Pulmonary Hypertension Exacerbated by Nintedanib Administration for Idiopathic Pulmonary Fibrosis

Pulmonary Hypertension in the Course of Interstitial Lung Diseases-A Personalised Approach Is Needed to Identify a Dominant Cause and Provide an Effective Therapy

The prevalence of pulmonary hypertension (PH) complicating interstitial lung diseases (ILDs) is 3.5-15% at an early stage, and up to 90% in ILD patients listed for lung transplantation. In addition, other types of PH may occur in patients with ILDs due to concomitant conditions. Therefore, any significant PH occurring in the setting of ILD requires a proper differential workup. PH increases morbidity and mortality in ILDs. The pathomechanisms underlying PH due to ILD (PH-ILD) are not fully known, and there is no straightforward correlation between the presence or severity of PH-ILD and the severity of ILD. Severe PH in mild ILD without other explanatory causes constitutes a dilemma of differentiating between PH due to ILD and pulmonary arterial hypertension coexisting with ILDs. The heterogeneity and poor prognosis of patients with ILDs coexisting with PH necessitate an individualised approach to the management of this condition. This review presents recent advances in understanding and treatment options in PH-ILD. It also addresses practical issues, such as when to suspect and how to screen for PH in ILD, what are the indications for right heart catheterisation, and how to approach an individual ILD patient to determine the dominant PH cause and apply adequate management.

The Role of JAK/STAT Molecular Pathway in Vascular Remodeling Associated with Pulmonary Hypertension

Pulmonary hypertension is defined as a group of diseases characterized by a progressive increase in pulmonary vascular resistance (PVR), which leads to right ventricular failure and premature death. There are multiple clinical manifestations that can be grouped into five different types. Pulmonary artery remodeling is a common feature in pulmonary hypertension (PH) characterized by endothelial dysfunction and smooth muscle pulmonary artery cell proliferation. The current treatments for PH are limited to vasodilatory agents that do not stop the progression of the disease. Therefore, there is a need for new agents that inhibit pulmonary artery remodeling targeting the main genetic, molecular, and cellular processes involved in PH. Chronic inflammation contributes to pulmonary artery remodeling and PH, among other vascular disorders, and many inflammatory mediators signal through the JAK/STAT pathway. Recent evidence indicates that the JAK/STAT pathway is overactivated in the pulmonary arteries of patients with PH of different types. In addition, different profibrotic cytokines such as IL-6, IL-13, and IL-11 and growth factors such as PDGF, VEGF, and TGFβ1 are activators of the JAK/STAT pathway and inducers of pulmonary remodeling, thus participating in the development of PH. The understanding of the participation and modulation of the JAK/STAT pathway in PH could be an attractive strategy for developing future treatments. There have been no studies to date focused on the JAK/STAT pathway and PH. In this review, we focus on the analysis of the expression and distribution of different JAK/STAT isoforms in the pulmonary arteries of patients with different types of PH. Furthermore, molecular canonical and noncanonical JAK/STAT pathway transactivation will be discussed in the context of vascular remodeling and PH. The consequences of JAK/STAT activation for endothelial cells and pulmonary artery smooth muscle cells’ proliferation, migration, senescence, and transformation into mesenchymal/myofibroblast cells will be described and discussed, together with different promising drugs targeting the JAK/STAT pathway in vitro and in vivo.

Idiopathic pulmonary fibrosis and pulmonary hypertension: Heracles meets the Hydra

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease where the additional presence of pulmonary hypertension (PH) reduces survival. In particular, the presence of coexistent pulmonary vascular disease in patients with advanced lung parenchymal disease results in worse outcomes than either diagnosis alone. This is true with respect to the natural histories of these diseases, outcomes with medical therapies, and even outcomes following lung transplantation. Consequently, there is a striking need for improved treatments for PH in the setting of IPF. In this review, we summarize existing therapies from the perspective of molecular mechanisms underlying lung fibrosis and vasoconstriction/vascular remodelling and discuss potential future targets for pharmacotherapy. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.1/issuetoc.

Airway-centered Fibroelastosis Accompanied by Subpleural Lesions of Unknown Cause in a Young Man Who Later Developed Pulmonary Hypertension

A 26-year-old man with a history of bronchial asthma was found to have high-density shadows along the bronchovascular bundle and in the subpleural area on computed tomography of the chest. Surgical lung biopsy specimens from the right S⁵ showed fibroelastosis in the subpleural and central airway area with alveolar destruction. He was diagnosed with airway-centered fibroelastosis of unknown cause after multidisciplinary discussions. The patient developed pulmonary hypertension and died 6 years later. The patient was younger in comparison to patients in earlier reports and had more obvious subpleural fibroelastic lesions in the upper lobes than in previously described cases.

Emergency myelopoiesis contributes to immune cell exhaustion and pulmonary vascular remodelling

BACKGROUND AND PURPOSE

Pulmonary hypertension (PH) secondary to chronic lung disease (World Health Organization Group 3 PH) is deadly, with lung transplant being the only available long-term treatment option. Myeloid-derived cells are known to affect progression of both pulmonary fibrosis and PH, although the mechanism of action is unknown. Therefore, we investigated the effect of myeloid cell proliferation induced by emergency myelopoiesis on development of PH and therapy directed against programmed death-ligand 1 (PD-L1), expressed by myeloid cells in prevention of pulmonary vascular remodelling.

EXPERIMENTAL APPROACH

LysM.Cre-DTR ("mDTR") mice were injected with bleomycin (0.018 U·g^-1 , i.p.) while receiving either vehicle or diphtheria toxin (DT; 100 ng, i.p.) to induce severe PH. Approximately 4 weeks after initiation of bleomycin protocol, right ventricular pressure measurements were performed and tissue samples collected for histologic assessment. In a separate experiment, DT-treated mice were given anti-PD-L1 antibody (αPD-L1; 500 μg, i.p.) preventive treatment before bleomycin administration.

KEY RESULTS

Mice undergoing induction of emergency myelopoiesis displayed more severe PH, right ventricular remodelling and pulmonary vascular muscularization compared to controls, without a change in lung fibrosis. This worsening of PH was associated with increased pulmonary myeloid-derived suppressor cell (MDSC), particularly polymorphonuclear MDSC (PMN-MDSC). Treatment with αPD-L1 normalized pulmonary pressures. PD-L1 expression was likewise found to be elevated on circulating PMN-MDSC from patients with interstitial lung disease and PH.

CONCLUSIONS AND IMPLICATIONS

PD-L1 is a viable therapeutic target in PH, acting through a signalling axis involving MDSC.

LINKED ARTICLES

This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.1/issuetoc.

Temporal echocardiographic assessment of pulmonary hypertension in idiopathic pulmonary fibrosis patients treated with nintedanib with or without oxygen therapy

Background

Nintedanib is an inhibitor of receptor tyrosine kinases, including vascular endothelial growth factor receptor, but its effects on pulmonary hypertension (PH) in idiopathic pulmonary fibrosis (IPF) patients with chronic hypoxia were unclear.

Methods

This study included a nintedanib prospective study and historical control study. In the nintedanib prospective study, pulmonary artery systolic pressure (PASP) measured using transthoracic echocardiography was evaluated at six points during 48 weeks in 16 IPF patients in whom nintedanib was started. In the historical control study, adjusted annual change in PASP was compared between patients treated with (n = 16) and without (n = 15) nintedanib.

Results

In the nintedanib prospective study, the mean PASP at 48 weeks after starting nintedanib was significantly higher compared to that at baseline. When IPF patients were divided into two groups, IPF patients with or without long-term oxygen treatment (LTOT), mean PASP at 48 weeks was significantly higher than that at baseline only in IPF patients receiving LTOT (P = 0.001). In the historical control study, adjusted annual change in PASP in IPF patients treated with nintedanib was significantly lower than that in patients treated with no antifibrotic agents when considering patients without LTOT (0.26 mmHg vs 7.05 mmHg; P = 0.011).

Conclusions

We found differential effects of nintedanib on PH between IPF patients with or without LTOT. Nintedanib may have a disadvantageous effect on PH in IPF patients with LTOT. Conversely, nintedanib treatment may be beneficial to PH in IPF patients without LTOT.

Electronic supplementary material

The online version of this article (10.1186/s12890-019-0918-3) contains supplementary material, which is available to authorized users.