Angiotensinogen gene G-6A polymorphism influences idiopathic pulmonary fibrosisdisease progression

Angiotensin II is a growth factor that plays a key role in the physiopathology of idiopathic pulmonary fibrosis (IPF). A nucleotide substitution of an adenine instead of a guanine (G-6A) in the proximal promoter region of angiotensinogen (AGT), the precursor of angiotensin II, has been associated with an increased gene transcription rate. In order to investigate whether the G-6A polymorphism of the AGT gene is associated with IPF development, severity and progression, the present study utilised a case–control study design and genotyped G-6A in 219 patients with IPF and 224 control subjects. The distribution of G-6A genotypes and alleles did not significantly differ between cases and controls. The G-6A polymorphism of the AGT gene was not associated with disease severity at diagnosis. The presence of the A allele was strongly associated with increased alveolar arterial oxygen tension difference during follow-up, after controlling for the confounding factors. Higher alveolar arterial oxygen tension changes over time were observed in patients with the AA genotype (0.37¡0.7 mmHg (0.049¡0.093 kPa) per month) compared to GA genotype (0.12¡1 mmHg (0.016¡0.133 kPa) per month) and GG genotype (0.2¡0.6 mmHg (0.027¡0.080 kPa) per month). G-6A polymorphism of the angiotensinogen gene is associated with idiopathic pulmonary fibrosis progression but not with disease predisposition. This polymorphism could have a predictive significance in idiopathic pulmonary fibrosis patients.Supported by grants from FIS-PI; FISPI060064, FIS-IDIBAPS CM05/00118, Sociedad Española de Neumologia y Cirugia Torácica (SEPAR)-Fundación Respira and Faculdade Capivari, Spain.Peer reviewe

Lung myofibroblasts are characterized by down-regulated cyclooxygenase-2 and its main metabolite, prostaglandin E2.

Background: Prostaglandin E2 (PGE2), the main metabolite of cyclooxygenase (COX), is a well-known anti-fibrotic agent. Moreover, myofibroblasts expressing a-smooth muscle actin (a-SMA), fibroblast expansion and epithelial-mesenchymal transition (EMT) are critical to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Our aim was to investigate the expression of COX-2 and PGE2 in human lung myofibroblasts and establish whether fibroblast-myofibroblast transition (FMT) and EMT are associated with COX-2 and PGE2 down-regulation. Methods: Fibroblasts obtained from IPF patients (n = 6) and patients undergoing spontaneous pneumothorax (control,n = 6) and alveolar epithelial cell line A549 were incubated with TGF-b1 and FMT and EMT markers were evaluated. COX-2 and a-SMA expression, PGE2 secretion and cell proliferation were measured after IL-1b and PGE2 incubation. Results: Myofibroblasts from both control and IPF fibroblast cultures stimulated with IL-1b showed no COX-2 expression. IPF fibroblasts showed increased myofibroblast population and reduced COX-2 expression in response to IL-1b. TGF-b1 increased the number of myofibroblasts in a time-dependent manner. In contrast, TGF-b1 induced slight COX-2 expression at 4 h (without increase in myofibroblasts) and 24 h, but not at 72 h. Both IPF and control cultures incubated with TGF-b1 for 72 h showed diminished COX-2 induction, PGE2 secretion and a-SMA expression after IL-1b addition. The latter decreased proliferation in fibroblasts but not in myofibroblasts. A549 cells incubated with TGF-b1 for 72 h showed downregulated COX-2 expression and low basal PGE2 secretion in response to IL-1b. Immuno-histochemical analysis of IPF lung tissue showed no COX-2 immuno-reactivity in myofibroblast foci. Conclusions: Myofibroblasts are associated with COX-2 down-regulation and reduced PGE2 production, which could be crucial in IPF development and progression

Telomerase and Telomere Length in Pulmonary Fibrosis

In addition to its expression in stem cells and many cancers,telomerase activity is transiently induced inmurine bleomycin (BLM)induced pulmonary fibrosis with increased levels of telomerase transcriptase (TERT) expression, which is essential for fibrosis. To extend these observations to human chronic fibrotic lung disease,we investigated the expression of telomerase activity in lung fibroblasts from patients with interstitial lung diseases (ILDs), including idiopathic pulmonaryfibrosis (IPF).The resultsshowedthat telomerase activity was induced in more than 66% of IPF lung fibroblast samples, in comparison with less than 29% from control samples,some of which were obtained from lung cancer resections. Less than 4%of the humanIPF lung fibroblast samples exhibited shortened telomeres,whereas less than 6% of peripheral blood leukocyte samples from patients with IPF or hypersensitivity pneumonitis demonstrated shortened telomeres. Moreover, shortened telomeres in lategeneration telomerase RNA component knockout mice did not exert a significant effect on BLM-induced pulmonary fibrosis. In contrast, TERT knockout mice exhibited deficient fibrosis that was independent of telomere length. Finally, TERT expression was up-regulated by a histone deacetylase inhibitor, while the induction of TERT in lung fibroblastswasassociatedwiththebindingofacetylatedhistoneH3K9to the TERT promoter region. These findings indicate that significant telomerase inductionwas evident in fibroblasts from fibroticmurine lungs and a majority of IPF lung samples, whereas telomere shortening was not a common finding in the human blood and lung fibroblast samples. Notably, the animal studies indicated that the pathogenesis of pulmonary fibrosis was independent of telomere length

Peak oxygen uptake during the six-minute walk test in diffuse interstitial lung disease and pulmonary hypertension

Introducción La prueba de marcha de 6 minutos (PM6M) es ampliamente utilizada en la evaluación de la enfermedad pulmonar intersticial difusa (EPID) y en la hipertensión pulmonar (HP). Sin embargo, sus determinantes fisiológicos no han sido bien caracterizados. Objetivo Evaluar los cambios fisiológicos que ocurren durante la PM6M en la EPID y en la HP y compararlos con la prueba de esfuerzo cardiopulmonar (PECP). Material y métodos Se estudiaron 13 pacientes con EPID y 14 con HP mediante PM6M y PECP en cicloergómetro. Durante la PM6M se registraron las variables respiratorias mediante telemetría. Resultados El consumo de oxígeno (VO2), la ventilación y la frecuencia cardiaca mostraron una meseta desde el minuto 3 de la PM6M en ambas patologías. El valor de VO2 no difirió del valor pico en la PECP (14±2 y 15±2ml/kg/min, respectivamente, en la EPID; 16±6 y 16±6ml/kg/min, en la HP). En ambas patologías, disminuyó la saturación arterial de oxígeno, aunque más marcadamente en la EPID (−12±5%, p<0,01). En la HP, el equivalente ventilatorio de CO2 (VE/VCO2) durante la PM6M estaba fuertemente relacionado con la clase funcional (CF) (85±14 en CF III-IV, 44±6 en CF I-II; p<0,001). Conclusiones En la EPID y en la HP la PM6M se comporta como una prueba de esfuerzo máxima, con valores de VO2 similares a la PECP, poniendo de manifiesto limitación de la capacidad de transporte de oxígeno. La monitorización mediante telemetría durante la PM6M puede ser útil para la evaluación clínica de los pacientes con EPID o con HP.Q1Q3Artículo original122-128Introduction The six-minute walk test (6MWT) is widely used in evaluating diffuse interstitial lung disease (ILD) and pulmonary hypertension (PH). However, their physiological determining factors have not been well defined. Objective To evaluate the physiological changes that occur in ILD and PH during the 6MWT, and compare them with the cardiopulmonary exercise test (CPET). Material and methods Thirteen patients with ILD and 14 with PH were studied using the 6MWT and CPET on an ergometer cycle. The respiratory variables were recorded by means of telemetry during the 6MWT. Results Oxygen consumption (VO2), respiratory and heart rate reached a plateau from minute 3 of the 6MWT in both diseases. The VO2 did not differ from the peak value in the CPET (14±2 and 15±2ml/kg/min, respectively, in ILD; 16±6 and 16±6ml/kg/min, in PH). The arterial oxygen saturation decreased in both diseases, although it was more marked in ILD (−12±5%, p<0,01). The ventilatory equivalent for CO2 (VE/VCO2) in PH during the 6MWT was strongly associated with functional class (FC) (85±14 in FC III-IV, 44±6 in FC I-II; p<0,001). Conclusions The 6MWT in ILD and PH behaves like a maximal effort test, with similar VO2 to the CPET, demonstrating a limit in oxygen transport capacity. Monitoring using telemetry during the 6MWT may be useful for the clinical evaluation of patients with ILD or PH

Study of breast cancer incidence in patients of lymphangioleiomyomatosis

The online version of this article (doi:10.1007/s10549-016-3737-8) contains supplementary material, which is available to authorized user

Demographic and clinical profile of idiopathic pulmonary fibrosis patients in Spain: the SEPAR National Registry

BackgroundLittle is known on the characteristics of patients diagnosed with idiopathic pulmonary fibrosis (IPF) in Spain. We aimed to characterize the demographic and clinical profile of IPF patients included in the IPF National Registry of the Spanish Respiratory Society (SEPAR).MethodsThis is a prospective, observational, multicentre and nationwide study that involved 608 IPF patients included in the SEPAR IPF Registry up to June 27th, 2017, and who received any treatment for their disease. IPF patients were predominantly males, ex-smokers, and aged in their 70s, similar to other registries.ResultsUpon inclusion, meanSD predicted forced vital capacity was 77.6%+/- 19.4, diffusing capacity for carbon monoxide was 48.5%+/- 17.7, and the 6-min walk distance was 423.5m +/- 110.4. The diagnosis was mainly established on results from the high-resolution computed tomography in the proper clinical context (55.0% of patients), while 21.2% of patients required invasive procedures (surgical lung biopsy) for definitive diagnosis. Anti-fibrotic treatment was prescribed in 69.4% of cases, 51.5% pirfenidone and 17.9% nintedanib, overall with a good safety profile.Conclusions The SEPAR IPF Registry should help to further characterize current characteristics and future trends of IPF patients in Spain and compare/pool them with other registries and cohorts

Study of breast cancer incidence in patients of lymphangioleiomyomatosis

Molecular evidence has linked the pathophysiology of lymphangioleiomyomatosis (LAM) to that of metastatic breast cancer. Following on this observation, we assessed the association between LAM and subsequent breast cancer. An epidemiological study was carried out using three LAM country cohorts, from Japan, Spain, and the United Kingdom. The number of incident breast cancer cases observed in these cohorts was compared with the number expected on the basis of the country-specific incidence rates for the period 2000–2014. Immunohistochemical studies and exome sequence analysis were performed in two and one tumors, respectively. All cohorts revealed breast cancer standardized incidence ratios (SIRs) ≥ 2.25. The combined analysis of all cases or restricted to pre-menopausal age groups revealed significantly higher incidence of breast cancer: SIR = 2.81, 95 % confidence interval (CI) = 1.32–5.57, P = 0.009; and SIR = 4.88, 95 % CI = 2.29–9.99, P = 0.0007, respectively. Immunohistochemical analyses showed positivity for known markers of lung metastatic potential. This study suggests the existence of increased breast cancer risk among LAM patients. Prospective studies may be warranted to corroborate this result, which may be particularly relevant for pre-menopausal women with LAM. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10549-016-3737-8) contains supplementary material, which is available to authorized users