P38 MAPK and glucocorticoid receptor crosstalk in bronchial epithelial cells

Abstract

p38 MAPK inhibition may have additive and synergistic anti-inflammatory effects when used with corticosteroids. We investigated crosstalk between p38 MAPK inhibitors and corticosteroids in bronchial epithelial cells to investigate synergistic effects on cytokine production and the molecular mechanisms involved. Effects of the p38 MAPK inhibitor BIRB-796 and dexamethasone alone and in combination on LPS, polyI:C or TNFα -induced IL-6, CXCL8 and RANTES were assessed in 16HBEs (human epithelial cell line) and on TNFα-induced IL-6 and CXCL8 in primary human epithelial cells from asthma patients and healthy controls. 16HBEs were used to assess effects of BIRB-796 alone and in combination with dexamethasone on glucocorticoid receptor (GR) activity by reporter gene assay, expression of GR target genes and nuclear localisation using Western blot. The effects of BIRB-796 on TNFα stimulated phosphorylation of p38 MAPK and GR at serine (S) 226 by Western blot. Epithelial levels of phosphorylated p38 MAPK and GR S226 were determined by immunohistochemistry in bronchial biopsies from asthma patients and healthy controls. BIRB-796 in combination with dexamethasone increased inhibition of cytokine production in a synergistic manner. Combination treatment significantly increased GR nuclear localisation compared to dexamethasone alone. BIRB-796 inhibited TNFα-induced p38 MAPK and GR S226 phosphorylation. Phosphorylated GR S226 and p38 MAPK levels were increased in bronchial epithelium of more severe asthma patients. Molecular crosstalk exists between p38 MAPK activation and GR function in human bronchial epithelial cells, which alters GR activity. Combining a p38 MAPK inhibitor and a corticosteroid may demonstrate therapeutic potential in severe asthma.

Key messages

• Combination of corticosteroid and p38 inhibitor in human bronchial epithelial cells

• Combination increased cytokine inhibition synergistically and nuclear GR

• p38 MAPK inhibition reduced TNFα-induced phosphorylation of GR at S226 but not S211

• Phosphorylated GRS226 and p38 is increased in bronchial epithelium in severe asthma

• Combining a p38 inhibitor and a corticosteroid may be effective in asthma treatment

Electronic supplementary material

The online version of this article (10.1007/s00109-020-01873-3) contains supplementary material, which is available to authorized users.

Knowledge and attitudes of Irish Mental Health Professionals to the concept of recovery from mental illness - five years later

WHAT IS KNOWN ABOUT THE SUBJECT?: The Advancing Recovery in Ireland (ARI) project (Health Service Executive, 2012) promotes recovery-orientated services. A previous study of Irish mental health practitioners (Cleary & Dowling ) identified the need to improve knowledge and attitudes towards recovery. To facilitate implementation of ARI and monitor progress, this study provided a 'benchmark' of current knowledge and attitudes to recovery. WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE?: The study provides important baseline information on recovery knowledge and attitudes which can be used to assess the impact of the ARI Project. It also provides valuable information that can be compared to recovery approaches employed in other countries. Despite the increased emphasis on recovery in Ireland, knowledge and attitudes of health care practitioners towards recovery remain relatively unchanged between 2007 and 2013. Working in dual settings, being a non-nurse, and training was associated with better RKI scores. Training appears to be the strongest factor in predicting better recovery knowledge. The findings suggest that knowledge levels and attitude changes following education may not be sustained over time and ongoing training may be required. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: There is considerable scope to improve recovery knowledge. Key recommendations include the need for more recovery training, evaluate whether training translates into clinical practice, using 'Recovery Champions', introducing peer support workers and developing local policies and protocols to support recovery practice.

ABSTRACT

Introduction A study of Irish mental health practitioners (Cleary & Dowling ) identified the need to improve knowledge and attitudes towards recovery. This led to the Advancing Recovery in Ireland Project (ARI) which promoted recovery-orientated services and a need to 'benchmark' progress. There is little evidence regarding the types of educational interventions that maintain positive recovery knowledge and attitudes in providers. Aim The study assessed current knowledge and attitudes to recovery. Methods The methodology of Cleary & Dowling () was replicated. A survey was administered to practitioners (n = 337) using the adapted Recovery Knowledge Inventory (RKI) (Cleary & Dowling ). Results No significant differences were found in recovery scores compared to Cleary & Dowling () or by level of experience. Working in dual settings, being a non-nurse, and training was associated with better recovery scores. Significantly more respondents had received training in recovery (40% versus 23%) compared to Cleary & Dowling (). Training appears to be the strongest factor predicting better recovery knowledge. Conclusions There is considerable scope to improve recovery knowledge. Key recommendations include the need for more recovery training, using 'Recovery Champions', introducing peer support workers and developing local policies and protocols to support recovery working.

Increased phosphorylated p38 mitogen-activated protein kinase in COPD lungs

The p38 mitogen-activated protein kinase (MAPK) pathway is upregulated in chronic obstructive pulmonary disease (COPD). To date, dual labelling to identify cell-type-specific presence of phosphorylated (phospho-)p38 MAPK has not been carried out. Phospho-p38 MAPK was quantified in a variety of cell types in the lung tissue of 20 COPD patients, 12 smokers and 12 nonsmokers using immunohistochemistry. Paired blood and sputum neutrophils (from seven subjects with COPD), and CD8 and epithelial cells (from three subjects with COPD) were cultured with a p38 MAPK inhibitor. Supernatant tumour necrosis factor-α and CXCL8 levels were analysed by ELISA. Sputum and blood neutrophil cytospins were analysed for phospho-p38 MAPK. Phospho-p38 MAPK was increased in bronchial epithelial cells, macrophages and CD20+ and CD8+ lymphocytes in COPD lungs. Sputum and lung tissue neutrophils were devoid of phospho-p38 in all patient groups. The p38 MAPK inhibitor SB100 attenuated pro-inflammatory mediator release in COPD lung CD8 cells and airway epithelia, but there was no effect on COPD sputum neutrophils. Our data indicate cell-specific anti-inflammatory effects of p38 MAPK inhibition in the lung.

Reduced glucocorticoid receptor expression and function in airway neutrophils

Chronic Obstructive Pulmonary Disease (COPD) is a glucocorticoid resistant condition characterised by airway neutrophilia. Reduced glucocorticoid receptor (GR) expression in COPD airway neutrophils may be a mechanism that contributes to glucocorticoid resistance. Our objective was to investigate the expression and function of GR within COPD airway neutrophils. Dual-label immunofluorescence was used to analyse airway neutrophil expression of GR within peripheral lung tissue samples (11 COPD patients, 7 healthy non-smokers [NS]) and induced sputum (7 COPD patients, 7 NS). TNFα and CXCL8 release were measured in neutrophils isolated from induced sputum and peripheral blood (7 COPD patients) in the presence of dexamethasone. In lung tissue, GR was abundantly expressed in macrophages and lymphocytes, but very low expression was observed in neutrophils (means 6.8% and 4.3% in COPD patients and NS respectively). Similarly low expression was observed in sputum neutrophils (means 3.8% and 6.9% in COPD patients and NS respectively). In contrast, GR was expressed by 100% of blood neutrophils. Dexamethasone had less suppressive effect on TNFα and CXCL8 production in vitro by neutrophils from induced sputum compared to neutrophils from paired blood samples. Airway neutrophils have low expression of GR in both COPD patients and controls. The effects of glucocorticoids on cytokine production from airway neutrophils are reduced. Increased numbers of airway neutrophils lacking GR may contribute to glucocorticoid resistance in COPD patients.