AIMS: Cigarette smoke often induces pulmonary and systemic inflammation. In animal models, mesenchymal stem cells (MSC) tend to ameliorate these effects. We aimed to explore the local and systemic expression of cytokines in guinea pigs chronically exposed to cigarette smoke, and their modifications by MSC. MAIN METHODS: Concentrations of IL-1ß, IL-6, IL-8, IL-12, TNF-α, INF-É£, TSG-6, MMP-9, TIMP-1, and/or TIMP-2 in serum and bronchoalveolar lavage (BALF) from animals exposed to tobacco smoke (20 cigarettes/day, 5 days/week for 10 weeks) were determined, and mRNA expression of some of them was measured in lung tissue. Intratracheal instillation of allogeneic bone marrow MSC (5x106 cells in 1 ml) was done at week 2. KEY FINDINGS: After cigarette smoke, IL-6 and IFN-γ increased in serum and BALF, while IL-1ß and IL-12 decreased in serum, and TSG-6 and TIMP-2 increased in BALF. IL-1ß had a paradoxical increase in BALF. MSC had an almost null effect in unexposed animals. The intratracheal administration of MSC in guinea pigs exposed to cigarette smoke was associated with a statistically significant decrease of IL-12 and TSG-6 in serum, as well as a decrease of IL-1ß and IFN-γ and an increase in TIMP-1 in BALF. Concerning mRNA expression in lung tissue, cigarette smoke did not modify the relative amount of the studied transcripts, but even so, MSC decreased the IL-12 mRNA and increased the TIMP-1 mRNA. SIGNIFICANCE: A single intratracheal instillation of MSC reduces the pulmonary and systemic proinflammatory pattern induced by chronic exposure to cigarette smoke in guinea pigs. TRIAL REGISTRATION: Not applicable.
Cigarette Smoking , Mesenchymal Stem Cells , Guinea Pigs , Animals , Cytokines/metabolism , Tissue Inhibitor of Metalloproteinase-1/metabolism , Tissue Inhibitor of Metalloproteinase-2 , Interleukin-6/pharmacology , Cigarette Smoking/adverse effects , Lung/metabolism , Interleukin-12/pharmacology , RNA, Messenger , Mesenchymal Stem Cells/metabolism , Bronchoalveolar Lavage Fluid
AIM OF THE STUDY: Long-term exposure to cigarette smoke generates chronic obstructive pulmonary disease (COPD) in guinea pigs, but a comprehensive evaluation of changes in lung function, as assessed by barometric whole body plethysmography (WBP), is lacking. MATERIALS AND METHODS: Female guinea pigs were exposed to the smoke of 20 cigarettes/day, 5 days/week, during 10 weeks (COPD group, n = 8), and were compared with unexposed female guinea pigs of the same age (control group, n = 8). WBP was performed in both groups, followed by lung histology. RESULTS: At the end of the exposure period, guinea pigs in the COPD group had higher respiratory frequency, while duty cycle (Ti/Ttot) was unaffected. There was a trend toward minute ventilation (MV) and expiratory flow at the mid-tidal volume (EF50) to be higher in the COPD group. Enhanced pause (Penh) was lower, while time of braking (TB) and time to PEF relative to Te (Rpef) were higher in the COPD group. All guinea pigs exposed to tobacco smoke developed emphysematous lesions in their lungs and gained less body weight than controls. CONCLUSIONS: In this COPD model, exposure to cigarette smoke produced changes in WBP characterized by a shallow breathing pattern with decreased Penh and a trend toward increasing EF50 (probably due to decreased elastic recoil), increased TB (suggesting dynamic laryngeal narrowing), and a trend of increasing MV (probably due to a higher metabolic rate). Many of these functional changes resemble those observed in patients with COPD and corroborate the suitability of this guinea pig model for the study of COPD.
Plethysmography/methods , Pulmonary Disease, Chronic Obstructive/etiology , Smoke/adverse effects , Animals , Disease Models, Animal , Female , Guinea Pigs , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Ventilation , Respiration , Respiratory Function Tests , Tidal Volume , Tobacco Products
Currently, there are no surgical strategies to treat tracheal lesions longer than 7 cm. Such patients are not candidates for tracheal resection or end-to-end anastomosis and are thus left with only repeated palliative procedures to relieve their respiratory insufficiency. Experimental studies using cryopreserved trachea have produced contradictory results, limiting the clinical application of this technique. We evaluated caspase-3 expression and the histological integrity of canine tracheal cartilage cryopreserved using two different solutions, two temperatures, and varying lengths of storage time. Thirty canine tracheal segments of 5 rings were studied. Group 1: Control without cryopreservation. Groups 2 and 4: Cryopreserved in F12K media with 20% fetal bovine serum (FBS) at -70°C for 48 hours. Groups 3 and 5: Cryopreserved in 90% FBS at -70°C for 48 hours. Groups 4 and 5 were then stored for 15 days in liquid nitrogen. All of the segments were thawed, fixed in wax, and cut into rings. Three rings were selected for caspase-3 expression and histological evaluation. Staining of cartilage matrices was significantly modified in the tracheal segments of Group 5. The central region of the cartilage ring was more vulnerable to the effects of freezing than the edges. Under the same cryopreservation temperature and storage time, tracheal cartilage integrity is better preserved when F12K media is used. Caspase-3 expression is not related to cartilage injury from the cryopreservation process.
Cartilage/metabolism , Caspase 3/metabolism , Cryopreservation , Trachea/metabolism , Animals , Cartilage/pathology , Cryoprotective Agents/chemistry , Dogs , Freezing , Temperature , Time Factors , Trachea/pathology
Los miofibroblastos representan una subpoblación de fibroblastos con un fenotipo similar al de las células del músculo liso, debido a que expresan a-actina de músculo liso en su citoesqueleto, aunque también como subpoblación exhiben diferencias fenotípicas entre sí en diferentes órganos, su fisiología es semejante en los diferentes tejidos y órganos en que se encuentren. Con base en su amplio espectro de síntesis y secreción de moléculas, tales como citocinas, interleucinas, quimiocinas, factores del crecimiento, lípidos, diversos mediadores fisiológicos, moléculas de la matriz extracelular, MMPs y TIMPs, desempeñan una participación muy importante durante la embriogénesis, organogénesis, inflamación, reparación y cicatrización, siendo además fundamentales en los diferentes procesos de regeneración y reparación (fibrosis) que ocurren en los distintos órganos. En el caso del sistema respiratorio, los miofibroblastos son importantes, tanto en las vías aéreas como en el pulmón, participando fundamentalmente en los diversos procesos patogénicos, ya sea en enfermedades con un patrón degradativo como el enfisema, o bien, con un patrón reparativo con depósito excesivo de los diversos componentes de la matriz extracelular, tal como ocurre en la fibrosis pulmonar y el asma. Son especialmente importantes en las diferentes formas de fibrosis pulmonar ya sea de causa conocida o idiopática. Esta última, a semejanza del asma, parece restringirse fundamentalmente a zonas del tejido adyacente a epitelios alveolares dañado, donde se da una relación fisiopatogénica neumocito tipo II-miofibroblasto-fibroblasto. Los miofibroblastos se originan principalmente por transdiferenciación de fibroblastos y principalmente por estimulación del TGF-β1.
Myofibroblasts are a fibroblast subpopulation with a phenotype similar to smooth muscle cells, since they express the cytoskeletal a-smooth muscle actin (α-SMA); however, in different organs, they show some phenotypical differences. Their physiology is similar in the different tissues and organs. Based on their extensive spectrum of synthesis and secretion of molecules such as cytokines, interleukins, chemokines, growth factors, lipids, diverse physiological mediators, molecules of the extracelullar matrix, MMPs and TIMPs, they play a very important role during embryogenesis, organogenesis, inflammation, repair and wound healing, besides being fundamental in the processes of regeneration and repair (fibrosis) that occur in the different organs. In the case of the respiratory system, the myofibroblasts are as important in the air ways as in the lung, mainly participating in the diverse pathogenic processes; whether in pathologies with a derivative pattern such as emphysema, or in diseases with a fibrogenic pattern with excessive synthesis of the diverse components of the extracellular matrix, as occurs in pulmonary fibrosis and asthma. Myofibroblasts are especially important in the different forms of pulmonary fibrosis whether idiopathic or of known cause. Idiopathic fibrosis, as asthma, seems to be essentially restricted to areas of tissue adjacent to damaged alveolar-epithelial areas, where a physiopathogenic relation of type II neumocyte-myofibroblast-fibroblast exists. On the other hand, myofibroblasts are mostly derived from fibroblast transdifferentiation by TGF-β1 stimulation.
La enfermedad pulmonar obstructiva crónica es un término cuyo espectro incluye a la bronquitis crónica, a la enfermedad de la vía aérea pequeña y al enfisema pulmonar. En este trabajo despúes de definir cada una de estas entidades, se abordó la etiopatogénesis de la enfermedad pulmonar obstructiva crónica como una entidad funcional única, sin considerar si la enfermedad de la vía aérea pequeña o el enfisema, contribuyen de manera independiente en mayor o menor grado a tal obstrucción. Aunque prácticamente, los mismo factores de riesgo están implicados en la patogénesis de las tres entidades, en este trabajo se discuten los probables mecanismos por los que esos diferentes factores pueden conducir a la limitación del flujo en la vía aérea. Finalmente, en relación al enfisema pulmonar, se revisa desde su origen, la teoría del desequilibrio proteasas-antiproteasas, como la hipótesis que en la actualidad es más aceptada para explicar la génesis de la destrucción pulmonar
alpha 1-Antitrypsin , Environmental Pollution/adverse effects , Macrophages, Alveolar/enzymology , Lung Diseases, Obstructive/enzymology , Lung Diseases, Obstructive/etiology , Lung Diseases, Obstructive/physiopathology , Ozone/adverse effects , Pancreatic Elastase , Peptide Hydrolases , Pulmonary Emphysema/enzymology , Pulmonary Emphysema/etiology
La matriz extracelular (ME) del tejido conectivo pulmonar se diferencia en membranas basales y matriz intersticial. Esta última se constituye por un armazón de proteínas colagénicas fibrosas y de fibras elásticas amorfas, que están embebidas dentro de una sustancia basal viscoelástica compuesta por proteoglicanos y glicoproteínas. La ME le proporciona al pulmón sus propiedad mecánicas. Las colágenas proveen tensión, mientras que las fibras elásticas permiten el desarrollo de la expansión elástica, con la subsecuente recuperación característica de este órgano. Las fibras elásticas se constituyen por fibras amorfas de elastina polimérica combinada con ciertas glicoproteínas conocidas como microfibrillas, con proporciones variables según su estadio ontogénico. Este material amorfo constituye toda una malla que comprende un armazón continuo, por todo el pulmón, y en conexión estrecha con las fibras de colágena permite la actividad mecánica del pulmón. La elastina es una molécula altamente hidrofóbica, con una relación intron: exón de 15:1, sintetizada junto con un receptor que guía su polimerización en sitios determinados por las microfibrillas previamente depositadas
Dogs , Humans , Animals , alpha 1-Antitrypsin/deficiency , Elastin/chemistry , Elastin/metabolism , Molecular Structure , Pulmonary Emphysema/physiopathology , Elastic Tissue/chemistry , Elastic Tissue/ultrastructure , Tropoelastin/chemical synthesis
