Is cardiac tissue more susceptible than lung to oxidative effects induced by chronic nasotropic instillation of residual oil fly ash (ROFA)?

The current study aimed to determine the role of oxidants in cardiac and pulmonary toxicities induced by chronic exposure to ROFA. Eighty Wistar rats were divided into four groups: G1 (10 mu L Saline), G2 (ROFA 50 mu g/10 mu L), G3 (ROFA 250 mu g/10 mu L) and G4 (ROFA 500 mu g/10 mu L). Rats received ROFA by nasotropic instillation for 90 days. After that, they were euthanized and bronchoalveolar lavage (BAL) was performed for total count of leukocytes, protein and lactate dehydrogenase (LDH) determinations. Lungs and heart were removed to measure lipid peroxidation (MDA), catalase (CAT) and superoxide dismutase (SOD) activity. BAL presented an increase in leukocytes count in G4 in comparison to the Saline group (p = 0.019). In lung, MDA level was not modified by ROFA, while CAT was higher in G4 when compared to all other groups (p = 0.013). In heart, G4 presented an increase in MDA (p = 0.016) and CAT (p = 0.027) levels in comparison to G1. The present study demonstrated cardiopulmonary oxidative changes after a chronic ROFA exposure. More specifically, the heart tissue seems to be more susceptible to oxidative effects of long-term exposure to ROFA than the lung.

Modelo experimental de perfusão pulmonar ex vivo em ratos: avaliação histopatológica e de apoptose celular em pulmões preservados com solução de baixo potássio dextrana vs. solução histidina-triptofano-cetoglutarato

OBJETIVO: Comparar os achados histopatológicos e de apoptose em pulmões de ratos preservados em soluções low-potassium dextran (LPD, baixo potássio dextrana), histidine-tryptophan-ketoglutarate (HTK, histidina-triptofano-cetoglutarato) ou salina normal (SN) em 6 h e 12 h de isquemia pela utilização de um modelo experimental de perfusão pulmonar ex vivo. MÉTODOS: Sessenta ratos Wistar foram anestesiados, randomizados e submetidos à perfusão anterógrada pela artéria pulmonar com uma das soluções preservadoras. Após a extração, os blocos cardiopulmonares foram preservados por 6 ou 12 h a 4ºC, sendo então reperfundidos com sangue homólogo em um sistema de perfusão ex vivo durante 60 min. Ao final da reperfusão, fragmentos do lobo médio foram extraídos e processados para histopatologia, sendo avaliados os seguintes parâmetros: congestão, edema alveolar, hemorragia alveolar, hemorragia, infiltrado inflamatório e infiltrado intersticial. O grau de apoptose foi avaliado pelo método TdT-mediated dUTP nick end labeling. RESULTADOS: A histopatologia demonstrou que todos os pulmões preservados com SN apresentaram edema alveolar após 12 h de isquemia. Não houve diferenças em relação ao grau de apoptose nos grupos estudados. CONCLUSÕES: No presente estudo, os achados histopatológicos e de apoptose foram semelhantes com o uso das soluções LPD e HTK, enquanto a presença de edema foi significativamente maior com o uso de SN.

Molecular Analysis of the Differentiation Potential of Murine Mesenchymal Stem Cells from Tissues of Endodermal or Mesodermal Origin

Mesenchymal stem cells (MSCs) have received great attention due to their remarkable regenerative, angiogenic, antiapoptotic, and immunosuppressive properties. Although conventionally isolated from the bone marrow, they are known to exist in all tissues and organs, raising the question on whether they are identical cell populations or have important differences at the molecular level. To better understand the relationship between MSCs residing in different tissues, we analyzed the expression of genes related to pluripotency (SOX2 and OCT-4) and to adipogenic (C/EBP and ADIPOR1), osteogenic (OMD and ALP), and chondrogenic (COL10A1 and TRPV4) differentiation in cultures derived from murine endodermal (lung) and mesodermal (adipose) tissue maintained in different conditions. MSCs were isolated from lungs (L-MSCs) and inguinal adipose tissue (A-MSCs) and cultured in normal conditions, in overconfluence or in inductive medium for osteogenic, adipogenic, or chondrogenic differentiation. Cultures were characterized for morphology, immunophenotype, and by quantitative real-time reverse transcription-polymerase chain reaction for expression of pluripotency genes or markers of differentiation. Bone marrow-derived MSCs were also analyzed for comparison of these parameters. L-MSCs and A-MSCs exhibited the typical morphology, immunophenotype, and proliferation and differentiation pattern of MSCs. The analysis of gene expression showed a higher potential of adipose tissue-derived MSCs toward the osteogenic pathway and of lung-derived MSCs to chondrogenic differentiation, representing an important contribution for the definition of the type of cell to be used in clinical trials of cell therapy and tissue engineering.

The effects on mucociliary clearance of prednisone associated with bronchial section

OBJECTIVE: Infections have been and remain the major cause of morbidity and mortality after lung transplantation. Because mucociliary clearance plays an important role in human defense mechanisms, the influence of drugs on the mucociliary epithelium of patients undergoing lung transplantation must be examined. Prednisone is the most important corticosteroid used after lung transplantation. The aim of this study was to evaluate the effects of bronchial transection and prednisone therapy on mucociliary clearance. METHODS: A total of 120 rats were assigned to 4 groups according to surgical procedure or drug therapy: prednisone therapy (1.25 mg/kg/day); bronchial section and anastomosis + prednisone therapy (1.25 mg/kg/day); bronchial section + saline solution (2 ml/day); and saline solution (2 ml/day). After 7, 15, or 30 days, the animals were sacrificed, and the lungs were removed from the thoracic cavity. The in situ mucociliary transport velocity, ciliary beat frequency and in vitro mucus transportability were evaluated. RESULTS: Animals undergoing bronchial section surgery and anastomosis had a significant decrease in the ciliary beat frequency and mucociliary transport velocity 7 and 15 days after surgery (p<0.001). These parameters were normalized 30 days after the surgical procedure. Prednisone improved mucous transportability in the animals undergoing bronchial section and anastomosis at 15 and 30 days (p<0.05). CONCLUSION: Bronchial section and anastomosis decrease mucociliary clearance in the early postoperative period. Prednisone therapy improves mucus transportability in animals undergoing bronchial section and anastomosis.

Equid herpesvirus type-1 exhibits neurotropism and neurovirulence in a mouse model

Intranasal inoculation of equid herpesvirus type-1 (EHV-1) Brazilian strains A4/72 and A9/92 induced an acute and lethal infection in four different inbred mouse strains. Clinical and neurological signs appeared between the 2nd and 3rd day post inoculation (dpi) and included weight loss, ruffled fur, a hunched posture, crouching in corners, nasal and ocular discharges, dyspnoea, dehydration and increased salivation. These signs were followed by increased reactivity to external stimulation, seizures, recumbency and death. The virus was recovered consistently from the brain and viscera of all mice with neurological signs. Histopathological changes consisted of leptomeningitis, focal haemorrhage, ventriculitis, neuronal degeneration and necrosis, neuronophagia, non-suppurative inflammation, multifocal gliosis and perivascular infiltration of polymorphonuclear and mononuclear cells. Immunohistochemical examination demonstrated that EHV-1 strains A4/72 and A9/92 replicated in neurons of the olfactory bulb, the cortex and the hippocampus. In contrast, mice inoculated with the EHV-1 Brazilian strain A3/97 showed neither weight loss nor apparent clinical or neurological signs; however, the virus was recovered consistently from their lungs at 3 dpi. These three EHV-1 strains showed distinct degrees of virulence and tissue tropism in mice. EHV-1 strains A4/72 and A9/92 exhibited a high degree of central nervous system tropism with neuroinvasion and neurovirulence. EHV-1 strain A3/97 was not neurovirulent despite being detected in the brains of infected BALB/c nude mice. These findings indicate that several inbred mouse strains are susceptible to neuropathogenic EHV-1 strains and should be useful models for studying the pathogenesis and mechanisms contributing to EHV-induced myeloencephalopathy in horses. (C) 2011 Elsevier Ltd. All rights reserved.

Phoneutria nigriventer spider toxin Tx2-6 causes priapism and death: A histopathological investigation in mice

Phoneutria nigriventer spider bite causes priapism, an effect attributed to the peptide toxins Tx2-5 and Tx2-6 and involving nitric oxide. Tx2-6 (MW = 5287) is known to delay the inactivation of Sodium channels in the same fashion as many other venom toxins. In the present study we evaluated the i.p. dose that induces priapism and the other symptoms in mice. Animals killed by the toxin or crude venom (0.85 mg/kg) were autopsied and a pathological study of brain, lung, kidney, liver and heart was undertaken using standard techniques. The same protocol was employed with animals injected with crude venom. Results showed that priapism is the first sign of intoxication, followed by piloerection, abundant salivation and tremors. An i.p. injection of about 0.3 mu g/kg induced only priapism with minimal side-effects. The most remarkable histological finding was a general vascular congestion in all organs studied. Penis showed no necrosis or damage. Lungs showed vascular congestion and alveolar hemorrhage. Heart showed also sub-endothelial hemorrhage. Brain showed only a mild edema and vascular congestion. Results obtained with crude venom closely resemble those of purified toxin. We conclude that Tx2-6 have profound effects on the vascular bed especially in lungs and heart, which may be the cause of death. Interestingly brain tissue was less affected and the observed edema may be attributed to respiratory impairment. To the best of our knowledge this is the first histopathological investigation on this toxin and venom suggesting a possible cause of death. (C) 2012 Elsevier Ltd. All rights reserved.

How large is the lung recruitability in early acute respiratory distress syndrome: a prospective case series of patients monitored by computed tomography

Introduction: The benefits of higher positive end expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) have been modest, but few studies have fully tested the "open-lung hypothesis". This hypothesis states that most of the collapsed lung tissue observed in ARDS can be reversed at an acceptable clinical cost, potentially resulting in better lung protection, but requiring more intensive maneuvers. The short-/middle-term efficacy of a maximum recruitment strategy (MRS) was recently described in a small physiological study. The present study extends those results, describing a case-series of non-selected patients with early, severe ARDS submitted to MRS and followed until hospital discharge or death. Methods: MRS guided by thoracic computed tomography (CT) included two parts: a recruitment phase to calculate opening pressures (incremental steps under pressure-controlled ventilation up to maximum inspiratory pressures of 60 cmH(2)O, at constant driving-pressures of 15 cmH(2)O); and a PEEP titration phase (decremental PEEP steps from 25 to 10 cmH2O) used to estimate the minimum PEEP to keep lungs open. During all steps, we calculated the size of the non-aerated (-100 to +100 HU) compartment and the recruitability of the lungs (the percent mass of collapsed tissue re-aerated from baseline to maximum PEEP). Results: A total of 51 severe ARDS patients, with a mean age of 50.7 years (84% primary ARDS) was studied. The opening plateau-pressure was 59.6 (+/- 5.9 cmH(2)O), and the mean PEEP titrated after MRS was 24.6 (+/- 2.9 cmH(2)O). Mean PaO2/FiO(2) ratio increased from 125 (+/- 43) to 300 (+/- 103; P < 0.0001) after MRS and was sustained above 300 throughout seven days. Non-aerated parenchyma decreased significantly from 53.6% (interquartile range (IQR): 42.5 to 62.4) to 12.7% (IQR: 4.9 to 24.2) (P < 0.0001) after MRS. The potentially recruitable lung was estimated at 45% (IQR: 25 to 53). We did not observe major barotrauma or significant clinical complications associated with the maneuver. Conclusions: MRS could efficiently reverse hypoxemia and most of the collapsed lung tissue during the course of ARDS, compatible with a high lung recruitability in non-selected patients with early, severe ARDS. This strategy should be tested in a prospective randomized clinical trial.

Comparative analysis of the pathological events involved in immune and non-immune TRALI models

Background and Objectives Transfusion-related acute lung injury (TRALI) is characterized by leukocyte transmigration and alveolar capillary leakage shortly after transfusion. TRALI pathogenesis has not been fully elucidated. In some cases, the infusion of alloantibodies (immune model), whereas in others the combination of neutrophil priming by proinflammatory molecules with the subsequent infusion of biological response modifiers (BRMs) in the hemocomponent (non-immune model) have been implicated. Our aim was to compare the pathological events involved in TRALI induced by antibodies or BRMs using murine models. Materials and Methods In the immune model, human HNA-2+ neutrophils were incubated in vitro with a monoclonal antibody (anti-CD177, clone 7D8) directed against the HNA-2 antigen and injected i.v. in NOD/SCID mice. In the non-immune model, BALB/c mice were treated with low doses of lipopolysaccharide (LPS) followed by platelet-activating factor (PAF) infusion 2 h later. Forty minutes after PAF administration, or 6 h after neutrophil injection, lungs were isolated and histological analysis, determination of a variety of cytokines and chemokines including keratinocyte-derived chemokine (KC), MIP-2, the interleukins IL-1 beta, IL-6, IL-8 as well as TNFa, cell influx and alveolar capillary leakage were performed. Results In both models, characteristic histological findings of TRALI and an increase in KC and MIP-2 levels were detected. In contrast to the immune model, in the non-immune model, there was a dramatic increase in IL-1 beta and TNFa. However, capillary leakage was only detected if PAF was administrated. Conclusions Regardless of the triggering event(s), KC, MIP-2 and integrins participate in TRALI pathogenesis, whereas PAF is essential for capillary leakage when two events are involved.

Angiotensin II type 1 receptor blockade partially attenuates hypoxia-induced pulmonary hypertension in newborn piglets: relationship with the nitrergic system

The objective of this study was to observe possible interactions between the renin-angiotensin and nitrergic systems in chronic hypoxia-induced pulmonary hypertension in newborn piglets. Thirteen chronically instrumented newborn piglets (6.3 +/- 0.9 days; 2369 +/- 491 g) were randomly assigned to receive saline (placebo, P) or the AT(1) receptor (AT(1)-R) blocker L-158,809 (L) during 6 days of hypoxia (FiO(2) = 0.12). During hypoxia, pulmonary arterial pressure (Ppa; P < 0.0001), pulmonary vascular resistance (PVR; P < 0.02) and the pulmonary to systemic vascular resistance ratio (PVR/SVR; P < 0.05) were significantly attenuated in the L (N = 7) group compared to the P group (N = 6). Western blot analysis of lung proteins showed a significant decrease of endothelial NOS (eNOS) in both P and L animals, and of AT(1)-R in P animals during hypoxia compared to normoxic animals (C group, N = 5; P < 0.01 for all groups). AT(1)-R tended to decrease in L animals. Inducible NOS (iNOS) did not differ among P, L, and C animals and iNOS immunohistochemical staining in macrophages was significantly more intense in L than in P animals (P < 0.01). The vascular endothelium showed moderate or strong eNOS and AT(1)-R staining. Macrophages and pneumocytes showed moderate or strong iNOS and AT(1)-R staining, but C animals showed weak iNOS and AT(1)-R staining. Macrophages of L and P animals showed moderate and weak AT(2)-R staining, respectively, but the endothelium of all groups only showed weak staining. In conclusion, pulmonary hypertension induced by chronic hypoxia in newborn piglets is partially attenuated by AT(1)-R blockade. We suggest that AT(1)-R blockade might act through AT(2)-R and/or Mas receptors and the nitrergic system in the lungs of hypoxemic newborn piglets.

Rho-kinase inhibition attenuates airway responsiveness, inflammation, matrix remodeling, and oxidative stress activation induced by chronic inflammation

Possa SS, Charafeddine HT, Righetti RF, da Silva PA, Almeida-Reis R, Saraiva-Romanholo BM, Perini A, Prado CM, Leick-Maldonado EA, Martins MA, Tiberio ID. Rho-kinase inhibition attenuates airway responsiveness, inflammation, matrix remodeling, and oxidative stress activation induced by chronic inflammation. Am J Physiol Lung Cell Mol Physiol 303: L939-L952, 2012. First published September 21, 2012; doi:10.1152/ajplung.00034.2012.-Several studies have demonstrated the importance of Rho-kinase in the modulation of smooth muscle contraction, airway hyperresponsiveness, and inflammation. However, the effects of repeated treatment with a specific inhibitor of this pathway have not been previously investigated. We evaluated the effects of repeated treatment with Y-27632, a highly selective Rho-kinase inhibitor, on airway hyperresponsiveness, oxidative stress activation, extracellular matrix remodeling, eosinophilic inflammation, and cytokine expression in an animal model of chronic airway inflammation. Guinea pigs were subjected to seven ovalbumin or saline exposures. The treatment with Y-27632 (1 mM) started at the fifth inhalation. Seventy-two hours after the seventh inhalation, the animals' pulmonary mechanics were evaluated, and exhaled nitric oxide (E-NO) was collected. The lungs were removed, and histological analysis was performed using morphometry. Treatment with Y-27632 in sensitized animals reduced E-NO concentrations, maximal responses of resistance, elastance of the respiratory system, eosinophil counts, collagen and elastic fiber contents, the numbers of cells positive for IL-2, IL-4, IL-5, IL-13, inducible nitric oxide synthase, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, transforming growth factor-beta, NF-kappa B, IFN-gamma, and 8-iso-prostaglandin F2 alpha contents compared with the untreated group (P < 0.05). We observed positive correlations among the functional responses and inflammation, remodeling, and oxidative stress pathway activation markers evaluated. In conclusion, Rho-kinase pathway activation contributes to the potentiation of the hyperresponsiveness, inflammation, the extracellular matrix remodeling process, and oxidative stress activation. These results suggest that Rho-kinase inhibitors represent potential pharmacological tools for the control of asthma.

Isolation and characterization of moojenin, an acid-active, anticoagulant metalloproteinase from Bothrops moojeni venom

A fibrinogenolytic metalloproteinase from Bothrops moojeni venom, named moojenin, was purified by a combination of ion-exchange chromatography on DEAE-Sephacel and gel filtration on Sephacryl S-300. SDS-PAGE analysis indicated that moojenin consists of a single polypeptide chain and has a molecular mass about 45 kDa. Sequencing of moojenin by Edman degradation revealed the amino acid sequence LGPDIVSPPVCGNELLEV-GEECDCGTPENCQNE, which showed strong identity with many other snake venom metalloproteinases (SVMPs). The enzyme cleaves the A alpha-chain of fibrinogen first, followed by the E beta-chain, and shows no effects on the gamma-chain. Moojenin showed a coagulant activity on bovine plasma about 3.1 fold lower than crude venom. The fibrinogenolytic and coagulant activities of the moojenin were abolished by preincubation with EDTA, 1,10-phenanthroline and beta-mercaptoethanol. Moojenin showed maximum activity at temperatures ranging from 30 to 40 degrees C and its optimal pH was 4.0. Its activity was completely lost at temperatures above 50 degrees C. Moojenin induced necrosis in liver and muscle, evidenced by morphological alterations, but did not cause histological alterations in mouse lungs, kidney or heart. Moojenin rendered the blood uncoagulatable when it was intraperitoneally administered into mice. This metalloproteinase may be of medical interest because of its anticoagulant activity. (C) 2012 Elsevier Ltd. All rights reserved.

Exercise Inhibits Allergic Lung Inflammation

Aerobic conditioning (AC) performed either during or after sensitization reduces allergic inflammation in mice; however, the effects of AC performed before and during allergic sensitization on airway inflammation are unknown. Mice were divided into Control, AC, OVA, and AC + OVA groups. Mice were trained in a treadmill followed by either ovalbumin (OVA) sensitization or saline administration. Peribronchial inflammation, OVA-specific IgE and IgG1 titers, the expression of Th1 and Th2 cytokines, and airway remodeling were evaluated, as well as the expression of Eotaxin, RANTES, ICAM-1, VCAM-1, TGF-beta and VEGF. Aerobic conditioning performed before and during allergic sensitization displayed an inhibitory effect on the OVA-induced migration of eosinophils and lymphocytes to the airways, a reduction of IgE and IgG1 titers and an inhibition of the expression of Th2 cytokines. The AC + OVA group also demonstrated reduced expression of ICAM-1, VCAM-1, RANTES, TGF-beta and VEGF, as well as decreased airway remodeling (p < 0.05). The effects of AC before and during the sensitization process inhibit allergic airway inflammation and reduce the production of Th2 cytokines and allergen-specific IgE and IgG1.

Immunophenotyping and extracellular matrix remodeling in pulmonary and extrapulmonary sarcoidosis

Objective: To investigate the significance of cellular immune markers, as well as that of collagen and elastic components of the extracellular matrix, within granulomatous structures in biopsies of patients with pulmonary or extrapulmonary sarcoidosis. Methods: We carried out qualitative and quantitative evaluations of inflammatory cells, collagen fibers, and elastic fibers in granulomatous structures in surgical biopsies of 40 patients with pulmonary and extrapulmonary sarcoidosis using histomorphometry, immunohistochemistry, picrosirius red staining, and Weigert's resorcin-fuchsin staining. Results: The extrapulmonary tissue biopsies presented significantly higher densities of lymphocytes, macrophages, and neutrophils than did the lung tissue biopsies. Pulmonary granulomas showed a significantly higher number of collagen fibers and a lower density of elastic fibers than did extrapulmonary granulomas. The amount of macrophages in the lung samples correlated with FVC (p < 0.05), whereas the amount of CD3+, CD4+, and CD8+ lymphocytes correlated with the FEV1/FVC ratio and VC. There were inverse correlations between TLC and the CD1a+ cell count (p < 0.05), as well as between DLCO and collagen/elastic fiber density (r = -0.90; p = 0.04). Conclusions: Immunophenotyping and remodeling both showed differences between pulmonary and extrapulmonary sarcoidosis in terms of the characteristics of the biopsy samples. These differences correlated with the clinical and spirometric data obtained for the patients, suggesting that two different pathways are involved in the mechanism of antigen clearance, which was more effective in the lungs and lymph nodes.

Morfologia e topografia do fígado e pâncreas de emas Rhea americana

As emas são aves ratitas nativas do continente sul americano, são consideradas aves primitivas do ponto de vista filogenético que constituem um grupo altamente especializado. Este estudo buscou caracterizar macro e microscopicamente o fígado e pâncreas de emas. O material foi coletado no Centro de Multiplicação de Animais Silvestres (CEMAS), na cidade de Mossoró-RN, Brasil, (Registro IBAMA n° 14.78912). Utilizaram-se 20 animais jovens com idade entre dois e seis meses independente do sexo. Em emas, o fígado se relacionava cranialmente com o ápice do coração, dorsalmente com os pulmões, esôfago e o proventrículo gástrico, caudalmente, com o ventrículo gástrico, o baço, o duodeno e parte do jejuno. Apresentava coloração vermelha escura e possuía apenas dois lobos, sendo o direito ligeiramente menor que o esquerdo. Histologicamente, era revestido por uma cápsula de tecido conjuntivo delgada e cada lóbulo hepático pôde ser identificado pela presença evidente de veias centrais, com muitos sinusoides comunicando-se com elas. O pâncreas, ventralmente, apresentava-se como uma fita fina, formado por um lobo dorsal e um lobo ventral. Longitudinalmente o pâncreas em emas localiza-se no mesentério dorsal desde o fígado até a flexura cranial do duodeno, mantendo-se preso às alças duodenais por ligamentos. Histologicamente, era composto por uma cápsula delgada de tecido conjuntivo denso, com discretos lóbulos separados por tecido conjuntivo capsular, compostos por estruturas tubuloalveolares e ductos. O fígado e pâncreas de emas apresentam padrão morfológico similar ao descrito para aves domésticas.

Vascular dysfunction by myofibroblast activation in patients with idiopathic pulmonary fibrosis and prognostic significance

In this study, we demonstrated the importance of telomerase protein expression and determined the relationships among telomerase, endothelin-1 (ET-1) and myofibroblasts during early and late remodeling of parenchymal and vascular areas in usual interstitial pneumonia (UIP) using 27 surgical lung biopsies from patients with idiopathic pulmonary fibrosis (IPF). Telomerase+, myofibroblasts alpha-SMA+, smooth muscle cells caldesmon+, endothelium ET-1+ cellularity, and fibrosis severity were evaluated in 30 fields covering normal lung parenchyma, minimal fibrosis (fibroblastic foci), severe ( mural) fibrosis, and vascular areas of UIP by the point-counting technique and a semiquantitative score. The impact of these markers was determined in pulmonary functional tests and follow-up until death from IPF. Telomerase and ET-1 expression was significantly increased in normal and vascular areas compared to areas of fibroblast foci. Telomerase and ET-1 expression was inversely correlated with minimal fibrosis in areas of fibroblast foci and directly associated with severe fibrosis in vascular areas. Telomerase activity in minimal fibrosis areas was directly associated with diffusing capacity of the lung for oxygen/alveolar volume and ET-1 expression and indirectly associated with diffusing capacity of the lungs for carbon monoxide and severe fibrosis in vascular areas. Cox proportional hazards regression revealed a low risk of death for females with minimal fibrosis displaying high telomerase and ET-1 expression in normal areas. Vascular dysfunction by telomerase/ET-1 expression was found earlier than vascular remodeling by myofibroblast activation in UIP with impact on IPF evolution, suggesting that strategies aimed at preventing the effect of these mediators may have a greater impact on patient outcome.