was inhibited by 71% by t-RESV (2.1 mg/kg, i.v.), but was not affected by cis-RESV. Because estrogens influence the rennin-angiotensin system, chronic treatment with t-RESV (15 mg/kg/day, orally) inhibited ovariectomy-induced arteriolar leukocyte adhesion by 81%, partly through a reduction of cell adhesion molecule (CAM) expression and circulating levels of cytokine-induced neutrophil chemoattractant, MCP-1, and MIP-1alpha. In an in vitro flow chamber system, t-RESV (1-10 microM) undermined the adhesion of human leukocytes under physiological flow to Ang-II-activated human endothelial cells. These effects were accompanied by reductions in monocyte and endothelial CAM expression, chemokine release, phosphorylation of p38 MAPK, and phosphorylation of the p65 subunit of NF-kappaB. Interestingly, t-RESV increased the expression of peroxisome proliferator-activated receptor-gamma in human endothelial and mononuclear cells. These results demonstrate for the first time that the in vivo anti-inflammatory activity of RESV is produced by its t-RESV, which possibly interferes with signaling pathways that cause the upregulation of CAMs and chemokine release. Upregulation of proliferator-activated receptor-gamma also appears to be involved in the cardioprotective effects of t-RESV. In this way, chronic administration of t-RESV may reduce the systemic inflammatory response associated with the activation of the rennin-angiotensin system, thereby decreasing the risk of further cardiovascular disease.