Decreased Expression of EC-SOD and Fibulin-5 in Alveolar Walls of Lungs From COPD Patients

Introduction: The aim of this study is to analyze the expression of the main oxidant scavenger superoxide dismutase (EC-SOD), its main binding protein Fibulin-5 and several oxidative and nitrosative-derived products in the lung of COPD patients and controls.Materials and methods: Lung tissue samples from 19 COPD patients and 20 control subjects were analyzed. The architecture of elastic fibres was assessed by light and electron microscope histochemical techniques, and levels of EC-SOD and fibulin-5 were analyzed by immunohistochemistry and RT-PCR. The impact of oxidative stress on the extracellular matrix was estimated by immunolocalization of 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) and 3-nitrotyrosine (3-NYT) adducts.Results: Alveolar walls of COPD patients exhibited abnormal accumulations of collapsing elastic fibres, showing a pierced pattern in the amorphous component. The semiquantitative analysis revealed that COPD patients have a significantly reduced expression of both EC-SOD and fibulin-5 (0.59±0.64 and 0.62±0.61, respectively) in alveolar, bronchiolar and arteriolar walls compared to control subjects (1.39±0.63 and 1.55±0.52, respectively, p<0.05). No significant changes in mRNA levels of these proteins were observed between groups. Among the oxidation markers, malondialdehyde was the best in distinguishing COPD patients.Conclusions: COPD patients show a reduced expression of EC-SOD and fibulin-5 in the lung interstitium. Paralleling the reduction of EC-SOD levels, the decrease of fibulin-5 expression in COPD lungs supports the hypothesis of an impaired pulmonary antioxidant response in COPD patients. (AU)

Decreased Expression of EC-SOD and Fibulin-5 in Alveolar Walls of Lungs From COPD Patients.

INTRODUCTION: The aim of this study is to analyze the expression of the main oxidant scavenger superoxide dismutase (EC-SOD), its main binding protein Fibulin-5 and several oxidative and nitrosative-derived products in the lung of COPD patients and controls. MATERIALS AND METHODS: Lung tissue samples from 19 COPD patients and 20 control subjects were analyzed. The architecture of elastic fibres was assessed by light and electron microscope histochemical techniques, and levels of EC-SOD and fibulin-5 were analyzed by immunohistochemistry and RT-PCR. The impact of oxidative stress on the extracellular matrix was estimated by immunolocalization of 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) and 3-nitrotyrosine (3-NYT) adducts. RESULTS: Alveolar walls of COPD patients exhibited abnormal accumulations of collapsing elastic fibres, showing a pierced pattern in the amorphous component. The semiquantitative analysis revealed that COPD patients have a significantly reduced expression of both EC-SOD and fibulin-5 (0.59±0.64 and 0.62±0.61, respectively) in alveolar, bronchiolar and arteriolar walls compared to control subjects (1.39±0.63 and 1.55±0.52, respectively, p<0.05). No significant changes in mRNA levels of these proteins were observed between groups. Among the oxidation markers, malondialdehyde was the best in distinguishing COPD patients. CONCLUSIONS: COPD patients show a reduced expression of EC-SOD and fibulin-5 in the lung interstitium. Paralleling the reduction of EC-SOD levels, the decrease of fibulin-5 expression in COPD lungs supports the hypothesis of an impaired pulmonary antioxidant response in COPD patients.

Decreased Expression of EC-SOD and Fibulin-5 in Alveolar Walls of Lungs From COPD Patients.

INTRODUCTION: The aim of this study is to analyze the expression of the main oxidant scavenger superoxide dismutase (EC-SOD), its main binding protein Fibulin-5 and several oxidative and nitrosative-derived products in the lung of COPD patients and controls. MATERIALS AND METHODS: Lung tissue samples from 19 COPD patients and 20 control subjects were analyzed. The architecture of elastic fibres was assessed by light and electron microscope histochemical techniques, and levels of EC-SOD and fibulin-5 were analyzed by immunohistochemistry and RT-PCR. The impact of oxidative stress on the extracellular matrix was estimated by immunolocalization of 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) and 3-nitrotyrosine (3-NYT) adducts. RESULTS: Alveolar walls of COPD patients exhibited abnormal accumulations of collapsing elastic fibres, showing a pierced pattern in the amorphous component. The semiquantitative analysis revealed that COPD patients have a significantly reduced expression of both EC-SOD and fibulin-5 (0.59±0.64 and 0.62±0.61, respectively) in alveolar, bronchiolar and arteriolar walls compared to control subjects (1.39±0.63 and 1.55±0.52, respectively, p<0.05). No significant changes in mRNA levels of these proteins were observed between groups. Among the oxidation markers, malondialdehyde was the best in distinguishing COPD patients. CONCLUSIONS: COPD patients show a reduced expression of EC-SOD and fibulin-5 in the lung interstitium. Paralleling the reduction of EC-SOD levels, the decrease of fibulin-5 expression in COPD lungs supports the hypothesis of an impaired pulmonary antioxidant response in COPD patients.

PRDM15 Is Associated with Risk of Chronic Obstructive Pulmonary Disease in a Rural Population in Chile.

BACKGROUND: Genome-wide association studies (GWAS) have accelerated our understanding of the genetic underpinnings of chronic obstructive pulmonary disease (COPD); however, GWAS populations have typically consisted of European descent, with ∼1% of Latin American ancestry. OBJECTIVE: To overcome this limitation, we conducted a GWAS in a rural Chilean population with increased COPD risk to investigate genetic variation of COPD risk in this understudied minority population. METHOD: We carried out a case-control study of 214 COPD patients (defined by the GOLD criteria) and 193 healthy controls in Talca, Chile. DNA was extracted from venous blood and genotyped on the Illumina Global Screening Array (n = 754,159 markers). After exclusion based on Hardy-Weinberg equilibrium (p ≤ 0.001), call rates (<95%), and minor allele frequencies (<0.5%) in controls, 455,564 markers were available for logistic regression. RESULTS: PRDM15 rs1054761 C allele (p = 2.22 × 10-7) was associated with decreased COPD risk. Three PRDM15 SNPs located on chromosome 21 were significantly associated with COPD risk (p < 10-6). Two of these SNPs, rs1054761 and rs4075967, were located on a noncoding transcript variant region of the gene. CONCLUSION: PRDM15 overexpression may play a role in the B-cell dysregulation in COPD pathogenesis. To the best of our knowledge, the association between PRDM15 and COPD risk was not previously found in GWAS studies in largely European populations, highlighting the importance of investigating novel variants associated with COPD risk among ethnically diverse populations.

Correction: Deficient pulmonary IFN-ß expression in COPD patients.

[This corrects the article DOI: 10.1371/journal.pone.0217803.].

Deficient pulmonary IFN-ß expression in COPD patients.

COPD patients are prone to acute infectious exacerbations that impair their quality of life and hamper prognosis. The purpose of the present study was to investigate the in situ IFN-ß response in the lungs of stable COPD and non-COPD patients. Lung samples from 70 subjects (9 control never smokers, 19 control smokers without COPD, 21 patients with moderate COPD and 21 patients with very severe COPD) were studied for the expression of IFN-ß, its main transcription factor, IRF-7, and two products of its autocrine function, namely RIG-I and MDA-5, by immunohistochemical techniques and quantitative real-time PCR. IFN-ß, IRF-7, RIG-I and MDA-5 were widely detected in most lung cell types. In epithelial tissues and alveolar macrophages, IFN-ß and IRF-7 labeling scores were decreased up to 65% and 74%, respectively, for COPD patients, paralleling an analogous reduction (43% and 65%, respectively) in the amount of their lung mRNA. Moreover, this decreased production of IFN-ß in COPD patients correlated with a similar decrease in the expression of RIG-I and MDA-5, two essential members of the innate immune system. Our study indicates that most lung cells from stable COPD patients show a constitutive decreased expression of IFN-ß, IRF-7, RIG-I and MDA-5, suggesting that this deficiency is the main cause of their acute viral exacerbations.

[Cellular effectors of the inflammatory response in chronic obstructive pulmonary disease (COPD)]. / Efectores celulares de la respuesta inflamatoria en la enfermedad pulmonar obstructiva crónica.

Approximately 3 million people in the world die every year as a consequence of COPD, which is associated with an abnormal inflammatory response of the lung to noxious particles and gases. This inflammatory pattern causes pathological changes leading to a narrowing of small airways and destruction of lung parenchyma, also known as emphysema. Classically, these changes were associated to macrophages and neutrophils, although T CD8+ lymphocytes were latter added to the equation to explain the origin of emphysematous lesions. However, in recent years, multiple evidences have arisen indicating that inflammatory response in COPD is much more complex. These findings point to a key role for mast cells, dendritic cells, T CD4+ and B cells. The aim of this article is to review such evidence and report what is known so far about those cells involved in the inflammatory response in COPD.

Efectores celulares de la respuesta inflamatoria en la enfermedad pulmonar obstructiva crónica / Cellular effectors of the inflammatory response in chronic obstructive pulmonary disease (COPD)

Approximately 3 million people in the world die every year as a consequence of COPD, which is associated with an abnormal inflammatory response of the lung to noxious particles and gases. This inflammatory pattern causes pathological changes leading to a narrowing of small airways and destruction of lung parenchyma, also known as emphysema. Classically, these changes were associated to macrophages and neutrophils, although T CD8+ lymphocytes were latter added to the equation to explain the origin of emphysematous lesions. However, in recent years, multiple evidences have arisen indicating that inflammatory response in COPD is much more complex. These findings point to a key role for mast cells, dendritic cells, T CD4+ and B cells. The aim of this article is to review such evidence and report what is known so far about those cells involved in the inflammatory response in COPD.

Ecto-nucleotidases activities in the contents of ovarian endometriomas: potential biomarkers of endometriosis.

Endometriosis, defined as the growth of endometrial tissue outside the uterus, is a common gynecologic condition affecting millions of women worldwide. It is an inflammatory, estrogen-dependent complex disorder, with broad symptomatic variability, pelvic pain, and infertility being the main characteristics. Ovarian endometriomas are frequently developed in women with endometriosis. Late diagnosis is one of the main problems of endometriosis; thus, it is important to identify biomarkers for early diagnosis. The aim of the present work is to evaluate the ecto-nucleotidases activities in the contents of endometriomas. These enzymes, through the regulation of extracellular ATP and adenosine levels, are key enzymes in inflammatory processes, and their expression has been previously characterized in human endometrium. To achieve our objective, the echo-guided aspirated fluids of endometriomas were analyzed by evaluating the ecto-nucleotidases activities and compared with simple cysts. Our results show that enzyme activities are quantifiable in the ovarian cysts aspirates and that endometriomas show significantly higher ecto-nucleotidases activities than simple cysts (5.5-fold increase for ATPase and 20-fold for ADPase), thus being possible candidates for new endometriosis biomarkers. Moreover, we demonstrate the presence of ecto-nucleotidases bearing exosomes in these fluids. These results add up to the knowledge of the physiopathologic mechanisms underlying endometriosis and, open up a promising new field of study.

Spermatogenesis in house mouse in a Robertsonian polymorphism zone.

Robertsonian (Rb) translocations can be important in speciation as a mechanism of postzygotic isolation between populations. Meiotic non-disjunction, gametogenic impairment, and association of impaired autosomal segments with sex chromosomes have been postulated as mechanisms responsible for reducing fertility in Rb mice. Quantitative histological studies needed to understand the role of Rb fusions in gametogenic impairment are scarce. Most research on Rb mice has analyzed meiotic non-disjunction of laboratory and wild-derived strains, which have complex or simple structural heterozygosity with large numbers of fusions. Using histological multilevel sampling, we examined spermatogenesis in mice from the Rb polymorphism area of Barcelona. We studied four chromosomal groups having: a) one Rb heterozygote fusion and 2n=39, b) one Rb heterozygote fusion and 2n=31, c) three Rb heterozygote fusions without monobrachial homology and with diploid number ranging from 2n=29 to 2n=37, and d) only Rb homozygote fusions with diploid number ranging from 2n=28 to 2n=30. Standard mice from the area surrounding the Rb zone were used as control. We analyzed morphological variables of the testes, relative frequency of stages in the seminiferous epithelium cycle, the 'round spermatids:primary spermatocytes' ratio, and other derived parameters. Our results reveal that structural homozygote mice and simple heterozygote mice having as few as one to three Rb fusions undergo greater germ cell death (GCD) than standard mice, suggesting that Rb fusions are related to increased GCD (in both the heterozygous and homozygous state) and may be the main cause of decreased gene flow between mice populations from this area.

Differential lymphocyte infiltration in small airways and lung parenchyma in COPD patients.

BACKGROUND: In COPD, although histological lesions at both the small airways (wall thickening and tissue remodeling) and lung parenchyma (emphysematous destruction) are definitely different, the inflammatory cells involved in both processes are the same. Our study aims to determine if these histopathological phenotypes are related to two different lymphocyte profiles. METHODS: Distribution and cell density of CD3(+), CD4(+), CD8(+) and B lymphocytes were compared in small airways and parenchymal interstitium of 9 non-smokers, 18 smokers without COPD, 16 smokers with moderate COPD and 16 patients with very severe COPD undergoing lung transplantation. Spatial distribution of lymphocytes in periemphysematous parenchyma was also assessed. RESULTS: CD3(+) and B cell densities were significantly higher in small airways than parenchyma interstitium of very severe COPD patients. Furthermore, CD8(+) cells were increased in the epithelium of airways of moderate COPD patients compared to non-smokers. Although CD8(+) cell density was increased in parenchyma of COPD patients, CD8(+) and B cell densities were similar when comparing periemphysematous and non-emphysematous alveolar interstitium. CONCLUSIONS: In COPD, it is true that the small airways' wall shows a clear inflammatory pattern, with a high mononuclear infiltration and tissue remodeling. However, parenchymal interstitium shows a milder CD8(+) infiltration which, moreover, is not spatially related to emphysematous destroyed areas.

Evidence of innervation in talc-induced pleural adhesions.

STUDY OBJECTIVES: To conduct a detailed morphologic and ultrastructural study of pleural adhesions following talc pleurodesis. METHODS: Talc with a main particle size of 8.36 +/- 0.2 mum (mean +/- SEM) and at a dose of 200 mg/kg in a 2-mL slurry was instilled via a small catheter into the pleural cavity of 10 male rabbits. Five rabbits were killed at 1 week, and five rabbits were killed at 1 month after instillation. At autopsy, after macroscopically observing the pleural cavity, adhesions were excised from opposing pleural surfaces and processed for histopathologic, immunocytochemical, and ultrastructural study. RESULTS: At 1 week, all adhesions examined were mesothelium-covered fibrovascular bands containing well-developed blood and lymphatic vessels establishing a structural continuity between both pleural layers. Nerves were present in adhesions from 20% of the rabbits. They consisted of a single fascicle containing 5 to 20 thin myelinated axons of various diameters (1 to 6 microm) uniformly distributed throughout the nerve section. The anatomic location of the adhesion did not appear to influence its overall morphology. CONCLUSIONS: As early as at 1 week, adhesions are well-formed structures more resembling newly formed pleural tissue than a simple scar. Nerve fibers in pleural adhesions are reported for the first time, which suggests that these adhesions are potentially capable of conducting pain stimuli. Further studies are required in order to confirm our results in human pleural adhesions.

Ultrastructural localization of antigenic determinants conserved during Perkinsus atlanticus trophozoite to prezoosporangium differentiation.

Trophozoite, prezoosporangium and zoospore are the 3 main developmental stages that form the life cycle of protozoa of the genus Perkinsus. Several studies have shown that the differentiation of Perkinsus species from the trophozoite to the prezoosporangium stage involves a substantial modification of the antigenic characteristics of these molluscan parasites. With the aim of determining the presence and distribution of antigenic determinants conserved during trophozoite to prezoosporangium differentiation, a polyclonal serum was raised against trophozoites of P. atlanticus purified from parasitized gills of the clam Tapes semidecussatus. Immunocytochemical analyses showed that the serum generated against P. atlanticus trophozoites strongly cross-reacted with the prezoosporangium stage. Immunogold electron microscopy studies revealed that the granular component of the nucleolus, chromatin, cell wall, plasmalemma, lomasomes and vacuolar membrane are the main subcellular structures where the immunodominant epitopes consistently expressed by trophozoites and prezoosporangia are located. Furthermore, analysis of the immunogold staining pattern revealed that the labelling density obtained for prezoosporangia in the nucleolus, cell wall, plasmalemma and lomasomes was significantly higher than that obtained for trophozoites. The most immunoreactive structure in trophozoites was the granular component of the nucleolus, whereas in prezoosporangia it was the lomasome. Interestingly, the main antigenic compartment of P. atlanticus, considering both developmental stages, was the lomasome of the prezoosporangium. These findings show that P. atlanticus trophozoite to prezoosporangium differentiation is accompanied by significant qualitative and quantitative changes in the ultrastructural distribution of the immunodominant antigens shared by these 2 developmental stages.

Influence of talc dose on extrapleural talc dissemination after talc pleurodesis.

This study was designed to ascertain, in a rabbit model, extrapleural talc deposition and the related inflammatory response after talc slurry pleurodesis with two clinical doses, 200 and 50 mg/kg. Histopathologic evaluations revealed that whereas numerous rabbits receiving a high dose had talc in the ipsilateral (70%) and contralateral (55%) lung, mediastinum (90%), pericardium (30%), and liver (25%), a small number of animals treated with a low dose showed talc in the ipsilateral lung (10%) and mediastinum (20%) and none in the contralateral lung, pericardium, or liver. Hematologic and immunocytochemical analyses showed that a systemic inflammatory response develops shortly after pleurodesis with a high talc dose involving massive accumulation of neutrophils and macrophages in lung tissue. Zymography also revealed that the pulmonary expression of matrix metalloproteinases 2 and 9 was up-regulated in both lungs in a dose-dependent manner soon after talc instillation. Furthermore, microscopic examination of lung specimens revealed that the higher the dose of talc, the greater the development of both fibrotic visceral pleural thickening and foreign-body granulomas. These findings show pleurodesis with a high talc dose to be associated with an increased risk of extrapleural talc deposition, which may originate undesirable acute and chronic inflammatory responses.

Influence of particle size on extrapleural talc dissemination after talc slurry pleurodesis.

BACKGROUND: Cases of acute respiratory failure reported after talc pleurodesis have raised concerns about its safety. It has been speculated that this pulmonary inflammatory syndrome is secondary to the extrapleural dissemination of the talc particles. STUDY OBJECTIVES: To test the hypothesis that particle size influences extrapleural talc deposition and pleural inflammation after talc slurry pleurodesis. DESIGN: Thirty rabbits underwent pleurodesis as follows: 10 rabbits received 200 mg/kg of the talc used for human pleurodesis, normal talc (NT); 10 rabbits received 200 mg/kg of talc with particles of larger size, large talc (LT); and 10 rabbits received saline solution. Samples from the ipsilateral lung, chest wall, diaphragm, mediastinal pleura, heart, liver, spleen, and right kidney were obtained at 24 h and 7 days and processed for optic and electron microscopy and energy-dispersive x-ray analysis. RESULTS: Visceral pleural thickening was greater with NT than with LT, but no differences were observed in the macroscopic score of adhesions. There was more talc in the lungs of the rabbits that received NT than in those that received LT. Talc particles were detected in mediastinum (100%) and pericardium (20%), irrespective of the talc used. Three animals, all receiving NT, had talc particles in the liver. CONCLUSIONS: Our study shows that while both talcs were equally effective in achieving pleurodesis, the intrapleural injection of NT elicits greater pulmonary and systemic talc particle deposition than LT. Moreover, pleural inflammation was greater with NT than with LT.

Vascular involvement and cell damage in experimental AA and clinical beta(2)-microglobulin amyloidosis.

BACKGROUND: Amyloidosis is a highly prevalent disease characterized by the deposition of amyloid fibrils. Although several types of amyloidosis can be identified according to their protein constituents and suggest putative aetiological factors, the causes of amyloidosis remain unknown. Furthermore, the cellular participation and the ultrastructural particularities of amyloidosis have received little attention. The aim of our study was to evaluate the vascular participation in amyloidosis and the cellular consequences of this disease. METHODS: Two forms of amyloidosis were studied: experimental amyloid A (AA) and clinical beta(2)-microglobulin amyloidosis. We studied kidney, liver, and spleen in a mouse model, and examined surgically obtained carpal deposits from dialysis patients. We used light and electron microscopy with immunogold labelling for anti-beta(2)-microglobulin and anti-AA protein antibodies. RESULTS: AA amyloid fibril accumulation was associated with membrane lesions in basal, cytoplasmic organelle (endoplasmic reticulum, mitochondria), and nuclear membranes. Amyloid fibrils from beta(2)-microglobulin amyloidosis were also closely associated with elastic fibres and endothelial basement membrane. We observed proliferation of endothelial cells as well as basement membrane enlargement and disruption. CONCLUSIONS: Vascular abnormalities, including endothelial enlargement, basement membrane modifications, and vascular proliferation were associated with amyloidosis. Amyloid fibrils have a high avidity for elastic fibres and are able to contact and damage the basement membrane, the cell and intracellular organelle membranes, as well as the nuclear envelope, suggesting a toxic effect of amyloid fibrils on cells.