Idiopathic pulmonary fibrosis (IPF) is a chronic age-related lung disease with high mortality that is characterized by abnormal scarring of the lung parenchyma. There has been a recent attempt to ...define the age-associated changes predisposing individuals to develop IPF. Age-related perturbations that are increasingly found in epithelial cells and fibroblasts from IPF lungs compared with age-matched cells from normal lungs include defective autophagy, telomere attrition, altered proteostasis, and cell senescence. These divergent processes seem to converge in mitochondrial dysfunction and metabolic distress, which potentiate maladaptation to stress and susceptibility to age-related diseases such as IPF. Therapeutic approaches that target aging processes may be beneficial for halting the progression of disease and improving quality of life in IPF patients.
Idiopathic pulmonary fibrosis (IPF) is a fatal age-associated disease that is characterized by progressive and irreversible scarring of the lung. The pathogenesis of IPF is not completely understood ...and current therapies are limited to those that reduce the rate of functional decline in patients with mild-to-moderate disease. In this context, new therapeutic approaches that substantially improve the survival time and quality of life of these patients are urgently needed. Our incomplete understanding of the pathogenic mechanisms of IPF and the lack of appropriate experimental models that reproduce the key characteristics of the human disease are major challenges. As ageing is a major risk factor for IPF, age-related cell perturbations such as telomere attrition, senescence, epigenetic drift, stem cell exhaustion, loss of proteostasis and mitochondrial dysfunction are becoming targets of interest for IPF therapy. In this Review, we discuss current and emerging therapies for IPF, particularly those targeting age-related mechanisms, and discuss future therapeutic approaches.
Myofibroblasts are key effector cells in the extracellular matrix remodelling of systemic sclerosis-associated interstitial lung disease (SSc-ILD); however, the diversity of fibroblast populations ...present in the healthy and SSc-ILD lung is unknown and has prevented the specific study of the myofibroblast transcriptome. We sought to identify and define the transcriptomes of myofibroblasts and other mesenchymal cell populations in human healthy and SSc-ILD lungs to understand how alterations in fibroblast phenotypes lead to SSc-ILD fibrosis.
We performed droplet-based, single-cell RNA-sequencing with integrated canonical correlation analysis of 13 explanted lung tissue specimens (56 196 cells) from four healthy control and four patients with SSc-ILD, with findings confirmed by cellular indexing of transcriptomes and epitopes by sequencing in additional samples.
Examination of gene expression in mesenchymal cells identified two major, SPINT2
and MFAP5
, and one minor, WIF1
, fibroblast populations in the healthy control lung. Combined analysis of control and SSc-ILD mesenchymal cells identified SPINT2
, MFAP5
, few WIF1
fibroblasts and a new large myofibroblast population with evidence of actively proliferating myofibroblasts. We compared differential gene expression between all SSc-ILD and control mesenchymal cell populations, as well as among the fibroblast subpopulations, showing that myofibroblasts undergo the greatest phenotypic changes in SSc-ILD and strongly upregulate expression of collagens and other profibrotic genes.
Our results demonstrate previously unrecognised fibroblast heterogeneity in SSc-ILD and healthy lungs, and define multimodal transcriptome-phenotypes associated with these populations. Our data indicate that myofibroblast differentiation and proliferation are key pathological mechanisms driving fibrosis in SSc-ILD.
ABSTRACT
Mesenchymal stem cells (MSCs) are a populace of non‐haematopoietic multipotent stromal cells, which have the ability to differentiate into tissue derived from a single germ layer. MSCs have ...been isolated from various sites, including adipose tissue, skeletal muscle, synovium, spleen, thymus, lung and amniotic fluid, but are most often isolated from bone marrow. MSCs have several valuable functions that make them a promising therapeutic option in the field of regenerative medicine, including the secretion of anti‐inflammatory cytokines and growth factors, the migration of cells to the site of injury when administered and the ability to ‘rescue’ cells through the transfer of functional mitochondria. They also offer the possibility of autologous cell transplantation, circumventing immune rejection. These properties, among others, make MSCs a promising potential therapeutic agent in the treatment of chronic lung diseases with high rates of morbidity and mortality, such as idiopathic pulmonary fibrosis (IPF), COPD and obstructive bronchiolitis (OB). Numerous animal models have shown the protective and reparative effects of MSCs in models of experimental lung injury. There are currently several clinical trials underway to evaluate the safety and efficacy of MSCs in the treatment of IPF, COPD and OB. While early results are encouraging, a considerable amount of research must be done concerning the safety MSCs, as well as their optimal dosage, time and route of administration. In addition, much is still unknown about the pathogenesis of these chronic lung diseases, as well as the mechanisms MSCs utilize to assist in their repair.
Aging is a natural process characterized by progressive functional impairment and reduced capacity to respond appropriately to environmental stimuli and injury. The incidence of two common chronic ...respiratory diseases (chronic obstructive pulmonary disease COPD and idiopathic pulmonary fibrosis IPF) increases with advanced age. It is plausible, therefore, that abnormal regulation of the mechanisms of normal aging may contribute to the pathobiology of both COPD and IPF. This review discusses the available evidence supporting a number of aging mechanisms, including oxidative stress, telomere length regulation, cellular and immunosenescence, as well as changes in a number of antiaging molecules and the extracellular matrix, which are abnormal in COPD and/or IPF. A better understanding of these abnormalities may help in the design of novel and better therapeutic interventions for these patients.
A comprehensive understanding of the changes in gene expression in cell types involved in idiopathic pulmonary fibrosis (IPF) will shed light on the mechanisms underlying the loss of alveolar ...epithelial cells and development of honeycomb cysts and fibroblastic foci. We sought to understand changes in IPF lung cell transcriptomes and gain insight into innate immune aspects of pathogenesis.We investigated IPF pathogenesis using single-cell RNA-sequencing of fresh lung explants, comparing human IPF fibrotic lower lobes reflecting late disease, upper lobes reflecting early disease and normal lungs.IPF lower lobes showed increased fibroblasts, and basal, ciliated, goblet and club cells, but decreased alveolar epithelial cells, and marked alterations in inflammatory cells. We found three discrete macrophage subpopulations in normal and fibrotic lungs, one expressing monocyte markers, one highly expressing
and
(FABP4
), and one highly expressing
and
(SPP1
). SPP1
macrophages in fibrotic lower lobes showed highly upregulated
and
expression. Low-level local proliferation of SPP1
macrophages in normal lungs was strikingly increased in IPF lungs.Co-localisation and causal modelling supported the role for these highly proliferative SPP1
macrophages in activation of IPF myofibroblasts in lung fibrosis. These data suggest that SPP1
macrophages contribute importantly to lung fibrosis in IPF, and that therapeutic strategies targeting MERTK and macrophage proliferation may show promise for treatment of this disease.
Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease of unknown etiology. It is characterized by deposition of extracellular matrix proteins, like collagen and fibronectin in the lung ...interstitium leading to respiratory failure. Our understanding of the pathobiology underlying IPF is still incomplete; however, it is accepted that aging is a major risk factor in the disease while growing evidence suggests that the mitochondria plays an important role in the initiation and progression of pulmonary fibrosis. Mitochondria dysfunction and metabolic reprogramming had been identified in different IPF lung cells (alveolar epithelial cells, fibroblasts, and macrophages) promoting low resilience and increasing susceptibility to activation of profibrotic responses. Here we summarize changes in mitochondrial numbers, biogenesis, turnover and associated metabolic adaptations that promote disrepair and fibrosis in the lung. Finally, we highlight new possible therapeutic approaches focused on ameliorate mitochondrial dysfunction.
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IPF lung fibroblasts have a senescent phenotype Álvarez, Diana; Cárdenes, Nayra; Sellarés, Jacobo ...
American journal of physiology. Lung cellular and molecular physiology,
12/2017, Letnik:
313, Številka:
6
Journal Article
Recenzirano
Odprti dostop
The mechanisms of aging that are involved in the development of idiopathic pulmonary fibrosis (IPF) are still unclear. Although it has been hypothesized that the proliferation and activation of human ...lung fibroblasts (hLFs) are essential in IPF, no studies have assessed how this process works in an aging lung. Our goal was to elucidate if there were age-related changes on primary hLFs isolated from IPF lungs compared with age-matched controls. We investigated several hallmarks of aging in hLFs from IPF patients and age-matched controls. IPF hLFs have increased cellular senescence with higher expression of β-galactosidase, p21, p16, p53, and cytokines related to the senescence-associated secretory phenotype (SASP) as well as decreased proliferation/apoptosis compared with age-matched controls. Additionally, we observed shorter telomeres, mitochondrial dysfunction, and upon transforming growth factor-β stimulation, increased markers of endoplasmic reticulum stress. Our data suggest that IPF hLFs develop senescence resulting in a decreased apoptosis and that the development of SASP may be an important contributor to the fibrotic process observed in IPF. These results might change the existing paradigm, which describes fibroblasts as aberrantly activated cells, to a cell with a senescence phenotype.
Objective: to describe and explore the relationship of loneliness, anxiety and depression with adoption of the caregiver role among individuals caring for people with chronic diseases in Colombia. ...Methods: this was an exploratory and cross-sectional study involving 960 primary caregivers of individuals with chronic diseases. We applied the Caregiver Role Adoption Scale, the University of California at Los Angeles Loneliness Scale, and the Anxiety and Depression Scale. Principal component and multiple correspondence analyses were performed for clustering. Results: among the participating caregivers, 40.8% reported experiencing depression, 59% reported anxiety, 54.6% reported moderate to severe loneliness, and 88.6% reported satisfactory adoption of the caregiver role. Caregivers who presented basic or insufficient role adoption levels tended to have higher scores for anxiety, depression and loneliness. Conclusion: adoption of the caregiver role is a mediator in the anxiety, depression and loneliness levels among caregivers. Strategies aimed at supporting caregivers should include training for the caregiver role to mitigate the negative impacts of anxiety, depression and loneliness.
Objetivo: descrever e explorar a relação entre a solidão, a ansiedade e a depressão com a adoção do papel de cuidador entre os indivíduos que cuidam de pessoas com doenças crônicas na Colômbia. Método: trata-se de um estudo exploratório e transversal que envolveu 960 cuidadores primários de indivíduos com doenças crônicas. Foi aplicada a Escala de Adoção do Papel de Cuidador, a Escala de Solidão da Universidade da Califórnia em Los Angeles e a Escala de Ansiedade e Depressão. Foram realizadas análises de componentes principais e de correspondência múltipla para o agrupamento. Resultados: entre os cuidadores participantes, 40,8% relataram ter depressão, 59% relataram ansiedade, 54,6% relataram solidão moderada a grave e 88,6% relataram uma adoção satisfatória do papel de cuidador. Os cuidadores que apresentaram níveis básicos ou insuficientes de adoção do papel tenderam a ter pontuações mais elevadas de ansiedade, depressão e solidão. Conclusão: a adoção do papel de cuidador é um mediador nos níveis de ansiedade, depressão e solidão entre os cuidadores. As estratégias destinadas a apoiar os cuidadores devem incluir o treinamento para o papel de cuidador, a fim de atenuar os impactos negativos da ansiedade, da depressão e da solidão.
Objetivo: describir y explorar la relación de la soledad, la ansiedad y la depresión con la adopción del rol de cuidador entre personas que se ocupan de cuidar pacientes con enfermedades crónicas en Colombia. Métodos: se trató de un estudio exploratorio y transversal con la participación de 960 cuidadores principales de personas con enfermedades crónicas. Aplicamos la Escala de Adopción del Rol de Cuidador, la Escala de Soledad de la Universidad de California de Los Ángeles y la Escala de Ansiedad y Depresión. Se realizaron análisis de componentes principales y de correspondencia múltiple para el clustering . Resultados: el 40,8% de los cuidadores que participaron en el estudio informó padecer depresión, el 59% informó ansiedad, el 54,6% indicó soledad de moderada a grave y el 88,6% presentó adopción satisfactoria del rol de cuidador. Los cuidadores que presentaron los niveles básico o insuficiente en términos de adopción del rol tendieron a obtener puntuaciones de ansiedad, depresión y soledad más elevadas. Conclusión: adoptar el rol de cuidador es un mediador de los niveles de ansiedad, depresión y soledad entre los cuidadores. Las estrategias dirigidas a apoyar a los cuidadores deberían incluir preparación para dicho rol a fin de mitigar los efectos negativos de la ansiedad, la depresión y la soledad.
Endothelial cells contribute to a subset of cardiac fibroblasts by undergoing endothelial-to-mesenchymal transition, but whether cardiac fibroblasts can adopt an endothelial cell fate and directly ...contribute to neovascularization after cardiac injury is not known. Here, using genetic fate map techniques, we demonstrate that cardiac fibroblasts rapidly adopt an endothelial-cell-like phenotype after acute ischaemic cardiac injury. Fibroblast-derived endothelial cells exhibit anatomical and functional characteristics of native endothelial cells. We show that the transcription factor p53 regulates such a switch in cardiac fibroblast fate. Loss of p53 in cardiac fibroblasts severely decreases the formation of fibroblast-derived endothelial cells, reduces post-infarct vascular density and worsens cardiac function. Conversely, stimulation of the p53 pathway in cardiac fibroblasts augments mesenchymal-to-endothelial transition, enhances vascularity and improves cardiac function. These observations demonstrate that mesenchymal-to-endothelial transition contributes to neovascularization of the injured heart and represents a potential therapeutic target for enhancing cardiac repair.
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